4b22b9337f359bfd063322244f5336cc7c6ffcfars/* -*- Mode: C; tab-width: 4 -*-
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome * Copyright (c) 2002-2015 Apple Inc. All rights reserved.
4b22b9337f359bfd063322244f5336cc7c6ffcfars * Licensed under the Apache License, Version 2.0 (the "License");
4b22b9337f359bfd063322244f5336cc7c6ffcfars * you may not use this file except in compliance with the License.
4b22b9337f359bfd063322244f5336cc7c6ffcfars * You may obtain a copy of the License at
4b22b9337f359bfd063322244f5336cc7c6ffcfars * Unless required by applicable law or agreed to in writing, software
4b22b9337f359bfd063322244f5336cc7c6ffcfars * distributed under the License is distributed on an "AS IS" BASIS,
4b22b9337f359bfd063322244f5336cc7c6ffcfars * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
4b22b9337f359bfd063322244f5336cc7c6ffcfars * See the License for the specific language governing permissions and
4b22b9337f359bfd063322244f5336cc7c6ffcfars * limitations under the License.
4b22b9337f359bfd063322244f5336cc7c6ffcfars * This code is completely 100% portable C. It does not depend on any external header files
4b22b9337f359bfd063322244f5336cc7c6ffcfars * from outside the mDNS project -- all the types it expects to find are defined right here.
4b22b9337f359bfd063322244f5336cc7c6ffcfars * The previous point is very important: This file does not depend on any external
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome * header files. It should compile on *any* platform that has a C compiler, without
4b22b9337f359bfd063322244f5336cc7c6ffcfars * making *any* assumptions about availability of so-called "standard" C functions,
4b22b9337f359bfd063322244f5336cc7c6ffcfars * routines, or types (which may or may not be present on any given platform).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#include "DNSCommon.h" // Defines general DNS utility routines
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#include "uDNS.h" // Defines entry points into unicast-specific routines
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Disable certain benign warnings with Microsoft compilers
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#if (defined(_MSC_VER))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Disable "conditional expression is constant" warning for debug macros.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Otherwise, this generates warnings for the perfectly natural construct "while(1)"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// If someone knows a variant way of writing "while(1)" that doesn't generate warning messages, please let us know
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Disable "assignment within conditional expression".
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Other compilers understand the convention that if you place the assignment expression within an extra pair
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// of parentheses, this signals to the compiler that you really intended an assignment and no warning is necessary.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// The Microsoft compiler doesn't understand this convention, so in the absense of any other way to signal
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// to the compiler that the assignment is intentional, we have to just turn this warning off completely.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#include "dns_sd.h" // for kDNSServiceFlags* definitions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomeWCFConnection *WCFConnectionNew(void) __attribute__((weak_import));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soomevoid WCFConnectionDealloc(WCFConnection* c) __attribute__((weak_import));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Do we really need to define a macro for "if"?
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // ! NO_WCF
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // APPLE_OSX_mDNSResponder
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Forward declarations
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void BeginSleepProcessing(mDNS *const m);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void RetrySPSRegistrations(mDNS *const m);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void SendWakeup(mDNS *const m, mDNSInterfaceID InterfaceID, mDNSEthAddr *EthAddr, mDNSOpaque48 *password);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool CacheRecordRmvEventsForQuestion(mDNS *const m, DNSQuestion *q);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool LocalRecordRmvEventsForQuestion(mDNS *const m, DNSQuestion *q);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNS_PurgeForQuestion(mDNS *const m, DNSQuestion *q);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void CheckForDNSSECRecords(mDNS *const m, DNSQuestion *q);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNS_SendKeepalives(mDNS *const m);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNS_ExtractKeepaliveInfo(AuthRecord *ar, mDNSu32 *timeout, mDNSAddr *laddr, mDNSAddr *raddr, mDNSEthAddr *eth,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu32 *seq, mDNSu32 *ack, mDNSIPPort *lport, mDNSIPPort *rport, mDNSu16 *win);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void AdvertiseAllInterfaceRecords(mDNS *const m);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void DeadvertiseAllInterfaceRecords(mDNS *const m);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void FreeNSECRecords(mDNS *const m, CacheRecord *NSECRecords);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNSParseNSEC3Records(mDNS *const m, const DNSMessage *const response, const mDNSu8 *end,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSInterfaceID InterfaceID, CacheRecord **NSEC3Records);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas SoomemDNSlocal mDNSu8 *GetValueForMACAddr(mDNSu8 *ptr, mDNSu8 *limit, mDNSEthAddr *eth);
4b22b9337f359bfd063322244f5336cc7c6ffcfars// ***************************************************************************
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// To Turn OFF mDNS_Tracer set MDNS_TRACER to 0 or undef it
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Any records bigger than this are considered 'large' records
4b22b9337f359bfd063322244f5336cc7c6ffcfars#define kUpdateCreditRefreshInterval (mDNSPlatformOneSecond * 6)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// define special NR_AnswerTo values
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Defined to set the kDNSQClass_UnicastResponse bit in the first four query packets.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// else, it's just set it the first query.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// The code (see SendQueries() and BuildQuestion()) needs to have the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// RequestUnicast value set to a value one greater than the number of times you want the query
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// sent with the "request unicast response" (QU) bit set.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// ***************************************************************************
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Returns true if this is a unique, authoritative LocalOnly record that answers questions of type
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// A, AAAA , CNAME, or PTR. The caller should answer the question with this record and not send out
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// the question on the wire if LocalOnlyRecordAnswersQuestion() also returns true.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Main use is to handle /etc/hosts records and the LocalOnly PTR records created for localhost.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#define UniqueLocalOnlyRecord(rr) ((rr)->ARType == AuthRecordLocalOnly && \
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (rr)->resrec.RecordType & kDNSRecordTypeUniqueMask && \
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ((rr)->resrec.rrtype == kDNSType_A || (rr)->resrec.rrtype == kDNSType_AAAA || \
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void SetNextQueryStopTime(mDNS *const m, const DNSQuestion *const q)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->NextScheduledStopTime - q->StopTime > 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void SetNextQueryTime(mDNS *const m, const DNSQuestion *const q)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Depending on whether this is a multicast or unicast question we want to set either:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // m->NextScheduledQuery = NextQSendTime(q) or
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // m->NextuDNSEvent = NextQSendTime(q)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSs32 *const timer = mDNSOpaque16IsZero(q->TargetQID) ? &m->NextScheduledQuery : &m->NextuDNSEvent;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void ReleaseAuthEntity(AuthHash *r, AuthEntity *e)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#if APPLE_OSX_mDNSResponder && MACOSX_MDNS_MALLOC_DEBUGGING >= 1
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome unsigned int i;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<sizeof(*e); i++) ((char*)e)[i] = 0xFF;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void ReleaseAuthGroup(AuthHash *r, AuthGroup **cp)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("ReleaseAuthGroup: Releasing AuthGroup %##s", (*cp)->name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("ERROR: (*cp)->members == mDNSNULL but (*cp)->rrauth_tail != &(*cp)->members)");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((*cp)->name != (domainname*)((*cp)->namestorage)) mDNSPlatformMemFree((*cp)->name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal AuthEntity *GetAuthEntity(AuthHash *r, const AuthGroup *const PreserveAG)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (r->rrauth_lock) { LogMsg("GetFreeCacheRR ERROR! Cache already locked!"); return(mDNSNULL); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We allocate just one AuthEntity at a time because we need to be able
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // free them all individually which normally happens when we parse /etc/hosts into
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // AuthHash where we add the "new" entries and discard (free) the already added
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // entries. If we allocate as chunks, we can't free them individually.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AuthEntity *storage = mDNSPlatformMemAllocate(sizeof(AuthEntity));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we still have no free records, recycle all the records we can.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Enumerating the entire auth is moderately expensive, so when we do it, we reclaim all the records we can in one pass.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((*cp)->members || (*cp)==PreserveAG) cp=&(*cp)->next;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("GetAuthEntity: Recycled %d records to reduce auth cache from %d to %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome oldtotalused - r->rrauth_totalused, oldtotalused, r->rrauth_totalused);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (r->rrauth_free) // If there are records in the free list, take one
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("RR Auth now using %ld objects", r->rrauth_totalused);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (r->rrauth_report < 100) r->rrauth_report += 10;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (r->rrauth_report < 1000) r->rrauth_report += 100;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport AuthGroup *AuthGroupForName(AuthHash *r, const mDNSu32 slot, const mDNSu32 namehash, const domainname *const name)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (ag = r->rrauth_hash[slot]; ag; ag=ag->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ag->namehash == namehash && SameDomainName(ag->name, name))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport AuthGroup *AuthGroupForRecord(AuthHash *r, const mDNSu32 slot, const ResourceRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome return(AuthGroupForName(r, slot, rr->namehash, rr->name));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal AuthGroup *GetAuthGroup(AuthHash *r, const mDNSu32 slot, const ResourceRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AuthGroup *ag = (AuthGroup*)GetAuthEntity(r, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!ag) { LogMsg("GetAuthGroup: Failed to allocate memory for %##s", rr->name->c); return(mDNSNULL); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("GetAuthGroup: Failed to allocate name storage for %##s", rr->name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (AuthGroupForRecord(r, slot, rr)) LogMsg("GetAuthGroup: Already have AuthGroup for %##s", rr->name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (AuthGroupForRecord(r, slot, rr) != ag) LogMsg("GetAuthGroup: Not finding AuthGroup for %##s", rr->name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Returns the AuthGroup in which the AuthRecord was inserted
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport AuthGroup *InsertAuthRecord(mDNS *const m, AuthHash *r, AuthRecord *rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu32 slot = AuthHashSlot(rr->resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!ag) ag = GetAuthGroup(r, slot, &rr->resrec); // If we don't have a AuthGroup for this name, make one now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("InsertAuthRecord: inserting auth record %s from table", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *(ag->rrauth_tail) = rr; // Append this record to tail of cache slot list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ag->rrauth_tail = &(rr->next); // Advance tail pointer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport AuthGroup *RemoveAuthRecord(mDNS *const m, AuthHash *r, AuthRecord *rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu32 slot = AuthHashSlot(rr->resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!a) { LogMsg("RemoveAuthRecord: ERROR!! AuthGroup not found for %s", ARDisplayString(m, rr)); return mDNSNULL; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We don't break here, so that we can set the tail below without tracking "prev" pointers
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("RemoveAuthRecord: removing auth record %s from table", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // TBD: If there are no more members, release authgroup ?
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport CacheGroup *CacheGroupForName(const mDNS *const m, const mDNSu32 slot, const mDNSu32 namehash, const domainname *const name)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (cg = m->rrcache_hash[slot]; cg; cg=cg->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (cg->namehash == namehash && SameDomainName(cg->name, name))
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal CacheGroup *CacheGroupForRecord(const mDNS *const m, const mDNSu32 slot, const ResourceRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome return(CacheGroupForName(m, slot, rr->namehash, rr->name));
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas SoomemDNSexport mDNSBool mDNS_AddressIsLocalSubnet(mDNS *const m, const mDNSInterfaceID InterfaceID, const mDNSAddr *addr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Normally we resist touching the NotAnInteger fields, but here we're doing tricky bitwise masking so we make an exception
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSv4AddressIsLinkLocal(&addr->ip.v4)) return(mDNStrue);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = m->HostInterfaces; intf; intf = intf->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (intf->ip.type == addr->type && intf->InterfaceID == InterfaceID && intf->McastTxRx)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (((intf->ip.ip.v4.NotAnInteger ^ addr->ip.v4.NotAnInteger) & intf->mask.ip.v4.NotAnInteger) == 0)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (mDNSv6AddressIsLinkLocal(&addr->ip.v6)) return(mDNStrue);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = m->HostInterfaces; intf; intf = intf->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (intf->ip.type == addr->type && intf->InterfaceID == InterfaceID && intf->McastTxRx)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((((intf->ip.ip.v6.l[0] ^ addr->ip.v6.l[0]) & intf->mask.ip.v6.l[0]) == 0) &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (((intf->ip.ip.v6.l[1] ^ addr->ip.v6.l[1]) & intf->mask.ip.v6.l[1]) == 0) &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (((intf->ip.ip.v6.l[2] ^ addr->ip.v6.l[2]) & intf->mask.ip.v6.l[2]) == 0) &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (((intf->ip.ip.v6.l[3] ^ addr->ip.v6.l[3]) & intf->mask.ip.v6.l[3]) == 0))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal NetworkInterfaceInfo *FirstInterfaceForID(mDNS *const m, const mDNSInterfaceID InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome NetworkInterfaceInfo *intf = m->HostInterfaces;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (intf && intf->InterfaceID != InterfaceID) intf = intf->next;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal NetworkInterfaceInfo *FirstIPv4LLInterfaceForID(mDNS *const m, const mDNSInterfaceID InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: We don't check for InterfaceActive, as the active interface could be IPv6 and
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we still want to find the first IPv4 Link-Local interface
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = m->HostInterfaces; intf; intf = intf->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome intf->ip.type == mDNSAddrType_IPv4 && mDNSv4AddressIsLinkLocal(&intf->ip.ip.v4))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("FirstIPv4LLInterfaceForID: found LL interface with address %.4a", &intf->ip.ip.v4);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport char *InterfaceNameForID(mDNS *const m, const mDNSInterfaceID InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome NetworkInterfaceInfo *intf = FirstInterfaceForID(m, InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Caller should hold the lock
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void GenerateNegativeResponse(mDNS *const m, QC_result qc)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!m->CurrentQuestion) { LogMsg("GenerateNegativeResponse: ERROR!! CurrentQuestion not set"); return; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("GenerateNegativeResponse: Generating negative response for question %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome MakeNegativeCacheRecord(m, &m->rec.r, &q->qname, q->qnamehash, q->qtype, q->qclass, 60, mDNSInterface_Any, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We need to force the response through in the following cases
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // a) SuppressUnusable questions that are suppressed
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // b) Append search domains and retry the question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // The question may not have set Intermediates in which case we don't deliver negative responses. So, to force
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // through we use "QC_forceresponse".
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnswerCurrentQuestionWithResourceRecord(m, &m->rec.r, qc);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentQuestion == q) { q->ThisQInterval = 0; } // Deactivate this question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Don't touch the question after this
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void AnswerQuestionByFollowingCNAME(mDNS *const m, DNSQuestion *q, ResourceRecord *rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSBool selfref = SameDomainName(&q->qname, &rr->rdata->u.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("AnswerQuestionByFollowingCNAME: %p %##s (%s) NOT following CNAME referral %d%s for %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q, q->qname.c, DNSTypeName(q->qtype), q->CNAMEReferrals, selfref ? " (Self-Referential)" : "", RRDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu32 c = q->CNAMEReferrals + 1; // Stash a copy of the new q->CNAMEReferrals value
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // if there is a message waiting at the socket, we want to process that instead
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // of throwing it away. If we have a CNAME response that answers
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // both A and AAAA question and while answering it we don't want to throw
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // away the response where the actual addresses are present.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // This is a stupid hack and we should get rid of it.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // The chance of there being a second unicast UDP packet already waiting in the kernel before we’ve
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // finished processing the previous one is virtually nil, and will only happen by luck on very rare
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // occasions when running on a machine with a fast network connection and a slow or busy processor.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // The idea that we’d rely for correctness on this random chance event occurring is ridiculous.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("AnswerQuestionByFollowingCNAME: Preserving UDP socket for %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // The SameDomainName check above is to ignore bogus CNAME records that point right back at
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // themselves. Without that check we can get into a case where we have two duplicate questions,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // A and B, and when we stop question A, UpdateQuestionDuplicates copies the value of CNAMEReferrals
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // from A to B, and then A is re-appended to the end of the list as a duplicate of B (because
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the target name is still the same), and then when we stop question B, UpdateQuestionDuplicates
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // copies the B's value of CNAMEReferrals back to A, and we end up not incrementing CNAMEReferrals
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // for either of them. This is not a problem for CNAME loops of two or more records because in
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // those cases the newly re-appended question A has a different target name and therefore cannot be
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // a duplicate of any other question ('B') which was itself a duplicate of the previous question A.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Right now we just stop and re-use the existing query. If we really wanted to be 100% perfect,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and track CNAMEs coming and going, we should really create a subordinate query here,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // which we would subsequently cancel and retract if the CNAME referral record were removed.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // In reality this is such a corner case we'll ignore it until someone actually needs it.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("AnswerQuestionByFollowingCNAME: %p %##s (%s) following CNAME referral %d for %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q, q->qname.c, DNSTypeName(q->qtype), q->CNAMEReferrals, RRDisplayString(m, rr));
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if ((qNameLen > 0) && (qNameLen <= MAX_DOMAIN_NAME))
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome originalQName = mDNSPlatformMemAllocate(qNameLen);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome mDNSPlatformMemCopy(originalQName->c, q->qname.c, qNameLen);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_StopQuery_internal(m, q); // Stop old query
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName(&q->qname, &rr->rdata->u.name); // Update qname
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->qnamehash = DomainNameHashValue(&q->qname); // and namehash
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If a unicast query results in a CNAME that points to a .local, we need to re-try
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // this as unicast. Setting the mDNSInterface_Unicast tells mDNS_StartQuery_internal
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to try this as unicast query even though it is a .local name
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!mDNSOpaque16IsZero(q->TargetQID) && IsLocalDomain(&q->qname))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("AnswerQuestionByFollowingCNAME: Resolving a .local CNAME %p %##s (%s) Record %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q, q->qname.c, DNSTypeName(q->qtype), RRDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_StartQuery_internal(m, q); // start new query
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Record how many times we've done this. We need to do this *after* mDNS_StartQuery_internal,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // because mDNS_StartQuery_internal re-initializes CNAMEReferrals to zero
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We have a message waiting and that should answer this question.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// For a single given DNSQuestion pointed to by CurrentQuestion, deliver an add/remove result for the single given AuthRecord
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Note: All the callers should use the m->CurrentQuestion to see if the question is still valid or not
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void AnswerLocalQuestionWithLocalAuthRecord(mDNS *const m, AuthRecord *rr, QC_result AddRecord)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("AnswerLocalQuestionWithLocalAuthRecord: ERROR!! CurrentQuestion NULL while answering with %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome followcname = FollowCNAME(q, &rr->resrec, AddRecord);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We should not be delivering results for record types Unregistered, Deregistering, and (unverified) Unique
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!(rr->resrec.RecordType & kDNSRecordTypeActiveMask))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("AnswerLocalQuestionWithLocalAuthRecord: *NOT* delivering %s event for local record type %X %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AddRecord ? "Add" : "Rmv", rr->resrec.RecordType, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Indicate that we've given at least one positive answer for this record, so we should be prepared to send a goodbye for it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Don't send this packet on the wire as we answered from /etc/hosts
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->QuestionCallback(m, q, &rr->resrec, AddRecord);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // The callback above could have caused the question to stop. Detect that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // using m->CurrentQuestion
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnswerQuestionByFollowingCNAME(m, q, &rr->resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->QuestionCallback(m, q, &rr->resrec, AddRecord);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void AnswerInterfaceAnyQuestionsWithLocalAuthRecord(mDNS *const m, AuthRecord *rr, QC_result AddRecord)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("AnswerInterfaceAnyQuestionsWithLocalAuthRecord: ERROR m->CurrentQuestion already set: %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (m->CurrentQuestion && m->CurrentQuestion != m->NewQuestions)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome answered = ResourceRecordAnswersQuestion(&rr->resrec, q);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome answered = LocalOnlyRecordAnswersQuestion(rr, q);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnswerLocalQuestionWithLocalAuthRecord(m, rr, AddRecord); // MUST NOT dereference q again
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentQuestion == q) // If m->CurrentQuestion was not auto-advanced, do it ourselves now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// When a new local AuthRecord is created or deleted, AnswerAllLocalQuestionsWithLocalAuthRecord()
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// delivers the appropriate add/remove events to listening questions:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// 1. It runs though all our LocalOnlyQuestions delivering answers as appropriate,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// stopping if it reaches a NewLocalOnlyQuestion -- brand-new questions are handled by AnswerNewLocalOnlyQuestion().
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// 2. If the AuthRecord is marked mDNSInterface_LocalOnly or mDNSInterface_P2P, then it also runs though
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// our main question list, delivering answers to mDNSInterface_Any questions as appropriate,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// stopping if it reaches a NewQuestion -- brand-new questions are handled by AnswerNewQuestion().
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// AnswerAllLocalQuestionsWithLocalAuthRecord is used by the m->NewLocalRecords loop in mDNS_Execute(),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// and by mDNS_Deregister_internal()
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void AnswerAllLocalQuestionsWithLocalAuthRecord(mDNS *const m, AuthRecord *rr, QC_result AddRecord)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("AnswerAllLocalQuestionsWithLocalAuthRecord ERROR m->CurrentQuestion already set: %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (m->CurrentQuestion && m->CurrentQuestion != m->NewLocalOnlyQuestions)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We are called with both LocalOnly/P2P record or a regular AuthRecord
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome answered = ResourceRecordAnswersQuestion(&rr->resrec, q);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome answered = LocalOnlyRecordAnswersQuestion(rr, q);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnswerLocalQuestionWithLocalAuthRecord(m, rr, AddRecord); // MUST NOT dereference q again
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentQuestion == q) // If m->CurrentQuestion was not auto-advanced, do it ourselves now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this AuthRecord is marked LocalOnly or P2P, then we want to deliver it to all local 'mDNSInterface_Any' questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->ARType == AuthRecordLocalOnly || rr->ARType == AuthRecordP2P)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnswerInterfaceAnyQuestionsWithLocalAuthRecord(m, rr, AddRecord);
4b22b9337f359bfd063322244f5336cc7c6ffcfars// ***************************************************************************
4b22b9337f359bfd063322244f5336cc7c6ffcfars#define RRTypeIsAddressType(T) ((T) == kDNSType_A || (T) == kDNSType_AAAA)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#define ResourceRecordIsValidAnswer(RR) ( ((RR)->resrec.RecordType & kDNSRecordTypeActiveMask) && \
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ((RR)->Additional1 == mDNSNULL || ((RR)->Additional1->resrec.RecordType & kDNSRecordTypeActiveMask)) && \
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ((RR)->Additional2 == mDNSNULL || ((RR)->Additional2->resrec.RecordType & kDNSRecordTypeActiveMask)) && \
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ((RR)->DependentOn == mDNSNULL || ((RR)->DependentOn->resrec.RecordType & kDNSRecordTypeActiveMask)) )
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ((RR)->resrec.InterfaceID == mDNSInterface_Any || (RR)->resrec.InterfaceID == (INTID)))
4b22b9337f359bfd063322244f5336cc7c6ffcfars#define DefaultProbeCountForRecordType(X) ((X) == kDNSRecordTypeUnique ? DefaultProbeCountForTypeUnique : (mDNSu8)0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// See RFC 6762: "8.3 Announcing"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// "The Multicast DNS responder MUST send at least two unsolicited responses, one second apart."
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Send 4, which is really 8 since we send on both IPv4 and IPv6.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// For goodbye packets we set the count to 3, and for wakeups we set it to 18
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// (which will be up to 15 wakeup attempts over the course of 30 seconds,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// and then if the machine fails to wake, 3 goodbye packets).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Number of wakeups we send if WakeOnResolve is set in the question
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Note that the announce intervals use exponential backoff, doubling each time. The probe intervals do not.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// This means that because the announce interval is doubled after sending the first packet, the first
4b22b9337f359bfd063322244f5336cc7c6ffcfars// observed on-the-wire inter-packet interval between announcements is actually one second.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// The half-second value here may be thought of as a conceptual (non-existent) half-second delay *before* the first packet is sent.
4b22b9337f359bfd063322244f5336cc7c6ffcfars#define DefaultProbeIntervalForTypeUnique (mDNSPlatformOneSecond/4)
4b22b9337f359bfd063322244f5336cc7c6ffcfars#define DefaultAnnounceIntervalForTypeShared (mDNSPlatformOneSecond/2)
4b22b9337f359bfd063322244f5336cc7c6ffcfars#define DefaultAnnounceIntervalForTypeUnique (mDNSPlatformOneSecond/2)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#define DefaultAPIntervalForRecordType(X) ((X) &kDNSRecordTypeActiveSharedMask ? DefaultAnnounceIntervalForTypeShared : \
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (X) &kDNSRecordTypeUnique ? DefaultProbeIntervalForTypeUnique : \
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (X) &kDNSRecordTypeActiveUniqueMask ? DefaultAnnounceIntervalForTypeUnique : 0)
4b22b9337f359bfd063322244f5336cc7c6ffcfars#define TimeToAnnounceThisRecord(RR,time) ((RR)->AnnounceCount && (time) - ((RR)->LastAPTime + (RR)->ThisAPInterval) >= 0)
4b22b9337f359bfd063322244f5336cc7c6ffcfars#define TimeToSendThisRecord(RR,time) ((TimeToAnnounceThisRecord(RR,time) || (RR)->ImmedAnswer) && ResourceRecordIsValidAnswer(RR))
4b22b9337f359bfd063322244f5336cc7c6ffcfars#define TicksTTL(RR) ((mDNSs32)(RR)->resrec.rroriginalttl * mDNSPlatformOneSecond)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Adjustment factor to avoid race condition (used for unicast cache entries) :
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Suppose real record has TTL of 3600, and our local caching server has held it for 3500 seconds, so it returns an aged TTL of 100.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// If we do our normal refresh at 80% of the TTL, our local caching server will return 20 seconds, so we'll do another
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// 80% refresh after 16 seconds, and then the server will return 4 seconds, and so on, in the fashion of Zeno's paradox.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// To avoid this, we extend the record's effective TTL to give it a little extra grace period.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// We adjust the 100 second TTL to 127. This means that when we do our 80% query at 102 seconds,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// the cached copy at our local caching server will already have expired, so the server will be forced
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// to fetch a fresh copy from the authoritative server, and then return a fresh record with the full TTL of 3600 seconds.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#define RRAdjustTTL(ttl) ((ttl) + ((ttl)/4) + 2)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#define RRUnadjustedTTL(ttl) ((((ttl) - 2) * 4) / 5)
4b22b9337f359bfd063322244f5336cc7c6ffcfars// SameResourceRecordSignature returns true if two resources records have the same name, type, and class, and may be sent
4b22b9337f359bfd063322244f5336cc7c6ffcfars// (or were received) on the same interface (i.e. if *both* records specify an interface, then it has to match).
4b22b9337f359bfd063322244f5336cc7c6ffcfars// TTL and rdata may differ.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// This is used for cache flush management:
4b22b9337f359bfd063322244f5336cc7c6ffcfars// When sending a unique record, all other records matching "SameResourceRecordSignature" must also be sent
4b22b9337f359bfd063322244f5336cc7c6ffcfars// When receiving a unique record, all old cache records matching "SameResourceRecordSignature" are flushed
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// SameResourceRecordNameClassInterface is functionally the same as SameResourceRecordSignature, except rrtype does not have to match
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#define SameResourceRecordSignature(A,B) (A)->resrec.rrtype == (B)->resrec.rrtype && SameResourceRecordNameClassInterface((A),(B))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool SameResourceRecordNameClassInterface(const AuthRecord *const r1, const AuthRecord *const r2)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!r1) { LogMsg("SameResourceRecordSignature ERROR: r1 is NULL"); return(mDNSfalse); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!r2) { LogMsg("SameResourceRecordSignature ERROR: r2 is NULL"); return(mDNSfalse); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome r1->resrec.InterfaceID != r2->resrec.InterfaceID) return(mDNSfalse);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SameDomainName(r1->resrec.name, r2->resrec.name));
4b22b9337f359bfd063322244f5336cc7c6ffcfars// PacketRRMatchesSignature behaves as SameResourceRecordSignature, except that types may differ if our
4b22b9337f359bfd063322244f5336cc7c6ffcfars// authoratative record is unique (as opposed to shared). For unique records, we are supposed to have
4b22b9337f359bfd063322244f5336cc7c6ffcfars// complete ownership of *all* types for this name, so *any* record type with the same name is a conflict.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// In addition, when probing we send our questions with the wildcard type kDNSQType_ANY,
4b22b9337f359bfd063322244f5336cc7c6ffcfars// so a response of any type should match, even if it is not actually the type the client plans to use.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// For now, to make it easier to avoid false conflicts, we treat SPS Proxy records like shared records,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// and require the rrtypes to match for the rdata to be considered potentially conflicting
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal mDNSBool PacketRRMatchesSignature(const CacheRecord *const pktrr, const AuthRecord *const authrr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!pktrr) { LogMsg("PacketRRMatchesSignature ERROR: pktrr is NULL"); return(mDNSfalse); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!authrr) { LogMsg("PacketRRMatchesSignature ERROR: authrr is NULL"); return(mDNSfalse); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome pktrr->resrec.InterfaceID != authrr->resrec.InterfaceID) return(mDNSfalse);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!(authrr->resrec.RecordType & kDNSRecordTypeUniqueMask) || authrr->WakeUp.HMAC.l[0])
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (pktrr->resrec.rrtype != authrr->resrec.rrtype) return(mDNSfalse);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome pktrr->resrec.rrclass == authrr->resrec.rrclass &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome pktrr->resrec.namehash == authrr->resrec.namehash &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SameDomainName(pktrr->resrec.name, authrr->resrec.name));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// CacheRecord *ka is the CacheRecord from the known answer list in the query.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// This is the information that the requester believes to be correct.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// AuthRecord *rr is the answer we are proposing to give, if not suppressed.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// This is the information that we believe to be correct.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// We've already determined that we plan to give this answer on this interface
4b22b9337f359bfd063322244f5336cc7c6ffcfars// (either the record is non-specific, or it is specific to this interface)
4b22b9337f359bfd063322244f5336cc7c6ffcfars// so now we just need to check the name, type, class, rdata and TTL.
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal mDNSBool ShouldSuppressKnownAnswer(const CacheRecord *const ka, const AuthRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If RR signature is different, or data is different, then don't suppress our answer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!IdenticalResourceRecord(&ka->resrec, &rr->resrec)) return(mDNSfalse);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the requester's indicated TTL is less than half the real TTL,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we need to give our answer before the requester's copy expires.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the requester's indicated TTL is at least half the real TTL,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then we can suppress our answer this time.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the requester's indicated TTL is greater than the TTL we believe,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then that's okay, and we don't need to do anything about it.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (If two responders on the network are offering the same information,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // that's okay, and if they are offering the information with different TTLs,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the one offering the lower TTL should defer to the one offering the higher TTL.)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome return (mDNSBool)(ka->resrec.rroriginalttl >= rr->resrec.rroriginalttl / 2);
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void SetNextAnnounceProbeTime(mDNS *const m, const AuthRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType == kDNSRecordTypeUnique)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((rr->LastAPTime + rr->ThisAPInterval) - m->timenow > mDNSPlatformOneSecond * 10)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("SetNextAnnounceProbeTime: ProbeCount %d Next in %d %s", rr->ProbeCount, (rr->LastAPTime + rr->ThisAPInterval) - m->timenow, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("SetNextAnnounceProbeTime: m->SuppressProbes %d m->timenow %d diff %d", m->SuppressProbes, m->timenow, m->SuppressProbes - m->timenow);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->NextScheduledProbe - (rr->LastAPTime + rr->ThisAPInterval) >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NextScheduledProbe = (rr->LastAPTime + rr->ThisAPInterval);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Some defensive code:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If (rr->LastAPTime + rr->ThisAPInterval) happens to be far in the past, we don't want to allow
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // NextScheduledProbe to be set excessively in the past, because that can cause bad things to happen.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // See: <rdar://problem/7795434> mDNS: Sometimes advertising stops working and record interval is set to zero
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (rr->AnnounceCount && (ResourceRecordIsValidAnswer(rr) || rr->resrec.RecordType == kDNSRecordTypeDeregistering))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->NextScheduledResponse - (rr->LastAPTime + rr->ThisAPInterval) >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NextScheduledResponse = (rr->LastAPTime + rr->ThisAPInterval);
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void InitializeLastAPTime(mDNS *const m, AuthRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For reverse-mapping Sleep Proxy PTR records, probe interval is one second
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->ThisAPInterval = rr->AddressProxy.type ? mDNSPlatformOneSecond : DefaultAPIntervalForRecordType(rr->resrec.RecordType);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // * If this is a record type that's going to probe, then we use the m->SuppressProbes time.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // * Otherwise, if it's not going to probe, but m->SuppressProbes is set because we have other
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // records that are going to probe, then we delay its first announcement so that it will
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // go out synchronized with the first announcement for the other records that *are* probing.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This is a minor performance tweak that helps keep groups of related records synchronized together.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // The addition of "interval / 2" is to make sure that, in the event that any of the probes are
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // delayed by a few milliseconds, this announcement does not inadvertently go out *before* the probing is complete.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When the probing is complete and those records begin to announce, these records will also be picked up and accelerated,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // because they will meet the criterion of being at least half-way to their scheduled announcement time.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // * If it's not going to probe and m->SuppressProbes is not already set then we should announce immediately.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we have no probe suppression time set, or it is in the past, set it now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->SuppressProbes == 0 || m->SuppressProbes - m->timenow < 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // To allow us to aggregate probes when a group of services are registered together,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the first probe is delayed 1/4 second. This means the common-case behaviour is:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1/4 second wait; probe
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1/4 second wait; probe
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1/4 second wait; probe
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1/4 second wait; announce (i.e. service is normally announced exactly one second after being registered)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->SuppressProbes = NonZeroTime(m->timenow + DefaultProbeIntervalForTypeUnique/2 + mDNSRandom(DefaultProbeIntervalForTypeUnique/2));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we already have a *probe* scheduled to go out sooner, then use that time to get better aggregation
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->SuppressProbes - m->NextScheduledProbe >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->SuppressProbes = NonZeroTime(m->NextScheduledProbe);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->SuppressProbes - m->timenow < 0) // Make sure we don't set m->SuppressProbes excessively in the past
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we already have a *query* scheduled to go out sooner, then use that time to get better aggregation
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->SuppressProbes - m->NextScheduledQuery >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->SuppressProbes = NonZeroTime(m->NextScheduledQuery);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->SuppressProbes - m->timenow < 0) // Make sure we don't set m->SuppressProbes excessively in the past
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // except... don't expect to be able to send before the m->SuppressSending timer fires
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->SuppressSending && m->SuppressProbes - m->SuppressSending < 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->SuppressProbes = NonZeroTime(m->SuppressSending);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->SuppressProbes - m->timenow > mDNSPlatformOneSecond * 8)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("InitializeLastAPTime ERROR m->SuppressProbes %d m->NextScheduledProbe %d m->NextScheduledQuery %d m->SuppressSending %d %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->SuppressProbes = NonZeroTime(m->timenow + DefaultProbeIntervalForTypeUnique/2 + mDNSRandom(DefaultProbeIntervalForTypeUnique/2));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->LastAPTime = m->SuppressProbes - rr->ThisAPInterval;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (m->SuppressProbes && m->SuppressProbes - m->timenow >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->LastAPTime = m->SuppressProbes - rr->ThisAPInterval + DefaultProbeIntervalForTypeUnique * DefaultProbeCountForTypeUnique + rr->ThisAPInterval / 2;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->LastAPTime = m->timenow - rr->ThisAPInterval;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For reverse-mapping Sleep Proxy PTR records we don't want to start probing instantly -- we
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // wait one second to give the client a chance to go to sleep, and then start our ARP/NDP probing.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // After three probes one second apart with no answer, we conclude the client is now sleeping
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and we can begin broadcasting our announcements to take over ownership of that IP address.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we don't wait for the client to go to sleep, then when the client sees our ARP Announcements there's a risk
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (depending on the OS and networking stack it's using) that it might interpret it as a conflict and change its IP address.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Set LastMCTime to now, to inhibit multicast responses
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (no need to send additional multicast responses when we're announcing anyway)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal const domainname *SetUnicastTargetToHostName(mDNS *const m, AuthRecord *rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For autotunnel services pointing at our IPv6 ULA we don't need or want a NAT mapping, but for all other
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // advertised services referencing our uDNS hostname, we want NAT mappings automatically created as appropriate,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // with the port number in our advertised SRV record automatically tracking the external mapped port.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome DomainAuthInfo *AuthInfo = GetAuthInfoForName_internal(m, rr->resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!AuthInfo || !AuthInfo->AutoTunnel) rr->AutoTarget = Target_AutoHostAndNATMAP;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // defer registration until we've got a target
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("SetUnicastTargetToHostName No target for %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("SetUnicastTargetToHostName target %##s for resource record %s", target->c, ARDisplayString(m,rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Right now this only applies to mDNS (.local) services where the target host is always m->MulticastHostname
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Eventually we should unify this with GetServiceTarget() in uDNS.c
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void SetTargetToHostName(mDNS *const m, AuthRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome domainname *const target = GetRRDomainNameTarget(&rr->resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const domainname *newname = &m->MulticastHostname;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!target) LogInfo("SetTargetToHostName: Don't know how to set the target of rrtype %s", DNSTypeName(rr->resrec.rrtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!(rr->ForceMCast || rr->ARType == AuthRecordLocalOnly || rr->ARType == AuthRecordP2P || IsLocalDomain(&rr->namestorage)))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const domainname *const n = SetUnicastTargetToHostName(m, rr);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome else { if (target) target->c[0] = 0; SetNewRData(&rr->resrec, mDNSNULL, 0); return; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("SetTargetToHostName: Target of %##s is already %##s", rr->resrec.name->c, target->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (target && !SameDomainName(target, newname))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SetNewRData(&rr->resrec, mDNSNULL, 0); // Update rdlength, rdestimate, rdatahash
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we're in the middle of probing this record, we need to start again,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // because changing its rdata may change the outcome of the tie-breaker.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (If the record type is kDNSRecordTypeUnique (unconfirmed unique) then DefaultProbeCountForRecordType is non-zero.)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->ProbeCount = DefaultProbeCountForRecordType(rr->resrec.RecordType);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we've announced this record, we really should send a goodbye packet for the old rdata before
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // changing to the new rdata. However, in practice, we only do SetTargetToHostName for unique records,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // so when we announce them we'll set the kDNSClass_UniqueRRSet and clear any stale data that way.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->RequireGoodbye && rr->resrec.RecordType == kDNSRecordTypeShared)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("Have announced shared record %##s (%s) at least once: should have sent a goodbye packet before updating",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void AcknowledgeRecord(mDNS *const m, AuthRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // CAUTION: MUST NOT do anything more with rr after calling rr->Callback(), because the client's callback function
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // is allowed to do anything, including starting/stopping queries, registering/deregistering records, etc.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void ActivateUnicastRegistration(mDNS *const m, AuthRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Make sure that we don't activate the SRV record and associated service records, if it is in
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // NoTarget state. First time when a service is being instantiated, SRV record may be in NoTarget state.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We should not activate any of the other reords (PTR, TXT) that are part of the service. When
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the target becomes available, the records will be reregistered.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("ActivateUnicastRegistration: ERROR!! Resource record %s wrong, expecting SRV type", ARDisplayString(m, srvRR));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ActivateUnicastRegistration: Found Service Record %s in state %d for %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ARDisplayString(m, srvRR), srvRR->state, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ActivateUnicastRegistration record %s in regState_NoTarget, not activating", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When we wake up from sleep, we call ActivateUnicastRegistration. It is possible that just before we went to sleep,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the service/record was being deregistered. In that case, we should not try to register again. For the cases where
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the records are deregistered due to e.g., no target for the SRV record, we would have returned from above if it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // was already in NoTarget state. If it was in the process of deregistration but did not complete fully before we went
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to sleep, then it is okay to start in Pending state as we will go back to NoTarget state if we don't have a target.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType == kDNSRecordTypeDeregistering)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ActivateUnicastRegistration: Resource record %s, current state %d, moving to DeregPending", ARDisplayString(m, rr), rr->state);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ActivateUnicastRegistration: Resource record %s, current state %d, moving to Pending", ARDisplayString(m, rr), rr->state);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->LastAPTime = m->timenow - rr->ThisAPInterval;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->expire = 0; // Forget about all the leases, start fresh
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // RestartRecordGetZoneData calls this function whenever a new interface gets registered with core.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // The records might already be registered with the server and hence could have NAT state.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_StopNATOperation_internal(m, &rr->NATinfo);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->nta) { CancelGetZoneData(m, rr->nta); rr->nta = mDNSNULL; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->tcp) { DisposeTCPConn(rr->tcp); rr->tcp = mDNSNULL; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->NextuDNSEvent - (rr->LastAPTime + rr->ThisAPInterval) >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NextuDNSEvent = (rr->LastAPTime + rr->ThisAPInterval);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Two records qualify to be local duplicates if:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// (a) the RecordTypes are the same, or
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// (b) one is Unique and the other Verified
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// (c) either is in the process of deregistering
4b22b9337f359bfd063322244f5336cc7c6ffcfars#define RecordLDT(A,B) ((A)->resrec.RecordType == (B)->resrec.RecordType || \
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ((A)->resrec.RecordType | (B)->resrec.RecordType) == (kDNSRecordTypeUnique | kDNSRecordTypeVerified) || \
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ((A)->resrec.RecordType == kDNSRecordTypeDeregistering || (B)->resrec.RecordType == kDNSRecordTypeDeregistering))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ((A)->resrec.InterfaceID == (B)->resrec.InterfaceID && RecordLDT((A),(B)) && IdenticalResourceRecord(& (A)->resrec, & (B)->resrec))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal AuthRecord *CheckAuthIdenticalRecord(AuthHash *r, AuthRecord *rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu32 slot = AuthHashSlot(rr->resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!a) return mDNSNULL;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((*rp)->resrec.RecordType == kDNSRecordTypeDeregistering)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else return *rp;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool CheckAuthRecordConflict(AuthHash *r, AuthRecord *rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu32 slot = AuthHashSlot(rr->resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!a) return mDNSfalse;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const AuthRecord *s1 = rr->RRSet ? rr->RRSet : rr;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const AuthRecord *s2 = (*rp)->RRSet ? (*rp)->RRSet : *rp;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (s1 != s2 && SameResourceRecordSignature((*rp), rr) && !IdenticalSameNameRecord(&(*rp)->resrec, &rr->resrec))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// checks to see if "rr" is already present
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal AuthRecord *CheckAuthSameRecord(AuthHash *r, AuthRecord *rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu32 slot = AuthHashSlot(rr->resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!a) return mDNSNULL;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void DecrementAutoTargetServices(mDNS *const m, AuthRecord *const rr)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // A sanity check, this should be prevented in calling code.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogInfo("DecrementAutoTargetServices: called for RRLocalOnly() record: %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!AuthRecord_uDNS(rr) && rr->resrec.rrtype == kDNSType_SRV && rr->AutoTarget == Target_AutoHost)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // If about to get rid of the last advertised service
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogInfo("DecrementAutoTargetServices: AutoTargetServices %d Record %s", m->AutoTargetServices, ARDisplayString(m, rr));
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (m->NumAllInterfaceRecords + m->NumAllInterfaceQuestions == 1)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogInfo("DecrementAutoTargetServices: NumAllInterfaceRecords %d NumAllInterfaceQuestions %d %s",
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome m->NumAllInterfaceRecords, m->NumAllInterfaceQuestions, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void IncrementAutoTargetServices(mDNS *const m, AuthRecord *const rr)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // A sanity check, this should be prevented in calling code.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogInfo("IncrementAutoTargetServices: called for RRLocalOnly() record: %s", ARDisplayString(m, rr));
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogInfo("IncrementAutoTargetServices: NumAllInterfaceRecords %d NumAllInterfaceQuestions %d %s",
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome m->NumAllInterfaceRecords, m->NumAllInterfaceQuestions, ARDisplayString(m, rr));
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (m->NumAllInterfaceRecords + m->NumAllInterfaceQuestions == 1)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (!AuthRecord_uDNS(rr) && rr->resrec.rrtype == kDNSType_SRV && rr->AutoTarget == Target_AutoHost)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogInfo("IncrementAutoTargetServices: AutoTargetServices %d Record %s", m->AutoTargetServices, ARDisplayString(m, rr));
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // If this is the first advertised service
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void getKeepaliveRaddr(mDNS *const m, AuthRecord *rr, mDNSAddr *raddr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_ExtractKeepaliveInfo(rr, &timeout, &laddr, raddr, ð, &seq, &ack, &lport, &rport, &win);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!timeout || mDNSAddressIsZero(&laddr) || mDNSAddressIsZero(raddr) || mDNSIPPortIsZero(lport) || mDNSIPPortIsZero(rport))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("getKeepaliveRaddr: not a valid record %s for keepalive %#a:%d %#a:%d", ARDisplayString(m, rr), &laddr, lport.NotAnInteger, raddr, rport.NotAnInteger);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Exported so uDNS.c can call this
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport mStatus mDNS_Register_internal(mDNS *const m, AuthRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome domainname *target = GetRRDomainNameTarget(&rr->resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome { LogMsg("mDNS_Register_internal: TTL %X should be 1 - 0x7FFFFFFF %s", rr->resrec.rroriginalttl, ARDisplayString(m, rr)); return(mStatus_BadParamErr); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome { LogMsg("mDNS_Register_internal: RecordType must be non-zero %s", ARDisplayString(m, rr)); return(mStatus_BadParamErr); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome { LogMsg("mDNS_Register_internal: Shutting down, can't register %s", ARDisplayString(m, rr)); return(mStatus_ServiceNotRunning); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->DivertMulticastAdvertisements && !AuthRecord_uDNS(rr))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSInterfaceID previousID = rr->resrec.InterfaceID;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.InterfaceID == mDNSInterface_Any || rr->resrec.InterfaceID == mDNSInterface_P2P)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.InterfaceID = mDNSInterface_LocalOnly;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.InterfaceID != mDNSInterface_LocalOnly)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome NetworkInterfaceInfo *intf = FirstInterfaceForID(m, rr->resrec.InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (intf && !intf->Advertise) { rr->resrec.InterfaceID = mDNSInterface_LocalOnly; rr->ARType = AuthRecordLocalOnly; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNS_Register_internal: Diverting record to local-only %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_Register_internal: ERROR!! Tried to register LocalOnly AuthRecord %p %##s (%s) that's already in the list",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_Register_internal: ERROR!! Tried to register AuthRecord %p %##s (%s) that's already in the list",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_Register_internal: ERROR!! Tried to register AuthRecord %p %##s (%s) that's already in the Duplicate list",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType == kDNSRecordTypeUnique)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.RecordType = kDNSRecordTypeVerified;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_Register_internal: ERROR! %##s (%s): rr->DependentOn && RecordType != kDNSRecordTypeUnique",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!(rr->DependentOn->resrec.RecordType & (kDNSRecordTypeUnique | kDNSRecordTypeVerified | kDNSRecordTypeKnownUnique)))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_Register_internal: ERROR! %##s (%s): rr->DependentOn->RecordType bad type %X",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype), rr->DependentOn->resrec.RecordType);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Field Group 1: The actual information pertaining to this resource record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Set up by client prior to call
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Field Group 2: Persistent metadata for Authoritative Records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// rr->Additional1 = set to mDNSNULL in mDNS_SetupResourceRecord; may be overridden by client
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// rr->Additional2 = set to mDNSNULL in mDNS_SetupResourceRecord; may be overridden by client
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// rr->DependentOn = set to mDNSNULL in mDNS_SetupResourceRecord; may be overridden by client
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// rr->RRSet = set to mDNSNULL in mDNS_SetupResourceRecord; may be overridden by client
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// rr->Callback = already set in mDNS_SetupResourceRecord
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// rr->Context = already set in mDNS_SetupResourceRecord
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// rr->RecordType = already set in mDNS_SetupResourceRecord
4b22b9337f359bfd063322244f5336cc7c6ffcfars// rr->HostTarget = set to mDNSfalse in mDNS_SetupResourceRecord; may be overridden by client
4b22b9337f359bfd063322244f5336cc7c6ffcfars// rr->AllowRemoteQuery = set to mDNSfalse in mDNS_SetupResourceRecord; may be overridden by client
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Make sure target is not uninitialized data, or we may crash writing debugging log messages
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->AutoTarget && target) target->c[0] = 0;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Field Group 3: Transient state for Authoritative Records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->ProbeCount = DefaultProbeCountForRecordType(rr->resrec.RecordType);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!rr->AutoTarget) InitializeLastAPTime(m, rr);
4b22b9337f359bfd063322244f5336cc7c6ffcfars// rr->LastAPTime = Set for us in InitializeLastAPTime()
4b22b9337f359bfd063322244f5336cc7c6ffcfars// rr->LastMCTime = Set for us in InitializeLastAPTime()
4b22b9337f359bfd063322244f5336cc7c6ffcfars// rr->LastMCInterface = Set for us in InitializeLastAPTime()
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For records we're holding as proxy (except reverse-mapping PTR records) two announcements is sufficient
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->WakeUp.HMAC.l[0] && !rr->AddressProxy.type) rr->AnnounceCount = 2;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Field Group 4: Transient uDNS state for Authoritative Records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome //mDNSPlatformMemZero(&rr->NATinfo, sizeof(rr->NATinfo));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We should be recording the actual internal port for this service record here. Once we initiate our NAT mapping
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // request we'll subsequently overwrite srv.port with the allocated external NAT port -- potentially multiple
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // times with different values if the external NAT port changes during the lifetime of the service registration.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome //if (rr->resrec.rrtype == kDNSType_SRV) rr->NATinfo.IntPort = rr->resrec.rdata->u.srv.port;
4b22b9337f359bfd063322244f5336cc7c6ffcfars// rr->resrec.interface = already set in mDNS_SetupResourceRecord
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// rr->resrec.name->c = MUST be set by client
4b22b9337f359bfd063322244f5336cc7c6ffcfars// rr->resrec.rrtype = already set in mDNS_SetupResourceRecord
4b22b9337f359bfd063322244f5336cc7c6ffcfars// rr->resrec.rrclass = already set in mDNS_SetupResourceRecord
4b22b9337f359bfd063322244f5336cc7c6ffcfars// rr->resrec.rroriginalttl = already set in mDNS_SetupResourceRecord
4b22b9337f359bfd063322244f5336cc7c6ffcfars// rr->resrec.rdata = MUST be set by client, unless record type is CNAME or PTR and rr->HostTarget is set
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // BIND named (name daemon) doesn't allow TXT records with zero-length rdata. This is strictly speaking correct,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // since RFC 1035 specifies a TXT record as "One or more <character-string>s", not "Zero or more <character-string>s".
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Since some legacy apps try to create zero-length TXT records, we'll silently correct it here.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.rrtype == kDNSType_TXT && rr->resrec.rdlength == 0) { rr->resrec.rdlength = 1; rr->resrec.rdata->u.txt.c[0] = 0; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SetTargetToHostName(m, rr); // Also sets rdlength and rdestimate for us, and calls InitializeLastAPTime();
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we have no target record yet, SetTargetToHostName will set rr->state == regState_NoTarget
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // In this case we leave the record half-formed in the list, and later we'll remove it from the list and re-add it properly.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Initialize the target so that we don't crash while logging etc.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome domainname *tar = GetRRDomainNameTarget(&rr->resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNS_Register_internal: record %s in NoTarget state", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rdlength = GetRDLength(&rr->resrec, mDNSfalse);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rdestimate = GetRDLength(&rr->resrec, mDNStrue);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome { LogMsg("Attempt to register record with invalid name: %s", ARDisplayString(m, rr)); return(mStatus_Invalid); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Don't do this until *after* we've set rr->resrec.rdlength
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!ValidateRData(rr->resrec.rrtype, rr->resrec.rdlength, rr->resrec.rdata))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome { LogMsg("Attempt to register record with invalid rdata: %s", ARDisplayString(m, rr)); return(mStatus_Invalid); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.namehash = DomainNameHashValue(rr->resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rdatahash = target ? DomainNameHashValue(target) : RDataHashValue(&rr->resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this is supposed to be unique, make sure we don't have any name conflicts.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we found a conflict, we may still want to insert the record in the list but mark it appropriately
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (kDNSRecordTypeDeregistering) so that we deliver RMV events to the application. But this causes more
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // complications and not clear whether there are any benefits. See rdar:9304275 for details.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Hence, just bail out.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // This comment is doesn’t make any sense. -- SC
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNS_Register_internal: Name conflict %s (%p), InterfaceID %p", ARDisplayString(m, rr), rr, rr->resrec.InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For uDNS records, we don't support duplicate checks at this time.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!m->NewLocalRecords) m->NewLocalRecords = rr;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When we called SetTargetToHostName, it may have caused mDNS_Register_internal to be re-entered, appending new
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // records to the list, so we now need to update p to advance to the new end to the list before appending our new record.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note that for AutoTunnel this should never happen, but this check makes the code future-proof.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (*p) p=&(*p)->next;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType == kDNSRecordTypeUnique) rr->resrec.RecordType = kDNSRecordTypeVerified;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->state != regState_NoTarget) ActivateUnicastRegistration(m, rr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome return(mStatus_NoError); // <--- Note: For unicast records, code currently bails out at this point
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Now that we've finished building our new record, make sure it's not identical to one we already have
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (r->resrec.RecordType == kDNSRecordTypeDeregistering) r->AnnounceCount = 0;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_Register_internal:Adding to duplicate list %s", ARDisplayString(m,rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the previous copy of this record is already verified unique,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then indicate that we should move this record promptly to kDNSRecordTypeUnique state.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Setting ProbeCount to zero will cause SendQueries() to advance this record to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // kDNSRecordTypeVerified state and call the client callback at the next appropriate time.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType == kDNSRecordTypeUnique && r->resrec.RecordType == kDNSRecordTypeVerified)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_Register_internal: Adding to active record list %s", ARDisplayString(m,rr));
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // No probing for LocalOnly records; acknowledge them right away
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType == kDNSRecordTypeUnique) rr->resrec.RecordType = kDNSRecordTypeVerified;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!m->NewLocalRecords) m->NewLocalRecords = rr;
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // If this is a non-sleep proxy keepalive record, fetch the MAC address of the remote host.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This is used by the in-NIC proxy to send the keepalive packets.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (!rr->WakeUp.HMAC.l[0] && mDNS_KeepaliveRecord(&rr->resrec))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Set the record type to known unique to prevent probing keep alive records.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Also make sure we do not announce the keepalive records.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.RecordType = kDNSRecordTypeKnownUnique;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This is an asynchronous call. Once the remote MAC address is available, helper will schedule an
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // asynchronous task to update the resource record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!AuthRecord_uDNS(rr)) // This check is superfluous, given that for unicast records we (currently) bail out above
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // We have inserted the record in the list. See if we have to advertise the A/AAAA, HINFO, PTR records.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For records that are not going to probe, acknowledge them right away
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType != kDNSRecordTypeUnique && rr->resrec.RecordType != kDNSRecordTypeDeregistering)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Adding a record may affect whether or not we should sleep
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void RecordProbeFailure(mDNS *const m, const AuthRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we've had fifteen or more probe failures, rate-limit to one every five seconds.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If a bunch of hosts have all been configured with the same name, then they'll all
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // conflict and run through the same series of names: name-2, name-3, name-4, etc.,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // up to name-10. After that they'll start adding random increments in the range 1-100,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // so they're more likely to branch out in the available namespace and settle on a set of
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // unique names quickly. If after five more tries the host is still conflicting, then we
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // may have a serious problem, so we start rate-limiting so we don't melt down the network.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->SuppressProbes = NonZeroTime(m->timenow + mDNSPlatformOneSecond * 5);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("Excessive name conflicts (%lu) for %##s (%s); rate limiting in effect",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NumFailedProbes, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void CompleteRDataUpdate(mDNS *const m, AuthRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SetNewRData(&rr->resrec, rr->NewRData, rr->newrdlength); // Update our rdata
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->NewRData = mDNSNULL; // Clear the NewRData pointer ...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->UpdateCallback(m, rr, OldRData, OldRDLen); // ... and let the client know
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Note: mDNS_Deregister_internal can call a user callback, which may change the record list and/or question list.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Exported so uDNS.c can call this
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport mStatus mDNS_Deregister_internal(mDNS *const m, AuthRecord *const rr, mDNS_Dereg_type drt)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AuthRecord **p = &m->ResourceRecords; // Find this record in our list of active records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu32 slot = AuthHashSlot(rr->resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome a = AuthGroupForRecord(&m->rrauth, slot, &rr->resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!a) return mDNSfalse;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We found our record on the main list. See if there are any duplicates that need special handling.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (drt == mDNS_Dereg_conflict) // If this was a conflict, see that all duplicates get the same treatment
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Scan for duplicates of rr, and mark them for deregistration at the end of this routine, after we've finished
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // deregistering rr. We need to do this scan *before* we give the client the chance to free and reuse the rr memory.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (r2 = m->DuplicateRecords; r2; r2=r2->next) if (RecordIsLocalDuplicate(r2, rr)) r2->ProbeCount = 0xFF;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Before we delete the record (and potentially send a goodbye packet)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // first see if we have a record on the duplicate list ready to take over from it.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (*d && !RecordIsLocalDuplicate(*d, rr)) d=&(*d)->next;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_Register_internal: Duplicate record %p taking over from %p %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome dup, rr, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *d = dup->next; // Cut replacement record from DuplicateRecords list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!InsertAuthRecord(m, &m->rrauth, dup)) LogMsg("mDNS_Deregister_internal: ERROR!! cannot insert %s", ARDisplayString(m, dup));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->next = dup; // ... splice it in right after the record we're about to delete
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome dup->resrec.RecordType = rr->resrec.RecordType;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome dup->ProbeRestartCount = rr->ProbeRestartCount;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We didn't find our record on the main list; try the DuplicateRecords list instead.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we found our record on the duplicate list, then make sure we don't send a goodbye for it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Duplicate records are not used for sending wakeups or goodbyes. Hence, deregister them
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // immediately. When there is a conflict, we deregister all the conflicting duplicate records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // also that have been marked above in this function. In that case, we come here and if we don't
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // deregister (unilink from the DuplicateRecords list), we will be recursing infinitely. Hence,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // clear the HMAC which will cause it to deregister. See <rdar://problem/10380988> for
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.RecordType = kDNSRecordTypeDeregistering;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (*p) debugf("mDNS_Deregister_internal: Deleting DuplicateRecord %p %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // No need to log an error message if we already know this is a potentially repeated deregistration
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_Deregister_internal: Record %p not found in list %s", rr, ARDisplayString(m,rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this is a shared record and we've announced it at least once,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we need to retract that announcement before we delete the record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this is a record (including mDNSInterface_LocalOnly records) for which we've given local-only answers then
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // it's tempting to just do "AnswerAllLocalQuestionsWithLocalAuthRecord(m, rr, mDNSfalse)" here, but that would not not be safe.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // The AnswerAllLocalQuestionsWithLocalAuthRecord routine walks the question list invoking client callbacks, using the "m->CurrentQuestion"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // mechanism to cope with the client callback modifying the question list while that's happening.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // However, mDNS_Deregister could have been called from a client callback (e.g. from the domain enumeration callback FoundDomain)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // which means that the "m->CurrentQuestion" mechanism is already in use to protect that list, so we can't use it twice.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // More generally, if we invoke callbacks from within a client callback, then those callbacks could deregister other
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // records, thereby invoking yet more callbacks, without limit.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // The solution is to defer delivering the "Remove" events until mDNS_Execute time, just like we do for sending
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // actual goodbye packets.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->tcp) { DisposeTCPConn(rr->tcp); rr->tcp = mDNSNULL; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.RecordType = kDNSRecordTypeDeregistering;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // At this point unconditionally we bail out
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Either uDNS_DeregisterRecord will have completed synchronously, and called CompleteDeregistration,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // which calls us back here with RequireGoodbye set to false, or it will have initiated the deregistration
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // process and will complete asynchronously. Either way we don't need to do anything more here.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Sometimes the records don't complete proper deregistration i.e., don't wait for a response
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // from the server. In that case, if the records have been part of a group update, clear the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // state here. Some recors e.g., AutoTunnel gets reused without ever being completely initialized
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We defer cleaning up NAT state only after sending goodbyes. This is important because
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // RecordRegistrationGotZoneData guards against creating NAT state if clientContext is non-NULL.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This happens today when we turn on/off interface where we get multiple network transitions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and RestartRecordGetZoneData triggers re-registration of the resource records even though
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // they may be in Registered state which causes NAT information to be setup multiple times. Defering
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the cleanup here keeps clientContext non-NULL and hence prevents that. Note that cleaning up
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // NAT state here takes care of the case where we did not send goodbyes at all.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_StopNATOperation_internal(m, &rr->NATinfo);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->nta) { CancelGetZoneData(m, rr->nta); rr->nta = mDNSNULL; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->tcp) { DisposeTCPConn(rr->tcp); rr->tcp = mDNSNULL; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // UNICAST_DISABLED
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_Deregister_internal: %s already marked kDNSRecordTypeUnregistered", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (RecordType == kDNSRecordTypeDeregistering)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_Deregister_internal: %s already marked kDNSRecordTypeDeregistering", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // <rdar://problem/7457925> Local-only questions don't get remove events for unique records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We may want to consider changing this code so that we generate local-only question "rmv"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // events (and maybe goodbye packets too) for unique records as well as for shared records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: If we change the logic for this "if" statement, need to ensure that the code in
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // CompleteDeregistration() sets the appropriate state variables to gaurantee that "else"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // clause will execute here and the record will be cut from the list.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (RecordType == kDNSRecordTypeShared && (rr->RequireGoodbye || rr->AnsweredLocalQ)))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome verbosedebugf("mDNS_Deregister_internal: Starting deregistration for %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.RecordType = kDNSRecordTypeDeregistering;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->AnnounceCount = rr->WakeUp.HMAC.l[0] ? WakeupCount : (drt == mDNS_Dereg_rapid) ? 1 : GoodbyeCount;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->ThisAPInterval = mDNSPlatformOneSecond * 2;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->LastAPTime = m->timenow - rr->ThisAPInterval;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->NextScheduledResponse - (m->timenow + mDNSPlatformOneSecond/10) >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NextScheduledResponse = (m->timenow + mDNSPlatformOneSecond/10);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AuthGroup *ag = RemoveAuthRecord(m, &m->rrauth, rr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ag->NewLocalOnlyRecords == rr) ag->NewLocalOnlyRecords = rr->next;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *p = rr->next; // Cut this record from the list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->NewLocalRecords == rr) m->NewLocalRecords = rr->next;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If someone is about to look at this, bump the pointer forward
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentRecord == rr) m->CurrentRecord = rr->next;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Should we generate local remove events here?
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // i.e. something like:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // if (rr->AnsweredLocalQ) { AnswerAllLocalQuestionsWithLocalAuthRecord(m, rr, mDNSfalse); rr->AnsweredLocalQ = mDNSfalse; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome verbosedebugf("mDNS_Deregister_internal: Deleting record for %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.RecordType = kDNSRecordTypeUnregistered;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((drt == mDNS_Dereg_conflict || drt == mDNS_Dereg_repeat) && RecordType == kDNSRecordTypeShared)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_Deregister_internal: Cannot have a conflict on a shared record! %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we have an update queued up which never executed, give the client a chance to free that memory
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->NewRData) CompleteRDataUpdate(m, rr); // Update our rdata, clear the NewRData pointer, and return memory to the client
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // CAUTION: MUST NOT do anything more with rr after calling rr->Callback(), because the client's callback function
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // is allowed to do anything, including starting/stopping queries, registering/deregistering records, etc.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // In this case the likely client action to the mStatus_MemFree message is to free the memory,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // so any attempt to touch rr after this is likely to lead to a crash.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNS_Deregister_internal: mStatus_MemFree for %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->RecordCallback(m, rr, mStatus_MemFree); // MUST NOT touch rr after this
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->RecordCallback(m, rr, mStatus_NameConflict); // MUST NOT touch rr after this
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Now that we've finished deregistering rr, check our DuplicateRecords list for any that we marked previously.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note that with all the client callbacks going on, by the time we get here all the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // records we marked may have been explicitly deregistered by the client anyway.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Deregister_internal(m, r2, mDNS_Dereg_conflict);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // As this is a duplicate record, it will be unlinked from the list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // immediately
4b22b9337f359bfd063322244f5336cc7c6ffcfars// ***************************************************************************
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void AddRecordToResponseList(AuthRecord ***nrpp, AuthRecord *rr, AuthRecord *add)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->NextResponse == mDNSNULL && *nrpp != &rr->NextResponse)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // NR_AdditionalTo must point to a record with NR_AnswerTo set (and not NR_AdditionalTo)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If 'add' does not meet this requirement, then follow its NR_AdditionalTo pointer to a record that does
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // The referenced record will definitely be acceptable (by recursive application of this rule)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (add && add->NR_AdditionalTo) add = add->NR_AdditionalTo;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("AddRecordToResponseList: %##s (%s) already in list", rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void AddAdditionalsToResponseList(mDNS *const m, AuthRecord *ResponseRecords, AuthRecord ***nrpp, const mDNSInterfaceID InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr=ResponseRecords; rr; rr=rr->NextResponse) // For each record we plan to put
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (Note: This is an "if", not a "while". If we add a record, we'll find it again
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // later in the "for" loop, and we will follow further "additional" links then.)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->Additional1 && ResourceRecordIsValidInterfaceAnswer(rr->Additional1, InterfaceID))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AddRecordToResponseList(nrpp, rr->Additional1, rr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->Additional2 && ResourceRecordIsValidInterfaceAnswer(rr->Additional2, InterfaceID))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AddRecordToResponseList(nrpp, rr->Additional2, rr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For SRV records, automatically add the Address record(s) for the target host
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr2=m->ResourceRecords; rr2; rr2=rr2->next) // Scan list of resource records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (RRTypeIsAddressType(rr2->resrec.rrtype) && // For all address records (A/AAAA) ...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ResourceRecordIsValidInterfaceAnswer(rr2, InterfaceID) && // ... which are valid for answer ...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rdatahash == rr2->resrec.namehash && // ... whose name is the name of the SRV target
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SameDomainName(&rr->resrec.rdata->u.srv.target, rr2->resrec.name))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (RRTypeIsAddressType(rr->resrec.rrtype)) // For A or AAAA, put counterpart as additional
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr2=m->ResourceRecords; rr2; rr2=rr2->next) // Scan list of resource records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (RRTypeIsAddressType(rr2->resrec.rrtype) && // For all address records (A/AAAA) ...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ResourceRecordIsValidInterfaceAnswer(rr2, InterfaceID) && // ... which are valid for answer ...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.namehash == rr2->resrec.namehash && // ... and have the same name
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SameDomainName(rr->resrec.name, rr2->resrec.name))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (rr->resrec.rrtype == kDNSType_PTR) // For service PTR, see if we want to add DeviceInfo record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ResourceRecordIsValidInterfaceAnswer(&m->DeviceInfo, InterfaceID) &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SameDomainLabel(rr->resrec.rdata->u.name.c, m->DeviceInfo.resrec.name->c))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AddRecordToResponseList(nrpp, &m->DeviceInfo, rr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal int AnonInfoSpace(AnonymousInfo *info)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2 bytes for compressed name + type (2) class (2) TTL (4) rdlength (2) rdata (n)
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void SendDelayedUnicastResponse(mDNS *const m, const mDNSAddr *const dest, const mDNSInterfaceID InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome NetworkInterfaceInfo *intf = FirstInterfaceForID(m, InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Make a list of all our records that need to be unicast to this destination
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we find we can no longer unicast this answer, clear ImmedUnicast
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSSameIPv4Address(rr->v4Requester, onesIPv4Addr) ||
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSSameIPv6Address(rr->v6Requester, onesIPv6Addr) )
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->ImmedUnicast && rr->ImmedAnswer == InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((dest->type == mDNSAddrType_IPv4 && mDNSSameIPv4Address(rr->v4Requester, dest->ip.v4)) ||
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (dest->type == mDNSAddrType_IPv6 && mDNSSameIPv6Address(rr->v6Requester, dest->ip.v6)))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->ImmedAnswer = mDNSNULL; // Clear the state fields
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Only sent records registered for P2P over P2P interfaces
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (intf && !mDNSPlatformValidRecordForInterface(rr, intf))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("SendDelayedUnicastResponse: Not sending %s, on %s", ARDisplayString(m, rr), InterfaceNameForID(m, InterfaceID));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->NextResponse == mDNSNULL && nrp != &rr->NextResponse) // rr->NR_AnswerTo
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AddAdditionalsToResponseList(m, ResponseRecords, &nrp, InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome InitializeDNSMessage(&m->omsg.h, zeroID, ResponseFlags);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Put answers in the packet
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (ResponseRecords && ResponseRecords->NR_AnswerTo)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnoninfoSpace += AnonInfoSpace(rr->resrec.AnonInfo);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.AnonInfo->SendNow = mDNSInterfaceMark;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rrclass |= kDNSClass_UniqueRRSet; // Temporarily set the cache flush bit so PutResourceRecord will set it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Retract the limit by AnoninfoSpace which we need to put the AnoInfo option.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome newptr = PutResourceRecordTTLWithLimit(&m->omsg, responseptr, &m->omsg.h.numAnswers, &rr->resrec, rr->resrec.rroriginalttl,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->omsg.data + (AllowedRRSpace(&m->omsg) - AnoninfoSpace));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rrclass &= ~kDNSClass_UniqueRRSet; // Make sure to clear cache flush bit back to normal state
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome break; // If packet full, send it now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We have reserved the space for AnonInfo option. PutResourceRecord uses the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // standard limit (AllowedRRSpace) and we should have space now.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.AnonInfo && rr->resrec.AnonInfo->SendNow == mDNSInterfaceMark)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ResourceRecord *nsec3RR = rr->resrec.AnonInfo->nsec3RR;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome newptr = PutResourceRecord(&m->omsg, responseptr, &m->omsg.h.numAuthorities, nsec3RR);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("SendDelayedUnicastResponse: Added NSEC3 Record %s on %p", RRDisplayString(m, nsec3RR), intf->InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We allocated space and we should not fail. Don't break, we need to clear the SendNow flag.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("SendDelayedUnicastResponse: ERROR!! Cannot Add NSEC3 Record %s on %p", RRDisplayString(m, nsec3RR), intf->InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Add additionals, if there's space
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (ResponseRecords && !ResponseRecords->NR_AnswerTo)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rrclass |= kDNSClass_UniqueRRSet; // Temporarily set the cache flush bit so PutResourceRecord will set it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome newptr = PutResourceRecord(&m->omsg, responseptr, &m->omsg.h.numAdditionals, &rr->resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rrclass &= ~kDNSClass_UniqueRRSet; // Make sure to clear cache flush bit back to normal state
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (newptr && m->omsg.h.numAnswers) rr->RequireGoodbye = mDNStrue;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask) rr->ImmedAnswer = mDNSInterfaceMark;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSSendDNSMessage(m, &m->omsg, responseptr, InterfaceID, mDNSNULL, dest, MulticastDNSPort, mDNSNULL, mDNSNULL, mDNSfalse);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// CompleteDeregistration guarantees that on exit the record will have been cut from the m->ResourceRecords list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// and the client's mStatus_MemFree callback will have been invoked
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void CompleteDeregistration(mDNS *const m, AuthRecord *rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("CompleteDeregistration: called for Resource record %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Clearing rr->RequireGoodbye signals mDNS_Deregister_internal() that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // it should go ahead and immediately dispose of this registration
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->AnsweredLocalQ) { AnswerAllLocalQuestionsWithLocalAuthRecord(m, rr, QC_rmv); rr->AnsweredLocalQ = mDNSfalse; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal); // Don't touch rr after this
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// DiscardDeregistrations is used on shutdown and sleep to discard (forcibly and immediately)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// any deregistering records that remain in the m->ResourceRecords list.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// DiscardDeregistrations calls mDNS_Deregister_internal which can call a user callback,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// which may change the record list and/or question list.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("DiscardDeregistrations ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!AuthRecord_uDNS(rr) && rr->resrec.RecordType == kDNSRecordTypeDeregistering)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CompleteDeregistration(m, rr); // Don't touch rr after this
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mStatus GetLabelDecimalValue(const mDNSu8 *const src, mDNSu8 *dst)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (src[0] < 1 || src[0] > 3) return(mStatus_Invalid);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (src[i] < '0' || src[i] > '9') return(mStatus_Invalid);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mStatus GetIPv4FromName(mDNSAddr *const a, const domainname *const name)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (skip < 0) { LogMsg("GetIPFromName: Need six labels in IPv4 reverse mapping name %##s", name); return mStatus_Invalid; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (GetLabelDecimalValue(SkipLeadingLabels(name, skip+3)->c, &a->ip.v4.b[0]) ||
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome GetLabelDecimalValue(SkipLeadingLabels(name, skip+2)->c, &a->ip.v4.b[1]) ||
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome GetLabelDecimalValue(SkipLeadingLabels(name, skip+1)->c, &a->ip.v4.b[2]) ||
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome GetLabelDecimalValue(SkipLeadingLabels(name, skip+0)->c, &a->ip.v4.b[3])) return mStatus_Invalid;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#define HexVal(X) ( ((X) >= '0' && (X) <= '9') ? ((X) - '0' ) : \
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ((X) >= 'A' && (X) <= 'F') ? ((X) - 'A' + 10) : \
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ((X) >= 'a' && (X) <= 'f') ? ((X) - 'a' + 10) : -1)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mStatus GetIPv6FromName(mDNSAddr *const a, const domainname *const name)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome int i, h, l;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (skip < 0) { LogMsg("GetIPFromName: Need 34 labels in IPv6 reverse mapping name %##s", name); return mStatus_Invalid; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<16; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (l<0 || h<0) return mStatus_Invalid;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSs32 ReverseMapDomainType(const domainname *const name)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const domainname *suffix = SkipLeadingLabels(name, skip);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SameDomainName(suffix, (const domainname*)"\x7" "in-addr" "\x4" "arpa")) return mDNSAddrType_IPv4;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SameDomainName(suffix, (const domainname*)"\x3" "ip6" "\x4" "arpa")) return mDNSAddrType_IPv6;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void SendARP(mDNS *const m, const mDNSu8 op, const AuthRecord *const rr,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSv4Addr *const spa, const mDNSEthAddr *const tha, const mDNSv4Addr *const tpa, const mDNSEthAddr *const dst)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome NetworkInterfaceInfo *intf = FirstInterfaceForID(m, rr->resrec.InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!intf) { LogMsg("SendARP: No interface with InterfaceID %p found %s", rr->resrec.InterfaceID, ARDisplayString(m,rr)); return; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x00 Destination address
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x06 Source address (Note: Since we don't currently set the BIOCSHDRCMPLT option, BPF will fill in the real interface address for us)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x0C ARP Ethertype (0x0806)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x0E ARP header
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *ptr++ = 0x00; *ptr++ = 0x01; // Hardware address space; Ethernet = 1
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *ptr++ = 0x08; *ptr++ = 0x00; // Protocol address space; IP = 0x0800
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *ptr++ = 0x00; *ptr++ = op; // opcode; Request = 1, Response = 2
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x16 Sender hardware address (our MAC address)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x1C Sender protocol address
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x20 Target hardware address
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x26 Target protocol address
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x2A Total ARP Packet length 42 bytes
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformSendRawPacket(m->omsg.data, ptr, rr->resrec.InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSu16 CheckSum(const void *const data, mDNSs32 length, mDNSu32 sum)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (length > 0) { length -= 2; sum += *ptr++; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSu16 IPv6CheckSum(const mDNSv6Addr *const src, const mDNSv6Addr *const dst, const mDNSu8 protocol, const void *const data, const mDNSu32 length)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome return CheckSum(&ph, sizeof(ph), CheckSum(data, length, 0));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void SendNDP(mDNS *const m, const mDNSu8 op, const mDNSu8 flags, const AuthRecord *const rr,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSv6Addr *const spa, const mDNSEthAddr *const tha, const mDNSv6Addr *const tpa, const mDNSEthAddr *const dst)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Some recipient hosts seem to ignore Neighbor Solicitations if the IPv6-layer destination address is not the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // appropriate IPv6 solicited node multicast address, so we use that IPv6-layer destination address, even though
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // at the Ethernet-layer we unicast the packet to the intended target, to avoid wasting network bandwidth.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSv6Addr mc = { { 0xFF,0x02,0x00,0x00, 0,0,0,0, 0,0,0,1, 0xFF,tpa->b[0xD],tpa->b[0xE],tpa->b[0xF] } };
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSv6Addr *const v6dst = (op == NDP_Sol) ? &mc : tpa;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome NetworkInterfaceInfo *intf = FirstInterfaceForID(m, rr->resrec.InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!intf) { LogMsg("SendNDP: No interface with InterfaceID %p found %s", rr->resrec.InterfaceID, ARDisplayString(m,rr)); return; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x00 Destination address
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Right now we only send Neighbor Solicitations to verify whether the host we're proxying for has gone to sleep yet.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Since we know who we're looking for, we send it via Ethernet-layer unicast, rather than bothering every host on the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // link with a pointless link-layer multicast.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Should we want to send traditional Neighbor Solicitations in the future, where we really don't know in advance what
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Ethernet-layer address we're looking for, we'll need to send to the appropriate Ethernet-layer multicast address:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *ptr++ = 0x33;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *ptr++ = 0x33;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *ptr++ = 0xFF;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *ptr++ = tpa->b[0xD];
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *ptr++ = tpa->b[0xE];
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *ptr++ = tpa->b[0xF];
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x06 Source address (Note: Since we don't currently set the BIOCSHDRCMPLT option, BPF will fill in the real interface address for us)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<6; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x0C IPv6 Ethertype (0x86DD)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x0E IPv6 header
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *ptr++ = 0x60; *ptr++ = 0x00; *ptr++ = 0x00; *ptr++ = 0x00; // Version, Traffic Class, Flow Label
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x16 Sender IPv6 address
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x26 Destination IPv6 address
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x36 NDP header
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *ptr++ = op; // 0x87 == Neighbor Solicitation, 0x88 == Neighbor Advertisement
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *ptr++ = 0x00; *ptr++ = 0x00; // Checksum placeholder (0x38, 0x39)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (op == NDP_Sol) // Neighbor Solicitation. The NDP "target" is the address we seek.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x3E NDP target.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x4E Source Link-layer Address
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // MUST NOT be included when the source IP address is the unspecified address.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Otherwise, on link layers that have addresses this option MUST be included
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // in multicast solicitations and SHOULD be included in unicast solicitations.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *ptr++ = NDP_SrcLL; // Option Type 1 == Source Link-layer Address
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *ptr++ = 0x01; // Option length 1 (in units of 8 octets)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<6; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else // Neighbor Advertisement. The NDP "target" is the address we're giving information about.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x3E NDP target.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x4E Target Link-layer Address
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *ptr++ = NDP_TgtLL; // Option Type 2 == Target Link-layer Address
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *ptr++ = 0x01; // Option length 1 (in units of 8 octets)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<6; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x4E or 0x56 Total NDP Packet length 78 or 86 bytes
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->omsg.data[0x13] = ptr - &m->omsg.data[0x36]; // Compute actual length
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome checksum.NotAnInteger = ~IPv6CheckSum(spa, v6dst, 0x3A, &m->omsg.data[0x36], m->omsg.data[0x13]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformSendRawPacket(m->omsg.data, ptr, rr->resrec.InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void SetupTracerOpt(const mDNS *const m, rdataOPT *const Trace)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void SetupOwnerOpt(const mDNS *const m, const NetworkInterfaceInfo *const intf, rdataOPT *const owner)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Don't try to compute the optlen until *after* we've set up the data fields
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Right now the DNSOpt_Owner_Space macro does not depend on the owner->u.owner being set up correctly, but in the future it might
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome owner->optlen = DNSOpt_Owner_Space(&m->PrimaryMAC, &intf->MAC) - 4;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (++rr->UpdateCredits >= kMaxUpdateCredits) rr->NextUpdateCredit = 0;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else rr->NextUpdateCredit = NonZeroTime(rr->NextUpdateCredit + kUpdateCreditRefreshInterval);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool ShouldSendGoodbyesBeforeSleep(mDNS *const m, const NetworkInterfaceInfo *intf, AuthRecord *rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If there are no sleep proxies, we set the state to SleepState_Sleeping explicitly
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and hence there is no need to check for Transfering state. But if we have sleep
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // proxies and partially sending goodbyes for some records, we will be in Transfering
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // state and hence need to make sure that we send goodbyes in that case too. Checking whether
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we are not awake handles both cases.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((rr->AuthFlags & AuthFlagsWakeOnly) && (m->SleepState != SleepState_Awake))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("ShouldSendGoodbyesBeforeSleep: marking for goodbye", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we are going to sleep and in SleepState_Sleeping, SendGoodbyes on the interface tell you
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // whether you can send goodbyes or not.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("ShouldSendGoodbyesBeforeSleep: not sending goodbye %s, int %p", ARDisplayString(m, rr), intf->InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("ShouldSendGoodbyesBeforeSleep: sending goodbye %s, int %p", ARDisplayString(m, rr), intf->InterfaceID);
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Note about acceleration of announcements to facilitate automatic coalescing of
4b22b9337f359bfd063322244f5336cc7c6ffcfars// multiple independent threads of announcements into a single synchronized thread:
4b22b9337f359bfd063322244f5336cc7c6ffcfars// The announcements in the packet may be at different stages of maturity;
4b22b9337f359bfd063322244f5336cc7c6ffcfars// One-second interval, two-second interval, four-second interval, and so on.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// After we've put in all the announcements that are due, we then consider
4b22b9337f359bfd063322244f5336cc7c6ffcfars// whether there are other nearly-due announcements that are worth accelerating.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// To be eligible for acceleration, a record MUST NOT be older (further along
4b22b9337f359bfd063322244f5336cc7c6ffcfars// its timeline) than the most mature record we've already put in the packet.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// In other words, younger records can have their timelines accelerated to catch up
4b22b9337f359bfd063322244f5336cc7c6ffcfars// with their elder bretheren; this narrows the age gap and helps them eventually get in sync.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Older records cannot have their timelines accelerated; this would just widen
4b22b9337f359bfd063322244f5336cc7c6ffcfars// the gap between them and their younger bretheren and get them even more out of sync.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Note: SendResponses calls mDNS_Deregister_internal which can call a user callback, which may change
4b22b9337f359bfd063322244f5336cc7c6ffcfars// the record list and/or question list.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const NetworkInterfaceInfo *intf = GetFirstActiveInterface(m->HostInterfaces);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NextScheduledResponse = m->timenow + 0x78000000;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->SleepState == SleepState_Transferring) RetrySPSRegistrations(m);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!mDNSIPv4AddressIsZero(rr->v4Requester)) SendDelayedUnicastResponse(m, &v4, rr->ImmedAnswer);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!mDNSIPv6AddressIsZero(rr->v6Requester)) SendDelayedUnicastResponse(m, &v6, rr->ImmedAnswer);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("SendResponses: ERROR: rr->ImmedUnicast still set: %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *** 1. Setup: Set the SendRNow and ImmedAnswer fields to indicate which interface(s) the records need to be sent on
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Run through our list of records, and decide which ones we're going to announce on all interfaces
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (rr->NextUpdateCredit && m->timenow - rr->NextUpdateCredit >= 0) GrantUpdateCredit(rr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType == kDNSRecordTypeDeregistering)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->AnnounceCount) rr->ImmedAnswer = mDNSInterfaceMark; // Send goodbye packet on all interfaces
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("SendResponses: Sending wakeup %2d for %.6a %s", rr->AnnounceCount-3, &rr->WakeUp.IMAC, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SendWakeup(m, rr->resrec.InterfaceID, &rr->WakeUp.IMAC, &rr->WakeUp.password);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if ((r2->resrec.RecordType == kDNSRecordTypeDeregistering) && r2->AnnounceCount && (r2->resrec.InterfaceID == rr->resrec.InterfaceID) &&
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome mDNSSameEthAddress(&r2->WakeUp.IMAC, &rr->WakeUp.IMAC) && !mDNSSameEthAddress(&zeroEthAddr, &r2->WakeUp.HMAC))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For now we only want to send a single Unsolicited Neighbor Advertisement restoring the address to the original
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // owner, because these packets can cause some IPv6 stacks to falsely conclude that there's an address conflict.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (r2->AddressProxy.type == mDNSAddrType_IPv6 && r2->AnnounceCount == WakeupCount)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("NDP Announcement %2d Releasing traffic for H-MAC %.6a I-MAC %.6a %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome r2->AnnounceCount-3, &r2->WakeUp.HMAC, &r2->WakeUp.IMAC, ARDisplayString(m,r2));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SendNDP(m, NDP_Adv, NDP_Override, r2, &r2->AddressProxy.ip.v6, &r2->WakeUp.IMAC, &AllHosts_v6, &AllHosts_v6_Eth);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // After 15 wakeups without success (maybe host has left the network) send three goodbyes instead
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (--r2->AnnounceCount <= GoodbyeCount) r2->WakeUp.HMAC = zeroEthAddr;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!mDNSSameEthAddress(&zeroEthAddr, &rr->WakeUp.HMAC))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->AddressProxy.type == mDNSAddrType_IPv4)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("ARP Announcement %2d Capturing traffic for H-MAC %.6a I-MAC %.6a %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->AnnounceCount, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m,rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SendARP(m, 1, rr, &rr->AddressProxy.ip.v4, &zeroEthAddr, &rr->AddressProxy.ip.v4, &onesEthAddr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (rr->AddressProxy.type == mDNSAddrType_IPv6)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("NDP Announcement %2d Capturing traffic for H-MAC %.6a I-MAC %.6a %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->AnnounceCount, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m,rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SendNDP(m, NDP_Adv, NDP_Override, rr, &rr->AddressProxy.ip.v6, mDNSNULL, &AllHosts_v6, &AllHosts_v6_Eth);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->ImmedAnswer = mDNSInterfaceMark; // Send on all interfaces
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (maxExistingAnnounceInterval < rr->ThisAPInterval)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome maxExistingAnnounceInterval = rr->ThisAPInterval;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Any interface-specific records we're going to send are marked as being sent on all appropriate interfaces (which is just one)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Eligible records that are more than half-way to their announcement time are accelerated
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((rr->resrec.InterfaceID && rr->ImmedAnswer) ||
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (rr->ThisAPInterval <= maxExistingAnnounceInterval &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome TimeToAnnounceThisRecord(rr, m->timenow + rr->ThisAPInterval/2) &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome !rr->AddressProxy.type && // Don't include ARP Annoucements when considering which records to accelerate
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->ImmedAnswer = mDNSInterfaceMark; // Send on all interfaces
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When sending SRV records (particularly when announcing a new service) automatically add related Address record(s) as additionals
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: Currently all address records are interface-specific, so it's safe to set ImmedAdditional to their InterfaceID,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // which will be non-null. If by some chance there is an address record that's not interface-specific (should never happen)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then all that means is that it won't get sent -- which would not be the end of the world.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->ImmedAnswer && rr->resrec.rrtype == kDNSType_SRV)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (r2=m->ResourceRecords; r2; r2=r2->next) // Scan list of resource records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (RRTypeIsAddressType(r2->resrec.rrtype) && // For all address records (A/AAAA) ...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ResourceRecordIsValidAnswer(r2) && // ... which are valid for answer ...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->LastMCTime - r2->LastMCTime >= 0 && // ... which we have not sent recently ...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rdatahash == r2->resrec.namehash && // ... whose name is the name of the SRV target
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SameDomainName(&rr->resrec.rdata->u.srv.target, r2->resrec.name) &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (rr->ImmedAnswer == mDNSInterfaceMark || rr->ImmedAnswer == r2->resrec.InterfaceID))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome r2->ImmedAdditional = r2->resrec.InterfaceID; // ... then mark this address record for sending too
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We also make sure we send the DeviceInfo TXT record too, if necessary
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We check for RecordType == kDNSRecordTypeShared because we don't want to tag the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // DeviceInfo TXT record onto a goodbye packet (RecordType == kDNSRecordTypeDeregistering).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->ImmedAnswer && rr->resrec.RecordType == kDNSRecordTypeShared && rr->resrec.rrtype == kDNSType_PTR)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ResourceRecordIsValidAnswer(&m->DeviceInfo) && SameDomainLabel(rr->resrec.rdata->u.name.c, m->DeviceInfo.resrec.name->c))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!m->DeviceInfo.ImmedAnswer) m->DeviceInfo.ImmedAnswer = rr->ImmedAnswer;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else m->DeviceInfo.ImmedAnswer = mDNSInterfaceMark;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If there's a record which is supposed to be unique that we're going to send, then make sure that we give
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the whole RRSet as an atomic unit. That means that if we have any other records with the same name/type/class
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then we need to mark them for sending too. Otherwise, if we set the kDNSClass_UniqueRRSet bit on a
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // record, then other RRSet members that have not been sent recently will get flushed out of client caches.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // -- If a record is marked to be sent on a certain interface, make sure the whole set is marked to be sent on that interface
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // -- If any record is marked to be sent on all interfaces, make sure the whole set is marked to be sent on all interfaces
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->ImmedAnswer) // If we're sending this as answer, see that its whole RRSet is similarly marked
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome r2->ImmedAnswer != rr->ImmedAnswer && SameResourceRecordSignature(r2, rr))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome r2->ImmedAnswer = !r2->ImmedAnswer ? rr->ImmedAnswer : mDNSInterfaceMark;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (rr->ImmedAdditional) // If we're sending this as additional, see that its whole RRSet is similarly marked
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (r2->ImmedAdditional != rr->ImmedAdditional && SameResourceRecordSignature(r2, rr))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Now set SendRNow state appropriately
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->ImmedAnswer == mDNSInterfaceMark) // Sending this record on all appropriate interfaces
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->SendRNow = !intf ? mDNSNULL : (rr->resrec.InterfaceID) ? rr->resrec.InterfaceID : intf->InterfaceID;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->ImmedAdditional = mDNSNULL; // No need to send as additional if sending as answer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we're announcing this record, and it's at least half-way to its ordained time, then consider this announcement done
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (TimeToAnnounceThisRecord(rr, m->timenow + rr->ThisAPInterval/2))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType != kDNSRecordTypeDeregistering)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("Announcing %##s (%s) %d", rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype), rr->AnnounceCount);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (rr->ImmedAnswer) // Else, just respond to a single query on single interface:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->SendRNow = rr->ImmedAnswer; // Just respond on that interface
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->ImmedAdditional = mDNSNULL; // No need to send as additional too
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome //if (rr->SendRNow) LogMsg("%-15.4a %s", &rr->v4Requester, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *** 2. Loop through interface list, sending records as appropriate
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome int OwnerRecordSpace = (m->AnnounceOwner && intf->MAC.l[0]) ? DNSOpt_Header_Space + DNSOpt_Owner_Space(&m->PrimaryMAC, &intf->MAC) : 0;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome int TraceRecordSpace = (mDNS_McastTracingEnabled && MDNS_TRACER) ? DNSOpt_Header_Space + DNSOpt_TraceData_Space : 0;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome InitializeDNSMessage(&m->omsg.h, zeroID, ResponseFlags);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // First Pass. Look for:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1. Deregistering records that need to send their goodbye packet
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2. Updated records that need to retract their old data
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 3. Answers and announcements we need to send
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Skip this interface if the record InterfaceID is *Any and the record is not
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // appropriate for the interface type.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ((rr->resrec.InterfaceID == mDNSInterface_Any) && !mDNSPlatformValidRecordForInterface(rr, intf)))
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // LogInfo("SendResponses: Not sending %s, on %s", ARDisplayString(m, rr), InterfaceNameForID(m, rr->SendRNow));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (rr->resrec.RecordType != kDNSRecordTypeDeregistering && !ShouldSendGoodbyesBeforeSleep(m, intf, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // See if we should send a courtesy "goodbye" for the old data before we replace it.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ResourceRecordIsValidAnswer(rr) && rr->resrec.RecordType == kDNSRecordTypeShared && rr->RequireGoodbye)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome newptr = PutRR_OS_TTL(responseptr, &m->omsg.h.numAnswers, &rr->resrec, 0);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (newptr) { responseptr = newptr; numDereg++; rr->RequireGoodbye = mDNSfalse; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else continue; // If this packet is already too full to hold the goodbye for this record, skip it for now and we'll retry later
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SetNewRData(&rr->resrec, rr->NewRData, rr->newrdlength);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Adjust OwnerRecordSpace/TraceRecordSpace which is used by PutRR_OS_TTL below so that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we have space to put in the NSEC3 record in the authority section.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rrclass |= kDNSClass_UniqueRRSet; // Temporarily set the cache flush bit so PutResourceRecord will set it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome newptr = PutRR_OS_TTL(responseptr, &m->omsg.h.numAnswers, &rr->resrec, active ? rr->resrec.rroriginalttl : 0);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rrclass &= ~kDNSClass_UniqueRRSet; // Make sure to clear cache flush bit back to normal state
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType == kDNSRecordTypeDeregistering) numDereg++;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (rr->LastAPTime == m->timenow) numAnnounce++;else numAnswer++;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SetNewRData(&rr->resrec, OldRData, oldrdlength);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // The first time through (pktcount==0), if this record is verified unique
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (i.e. typically A, AAAA, SRV, TXT and reverse-mapping PTR), set the flag to add an NSEC too.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!pktcount && active && (rr->resrec.RecordType & kDNSRecordTypeActiveUniqueMask) && !rr->SendNSECNow)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (newptr) // If succeeded in sending, advance to next interface
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("SendResponses: Marking %s, OwnerRecordSpace %d, TraceRecordSpace %d, limit %p", ARDisplayString(m, rr), OwnerRecordSpace,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome TraceRecordSpace, m->omsg.data + AllowedRRSpace(&m->omsg) - OwnerRecordSpace - TraceRecordSpace);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.AnonInfo->SendNow = intf->InterfaceID;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If sending on all interfaces, go to next interface; else we're finished now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->ImmedAnswer == mDNSInterfaceMark && rr->resrec.InterfaceID == mDNSInterface_Any)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Get the reserved space back
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.AnonInfo && rr->resrec.AnonInfo->SendNow == intf->InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ResourceRecord *nsec3RR = rr->resrec.AnonInfo->nsec3RR;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome newptr = PutRR_OS_TTL(newptr, &m->omsg.h.numAuthorities, nsec3RR, nsec3RR->rroriginalttl);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("SendResponses: Added NSEC3 %s, OwnerRecordSpace %d, TraceRecordSpace %d, limit %p", ARDisplayString(m, rr), OwnerRecordSpace,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome TraceRecordSpace, m->omsg.data + AllowedRRSpace(&m->omsg) - OwnerRecordSpace - TraceRecordSpace);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("SendResponses: Cannot add NSEC3 %s, OwnerRecordSpace %d, TraceRecordSpace %d, limit %p", ARDisplayString(m, rr), OwnerRecordSpace,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome TraceRecordSpace, m->omsg.data + AllowedRRSpace(&m->omsg) - OwnerRecordSpace - TraceRecordSpace);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Second Pass. Add additional records, if there's space.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we have at least one answer already in the packet, then plan to add additionals too
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSBool SendAdditional = (m->omsg.h.numAnswers > 0);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we're not planning to send any additionals, but this record is a unique one, then
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // make sure we haven't already sent any other members of its RRSet -- if we have, then they
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // will have had the cache flush bit set, so now we need to finish the job and send the rest.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!SendAdditional && (rr->resrec.RecordType & kDNSRecordTypeUniqueMask))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SameResourceRecordSignature(a, rr)) { SendAdditional = mDNStrue; break; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!SendAdditional) // If we don't want to send this after all,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->ImmedAdditional = mDNSNULL; // then cancel its ImmedAdditional field
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (newptr) // Else, try to add it if we can
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // The first time through (pktcount==0), if this record is verified unique
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (i.e. typically A, AAAA, SRV, TXT and reverse-mapping PTR), set the flag to add an NSEC too.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!pktcount && (rr->resrec.RecordType & kDNSRecordTypeActiveUniqueMask) && !rr->SendNSECNow)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rrclass |= kDNSClass_UniqueRRSet; // Temporarily set the cache flush bit so PutResourceRecord will set it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome newptr = PutRR_OS(newptr, &m->omsg.h.numAdditionals, &rr->resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rrclass &= ~kDNSClass_UniqueRRSet; // Make sure to clear cache flush bit back to normal state
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we successfully put this additional record in the packet, we record LastMCTime & LastMCInterface.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This matters particularly in the case where we have more than one IPv6 (or IPv4) address, because otherwise,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // when we see our own multicast with the cache flush bit set, if we haven't set LastMCTime, then we'll get
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // all concerned and re-announce our record again to make sure it doesn't get flushed from peer caches.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Third Pass. Add NSEC records, if there's space.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When we're generating an NSEC record in response to a specify query for that type
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (recognized by rr->SendNSECNow == intf->InterfaceID) we should really put the NSEC in the Answer Section,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // not Additional Section, but for now it's easier to handle both cases in this Additional Section loop here.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->SendNSECNow == mDNSInterfaceMark || rr->SendNSECNow == intf->InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetupResourceRecord(&nsec, mDNSNULL, mDNSInterface_Any, kDNSType_NSEC, rr->resrec.rroriginalttl, kDNSRecordTypeUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName(&nsec.namestorage, rr->resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We have a nxt name followed by window number, window length and a window bitmap
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome nsec.resrec.rdlength = len + 2 + NSEC_MCAST_WINDOW_SIZE;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (nsec.resrec.rdlength <= StandardAuthRDSize)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformMemZero(ptr, nsec.resrec.rdlength);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName((domainname *)ptr, rr->resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *ptr++ = NSEC_MCAST_WINDOW_SIZE; // window length
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ResourceRecordIsValidAnswer(r2) && SameResourceRecordNameClassInterface(r2, rr))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (r2->resrec.rrtype >= kDNSQType_ANY) { LogMsg("SendResponses: Can't create NSEC for record %s", ARDisplayString(m, r2)); break; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else ptr[r2->resrec.rrtype >> 3] |= 128 >> (r2->resrec.rrtype & 7);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!r2) // If we successfully built our NSEC record, add it to the packet now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome newptr = PutRR_OS(responseptr, &m->omsg.h.numAdditionals, &nsec.resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else LogMsg("SendResponses: not enough space (%d) in authrecord for nsec", nsec.resrec.rdlength);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we successfully put the NSEC record, clear the SendNSECNow flag
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we consider this NSEC optional, then we unconditionally clear the SendNSECNow flag, even if we fail to put this additional record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (newptr || rr->SendNSECNow == mDNSInterfaceMark)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Run through remainder of list clearing SendNSECNow flag for all other records which would generate the same NSEC
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SameResourceRecordNameClassInterface(r2, rr))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (r2->SendNSECNow == mDNSInterfaceMark || r2->SendNSECNow == intf->InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->omsg.h.numAnswers || m->omsg.h.numAdditionals)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we have data to send, add OWNER/TRACER/OWNER+TRACER option if necessary, then send packet
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetupResourceRecord(&opt, mDNSNULL, mDNSInterface_Any, kDNSType_OPT, kStandardTTL, kDNSRecordTypeKnownUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome opt.resrec.rdlength += sizeof(rdataOPT); // Two options in this OPT record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SetupOwnerOpt(m, intf, &opt.resrec.rdata->u.opt[0]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SetupTracerOpt(m, &opt.resrec.rdata->u.opt[1]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SetupOwnerOpt(m, intf, &opt.resrec.rdata->u.opt[0]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SetupTracerOpt(m, &opt.resrec.rdata->u.opt[0]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome newptr = PutResourceRecord(&m->omsg, responseptr, &m->omsg.h.numAdditionals, &opt.resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("SendResponses put %s %s: %s %s", OwnerRecordSpace ? "OWNER" : "", TraceRecordSpace ? "TRACER" : "", intf->ifname, ARDisplayString(m, &opt));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (m->omsg.h.numAnswers + m->omsg.h.numAuthorities + m->omsg.h.numAdditionals == 1)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("SendResponses: No space in packet for %s %s OPT record (%d/%d/%d/%d) %s", OwnerRecordSpace ? "OWNER" : "", TraceRecordSpace ? "TRACER" : "",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->omsg.h.numQuestions, m->omsg.h.numAnswers, m->omsg.h.numAuthorities, m->omsg.h.numAdditionals, ARDisplayString(m, &opt));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("SendResponses: How did we fail to have space for %s %s OPT record (%d/%d/%d/%d) %s", OwnerRecordSpace ? "OWNER" : "", TraceRecordSpace ? "TRACER" : "",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->omsg.h.numQuestions, m->omsg.h.numAnswers, m->omsg.h.numAuthorities, m->omsg.h.numAdditionals, ARDisplayString(m, &opt));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("SendResponses: Sending %d Deregistration%s, %d Announcement%s, %d Answer%s, %d Additional%s on %p",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->omsg.h.numAdditionals, m->omsg.h.numAdditionals == 1 ? "" : "s", intf->InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (intf->IPv4Available) mDNSSendDNSMessage(m, &m->omsg, responseptr, intf->InterfaceID, mDNSNULL, &AllDNSLinkGroup_v4, MulticastDNSPort, mDNSNULL, mDNSNULL, mDNSfalse);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (intf->IPv6Available) mDNSSendDNSMessage(m, &m->omsg, responseptr, intf->InterfaceID, mDNSNULL, &AllDNSLinkGroup_v6, MulticastDNSPort, mDNSNULL, mDNSNULL, mDNSfalse);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!m->SuppressSending) m->SuppressSending = NonZeroTime(m->timenow + (mDNSPlatformOneSecond+9)/10);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (++pktcount >= 1000) { LogMsg("SendResponses exceeded loop limit %d: giving up", pktcount); break; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // There might be more things to send on this interface, so go around one more time and try again.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else // Nothing more to send on this interface; go to next
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const NetworkInterfaceInfo *next = GetFirstActiveInterface(intf->next);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const char *const msg = next ? "SendResponses: Nothing more on %p; moving to %p" : "SendResponses: Nothing more on %p";
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome pktcount = 0; // When we move to a new interface, reset packet count back to zero -- NSEC generation logic uses it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *** 3. Cleanup: Now that everything is sent, call client callback functions, and reset state variables
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("SendResponses ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->ARType != AuthRecordLocalOnly && rr->ARType != AuthRecordP2P)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("SendResponses: No active interface %d to send: %d %02X %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (uint32_t)rr->SendRNow, (uint32_t)rr->resrec.InterfaceID, rr->resrec.RecordType, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->ImmedAnswer || rr->resrec.RecordType == kDNSRecordTypeDeregistering)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->NewRData) CompleteRDataUpdate(m, rr); // Update our rdata, clear the NewRData pointer, and return memory to the client
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType == kDNSRecordTypeDeregistering && rr->AnnounceCount == 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For Unicast, when we get the response from the server, we will call CompleteDeregistration
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!AuthRecord_uDNS(rr)) CompleteDeregistration(m, rr); // Don't touch rr after this
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome verbosedebugf("SendResponses: Next in %ld ticks", m->NextScheduledResponse - m->timenow);
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Calling CheckCacheExpiration() is an expensive operation because it has to look at the entire cache,
4b22b9337f359bfd063322244f5336cc7c6ffcfars// so we want to be lazy about how frequently we do it.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// 1. If a cache record is currently referenced by *no* active questions,
4b22b9337f359bfd063322244f5336cc7c6ffcfars// then we don't mind expiring it up to a minute late (who will know?)
4b22b9337f359bfd063322244f5336cc7c6ffcfars// 2. Else, if a cache record is due for some of its final expiration queries,
4b22b9337f359bfd063322244f5336cc7c6ffcfars// we'll allow them to be late by up to 2% of the TTL
4b22b9337f359bfd063322244f5336cc7c6ffcfars// 3. Else, if a cache record has completed all its final expiration queries without success,
4b22b9337f359bfd063322244f5336cc7c6ffcfars// and is expiring, and had an original TTL more than ten seconds, we'll allow it to be one second late
4b22b9337f359bfd063322244f5336cc7c6ffcfars// 4. Else, it is expiring and had an original TTL of ten seconds or less (includes explicit goodbye packets),
4b22b9337f359bfd063322244f5336cc7c6ffcfars// so allow at most 1/10 second lateness
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// 5. For records with rroriginalttl set to zero, that means we really want to delete them immediately
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// (we have a new record with DelayDelivery set, waiting for the old record to go away before we can notify clients).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ((RR)->CRActiveQuestion == mDNSNULL ) ? (60 * mDNSPlatformOneSecond) : \
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ((RR)->UnansweredQueries < MaxUnansweredQueries) ? (TicksTTL(rr)/50) : \
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ((RR)->resrec.rroriginalttl > 10 ) ? (mDNSPlatformOneSecond) : \
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ((RR)->resrec.rroriginalttl > 0 ) ? (mDNSPlatformOneSecond/10) : 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#define NextCacheCheckEvent(RR) ((RR)->NextRequiredQuery + CacheCheckGracePeriod(RR))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void ScheduleNextCacheCheckTime(mDNS *const m, const mDNSu32 slot, const mDNSs32 event)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Note: MUST call SetNextCacheCheckTimeForRecord any time we change:
4b22b9337f359bfd063322244f5336cc7c6ffcfars// rr->TimeRcvd
4b22b9337f359bfd063322244f5336cc7c6ffcfars// rr->resrec.rroriginalttl
4b22b9337f359bfd063322244f5336cc7c6ffcfars// rr->UnansweredQueries
4b22b9337f359bfd063322244f5336cc7c6ffcfars// rr->CRActiveQuestion
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void SetNextCacheCheckTimeForRecord(mDNS *const m, CacheRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we have an active question, then see if we want to schedule a refresher query for this record.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Usually we expect to do four queries, at 80-82%, 85-87%, 90-92% and then 95-97% of the TTL.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->CRActiveQuestion && rr->UnansweredQueries < MaxUnansweredQueries)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->NextRequiredQuery -= TicksTTL(rr)/20 * (MaxUnansweredQueries - rr->UnansweredQueries);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->NextRequiredQuery += mDNSRandom((mDNSu32)TicksTTL(rr)/50);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome verbosedebugf("SetNextCacheCheckTimeForRecord: NextRequiredQuery in %ld sec CacheCheckGracePeriod %d ticks for %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (rr->NextRequiredQuery - m->timenow) / mDNSPlatformOneSecond, CacheCheckGracePeriod(rr), CRDisplayString(m,rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ScheduleNextCacheCheckTime(m, HashSlot(rr->resrec.name), NextCacheCheckEvent(rr));
4b22b9337f359bfd063322244f5336cc7c6ffcfars#define kMinimumReconfirmTime ((mDNSu32)mDNSPlatformOneSecond * 5)
4b22b9337f359bfd063322244f5336cc7c6ffcfars#define kDefaultReconfirmTimeForWake ((mDNSu32)mDNSPlatformOneSecond * 5)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#define kDefaultReconfirmTimeForNoAnswer ((mDNSu32)mDNSPlatformOneSecond * 5)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#define kDefaultReconfirmTimeForFlappingInterface ((mDNSu32)mDNSPlatformOneSecond * 5)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport mStatus mDNS_Reconfirm_internal(mDNS *const m, CacheRecord *const rr, mDNSu32 interval)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (interval > 0x10000000) // Make sure interval doesn't overflow when we multiply by four below
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the expected expiration time for this record is more than interval+33%, then accelerate its expiration
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (RRExpireTime(rr) - m->timenow > (mDNSs32)((interval * 4) / 3))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Add a 33% random amount to the interval, to avoid synchronization between multiple hosts
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For all the reconfirmations in a given batch, we want to use the same random value
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // so that the reconfirmation questions can be grouped into a single query packet
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!m->RandomReconfirmDelay) m->RandomReconfirmDelay = 1 + mDNSRandom(0x3FFFFFFF);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome interval += m->RandomReconfirmDelay % ((interval/3) + 1);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->TimeRcvd = m->timenow - (mDNSs32)interval * 3;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rroriginalttl = (interval * 4 + mDNSPlatformOneSecond - 1) / mDNSPlatformOneSecond;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_Reconfirm_internal:%6ld ticks to go for %s %p",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome RRExpireTime(rr) - m->timenow, CRDisplayString(m, rr), rr->CRActiveQuestion);
4b22b9337f359bfd063322244f5336cc7c6ffcfars// BuildQuestion puts a question into a DNS Query packet and if successful, updates the value of queryptr.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// It also appends to the list of known answer records that need to be included,
4b22b9337f359bfd063322244f5336cc7c6ffcfars// and updates the forcast for the size of the known answer section.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas SoomemDNSlocal mDNSBool BuildQuestion(mDNS *const m, const NetworkInterfaceInfo *intf, DNSMessage *query, mDNSu8 **queryptr,
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome DNSQuestion *q, CacheRecord ***kalistptrptr, mDNSu32 *answerforecast)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome mDNSBool ucast = (q->LargeAnswers || q->RequestUnicast) && m->CanReceiveUnicastOn5353 && intf->SupportsUnicastMDNSResponse;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu16 ucbit = (mDNSu16)(ucast ? kDNSQClass_UnicastResponse : 0);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu8 *const limit = query->data + NormalMaxDNSMessageData;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu8 anoninfo_space = q->AnonInfo ? AnonInfoSpace(q->AnonInfo) : 0;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu8 *newptr = putQuestion(query, *queryptr, limit - *answerforecast - anoninfo_space, &q->qname, q->qtype, (mDNSu16)(q->qclass | ucbit));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("BuildQuestion: No more space in this packet for question %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu32 forecast = *answerforecast + anoninfo_space;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const CacheGroup *const cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheRecord **ka = *kalistptrptr; // Make a working copy of the pointer we're going to update
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next) // If we have a resource record in our cache,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.InterfaceID == q->SendQNow && // received on this interface
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome !(rr->resrec.RecordType & kDNSRecordTypeUniqueMask) && // which is a shared (i.e. not unique) record type
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->NextInKAList == mDNSNULL && ka != &rr->NextInKAList && // which is not already in the known answer list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rdlength <= SmallRecordLimit && // which is small enough to sensibly fit in the packet
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SameNameRecordAnswersQuestion(&rr->resrec, q) && // which answers our question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->TimeRcvd + TicksTTL(rr)/2 - m->timenow > // and its half-way-to-expiry time is at least 1 second away
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformOneSecond) // (also ensures we never include goodbye records with TTL=1)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We don't want to include unique records in the Known Answer section. The Known Answer section
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // is intended to suppress floods of shared-record replies from many other devices on the network.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // That concept really does not apply to unique records, and indeed if we do send a query for
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // which we have a unique record already in our cache, then including that unique record as a
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Known Answer, so as to suppress the only answer we were expecting to get, makes little sense.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *ka = rr; // Link this record into our known answer chain
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We forecast: compressed name (2) type (2) class (2) TTL (4) rdlength (2) rdata (n)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we're trying to put more than one question in this packet, and it doesn't fit
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then undo that last question and try again next time
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (query->h.numQuestions > 1 && newptr + forecast >= limit)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("BuildQuestion: Retracting question %##s (%s) new forecast total %d, total questions %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->qname.c, DNSTypeName(q->qtype), newptr + forecast - query->data, query->h.numQuestions);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ka = *kalistptrptr; // Go back to where we started and retract these answer records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (*ka) { CacheRecord *c = *ka; *ka = mDNSNULL; ka = &c->NextInKAList; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome return(mDNSfalse); // Return false, so we'll try again in the next packet
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Success! Update our state pointers, increment UnansweredQueries as appropriate, and return
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *queryptr = newptr; // Update the packet pointer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *answerforecast = forecast; // Update the forecast
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *kalistptrptr = ka; // Update the known answer list pointer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ucast) q->ExpectUnicastResp = NonZeroTime(m->timenow);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next) // For every resource record in our cache,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.InterfaceID == q->SendQNow && // received on this interface
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->NextInKAList == mDNSNULL && ka != &rr->NextInKAList && // which is not in the known answer list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SameNameRecordAnswersQuestion(&rr->resrec, q)) // which answers our question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->UnansweredQueries++; // indicate that we're expecting a response
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// When we have a query looking for a specified name, but there appear to be no answers with
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// that name, ReconfirmAntecedents() is called with depth=0 to start the reconfirmation process
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// for any records in our cache that reference the given name (e.g. PTR and SRV records).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// For any such cache record we find, we also recursively call ReconfirmAntecedents() for *its* name.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// We increment depth each time we recurse, to guard against possible infinite loops, with a limit of 5.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// A typical reconfirmation scenario might go like this:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Depth 0: Name "myhost.local" has no address records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Depth 1: SRV "My Service._example._tcp.local." refers to "myhost.local"; may be stale
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Depth 2: PTR "_example._tcp.local." refers to "My Service"; may be stale
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Depth 3: PTR "_services._dns-sd._udp.local." refers to "_example._tcp.local."; may be stale
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Currently depths 4 and 5 are not expected to occur; if we did get to depth 5 we'd reconfim any records we
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// found referring to the given name, but not recursively descend any further reconfirm *their* antecedents.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void ReconfirmAntecedents(mDNS *const m, const domainname *const name, const mDNSu32 namehash, const int depth)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("ReconfirmAntecedents (depth=%d) for %##s", depth, name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome domainname *crtarget = GetRRDomainNameTarget(&cr->resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (crtarget && cr->resrec.rdatahash == namehash && SameDomainName(crtarget, name))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ReconfirmAntecedents: Reconfirming (depth=%d) %s", depth, CRDisplayString(m, cr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Reconfirm_internal(m, cr, kDefaultReconfirmTimeForNoAnswer);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ReconfirmAntecedents(m, cr->resrec.name, cr->resrec.namehash, depth+1);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// If we get no answer for a AAAA query, then before doing an automatic implicit ReconfirmAntecedents
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// we check if we have an address record for the same name. If we do have an IPv4 address for a given
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// name but not an IPv6 address, that's okay (it just means the device doesn't do IPv6) so the failure
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// to get a AAAA response is not grounds to doubt the PTR/SRV chain that lead us to that name.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal const CacheRecord *CacheHasAddressTypeForName(mDNS *const m, const domainname *const name, const mDNSu32 namehash)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheGroup *const cg = CacheGroupForName(m, HashSlot(name), namehash, name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const CacheRecord *cr = cg ? cg->members : mDNSNULL;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (cr && !RRTypeIsAddressType(cr->resrec.rrtype)) cr=cr->next;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal const CacheRecord *FindSPSInCache1(mDNS *const m, const DNSQuestion *const q, const CacheRecord *const c0, const CacheRecord *const c1)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheGroup *const cg = CacheGroupForName(m, HashSlot(&q->qname), q->qnamehash, &q->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (cr = cg ? cg->members : mDNSNULL; cr; cr=cr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (cr->resrec.rrtype == kDNSType_PTR && cr->resrec.rdlength >= 6) // If record is PTR type, with long enough name,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (cr != c0 && cr != c1) // that's not one we've seen before,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SameNameRecordAnswersQuestion(&cr->resrec, q)) // and answers our browse query,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!IdenticalSameNameRecord(&cr->resrec, &m->SPSRecords.RR_PTR.resrec)) // and is not our own advertised service...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu32 metric = SPSMetric(cr->resrec.rdata->u.name.c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (bestmetric > metric) { bestmetric = metric; bestcr = cr; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#else // SPC_DISABLED
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // SPC_DISABLED
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas SoomemDNSlocal void CheckAndSwapSPS(const CacheRecord **sps1, const CacheRecord **sps2)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome metric1 = SPSMetric((*sps1)->resrec.rdata->u.name.c);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome metric2 = SPSMetric((*sps2)->resrec.rdata->u.name.c);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (!SPSFeatures((*sps1)->resrec.rdata->u.name.c) && SPSFeatures((*sps2)->resrec.rdata->u.name.c) && (metric2 >= metric1))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void ReorderSPSByFeature(const CacheRecord *sps[3])
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Finds the three best Sleep Proxies we currently have in our cache
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void FindSPSInCache(mDNS *const m, const DNSQuestion *const q, const CacheRecord *sps[3])
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome sps[0] = FindSPSInCache1(m, q, mDNSNULL, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome sps[1] = !sps[0] ? mDNSNULL : FindSPSInCache1(m, q, sps[0], mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome sps[2] = !sps[1] ? mDNSNULL : FindSPSInCache1(m, q, sps[0], sps[1]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // SPS is already sorted by metric. We want to move the entries to the beginning of the array
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // only if they have equally good metric and support features.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Only DupSuppressInfos newer than the specified 'time' are allowed to remain active
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void ExpireDupSuppressInfo(DupSuppressInfo ds[DupSuppressInfoSize], mDNSs32 time)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<DupSuppressInfoSize; i++) if (ds[i].Time - time < 0) ds[i].InterfaceID = mDNSNULL;
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void ExpireDupSuppressInfoOnInterface(DupSuppressInfo ds[DupSuppressInfoSize], mDNSs32 time, mDNSInterfaceID InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<DupSuppressInfoSize; i++) if (ds[i].InterfaceID == InterfaceID && ds[i].Time - time < 0) ds[i].InterfaceID = mDNSNULL;
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal mDNSBool SuppressOnThisInterface(const DupSuppressInfo ds[DupSuppressInfoSize], const NetworkInterfaceInfo * const intf)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSBool v4 = !intf->IPv4Available; // If this interface doesn't do v4, we don't need to find a v4 duplicate of this query
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSBool v6 = !intf->IPv6Available; // If this interface doesn't do v6, we don't need to find a v6 duplicate of this query
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<DupSuppressInfoSize; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ds[i].Type == mDNSAddrType_IPv4) v4 = mDNStrue;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (ds[i].Type == mDNSAddrType_IPv6) v6 = mDNStrue;
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas SoomemDNSlocal void RecordDupSuppressInfo(DupSuppressInfo ds[DupSuppressInfoSize], mDNSs32 Time, mDNSInterfaceID InterfaceID, mDNSs32 Type)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // See if we have this one in our list somewhere already
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<DupSuppressInfoSize; i++) if (ds[i].InterfaceID == InterfaceID && ds[i].Type == Type) break;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If not, find a slot we can re-use
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (j=1; j<DupSuppressInfoSize && ds[i].InterfaceID; j++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!ds[j].InterfaceID || ds[j].Time - ds[i].Time < 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Record the info about this query we saw
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNSSendWakeOnResolve(mDNS *const m, DNSQuestion *q)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We can't send magic packets without knowing which interface to send it on.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (InterfaceID == mDNSInterface_Any || InterfaceID == mDNSInterface_LocalOnly || InterfaceID == mDNSInterface_P2P)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNSSendWakeOnResolve: ERROR!! Invalid InterfaceID %p for question %##s", InterfaceID, q->qname.c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Split MAC@IPAddress and pass them separately
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (d->c[i] == '@')
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome char EthAddr[18]; // ethernet adddress : 12 bytes + 5 ":" + 1 NULL byte
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome char IPAddr[47]; // Max IP address len: 46 bytes (IPv6) + 1 NULL byte
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNSSendWakeOnResolve: ERROR!! Malformed Ethernet address %##s, cnt %d", q->qname.c, cnt);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNSSendWakeOnResolve: ERROR!! Malformed Ethernet address %##s, length %d", q->qname.c, i - 1);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNSSendWakeOnResolve: ERROR!! Malformed IP address %##s, length %d", q->qname.c, len - i);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformMemCopy(IPAddr, &d->c[i + 1], len - i);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformSendWakeupPacket(m, InterfaceID, EthAddr, IPAddr, InitialWakeOnResolveCount - q->WakeOnResolveCount);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (d->c[i] == ':')
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNSSendWakeOnResolve: ERROR!! Malformed WakeOnResolve name %##s", q->qname.c);
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal mDNSBool AccelerateThisQuery(mDNS *const m, DNSQuestion *q)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If more than 90% of the way to the query time, we should unconditionally accelerate it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (TimeToSendThisQuestion(q, m->timenow + q->ThisQInterval/10))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If half-way to next scheduled query time, only accelerate if it will add less than 512 bytes to the packet
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (TimeToSendThisQuestion(q, m->timenow + q->ThisQInterval/2))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We forecast: qname (n) type (2) class (2)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu32 forecast = (mDNSu32)DomainNameLength(&q->qname) + 4;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const CacheGroup *const cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next) // If we have a resource record in our cache,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.rdlength <= SmallRecordLimit && // which is small enough to sensibly fit in the packet
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SameNameRecordAnswersQuestion(&rr->resrec, q) && // which answers our question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->TimeRcvd + TicksTTL(rr)/2 - m->timenow >= 0 && // and it is less than half-way to expiry
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->NextRequiredQuery - (m->timenow + q->ThisQInterval) > 0) // and we'll ask at least once again before NextRequiredQuery
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We forecast: compressed name (2) type (2) class (2) TTL (4) rdlength (2) rdata (n)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (forecast >= 512) return(mDNSfalse); // If this would add 512 bytes or more to the packet, don't accelerate
4b22b9337f359bfd063322244f5336cc7c6ffcfars// How Standard Queries are generated:
4b22b9337f359bfd063322244f5336cc7c6ffcfars// 1. The Question Section contains the question
4b22b9337f359bfd063322244f5336cc7c6ffcfars// 2. The Additional Section contains answers we already know, to suppress duplicate responses
4b22b9337f359bfd063322244f5336cc7c6ffcfars// How Probe Queries are generated:
4b22b9337f359bfd063322244f5336cc7c6ffcfars// 1. The Question Section contains queries for the name we intend to use, with QType=ANY because
4b22b9337f359bfd063322244f5336cc7c6ffcfars// if some other host is already using *any* records with this name, we want to know about it.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// 2. The Authority Section contains the proposed values we intend to use for one or more
4b22b9337f359bfd063322244f5336cc7c6ffcfars// of our records with that name (analogous to the Update section of DNS Update packets)
4b22b9337f359bfd063322244f5336cc7c6ffcfars// because if some other host is probing at the same time, we each want to know what the other is
4b22b9337f359bfd063322244f5336cc7c6ffcfars// planning, in order to apply the tie-breaking rule to see who gets to use the name and who doesn't.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For explanation of maxExistingQuestionInterval logic, see comments for maxExistingAnnounceInterval
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const NetworkInterfaceInfo *intf = GetFirstActiveInterface(m->HostInterfaces);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1. If time for a query, work out what we need to do
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We're expecting to send a query anyway, so see if any expiring cache records are close enough
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to their NextRequiredQuery to be worth batching them together with this one
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (cr->CRActiveQuestion && cr->UnansweredQueries < MaxUnansweredQueries)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->timenow + TicksTTL(cr)/50 - cr->NextRequiredQuery >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("Sending %d%% cache expiration query for %s", 80 + 5 * cr->UnansweredQueries, CRDisplayString(m, cr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ExpireDupSuppressInfoOnInterface(q->DupSuppress, m->timenow - TicksTTL(cr)/20, cr->resrec.InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For uDNS queries (TargetQID non-zero) we adjust LastQTime,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and bump UnansweredQueries so that we don't spin trying to send the same cache expiration query repeatedly
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->SendQNow = mDNSInterfaceMark; // If targeted query, mark it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (q->SendQNow != cr->resrec.InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Indicate that this question was marked for sending
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to update an existing cached answer record.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // The browse throttling logic below uses this to determine
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // if the query should be sent.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Scan our list of questions to see which:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *WideArea* queries need to be sent
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *unicast* queries need to be sent
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *multicast* queries we're definitely going to send
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("SendQueries ERROR m->CurrentQuestion already set: %##s (%s)", m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (m->CurrentQuestion && m->CurrentQuestion != m->NewQuestions)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q->Target.type && (q->SendQNow || TimeToSendThisQuestion(q, m->timenow)))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu8 *const limit = m->omsg.data + sizeof(m->omsg.data);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we fail to get a new on-demand socket (should only happen cases of the most extreme resource exhaustion), we'll try again next time
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!q->LocalSocket) q->LocalSocket = mDNSPlatformUDPSocket(m, zeroIPPort);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome InitializeDNSMessage(&m->omsg.h, q->TargetQID, QueryFlags);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome qptr = putQuestion(&m->omsg, qptr, limit, &q->qname, q->qtype, q->qclass);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSSendDNSMessage(m, &m->omsg, qptr, mDNSInterface_Any, q->LocalSocket, &q->Target, q->TargetPort, mDNSNULL, mDNSNULL, q->UseBackgroundTrafficClass);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->ExpectUnicastResp = NonZeroTime(m->timenow);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (mDNSOpaque16IsZero(q->TargetQID) && !q->Target.type && TimeToSendThisQuestion(q, m->timenow))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome //LogInfo("Time to send %##s (%s) %d", q->qname.c, DNSTypeName(q->qtype), m->timenow - NextQSendTime(q));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->SendQNow = mDNSInterfaceMark; // Mark this question for sending on all interfaces
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (maxExistingQuestionInterval < q->ThisQInterval)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome maxExistingQuestionInterval = q->ThisQInterval;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If m->CurrentQuestion wasn't modified out from under us, advance it now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We can't do this at the start of the loop because uDNS_CheckCurrentQuestion() depends on having
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // m->CurrentQuestion point to the right question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q == m->CurrentQuestion) m->CurrentQuestion = m->CurrentQuestion->next;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("SendQueries question loop 1: Skipping NewQuestion %##s (%s)", m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Scan our list of questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (a) to see if there are any more that are worth accelerating, and
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (b) to update the state variables for *all* the questions we're going to send
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: Don't set NextScheduledQuery until here, because uDNS_CheckCurrentQuestion in the loop above can add new questions to the list,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // which causes NextScheduledQuery to get (incorrectly) set to m->timenow. Setting it here is the right place, because the very
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // next thing we do is scan the list and call SetNextQueryTime() for every question we find, so we know we end up with the right value.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NextScheduledQuery = m->timenow + 0x78000000;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (q = m->Questions; q && q != m->NewQuestions; q=q->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome && (q->SendQNow || (!q->Target.type && ActiveQuestion(q) && q->ThisQInterval <= maxExistingQuestionInterval && AccelerateThisQuery(m,q))))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If at least halfway to next query time, advance to next interval
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If less than halfway to next query time, then
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // treat this as logically a repeat of the last transmission, without advancing the interval
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->timenow - (q->LastQTime + (q->ThisQInterval/2)) >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we have reached the answer threshold for this question,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // don't send it again until MaxQuestionInterval unless:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // one of its cached answers needs to be refreshed,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // or it's the initial query for a kDNSServiceFlagsThresholdFinder mode browse.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome && !((q->flags & kDNSServiceFlagsThresholdFinder) && (q->ThisQInterval == InitialQuestionInterval)))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("SendQueries: (%s) %##s reached threshold of %d answers",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome DNSTypeName(q->qtype), q->qname.c, q->BrowseThreshold);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Mark this question for sending on all interfaces
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("SendQueries: %##s (%s) next interval %d seconds RequestUnicast = %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->qname.c, DNSTypeName(q->qtype), q->ThisQInterval / InitialQuestionInterval, q->RequestUnicast);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q->ThisQInterval >= QuestionIntervalThreshold)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (q->CurrentAnswers == 0 && q->ThisQInterval == InitialQuestionInterval * QuestionIntervalStep3 && !q->RequestUnicast &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome !(RRTypeIsAddressType(q->qtype) && CacheHasAddressTypeForName(m, &q->qname, q->qnamehash)))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Generally don't need to log this.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // It's not especially noteworthy if a query finds no results -- this usually happens for domain
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // enumeration queries in the LL subdomain (e.g. "db._dns-sd._udp.0.0.254.169.in-addr.arpa")
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and when there simply happen to be no instances of the service the client is looking
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // for (e.g. iTunes is set to look for RAOP devices, and the current network has none).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("SendQueries: Zero current answers for %##s (%s); will reconfirm antecedents",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Sending third query, and no answers yet; time to begin doubting the source
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ReconfirmAntecedents(m, &q->qname, q->qnamehash, 0);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Mark for sending. (If no active interfaces, then don't even try.)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->SendOnAll = (q->SendQNow == mDNSInterfaceMark);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->SendQNow = !intf ? mDNSNULL : (q->InterfaceID) ? q->InterfaceID : intf->InterfaceID;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we recorded a duplicate suppression for this question less than half an interval ago,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then we consider it recent enough that we don't need to do an identical query ourselves.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ExpireDupSuppressInfo(q->DupSuppress, m->timenow - q->ThisQInterval/2);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For all questions (not just the ones we're sending) check what the next scheduled event will be
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We don't need to consider NewQuestions here because for those we'll set m->NextScheduledQuery in AnswerNewQuestion
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2. Scan our authoritative RR list to see what probes we might need to send
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NextScheduledProbe = m->timenow + 0x78000000;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("SendQueries ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!AuthRecord_uDNS(ar) && ar->resrec.RecordType == kDNSRecordTypeUnique) // For all records that are still probing...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1. If it's not reached its probe time, just make sure we update m->NextScheduledProbe correctly
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->timenow - (ar->LastAPTime + ar->ThisAPInterval) < 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2. else, if it has reached its probe time, mark it for sending and then update m->NextScheduledProbe correctly
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ar->AddressProxy.type == mDNSAddrType_IPv4)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // There's a problem here. If a host is waking up, and we probe to see if it responds, then
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // it will see those ARP probes as signalling intent to use the address, so it picks a different one.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // A more benign way to find out if a host is responding to ARPs might be send a standard ARP *request*
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (using our sender IP address) instead of an ARP *probe* (using all-zero sender IP address).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // A similar concern may apply to the NDP Probe too. -- SC
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("SendQueries ARP Probe %d %s %s", ar->ProbeCount, InterfaceNameForID(m, ar->resrec.InterfaceID), ARDisplayString(m,ar));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SendARP(m, 1, ar, &zerov4Addr, &zeroEthAddr, &ar->AddressProxy.ip.v4, &ar->WakeUp.IMAC);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (ar->AddressProxy.type == mDNSAddrType_IPv6)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("SendQueries NDP Probe %d %s %s", ar->ProbeCount, InterfaceNameForID(m, ar->resrec.InterfaceID), ARDisplayString(m,ar));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // IPv6 source = zero
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // No target hardware address
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // IPv6 target address is address we're probing
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Ethernet destination address is Ethernet interface address of the Sleep Proxy client we're probing
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SendNDP(m, NDP_Sol, 0, ar, &zerov6Addr, mDNSNULL, &ar->AddressProxy.ip.v6, &ar->WakeUp.IMAC);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Mark for sending. (If no active interfaces, then don't even try.)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ar->SendRNow = (!intf || ar->WakeUp.HMAC.l[0]) ? mDNSNULL : ar->resrec.InterfaceID ? ar->resrec.InterfaceID : intf->InterfaceID;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When we have a late conflict that resets a record to probing state we use a special marker value greater
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // than DefaultProbeCountForTypeUnique. Here we detect that state and reset ar->ProbeCount back to the right value.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ar->ProbeCount > DefaultProbeCountForTypeUnique)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ar->ProbeCount = DefaultProbeCountForTypeUnique;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this is the last probe for this record, then see if we have any matching records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // on our duplicate list which should similarly have their ProbeCount cleared to zero...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (r2 = m->DuplicateRecords; r2; r2=r2->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (r2->resrec.RecordType == kDNSRecordTypeUnique && RecordIsLocalDuplicate(r2, ar))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // ... then acknowledge this record to the client.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We do this optimistically, just as we're about to send the third probe.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This helps clients that both advertise and browse, and want to filter themselves
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // from the browse results list, because it helps ensure that the registration
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // confirmation will be delivered 1/4 second *before* the browse "add" event.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // A potential downside is that we could deliver a registration confirmation and then find out
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // moments later that there's a name conflict, but applications have to be prepared to handle
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // late conflicts anyway (e.g. on connection of network cable, etc.), so this is nothing new.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!ar->Acknowledged) AcknowledgeRecord(m, ar);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // else, if it has now finished probing, move it to state Verified,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and update m->NextScheduledResponse so it will be announced
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!ar->Acknowledged) AcknowledgeRecord(m, ar); // Defensive, just in case it got missed somehow
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ar->resrec.RecordType = kDNSRecordTypeVerified;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ar->ThisAPInterval = DefaultAnnounceIntervalForTypeUnique;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ar->LastAPTime = m->timenow - DefaultAnnounceIntervalForTypeUnique;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ar->resrec.RecordType == kDNSRecordTypeUnique && ar->ProbeCount == 0 && !ar->Acknowledged)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 3. Now we know which queries and probes we're sending,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // go through our interface list sending the appropriate queries on each interface
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome int OwnerRecordSpace = (m->AnnounceOwner && intf->MAC.l[0]) ? DNSOpt_Header_Space + DNSOpt_Owner_Space(&m->PrimaryMAC, &intf->MAC) : 0;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome int TraceRecordSpace = (mDNS_McastTracingEnabled && MDNS_TRACER) ? DNSOpt_Header_Space + DNSOpt_TraceData_Space : 0;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSBool useBackgroundTrafficClass = mDNSfalse; // set if we should use background traffic class
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome InitializeDNSMessage(&m->omsg.h, zeroID, QueryFlags);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (KnownAnswerList) verbosedebugf("SendQueries: KnownAnswerList set... Will continue from previous packet");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Start a new known-answer list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu32 answerforecast = OwnerRecordSpace + TraceRecordSpace; // Start by assuming we'll need at least enough space to put the Owner+Tracer Option
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Put query questions in this packet
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (q = m->Questions; q && q != m->NewQuestions; q=q->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSOpaque16IsZero(q->TargetQID) && (q->SendQNow == intf->InterfaceID))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("SendQueries: %s question for %##s (%s) at %d forecast total %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SuppressOnThisInterface(q->DupSuppress, intf) ? "Suppressing" : "Putting ",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->qname.c, DNSTypeName(q->qtype), queryptr - m->omsg.data, queryptr + answerforecast - m->omsg.data);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If interface is P2P type, verify that query should be sent over it.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!mDNSPlatformValidQuestionForInterface(q, intf))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("SendQueries: Not sending (%s) %##s on %s", DNSTypeName(q->qtype), q->qname.c, InterfaceNameForID(m, intf->InterfaceID));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->SendQNow = (q->InterfaceID || !q->SendOnAll) ? mDNSNULL : GetNextActiveInterfaceID(intf);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we're suppressing this question, or we successfully put it, update its SendQNow state
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if ((Suppress = SuppressOnThisInterface(q->DupSuppress, intf)) ||
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome BuildQuestion(m, intf, &m->omsg, &queryptr, q, &kalistptr, &answerforecast))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We successfully added the question to the packet. Make sure that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we also send the NSEC3 record if required. BuildQuestion accounted for
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the space.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: We don't suppress anonymous questions and hence Suppress should always
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("SendQueries: marking for question %##s, Suppress %d", q->qname.c, Suppress);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->SendQNow = (q->InterfaceID || !q->SendOnAll) ? mDNSNULL : GetNextActiveInterfaceID(intf);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // use background traffic class if any included question requires it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Put probe questions in this packet
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome mDNSBool ucast = (ar->ProbeCount >= DefaultProbeCountForTypeUnique-1) && m->CanReceiveUnicastOn5353 && intf->SupportsUnicastMDNSResponse;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu16 ucbit = (mDNSu16)(ucast ? kDNSQClass_UnicastResponse : 0);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu8 *const limit = m->omsg.data + (m->omsg.h.numQuestions ? NormalMaxDNSMessageData : AbsoluteMaxDNSMessageData);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We forecast: compressed name (2) type (2) class (2) TTL (4) rdlength (2) rdata (n)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu32 forecast = answerforecast + 12 + ar->resrec.rdestimate;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu8 *newptr = putQuestion(&m->omsg, queryptr, limit - forecast, ar->resrec.name, kDNSQType_ANY, (mDNSu16)(ar->resrec.rrclass | ucbit));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ar->SendRNow = (ar->resrec.InterfaceID) ? mDNSNULL : GetNextActiveInterfaceID(intf);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome verbosedebugf("SendQueries: Put Question %##s (%s) probecount %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ar->resrec.name->c, DNSTypeName(ar->resrec.rrtype), ar->ProbeCount);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Put our known answer list (either new one from this question or questions, or remainder of old one from last time)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu32 SecsSinceRcvd = ((mDNSu32)(m->timenow - ka->TimeRcvd)) / mDNSPlatformOneSecond;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu8 *newptr = PutResourceRecordTTLWithLimit(&m->omsg, queryptr, &m->omsg.h.numAnswers, &ka->resrec, ka->resrec.rroriginalttl - SecsSinceRcvd,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->omsg.data + NormalMaxDNSMessageData - OwnerRecordSpace - TraceRecordSpace);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome verbosedebugf("SendQueries: Put %##s (%s) at %d - %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ka->resrec.name->c, DNSTypeName(ka->resrec.rrtype), queryptr - m->omsg.data, newptr - m->omsg.data);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we ran out of space and we have more than one question in the packet, that's an error --
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we shouldn't have put more than one question if there was a risk of us running out of space.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("SendQueries: Put %d answers; No more space for known answers", m->omsg.h.numAnswers);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu8 *newptr = PutResourceRecord(&m->omsg, queryptr, &m->omsg.h.numAuthorities, &ar->resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else LogMsg("SendQueries: How did we fail to have space for the Update record %s", ARDisplayString(m,ar));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q->AnonInfo && q->AnonInfo->SendNow == intf->InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu8 *newptr = PutResourceRecord(&m->omsg, queryptr, &m->omsg.h.numAuthorities, q->AnonInfo->nsec3RR);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("SendQueries: Added NSEC3 record %s on InterfaceID %p", RRDisplayString(m, q->AnonInfo->nsec3RR), intf->InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("SendQueries: ERROR!! Cannot add NSEC3 record %s on InterfaceID %p", RRDisplayString(m, q->AnonInfo->nsec3RR), intf->InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we have data to send, add OWNER/TRACER/OWNER+TRACER option if necessary, then send packet
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetupResourceRecord(&opt, mDNSNULL, mDNSInterface_Any, kDNSType_OPT, kStandardTTL, kDNSRecordTypeKnownUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome opt.resrec.rdlength += sizeof(rdataOPT); // Two options in this OPT record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SetupOwnerOpt(m, intf, &opt.resrec.rdata->u.opt[0]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SetupTracerOpt(m, &opt.resrec.rdata->u.opt[1]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SetupOwnerOpt(m, intf, &opt.resrec.rdata->u.opt[0]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SetupTracerOpt(m, &opt.resrec.rdata->u.opt[0]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("SendQueries putting %s %s: %s %s", OwnerRecordSpace ? "OWNER" : "", TraceRecordSpace ? "TRACER" : "", intf->ifname, ARDisplayString(m, &opt));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome queryptr = PutResourceRecordTTLWithLimit(&m->omsg, queryptr, &m->omsg.h.numAdditionals,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome &opt.resrec, opt.resrec.rroriginalttl, m->omsg.data + AbsoluteMaxDNSMessageData);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("SendQueries: How did we fail to have space for %s %s OPT record (%d/%d/%d/%d) %s", OwnerRecordSpace ? "OWNER" : "", TraceRecordSpace ? "TRACER" : "",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->omsg.h.numQuestions, m->omsg.h.numAnswers, m->omsg.h.numAuthorities, m->omsg.h.numAdditionals, ARDisplayString(m, &opt));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (queryptr > m->omsg.data + NormalMaxDNSMessageData)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->omsg.h.numQuestions != 1 || m->omsg.h.numAnswers != 0 || m->omsg.h.numAuthorities != 1 || m->omsg.h.numAdditionals != 1)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("SendQueries: Why did we generate oversized packet with %s %s OPT record %p %p %p (%d/%d/%d/%d) %s", OwnerRecordSpace ? "OWNER" : "",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome TraceRecordSpace ? "TRACER" : "", m->omsg.data, m->omsg.data + NormalMaxDNSMessageData, queryptr, m->omsg.h.numQuestions, m->omsg.h.numAnswers,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->omsg.h.numAuthorities, m->omsg.h.numAdditionals, ARDisplayString(m, &opt));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((m->omsg.h.flags.b[0] & kDNSFlag0_TC) && m->omsg.h.numQuestions > 1)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("SendQueries: Should not have more than one question (%d) in a truncated packet", m->omsg.h.numQuestions);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("SendQueries: Sending %d Question%s %d Answer%s %d Update%s on %p",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->omsg.h.numQuestions, m->omsg.h.numQuestions == 1 ? "" : "s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->omsg.h.numAnswers, m->omsg.h.numAnswers == 1 ? "" : "s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->omsg.h.numAuthorities, m->omsg.h.numAuthorities == 1 ? "" : "s", intf->InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (intf->IPv4Available) mDNSSendDNSMessage(m, &m->omsg, queryptr, intf->InterfaceID, mDNSNULL, &AllDNSLinkGroup_v4, MulticastDNSPort, mDNSNULL, mDNSNULL, useBackgroundTrafficClass);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (intf->IPv6Available) mDNSSendDNSMessage(m, &m->omsg, queryptr, intf->InterfaceID, mDNSNULL, &AllDNSLinkGroup_v6, MulticastDNSPort, mDNSNULL, mDNSNULL, useBackgroundTrafficClass);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!m->SuppressSending) m->SuppressSending = NonZeroTime(m->timenow + (mDNSPlatformOneSecond+9)/10);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome { LogMsg("SendQueries exceeded loop limit %d: giving up", pktcount); break; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // There might be more records left in the known answer list, or more questions to send
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // on this interface, so go around one more time and try again.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else // Nothing more to send on this interface; go to next
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const NetworkInterfaceInfo *next = GetFirstActiveInterface(intf->next);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const char *const msg = next ? "SendQueries: Nothing more on %p; moving to %p" : "SendQueries: Nothing more on %p";
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 4. Final housekeeping
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 4a. Debugging check: Make sure we announced all our records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ar->ARType != AuthRecordLocalOnly && ar->ARType != AuthRecordP2P)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("SendQueries: No active interface %d to send probe: %d %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (uint32_t)ar->SendRNow, (uint32_t)ar->resrec.InterfaceID, ARDisplayString(m, ar));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 4b. When we have lingering cache records that we're keeping around for a few seconds in the hope
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // that their interface which went away might come back again, the logic will want to send queries
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // for those records, but we can't because their interface isn't here any more, so to keep the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // state machine ticking over we just pretend we did so.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the interface does not come back in time, the cache record will expire naturally
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (cr->CRActiveQuestion && cr->UnansweredQueries < MaxUnansweredQueries)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->timenow + TicksTTL(cr)/50 - cr->NextRequiredQuery >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 4c. Debugging check: Make sure we sent all our planned questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Do this AFTER the lingering cache records check above, because that will prevent spurious warnings for questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we legitimately couldn't send because the interface is no longer available
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (x = m->NewQuestions; x; x=x->next) if (x == q) break; // Check if this question is a NewQuestion
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("SendQueries: No active interface %d to send %s question: %d %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (uint32_t)q->SendQNow, x ? "new" : "old", (uint32_t)q->InterfaceID, q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void SendWakeup(mDNS *const m, mDNSInterfaceID InterfaceID, mDNSEthAddr *EthAddr, mDNSOpaque48 *password)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome NetworkInterfaceInfo *intf = FirstInterfaceForID(m, InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!intf) { LogMsg("SendARP: No interface with InterfaceID %p found", InterfaceID); return; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x00 Destination address
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x06 Source address (Note: Since we don't currently set the BIOCSHDRCMPLT option, BPF will fill in the real interface address for us)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x0C Ethertype (0x0842)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x0E Wakeup sync sequence
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x14 Wakeup data
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (j=0; j<16; j++) for (i=0; i<6; i++) *ptr++ = EthAddr->b[i];
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 0x74 Password
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformSendRawPacket(m->omsg.data, ptr, InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For Ethernet switches that don't flood-foward packets with unknown unicast destination MAC addresses,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // broadcast is the only reliable way to get a wakeup packet to the intended target machine.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For 802.11 WPA networks, where a sleeping target machine may have missed a broadcast/multicast
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // key rotation, unicast is the only way to get a wakeup packet to the intended target machine.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // So, we send one of each, unicast first, then broadcast second.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformSendRawPacket(m->omsg.data, ptr, InterfaceID);
4b22b9337f359bfd063322244f5336cc7c6ffcfars// ***************************************************************************
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Whenever a question is answered, reset its state so that we don't query
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// the network repeatedly. This happens first time when we answer the question and
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// and later when we refresh the cache.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void ResetQuestionState(mDNS *const m, DNSQuestion *q)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Reset unansweredQueries so that we don't penalize this server later when we
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // start sending queries when the cache expires.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("ResetQuestionState: Set MaxQuestionInterval for %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Note: AnswerCurrentQuestionWithResourceRecord can call a user callback, which may change the record list and/or question list.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Any code walking either list must use the m->CurrentQuestion (and possibly m->CurrentRecord) mechanism to protect against this.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// In fact, to enforce this, the routine will *only* answer the question currently pointed to by m->CurrentQuestion,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// which will be auto-advanced (possibly to NULL) if the client callback cancels the question.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void AnswerCurrentQuestionWithResourceRecord(mDNS *const m, CacheRecord *const rr, const QC_result AddRecord)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSBool followcname = FollowCNAME(q, &rr->resrec, AddRecord);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome verbosedebugf("AnswerCurrentQuestionWithResourceRecord:%4lu %s TTL %d %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->CurrentAnswers, AddRecord ? "Add" : "Rmv", rr->resrec.rroriginalttl, CRDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When the response for the question was validated, the entire rrset was validated. If we deliver
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // a RMV for a single record in the rrset, we invalidate the response. If we deliver another add
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // in the future, we will do the revalidation again.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Also, if we deliver an ADD for a negative cache record and it has no NSEC/NSEC3, the ValidationStatus needs
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to be reset. This happens normally when we deliver a "secure" negative response followed by an insecure
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // negative response which can happen e.g., when disconnecting from network that leads to a negative response
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // due to no DNS servers. As we don't deliver RMVs for negative responses that were delivered before, we need
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to do it on the next ADD of a negative cache record. This ADD could be the result of a timeout, no DNS servers
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // etc. in which case we need to reset the state to make sure we don't deliver them as secure. If this is
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // a real negative response, we would reset the state here and validate the results at the end of this function.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // or the real response again if we purge the cache.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q->ValidationRequired && ((AddRecord == QC_rmv) ||
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (rr->resrec.RecordType == kDNSRecordTypePacketNegative && (AddRecord == QC_add))))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Normally we don't send out the unicast query if we have answered using our local only auth records e.g., /etc/hosts.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // But if the query for "A" record has a local answer but query for "AAAA" record has no local answer, we might
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // send the AAAA query out which will come back with CNAME and will also answer the "A" query. To prevent that,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we check to see if that query already has a unique local answer.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("AnswerCurrentQuestionWithResourceRecord: Question %p %##s (%s) not answering with record %s due to "
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome "LOAddressAnswers %d", q, q->qname.c, DNSTypeName(q->qtype), ARDisplayString(m, rr),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the query is suppressed, then we don't want to answer from the cache. But if this query is
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // supposed to time out, we still want to callback the clients. We do this only for TimeoutQuestions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // that are timing out, which we know are answered with negative cache record when timing out.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!q->TimeoutQuestion || rr->resrec.RecordType != kDNSRecordTypePacketNegative || (m->timenow - q->StopTime < 0))
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if ((AddRecord == QC_add) && Question_uDNS(q) && (!q->metrics.answered || (q->metrics.querySendCount > 0)))
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome queryName = metrics->originalQName ? metrics->originalQName : &q->qname;
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome responseLatencyMs = ((m->timenow - metrics->firstQueryTime) * 1000) / mDNSPlatformOneSecond;
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome isForCellular = (q->qDNSServer && q->qDNSServer->cellIntf);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome MetricsUpdateUDNSStats(queryName, mDNStrue, metrics->querySendCount, responseLatencyMs, isForCellular);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: Use caution here. In the case of records with rr->DelayDelivery set, AnswerCurrentQuestionWithResourceRecord(... mDNStrue)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // may be called twice, once when the record is received, and again when it's time to notify local clients.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If any counters or similar are added here, care must be taken to ensure that they are not double-incremented by this.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (AddRecord == QC_add && !q->DuplicateOf && rr->CRActiveQuestion != q)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!rr->CRActiveQuestion) m->rrcache_active++; // If not previously active, increment rrcache_active count
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("AnswerCurrentQuestionWithResourceRecord: Updating CRActiveQuestion from %p to %p for cache record %s, CurrentAnswer %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->CRActiveQuestion, q, CRDisplayString(m,rr), q->CurrentAnswers);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->CRActiveQuestion = q; // We know q is non-null
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this is:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (a) a no-cache add, where we've already done at least one 'QM' query, or
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (b) a normal add, where we have at least one unique-type answer,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then there's no need to keep polling the network.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (If we have an answer in the cache, then we'll automatically ask again in time to stop it expiring.)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We do this for mDNS questions and uDNS one-shot questions, but not for
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // uDNS LongLived questions, because that would mess up our LLQ lease renewal timing.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((AddRecord == QC_addnocache && !q->RequestUnicast) ||
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (AddRecord == QC_add && (q->ExpectUnique || (rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask))))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ActiveQuestion(q) && (mDNSOpaque16IsZero(q->TargetQID) || !q->LongLived))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->DelayDelivery) return; // We'll come back later when CacheRecordDeferredAdd() calls us
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Only deliver negative answers if client has explicitly requested them except when we are forcing a negative response
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // for the purpose of retrying search domains/timeout OR the question is suppressed
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType == kDNSRecordTypePacketNegative || (q->qtype != kDNSType_NSEC && RRAssertsNonexistence(&rr->resrec, q->qtype)))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!AddRecord || (AddRecord != QC_suppressed && AddRecord != QC_forceresponse && !q->ReturnIntermed)) return;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For CNAME results to non-CNAME questions, only inform the client if they explicitly requested that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q->QuestionCallback && !q->NoAnswer && (!followcname || q->ReturnIntermed))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_DropLockBeforeCallback(); // Allow client (and us) to legally make mDNS API calls
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q->qtype != kDNSType_NSEC && RRAssertsNonexistence(&rr->resrec, q->qtype))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome MakeNegativeCacheRecord(m, &neg, &q->qname, q->qnamehash, q->qtype, q->qclass, 1, rr->resrec.InterfaceID, q->qDNSServer);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->QuestionCallback(m, q, &neg.resrec, AddRecord);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->QuestionCallback(m, q, &rr->resrec, AddRecord);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this is an "Add" operation and this question needs validation, validate the response.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // In the case of negative responses, extra care should be taken. Negative cache records are
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // used for many purposes. For example,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1) Suppressing questions (SuppressUnusable)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2) Timeout questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 3) The name does not exist
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 4) No DNS servers are available and we need a quick response for the application
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (1) and (2) are handled by "QC_add" check as AddRecord would be "QC_forceresponse" or "QC_suppressed"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // in that case. For (3), it is possible that we don't get nsecs back but we still need to call
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // VerifySignature so that we can deliver the appropriate DNSSEC result. There is no point in verifying
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // signature for (4) and hence the explicit check for q->qDNSServer.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentQuestion == q && (AddRecord == QC_add) && !q->ValidatingResponse && q->ValidationRequired &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->ValidationState == DNSSECValRequired && q->qDNSServer)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Treat it as callback call as that's what dnssec code expects
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_DropLockBeforeCallback(); // Allow client (and us) to legally make mDNS API calls
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: Proceed with caution here because client callback function is allowed to do anything,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // including starting/stopping queries, registering/deregistering records, etc.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we get a CNAME back while we are validating the response (i.e., CNAME for DS, DNSKEY, RRSIG),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // don't follow them. If it is a ValidationRequired question, wait for the CNAME to be validated
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // first before following it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!ValidatingQuestion(q) && followcname && m->CurrentQuestion == q)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnswerQuestionByFollowingCNAME(m, q, &rr->resrec);
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void CacheRecordDeferredAdd(mDNS *const m, CacheRecord *rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("CacheRecordDeferredAdd ERROR m->CurrentQuestion already set: %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (m->CurrentQuestion && m->CurrentQuestion != m->NewQuestions)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ResourceRecordAnswersQuestion(&rr->resrec, q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnswerCurrentQuestionWithResourceRecord(m, rr, QC_add);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentQuestion == q) // If m->CurrentQuestion was not auto-advanced, do it ourselves now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSs32 CheckForSoonToExpireRecords(mDNS *const m, const domainname *const name, const mDNSu32 namehash, const mDNSu32 slot, mDNSBool *purge)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSs32 threshhold = m->timenow + mDNSPlatformOneSecond; // See if there are any records expiring within one second
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheGroup *cg = CacheGroupForName(m, slot, namehash, name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If there are records that will expire soon, there are cases that need delayed
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // delivery of events:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1) A new cache entry is about to be added as a replacement. The caller needs to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // deliver a RMV (for the current old entry) followed by ADD (for the new entry).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // It needs to schedule the timer for the next cache expiry (ScheduleNextCacheCheckTime),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // so that the cache entry can be purged (purging causes the RMV followed by ADD)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2) A new question is about to be answered and the caller needs to know whether it's
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // scheduling should be delayed so that the question is not answered with this record.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Instead of delivering an ADD (old entry) followed by RMV (old entry) and another ADD
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (new entry), a single ADD can be delivered by delaying the scheduling of the question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // immediately.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When the unicast cache record is created, it's TTL has been extended beyond its value
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // given in the resource record (See RRAdjustTTL). If it is in the "extended" time, the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // cache is already expired and we set "purge" to indicate that. When "purge" is set, the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // return value of the function should be ignored by the callers.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: For case (1), "purge" argument is NULL and hence the following checks are skipped.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // It is okay to skip in that case because the cache records have been set to expire almost
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // immediately and the extended time does not apply.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Also, if there is already an active question we don't try to optimize as purging the cache
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // would end up delivering RMV for the active question and hence we avoid that.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (purge && !rr->resrec.InterfaceID && !rr->CRActiveQuestion && rr->resrec.rroriginalttl)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu32 uTTL = RRUnadjustedTTL(rr->resrec.rroriginalttl);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->timenow - (rr->TimeRcvd + ((mDNSs32)uTTL * mDNSPlatformOneSecond)) >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("CheckForSoonToExpireRecords: %s: rroriginalttl %u, unadjustedTTL %u, currentTTL %u",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CRDisplayString(m, rr), rr->resrec.rroriginalttl, uTTL, (m->timenow - rr->TimeRcvd)/mDNSPlatformOneSecond);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (threshhold - RRExpireTime(rr) >= 0) // If we have records about to expire within a second
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (delay - RRExpireTime(rr) < 0) // then delay until after they've been deleted
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// CacheRecordAdd is only called from CreateNewCacheEntry, *never* directly as a result of a client API call.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// If new questions are created as a result of invoking client callbacks, they will be added to
4b22b9337f359bfd063322244f5336cc7c6ffcfars// the end of the question list, and m->NewQuestions will be set to indicate the first new question.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// rr is a new CacheRecord just received into our cache
4b22b9337f359bfd063322244f5336cc7c6ffcfars// (kDNSRecordTypePacketAns/PacketAnsUnique/PacketAdd/PacketAddUnique).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Note: CacheRecordAdd calls AnswerCurrentQuestionWithResourceRecord which can call a user callback,
4b22b9337f359bfd063322244f5336cc7c6ffcfars// which may change the record list and/or question list.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void CacheRecordAdd(mDNS *const m, CacheRecord *rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We stop when we get to NewQuestions -- if we increment their CurrentAnswers/LargeAnswers/UniqueAnswers
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // counters here we'll end up double-incrementing them when we do it again in AnswerNewQuestion().
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (q = m->Questions; q && q != m->NewQuestions; q=q->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ResourceRecordAnswersQuestion(&rr->resrec, q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this question is one that's actively sending queries, and it's received ten answers within one
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // second of sending the last query packet, then that indicates some radical network topology change,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // so reset its exponential backoff back to the start. We must be at least at the eight-second interval
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to do this. If we're at the four-second interval, or less, there's not much benefit accelerating
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // because we will anyway send another query within a few seconds. The first reset query is sent out
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // randomized over the next four seconds to reduce possible synchronization between machines.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSOpaque16IsZero(q->TargetQID) && ActiveQuestion(q) && ++q->RecentAnswerPkts >= 10 &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->ThisQInterval > InitialQuestionInterval * QuestionIntervalStep3 && m->timenow - q->LastQTxTime < mDNSPlatformOneSecond)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("CacheRecordAdd: %##s (%s) got immediate answer burst (%d); restarting exponential backoff sequence (%d)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->qname.c, DNSTypeName(q->qtype), q->RecentAnswerPkts, q->ThisQInterval);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->LastQTime = m->timenow - InitialQuestionInterval + (mDNSs32)mDNSRandom((mDNSu32)mDNSPlatformOneSecond*4);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome verbosedebugf("CacheRecordAdd %p %##s (%s) %lu %#a:%d question %p", rr, rr->resrec.name->c,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome DNSTypeName(rr->resrec.rrtype), rr->resrec.rroriginalttl, rr->resrec.rDNSServer ?
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome &rr->resrec.rDNSServer->addr : mDNSNULL, mDNSVal16(rr->resrec.rDNSServer ?
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.rdlength > SmallRecordLimit) q->LargeAnswers++;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask) q->UniqueAnswers++;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("CacheRecordAdd: %##s (%s) has %d answers; shedding records to resist DOS attack",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->qname.c, DNSTypeName(q->qtype), q->CurrentAnswers);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("CacheRecordAdd ERROR m->CurrentQuestion already set: %##s (%s)", m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (m->CurrentQuestion && m->CurrentQuestion != m->NewQuestions)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ResourceRecordAnswersQuestion(&rr->resrec, q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnswerCurrentQuestionWithResourceRecord(m, rr, QC_add);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentQuestion == q) // If m->CurrentQuestion was not auto-advanced, do it ourselves now
4b22b9337f359bfd063322244f5336cc7c6ffcfars// NoCacheAnswer is only called from mDNSCoreReceiveResponse, *never* directly as a result of a client API call.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// If new questions are created as a result of invoking client callbacks, they will be added to
4b22b9337f359bfd063322244f5336cc7c6ffcfars// the end of the question list, and m->NewQuestions will be set to indicate the first new question.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// rr is a new CacheRecord just received from the wire (kDNSRecordTypePacketAns/AnsUnique/Add/AddUnique)
4b22b9337f359bfd063322244f5336cc7c6ffcfars// but we don't have any place to cache it. We'll deliver question 'add' events now, but we won't have any
4b22b9337f359bfd063322244f5336cc7c6ffcfars// way to deliver 'remove' events in future, nor will we be able to include this in known-answer lists,
4b22b9337f359bfd063322244f5336cc7c6ffcfars// so we immediately bump ThisQInterval up to MaxQuestionInterval to avoid pounding the network.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Note: NoCacheAnswer calls AnswerCurrentQuestionWithResourceRecord which can call a user callback,
4b22b9337f359bfd063322244f5336cc7c6ffcfars// which may change the record list and/or question list.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void NoCacheAnswer(mDNS *const m, CacheRecord *rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("No cache space: Delivering non-cached result for %##s", m->rec.r.resrec.name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("NoCacheAnswer ERROR m->CurrentQuestion already set: %##s (%s)", m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We do this for *all* questions, not stopping when we get to m->NewQuestions,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // since we're not caching the record and we'll get no opportunity to do this later
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ResourceRecordAnswersQuestion(&rr->resrec, q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnswerCurrentQuestionWithResourceRecord(m, rr, QC_addnocache); // QC_addnocache means "don't expect remove events for this"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentQuestion == q) // If m->CurrentQuestion was not auto-advanced, do it ourselves now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// CacheRecordRmv is only called from CheckCacheExpiration, which is called from mDNS_Execute.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Note that CacheRecordRmv is *only* called for records that are referenced by at least one active question.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// If new questions are created as a result of invoking client callbacks, they will be added to
4b22b9337f359bfd063322244f5336cc7c6ffcfars// the end of the question list, and m->NewQuestions will be set to indicate the first new question.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// rr is an existing cache CacheRecord that just expired and is being deleted
4b22b9337f359bfd063322244f5336cc7c6ffcfars// (kDNSRecordTypePacketAns/PacketAnsUnique/PacketAdd/PacketAddUnique).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Note: CacheRecordRmv calls AnswerCurrentQuestionWithResourceRecord which can call a user callback,
4b22b9337f359bfd063322244f5336cc7c6ffcfars// which may change the record list and/or question list.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void CacheRecordRmv(mDNS *const m, CacheRecord *rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("CacheRecordRmv ERROR m->CurrentQuestion already set: %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We stop when we get to NewQuestions -- for new questions their CurrentAnswers/LargeAnswers/UniqueAnswers counters
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // will all still be zero because we haven't yet gone through the cache counting how many answers we have for them.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (m->CurrentQuestion && m->CurrentQuestion != m->NewQuestions)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When a question enters suppressed state, we generate RMV events and generate a negative
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // response. A cache may be present that answers this question e.g., cache entry generated
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // before the question became suppressed. We need to skip the suppressed questions here as
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the RMV event has already been generated.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!QuerySuppressed(q) && ResourceRecordAnswersQuestion(&rr->resrec, q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome verbosedebugf("CacheRecordRmv %p %s", rr, CRDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("CacheRecordRmv ERROR!!: How can CurrentAnswers already be zero for %p %##s (%s) DNSServer %#a:%d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q, q->qname.c, DNSTypeName(q->qtype), q->qDNSServer ? &q->qDNSServer->addr : mDNSNULL,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSVal16(q->qDNSServer ? q->qDNSServer->port : zp));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.rdlength > SmallRecordLimit) q->LargeAnswers--;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask) q->UniqueAnswers--;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we have dropped below the answer threshold for this mDNS question,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // restart the queries at InitialQuestionInterval.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSOpaque16IsZero(q->TargetQID) && (q->BrowseThreshold > 0) && (q->CurrentAnswers < q->BrowseThreshold))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("CacheRecordRmv: (%s) %##s dropped below threshold of %d answers",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome DNSTypeName(q->qtype), q->qname.c, q->BrowseThreshold);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.rdata->MaxRDLength) // Never generate "remove" events for negative results
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("CacheRecordRmv: Last answer for %##s (%s) expired from cache; will reconfirm antecedents",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ReconfirmAntecedents(m, &q->qname, q->qnamehash, 0);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnswerCurrentQuestionWithResourceRecord(m, rr, QC_rmv);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentQuestion == q) // If m->CurrentQuestion was not auto-advanced, do it ourselves now
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void ReleaseCacheEntity(mDNS *const m, CacheEntity *e)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#if APPLE_OSX_mDNSResponder && MACOSX_MDNS_MALLOC_DEBUGGING >= 1
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome unsigned int i;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<sizeof(*e); i++) ((char*)e)[i] = 0xFF;
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void ReleaseCacheGroup(mDNS *const m, CacheGroup **cp)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome //LogMsg("ReleaseCacheGroup: Releasing CacheGroup for %p, %##s", (*cp)->name->c, (*cp)->name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("ERROR: (*cp)->members == mDNSNULL but (*cp)->rrcache_tail != &(*cp)->members)");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome //if ((*cp)->name != (domainname*)((*cp)->namestorage))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // LogMsg("ReleaseCacheGroup: %##s, %p %p", (*cp)->name->c, (*cp)->name, (domainname*)((*cp)->namestorage));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((*cp)->name != (domainname*)((*cp)->namestorage)) mDNSPlatformMemFree((*cp)->name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void ReleaseAdditionalCacheRecords(mDNS *const m, CacheRecord **rp)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.rdata && rr->resrec.rdata != (RData*)&rr->smallrdatastorage)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // NSEC or SOA records that are not added to the CacheGroup do not share the name
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // of the CacheGroup.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("ReleaseAdditionalCacheRecords: freeing cached record %##s (%s)", rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Don't count the NSEC3 records used by anonymous browse/reg
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rrcache_totalused_unicast -= rr->resrec.rdlength;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome BumpDNSSECStats(m, kStatsActionDecrement, kStatsTypeMemoryUsage, rr->resrec.rdlength);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void ReleaseCacheRecord(mDNS *const m, CacheRecord *r)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome //LogMsg("ReleaseCacheRecord: Releasing %s", CRDisplayString(m, r));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (r->resrec.rdata && r->resrec.rdata != (RData*)&r->smallrdatastorage) mDNSPlatformMemFree(r->resrec.rdata);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // It is okay to have this printed for NSEC/NSEC3s
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ReleaseCacheRecord: ERROR!! cg NULL for %##s (%s)", r->resrec.name->c, DNSTypeName(r->resrec.rrtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When NSEC records are not added to the cache, it is usually cached at the "nsec" list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // of the CacheRecord. But sometimes they may be freed without adding to the "nsec" list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (which is handled below) and in that case it should be freed here.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (r->resrec.name && cg && r->resrec.name != cg->name)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("ReleaseCacheRecord: freeing %##s (%s)", r->resrec.name->c, DNSTypeName(r->resrec.rrtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("ReleaseCacheRecord: freeing AnonInfo for %##s (%s)", r->resrec.name->c, DNSTypeName(r->resrec.rrtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rrcache_totalused_unicast -= r->resrec.rdlength;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome BumpDNSSECStats(m, kStatsActionDecrement, kStatsTypeMemoryUsage, r->resrec.rdlength);
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Note: We want to be careful that we deliver all the CacheRecordRmv calls before delivering
4b22b9337f359bfd063322244f5336cc7c6ffcfars// CacheRecordDeferredAdd calls. The in-order nature of the cache lists ensures that all
4b22b9337f359bfd063322244f5336cc7c6ffcfars// callbacks for old records are delivered before callbacks for newer records.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void CheckCacheExpiration(mDNS *const m, const mDNSu32 slot, CacheGroup *const cg)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->lock_rrcache) { LogMsg("CheckCacheExpiration ERROR! Cache already locked!"); return; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->timenow - event >= 0) // If expired, delete it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome verbosedebugf("CheckCacheExpiration: Deleting%7d %7d %p %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->timenow - rr->TimeRcvd, rr->resrec.rroriginalttl, rr->CRActiveQuestion, CRDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->CRActiveQuestion) // If this record has one or more active questions, tell them it's going away
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When a cache record is about to expire, we expect to do four queries at 80-82%, 85-87%, 90-92% and
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then 95-97% of the TTL. If the DNS server does not respond, then we will remove the cache entry
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // before we pick a new DNS server. As the question interval is set to MaxQuestionInterval, we may
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // not send out a query anytime soon. Hence, we need to reset the question interval. If this is
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // a normal deferred ADD case, then AnswerCurrentQuestionWithResourceRecord will reset it to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // MaxQuestionInterval. If we have inactive questions referring to negative cache entries,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // don't ressurect them as they will deliver duplicate "No such Record" ADD events
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!mDNSOpaque16IsZero(q->TargetQID) && !q->LongLived && ActiveQuestion(q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else // else, not expired; see if we need to query
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If waiting to delay delivery, do nothing until then
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->DelayDelivery && rr->DelayDelivery - m->timenow > 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->DelayDelivery) CacheRecordDeferredAdd(m, rr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->CRActiveQuestion && rr->UnansweredQueries < MaxUnansweredQueries)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->timenow - rr->NextRequiredQuery < 0) // If not yet time for next query
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome event = NextCacheCheckEvent(rr); // then just record when we want the next query
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else // else trigger our question to go out now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Set NextScheduledQuery to timenow so that SendQueries() will run.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // SendQueries() will see that we have records close to expiration, and send FEQs for them.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // After sending the query we'll increment UnansweredQueries and call SetNextCacheCheckTimeForRecord(),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // which will correctly update m->NextCacheCheck for us.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome verbosedebugf("CheckCacheExpiration:%6d %5d %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (event - m->timenow) / mDNSPlatformOneSecond, CacheCheckGracePeriod(rr), CRDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (cg->rrcache_tail != rp) verbosedebugf("CheckCacheExpiration: Updating CacheGroup tail from %p to %p", cg->rrcache_tail, rp);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// "LORecord" includes both LocalOnly and P2P record. This function assumes m->CurrentQuestion is pointing to "q".
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// If "CheckOnly" is set to "true", the question won't be answered but just check to see if there is an answer and
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// returns true if there is an answer.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// If "CheckOnly" is set to "false", the question will be answered if there is a LocalOnly/P2P record and
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// returns true to indicate the same.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool AnswerQuestionWithLORecord(mDNS *const m, DNSQuestion *q, mDNSBool checkOnly)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("AnswerQuestionWithLORecord ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ag = AuthGroupForName(&m->rrauth, slot, q->qnamehash, &q->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (m->CurrentRecord && m->CurrentRecord != ag->NewLocalOnlyRecords)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the question is mDNSInterface_LocalOnly, all records local to the machine should be used
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to answer the query. This is handled in AnswerNewLocalOnlyQuestion.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We handle mDNSInterface_Any and scoped questions here. See LocalOnlyRecordAnswersQuestion for more
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // details on how we handle this case. For P2P we just handle "Interface_Any" questions. For LocalOnly
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we handle both mDNSInterface_Any and scoped questions.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->ARType == AuthRecordLocalOnly || (rr->ARType == AuthRecordP2P && q->InterfaceID == mDNSInterface_Any))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("AnswerQuestionWithLORecord: question %##s (%s) answered by %s", q->qname.c, DNSTypeName(q->qtype),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnswerLocalQuestionWithLocalAuthRecord(m, rr, QC_add);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome break; // If callback deleted q, then we're finished here
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("AnswerQuestionWithLORecord: Question deleted while while answering LocalOnly record answers");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("AnswerQuestionWithLORecord: Question %p %##s (%s) answered using local auth records LOAddressAnswers %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q, q->qname.c, DNSTypeName(q->qtype), q->LOAddressAnswers);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Before we go check the cache and ship this query on the wire, we have to be sure that there are
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // no local records that could possibly answer this question. As we did not check the NewLocalRecords, we
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // need to just peek at them to see whether it will answer this question. If it would answer, pretend
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // that we answered. AnswerAllLocalQuestionsWithLocalAuthRecord will answer shortly. This happens normally
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // when we add new /etc/hosts entries and restart the question. It is a new question and also a new record.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (UniqueLocalOnlyRecord(lr) && LocalOnlyRecordAnswersQuestion(lr, q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("AnswerQuestionWithLORecord: Question %p %##s (%s) will be answered using new local auth records "
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome " LOAddressAnswers %d", q, q->qname.c, DNSTypeName(q->qtype), q->LOAddressAnswers);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Today, we suppress questions (not send them on the wire) for several reasons e.g.,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// AAAA query is suppressed because no IPv6 capability or PID is not allowed to make
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// DNS requests. We need to temporarily suspend the suppress status so that we can
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// deliver a negative response (AnswerCurrentQuestionWithResourceRecord does not answer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// suppressed questions) and reset it back. In the future, if there are other
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// reasons for suppressing the query, this function should be updated.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void AnswerSuppressedQuestion(mDNS *const m, DNSQuestion *q)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // make sure that QuerySuppressed() returns false
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome DNSQuestion *const q = m->NewQuestions; // Grab the question we're going to answer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheGroup *const cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome verbosedebugf("AnswerNewQuestion: Answering %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->NewQuestions != q) { LogInfo("AnswerNewQuestion: Question deleted while doing CheckCacheExpiration"); goto exit; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Advance NewQuestions to the next *after* calling CheckCacheExpiration, because if we advance it first
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then CheckCacheExpiration may give this question add/remove callbacks, and it's not yet ready for that.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Also, CheckCacheExpiration() calls CacheRecordDeferredAdd() and CacheRecordRmv(), which invoke
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // client callbacks, which may delete their own or any other question. Our mechanism for detecting
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // whether our current m->NewQuestions question got deleted by one of these callbacks is to store the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // value of m->NewQuestions in 'q' before calling CheckCacheExpiration(), and then verify afterwards
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // that they're still the same. If m->NewQuestions has changed (because mDNS_StopQuery_internal
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // advanced it), that means the question was deleted, so we no longer need to worry about answering
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // it (and indeed 'q' is now a dangling pointer, so dereferencing it at all would be bad, and the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // values we computed for slot and cg are now stale and relate to a question that no longer exists).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We can't use the usual m->CurrentQuestion mechanism for this because CacheRecordDeferredAdd() and
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // CacheRecordRmv() both use that themselves when walking the list of (non-new) questions generating callbacks.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Fortunately mDNS_StopQuery_internal auto-advances both m->CurrentQuestion *AND* m->NewQuestions when
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // deleting a question, so luckily we have an easy alternative way of detecting if our question got deleted.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->lock_rrcache) LogMsg("AnswerNewQuestion ERROR! Cache already locked!");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This should be safe, because calling the client's question callback may cause the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // question list to be modified, but should not ever cause the rrcache list to be modified.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the client's question callback deletes the question, then m->CurrentQuestion will
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // be advanced, and we'll exit out of the loop
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("AnswerNewQuestion ERROR m->CurrentQuestion already set: %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->CurrentQuestion = q; // Indicate which question we're answering, so we'll know if it gets deleted
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("AnswerNewQuestion: NoAnswer_Fail %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome MakeNegativeCacheRecord(m, &m->rec.r, &q->qname, q->qnamehash, q->qtype, q->qclass, 60, mDNSInterface_Any, q->qDNSServer);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->NoAnswer = NoAnswer_Normal; // Temporarily turn off answer suppression
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnswerCurrentQuestionWithResourceRecord(m, &m->rec.r, QC_addnocache);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Don't touch the question if it has been stopped already
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentQuestion == q) q->NoAnswer = NoAnswer_Fail; // Restore NoAnswer state
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("AnswerNewQuestion: Question deleted while generating NoAnswer_Fail response");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // See if we want to tell it about LocalOnly/P2P records. If we answered them using LocalOnly
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // or P2P record, then we are done.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (AnswerQuestionWithLORecord(m, q, mDNSfalse))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we are not supposed to answer this question, generate a negative response.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Temporarily suspend the SuppressQuery so that AnswerCurrentQuestionWithResourceRecord can answer the question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If it is a question trying to validate some response, it already checked the cache for a response. If it still
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // reissues a question it means it could not find the RRSIGs. So, we need to bypass the cache check and send
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the question out.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SameNameRecordAnswersQuestion(&rr->resrec, q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // SecsSinceRcvd is whole number of elapsed seconds, rounded down
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu32 SecsSinceRcvd = ((mDNSu32)(m->timenow - rr->TimeRcvd)) / mDNSPlatformOneSecond;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("AnswerNewQuestion: How is rr->resrec.rroriginalttl %lu <= SecsSinceRcvd %lu for %s %d %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rroriginalttl, SecsSinceRcvd, CRDisplayString(m, rr), m->timenow, rr->TimeRcvd);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome continue; // Go to next one in loop
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this record set is marked unique, then that means we can reasonably assume we have the whole set
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // -- we don't need to rush out on the network and query immediately to see if there are more answers out there
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask) || (q->ExpectUnique))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.rdlength > SmallRecordLimit) q->LargeAnswers++;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask) q->UniqueAnswers++;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnswerCurrentQuestionWithResourceRecord(m, rr, QC_add);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentQuestion != q) break; // If callback deleted q, then we're finished here
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (RRTypeIsAddressType(rr->resrec.rrtype) && RRTypeIsAddressType(q->qtype))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We don't use LogInfo for this "Question deleted" message because it happens so routinely that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // it's not remotely remarkable, and therefore unlikely to be of much help tracking down bugs.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentQuestion != q) { debugf("AnswerNewQuestion: Question deleted while giving cache answers"); goto exit; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Neither a local record nor a cache entry could answer this question. If this question need to be retried
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // with search domains, generate a negative response which will now retry after appending search domains.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the query was suppressed above, we already generated a negative response. When it gets unsuppressed,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we will retry with search domains.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!QuerySuppressed(q) && !AnsweredFromCache && q->RetryWithSearchDomains)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("AnswerNewQuestion: Generating response for retrying with search domains %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentQuestion != q) { debugf("AnswerNewQuestion: Question deleted while giving negative answer"); goto exit; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: When a query gets suppressed or retried with search domains, we de-activate the question.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Hence we don't execute the following block of code for those cases.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ShouldQueryImmediately && ActiveQuestion(q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("AnswerNewQuestion: ShouldQueryImmediately %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSOpaque16IsZero(q->TargetQID)) // For mDNS, spread packets to avoid a burst of simultaneous queries
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Compute random delay in the range 1-6 seconds, then divide by 50 to get 20-120ms
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->RandomQueryDelay = (mDNSPlatformOneSecond + mDNSRandom(mDNSPlatformOneSecond*5) - 1) / 50 + 1;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // IN ALL CASES make sure that m->NextScheduledQuery is set appropriately.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // In cases where m->NewQuestions->DelayAnswering is set, we may have delayed generating our
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // answers for this question until *after* its scheduled transmission time, in which case
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // m->NextScheduledQuery may now be set to 'never', and in that case -- even though we're *not* doing
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // ShouldQueryImmediately -- we still need to make sure we set m->NextScheduledQuery correctly.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// When a NewLocalOnlyQuestion is created, AnswerNewLocalOnlyQuestion runs though our ResourceRecords delivering any
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// appropriate answers, stopping if it reaches a NewLocalOnlyRecord -- these will be handled by AnswerAllLocalQuestionsWithLocalAuthRecord
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome DNSQuestion *q = m->NewLocalOnlyQuestions; // Grab the question we're going to answer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NewLocalOnlyQuestions = q->next; // Advance NewLocalOnlyQuestions to the next (if any)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("AnswerNewLocalOnlyQuestion: Answering %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("AnswerNewLocalOnlyQuestion ERROR m->CurrentQuestion already set: %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->CurrentQuestion = q; // Indicate which question we're answering, so we'll know if it gets deleted
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("AnswerNewLocalOnlyQuestion ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1. First walk the LocalOnly records answering the LocalOnly question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2. As LocalOnly questions should also be answered by any other Auth records local to the machine,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // walk the ResourceRecords list delivering the answers
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ag = AuthGroupForName(&m->rrauth, slot, q->qnamehash, &q->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (m->CurrentRecord && m->CurrentRecord != ag->NewLocalOnlyRecords)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnswerLocalQuestionWithLocalAuthRecord(m, rr, QC_add);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentQuestion != q) break; // If callback deleted q, then we're finished here
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (m->CurrentRecord && m->CurrentRecord != m->NewLocalRecords)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ResourceRecordAnswersQuestion(&rr->resrec, q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnswerLocalQuestionWithLocalAuthRecord(m, rr, QC_add);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentQuestion != q) break; // If callback deleted q, then we're finished here
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal CacheEntity *GetCacheEntity(mDNS *const m, const CacheGroup *const PreserveCG)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->lock_rrcache) { LogMsg("GetFreeCacheRR ERROR! Cache already locked!"); return(mDNSNULL); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we have no free records, ask the client layer to give us some more memory
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("GetFreeCacheRR: count mismatch: m->rrcache_totalused %lu != m->rrcache_size %lu",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We don't want to be vulnerable to a malicious attacker flooding us with an infinite
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // number of bogus records so that we keep growing our cache until the machine runs out of memory.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // To guard against this, if our cache grows above 512kB (approx 3168 records at 164 bytes each),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and we're actively using less than 1/32 of that cache, then we purge all the unused records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and recycle them, instead of allocating more memory.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->rrcache_size > 5000 && m->rrcache_size / 32 > m->rrcache_active)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("Possible denial-of-service attack in progress: m->rrcache_size %lu; m->rrcache_active %lu",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we still have no free records, recycle all the records we can.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Enumerating the entire cache is moderately expensive, so when we do it, we reclaim all the records we can in one pass.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (slot = 0; slot < CACHE_HASH_SLOTS; slot++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Records that answer still-active questions are not candidates for recycling
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Records that are currently linked into the CacheFlushRecords list may not be recycled, or we'll crash
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((*rp)->CRActiveQuestion || (*rp)->NextInCFList)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome verbosedebugf("GetFreeCacheRR: Updating rrcache_tail[%lu] from %p to %p", slot, (*cp)->rrcache_tail, rp);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((*cp)->members || (*cp)==PreserveCG) cp=&(*cp)->next;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("GetCacheEntity recycled %d records to reduce cache from %d to %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome oldtotalused - m->rrcache_totalused, oldtotalused, m->rrcache_totalused);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->rrcache_free) // If there are records in the free list, take one
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (++m->rrcache_totalused >= m->rrcache_report)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("RR Cache now using %ld objects", m->rrcache_totalused);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->rrcache_report < 100) m->rrcache_report += 10;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (m->rrcache_report < 1000) m->rrcache_report += 100;
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal CacheRecord *GetCacheRecord(mDNS *const m, CacheGroup *cg, mDNSu16 RDLength)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheRecord *r = (CacheRecord *)GetCacheEntity(m, cg);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome r->resrec.rdata = (RData*)&r->smallrdatastorage; // By default, assume we're usually going to be using local storage
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (RDLength > InlineCacheRDSize) // If RDLength is too big, allocate extra storage
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome r->resrec.rdata = (RData*)mDNSPlatformMemAllocate(sizeofRDataHeader + RDLength);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (r->resrec.rdata) r->resrec.rdata->MaxRDLength = r->resrec.rdlength = RDLength;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else { ReleaseCacheEntity(m, (CacheEntity*)r); r = mDNSNULL; }
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal CacheGroup *GetCacheGroup(mDNS *const m, const mDNSu32 slot, const ResourceRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheGroup *cg = (CacheGroup*)GetCacheEntity(m, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!cg) { LogMsg("GetCacheGroup: Failed to allocate memory for %##s", rr->name->c); return(mDNSNULL); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("GetCacheGroup: Failed to allocate name storage for %##s", rr->name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (CacheGroupForRecord(m, slot, rr)) LogMsg("GetCacheGroup: Already have CacheGroup for %##s", rr->name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (CacheGroupForRecord(m, slot, rr) != cg) LogMsg("GetCacheGroup: Not finding CacheGroup for %##s", rr->name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void mDNS_PurgeCacheResourceRecord(mDNS *const m, CacheRecord *rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Make sure we mark this record as thoroughly expired -- we don't ever want to give
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // a positive answer using an expired record (e.g. from an interface that has gone away).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We don't want to clear CRActiveQuestion here, because that would leave the record subject to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // summary deletion without giving the proper callback to any questions that are monitoring it.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // By setting UnansweredQueries to MaxUnansweredQueries we ensure it won't trigger any further expiration queries.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->TimeRcvd = m->timenow - mDNSPlatformOneSecond * 60;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_TimeNow called while holding mDNS lock. This is incorrect. Code protected by lock should just use m->timenow.");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!m->timenow) LogMsg("mDNS_TimeNow: m->mDNS_busy is %ld but m->timenow not set", m->mDNS_busy);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// To avoid pointless CPU thrash, we use SetSPSProxyListChanged(X) to record the last interface that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// had its Sleep Proxy client list change, and defer to actual BPF reconfiguration to mDNS_Execute().
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// (GetNextScheduledEvent() returns "now" when m->SPSProxyListChanged is set)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (m->SPSProxyListChanged && m->SPSProxyListChanged != (X)) mDNSPlatformUpdateProxyList(m, m->SPSProxyListChanged); \
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->SPSProxyListChanged = (X); } while(0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Called from mDNS_Execute() to expire stale proxy records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void CheckProxyRecords(mDNS *const m, AuthRecord *list)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType != kDNSRecordTypeDeregistering && rr->WakeUp.HMAC.l[0])
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If m->SPSSocket is NULL that means we're not acting as a sleep proxy any more,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // so we need to cease proxying for *all* records we may have, expired or not.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->SPSSocket && m->timenow - rr->TimeExpire < 0) // If proxy record not expired yet, update m->NextScheduledSPS
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else // else proxy record expired, so remove it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("CheckProxyRecords: Removing %d H-MAC %.6a I-MAC %.6a %d %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->ProxyRecords, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, rr->WakeUp.seq, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SetSPSProxyListChanged(rr->resrec.InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Don't touch rr after this -- memory may have been free'd
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Mustn't advance m->CurrentRecord until *after* mDNS_Deregister_internal, because
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // new records could have been added to the end of the list as a result of that call.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void CheckRmvEventsForLocalRecords(mDNS *const m)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->AnsweredLocalQ && rr->resrec.RecordType == kDNSRecordTypeDeregistering)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("CheckRmvEventsForLocalRecords: Generating local RMV events for %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnswerAllLocalQuestionsWithLocalAuthRecord(m, rr, QC_rmv);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentRecord == rr) // If rr still exists in list, restore its state now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.RecordType = kDNSRecordTypeDeregistering;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // SendResponses normally calls CompleteDeregistration after sending goodbyes.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For LocalOnly records, we don't do that and hence we need to do that here.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (RRLocalOnly(rr)) CompleteDeregistration(m, rr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentRecord == rr) // If m->CurrentRecord was not auto-advanced, do it ourselves now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NextScheduledStopTime = m->timenow + 0x3FFFFFFF;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("TimeoutQuestions ERROR m->CurrentQuestion already set: %##s (%s)", m->CurrentQuestion->qname.c,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("TimeoutQuestions: ERROR!! TimeoutQuestion not set, but StopTime set for %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("TimeoutQuestions: question %p %##s timed out, time %d", q, q->qname.c, m->timenow - q->StopTime);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->NextScheduledStopTime - q->StopTime > 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If m->CurrentQuestion wasn't modified out from under us, advance it now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We can't do this at the start of the loop because GenerateNegativeResponse
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // depends on having m->CurrentQuestion point to the right question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNSCoreFreeProxyRR(mDNS *const m)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AuthRecord *rrPtr = m->SPSRRSet, *rrNext = mDNSNULL;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("%s : Freeing stored sleep proxy A/AAAA records", __func__);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Lock(m); // Must grab lock before trying to read m->timenow
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // APPLE_OSX_mDNSResponder
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_Execute: ERROR m->CurrentQuestion already set: %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_Execute: ERROR m->CurrentRecord already set: %s", ARDisplayString(m, m->CurrentRecord));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1. If we're past the probe suppression time, we can clear it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->SuppressProbes && m->timenow - m->SuppressProbes >= 0) m->SuppressProbes = 0;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2. If it's been more than ten seconds since the last probe failure, we can clear the counter
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->NumFailedProbes && m->timenow - m->ProbeFailTime >= mDNSPlatformOneSecond * 10) m->NumFailedProbes = 0;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 3. Purge our cache of stale old records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->rrcache_size && m->timenow - m->NextCacheCheck >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (slot = 0; slot < CACHE_HASH_SLOTS; slot++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->timenow - m->rrcache_nextcheck[slot] >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rrcache_nextcheck[slot] = m->timenow + 0x3FFFFFFF;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("m->NextCacheCheck %4d Slot %3d %##s", numchecked, slot, *cp ? (*cp)->name : (domainname*)"\x04NULL");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Even if we didn't need to actually check this slot yet, still need to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // factor its nextcheck time into our overall NextCacheCheck value
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->NextCacheCheck - m->rrcache_nextcheck[slot] > 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NextCacheCheck = m->rrcache_nextcheck[slot];
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("m->NextCacheCheck %4d checked, next in %d", numchecked, m->NextCacheCheck - m->timenow);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CheckProxyRecords(m, m->DuplicateRecords); // Clear m->DuplicateRecords first, then m->ResourceRecords
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SetSPSProxyListChanged(mDNSNULL); // Perform any deferred BPF reconfiguration now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Check to see if we need to send any keepalives. Do this after we called CheckProxyRecords above
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // as records could have expired during that check
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Clear AnnounceOwner if necessary. (Do this *before* SendQueries() and SendResponses().)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->AnnounceOwner && m->timenow - m->AnnounceOwner >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->DelaySleep && m->timenow - m->DelaySleep >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("Re-sleep delay passed; now checking for Sleep Proxy Servers");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 4. See if we can answer any of our new local questions from the cache
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->NewQuestions->DelayAnswering && m->timenow - m->NewQuestions->DelayAnswering < 0) break;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (i >= 1000) LogMsg("mDNS_Execute: AnswerNewQuestion exceeded loop limit");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Make sure we deliver *all* local RMV events, and clear the corresponding rr->AnsweredLocalQ flags, *before*
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we begin generating *any* new ADD events in the m->NewLocalOnlyQuestions and m->NewLocalRecords loops below.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Walk the LocalOnly records and deliver the RMV events
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (ag = m->rrauth.rrauth_hash[slot]; ag; ag = ag->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentRecord) CheckRmvEventsForLocalRecords(m);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (i >= 1000) LogMsg("mDNS_Execute: m->LocalRemoveEvents exceeded loop limit");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; m->NewLocalOnlyQuestions && i<1000; i++) AnswerNewLocalOnlyQuestion(m);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (i >= 1000) LogMsg("mDNS_Execute: AnswerNewLocalOnlyQuestion exceeded loop limit");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<1000 && m->NewLocalRecords && m->NewLocalRecords != head; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_Execute: Delivering Add event with LocalAuthRecord %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnswerAllLocalQuestionsWithLocalAuthRecord(m, rr, QC_add);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we have just one record that is not ready, we don't have to unlink and
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // reinsert. As the NewLocalRecords will be NULL for this case, the loop will
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // terminate and set the NewLocalRecords to rr.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_Execute: Just one LocalAuthRecord %s, breaking out of the loop early", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (head != mDNSNULL || m->NewLocalRecords != mDNSNULL)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_Execute: ERROR!!: head %p, NewLocalRecords %p", head, m->NewLocalRecords);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AuthRecord **p = &m->ResourceRecords; // Find this record in our list of active records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_Execute: Skipping LocalAuthRecord %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // if this is the first record we are skipping, move to the end of the list.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // if we have already skipped records before, append it at the end.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (*p) *p = rr->next; // Cut this record from the list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else { LogMsg("mDNS_Execute: ERROR!! Cannot find record %s in ResourceRecords list", ARDisplayString(m, rr)); break; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (*p) p=&(*p)->next;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_Execute: Setting NewLocalRecords to %s", (head ? ARDisplayString(m, head) : "NULL"));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (i >= 1000) LogMsg("mDNS_Execute: m->NewLocalRecords exceeded loop limit");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Check to see if we have any new LocalOnly/P2P records to examine for delivering
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to our local questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (ag = m->rrauth.rrauth_hash[slot]; ag; ag = ag->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<100 && ag->NewLocalOnlyRecords; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ag->NewLocalOnlyRecords = ag->NewLocalOnlyRecords->next;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // LocalOnly records should always be ready as they never probe
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_Execute: Delivering Add event with LocalAuthRecord %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnswerAllLocalQuestionsWithLocalAuthRecord(m, rr, QC_add);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else LogMsg("mDNS_Execute: LocalOnlyRecord %s not ready", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We limit about 100 per AuthGroup that can be serviced at a time
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (i >= 100) LogMsg("mDNS_Execute: ag->NewLocalOnlyRecords exceeded loop limit");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 5. See what packets we need to send
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->mDNSPlatformStatus != mStatus_NoError || (m->SleepState == SleepState_Sleeping))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->mDNSPlatformStatus == mStatus_NoError && (m->SuppressSending == 0 || m->timenow - m->SuppressSending >= 0))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the platform code is ready, and we're not suppressing packet generation right now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then send our responses, probes, and questions.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We check the cache first, because there might be records close to expiring that trigger questions to refresh them.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We send queries next, because there might be final-stage probes that complete their probing here, causing
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // them to advance to announcing state, and we want those to be included in any announcements we send out.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Finally, we send responses, including the previously mentioned records that just completed probing.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 6. Send Query packets. This may cause some probing records to advance to announcing state
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->timenow - m->NextScheduledQuery >= 0 || m->timenow - m->NextScheduledProbe >= 0) SendQueries(m);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_Execute: SendQueries didn't send all its queries (%d - %d = %d) will try again in one second",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->timenow, m->NextScheduledQuery, m->timenow - m->NextScheduledQuery);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NextScheduledQuery = m->timenow + mDNSPlatformOneSecond;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (q = m->Questions; q && q != m->NewQuestions; q=q->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ActiveQuestion(q) && m->timenow - NextQSendTime(q) >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_Execute: SendQueries didn't send %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_Execute: SendQueries didn't send all its probes (%d - %d = %d) will try again in one second",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->timenow, m->NextScheduledProbe, m->timenow - m->NextScheduledProbe);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NextScheduledProbe = m->timenow + mDNSPlatformOneSecond;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 7. Send Response packets, including probing records just advanced to announcing state
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->timenow - m->NextScheduledResponse >= 0) SendResponses(m);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->timenow - m->NextScheduledResponse >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_Execute: SendResponses didn't send all its responses; will try again in one second");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NextScheduledResponse = m->timenow + mDNSPlatformOneSecond;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Clear RandomDelay values, ready to pick a new different value next time
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->NextScheduledStopTime && m->timenow - m->NextScheduledStopTime >= 0) TimeoutQuestions(m);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->NextSRVUpdate && m->timenow - m->NextSRVUpdate >= 0) UpdateAllSRVRecords(m);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->timenow - m->NextScheduledNATOp >= 0) CheckNATMappings(m);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->timenow - m->NextuDNSEvent >= 0) uDNS_Tasks(m);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note about multi-threaded systems:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // On a multi-threaded system, some other thread could run right after the mDNS_Unlock(),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // performing mDNS API operations that change our next scheduled event time.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // On multi-threaded systems (like the current Windows implementation) that have a single main thread
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // calling mDNS_Execute() (and other threads allowed to call mDNS API routines) it is the responsibility
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // of the mDNSPlatformUnlock() routine to signal some kind of stateful condition variable that will
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // signal whatever blocking primitive the main thread is using, so that it will wake up and execute one
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // more iteration of its loop, and immediately call mDNS_Execute() again. The signal has to be stateful
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // in the sense that if the main thread has not yet entered its blocking primitive, then as soon as it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // does, the state of the signal will be noticed, causing the blocking primitive to return immediately
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // without blocking. This avoids the race condition between the signal from the other thread arriving
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // just *before* or just *after* the main thread enters the blocking primitive.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // On multi-threaded systems (like the current Mac OS 9 implementation) that are entirely timer-driven,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // with no main mDNS_Execute() thread, it is the responsibility of the mDNSPlatformUnlock() routine to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // set the timer according to the m->NextScheduledEvent value, and then when the timer fires, the timer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // callback function should call mDNS_Execute() (and ignore the return value, which may already be stale
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // by the time it gets to the timer callback function).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Unlock(m); // Calling mDNS_Unlock is what gives m->NextScheduledEvent its new value
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ActiveQuestion(q) && !mDNSOpaque16IsZero(q->TargetQID) && q->LongLived && q->state == LLQ_Established)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // UNICAST_DISABLED
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool QuestionHasLocalAnswers(mDNS *const m, DNSQuestion *q)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ag = AuthGroupForName(&m->rrauth, slot, q->qnamehash, &q->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Filter the /etc/hosts records - LocalOnly, Unique, A/AAAA/CNAME
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (UniqueLocalOnlyRecord(rr) && LocalOnlyRecordAnswersQuestion(rr, q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("QuestionHasLocalAnswers: Question %p %##s (%s) has local answer %s", q, q->qname.c, DNSTypeName(q->qtype), ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// ActivateUnicastQuery() is called from three places:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// 1. When a new question is created
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// 2. On wake from sleep
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// 3. When the DNS configuration changes
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// In case 1 we don't want to mess with our established ThisQInterval and LastQTime (ScheduleImmediately is false)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// In cases 2 and 3 we do want to cause the question to be resent immediately (ScheduleImmediately is true)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void ActivateUnicastQuery(mDNS *const m, DNSQuestion *const question, mDNSBool ScheduleImmediately)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For now this AutoTunnel stuff is specific to Mac OS X.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // In the future, if there's demand, we may see if we can abstract it out cleanly into the platform layer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Even though BTMM client tunnels are only useful for AAAA queries, we need to treat v4 and v6 queries equally.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Otherwise we can get the situation where the A query completes really fast (with an NXDOMAIN result) and the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // caller then gives up waiting for the AAAA result while we're still in the process of setting up the tunnel.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // To level the playing field, we block both A and AAAA queries while tunnel setup is in progress, and then
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // returns results for both at the same time. If we are looking for the _autotunnel6 record, then skip this logic
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // as this would trigger looking up _autotunnel6._autotunnel6 and end up failing the original query.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (RRTypeIsAddressType(question->qtype) && PrivateQuery(question) &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome !SameDomainLabel(question->qname.c, (const mDNSu8 *)"\x0c_autotunnel6")&& question->QuestionCallback != AutoTunnelCallback)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // APPLE_OSX_mDNSResponder
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->qname.c, DNSTypeName(question->qtype), PrivateQuery(question) ? " (Private)" : "", ScheduleImmediately ? " ScheduleImmediately" : "");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (question->nta) { CancelGetZoneData(m, question->nta); question->nta = mDNSNULL; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (question->tcp) { DisposeTCPConn(question->tcp); question->tcp = mDNSNULL; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the question has local answers, then we don't want answers from outside
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ScheduleImmediately && !QuestionHasLocalAnswers(m, question))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->ThisQInterval = InitialQuestionInterval;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->LastQTime = m->timenow - question->ThisQInterval;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Caller should hold the lock
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void mDNSCoreRestartAddressQueries(mDNS *const m, mDNSBool SearchDomainsChanged, FlushCache flushCacheRecords,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CallbackBeforeStartQuery BeforeStartCallback, void *context)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1. Flush the cache records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2. Even though we may have purged the cache records above, before it can generate RMV event
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we are going to stop the question. Hence we need to deliver the RMV event before we
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // stop the question.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // CurrentQuestion is used by RmvEventsForQuestion below. While delivering RMV events, the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // application callback can potentially stop the current question (detected by CurrentQuestion) or
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *any* other question which could be the next one that we may process here. RestartQuestion
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // points to the "next" question which will be automatically advanced in mDNS_StopQuery_internal
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // if the "next" question is stopped while the CurrentQuestion is stopped
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNSCoreRestartAddressQueries: ERROR!! m->RestartQuestion already set: %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->RestartQuestion->qname.c, DNSTypeName(m->RestartQuestion->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // GetZoneData questions are referenced by other questions (original query that started the GetZoneData
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // question) through their "nta" pointer. Normally when the original query stops, it stops the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // GetZoneData question and also frees the memory (See CancelGetZoneData). If we stop the GetZoneData
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // question followed by the original query that refers to this GetZoneData question, we will end up
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // freeing the GetZoneData question and then start the "freed" question at the end.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreRestartAddressQueries: Skipping GetZoneDataQuestion %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // debug stuff, we just try to find the referencing question and don't do much with it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreRestartAddressQueries: Question %p %##s (%s) referring to GetZoneDataQuestion %p, not stopping", refq, refq->qname.c, DNSTypeName(refq->qtype), q);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This function is called when /etc/hosts changes and that could affect A, AAAA and CNAME queries
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q->qtype != kDNSType_A && q->qtype != kDNSType_AAAA && q->qtype != kDNSType_CNAME) continue;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the search domains did not change, then we restart all the queries. Otherwise, only
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // for queries for which we "might" have appended search domains ("might" because we may
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // find results before we apply search domains even though AppendSearchDomains is set to 1)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!SearchDomainsChanged || q->AppendSearchDomains)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // NOTE: CacheRecordRmvEventsForQuestion will not generate RMV events for queries that have non-zero
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // LOAddressAnswers. Hence it is important that we call CacheRecordRmvEventsForQuestion before
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // LocalRecordRmvEventsForQuestion (which decrements LOAddressAnswers). Let us say that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // /etc/hosts has an A Record for web.apple.com. Any queries for web.apple.com will be answered locally.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // But this can't prevent a CNAME/AAAA query to not to be sent on the wire. When it is sent on the wire,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // it could create cache entries. When we are restarting queries, we can't deliver the cache RMV events
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // for the original query using these cache entries as ADDs were never delivered using these cache
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // entries and hence this order is needed.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the query is suppressed, the RMV events won't be delivered
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!CacheRecordRmvEventsForQuestion(m, q)) { LogInfo("mDNSCoreRestartAddressQueries: Question deleted while delivering Cache Record RMV events"); continue; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // SuppressQuery status does not affect questions that are answered using local records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!LocalRecordRmvEventsForQuestion(m, q)) { LogInfo("mDNSCoreRestartAddressQueries: Question deleted while delivering Local Record RMV events"); continue; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreRestartAddressQueries: Stop question %p %##s (%s), AppendSearchDomains %d, qnameOrig %p", q,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->qname.c, DNSTypeName(q->qtype), q->AppendSearchDomains, q->qnameOrig);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Reset state so that it looks like it was in the beginning i.e it should look at /etc/hosts, cache
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and then search domains should be appended. At the beginning, qnameOrig was NULL.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreRestartAddressQueries: qnameOrig %##s", q->qnameOrig);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->RetryWithSearchDomains = ApplySearchDomainsFirst(q) ? 1 : 0;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 3. Callback before we start the query
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (BeforeStartCallback) BeforeStartCallback(m, context);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 4. Restart all the stopped queries
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreRestartAddressQueries: Start question %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void mDNSCoreRestartQueries(mDNS *const m)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Retrigger all our uDNS questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNSCoreRestartQueries: ERROR m->CurrentQuestion already set: %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!mDNSOpaque16IsZero(q->TargetQID) && ActiveQuestion(q)) ActivateUnicastQuery(m, q, mDNStrue);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Retrigger all our mDNS questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (q = m->Questions; q; q=q->next) // Scan our list of questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// restart question if it's multicast and currently active
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void mDNSCoreRestartQuestion(mDNS *const m, DNSQuestion *q)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSOpaque16IsZero(q->TargetQID) && ActiveQuestion(q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->ThisQInterval = InitialQuestionInterval; // MUST be > zero for an active question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->RequestUnicast = SET_QU_IN_FIRST_FOUR_QUERIES;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#else // mDNS_REQUEST_UNICAST_RESPONSE
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // mDNS_REQUEST_UNICAST_RESPONSE
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ExpireDupSuppressInfo(q->DupSuppress, m->timenow);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// restart the probe/announce cycle for multicast record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void mDNSCoreRestartRegistration(mDNS *const m, AuthRecord *rr, int announceCount)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType == kDNSRecordTypeVerified && !rr->DependentOn) rr->resrec.RecordType = kDNSRecordTypeUnique;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->ProbeCount = DefaultProbeCountForRecordType(rr->resrec.RecordType);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // announceCount < 0 indicates default announce count should be used
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->AnnounceCount = 0; // Do not announce keepalive records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// ***************************************************************************
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void mDNS_UpdateAllowSleep(mDNS *const m)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Don't sleep if we are a proxy for any services
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_snprintf(reason, sizeof(reason), "sleep proxy for %d records", m->ProxyRecords);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNS_UpdateAllowSleep: Sleep disabled because we are proxying %d records", m->ProxyRecords);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (allowSleep && mDNSCoreHaveAdvertisedMulticastServices(m))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Scan the list of active interfaces
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (intf->McastTxRx && !intf->Loopback && !mDNSPlatformInterfaceIsD2D(intf->InterfaceID))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Disallow sleep if this interface doesn't support NetWake
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_snprintf(reason, sizeof(reason), "%s does not support NetWake", intf->ifname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNS_UpdateAllowSleep: Sleep disabled because %s does not support NetWake", intf->ifname);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // If the interface can be an in-NIC Proxy, we should check if it can accomodate all the records
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // that will be offloaded. If not, we should prevent sleep.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // This check will be possible once the lower layers provide an API to query the space available for offloads on the NIC.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // Disallow sleep if there is no sleep proxy server
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome const CacheRecord *cr = FindSPSInCache1(m, &intf->NetWakeBrowse, mDNSNULL, mDNSNULL);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome mDNS_snprintf(reason, sizeof(reason), "No sleep proxy server on %s", intf->ifname);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogInfo("mDNS_UpdateAllowSleep: Sleep disabled because %s has no sleep proxy server", intf->ifname);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome else if (m->SPSType != 0)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome mDNSu32 metric = SPSMetric(cr->resrec.rdata->u.name.c);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome mDNS_snprintf(reason, sizeof(reason), "No sleep proxy server with better metric on %s", intf->ifname);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogInfo("mDNS_UpdateAllowSleep: Sleep disabled because %s has no sleep proxy server with a better metric", intf->ifname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Call the platform code to enable/disable sleep
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformSetAllowSleep(m, allowSleep, reason);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif /* !defined(IDLESLEEPCONTROL_DISABLED) */
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool mDNSUpdateOkToSend(mDNS *const m, AuthRecord *rr, NetworkInterfaceInfo *const intf, mDNSu32 scopeid)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If it is not a uDNS record, check to see if the updateid is zero. "updateid" is cleared when we have
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // sent the resource record on all the interfaces. If the update id is not zero, check to see if it is time
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (AuthRecord_uDNS(rr) || (rr->AuthFlags & AuthFlagsWakeOnly) || mDNSOpaque16IsZero(rr->updateid) ||
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->timenow - (rr->LastAPTime + rr->ThisAPInterval) < 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we have a pending registration for "scopeid", it is ok to send the update on that interface.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the scopeid is too big to check for validity, we don't check against updateIntID. When
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we successfully update on all the interfaces (with whatever set in "rr->updateIntID"), we clear
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // updateid and we should have returned from above.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: scopeid is the same as intf->InterfaceID. It is passed in so that we don't have to call the
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // platform function to extract the value from "intf" every time.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((scopeid >= (sizeof(rr->updateIntID) * mDNSNBBY) || bit_get_opaque64(rr->updateIntID, scopeid)) &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (!rr->resrec.InterfaceID || rr->resrec.InterfaceID == intf->InterfaceID))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void UpdateRMACCallback(mDNS *const m, void *context)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome IPAddressMACMapping *addrmap = (IPAddressMACMapping *)context ;
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogMsg("UpdateRMACCallback: Address mapping is NULL");
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // If this is a non-sleep proxy keepalive record and the remote IP address matches, update the RData
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (!rr->WakeUp.HMAC.l[0] && mDNS_KeepaliveRecord(&rr->resrec))
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // Update the MAC address only if it is not a zero MAC address
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome mDNSu8 *ptr = GetValueForMACAddr((mDNSu8 *)(addrmap->ethaddr), (mDNSu8 *) (addrmap->ethaddr + sizeof(addrmap->ethaddr)), &macAddr);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (ptr != mDNSNULL && !mDNSEthAddressIsZero(macAddr))
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome UpdateKeepaliveRData(m, rr, mDNSNULL, mDNStrue, (char *)(addrmap->ethaddr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport mStatus UpdateKeepaliveRData(mDNS *const m, AuthRecord *rr, NetworkInterfaceInfo *const intf, mDNSBool updateMac, char *ethAddr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: If we fail to update the DNS NULL record with additional information in this function, it will be registered
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // with the SPS like any other record. SPS will not send keepalives if it does not have additional information.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_ExtractKeepaliveInfo(rr, &timeout, &laddr, &raddr, ð, &seq, &ack, &lport, &rport, &win);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!timeout || mDNSAddressIsZero(&laddr) || mDNSAddressIsZero(&raddr) || mDNSIPPortIsZero(lport) ||
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("UpdateKeepaliveRData: not a valid record %s for keepalive %#a:%d %#a:%d", ARDisplayString(m, rr), &laddr, lport.NotAnInteger, &raddr, rport.NotAnInteger);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome newrdlength = mDNS_snprintf((char *)&txt.c[1], sizeof(txt.c) - 1, "t=%d i=%d c=%d h=%#a d=%#a l=%u r=%u m=%s", timeout, kKeepaliveRetryInterval, kKeepaliveRetryCount, &laddr, &raddr, mDNSVal16(lport), mDNSVal16(rport), ethAddr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome newrdlength = mDNS_snprintf((char *)&txt.c[1], sizeof(txt.c) - 1, "t=%d i=%d c=%d H=%#a D=%#a l=%u r=%u m=%s", timeout, kKeepaliveRetryInterval, kKeepaliveRetryCount, &laddr, &raddr, mDNSVal16(lport), mDNSVal16(rport), ethAddr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this keepalive packet would be sent on a different interface than the current one that we are processing
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // now, then we don't update the DNS NULL record. But we do not prevent it from registering with the SPS. When SPS sees
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // this DNS NULL record, it does not send any keepalives as it does not have all the information
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformMemZero(&mti, sizeof (mDNSTCPInfo));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ret = mDNSPlatformRetrieveTCPInfo(m, &laddr, &lport, &raddr, &rport, &mti);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNSPlatformRetrieveTCPInfo: mDNSPlatformRetrieveTCPInfo failed %d", ret);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((intf != mDNSNULL) && (mti.IntfId != intf->InterfaceID))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSPlatformRetrieveTCPInfo: InterfaceID mismatch mti.IntfId = %p InterfaceID = %p", mti.IntfId, intf->InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome newrdlength = mDNS_snprintf((char *)&txt.c[1], sizeof(txt.c) - 1, "t=%d i=%d c=%d h=%#a d=%#a l=%u r=%u m=%.6a s=%u a=%u w=%u", timeout, kKeepaliveRetryInterval, kKeepaliveRetryCount, &laddr, &raddr, mDNSVal16(lport), mDNSVal16(rport), ð, mti.seq, mti.ack, mti.window);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome newrdlength = mDNS_snprintf((char *)&txt.c[1], sizeof(txt.c) - 1, "t=%d i=%d c=%d H=%#a D=%#a l=%u r=%u m=%.6a s=%u a=%u w=%u", timeout, kKeepaliveRetryInterval, kKeepaliveRetryCount, &laddr, &raddr, mDNSVal16(lport), mDNSVal16(rport), ð, mti.seq, mti.ack, mti.window);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Did we insert a null byte at the end ?
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("UpdateKeepaliveRData: could not allocate memory %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Include the length for the null byte at the end
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Account for the first length byte and the null byte at the end
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rdsize = newrdlength > sizeof(RDataBody) ? newrdlength : sizeof(RDataBody);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome newrd = mDNSPlatformMemAllocate(sizeof(RData) - sizeof(RDataBody) + rdsize);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!newrd) { LogMsg("UpdateKeepaliveRData: ptr NULL"); return mStatus_NoMemoryErr; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformMemCopy(&newrd->u, txt.c, newrdlength);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we are updating the record for the first time, rdata points to rdatastorage as the rdata memory
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // was allocated as part of the AuthRecord itself. We allocate memory when we update the AuthRecord.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the resource record has data that we allocated in a previous pass (to update MAC address),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // free that memory here before copying in the new data.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("UpdateKeepaliveRData: Freed allocated memory for keep alive packet: %s ", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SetNewRData(&rr->resrec, newrd, newrdlength); // Update our rdata
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("UpdateKeepaliveRData: successfully updated the record %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void SendSPSRegistrationForOwner(mDNS *const m, NetworkInterfaceInfo *const intf, const mDNSOpaque16 id, const OwnerOptData *const owner)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const int optspace = DNSOpt_Header_Space + DNSOpt_LeaseData_Space + DNSOpt_Owner_Space(&m->PrimaryMAC, &intf->MAC);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome scopeid = mDNSPlatformInterfaceIndexfromInterfaceID(m, intf->InterfaceID, mDNStrue);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome intf->NextSPSAttemptTime = m->timenow + mDNSPlatformOneSecond;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->NextScheduledSPRetry - intf->NextSPSAttemptTime > 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NextScheduledSPRetry = intf->NextSPSAttemptTime;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("SendSPSRegistration: %s SPS %d (%d) %##s not yet resolved", intf->ifname, intf->NextSPSAttempt, sps, intf->NetWakeResolve[sps].qname.c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Mark our mDNS records (not unicast records) for transfer to SPS
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We may have to register this record over multiple interfaces and we don't want to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // overwrite the id. We send the registration over interface X with id "IDX" and before
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we get a response, we overwrite with id "IDY" for interface Y and we won't accept responses
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // for "IDX". Hence, we want to use the same ID across all interfaces.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // In the case of sleep proxy server transfering its records when it goes to sleep, the owner
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // option check below will set the same ID across the records from the same owner. Records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // with different owner option gets different ID.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!(rr->AuthFlags & AuthFlagsWakeOnly) && rr->resrec.RecordType > kDNSRecordTypeDeregistering)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.InterfaceID == intf->InterfaceID || (!rr->resrec.InterfaceID && (rr->ForceMCast || IsLocalDomain(rr->resrec.name))))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSPlatformMemSame(owner, &rr->WakeUp, sizeof(*owner)))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->SendRNow = mDNSInterfaceMark; // mark it now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When we are registering on the first interface, rr->updateid is zero in which case
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // initialize with the new ID. For subsequent interfaces, we want to use the same ID.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // At the end, all the updates sent across all the interfaces with the same ID.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // To comply with RFC 2782, PutResourceRecord suppresses name compression for SRV records in unicast updates.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For now we follow that same logic for SPS registrations too.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we decide to compress SRV records in SPS registrations in the future, we can achieve that by creating our
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // initial DNSMessage with h.flags set to zero, and then update it to UpdateReqFlags right before sending the packet.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome InitializeDNSMessage(&m->omsg.h, msgid, UpdateReqFlags);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->SendRNow || mDNSUpdateOkToSend(m, rr, intf, scopeid))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSPlatformMemSame(owner, &rr->WakeUp, sizeof(*owner)))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu8 *const limit = m->omsg.data + (m->omsg.h.mDNS_numUpdates ? NormalMaxDNSMessageData : AbsoluteMaxDNSMessageData) - optspace;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we can't update the keepalive record, don't send it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNS_KeepaliveRecord(&rr->resrec) && (UpdateKeepaliveRData(m, rr, intf, mDNSfalse, mDNSNULL) != mStatus_NoError))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (scopeid < (sizeof(rr->updateIntID) * mDNSNBBY))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rrclass |= kDNSClass_UniqueRRSet; // Temporarily set the 'unique' bit so PutResourceRecord will set it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome newptr = PutResourceRecordTTLWithLimit(&m->omsg, p, &m->omsg.h.mDNS_numUpdates, &rr->resrec, rr->resrec.rroriginalttl, limit);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rrclass &= ~kDNSClass_UniqueRRSet; // Make sure to clear 'unique' bit back to normal state
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("SendSPSRegistration put %s FAILED %d/%d %s", intf->ifname, p - m->omsg.data, limit - m->omsg.data, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("SendSPSRegistration put %s 0x%x 0x%x (updateid %d) %s", intf->ifname, rr->updateIntID.l[1], rr->updateIntID.l[0], mDNSVal16(m->omsg.h.id), ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // should be initialized above
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSOpaque16IsZero(rr->updateid)) LogMsg("SendSPSRegistration: ERROR!! rr %s updateid is zero", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->NextScheduledResponse - (rr->LastAPTime + rr->ThisAPInterval) >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NextScheduledResponse = (rr->LastAPTime + rr->ThisAPInterval);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetupResourceRecord(&opt, mDNSNULL, mDNSInterface_Any, kDNSType_OPT, kStandardTTL, kDNSRecordTypeKnownUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome opt.resrec.rdlength = sizeof(rdataOPT) * 2; // Two options in this OPT record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome opt.resrec.rdata->u.opt[0].opt = kDNSOpt_Lease;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome opt.resrec.rdata->u.opt[0].optlen = DNSOpt_LeaseData_Space - 4;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome opt.resrec.rdata->u.opt[0].u.updatelease = DEFAULT_UPDATE_LEASE;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SetupOwnerOpt(m, intf, &opt.resrec.rdata->u.opt[1]); // use our own interface information
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else // otherwise, use the owner data we were given
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome opt.resrec.rdata->u.opt[1].opt = kDNSOpt_Owner;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome opt.resrec.rdata->u.opt[1].optlen = DNSOpt_Owner_Space(&owner->HMAC, &owner->IMAC) - 4;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("SendSPSRegistration put %s %s", intf->ifname, ARDisplayString(m, &opt));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome p = PutResourceRecordTTLWithLimit(&m->omsg, p, &m->omsg.h.numAdditionals, &opt.resrec, opt.resrec.rroriginalttl, m->omsg.data + AbsoluteMaxDNSMessageData);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("SendSPSRegistration: Failed to put OPT record (%d updates) %s", m->omsg.h.mDNS_numUpdates, ARDisplayString(m, &opt));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("SendSPSRegistration: Sending Update %s %d (%d) id %5d with %d records %d bytes to %#a:%d", intf->ifname, intf->NextSPSAttempt, sps,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSVal16(m->omsg.h.id), m->omsg.h.mDNS_numUpdates, p - m->omsg.data, &intf->SPSAddr[sps], mDNSVal16(intf->SPSPort[sps]));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // if (intf->NextSPSAttempt < 5) m->omsg.h.flags = zeroID; // For simulating packet loss
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome err = mDNSSendDNSMessage(m, &m->omsg, p, intf->InterfaceID, mDNSNULL, &intf->SPSAddr[sps], intf->SPSPort[sps], mDNSNULL, mDNSNULL, mDNSfalse);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (err) LogSPS("SendSPSRegistration: mDNSSendDNSMessage err %d", err);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (err && intf->SPSAddr[sps].type == mDNSAddrType_IPv4 && intf->NetWakeResolve[sps].ThisQInterval == -1)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("SendSPSRegistration %d %##s failed to send to IPv4 address; will try IPv6 instead", sps, intf->NetWakeResolve[sps].qname.c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome intf->NetWakeResolve[sps].qtype = kDNSType_AAAA;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_StartQuery_internal(m, &intf->NetWakeResolve[sps]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome intf->NextSPSAttemptTime = m->timenow + mDNSPlatformOneSecond * 10; // If successful, update NextSPSAttemptTime
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSOpaque16IsZero(id) && intf->NextSPSAttempt < 8) intf->NextSPSAttempt++;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool RecordIsFirstOccurrenceOfOwner(mDNS *const m, const AuthRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (ar = m->ResourceRecords; ar && ar != rr; ar=ar->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSPlatformMemSame(&rr->WakeUp, &ar->WakeUp, sizeof(rr->WakeUp))) return mDNSfalse;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNSCoreStoreProxyRR(mDNS *const m, const mDNSInterfaceID InterfaceID, AuthRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AuthRecord *newRR = mDNSPlatformMemAllocate(sizeof(AuthRecord));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("%s : could not allocate memory for new resource record", __func__);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformMemZero(newRR, sizeof(AuthRecord));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetupResourceRecord(newRR, mDNSNULL, InterfaceID, rr->resrec.rrtype,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rroriginalttl, rr->resrec.RecordType,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName(&newRR->namestorage, &rr->namestorage);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome newRR->resrec.rdlength = DomainNameLength(rr->resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome newRR->resrec.namehash = DomainNameHashValue(newRR->resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome newRR->resrec.rdata->u.ipv4 = rr->resrec.rdata->u.ipv4;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome newRR->resrec.rdata->u.ipv6 = rr->resrec.rdata->u.ipv6;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Insert the new node at the head of the list.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("%s : Storing proxy record : %s ", __func__, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Some records are interface specific and some are not. The ones that are supposed to be registered
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// on multiple interfaces need to be initialized with all the valid interfaces on which it will be sent.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// updateIntID bit field tells us on which interfaces we need to register this record. When we get an
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// ack from the sleep proxy server, we clear the interface bit. This way, we know when a record completes
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// registration on all the interfaces
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void SPSInitRecordsBeforeUpdate(mDNS *const m, mDNSOpaque64 updateIntID, mDNSBool *WakeOnlyService)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("SPSInitRecordsBeforeUpdate: UpdateIntID 0x%x 0x%x", updateIntID.l[1], updateIntID.l[0]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Before we store the A and AAAA records that we are going to register with the sleep proxy,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // make sure that the old sleep proxy records are removed.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For records that are registered only on a specific interface, mark only that bit as it will
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // never be registered on any other interface. For others, it should be sent on all interfaces.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ar->resrec.RecordType == kDNSRecordTypeShared && ar->RequireGoodbye)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("Setting scopeid (ALL) 0x%x 0x%x for %s", updateIntID.l[1], updateIntID.l[0], ARDisplayString(m, ar));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Filter records that belong to interfaces that we won't register the records on. UpdateIntID captures
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // exactly this.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu32 scopeid = mDNSPlatformInterfaceIndexfromInterfaceID(m, ar->resrec.InterfaceID, mDNStrue);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((scopeid < (sizeof(updateIntID) * mDNSNBBY)) && bit_get_opaque64(updateIntID, scopeid))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("SPSInitRecordsBeforeUpdate: Setting scopeid(%d) 0x%x 0x%x for %s", scopeid, ar->updateIntID.l[1],
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("SPSInitRecordsBeforeUpdate: scopeid %d beyond range or not valid for SPS registration", scopeid);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Store the A and AAAA records that we registered with the sleep proxy.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We will use this to prevent spurious name conflicts that may occur when we wake up
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ar->resrec.rrtype == kDNSType_A || ar->resrec.rrtype == kDNSType_AAAA)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSCoreStoreProxyRR(m, ar->resrec.InterfaceID, ar);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void SendSPSRegistration(mDNS *const m, NetworkInterfaceInfo *const intf, const mDNSOpaque16 id)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SendSPSRegistrationForOwner(m, intf, id, &owner);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!mDNSPlatformMemSame(&owner, &ar->WakeUp, sizeof(owner)) && RecordIsFirstOccurrenceOfOwner(m, ar))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SendSPSRegistrationForOwner(m, intf, id, &owner);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// RetrySPSRegistrations is called from SendResponses, with the lock held
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void RetrySPSRegistrations(mDNS *const m)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // First make sure none of our interfaces' NextSPSAttemptTimes are inadvertently set to m->timenow + mDNSPlatformOneSecond * 10
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (intf->NextSPSAttempt && intf->NextSPSAttemptTime == m->timenow + mDNSPlatformOneSecond * 10)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Retry any record registrations that are due
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!AuthRecord_uDNS(rr) && !mDNSOpaque16IsZero(rr->updateid) && m->timenow - (rr->LastAPTime + rr->ThisAPInterval) >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we still have registrations pending on this interface, send it now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu32 scopeid = mDNSPlatformInterfaceIndexfromInterfaceID(m, intf->InterfaceID, mDNStrue);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((scopeid >= (sizeof(rr->updateIntID) * mDNSNBBY) || bit_get_opaque64(rr->updateIntID, scopeid)) &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (!rr->resrec.InterfaceID || rr->resrec.InterfaceID == intf->InterfaceID))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("RetrySPSRegistrations: 0x%x 0x%x (updateid %d) %s", rr->updateIntID.l[1], rr->updateIntID.l[0], mDNSVal16(rr->updateid), ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For interfaces where we did an SPS registration attempt, increment intf->NextSPSAttempt
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (intf->NextSPSAttempt && intf->NextSPSAttemptTime == m->timenow + mDNSPlatformOneSecond * 10 && intf->NextSPSAttempt < 8)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void NetWakeResolve(mDNS *const m, DNSQuestion *question, const ResourceRecord *const answer, QC_result AddRecord)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome NetworkInterfaceInfo *intf = (NetworkInterfaceInfo *)question->QuestionContext;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome int sps = (int)(question - intf->NetWakeResolve);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (void)m; // Unused
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("NetWakeResolve: SPS: %d Add: %d %s", sps, AddRecord, RRDisplayString(m, answer));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!AddRecord) return; // Don't care about REMOVE events
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (answer->rrtype != question->qtype) return; // Don't care about CNAMEs
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // if (answer->rrtype == kDNSType_AAAA && sps == 0) return; // To test failing to resolve sleep proxy's address
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1. Got the SRV record; now look up the target host's IP address
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome intf->SPSPort[sps] = answer->rdata->u.srv.port;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName(&question->qname, &answer->rdata->u.srv.target);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (answer->rrtype == kDNSType_A && answer->rdlength == sizeof(mDNSv4Addr))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2. Got an IPv4 address for the target host; record address and initiate an SPS registration if appropriate
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome intf->SPSAddr[sps].ip.v4 = answer->rdata->u.ipv4;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (sps == intf->NextSPSAttempt/3) SendSPSRegistration(m, intf, zeroID); // If we're ready for this result, use it now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (answer->rrtype == kDNSType_A && answer->rdlength == 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 3. Got negative response -- target host apparently has IPv6 disabled -- so try looking up the target host's IPv4 address(es) instead
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("NetWakeResolve: SPS %d %##s has no IPv4 address, will try IPv6 instead", sps, question->qname.c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (answer->rrtype == kDNSType_AAAA && answer->rdlength == sizeof(mDNSv6Addr) && mDNSv6AddressIsLinkLocal(&answer->rdata->u.ipv6))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 4. Got the target host's IPv6 link-local address; record address and initiate an SPS registration if appropriate
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome intf->SPSAddr[sps].ip.v6 = answer->rdata->u.ipv6;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (sps == intf->NextSPSAttempt/3) SendSPSRegistration(m, intf, zeroID); // If we're ready for this result, use it now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport mDNSBool mDNSCoreHaveAdvertisedMulticastServices(mDNS *const m)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNS_KeepaliveRecord(&rr->resrec) || (rr->resrec.rrtype == kDNSType_SRV && !AuthRecord_uDNS(rr) && !mDNSSameIPPort(rr->resrec.rdata->u.srv.port, DiscardPort)))
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas SoomemDNSlocal void SendGoodbyesForSelectServices(mDNS *const m, mDNSBool *servicePresent, mDNSu32 serviceType)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Mark all the records we need to deregister and send them
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // If the service type is wake only service and the auth flags match and requires a goodbye
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // OR if the service type is AC only and it is not a keepalive record,
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // mark the records we need to deregister and send them
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if ((serviceType == WAKE_ONLY_SERVICE && (rr->AuthFlags & AuthFlagsWakeOnly) &&
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome rr->resrec.RecordType == kDNSRecordTypeShared && rr->RequireGoodbye) ||
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome (serviceType == AC_ONLY_SERVICE && !mDNS_KeepaliveRecord(&rr->resrec)))
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome// This function is used only in the case of local NIC proxy. For external
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome// sleep proxy server, we do this in SPSInitRecordsBeforeUpdate when we
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome// walk the resource records.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas SoomemDNSlocal void SendGoodbyesForWakeOnlyService(mDNS *const m, mDNSBool *WakeOnlyService)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome return SendGoodbyesForSelectServices(m, WakeOnlyService, WAKE_ONLY_SERVICE);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // APPLE_OSx_mDNSResponder
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas SoomemDNSlocal void SendGoodbyesForACOnlyServices(mDNS *const m, mDNSBool *acOnlyService)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome return SendGoodbyesForSelectServices(m, acOnlyService, AC_ONLY_SERVICE);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void SendSleepGoodbyes(mDNS *const m, mDNSBool AllInterfaces, mDNSBool unicast)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If AllInterfaces is not set, the caller has already marked it appropriately
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // on which interfaces this should be sent.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SleepRecordRegistrations(m); // If we have no SPS, need to deregister our uDNS records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif /* UNICAST_DISABLED */
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Mark all the records we need to deregister and send them
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType == kDNSRecordTypeShared && rr->RequireGoodbye)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome * This function attempts to detect if multiple interfaces are on the same subnet.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome * It makes this determination based only on the IPv4 Addresses and subnet masks.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome * IPv6 link local addresses that are configured by default on all interfaces make
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome * it hard to make this determination
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome * The 'real' fix for this would be to send out multicast packets over one interface
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome * and conclude that multiple interfaces are on the same subnet only if these packets
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome * are seen on other interfaces on the same system
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool skipSameSubnetRegistration(mDNS *const m, mDNSInterfaceID *regID, mDNSu32 count, mDNSInterfaceID intfid)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (newIntf = FirstInterfaceForID(m, intfid); newIntf; newIntf = newIntf->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for ( i = 0; i < count; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = FirstInterfaceForID(m, regID[i]); intf; intf = intf->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((intf->ip.ip.v4.NotAnInteger & intf->mask.ip.v4.NotAnInteger) == (newIntf->ip.ip.v4.NotAnInteger & newIntf->mask.ip.v4.NotAnInteger))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("%s : Already registered for the same subnet (IPv4) for interface %s", __func__, intf->ifname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Loop through the keepalive records and callback with an error
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((mDNS_KeepaliveRecord(&rr->resrec)) && (rr->resrec.RecordType != kDNSRecordTypeDeregistering))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("DoKeepaliveCallbacks: Invoking the callback for %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->RecordCallback(m, rr, mStatus_BadStateErr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// BeginSleepProcessing is called, with the lock held, from either mDNS_Execute or mDNSCoreMachineSleep
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void BeginSleepProcessing(mDNS *const m)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!m->SystemWakeOnLANEnabled) LogSPS("BeginSleepProcessing: m->SystemWakeOnLANEnabled is false");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (!mDNSCoreHaveAdvertisedMulticastServices(m)) LogSPS("BeginSleepProcessing: No advertised services");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else // If we have at least one advertised service
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Clear out the SCDynamic entry that stores the external SPS information
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Intialize it to false. These values make sense only when SleepState is set to Sleeping.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If it is not multicast capable, we could not have possibly discovered sleep proxy
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!intf->McastTxRx || mDNSPlatformInterfaceIsD2D(intf->InterfaceID))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("BeginSleepProcessing: %-6s Ignoring for registrations", intf->ifname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we are not capable of WOMP, then don't register with sleep proxy.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: If we are not NetWake capable, we don't browse for the sleep proxy server.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We might find sleep proxy servers in the cache and start a resolve on them.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // But then if the interface goes away, we won't stop these questions because
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // mDNS_DeactivateNetWake_internal assumes that a browse has been started for it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to stop both the browse and resolve questions.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("BeginSleepProcessing: %-6s not capable of magic packet wakeup", intf->ifname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Check if we have already registered with a sleep proxy for this subnet
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (skipSameSubnetRegistration(m, registeredIntfIDS, registeredCount, intf->InterfaceID))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("%s : Skipping sleep proxy registration on %s", __func__, intf->ifname);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (ActivateLocalProxy(m, intf, &keepaliveOnly) == mStatus_NoError)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SendGoodbyesForWakeOnlyService(m, &WakeOnlyService);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome SendGoodbyesForACOnlyServices(m, &ACOnlyService);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("BeginSleepProcessing: %-6s using local proxy", intf->ifname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This will leave m->SleepState set to SleepState_Transferring,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // which is okay because with no outstanding resolves, or updates in flight,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // mDNSCoreReadyForSleep() will conclude correctly that all the updates have already completed
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome registeredIntfIDS[registeredCount] = intf->InterfaceID;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // APPLE_OSX_mDNSResponder
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If on battery, do not attempt to offload to external sleep proxies
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->SystemWakeOnLANEnabled == mDNS_WakeOnBattery)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("BegingSleepProcessing: Not connected to AC power - Not registering with an external sleep proxy.");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // APPLE_OSX_mDNSResponder
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!sps[0]) LogSPS("BeginSleepProcessing: %-6s %#a No Sleep Proxy Server found (Next Browse Q in %d, interval %d)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome intf->ifname, &intf->ip, NextQSendTime(&intf->NetWakeBrowse) - m->timenow, intf->NetWakeBrowse.ThisQInterval);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome intf->NextSPSAttemptTime = m->timenow + mDNSPlatformOneSecond;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome scopeid = mDNSPlatformInterfaceIndexfromInterfaceID(m, intf->InterfaceID, mDNStrue);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Now we know for sure that we have to wait for registration to complete on this interface.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (scopeid < (sizeof(updateIntID) * mDNSNBBY))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Don't need to set m->NextScheduledSPRetry here because we already set "m->NextScheduledSPRetry = m->timenow" above
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<3; i++)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogFatalError("BeginSleepProcessing: %s %d intf->SPSAddr[i].type %d", intf->ifname, i, intf->SPSAddr[i].type);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (intf->NetWakeResolve[i].ThisQInterval >= 0)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogFatalError("BeginSleepProcessing: %s %d intf->NetWakeResolve[i].ThisQInterval %d", intf->ifname, i, intf->NetWakeResolve[i].ThisQInterval);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (intf->NetWakeResolve[i].ThisQInterval >= 0) mDNS_StopQuery(m, &intf->NetWakeResolve[i]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("BeginSleepProcessing: %-6s Found Sleep Proxy Server %d TTL %d %s", intf->ifname, i, sps[i]->resrec.rroriginalttl, CRDisplayString(m, sps[i]));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetupQuestion(&intf->NetWakeResolve[i], intf->InterfaceID, &sps[i]->resrec.rdata->u.name, kDNSType_SRV, NetWakeResolve, intf);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome intf->NetWakeResolve[i].ReturnIntermed = mDNStrue;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_StartQuery_internal(m, &intf->NetWakeResolve[i]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we are registering with a Sleep Proxy for a new subnet, add it to our list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome registeredIntfIDS[registeredCount] = intf->InterfaceID;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we have at least one interface on which we are registering with an external sleep proxy,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // initialize all the records appropriately.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SPSInitRecordsBeforeUpdate(m, updateIntID, &WakeOnlyService);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Call the applicaitons that registered a keepalive record to inform them that we failed to offload
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the records to a sleep proxy.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("BeginSleepProcessing: Did not register with an in-NIC proxy - invoking the callbacks for KA records");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // SendSleepGoodbyes last two arguments control whether we send goodbyes on all
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // interfaces and also deregister unicast registrations.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // - If there are no sleep proxy servers, then send goodbyes on all interfaces
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // for both multicast and unicast.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // - If we skipped registrations on some interfaces, then we have already marked
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // them appropriately above. We don't need to send goodbyes for unicast as
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we have registered with at least one sleep proxy.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // - If we are not planning to send any goodbyes, then check for WakeOnlyServices.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: If we are planning to send goodbyes, we mark the record with mDNSInterfaceAny
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and call SendResponses which inturn calls ShouldSendGoodbyesBeforeSleep which looks
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // at WakeOnlyServices first.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("BeginSleepProcessing: Not registering with Sleep Proxy Server");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("BeginSleepProcessing: Not registering with Sleep Proxy Server on all interfaces");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we saw WakeOnly service above, send the goodbyes now.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogSPS("BeginSleepProcessing: Sending goodbyes for %s", WakeOnlyService? "WakeOnlyService" : "AC Only Service");
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Call mDNSCoreMachineSleep(m, mDNStrue) when the machine is about to go to sleep.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Call mDNSCoreMachineSleep(m, mDNSfalse) when the machine is has just woken up.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Normally, the platform support layer below mDNSCore should call this, not the client layer above.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void mDNSCoreMachineSleep(mDNS *const m, mDNSBool sleep)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("%s (old state %d) at %ld", sleep ? "Sleeping" : "Waking", m->SleepState, m->timenow);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we're going to sleep, need to stop advertising that we're a Sleep Proxy Server
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_DropLockBeforeCallback(); // mDNS_DeregisterService expects to be called without the lock held, so we emulate that here
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (oldstate == 1) mDNS_DeregisterService(m, &m->SPSRecords);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->SystemWakeOnLANEnabled && m->DelaySleep)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we just woke up moments ago, allow ten seconds for networking to stabilize before going back to sleep
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("mDNSCoreMachineSleep: Re-sleeping immediately after waking; will delay for %d ticks", m->DelaySleep - m->timenow);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->SleepLimit = NonZeroTime(m->DelaySleep + mDNSPlatformOneSecond * 10);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->SleepLimit = NonZeroTime(m->timenow + mDNSPlatformOneSecond * 10);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("mDNSCoreMachineSleep: m->SleepState %d (%s) seq %d", m->SleepState,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->SleepState == SleepState_Transferring ? "Transferring" :
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->SleepState == SleepState_Sleeping ? "Sleeping" : "?", m->SleepSeqNum);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Reset SleepLimit back to 0 now that we're awake again.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we were previously sleeping, but now we're not, increment m->SleepSeqNum to indicate that we're entering a new period of wakefulness
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSCoreBeSleepProxyServer_internal(m, m->SPSType, m->SPSPortability, m->SPSMarginalPower, m->SPSTotalPower, m->SPSFeatureFlags);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // ... and the same for NextSPSAttempt
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next)) intf->NextSPSAttempt = -1;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Restart unicast and multicast queries
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and reactivtate service registrations
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NextSRVUpdate = NonZeroTime(m->timenow + mDNSPlatformOneSecond);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreMachineSleep waking: NextSRVUpdate in %d %d", m->NextSRVUpdate - m->timenow, m->timenow);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2. Re-validate our cache records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // start time of this statistics gathering interval
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // APPLE_OSX_mDNSResponder
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Temporary fix: For unicast cache records, look at how much time we slept.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Adjust the RecvTime by the amount of time we slept so that we age the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // cache record appropriately. If it is expired already, purge. If there
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // is a network change that happens after the wakeup, we might purge the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // cache anyways and this helps only in the case where there are no network
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // changes across sleep/wakeup transition.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: If there is a network/DNS server change that already happened and
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // these cache entries are already refreshed and we are getting a delayed
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // wake up notification, we might adjust the TimeRcvd based on the time slept
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // now which can cause the cache to purge pre-maturely. As this is not a very
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // common case, this should happen rarely.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu32 uTTL = RRUnadjustedTTL(cr->resrec.rroriginalttl);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSs32 remain = uTTL - (m->timenow - cr->TimeRcvd) / mDNSPlatformOneSecond;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // -if we have slept longer than the remaining TTL, purge and start fresh.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // -if we have been sleeping for a long time, we could reduce TimeRcvd below by
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // a sufficiently big value which could cause the value to go into the future
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // because of the signed comparison of time. For this to happen, we should have been
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // sleeping really long (~24 days). For now, we want to be conservative and flush even
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // if we have slept for more than two days.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreMachineSleep: %s: Purging cache entry SleptTime %d, Remaining TTL %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome cr->TimeRcvd -= (diff * mDNSPlatformOneSecond);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->timenow - (cr->TimeRcvd + ((mDNSs32)uTTL * mDNSPlatformOneSecond)) >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreMachineSleep: %s: Purging after adjusting the remaining TTL %d by %d seconds",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreMachineSleep: %s: Adjusted the remain ttl %u by %d seconds", CRDisplayString(m, cr), remain, diff);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Reconfirm_internal(m, cr, kDefaultReconfirmTimeForWake);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 3. Retrigger probing and announcing for all our authoritative records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 4. Refresh NAT mappings
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We don't want to have to assume that all hardware can necessarily keep accurate
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // track of passage of time while asleep, so on wake we refresh our NAT mappings.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We typically wake up with no interfaces active, so there's no need to rush to try to find our external address.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // But if we do get a network configuration change, mDNSMacOSXNetworkChanged will call uDNS_SetupDNSConfig, which
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // will call mDNS_SetPrimaryInterfaceInfo, which will call RecreateNATMappings to refresh them, potentially sooner
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // than five seconds from now.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreMachineSleep: recreating NAT mappings in 5 seconds");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome RecreateNATMappings(m, mDNSPlatformOneSecond * 5);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport mDNSBool mDNSCoreReadyForSleep(mDNS *m, mDNSs32 now)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we've not hit the sleep limit time, and it's not time for our next retry, we can skip these checks
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->SleepLimit - now > 0 && m->NextScheduledSPRetry - now > 0) goto notready;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // See if we might need to retransmit any lost Sleep Proxy Registrations
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("mDNSCoreReadyForSleep: retrying for %s SPS %d try %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome intf->ifname, intf->NextSPSAttempt/3, intf->NextSPSAttempt);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Don't need to "goto notready" here, because if we do still have record registrations
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // that have not been acknowledged yet, we'll catch that in the record list scan below.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->NextScheduledSPRetry - intf->NextSPSAttemptTime > 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NextScheduledSPRetry = intf->NextSPSAttemptTime;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Scan list of interfaces, and see if we're still waiting for any sleep proxy resolves to complete
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome int sps = (intf->NextSPSAttempt == 0) ? 0 : (intf->NextSPSAttempt-1)/3;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (intf->NetWakeResolve[sps].ThisQInterval >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("mDNSCoreReadyForSleep: waiting for SPS Resolve %s %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome intf->ifname, intf->NetWakeResolve[sps].qname.c, DNSTypeName(intf->NetWakeResolve[sps].qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Scan list of registered records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = m->ResourceRecords; rr; rr = rr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome { LogSPS("mDNSCoreReadyForSleep: waiting for SPS updateIntID 0x%x 0x%x (updateid %d) %s", rr->updateIntID.l[1], rr->updateIntID.l[0], mDNSVal16(rr->updateid), ARDisplayString(m,rr)); goto spsnotready; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Scan list of private LLQs, and make sure they've all completed their handshake with the server
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!mDNSOpaque16IsZero(q->TargetQID) && q->LongLived && q->ReqLease == 0 && q->tcp)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("mDNSCoreReadyForSleep: waiting for LLQ %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Scan list of registered records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = m->ResourceRecords; rr; rr = rr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome { LogSPS("mDNSCoreReadyForSleep: waiting for Record updateIntID 0x%x 0x%x (updateid %d) %s", rr->updateIntID.l[1], rr->updateIntID.l[0], mDNSVal16(rr->updateid), ARDisplayString(m,rr)); goto notready; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!RecordReadyForSleep(m, rr)) { LogSPS("mDNSCoreReadyForSleep: waiting for %s", ARDisplayString(m, rr)); goto notready; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we failed to complete sleep proxy registration within ten seconds, we give up on that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and allow up to ten seconds more to complete wide-area deregistration instead
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("Failed to register with SPS, now sending goodbyes");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("ReadyForSleep mDNS_DeactivateNetWake %s %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome intf->ifname, intf->NetWakeResolve[0].qname.c, DNSTypeName(intf->NetWakeResolve[0].qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = m->ResourceRecords; rr; rr = rr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("ReadyForSleep clearing updateIntID 0x%x 0x%x (updateid %d) for %s", rr->updateIntID.l[1], rr->updateIntID.l[0], mDNSVal16(rr->updateid), ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We'd really like to allow up to ten seconds more here,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // but if we don't respond to the sleep notification within 30 seconds
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we'll be put back to sleep forcibly without the chance to schedule the next maintenance wake.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Right now we wait 16 sec after wake for all the interfaces to come up, then we wait up to 10 seconds
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // more for SPS resolves and record registrations to complete, which puts us at 26 seconds.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we allow just one more second to send our goodbyes, that puts us at 27 seconds.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->SleepLimit = now + mDNSPlatformOneSecond * 1;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport mDNSs32 mDNSCoreIntervalToNextWake(mDNS *const m, mDNSs32 now)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Even when we have no wake-on-LAN-capable interfaces, or we failed to find a sleep proxy, or we have other
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // failure scenarios, we still want to wake up in at most 120 minutes, to see if the network environment has changed.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // E.g. we might wake up and find no wireless network because the base station got rebooted just at that moment,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and if that happens we don't want to just give up and go back to sleep and never try again.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSs32 e = now + (120 * 60 * mDNSPlatformOneSecond); // Sleep for at most 120 minutes
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (nat = m->NATTraversals; nat; nat=nat->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (nat->Protocol && nat->ExpiryTime && nat->ExpiryTime - now > mDNSPlatformOneSecond*4)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSs32 t = nat->ExpiryTime - (nat->ExpiryTime - now) / 10; // Wake up when 90% of the way to the expiry time
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (e - t > 0) e = t;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("ComputeWakeTime: %p %s Int %5d Ext %5d Err %d Retry %5d Interval %5d Expire %5d Wake %5d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome nat, nat->Protocol == NATOp_MapTCP ? "TCP" : "UDP",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSVal16(nat->IntPort), mDNSVal16(nat->ExternalPort), nat->Result,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome nat->retryPortMap ? (nat->retryPortMap - now) / mDNSPlatformOneSecond : 0,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome nat->ExpiryTime ? (nat->ExpiryTime - now) / mDNSPlatformOneSecond : 0,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This loop checks both the time we need to renew wide-area registrations,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and the time we need to renew Sleep Proxy registrations
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (ar = m->ResourceRecords; ar; ar = ar->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ar->expire && ar->expire - now > mDNSPlatformOneSecond*4)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSs32 t = ar->expire - (ar->expire - now) / 10; // Wake up when 90% of the way to the expiry time
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (e - t > 0) e = t;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("ComputeWakeTime: %p Int %7d Next %7d Expire %7d Wake %7d %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ar, ar->ThisAPInterval / mDNSPlatformOneSecond,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (ar->LastAPTime + ar->ThisAPInterval - now) / mDNSPlatformOneSecond,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ar->expire ? (ar->expire - now) / mDNSPlatformOneSecond : 0,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (t - now) / mDNSPlatformOneSecond, ARDisplayString(m, ar));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome return(e - now);
4b22b9337f359bfd063322244f5336cc7c6ffcfars// ***************************************************************************
4b22b9337f359bfd063322244f5336cc7c6ffcfars#define MustSendRecord(RR) ((RR)->NR_AnswerTo || (RR)->NR_AdditionalTo)
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal mDNSu8 *GenerateUnicastResponse(const DNSMessage *const query, const mDNSu8 *const end,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSInterfaceID InterfaceID, mDNSBool LegacyQuery, DNSMessage *const response, AuthRecord *ResponseRecords)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu8 *const limit = response->data + sizeof(response->data);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Initialize the response fields so we can answer the questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome InitializeDNSMessage(&response->h, query->h.id, ResponseFlags);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *** 1. Write out the list of questions we are actually going to answer with this packet
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<query->h.numQuestions; i++) // For each question...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = getQuestion(query, ptr, end, InterfaceID, &q); // get the question...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr=ResponseRecords; rr; rr=rr->NextResponse) // and search our list of proposed answers
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->NR_AnswerTo == ptr) // If we're going to generate a record answering this question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome { // then put the question in the question section
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome responseptr = putQuestion(response, responseptr, limit, &q.qname, q.qtype, q.qclass);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!responseptr) { debugf("GenerateUnicastResponse: Ran out of space for questions!"); return(mDNSNULL); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome break; // break out of the ResponseRecords loop, and go on to the next question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (response->h.numQuestions == 0) { LogMsg("GenerateUnicastResponse: ERROR! Why no questions?"); return(mDNSNULL); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *** 2. Write Answers
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr=ResponseRecords; rr; rr=rr->NextResponse)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu8 *p = PutResourceRecordTTL(response, responseptr, &response->h.numAnswers, &rr->resrec,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome maxttl < rr->resrec.rroriginalttl ? maxttl : rr->resrec.rroriginalttl);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else { debugf("GenerateUnicastResponse: Ran out of space for answers!"); response->h.flags.b[0] |= kDNSFlag0_TC; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *** 3. Write Additionals
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr=ResponseRecords; rr; rr=rr->NextResponse)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu8 *p = PutResourceRecordTTL(response, responseptr, &response->h.numAdditionals, &rr->resrec,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome maxttl < rr->resrec.rroriginalttl ? maxttl : rr->resrec.rroriginalttl);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else debugf("GenerateUnicastResponse: No more space for additionals");
4b22b9337f359bfd063322244f5336cc7c6ffcfars// AuthRecord *our is our Resource Record
4b22b9337f359bfd063322244f5336cc7c6ffcfars// CacheRecord *pkt is the Resource Record from the response packet we've witnessed on the network
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Returns 0 if there is no conflict
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Returns +1 if there was a conflict and we won
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Returns -1 if there was a conflict and we lost and have to rename
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal int CompareRData(const AuthRecord *const our, const CacheRecord *const pkt)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu8 ourdata[256], *ourptr = ourdata, *ourend;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu8 pktdata[256], *pktptr = pktdata, *pktend;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!our) { LogMsg("CompareRData ERROR: our is NULL"); return(+1); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!pkt) { LogMsg("CompareRData ERROR: pkt is NULL"); return(+1); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ourend = putRData(mDNSNULL, ourdata, ourdata + sizeof(ourdata), &our->resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome pktend = putRData(mDNSNULL, pktdata, pktdata + sizeof(pktdata), &pkt->resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (ourptr < ourend && pktptr < pktend && *ourptr == *pktptr) { ourptr++; pktptr++; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ourptr >= ourend && pktptr >= pktend) return(0); // If data identical, not a conflict
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ourptr >= ourend) return(-1); // Our data ran out first; We lost
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (pktptr >= pktend) return(+1); // Packet data ran out first; We won
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (*pktptr > *ourptr) return(-1); // Our data is numerically lower; We lost
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (*pktptr < *ourptr) return(+1); // Packet data is numerically lower; We won
4b22b9337f359bfd063322244f5336cc7c6ffcfars// See if we have an authoritative record that's identical to this packet record,
4b22b9337f359bfd063322244f5336cc7c6ffcfars// whose canonical DependentOn record is the specified master record.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// The DependentOn pointer is typically used for the TXT record of service registrations
4b22b9337f359bfd063322244f5336cc7c6ffcfars// It indicates that there is no inherent conflict detection for the TXT record
4b22b9337f359bfd063322244f5336cc7c6ffcfars// -- it depends on the SRV record to resolve name conflicts
4b22b9337f359bfd063322244f5336cc7c6ffcfars// If we find any identical ResourceRecords in our authoritative list, then follow their DependentOn
4b22b9337f359bfd063322244f5336cc7c6ffcfars// pointer chain (if any) to make sure we reach the canonical DependentOn record
4b22b9337f359bfd063322244f5336cc7c6ffcfars// If the record has no DependentOn, then just return that record's pointer
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Returns NULL if we don't have any local RRs that are identical to the one from the packet
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal mDNSBool MatchDependentOn(const mDNS *const m, const CacheRecord *const pktrr, const AuthRecord *const master)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (IdenticalResourceRecord(&r1->resrec, &pktrr->resrec))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (r1 = m->DuplicateRecords; r1; r1=r1->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (IdenticalResourceRecord(&r1->resrec, &pktrr->resrec))
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Find the canonical RRSet pointer for this RR received in a packet.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// If we find any identical AuthRecord in our authoritative list, then follow its RRSet
4b22b9337f359bfd063322244f5336cc7c6ffcfars// pointers (if any) to make sure we return the canonical member of this name/type/class
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Returns NULL if we don't have any local RRs that are identical to the one from the packet
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal const AuthRecord *FindRRSet(const mDNS *const m, const CacheRecord *const pktrr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (IdenticalResourceRecord(&rr->resrec, &pktrr->resrec))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (rr->RRSet && rr != rr->RRSet) rr = rr->RRSet;
4b22b9337f359bfd063322244f5336cc7c6ffcfars// PacketRRConflict is called when we've received an RR (pktrr) which has the same name
4b22b9337f359bfd063322244f5336cc7c6ffcfars// as one of our records (our) but different rdata.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// 1. If our record is not a type that's supposed to be unique, we don't care.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// 2a. If our record is marked as dependent on some other record for conflict detection, ignore this one.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// 2b. If the packet rr exactly matches one of our other RRs, and *that* record's DependentOn pointer
4b22b9337f359bfd063322244f5336cc7c6ffcfars// points to our record, ignore this conflict (e.g. the packet record matches one of our
4b22b9337f359bfd063322244f5336cc7c6ffcfars// TXT records, and that record is marked as dependent on 'our', its SRV record).
4b22b9337f359bfd063322244f5336cc7c6ffcfars// 3. If we have some *other* RR that exactly matches the one from the packet, and that record and our record
4b22b9337f359bfd063322244f5336cc7c6ffcfars// are members of the same RRSet, then this is not a conflict.
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal mDNSBool PacketRRConflict(const mDNS *const m, const AuthRecord *const our, const CacheRecord *const pktrr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If not supposed to be unique, not a conflict
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!(our->resrec.RecordType & kDNSRecordTypeUniqueMask)) return(mDNSfalse);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If a dependent record, not a conflict
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (our->DependentOn || MatchDependentOn(m, pktrr, our)) return(mDNSfalse);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the pktrr matches a member of ourset, not a conflict
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const AuthRecord *ourset = our->RRSet ? our->RRSet : our;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const AuthRecord *pktset = FindRRSet(m, pktrr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For records we're proxying, where we don't know the full
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // relationship between the records, having any matching record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // in our AuthRecords list is sufficient evidence of non-conflict
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (our->WakeUp.HMAC.l[0] && pktset) return(mDNSfalse);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Okay, this is a conflict
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Note: ResolveSimultaneousProbe calls mDNS_Deregister_internal which can call a user callback, which may change
4b22b9337f359bfd063322244f5336cc7c6ffcfars// the record list and/or question list.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void ResolveSimultaneousProbe(mDNS *const m, const DNSMessage *const query, const mDNSu8 *const end,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu8 *ptr = LocateAuthorities(query, end);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = GetLargeResourceRecord(m, query, ptr, end, q->InterfaceID, kDNSRecordTypePacketAuth, &m->rec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!ptr) break;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative && ResourceRecordAnswersQuestion(&m->rec.r.resrec, q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome int result = (int)our->resrec.rrclass - (int)m->rec.r.resrec.rrclass;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!result) result = (int)our->resrec.rrtype - (int)m->rec.r.resrec.rrtype;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!result) result = CompareRData(our, &m->rec.r);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const char *const msg = (result < 0) ? "lost:" : (result > 0) ? "won: " : "tie: ";
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("ResolveSimultaneousProbe: %p Pkt Record: %08lX %s", q->InterfaceID, m->rec.r.resrec.rdatahash, CRDisplayString(m, &m->rec.r));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("ResolveSimultaneousProbe: %p Our Record %d %s %08lX %s", our->resrec.InterfaceID, our->ProbeCount, msg, our->resrec.rdatahash, ARDisplayString(m, our));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we lost the tie-break for simultaneous probes, we don't immediately give up, because we might be seeing stale packets on the network.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Instead we pause for one second, to give the other host (if real) a chance to establish its name, and then try probing again.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If there really is another live host out there with the same name, it will answer our probes and we'll then rename.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->SuppressProbes = NonZeroTime(m->timenow + mDNSPlatformOneSecond);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome our->ProbeCount = DefaultProbeCountForTypeUnique;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("ResolveSimultaneousProbe: %p Pkt Record: %08lX %s", q->InterfaceID, m->rec.r.resrec.rdatahash, CRDisplayString(m, &m->rec.r));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("ResolveSimultaneousProbe: %p Our Record %d ign: %08lX %s", our->resrec.InterfaceID, our->ProbeCount, our->resrec.rdatahash, ARDisplayString(m, our));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ResolveSimultaneousProbe: %##s (%s): No Update Record found", our->resrec.name->c, DNSTypeName(our->resrec.rrtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal CacheRecord *FindIdenticalRecordInCache(const mDNS *const m, const ResourceRecord *const pktrr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheGroup *cg = CacheGroupForRecord(m, slot, pktrr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu16 id1 = (pktrr->rDNSServer ? pktrr->rDNSServer->resGroupID : 0);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu16 id2 = (rr->resrec.rDNSServer ? rr->resrec.rDNSServer->resGroupID : 0);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else match = (pktrr->InterfaceID == rr->resrec.InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (match && IdenticalSameNameRecord(pktrr, &rr->resrec)) break;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void DeregisterProxyRecord(mDNS *const m, AuthRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->WakeUp.HMAC = zeroEthAddr; // Clear HMAC so that mDNS_Deregister_internal doesn't waste packets trying to wake this host
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->RequireGoodbye = mDNSfalse; // and we don't want to send goodbye for it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SetSPSProxyListChanged(m->rec.r.resrec.InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void ClearKeepaliveProxyRecords(mDNS *const m, const OwnerOptData *const owner, AuthRecord *const thelist, const mDNSInterfaceID InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("ClearIdenticalProxyRecords ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Normally, the RDATA of the keepalive record will be different each time and hence we always
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // clean up the keepalive record.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (InterfaceID == rr->resrec.InterfaceID && mDNSSameEthAddress(&owner->HMAC, &rr->WakeUp.HMAC))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("ClearKeepaliveProxyRecords: Removing %3d H-MAC %.6a I-MAC %.6a %d %d %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->ProxyRecords, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, rr->WakeUp.seq, owner->seq, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Mustn't advance m->CurrentRecord until *after* mDNS_Deregister_internal, because
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // new records could have been added to the end of the list as a result of that call.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Called from mDNSCoreReceiveUpdate when we get a sleep proxy registration request,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// to check our lists and discard any stale duplicates of this record we already have
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void ClearIdenticalProxyRecords(mDNS *const m, const OwnerOptData *const owner, AuthRecord *const thelist)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("ClearIdenticalProxyRecords ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->rec.r.resrec.InterfaceID == rr->resrec.InterfaceID && mDNSSameEthAddress(&owner->HMAC, &rr->WakeUp.HMAC))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (IdenticalResourceRecord(&rr->resrec, &m->rec.r.resrec))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("ClearIdenticalProxyRecords: Removing %3d H-MAC %.6a I-MAC %.6a %d %d %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->ProxyRecords, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, rr->WakeUp.seq, owner->seq, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Mustn't advance m->CurrentRecord until *after* mDNS_Deregister_internal, because
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // new records could have been added to the end of the list as a result of that call.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Called from ProcessQuery when we get an mDNS packet with an owner record in it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void ClearProxyRecords(mDNS *const m, const OwnerOptData *const owner, AuthRecord *const thelist)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("ClearProxyRecords ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->rec.r.resrec.InterfaceID == rr->resrec.InterfaceID && mDNSSameEthAddress(&owner->HMAC, &rr->WakeUp.HMAC))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (owner->seq != rr->WakeUp.seq || m->timenow - rr->TimeRcvd > mDNSPlatformOneSecond * 60)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->AddressProxy.type == mDNSAddrType_IPv6)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We don't do this here because we know that the host is waking up at this point, so we don't send
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Unsolicited Neighbor Advertisements -- even Neighbor Advertisements agreeing with what the host should be
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // saying itself -- because it can cause some IPv6 stacks to falsely conclude that there's an address conflict.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome #if MDNS_USE_Unsolicited_Neighbor_Advertisements
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("NDP Announcement -- Releasing traffic for H-MAC %.6a I-MAC %.6a %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m,rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SendNDP(m, NDP_Adv, NDP_Override, rr, &rr->AddressProxy.ip.v6, &rr->WakeUp.IMAC, &AllHosts_v6, &AllHosts_v6_Eth);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("ClearProxyRecords: Removing %3d AC %2d %02X H-MAC %.6a I-MAC %.6a %d %d %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->ProxyRecords, rr->AnnounceCount, rr->resrec.RecordType,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, rr->WakeUp.seq, owner->seq, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType == kDNSRecordTypeDeregistering) rr->resrec.RecordType = kDNSRecordTypeShared;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->WakeUp.HMAC = zeroEthAddr; // Clear HMAC so that mDNS_Deregister_internal doesn't waste packets trying to wake this host
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->RequireGoodbye = mDNSfalse; // and we don't want to send goodbye for it, since real host is now back and functional
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SetSPSProxyListChanged(m->rec.r.resrec.InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Mustn't advance m->CurrentRecord until *after* mDNS_Deregister_internal, because
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // new records could have been added to the end of the list as a result of that call.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
4b22b9337f359bfd063322244f5336cc7c6ffcfars// ProcessQuery examines a received query to see if we have any answers to give
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal mDNSu8 *ProcessQuery(mDNS *const m, const DNSMessage *const query, const mDNSu8 *const end,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSAddr *srcaddr, const mDNSInterfaceID InterfaceID, mDNSBool LegacyQuery, mDNSBool QueryWasMulticast,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSBool QueryWasLocalUnicast, DNSMessage *const response)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome mDNSBool FromLocalSubnet = srcaddr && mDNS_AddressIsLocalSubnet(m, InterfaceID, srcaddr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheRecord *ExpectedAnswers = mDNSNULL; // Records in our cache we expect to see updated
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // POOF_ENABLED
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome DNSQuestion *DupQuestions = mDNSNULL; // Our questions that are identical to questions in this packet
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *** 1. Look in Additional Section for an OPT record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = LocateOptRR(query, end, DNSOpt_OwnerData_ID_Space);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = GetLargeResourceRecord(m, query, ptr, end, InterfaceID, kDNSRecordTypePacketAdd, &m->rec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ptr && m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative && m->rec.r.resrec.rrtype == kDNSType_OPT)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const rdataOPT *const e = (const rdataOPT *)&m->rec.r.resrec.rdata->u.data[m->rec.r.resrec.rdlength];
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Find owner sub-option(s). We verify that the MAC is non-zero, otherwise we could inadvertently
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // delete all our own AuthRecords (which are identified by having zero MAC tags on them).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (opt = &m->rec.r.resrec.rdata->u.opt[0]; opt < e; opt++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (opt->opt == kDNSOpt_Owner && opt->u.owner.vers == 0 && opt->u.owner.HMAC.l[0])
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ClearProxyRecords(m, &opt->u.owner, m->DuplicateRecords);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ClearProxyRecords(m, &opt->u.owner, m->ResourceRecords);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Look in Authority Section for NSEC3 record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSParseNSEC3Records(m, query, end, InterfaceID, &McastNSEC3Records);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *** 2. Parse Question Section and mark potential answers
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<query->h.numQuestions; i++) // For each question...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = getQuestion(query, ptr, end, InterfaceID, &pktq); // get the question...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome InitializeAnonInfoForQuestion(m, &McastNSEC3Records, &pktq);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // The only queries that *need* a multicast response are:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // * Queries sent via multicast
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // * from port 5353
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // * that don't have the kDNSQClass_UnicastResponse bit set
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // These queries need multicast responses because other clients will:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // * suppress their own identical questions when they see these questions, and
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // * expire their cache records if they don't see the expected responses
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For other queries, we may still choose to send the occasional multicast response anyway,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to keep our neighbours caches warm, and for ongoing conflict detection.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome QuestionNeedsMulticastResponse = QueryWasMulticast && !LegacyQuery && !(pktq.qclass & kDNSQClass_UnicastResponse);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Clear the UnicastResponse flag -- don't want to confuse the rest of the code that follows later
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: We use the m->CurrentRecord mechanism here because calling ResolveSimultaneousProbe
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // can result in user callbacks which may change the record list and/or question list.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Also note: we just mark potential answer records here, without trying to build the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // "ResponseRecords" list, because we don't want to risk user callbacks deleting records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // from that list while we're in the middle of trying to build it.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("ProcessQuery ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (AnyTypeRecordAnswersQuestion(&rr->resrec, &pktq) && (QueryWasMulticast || QueryWasLocalUnicast || rr->AllowRemoteQuery))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (RRTypeAnswersQuestionType(&rr->resrec, pktq.qtype))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType == kDNSRecordTypeUnique)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ResolveSimultaneousProbe(m, query, end, &pktq, rr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // As we have verified this question to be part of the same subset,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // set the anonymous data which is needed below when walk the cache
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // records to see what answers we should be expecting. The cache records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // may cache only the nsec3RR and not the anonymous data itself.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: We should check here if this is a probe-type query, and if so, generate an immediate
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // unicast answer back to the source, because timeliness in answering probes is important.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // NR_AnswerTo pointing into query packet means "answer via immediate legacy unicast" (may *also* choose to multicast)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // NR_AnswerTo == NR_AnswerUnicast means "answer via delayed unicast" (to modern querier; may promote to multicast instead)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // NR_AnswerTo == NR_AnswerMulticast means "definitely answer via multicast" (can't downgrade to unicast later)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we're not multicasting this record because the kDNSQClass_UnicastResponse bit was set,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // but the multicast querier is not on a matching subnet (e.g. because of overlaid subnets on one link)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then we'll multicast it anyway (if we unicast, the receiver will ignore it because it has an apparently non-local source)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (QuestionNeedsMulticastResponse || (!FromLocalSubnet && QueryWasMulticast && !LegacyQuery))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We only mark this question for sending if it is at least one second since the last time we multicast it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // on this interface. If it is more than a second, or LastMCInterface is different, then we may multicast it.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This is to guard against the case where someone blasts us with queries as fast as they can.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->timenow - (rr->LastMCTime + mDNSPlatformOneSecond) >= 0 ||
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (rr->LastMCInterface != mDNSInterfaceMark && rr->LastMCInterface != InterfaceID))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (!rr->NR_AnswerTo) rr->NR_AnswerTo = LegacyQuery ? ptr : NR_AnswerUnicast;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if ((rr->resrec.RecordType & kDNSRecordTypeActiveUniqueMask) && ResourceRecordIsValidAnswer(rr))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we don't have any answers for this question, but we do own another record with the same name,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then we'll want to mark it to generate an NSEC record on this interface
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (NumAnswersForThisQuestion == 0 && NSECAnswer)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we couldn't answer this question, someone else might be able to,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // so use random delay on response to reduce collisions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (NumAnswersForThisQuestion == 0) delayresponse = mDNSPlatformOneSecond; // Divided by 50 = 20ms
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We only do the following accelerated cache expiration and duplicate question suppression processing
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // for non-truncated multicast queries with multicast responses.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For any query generating a unicast response we don't do this because we can't assume we will see the response.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For truncated queries we don't do this because a response we're expecting might be suppressed by a subsequent
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // known-answer packet, and when there's packet loss we can't safely assume we'll receive *all* known-answer packets.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (QuestionNeedsMulticastResponse && !(query->h.flags.b[0] & kDNSFlag0_TC))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheGroup *cg = CacheGroupForName(m, slot, pktq.qnamehash, &pktq.qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Make a list indicating which of our own cache records we expect to see updated as a result of this query
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: Records larger than 1K are not habitually multicast, so don't expect those to be updated
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // ENABLE_MULTI_PACKET_QUERY_SNOOPING
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (cr = cg ? cg->members : mDNSNULL; cr; cr=cr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SameNameRecordAnswersQuestion(&cr->resrec, &pktq) && cr->resrec.rdlength <= SmallRecordLimit)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!cr->NextInKAList && eap != &cr->NextInKAList)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (cr->MPUnansweredQ == 0 || m->timenow - cr->MPLastUnansweredQT >= mDNSPlatformOneSecond)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Although MPUnansweredQ is only really used for multi-packet query processing,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we increment it for both single-packet and multi-packet queries, so that it stays in sync
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // with the MPUnansweredKA value, which by necessity is incremented for both query types.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // ENABLE_MULTI_PACKET_QUERY_SNOOPING
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // POOF_ENABLED
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Check if this question is the same as any of mine.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We only do this for non-truncated queries. Right now it would be too complicated to try
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to keep track of duplicate suppression state between multiple packets, especially when we
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // can't guarantee to receive all of the Known Answer packets that go with a particular query.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For anonymous question, the duplicate suppressesion should happen if the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // question belongs in the same group. As the group is expected to be
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // small, we don't do the optimization for now.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!q->Target.type && ActiveQuestion(q) && m->timenow - q->LastQTxTime > mDNSPlatformOneSecond / 4)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!q->InterfaceID || q->InterfaceID == InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q->NextInDQList == mDNSNULL && dqp != &q->NextInDQList)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->qnamehash == pktq.qnamehash && SameDomainName(&q->qname, &pktq.qname))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *** 3. Now we can safely build the list of marked answers
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = m->ResourceRecords; rr; rr=rr->next) // Now build our list of potential answers
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->NR_AnswerTo) // If we marked the record...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AddRecordToResponseList(&nrp, rr, mDNSNULL); // ... add it to the list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *** 4. Add additional records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AddAdditionalsToResponseList(m, ResponseRecords, &nrp, InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *** 5. Parse Answer Section and cancel any records disallowed by Known-Answer list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<query->h.numAnswers; i++) // For each record in the query's answer section...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Get the record...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = GetLargeResourceRecord(m, query, ptr, end, InterfaceID, kDNSRecordTypePacketAns, &m->rec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // See if this Known-Answer suppresses any of our currently planned answers
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr=ResponseRecords; rr; rr=rr->NextResponse)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (MustSendRecord(rr) && ShouldSuppressKnownAnswer(&m->rec.r, rr))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // See if this Known-Answer suppresses any previously scheduled answers (for multi-packet KA suppression)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we're planning to send this answer on this interface, and only on this interface, then allow KA suppression
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->ImmedAnswer == InterfaceID && ShouldSuppressKnownAnswer(&m->rec.r, rr))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSSameIPv4Address(rr->v4Requester, srcaddr->ip.v4)) rr->v4Requester = zerov4Addr;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSSameIPv6Address(rr->v6Requester, srcaddr->ip.v6)) rr->v6Requester = zerov6Addr;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSIPv4AddressIsZero(rr->v4Requester) && mDNSIPv6AddressIsZero(rr->v6Requester))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("Suppressed after%4d: %s", m->timenow - rr->ImmedAnswerMarkTime, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ourcacherr = FindIdenticalRecordInCache(m, &m->rec.r.resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // See if this Known-Answer suppresses any answers we were expecting for our cache records. We do this always,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // even if the TC bit is not set (the TC bit will *not* be set in the *last* packet of a multi-packet KA list).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ourcacherr && ourcacherr->MPExpectingKA && m->timenow - ourcacherr->MPLastUnansweredQT < mDNSPlatformOneSecond)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Having built our ExpectedAnswers list from the questions in this packet, we then remove
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // any records that are suppressed by the Known Answer list in this packet.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (cr->resrec.InterfaceID == InterfaceID && IdenticalResourceRecord(&m->rec.r.resrec, &cr->resrec))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome { *eap = cr->NextInKAList; cr->NextInKAList = mDNSNULL; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // POOF_ENABLED
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // See if this Known-Answer is a surprise to us. If so, we shouldn't suppress our own query.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ResourceRecordAnswersQuestion(&m->rec.r.resrec, q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome { *dqp = q->NextInDQList; q->NextInDQList = mDNSNULL; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *** 6. Cancel any additionals that were added because of now-deleted records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr=ResponseRecords; rr; rr=rr->NextResponse)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->NR_AdditionalTo && !MustSendRecord(rr->NR_AdditionalTo))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome { rr->NR_AnswerTo = mDNSNULL; rr->NR_AdditionalTo = mDNSNULL; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *** 7. Mark the send flags on the records we plan to send
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr=ResponseRecords; rr; rr=rr->NextResponse)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSBool SendMulticastResponse = mDNSfalse; // Send modern multicast response
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSBool SendUnicastResponse = mDNSfalse; // Send modern unicast response (not legacy unicast response)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // always honor kDNSQClass_UnicastResponse in embedded environment to increase reliability
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // in high multicast packet loss environments.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If it's been one TTL/4 since we multicast this, then send a multicast response
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // for conflict detection, etc.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->timenow - (rr->LastMCTime + TicksTTL(rr)/4) >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this record was marked for modern (delayed) unicast response, then mark it as promoted to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // multicast response instead (don't want to end up ALSO setting SendUnicastResponse in the check below).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this record was marked for legacy unicast response, then we mustn't change the NR_AnswerTo value.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // !TARGET_OS_EMBEDDED
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the client insists on a multicast response, then we'd better send one
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SendMulticastResponse || SendUnicastResponse)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we're already planning to send this on another interface, just send it on all interfaces
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->ImmedAnswer && rr->ImmedAnswer != InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->ImmedAnswer = InterfaceID; // Record interface to send it on
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SendUnicastResponse) rr->ImmedUnicast = mDNStrue;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSIPv4AddressIsZero(rr->v4Requester)) rr->v4Requester = srcaddr->ip.v4;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (!mDNSSameIPv4Address(rr->v4Requester, srcaddr->ip.v4)) rr->v4Requester = onesIPv4Addr;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSIPv6AddressIsZero(rr->v6Requester)) rr->v6Requester = srcaddr->ip.v6;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (!mDNSSameIPv6Address(rr->v6Requester, srcaddr->ip.v6)) rr->v6Requester = onesIPv6Addr;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If TC flag is set, it means we should expect that additional known answers may be coming in another packet,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // so we allow roughly half a second before deciding to reply (we've observed inter-packet delays of 100-200ms on 802.11)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // else, if record is a shared one, spread responses over 100ms to avoid implosion of simultaneous responses
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // else, for a simple unique record reply, we can reply immediately; no need for delay
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (query->h.flags.b[0] & kDNSFlag0_TC) delayresponse = mDNSPlatformOneSecond * 20; // Divided by 50 = 400ms
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (rr->resrec.RecordType == kDNSRecordTypeShared) delayresponse = mDNSPlatformOneSecond; // Divided by 50 = 20ms
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (rr->NR_AdditionalTo && rr->NR_AdditionalTo->NR_AnswerTo == NR_AnswerMulticast)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Since additional records are an optimization anyway, we only ever send them on one interface at a time
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If two clients on different interfaces do queries that invoke the same optional additional answer,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then the earlier client is out of luck
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // No need to set m->NextScheduledResponse here
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We'll send these additional records when we send them, or not, as the case may be
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *** 8. If we think other machines are likely to answer these questions, set our packet suppression timer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (delayresponse && (!m->SuppressSending || (m->SuppressSending - m->timenow) < (delayresponse + 49) / 50))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("Current SuppressSending delay%5ld; require%5ld", m->SuppressSending - m->timenow, (delayresponse + 49) / 50);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Pick a random delay:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We start with the base delay chosen above (typically either 1 second or 20 seconds),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and add a random value in the range 0-5 seconds (making 1-6 seconds or 20-25 seconds).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This is an integer value, with resolution determined by the platform clock rate.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We then divide that by 50 to get the delay value in ticks. We defer the division until last
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to get better results on platforms with coarse clock granularity (e.g. ten ticks per second).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // The +49 before dividing is to ensure we round up, not down, to ensure that even
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // on platforms where the native clock rate is less than fifty ticks per second,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we still guarantee that the final calculated delay is at least one platform tick.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We want to make sure we don't ever allow the delay to be zero ticks,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // because if that happens we'll fail the Bonjour Conformance Test.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Our final computed delay is 20-120ms for normal delayed replies,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // or 400-500ms in the case of multi-packet known-answer lists.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->SuppressSending = m->timenow + (delayresponse + (mDNSs32)mDNSRandom((mDNSu32)mDNSPlatformOneSecond*5) + 49) / 50;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->SuppressSending == 0) m->SuppressSending = 1;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("Set SuppressSending to %5ld", m->SuppressSending - m->timenow);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *** 9. If query is from a legacy client, or from a new client requesting a unicast reply, then generate a unicast response too
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome responseptr = GenerateUnicastResponse(query, end, InterfaceID, LegacyQuery, response, ResponseRecords);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *** 10. Finally, clear our link chains ready for use next time
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For non-truncated queries, we can definitively say that we should expect
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to be seeing a response for any records still left in the ExpectedAnswers list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (cr->UnansweredQueries == 0 || m->timenow - cr->LastUnansweredTime >= mDNSPlatformOneSecond)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("ProcessQuery: (!TC) UAQ %lu MPQ %lu MPKA %lu %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome cr->UnansweredQueries, cr->MPUnansweredQ, cr->MPUnansweredKA, CRDisplayString(m, cr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // ENABLE_MULTI_PACKET_QUERY_SNOOPING
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we've seen multiple unanswered queries for this record,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then mark it to expire in five seconds if we don't get a response by then.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (cr->UnansweredQueries >= MaxUnansweredQueries)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Only show debugging message if this record was not about to expire anyway
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (RRExpireTime(cr) - m->timenow > 4 * mDNSPlatformOneSecond)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("ProcessQuery: (Max) UAQ %lu MPQ %lu MPKA %lu mDNS_Reconfirm() for %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome cr->UnansweredQueries, cr->MPUnansweredQ, cr->MPUnansweredKA, CRDisplayString(m, cr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // ENABLE_MULTI_PACKET_QUERY_SNOOPING
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Reconfirm_internal(m, cr, kDefaultReconfirmTimeForNoAnswer);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Make a guess, based on the multi-packet query / known answer counts, whether we think we
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // should have seen an answer for this. (We multiply MPQ by 4 and MPKA by 5, to allow for
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // possible packet loss of up to 20% of the additional KA packets.)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (cr->MPUnansweredQ * 4 > cr->MPUnansweredKA * 5 + 8)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We want to do this conservatively.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If there are so many machines on the network that they have to use multi-packet known-answer lists,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then we don't want them to all hit the network simultaneously with their final expiration queries.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // By setting the record to expire in four minutes, we achieve two things:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (a) the 90-95% final expiration queries will be less bunched together
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (b) we allow some time for us to witness enough other failed queries that we don't have to do our own
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu32 remain = (mDNSu32)(RRExpireTime(cr) - m->timenow) / 4;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (remain > 240 * (mDNSu32)mDNSPlatformOneSecond)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Only show debugging message if this record was not about to expire anyway
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (RRExpireTime(cr) - m->timenow > 4 * mDNSPlatformOneSecond)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("ProcessQuery: (MPQ) UAQ %lu MPQ %lu MPKA %lu mDNS_Reconfirm() for %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome cr->UnansweredQueries, cr->MPUnansweredQ, cr->MPUnansweredKA, CRDisplayString(m, cr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (remain <= 60 * (mDNSu32)mDNSPlatformOneSecond)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome cr->UnansweredQueries++; // Treat this as equivalent to one definite unanswered query
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome cr->MPUnansweredQ = 0; // Clear MPQ/MPKA statistics
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // ENABLE_MULTI_PACKET_QUERY_SNOOPING
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // POOF_ENABLED
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome RecordDupSuppressInfo(q->DupSuppress, m->timenow, InterfaceID, srcaddr->type);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome debugf("ProcessQuery: Recorded DSI for %##s (%s) on %p/%s", q->qname.c, DNSTypeName(q->qtype), InterfaceID,
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome srcaddr->type == mDNSAddrType_IPv4 ? "v4" : "v6");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("ProcessQuery: McastNSEC3Records not used");
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void mDNSCoreReceiveQuery(mDNS *const m, const DNSMessage *const msg, const mDNSu8 *const end,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSAddr *srcaddr, const mDNSIPPort srcport, const mDNSAddr *dstaddr, mDNSIPPort dstport,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSBool QueryWasLocalUnicast = srcaddr && dstaddr &&
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome !mDNSAddrIsDNSMulticast(dstaddr) && mDNS_AddressIsLocalSubnet(m, InterfaceID, srcaddr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!InterfaceID && dstaddr && mDNSAddrIsDNSMulticast(dstaddr))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("Ignoring Query from %#-15a:%-5d to %#-15a:%-5d on 0x%p with "
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome "%2d Question%s %2d Answer%s %2d Authorit%s %2d Additional%s %d bytes (Multicast, but no InterfaceID)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome srcaddr, mDNSVal16(srcport), dstaddr, mDNSVal16(dstport), InterfaceID,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome msg->h.numQuestions, msg->h.numQuestions == 1 ? ", " : "s,",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome msg->h.numAnswers, msg->h.numAnswers == 1 ? ", " : "s,",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome msg->h.numAuthorities, msg->h.numAuthorities == 1 ? "y, " : "ies,",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome msg->h.numAdditionals, msg->h.numAdditionals == 1 ? " " : "s", end - msg->data);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome verbosedebugf("Received Query from %#-15a:%-5d to %#-15a:%-5d on 0x%p with "
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome "%2d Question%s %2d Answer%s %2d Authorit%s %2d Additional%s %d bytes",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome srcaddr, mDNSVal16(srcport), dstaddr, mDNSVal16(dstport), InterfaceID,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome msg->h.numQuestions, msg->h.numQuestions == 1 ? ", " : "s,",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome msg->h.numAnswers, msg->h.numAnswers == 1 ? ", " : "s,",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome msg->h.numAuthorities, msg->h.numAuthorities == 1 ? "y, " : "ies,",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome msg->h.numAdditionals, msg->h.numAdditionals == 1 ? " " : "s", end - msg->data);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome responseend = ProcessQuery(m, msg, end, srcaddr, InterfaceID,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome !mDNSSameIPPort(srcport, MulticastDNSPort), mDNSAddrIsDNSMulticast(dstaddr), QueryWasLocalUnicast, &m->omsg);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (responseend) // If responseend is non-null, that means we built a unicast response packet
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("Unicast Response: %d Question%s, %d Answer%s, %d Additional%s to %#-15a:%d on %p/%ld",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->omsg.h.numQuestions, m->omsg.h.numQuestions == 1 ? "" : "s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->omsg.h.numAnswers, m->omsg.h.numAnswers == 1 ? "" : "s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->omsg.h.numAdditionals, m->omsg.h.numAdditionals == 1 ? "" : "s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome srcaddr, mDNSVal16(srcport), InterfaceID, srcaddr->type);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSSendDNSMessage(m, &m->omsg, responseend, InterfaceID, mDNSNULL, srcaddr, srcport, mDNSNULL, mDNSNULL, mDNSfalse);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool TrustedSource(const mDNS *const m, const mDNSAddr *const srcaddr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (void)m; // Unused
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSSameAddress(srcaddr, &s->addr)) return(mDNStrue);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSIPPort port; // MUST BE FIRST FIELD -- mDNSCoreReceive expects every UDPSocket_struct to begin with mDNSIPPort port
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal DNSQuestion *ExpectingUnicastResponseForQuestion(const mDNS *const m, const mDNSIPPort port, const mDNSOpaque16 id, const DNSQuestion *const question, mDNSBool tcp)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSSameIPPort(tcp ? q->tcpSrcPort : q->LocalSocket->port, port) &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// This function is called when we receive a unicast response. This could be the case of a unicast response from the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// DNS server or a response to the QU query. Hence, the cache record's InterfaceId can be both NULL or non-NULL (QU case)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal DNSQuestion *ExpectingUnicastResponseForRecord(mDNS *const m,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSAddr *const srcaddr, const mDNSBool SrcLocal, const mDNSIPPort port, const mDNSOpaque16 id, const CacheRecord *const rr, mDNSBool tcp)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!q->DuplicateOf && ResourceRecordAnswersUnicastResponse(&rr->resrec, q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("ExpectingUnicastResponseForRecord msg->h.id %d q->TargetQID %d for %s", mDNSVal16(id), mDNSVal16(q->TargetQID), CRDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // if (mDNSSameAddress(srcaddr, &q->Target)) return(mDNStrue);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // if (q->LongLived && mDNSSameAddress(srcaddr, &q->servAddr)) return(mDNStrue); Shouldn't need this now that we have LLQType checking
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // if (TrustedSource(m, srcaddr)) return(mDNStrue);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("WARNING: Ignoring suspect uDNS response for %##s (%s) [q->Target %#a:%d] from %#a:%d %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->qname.c, DNSTypeName(q->qtype), &q->Target, mDNSVal16(srcp), srcaddr, mDNSVal16(port), CRDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SrcLocal && q->ExpectUnicastResp && (mDNSu32)(m->timenow - q->ExpectUnicastResp) < (mDNSu32)(mDNSPlatformOneSecond*2))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Certain data types need more space for in-memory storage than their in-packet rdlength would imply
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Currently this applies only to rdata types containing more than one domainname,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// or types where the domainname is not the last item in the structure.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSu16 GetRDLengthMem(const ResourceRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport CacheRecord *CreateNewCacheEntry(mDNS *const m, const mDNSu32 slot, CacheGroup *cg, mDNSs32 delay, mDNSBool Add, const mDNSAddr *sourceAddress)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu16 RDLength = GetRDLengthMem(&m->rec.r.resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!m->rec.r.resrec.InterfaceID) debugf("CreateNewCacheEntry %s", CRDisplayString(m, &m->rec.r));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome //if (RDLength > InlineCacheRDSize)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // LogInfo("Rdata len %4d > InlineCacheRDSize %d %s", RDLength, InlineCacheRDSize, CRDisplayString(m, &m->rec.r));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!cg) cg = GetCacheGroup(m, slot, &m->rec.r.resrec); // If we don't have a CacheGroup for this name, make one now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (cg) rr = GetCacheRecord(m, cg, RDLength); // Make a cache record, being careful not to recycle cg
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome RData *saveptr = rr->resrec.rdata; // Save the rr->resrec.rdata pointer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *rr = m->rec.r; // Block copy the CacheRecord object
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rdata = saveptr; // Restore rr->resrec.rdata after the structure assignment
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.name = cg->name; // And set rr->resrec.name to point into our CacheGroup header
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We need to add the anonymous info before we call CacheRecordAdd so that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // if it finds a matching question with this record, it bumps up the counters like
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // CurrentAnswers etc. Otherwise, when a cache entry gets removed, CacheRecordRmv
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // will complain.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.AnonInfo = m->rec.r.resrec.AnonInfo;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this is an oversized record with external storage allocated, copy rdata to external storage
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.rdata == (RData*)&rr->smallrdatastorage && RDLength > InlineCacheRDSize)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("rr->resrec.rdata == &rr->rdatastorage but length > InlineCacheRDSize %##s", m->rec.r.resrec.name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (rr->resrec.rdata != (RData*)&rr->smallrdatastorage && RDLength <= InlineCacheRDSize)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("rr->resrec.rdata != &rr->rdatastorage but length <= InlineCacheRDSize %##s", m->rec.r.resrec.name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformMemCopy(rr->resrec.rdata, m->rec.r.resrec.rdata, sizeofRDataHeader + RDLength);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rrcache_totalused_unicast += rr->resrec.rdlength;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome BumpDNSSECStats(m, kStatsActionIncrement, kStatsTypeMemoryUsage, rr->resrec.rdlength);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *(cg->rrcache_tail) = rr; // Append this record to tail of cache slot list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome cg->rrcache_tail = &(rr->next); // Advance tail pointer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheRecordAdd(m, rr); // CacheRecordAdd calls SetNextCacheCheckTimeForRecord(m, rr); for us
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Can't use the "cg->name" if we are not adding to the cache as the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // CacheGroup may be released anytime if it is empty
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome domainname *name = mDNSPlatformMemAllocate(DomainNameLength(cg->name));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void RefreshCacheRecord(mDNS *const m, CacheRecord *rr, mDNSu32 ttl)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void GrantCacheExtensions(mDNS *const m, DNSQuestion *q, mDNSu32 lease)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheGroup *cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome //LogInfo("GrantCacheExtensions: new lease %d / %s", lease, CRDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSu32 GetEffectiveTTL(const uDNS_LLQType LLQType, mDNSu32 ttl) // TTL in seconds
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (LLQType == uDNS_LLQ_Entire) ttl = kLLQ_DefLease;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the TTL is -1 for uDNS LLQ event packet, that means "remove"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else // else not LLQ (standard uDNS response)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // The TTL is already capped to a maximum value in GetLargeResourceRecord, but just to be extra safe we
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // also do this check here to make sure we can't get overflow below when we add a quarter to the TTL
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ttl > 0x60000000UL / mDNSPlatformOneSecond) ttl = 0x60000000UL / mDNSPlatformOneSecond;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For mDNS, TTL zero means "delete this record"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For uDNS, TTL zero means: this data is true at this moment, but don't cache it.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For the sake of network efficiency, we impose a minimum effective TTL of 15 seconds.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This means that we'll do our 80, 85, 90, 95% queries at 12.00, 12.75, 13.50, 14.25 seconds
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // respectively, and then if we get no response, delete the record from the cache at 15 seconds.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This gives the server up to three seconds to respond between when we send our 80% query at 12 seconds
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and when we delete the record at 15 seconds. Allowing cache lifetimes less than 15 seconds would
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (with the current code) result in the server having even less than three seconds to respond
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // before we deleted the record and reported a "remove" event to any active questions.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Furthermore, with the current code, if we were to allow a TTL of less than 2 seconds
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then things really break (e.g. we end up making a negative cache entry).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // In the future we may want to revisit this and consider properly supporting non-cached (TTL=0) uDNS answers.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// When the response does not match the question directly, we still want to cache them sometimes. The current response is
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// in m->rec.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool IsResponseAcceptable(mDNS *const m, const CacheRecord *crlist, DNSQuestion *q, mDNSBool *nseclist)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (cr = crlist; cr != (CacheRecord*)1; cr = cr->NextInCFList)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome domainname *target = GetRRDomainNameTarget(&cr->resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When we issue a query for A record, the response might contain both a CNAME and A records. Only the CNAME would
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // match the question and we already created a cache entry in the previous pass of this loop. Now when we process
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the A record, it does not match the question because the record name here is the CNAME. Hence we try to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // match with the previous records to make it an AcceptableResponse. We have to be careful about setting the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // DNSServer value that we got in the previous pass. This can happen for other record types like SRV also.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (target && cr->resrec.rdatahash == rr->namehash && SameDomainName(target, rr->name))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("IsResponseAcceptable: Found a matching entry for %##s in the CacheFlushRecords %s", rr->name->c, CRDisplayString(m, cr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Either the question requires validation or we are validating a response with DNSSEC in which case
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we need to accept the RRSIGs also so that we can validate the response. It is also possible that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we receive NSECs for our query which does not match the qname and we need to cache in that case
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // too. nseclist is set if they have to be cached as part of the negative cache record.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSBool same = SameDomainName(&q->qname, rr->name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (same && (q->qtype == rr->rrtype || rr->rrtype == kDNSType_CNAME))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("IsResponseAcceptable: Accepting, same name and qtype %s, CR %s", DNSTypeName(q->qtype),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We cache RRSIGS if it covers the question type or NSEC. If it covers a NSEC,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // "nseclist" is set
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome RDataBody2 *const rdb = (RDataBody2 *)newcr->smallrdatastorage.data;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu16 typeCovered = swap16(rrsig->typeCovered);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note the ordering. If we are looking up the NSEC record, then the RRSIG's typeCovered
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // would match the qtype and they are cached normally as they are not used to prove the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // non-existence of any name. In that case, it is like any other normal dnssec validation
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and hence nseclist should not be set.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (same && ((typeCovered == q->qtype) || (typeCovered == kDNSType_CNAME)))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("IsResponseAcceptable: Accepting RRSIG %s matches question type %s", CRDisplayString(m, newcr),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (typeCovered == kDNSType_NSEC || typeCovered == kDNSType_NSEC3)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("IsResponseAcceptable: Accepting RRSIG %s matches %s type (nseclist = 1)", CRDisplayString(m, newcr), DNSTypeName(typeCovered));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("IsResponseAcceptable: Accepting RRSIG %s matches SOA type (nseclist = 1)", CRDisplayString(m, newcr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("IsResponseAcceptable: ERROR!! Not a unicast NSEC %s", CRDisplayString(m, newcr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("IsResponseAcceptable: Accepting NSEC %s (nseclist = 1)", CRDisplayString(m, newcr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("IsResponseAcceptable: Accepting SOA %s (nseclist = 1)", CRDisplayString(m, newcr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("IsResponseAcceptable: Accepting NSEC3 %s (nseclist = 1)", CRDisplayString(m, newcr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void FreeNSECRecords(mDNS *const m, CacheRecord *NSECRecords)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// If we received zero DNSSEC records even when the DO/EDNS0 bit was set, we need to provide this
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// information to ValidatingResponse question to indicate the DNSSEC status to the application
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNSCoreReceiveNoDNSSECAnswers(mDNS *const m, const DNSMessage *const response, const mDNSu8 *end, const mDNSAddr *dstaddr,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSIPPort dstport, const mDNSInterfaceID InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i = 0; i < response->h.numQuestions && ptr && ptr < end; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = getQuestion(response, ptr, end, InterfaceID, &pktq);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ptr && (qptr = ExpectingUnicastResponseForQuestion(m, dstport, response->h.id, &pktq, !dstaddr)) &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNSCoreReceiveNoDNSSECAnswers: ERROR!! qptr %##s (%s) Duplicate question matching response", qptr->qname.c, DNSTypeName(qptr->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Be careful to call the callback for duplicate questions first and then the original
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // question. If we called the callback on the original question, it could stop and
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // a duplicate question would become the original question.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_DropLockBeforeCallback(); // Allow client (and us) to legally make mDNS API calls
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (q = qptr->next ; q && q != m->NewQuestions; q = next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveNoDNSSECAnswers: qptr %##s (%s) Duplicate question found", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNSCoreReceiveNoDNSSECAnswers: ERROR!! qptr %##s (%s) Duplicate question not ValidatingResponse", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->QuestionCallback(m, q, mDNSNULL, QC_nodnssec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome qptr->QuestionCallback(m, qptr, mDNSNULL, QC_nodnssec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNSCoreReceiveNoUnicastAnswers(mDNS *const m, const DNSMessage *const response, const mDNSu8 *end, const mDNSAddr *dstaddr,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSIPPort dstport, const mDNSInterfaceID InterfaceID, uDNS_LLQType LLQType, mDNSu8 rcode, CacheRecord *NSECRecords)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i = 0; i < response->h.numQuestions && ptr && ptr < end; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = getQuestion(response, ptr, end, InterfaceID, &q);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ptr && (qptr = ExpectingUnicastResponseForQuestion(m, dstport, response->h.id, &q, !dstaddr)))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheGroup *cg = CacheGroupForName(m, slot, q.qnamehash, &q.qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SameNameRecordAnswersQuestion(&rr->resrec, qptr))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1. If we got a fresh answer to this query, then don't need to generate a negative entry
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2. If we already had a negative entry, keep track of it so we can resurrect it instead of creating a new one
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType == kDNSRecordTypePacketNegative) neg = rr;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When we're doing parallel unicast and multicast queries for dot-local names (for supporting Microsoft
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Active Directory sites) we don't want to waste memory making negative cache entries for all the unicast answers.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Otherwise we just fill up our cache with negative entries for just about every single multicast name we ever look up
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (since the Microsoft Active Directory server is going to assert that pretty much every single multicast name doesn't exist).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This is not only a waste of memory, but there's also the problem of those negative entries confusing us later -- e.g. we
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // suppress sending our mDNS query packet because we think we already have a valid (negative) answer to that query in our cache.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // The one exception is that we *DO* want to make a negative cache entry for "local. SOA", for the (common) case where we're
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *not* on a Microsoft Active Directory network, and there is no authoritative server for "local". Note that this is not
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // in conflict with the mDNS spec, because that spec says, "Multicast DNS Zones have no SOA record," so it's okay to cache
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // negative answers for "local. SOA" from a uDNS server, because the mDNS spec already says that such records do not exist :-)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // By suppressing negative responses, it might take longer to timeout a .local question as it might be expecting a
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // response e.g., we deliver a positive "A" response and suppress negative "AAAA" response and the upper layer may
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // be waiting longer to get the AAAA response before returning the "A" response to the application. To handle this
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // case without creating the negative cache entries, we generate a negative response and let the layer above us
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // do the appropriate thing. This negative response is also needed for appending new search domains.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!InterfaceID && q.qtype != kDNSType_SOA && IsLocalDomain(&q.qname))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveNoUnicastAnswers: Generate negative response for %##s (%s)", q.qname.c, DNSTypeName(q.qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We are not creating a cache record in this case, we need to pass back
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the error we got so that the proxy code can return the right one to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the application
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveNoUnicastAnswers: Skipping check and not creating a negative cache entry for %##s (%s)", q.qname.c, DNSTypeName(q.qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We start off assuming a negative caching TTL of 60 seconds
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // but then look to see if we can find an SOA authority record to tell us a better value we should be using
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Special case for our special Microsoft Active Directory "local SOA" check.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Some cheap home gateways don't include an SOA record in the authority section when
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // they send negative responses, so we don't know how long to cache the negative result.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Because we don't want to keep hitting the root name servers with our query to find
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // if we're on a network using Microsoft Active Directory using "local" as a private
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // internal top-level domain, we make sure to cache the negative result for at least one day.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q.qtype == kDNSType_SOA && SameDomainName(&q.qname, &localdomain)) negttl = 60 * 60 * 24;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we're going to make (or update) a negative entry, then look for the appropriate TTL from the SOA record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (response->h.numAuthorities && (ptr = LocateAuthorities(response, end)) != mDNSNULL)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = GetLargeResourceRecord(m, response, ptr, end, InterfaceID, kDNSRecordTypePacketAuth, &m->rec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ptr && m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative && m->rec.r.resrec.rrtype == kDNSType_SOA)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu32 s = HashSlot(m->rec.r.resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheGroup *cgSOA = CacheGroupForRecord(m, s, &m->rec.r.resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const rdataSOA *const soa = (const rdataSOA *)m->rec.r.resrec.rdata->u.data;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We use the lesser of the SOA.MIN field and the SOA record's TTL, *except*
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // for the SOA record for ".", where the record is reported as non-cacheable
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (TTL zero) for some reason, so in this case we just take the SOA record's TTL as-is
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ttl_s > m->rec.r.resrec.rroriginalttl && m->rec.r.resrec.name->c[0])
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Create the SOA record as we may have to return this to the questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // that we are acting as a proxy for currently or in the future.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SOARecord = CreateNewCacheEntry(m, s, cgSOA, 1, mDNSfalse, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Special check for SOA queries: If we queried for a.b.c.d.com, and got no answer,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // with an Authority Section SOA record for d.com, then this is a hint that the authority
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // is d.com, and consequently SOA records b.c.d.com and c.d.com don't exist either.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // To do this we set the repeat count so the while loop below will make a series of negative cache entries for us
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For ProxyQuestions, we don't do this as we need to create additional SOA records to cache them
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // along with the negative cache record. For simplicity, we don't create the additional records.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!qptr->ProxyQuestion && q.qtype == kDNSType_SOA)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome int scount = CountLabels(m->rec.r.resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SameDomainName(SkipLeadingLabels(&q.qname, qcount - scount), m->rec.r.resrec.name))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we already had a negative entry in the cache, then we double our existing negative TTL. This is to avoid
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the case where the record doesn't exist (e.g. particularly for things like our lb._dns-sd._udp.<domain> query),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and the server returns no SOA record (or an SOA record with a small MIN TTL) so we assume a TTL
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // of 60 seconds, and we end up polling the server every minute for a record that doesn't exist.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // With this fix in place, when this happens, we double the effective TTL each time (up to one hour),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // so that we back off our polling rate and don't keep hitting the server continually.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome negttl = GetEffectiveTTL(LLQType, negttl); // Add 25% grace period if necessary
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we already had a negative cache entry just update it, else make one or more new negative cache entries.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveNoUnicastAnswers: Renewing negative TTL from %d to %d %s", neg->resrec.rroriginalttl, negttl, CRDisplayString(m, neg));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When we created the cache for the first time and answered the question, the question's
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // interval was set to MaxQuestionInterval. If the cache is about to expire and we are resending
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the queries, the interval should still be at MaxQuestionInterval. If the query is being
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // restarted (setting it to InitialQuestionInterval) for other reasons e.g., wakeup,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we should reset its question interval here to MaxQuestionInterval.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Update the NSEC records again.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // TBD: Need to purge and revalidate if the cached NSECS and the new set are not same.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!AddNSECSForCacheRecord(m, NSECRecords, neg, rcode))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We might just have an SOA record for zones that are not signed and hence don't log
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // this as an error
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveNoUnicastAnswers: AddNSECSForCacheRecord failed to add NSEC for negcr %s during refresh", CRDisplayString(m, neg));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else while (1)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNSCoreReceiveNoUnicastAnswers making negative cache entry TTL %d for %##s (%s)", negttl, name->c, DNSTypeName(q.qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome MakeNegativeCacheRecord(m, &m->rec.r, name, hash, q.qtype, q.qclass, negttl, mDNSInterface_Any, qptr->qDNSServer);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We create SOA records above which might create new cache groups. Earlier
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // in the function we looked up the cache group for the name and it could have
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // been NULL. If we pass NULL cg to new cache entries that we create below,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // it will create additional cache groups for the same name. To avoid that,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // look up the cache group again to re-initialize cg again.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Create the cache entry with delay and then add the NSEC records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to it and add it immediately.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome negcr = CreateNewCacheEntry(m, slot, cg, 1, mDNStrue, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!AddNSECSForCacheRecord(m, NSECRecords, negcr, rcode))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveNoUnicastAnswers: AddNSECSForCacheRecord failed to add NSEC for negcr %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveNoUnicastAnswers: AddNSECSForCacheRecord added neg NSEC for %s", CRDisplayString(m, negcr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Need to add with a delay so that we can tag the SOA record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome negcr = CreateNewCacheEntry(m, slot, cg, 1, mDNStrue, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome name = (const domainname *)(name->c + 1 + name->c[0]);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // For now, we don't need to update cg here, because we'll do it again immediately, back up at the start of this loop
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome //cg = CacheGroupForName(m, slot, hash, name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (NSECRecords) { LogInfo("mDNSCoreReceiveNoUnicastAnswers: NSECRecords not used"); FreeNSECRecords(m, NSECRecords); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SOARecord) { LogInfo("mDNSCoreReceiveNoUnicastAnswers: SOARecord not used"); ReleaseCacheRecord(m, SOARecord); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNSCorePrintStoredProxyRecords(mDNS *const m)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rrPtr = m->SPSRRSet; rrPtr; rrPtr = rrPtr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool mDNSCoreRegisteredProxyRecord(mDNS *const m, AuthRecord *rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rrPtr = m->SPSRRSet; rrPtr; rrPtr = rrPtr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (IdenticalResourceRecord(&rrPtr->resrec, &rr->resrec))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("mDNSCoreRegisteredProxyRecord: Ignoring packet registered with sleep proxy : %s ", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal CacheRecord* mDNSCoreReceiveCacheCheck(mDNS *const m, const DNSMessage *const response, uDNS_LLQType LLQType,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu32 slot, CacheGroup *cg, DNSQuestion *unicastQuestion, CacheRecord ***cfp, CacheRecord **NSECCachePtr,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Resource record received via unicast, the resGroupID should match ?
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu16 id1 = (rr->resrec.rDNSServer ? rr->resrec.rDNSServer->resGroupID : 0);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu16 id2 = (m->rec.r.resrec.rDNSServer ? m->rec.r.resrec.rDNSServer->resGroupID : 0);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome match = (rr->resrec.InterfaceID == InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we found this exact resource record, refresh its TTL
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (match && IdenticalSameNameRecord(&m->rec.r.resrec, &rr->resrec))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->rec.r.resrec.rdlength > InlineCacheRDSize)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome verbosedebugf("mDNSCoreReceiveCacheCheck: Found record size %5d interface %p already in cache: %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rec.r.resrec.rdlength, InterfaceID, CRDisplayString(m, &m->rec.r));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->rec.r.resrec.RecordType & kDNSRecordTypePacketUniqueMask)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this packet record has the kDNSClass_UniqueRRSet flag set, then add it to our cache flushing list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->NextInCFList == mDNSNULL && *cfp != &rr->NextInCFList && LLQType != uDNS_LLQ_Events)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this packet record is marked unique, and our previous cached copy was not, then fix it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!(rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ResourceRecordAnswersQuestion(&rr->resrec, q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.RecordType = m->rec.r.resrec.RecordType;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!SameRDataBody(&m->rec.r.resrec, &rr->resrec.rdata->u, SameDomainNameCS))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the rdata of the packet record differs in name capitalization from the record in our cache
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then mDNSPlatformMemSame will detect this. In this case, throw the old record away, so that clients get
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // a 'remove' event for the record with the old capitalization, and then an 'add' event for the new one.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // <rdar://problem/4015377> mDNS -F returns the same domain multiple times with different casing
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveCacheCheck: Discarding due to domainname case change old: %s", CRDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveCacheCheck: Discarding due to domainname case change new: %s", CRDisplayString(m, &m->rec.r));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveCacheCheck: Discarding due to domainname case change in %d slot %3d in %d %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome NextCacheCheckEvent(rr) - m->timenow, slot, m->rrcache_nextcheck[slot] - m->timenow, m->NextCacheCheck - m->timenow);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // DO NOT break out here -- we want to continue as if we never found it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (!IdenticalAnonInfo(m->rec.r.resrec.AnonInfo, rr->resrec.AnonInfo))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the NSEC3 record changed, a few possibilities
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1) the peer reinitialized e.g., after network change and still part of the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // same set.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2) the peer went to a different set but we did not see the goodbyes. If we just
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // update the nsec3 record, it would be incorrect. Flush the cache so that we
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // can deliver a RMV followed by ADD.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 3) if the peer is ourselves and we see the goodbye when moving to a different set
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and so we flush the cache and create a new cache record with the new set information.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Now we move back to the original set. In this case, we can't just update the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // NSEC3 record alone. We need to flush so that we can deliver an RMV followed by ADD
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // when we create the new cache entry.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: For case (1), we could avoid flushing the cache but we can't tell the difference
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // from the other cases.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveCacheCheck: AnonInfo changed for %s", CRDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // DO NOT break out here -- we want to continue as if we never found it. When we return
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // from this function, we will create a new cache entry with the new NSEC3 record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.rroriginalttl == 0) debugf("uDNS rescuing %s", CRDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome RefreshCacheRecord(m, rr, m->rec.r.resrec.rroriginalttl);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we may have NSEC records returned with the answer (which we don't know yet as it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // has not been processed), we need to cache them along with the first cache
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // record in the list that answers the question so that it can be used for validation
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // later. The "type" check below is to make sure that we cache on the cache record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // that would answer the question. It is possible that we might cache additional things
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // e.g., MX question might cache A records also, and we want to cache the NSEC on
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the record that answers the question.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (response->h.numAnswers && unicastQuestion && unicastQuestion->qtype == rr->resrec.rrtype
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveCacheCheck: rescuing RR %s", CRDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We have to reset the question interval to MaxQuestionInterval so that we don't keep
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // polling the network once we get a valid response back. For the first time when a new
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // cache entry is created, AnswerCurrentQuestionWithResourceRecord does that.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Subsequently, if we reissue questions from within the mDNSResponder e.g., DNS server
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // configuration changed, without flushing the cache, we reset the question interval here.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Currently, we do this for for both multicast and unicast questions as long as the record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // type is unique. For unicast, resource record is always unique and for multicast it is
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // true for records like A etc. but not for PTR.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ActiveQuestion(q) && ResourceRecordAnswersQuestion(&rr->resrec, q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNSCoreReceiveCacheCheck: Set MaxQuestionInterval for %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome break; // Why break here? Aren't there other questions we might want to look at?-- SC July 2010
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the packet TTL is zero, that means we're deleting this record.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // To give other hosts on the network a chance to protest, we push the deletion
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // out one second into the future. Also, we set UnansweredQueries to MaxUnansweredQueries.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Otherwise, we'll do final queries for this record at 80% and 90% of its apparent
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // lifetime (800ms and 900ms from now) which is a pointless waste of network bandwidth.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If record's current expiry time is more than a second from now, we set it to expire in one second.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the record is already going to expire in less than one second anyway, we leave it alone --
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we don't want to let the goodbye packet *extend* the record's lifetime in our cache.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (RRExpireTime(rr) - m->timenow > mDNSPlatformOneSecond)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNSParseNSEC3Records(mDNS *const m, const DNSMessage *const response, const mDNSu8 *end,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSInterfaceID InterfaceID, CacheRecord **NSEC3Records)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSParseNSEC3Records: ERROR can't locate authorities");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i = 0; i < response->h.numAuthorities && ptr && ptr < end; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = GetLargeResourceRecord(m, response, ptr, end, InterfaceID, kDNSRecordTypePacketAuth, &m->rec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!ptr || m->rec.r.resrec.RecordType == kDNSRecordTypePacketNegative || m->rec.r.resrec.rrtype != kDNSType_NSEC3)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNSParseNSEC3Records: ptr %p, Record %s, ignoring", ptr, CRDisplayString(m, &m->rec.r));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome cg = CacheGroupForRecord(m, slot, &m->rec.r.resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Create the cache entry but don't add it to the cache it. We need
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to cache this along with the main cache record.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr = CreateNewCacheEntry(m, slot, cg, 0, mDNSfalse, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNSParseNSEC3Records: %s", CRDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNSCoreResetRecord(mDNS *const m)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Note: mDNSCoreReceiveResponse calls mDNS_Deregister_internal which can call a user callback, which may change
4b22b9337f359bfd063322244f5336cc7c6ffcfars// the record list and/or question list.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// InterfaceID non-NULL tells us the interface this multicast response was received on
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// InterfaceID NULL tells us this was a unicast response
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// dstaddr NULL tells us we received this over an outgoing TCP connection we made
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const DNSMessage *const response, const mDNSu8 *end,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSAddr *srcaddr, const mDNSIPPort srcport, const mDNSAddr *dstaddr, mDNSIPPort dstport,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSBool ResponseMCast = dstaddr && mDNSAddrIsDNSMulticast(dstaddr);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome mDNSBool ResponseSrcLocal = !srcaddr || mDNS_AddressIsLocalSubnet(m, InterfaceID, srcaddr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome uDNS_LLQType LLQType = uDNS_recvLLQResponse(m, response, end, srcaddr, srcport, &llqMatch);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // "(CacheRecord*)1" is a special (non-zero) end-of-list marker
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We use this non-zero marker so that records in our CacheFlushRecords list will always have NextInCFList
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // set non-zero, and that tells GetCacheEntity() that they're not, at this moment, eligible for recycling.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheRecord *CacheFlushRecords = (CacheRecord*)1;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome NetworkInterfaceInfo *llintf = FirstIPv4LLInterfaceForID(m, InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // All records in a DNS response packet are treated as equally valid statements of truth. If we want
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to guard against spoof responses, then the only credible protection against that is cryptographic
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // security, e.g. DNSSEC., not worrying about which section in the spoof packet contained the record.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome int firstadditional = firstauthority + response->h.numAuthorities;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome int totalrecords = firstadditional + response->h.numAdditionals;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("Received Response from %#-15a addressed to %#-15a on %p with "
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome "%2d Question%s %2d Answer%s %2d Authorit%s %2d Additional%s %d bytes LLQType %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome response->h.numQuestions, response->h.numQuestions == 1 ? ", " : "s,",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome response->h.numAnswers, response->h.numAnswers == 1 ? ", " : "s,",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome response->h.numAuthorities, response->h.numAuthorities == 1 ? "y, " : "ies,",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome response->h.numAdditionals, response->h.numAdditionals == 1 ? " " : "s", end - response->data, LLQType);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // According to RFC 2181 <http://www.ietf.org/rfc/rfc2181.txt>
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When a DNS client receives a reply with TC
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // set, it should ignore that response, and query again, using a
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // mechanism, such as a TCP connection, that will permit larger replies.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // It feels wrong to be throwing away data after the network went to all the trouble of delivering it to us, but
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // delivering some records of the RRSet first and then the remainder a couple of milliseconds later was causing
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // failures in our Microsoft Active Directory client, which expects to get the entire set of answers at once.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // <rdar://problem/6690034> Can't bind to Active Directory
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // In addition, if the client immediately canceled its query after getting the initial partial response, then we'll
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // abort our TCP connection, and not complete the operation, and end up with an incomplete RRSet in our cache.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Next time there's a query for this RRSet we'll see answers in our cache, and assume we have the whole RRSet already,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and not even do the TCP query.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Accordingly, if we get a uDNS reply with kDNSFlag0_TC set, we bail out and wait for the TCP response containing the entire RRSet.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!InterfaceID && (response->h.flags.b[0] & kDNSFlag0_TC)) return;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1. We ignore questions (if any) in mDNS response packets
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2. If this is an LLQ response, we handle it much the same
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 3. If we get a uDNS UDP response with the TC (truncated) bit set, then we can't treat this
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // answer as being the authoritative complete RRSet, and respond by deleting all other
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // matching cache records that don't appear in this packet.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Otherwise, this is a authoritative uDNS answer, so arrange for any stale records to be purged
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ResponseMCast || LLQType == uDNS_LLQ_Events || (response->h.flags.b[0] & kDNSFlag0_TC))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Otherwise, for one-shot queries, any answers in our cache that are not also contained
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // in this response packet are immediately deemed to be invalid.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rcode = (mDNSu8)(response->h.flags.b[1] & kDNSFlag1_RC_Mask);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome failure = !(rcode == kDNSFlag1_RC_NoErr || rcode == kDNSFlag1_RC_NXDomain || rcode == kDNSFlag1_RC_NotAuth);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We could possibly combine this with the similar loop at the end of this function --
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // instead of tagging cache records here and then rescuing them if we find them in the answer section,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we could instead use the "m->PktNum" mechanism to tag each cache record with the packet number in
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // which it was received (or refreshed), and then at the end if we find any cache records which
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // answer questions in this packet's question section, but which aren't tagged with this packet's
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // packet number, then we deduce they are old and delete them
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i = 0; i < response->h.numQuestions && ptr && ptr < end; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = getQuestion(response, ptr, end, InterfaceID, &q);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ptr && (qptr = ExpectingUnicastResponseForQuestion(m, dstport, response->h.id, &q, !dstaddr)))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Remember the unicast question that we found, which we use to make caching
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // decisions later on in this function
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheGroup *cg = CacheGroupForName(m, slot, q.qnamehash, &q.qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveResponse: Setting aware for %##s (%s) on %#a", qptr->qname.c,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome DNSTypeName(qptr->qtype), &qptr->qDNSServer->addr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SameNameRecordAnswersQuestion(&rr->resrec, qptr))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("uDNS marking %p %##s (%s) %p %s", q.InterfaceID, q.qname.c, DNSTypeName(q.qtype),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.InterfaceID, CRDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Don't want to disturb rroriginalttl here, because code below might need it for the exponential backoff doubling algorithm
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (unicastQuestion && DNSSECQuestion(unicastQuestion))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveResponse: CRDNSSECQuestion set for record %s, question %##s (%s)", CRDisplayString(m, rr),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome unicastQuestion->qname.c, DNSTypeName(unicastQuestion->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we recv any error from the DNSServer for a DNSSEC Query and if we know that the server
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // is not DNSSEC aware, stop doing DNSSEC for that DNSServer. Note that by setting the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // req_DO to false here, the next retransmission for this question will turn off validation
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and hence retransmit without the EDNS0/DOK option.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (DNSSECOptionalQuestion(qptr) && qptr->qDNSServer && !qptr->qDNSServer->DNSSECAware)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveResponse: Server %p responded with code %d to DNSSEC Query %##s (%s), clear DO flag",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome qptr->qDNSServer, rcode, q.qname.c, DNSTypeName(q.qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For Unicast DNS Queries, penalize the DNSServer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveResponse: Server %p responded with code %d to query %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome qptr->qDNSServer, rcode, q.qname.c, DNSTypeName(q.qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("Ignoring %2d Answer%s %2d Authorit%s %2d Additional%s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome response->h.numAnswers, response->h.numAnswers == 1 ? ", " : "s,",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome response->h.numAuthorities, response->h.numAuthorities == 1 ? "y, " : "ies,",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome response->h.numAdditionals, response->h.numAdditionals == 1 ? "" : "s");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // not goto exit because we won't have any CacheFlushRecords and we do not want to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // generate negative cache entries (we want to query the next server)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (unicastQuestion && DNSSECQuestion(unicastQuestion))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome BumpDNSSECStats(m, kStatsActionSet, kStatsTypeMsgSize, (end - response->data));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Parse the NSEC3 records from the Authority section before we process
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the Answer section so that we can cache them along with the proper
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // cache records we create.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSParseNSEC3Records(m, response, end, InterfaceID, &McastNSEC3Records);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i = 0; i < totalrecords && ptr && ptr < end; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // All responses sent via LL multicast are acceptable for caching
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // All responses received over our outbound TCP connections are acceptable for caching
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSBool AcceptableResponse = ResponseMCast || !dstaddr || LLQType;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (Note that just because we are willing to cache something, that doesn't necessarily make it a trustworthy answer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to any specific question -- any code reading records from the cache needs to make that determination for itself.)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (i < firstauthority ) ? (mDNSu8)kDNSRecordTypePacketAns :
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (i < firstadditional) ? (mDNSu8)kDNSRecordTypePacketAuth : (mDNSu8)kDNSRecordTypePacketAdd;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = GetLargeResourceRecord(m, response, ptr, end, InterfaceID, RecordType, &m->rec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!ptr) goto exit; // Break out of the loop and clean up our CacheFlushRecords list before exiting
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->rec.r.resrec.RecordType == kDNSRecordTypePacketNegative)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We have already parsed the NSEC3 records and cached them approrpriately for
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // multicast responses.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSOpaque16IsZero(response->h.id) && m->rec.r.resrec.rrtype == kDNSType_NSEC3)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Don't want to cache OPT or TSIG pseudo-RRs
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const rdataOPT *const e = (const rdataOPT *)&m->rec.r.resrec.rdata->u.data[m->rec.r.resrec.rdlength];
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Find owner sub-option(s). We verify that the MAC is non-zero, otherwise we could inadvertently
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // delete all our own AuthRecords (which are identified by having zero MAC tags on them).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (opt = &m->rec.r.resrec.rdata->u.opt[0]; opt < e; opt++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (opt->opt == kDNSOpt_Owner && opt->u.owner.vers == 0 && opt->u.owner.HMAC.l[0])
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ClearProxyRecords(m, &opt->u.owner, m->DuplicateRecords);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ClearProxyRecords(m, &opt->u.owner, m->ResourceRecords);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // if a CNAME record points to itself, then don't add it to the cache
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((m->rec.r.resrec.rrtype == kDNSType_CNAME) && SameDomainName(m->rec.r.resrec.name, &m->rec.r.resrec.rdata->u.name))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveResponse: CNAME loop domain name %##s", m->rec.r.resrec.name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When we receive uDNS LLQ responses, we assume a long cache lifetime --
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // In the case of active LLQs, we'll get remove events when the records actually do go away
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // In the case of polling LLQs, we assume the record remains valid until the next poll
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rec.r.resrec.rroriginalttl = GetEffectiveTTL(LLQType, m->rec.r.resrec.rroriginalttl);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If response was not sent via LL multicast,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then see if it answers a recent query of ours, which would also make it acceptable for caching.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For Long Lived queries that are both sent over UDP and Private TCP, LLQType is set.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Even though it is AcceptableResponse, we need a matching DNSServer pointer for the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // queries to get ADD/RMV events. To lookup the question, we can't use
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // ExpectingUnicastResponseForRecord as the port numbers don't match. uDNS_recvLLQRespose
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // has already matched the question using the 64 bit Id in the packet and we use that here.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (llqMatch != mDNSNULL) m->rec.r.resrec.rDNSServer = uDNSServer = llqMatch->qDNSServer;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this is a DNSSEC question that is also LongLived, don't accept records from the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Additional/Authority section blindly. We need to go through IsAcceptableResponse below
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // so that NSEC/NSEC3 record are cached in the nseclist if we accept them. This can happen
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // for both negative responses and wildcard expanded positive responses as both of come
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // back with NSEC/NSEC3s.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (unicastQuestion && DNSSECQuestion(unicastQuestion))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For responses that come over TCP (Responses that can't fit within UDP) or TLS (Private queries
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // that are not long lived e.g., AAAA lookup in a Private domain), it is indicated by !dstaddr.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Even though it is AcceptableResponse, we still need a DNSServer pointer for the resource records that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we create.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome DNSQuestion *q = ExpectingUnicastResponseForRecord(m, srcaddr, ResponseSrcLocal, dstport, response->h.id, &m->rec.r, !dstaddr);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // Initialize the DNS server on the resource record which will now filter what questions we answer with
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // this record.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // We could potentially lookup the DNS server based on the source address, but that may not work always
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // and that's why ExpectingUnicastResponseForRecord does not try to verify whether the response came
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // from the DNS server that queried. We follow the same logic here. If we can find a matching quetion based
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // on the "id" and "source port", then this response answers the question and assume the response
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // came from the same DNS server that we sent the query to.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome debugf("mDNSCoreReceiveResponse: InterfaceID %p %##s (%s)", q->InterfaceID, q->qname.c, DNSTypeName(q->qtype));
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome m->rec.r.resrec.rDNSServer = uDNSServer = q->qDNSServer;
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogInfo("mDNSCoreReceiveResponse: InterfaceID %p %##s (%s)", q->InterfaceID, q->qname.c, DNSTypeName(q->qtype));
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // If we can't find a matching question, we need to see whether we have seen records earlier that matched
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // the question. The code below does that. So, make this record unacceptable for now
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome debugf("mDNSCoreReceiveResponse: Can't find question for record name %##s", m->rec.r.resrec.name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (llintf && llintf->IgnoreIPv4LL && m->rec.r.resrec.rrtype == kDNSType_A)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // There are some routers (rare, thankfully) that generate bogus ARP responses for
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // any IPv4 address they don’t recognize, including RFC 3927 IPv4 link-local addresses.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // To work with these broken routers, client devices need to blacklist these broken
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // routers and ignore their bogus ARP responses. Some devices implement a technique
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // such as the one described in US Patent 7436783, which lets clients detect and
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // ignore these broken routers: <https://www.google.com/patents/US7436783>
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // OS X and iOS do not implement this defensive mechanism, instead taking a simpler
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // approach of just detecting these broken routers and completely disabling IPv4
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // link-local communication on interfaces where a broken router is detected.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // OS X and iOS set the IFEF_ARPLL interface flag on interfaces
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // that are deemed “safe” for IPv4 link-local communication;
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // the flag is cleared on interfaces where a broken router is detected.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // OS X and iOS will not even try to communicate with an IPv4
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // link-local destination on an interface without the IFEF_ARPLL flag set.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // This can cause some badly written applications to freeze for a long time if they
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // attempt to connect to an IPv4 link-local destination address and then wait for
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // that connection attempt to time out before trying other candidate addresses.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // To mask this client bug, we suppress acceptance of IPv4 link-local address
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // records on interfaces where we know the OS will be unwilling even to attempt
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // communication with those IPv4 link-local destination addresses.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // <rdar://problem/9400639> kSuppress IPv4LL answers on interfaces without IFEF_ARPLL
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome const RDataBody2 *const rdb = (RDataBody2 *)rr->smallrdatastorage.data;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSResponder: Dropping LinkLocal packet %s", CRDisplayString(m, &m->rec.r));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1. Check that this packet resource record does not conflict with any of ours
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSOpaque16IsZero(response->h.id) && m->rec.r.resrec.rrtype != kDNSType_NSEC)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNSCoreReceiveResponse ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We accept all multicast responses, and unicast responses resulting from queries we issued
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For other unicast responses, this code accepts them only for responses with an
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (apparently) local source address that pertain to a record of our own that's in probing state
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!AcceptableResponse && !(ResponseSrcLocal && rr->resrec.RecordType == kDNSRecordTypeUnique)) continue;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (PacketRRMatchesSignature(&m->rec.r, rr)) // If interface, name, type (if shared record) and class match...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // ... check to see if type and rdata are identical
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (IdenticalSameNameRecord(&m->rec.r.resrec, &rr->resrec))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the RR in the packet is identical to ours, just check they're not trying to lower the TTL on us
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->rec.r.resrec.rroriginalttl >= rr->resrec.rroriginalttl/2 || m->SleepState)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we were planning to send on this -- and only this -- interface, then we don't need to any more
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->ImmedAnswer == InterfaceID) { rr->ImmedAnswer = mDNSNULL; rr->ImmedUnicast = mDNSfalse; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->ImmedAnswer == mDNSNULL) { rr->ImmedAnswer = InterfaceID; m->NextScheduledResponse = m->timenow; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (rr->ImmedAnswer != InterfaceID) { rr->ImmedAnswer = mDNSInterfaceMark; m->NextScheduledResponse = m->timenow; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // else, the packet RR has different type or different rdata -- check to see if this is a conflict
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (m->rec.r.resrec.rroriginalttl > 0 && PacketRRConflict(m, rr, &m->rec.r))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveResponse: Pkt Record: %08lX %s", m->rec.r.resrec.rdatahash, CRDisplayString(m, &m->rec.r));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveResponse: Our Record: %08lX %s", rr->resrec.rdatahash, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this record is marked DependentOn another record for conflict detection purposes,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then *that* record has to be bumped back to probing state to resolve the conflict
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveResponse: Dep Record: %08lX %s", rr->resrec.rdatahash, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we've just whacked this record's ProbeCount, don't need to do it again
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->ProbeCount > DefaultProbeCountForTypeUnique)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveResponse: Already reset to Probing: %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (rr->ProbeCount == DefaultProbeCountForTypeUnique)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogInfo("mDNSCoreReceiveResponse: Ignoring response received before we even began probing: %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNSCoreReceiveResponse: Received from %#a:%d %s", srcaddr, mDNSVal16(srcport), CRDisplayString(m, &m->rec.r));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we'd previously verified this record, put it back to probing state and try again
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType == kDNSRecordTypeVerified)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNSCoreReceiveResponse: Resetting to Probing: %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We set ProbeCount to one more than the usual value so we know we've already touched this record.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This is because our single probe for "example-name.local" could yield a response with (say) two A records and
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // three AAAA records in it, and we don't want to call RecordProbeFailure() five times and count that as five conflicts.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This special value is recognised and reset to DefaultProbeCountForTypeUnique in SendQueries().
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->ProbeCount = DefaultProbeCountForTypeUnique + 1;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome RecordProbeFailure(m, rr); // Repeated late conflicts also cause us to back off to the slower probing rate
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we're probing for this record, we just failed
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (rr->resrec.RecordType == kDNSRecordTypeUnique)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Before we call deregister, check if this is a packet we registered with the sleep proxy.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNSCoreReceiveResponse: ProbeCount %d; will deregister %s", rr->ProbeCount, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Deregister_internal(m, rr, mDNS_Dereg_conflict);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We assumed this record must be unique, but we were wrong. (e.g. There are two mDNSResponders on the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // same machine giving different answers for the reverse mapping record, or there are two machines on the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // network using the same IP address.) This is simply a misconfiguration, and there's nothing we can do
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to fix it -- e.g. it's not our job to be trying to change the machine's IP address. We just discard our
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // record to avoid continued conflicts (as we do for a conflict on our Unique records) and get on with life.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (rr->resrec.RecordType == kDNSRecordTypeKnownUnique)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNSCoreReceiveResponse: Unexpected conflict discarding %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Deregister_internal(m, rr, mDNS_Dereg_conflict);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNSCoreReceiveResponse: Unexpected record type %X %s", rr->resrec.RecordType, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Else, matching signature, different type or rdata, but not a considered a conflict.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the packet record has the cache-flush bit set, then we check to see if we
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // have any record(s) of the same type that we should re-assert to rescue them
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (see note about "multi-homing and bridged networks" at the end of this function).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (m->rec.r.resrec.rrtype == rr->resrec.rrtype)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((m->rec.r.resrec.RecordType & kDNSRecordTypePacketUniqueMask) && m->timenow - rr->LastMCTime > mDNSPlatformOneSecond/2)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome { rr->ImmedAnswer = mDNSInterfaceMark; m->NextScheduledResponse = m->timenow; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AcceptableResponse = IsResponseAcceptable(m, CacheFlushRecords, unicastQuestion, &nseclist);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (AcceptableResponse) m->rec.r.resrec.rDNSServer = uDNSServer;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2. See if we want to add this packet resource record to our cache
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We only try to cache answers if we have a cache to put them in
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Also, we ignore any apparent attempts at cache poisoning unicast to us that do not answer any outstanding active query
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!AcceptableResponse) LogInfo("mDNSCoreReceiveResponse ignoring %s", CRDisplayString(m, &m->rec.r));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu32 slot = HashSlot(m->rec.r.resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheGroup *cg = CacheGroupForRecord(m, slot, &m->rec.r.resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome InitializeAnonInfoForCR(m, &McastNSEC3Records, &m->rec.r);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2a. Check if this packet resource record is already in our cache.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this record should go in the nseclist, don't look in the cache for updating it.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // They are supposed to be cached under the "nsec" field of the cache record for
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // validation. Just create the cache record.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr = mDNSCoreReceiveCacheCheck(m, response, LLQType, slot, cg, unicastQuestion, &cfp, &NSECCachePtr, InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If packet resource record not in our cache, add it now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (unless it is just a deletion of a record we never had, in which case we don't care)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSBool AddToCFList = (m->rec.r.resrec.RecordType & kDNSRecordTypePacketUniqueMask) && (LLQType != uDNS_LLQ_Events);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome delay = NonZeroTime(m->timenow + mDNSPlatformOneSecond);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome delay = CheckForSoonToExpireRecords(m, m->rec.r.resrec.name, m->rec.r.resrec.namehash, slot, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If unique, assume we may have to delay delivery of this 'add' event.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Below, where we walk the CacheFlushRecords list, we either call CacheRecordDeferredAdd()
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to immediately to generate answer callbacks, or we call ScheduleNextCacheCheckTime()
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to schedule an mDNS_Execute task at the appropriate time.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr = CreateNewCacheEntry(m, slot, cg, delay, !nseclist, srcaddr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we are not creating signatures, then we need to inform DNSSEC so that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // it does not wait forever. Don't do this if we got NSEC records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // as it indicates that this name does not exist.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.rrtype == kDNSType_RRSIG && !nseclist)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Remember whether we created a cache record in response to a DNSSEC question.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This helps DNSSEC code not to reissue the question to fetch the DNSSEC records.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (unicastQuestion && DNSSECQuestion(unicastQuestion))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveResponse: CRDNSSECQuestion set for new record %s, question %##s (%s)", CRDisplayString(m, rr),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome unicastQuestion->qname.c, DNSTypeName(unicastQuestion->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // NSEC/NSEC3 records and its signatures are cached with the negative cache entry
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // which we should be creating below. It is also needed in the wildcard
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // expanded answer case and in that case it is cached along with the answer.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ScheduleNextCacheCheckTime(m, slot, rr->DelayDelivery);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr && rr->resrec.AnonInfo && m->rec.r.resrec.AnonInfo)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we've just received one or more records with their cache flush bits set,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then scan that cache slot to see if there are any old stale records we need to flush
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu32 slot = HashSlot(r1->resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const CacheGroup *cg = CacheGroupForRecord(m, slot, &r1->resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheFlushRecords = CacheFlushRecords->NextInCFList;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Look for records in the cache with the same signature as this new one with the cache flush
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // bit set, and either (a) if they're fresh, just make sure the whole RRSet has the same TTL
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (as required by DNS semantics) or (b) if they're old, mark them for deletion in one second.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We make these TTL adjustments *only* for records that still have *more* than one second
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // remaining to live. Otherwise, a record that we tagged for deletion half a second ago
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (and now has half a second remaining) could inadvertently get its life extended, by either
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (a) if we got an explicit goodbye packet half a second ago, the record would be considered
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // "fresh" and would be incorrectly resurrected back to the same TTL as the rest of the RRSet,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // or (b) otherwise, the record would not be fully resurrected, but would be reset to expire
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // in one second, thereby inadvertently delaying its actual expiration, instead of hastening it.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this were to happen repeatedly, the record's expiration could be deferred indefinitely.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // To avoid this, we need to ensure that the cache flushing operation will only act to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *decrease* a record's remaining lifetime, never *increase* it.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (r2 = cg ? cg->members : mDNSNULL; r2; r2=r2->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome id1 = (r1->resrec.rDNSServer ? r1->resrec.rDNSServer->resGroupID : 0);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome id2 = (r2->resrec.rDNSServer ? r2->resrec.rDNSServer->resGroupID : 0);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When we receive new RRSIGs e.g., for DNSKEY record, we should not flush the old
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // RRSIGS e.g., for TXT record. To do so, we need to look at the typeCovered field of
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the new RRSIG that we received. Process only if the typeCovered matches.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((r1->resrec.rrtype == r2->resrec.rrtype) && (r1->resrec.rrtype == kDNSType_RRSIG))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rdataRRSig *rrsig1 = (rdataRRSig *)(((RDataBody2 *)(r1->resrec.rdata->u.data))->data);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rdataRRSig *rrsig2 = (rdataRRSig *)(((RDataBody2 *)(r2->resrec.rdata->u.data))->data);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (swap16(rrsig1->typeCovered) != swap16(rrsig2->typeCovered))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNSCoreReceiveResponse: Received RRSIG typeCovered %s, found %s, not processing",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome DNSTypeName(swap16(rrsig1->typeCovered)), DNSTypeName(swap16(rrsig2->typeCovered)));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For Unicast (null InterfaceID) the resolver IDs should also match
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((r1->resrec.InterfaceID == r2->resrec.InterfaceID) &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If record is recent, just ensure the whole RRSet has the same TTL (as required by DNS semantics)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // else, if record is old, mark it to be flushed
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->timenow - r2->TimeRcvd < mDNSPlatformOneSecond && RRExpireTime(r2) - m->timenow > mDNSPlatformOneSecond)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we find mismatched TTLs in an RRSet, correct them.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We only do this for records with a TTL of 2 or higher. It's possible to have a
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // goodbye announcement with the cache flush bit set (or a case-change on record rdata,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // which we treat as a goodbye followed by an addition) and in that case it would be
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // inappropriate to synchronize all the other records to a TTL of 0 (or 1).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We suppress the message for the specific case of correcting from 240 to 60 for type TXT,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // because certain early Bonjour devices are known to have this specific mismatch, and
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // there's no point filling syslog with messages about something we already know about.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We also don't log this for uDNS responses, since a caching name server is obliged
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to give us an aged TTL to correct for how long it has held the record,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // so our received TTLs are expected to vary in that case
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // We also suppress log message in the case of SRV records that are recieved
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // with a TTL of 4500 that are already cached with a TTL of 120 seconds, since
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // this behavior was observed for a number of discoveryd based AppleTV's in iOS 8
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // GM builds.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (r2->resrec.rroriginalttl != r1->resrec.rroriginalttl && r1->resrec.rroriginalttl > 1)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!(r2->resrec.rroriginalttl == 240 && r1->resrec.rroriginalttl == 60 && r2->resrec.rrtype == kDNSType_TXT) &&
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome !(r2->resrec.rroriginalttl == 120 && r1->resrec.rroriginalttl == 4500 && r2->resrec.rrtype == kDNSType_SRV) &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("Correcting TTL from %4d to %4d for %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome r2->resrec.rroriginalttl, r1->resrec.rroriginalttl, CRDisplayString(m, r2));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome r2->resrec.rroriginalttl = r1->resrec.rroriginalttl;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else // else, if record is old, mark it to be flushed
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome verbosedebugf("Cache flush new %p age %d expire in %d %s", r1, m->timenow - r1->TimeRcvd, RRExpireTime(r1) - m->timenow, CRDisplayString(m, r1));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome verbosedebugf("Cache flush old %p age %d expire in %d %s", r2, m->timenow - r2->TimeRcvd, RRExpireTime(r2) - m->timenow, CRDisplayString(m, r2));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We set stale records to expire in one second.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This gives the owner a chance to rescue it if necessary.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This is important in the case of multi-homing and bridged networks:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Suppose host X is on Ethernet. X then connects to an AirPort base station, which happens to be
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // bridged onto the same Ethernet. When X announces its AirPort IP address with the cache-flush bit
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // set, the AirPort packet will be bridged onto the Ethernet, and all other hosts on the Ethernet
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // will promptly delete their cached copies of the (still valid) Ethernet IP address record.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // By delaying the deletion by one second, we give X a change to notice that this bridging has
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // happened, and re-announce its Ethernet IP address to rescue it from deletion from all our caches.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We set UnansweredQueries to MaxUnansweredQueries to avoid expensive and unnecessary
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // final expiration queries for this record.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If a record is deleted twice, first with an explicit DE record, then a second time by virtue of the cache
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // flush bit on the new record replacing it, then we allow the record to be deleted immediately, without the usual
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // one-second grace period. This improves responsiveness for mDNS_Update(), as used for things like iChat status updates.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // <rdar://problem/5636422> Updating TXT records is too slow
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We check for "rroriginalttl == 1" because we want to include records tagged by the "packet TTL is zero" check above,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // which sets rroriginalttl to 1, but not records tagged by the rdata case-change check, which sets rroriginalttl to 0.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (r2->TimeRcvd == m->timenow && r2->resrec.rroriginalttl == 1 && r2->UnansweredQueries == MaxUnansweredQueries)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("Cache flush for DE record %s", CRDisplayString(m, r2));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (RRExpireTime(r2) - m->timenow > mDNSPlatformOneSecond)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We only set a record to expire in one second if it currently has *more* than a second to live
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If it's already due to expire in a second or less, we just leave it alone
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We use (m->timenow - 1) instead of m->timenow, because we use that to identify records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // that we marked for deletion via an explicit DE record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (r1->DelayDelivery) // If we were planning to delay delivery of this record, see if we still need to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we had a unicast question for this response with at least one positive answer and we
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // have NSECRecords, it is most likely a wildcard expanded answer. Cache the NSEC and its
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // signatures along with the cache record which will be used for validation later. If
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we rescued a few records earlier in this function, then NSECCachePtr would be set. In that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // use that instead.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (response->h.numAnswers && unicastQuestion && NSECRecords)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveResponse: Updating NSECCachePtr to %s", CRDisplayString(m, r1));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: We need to do this before we call CacheRecordDeferredAdd as this
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // might start the verification process which needs these NSEC records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!AddNSECSForCacheRecord(m, NSECRecords, NSECCachePtr, rcode))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveResponse: AddNSECSForCacheRecord failed to add NSEC for %s", CRDisplayString(m, NSECCachePtr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome r1->DelayDelivery = CheckForSoonToExpireRecords(m, r1->resrec.name, r1->resrec.namehash, slot, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If no longer delaying, deliver answer now, else schedule delivery for the appropriate time
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!r1->DelayDelivery) CacheRecordDeferredAdd(m, r1);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else ScheduleNextCacheCheckTime(m, slot, r1->DelayDelivery);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we have not consumed the NSEC records yet e.g., just refreshing the cache,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // update them now for future validations.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceieveResponse: Updating NSEC records in %s", CRDisplayString(m, NSECCachePtr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!AddNSECSForCacheRecord(m, NSECRecords, NSECCachePtr, rcode))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNSCoreReceiveResponse: AddNSECSForCacheRecord failed to add NSEC for %s", CRDisplayString(m, NSECCachePtr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If there is at least one answer and we did not create RRSIGs and there was a
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // ValidatingResponse question waiting for this response, give a hint that no RRSIGs
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // were created. We don't need to give a hint:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // - if we have no answers, the mDNSCoreReceiveNoUnicastAnswers below should
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // generate a negative response
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // - if we have NSECRecords, it means we might have a potential proof for
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // non-existence of name that we are looking for
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (response->h.numAnswers && !rrsigsCreated && DNSSECQuestion && !NSECRecords)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSCoreReceiveNoDNSSECAnswers(m, response, end, dstaddr, dstport, InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // See if we need to generate negative cache entries for unanswered unicast questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSCoreReceiveNoUnicastAnswers(m, response, end, dstaddr, dstport, InterfaceID, LLQType, rcode, NSECRecords);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNSCoreReceiveResponse: McastNSEC3Records not used");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// ScheduleWakeup causes all proxy records with WakeUp.HMAC matching mDNSEthAddr 'e' to be deregistered, causing
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// multiple wakeup magic packets to be sent if appropriate, and all records to be ultimately freed after a few seconds.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// ScheduleWakeup is called on mDNS record conflicts, ARP conflicts, NDP conflicts, or reception of trigger traffic
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// that warrants waking the sleeping host.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// ScheduleWakeup must be called with the lock held (ScheduleWakeupForList uses mDNS_Deregister_internal)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void ScheduleWakeupForList(mDNS *const m, mDNSInterfaceID InterfaceID, mDNSEthAddr *e, AuthRecord *const thelist)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We need to use the m->CurrentRecord mechanism here when dealing with DuplicateRecords list as
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // mDNS_Deregister_internal deregisters duplicate records immediately as they are not used
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to send wakeups or goodbyes. See the comment in that function for more details. To keep it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // simple, we use the same mechanism for both lists.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!e->l[0])
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("ScheduleWakeupForList ERROR: Target HMAC is zero");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.InterfaceID == InterfaceID && rr->resrec.RecordType != kDNSRecordTypeDeregistering && mDNSSameEthAddress(&rr->WakeUp.HMAC, e))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ScheduleWakeupForList: Scheduling wakeup packets for %s", ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void ScheduleWakeup(mDNS *const m, mDNSInterfaceID InterfaceID, mDNSEthAddr *e)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!e->l[0]) { LogMsg("ScheduleWakeup ERROR: Target HMAC is zero"); return; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ScheduleWakeupForList(m, InterfaceID, e, m->DuplicateRecords);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ScheduleWakeupForList(m, InterfaceID, e, m->ResourceRecords);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void SPSRecordCallback(mDNS *const m, AuthRecord *const ar, mStatus result)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("SPS Callback %d %s", result, ARDisplayString(m, ar));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("%-7s Conflicting mDNS -- waking %.6a %s", InterfaceNameForID(m, ar->resrec.InterfaceID), &ar->WakeUp.HMAC, ARDisplayString(m, ar));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SendWakeup(m, ar->resrec.InterfaceID, &ar->WakeUp.IMAC, &ar->WakeUp.password); // Send one wakeup magic packet
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ScheduleWakeup(m, ar->resrec.InterfaceID, &ar->WakeUp.HMAC); // Schedule all other records with the same owner to be woken
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (result == mStatus_NameConflict || result == mStatus_MemFree)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSu8 *GetValueForMACAddr(mDNSu8 *ptr, mDNSu8 *limit, mDNSEthAddr *eth)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome mDNSu16 val = 0; /* need to use 16 bit int to detect overflow */
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i = 0; ptr < limit && *ptr != ' ' && i < 17; i++, ptr++)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogMsg("GetValueForMACAddr: Address malformed colons %d val %d", colons, val);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("GetValueForMACAddr: Address malformed colons %d", colons);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSu8 *GetValueForIPv6Addr(mDNSu8 *ptr, mDNSu8 *limit, mDNSv6Addr *v6)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // RFC 3513: Section 2.2 specifies IPv6 presentation format. The following parsing
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // handles both (1) and (2) and does not handle embedded IPv4 addresses.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // First forms a address in "v6addr", then expands to fill the zeroes in and returns
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the result in "v6"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome numColons = numBytes = value = digitsProcessed = zeroFillStart = 0;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we have already seen a "::", we should not see one more. Handle the special
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // case of "::"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // if we never filled any bytes and the next character is space (we have reached the end)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we are done
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!numBytes && (ptr + 1) < limit && *(ptr + 1) == ' ')
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("GetValueForIPv6Addr: zeroFillStart non-zero %d", zeroFillStart);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We processed "::". We need to fill zeroes later. For now, mark the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // point where we will start filling zeroes from.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if ((ptr + 1) < limit && *(ptr + 1) == ' ')
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We have a trailing ":" i.e., no more characters after ":"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For a fully expanded IPv6 address, we fill the 14th and 15th byte outside of this while
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // loop below as there is no ":" at the end. Hence, the last two bytes that can possibly
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // filled here is 12 and 13.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (numBytes > 13) { LogMsg("GetValueForIPv6Addr:1: numBytes is %d", numBytes); return mDNSNULL; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome v6addr[numBytes++] = (mDNSu8) ((value >> 8) & 0xFF);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Make sure that we did not fill the 13th and 14th byte above
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (numBytes > 14) { LogMsg("GetValueForIPv6Addr:2: numBytes is %d", numBytes); return mDNSNULL; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We should be processing the last set of bytes following the last ":" here
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("GetValueForIPv6Addr: no trailing bytes after colon, numBytes is %d", numBytes);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (numBytes > 14) { LogMsg("GetValueForIPv6Addr:3: numBytes is %d", numBytes); return mDNSNULL; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome v6addr[numBytes++] = (mDNSu8) ((value >> 8) & 0xFF);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome int i, j, n;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i = 0; i < zeroFillStart; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (j = i, n = 0; n < 16 - numBytes; j++, n++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (; j < 16; i++, j++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("GetValueForIPv6addr: Not enough bytes for IPv6 address, numBytes is %d", numBytes);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSu8 *GetValueForIPv4Addr(mDNSu8 *ptr, mDNSu8 *limit, mDNSv4Addr *v4)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogMsg("GetValueForIPv4Addr: something wrong ptr(%p) %c, limit %p, dots %d", ptr, *ptr, limit, dots);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We have a zero at the end and if we reached that, then we are done.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (*ptr == 0 && ptr == limit - 1 && dots == 3)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else { LogMsg("GetValueForIPv4Addr: something wrong ptr(%p) %c, limit %p, dots %d", ptr, *ptr, limit, dots); return mDNSNULL; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (dots != 3) { LogMsg("GetValueForIPv4Addr: Address malformed dots %d", dots); return mDNSNULL; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSu8 *GetValueForKeepalive(mDNSu8 *ptr, mDNSu8 *limit, mDNSu32 *value)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We have a zero at the end and if we reached that, then we are done.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else { LogMsg("GetValueForKeepalive: *ptr %d, ptr %p, limit %p, ptr +1 %d", *ptr, ptr, limit, *(ptr + 1)); return mDNSNULL; }
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas SoomemDNSexport mDNSBool mDNSValidKeepAliveRecord(AuthRecord *rr)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome mDNS_ExtractKeepaliveInfo(rr, &timeout, &laddr, &raddr, ð, &seq, &ack, &lport, &rport, &win);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (mDNSAddressIsZero(&laddr) || mDNSIPPortIsZero(lport) ||
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome mDNSAddressIsZero(&raddr) || mDNSIPPortIsZero(rport) ||
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNS_ExtractKeepaliveInfo(AuthRecord *ar, mDNSu32 *timeout, mDNSAddr *laddr, mDNSAddr *raddr, mDNSEthAddr *eth, mDNSu32 *seq,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu32 *ack, mDNSIPPort *lport, mDNSIPPort *rport, mDNSu16 *win)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu8 *limit = ptr + len - 1; // Exclude the first byte that is the length
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = GetValueForIPv4Addr(ptr, limit, &laddr->ip.v4);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = GetValueForIPv4Addr(ptr, limit, &raddr->ip.v4);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = GetValueForIPv6Addr(ptr, limit, &laddr->ip.v6);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = GetValueForIPv6Addr(ptr, limit, &raddr->ip.v6);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = GetValueForKeepalive(ptr, limit, &value);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!ptr) { LogMsg("mDNS_ExtractKeepaliveInfo: Cannot parse\n"); return; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Extract everything in network order so that it is easy for sending a keepalive and also
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // for matching incoming TCP packets
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome //if (*timeout < 120) *timeout = 120;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_ExtractKeepaliveInfo: unknown value %c\n", param);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Matches the proxied auth records to the incoming TCP packet and returns the match and its sequence and ack in "rseq" and "rack" so that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// the clients need not retrieve this information from the auth record again.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal AuthRecord* mDNS_MatchKeepaliveInfo(mDNS *const m, const mDNSAddr* pladdr, const mDNSAddr* praddr, const mDNSIPPort plport,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSIPPort prport, mDNSu32 *rseq, mDNSu32 *rack)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_ExtractKeepaliveInfo(ar, &timeout, &laddr, &raddr, ð, &seq, &ack, &lport, &rport, &win);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Did we parse correctly ?
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!timeout || mDNSAddressIsZero(&laddr) || mDNSAddressIsZero(&raddr) || !seq || !ack || mDNSIPPortIsZero(lport) || mDNSIPPortIsZero(rport) || !win)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_MatchKeepaliveInfo: not a valid record %s for keepalive", ARDisplayString(m, ar));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_MatchKeepaliveInfo: laddr %#a pladdr %#a, raddr %#a praddr %#a, lport %d plport %d, rport %d prport %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome &laddr, pladdr, &raddr, praddr, mDNSVal16(lport), mDNSVal16(plport), mDNSVal16(rport), mDNSVal16(prport));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Does it match the incoming TCP packet ?
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSSameAddress(&laddr, pladdr) && mDNSSameAddress(&raddr, praddr) && mDNSSameIPPort(lport, plport) && mDNSSameIPPort(rport, prport))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // returning in network order
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNS_SendKeepalives(mDNS *const m)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_ExtractKeepaliveInfo(ar, &timeout, &laddr, &raddr, ð, &seq, &ack, &lport, &rport, &win);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!timeout || mDNSAddressIsZero(&laddr) || mDNSAddressIsZero(&raddr) || !seq || !ack || mDNSIPPortIsZero(lport) || mDNSIPPortIsZero(rport) || !win)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_SendKeepalives: not a valid record %s for keepalive", ARDisplayString(m, ar));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_SendKeepalives: laddr %#a raddr %#a lport %d rport %d", &laddr, &raddr, mDNSVal16(lport), mDNSVal16(rport));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When we receive a proxy update, we set KATimeExpire to zero so that we always send a keepalive
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // immediately (to detect any potential problems). After that we always set it to a non-zero value.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!ar->KATimeExpire || (m->timenow - ar->KATimeExpire >= 0))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformSendKeepalive(&laddr, &raddr, &lport, &rport, seq, ack, win);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ar->KATimeExpire = NonZeroTime(m->timenow + timeout * mDNSPlatformOneSecond);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNS_SendKeepaliveACK(mDNS *const m, AuthRecord *ar)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogInfo("mDNS_SendKeepalivesACK: AuthRecord is NULL");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_ExtractKeepaliveInfo(ar, &timeout, &laddr, &raddr, ð, &seq, &ack, &lport, &rport, &win);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!timeout || mDNSAddressIsZero(&laddr) || mDNSAddressIsZero(&raddr) || !seq || !ack || mDNSIPPortIsZero(lport) || mDNSIPPortIsZero(rport) || !win)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNS_SendKeepaliveACK: not a valid record %s for keepalive", ARDisplayString(m, ar));
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // To send a keepalive ACK, we need to add one to the sequence number from the keepalive
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // record, which is the TCP connection's "next" sequence number minus one. Otherwise, the
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // keepalive ACK also ends up being a keepalive probe. Also, seq is in network byte order, so
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // it's converted to host byte order before incrementing it by one.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome seqInc = (mDNSu32)((ptr[0] << 24) | (ptr[1] << 16) | (ptr[2] << 8) | ptr[3]) + 1;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_SendKeepaliveACK: laddr %#a raddr %#a lport %d rport %d", &laddr, &raddr, mDNSVal16(lport), mDNSVal16(rport));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformSendKeepalive(&laddr, &raddr, &lport, &rport, seq, ack, win);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNSCoreReceiveUpdate(mDNS *const m,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const DNSMessage *const msg, const mDNSu8 *end,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSAddr *srcaddr, const mDNSIPPort srcport, const mDNSAddr *dstaddr, mDNSIPPort dstport,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome OwnerOptData owner = zeroOwner; // Need to zero this, so we'll know if this Update packet was missing its Owner option
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("Received Update from %#-15a:%-5d to %#-15a:%-5d on 0x%p with "
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome "%2d Question%s %2d Answer%s %2d Authorit%s %2d Additional%s %d bytes",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome srcaddr, mDNSVal16(srcport), dstaddr, mDNSVal16(dstport), InterfaceID,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome msg->h.numQuestions, msg->h.numQuestions == 1 ? ", " : "s,",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome msg->h.numAnswers, msg->h.numAnswers == 1 ? ", " : "s,",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome msg->h.numAuthorities, msg->h.numAuthorities == 1 ? "y, " : "ies,",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome msg->h.numAdditionals, msg->h.numAdditionals == 1 ? " " : "s", end - msg->data);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!InterfaceID || !m->SPSSocket || !mDNSSameIPPort(dstport, m->SPSSocket->port)) return;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome DumpPacket(m, mStatus_NoError, mDNSfalse, "UDP", srcaddr, srcport, dstaddr, dstport, msg, end);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = LocateOptRR(msg, end, DNSOpt_LeaseData_Space + DNSOpt_OwnerData_ID_Space);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = GetLargeResourceRecord(m, msg, ptr, end, 0, kDNSRecordTypePacketAdd, &m->rec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ptr && m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative && m->rec.r.resrec.rrtype == kDNSType_OPT)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const rdataOPT *const e = (const rdataOPT *)&m->rec.r.resrec.rdata->u.data[m->rec.r.resrec.rdlength];
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (o = &m->rec.r.resrec.rdata->u.opt[0]; o < e; o++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (o->opt == kDNSOpt_Lease) updatelease = o->u.updatelease;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (o->opt == kDNSOpt_Owner && o->u.owner.vers == 0) owner = o->u.owner;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome InitializeDNSMessage(&m->omsg.h, msg->h.id, UpdateRespFlags);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("Refusing sleep proxy registration from %#a:%d:%s%s", srcaddr, mDNSVal16(srcport),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome !updatelease ? " No lease" : "", !owner.HMAC.l[0] ? " No owner" : "");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (m->ProxyRecords + msg->h.mDNS_numUpdates > MAX_PROXY_RECORDS)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("Refusing sleep proxy registration from %#a:%d: Too many records %d + %d = %d > %d", srcaddr, mDNSVal16(srcport),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->ProxyRecords, msg->h.mDNS_numUpdates, m->ProxyRecords + msg->h.mDNS_numUpdates, MAX_PROXY_RECORDS);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("Received Update for H-MAC %.6a I-MAC %.6a Password %.6a seq %d", &owner.HMAC, &owner.IMAC, &owner.password, owner.seq);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (updatelease > 0x40000000UL / mDNSPlatformOneSecond)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome updatelease = 0x40000000UL / mDNSPlatformOneSecond;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Clear any stale TCP keepalive records that may exist
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ClearKeepaliveProxyRecords(m, &owner, m->DuplicateRecords, InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ClearKeepaliveProxyRecords(m, &owner, m->ResourceRecords, InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i = 0; i < msg->h.mDNS_numUpdates && ptr && ptr < end; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = GetLargeResourceRecord(m, msg, ptr, end, InterfaceID, kDNSRecordTypePacketAuth, &m->rec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ptr && m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu16 RDLengthMem = GetRDLengthMem(&m->rec.r.resrec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AuthRecord *ar = mDNSPlatformMemAllocate(sizeof(AuthRecord) - sizeof(RDataBody) + RDLengthMem);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu8 RecordType = m->rec.r.resrec.RecordType & kDNSRecordTypePacketUniqueMask ? kDNSRecordTypeUnique : kDNSRecordTypeShared;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rec.r.resrec.rrclass &= ~kDNSClass_UniqueRRSet;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // All stale keepalive records have been flushed prior to this loop.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ClearIdenticalProxyRecords(m, &owner, m->DuplicateRecords); // Make sure we don't have any old stale duplicates of this record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ClearIdenticalProxyRecords(m, &owner, m->ResourceRecords);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetupResourceRecord(ar, mDNSNULL, InterfaceID, m->rec.r.resrec.rrtype, m->rec.r.resrec.rroriginalttl, RecordType, AuthRecordAny, SPSRecordCallback, ar);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName(&ar->namestorage, m->rec.r.resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ar->resrec.rdlength = GetRDLength(&m->rec.r.resrec, mDNSfalse);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformMemCopy(ar->resrec.rdata->u.data, m->rec.r.resrec.rdata->u.data, RDLengthMem);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSs32 t = ReverseMapDomainType(m->rec.r.resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (t == mDNSAddrType_IPv4) GetIPv4FromName(&ar->AddressProxy, m->rec.r.resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (t == mDNSAddrType_IPv6) GetIPv6FromName(&ar->AddressProxy, m->rec.r.resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNSCoreReceiveUpdate: PTR %d %d %#a %s", t, ar->AddressProxy.type, &ar->AddressProxy, ARDisplayString(m, ar));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ar->AddressProxy.type) SetSPSProxyListChanged(InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ar->TimeExpire = m->timenow + updatelease * mDNSPlatformOneSecond;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("SPS Registered %4d %X %s", m->ProxyRecords, RecordType, ARDisplayString(m,ar));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("Refusing sleep proxy registration from %#a:%d: Out of memory", srcaddr, mDNSVal16(srcport));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ClearProxyRecords(m, &owner, m->DuplicateRecords);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ClearProxyRecords(m, &owner, m->ResourceRecords);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetupResourceRecord(&opt, mDNSNULL, mDNSInterface_Any, kDNSType_OPT, kStandardTTL, kDNSRecordTypeKnownUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome opt.resrec.rdlength = sizeof(rdataOPT); // One option in this OPT record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome opt.resrec.rdata->u.opt[0].opt = kDNSOpt_Lease;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome opt.resrec.rdata->u.opt[0].u.updatelease = updatelease;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome p = PutResourceRecordTTLWithLimit(&m->omsg, p, &m->omsg.h.numAdditionals, &opt.resrec, opt.resrec.rroriginalttl, m->omsg.data + AbsoluteMaxDNSMessageData);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (p) mDNSSendDNSMessage(m, &m->omsg, p, InterfaceID, m->SPSSocket, srcaddr, srcport, mDNSNULL, mDNSNULL, mDNSfalse);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNSCoreReceiveUpdateR(mDNS *const m, const DNSMessage *const msg, const mDNSu8 *end, const mDNSAddr *srcaddr, const mDNSInterfaceID InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu32 updatelease = 60 * 60; // If SPS fails to indicate lease time, assume one hour
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu8 *ptr = LocateOptRR(msg, end, DNSOpt_LeaseData_Space);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr = GetLargeResourceRecord(m, msg, ptr, end, 0, kDNSRecordTypePacketAdd, &m->rec);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ptr && m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative && m->rec.r.resrec.rrtype == kDNSType_OPT)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const rdataOPT *const e = (const rdataOPT *)&m->rec.r.resrec.rdata->u.data[m->rec.r.resrec.rdlength];
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (o = &m->rec.r.resrec.rdata->u.opt[0]; o < e; o++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("Sleep Proxy granted lease time %4d seconds, updateid %d, InterfaceID %p", updatelease, mDNSVal16(msg->h.id), InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNSCoreReceiveUpdateR ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.InterfaceID == InterfaceID || (!rr->resrec.InterfaceID && (rr->ForceMCast || IsLocalDomain(rr->resrec.name))))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We successfully completed this record's registration on this "InterfaceID". Clear that bit.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Clear the updateid when we are done sending on all interfaces.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu32 scopeid = mDNSPlatformInterfaceIndexfromInterfaceID(m, InterfaceID, mDNStrue);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (scopeid < (sizeof(rr->updateIntID) * mDNSNBBY))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->expire = NonZeroTime(m->timenow + updatelease * mDNSPlatformOneSecond);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("Sleep Proxy %s record %5d 0x%x 0x%x (%d) %s", rr->WakeUp.HMAC.l[0] ? "transferred" : "registered", updatelease, rr->updateIntID.l[1], rr->updateIntID.l[0], mDNSVal16(rr->updateid), ARDisplayString(m,rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->WakeUp.HMAC = zeroEthAddr; // Clear HMAC so that mDNS_Deregister_internal doesn't waste packets trying to wake this host
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->RequireGoodbye = mDNSfalse; // and we don't want to send goodbye for it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Mustn't advance m->CurrentRecord until *after* mDNS_Deregister_internal, because
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // new records could have been added to the end of the list as a result of that call.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Update the dynamic store with the IP Address and MAC address of the sleep proxy
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformMemCopy(&spsaddr, srcaddr, sizeof (mDNSAddr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we were waiting to go to sleep, then this SPS registration or wide-area record deletion
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // may have been the thing we were waiting for, so schedule another check to see if we can sleep now.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->SleepLimit) m->NextScheduledSPRetry = m->timenow;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void MakeNegativeCacheRecord(mDNS *const m, CacheRecord *const cr,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const domainname *const name, const mDNSu32 namehash, const mDNSu16 rrtype, const mDNSu16 rrclass, mDNSu32 ttl_seconds, mDNSInterfaceID InterfaceID, DNSServer *dnsserver)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (cr == &m->rec.r && m->rec.r.resrec.RecordType)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogFatalError("MakeNegativeCacheRecord: m->rec appears to be already in use for %s", CRDisplayString(m, &m->rec.r));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Create empty resource record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome cr->resrec.RecordType = kDNSRecordTypePacketNegative;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome cr->resrec.name = name; // Will be updated to point to cg->name when we call CreateNewCacheEntry
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome cr->resrec.rdata = (RData*)&cr->smallrdatastorage;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Initialize to the basic one and the caller can set it to more
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // specific based on the response if any
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSexport void mDNSCoreReceive(mDNS *const m, void *const pkt, const mDNSu8 *const end,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSAddr *const srcaddr, const mDNSIPPort srcport, const mDNSAddr *dstaddr, const mDNSIPPort dstport,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu8 StdQ = kDNSFlag0_QR_Query | kDNSFlag0_OP_StdQuery;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu8 StdR = kDNSFlag0_QR_Response | kDNSFlag0_OP_StdQuery;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu8 UpdQ = kDNSFlag0_QR_Query | kDNSFlag0_OP_Update;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu8 UpdR = kDNSFlag0_QR_Response | kDNSFlag0_OP_Update;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSBool TLS = (dstaddr == (mDNSAddr *)1); // For debug logs: dstaddr = 0 means TCP; dstaddr = 1 means TLS
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSSameIPPort(srcport, SSDPPort) || (m->SSDPSocket && mDNSSameIPPort(dstport, m->SSDPSocket->port)))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LNT_ConfigureRouterInfo(m, InterfaceID, pkt, (mDNSu16)(end - (mDNSu8 *)pkt));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome uDNS_ReceiveNATPacket(m, InterfaceID, pkt, (mDNSu16)(end - (mDNSu8 *)pkt));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (m->SSDPSocket && mDNSSameIPPort(dstport, m->SSDPSocket->port)) { debugf("Ignoring SSDP response from %#a:%d", srcaddr, mDNSVal16(srcport)); return; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((unsigned)(end - (mDNSu8 *)pkt) < sizeof(DNSMessageHeader))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("DNS Message from %#a:%d to %#a:%d length %d too short", srcaddr, mDNSVal16(srcport), dstaddr, mDNSVal16(dstport), end - (mDNSu8 *)pkt);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome QR_OP = (mDNSu8)(msg->h.flags.b[0] & kDNSFlag0_QROP_Mask);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Read the integer parts which are in IETF byte-order (MSB first, LSB second)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome msg->h.numQuestions = (mDNSu16)((mDNSu16)ptr[0] << 8 | ptr[1]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome msg->h.numAnswers = (mDNSu16)((mDNSu16)ptr[2] << 8 | ptr[3]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome msg->h.numAuthorities = (mDNSu16)((mDNSu16)ptr[4] << 8 | ptr[5]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome msg->h.numAdditionals = (mDNSu16)((mDNSu16)ptr[6] << 8 | ptr[7]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!m) { LogMsg("mDNSCoreReceive ERROR m is NULL"); return; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We use zero addresses and all-ones addresses at various places in the code to indicate special values like "no address"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we accept and try to process a packet with zero or all-ones source address, that could really mess things up
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (srcaddr && !mDNSAddressIsValid(srcaddr)) { debugf("mDNSCoreReceive ignoring packet from %#a", srcaddr); return; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Track the number of multicast packets received from a source outside our subnet.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Check the destination address to avoid accounting for spurious packets that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // comes in with message id zero.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (!mDNS_AddressIsLocalSubnet(m, InterfaceID, srcaddr) &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // #if APPLE_OSX_mDNSResponder
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!dstaddr || (!mDNSAddressIsAllDNSLinkGroup(dstaddr) && (QR_OP == StdR || QR_OP == UpdR)))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!mDNSOpaque16IsZero(msg->h.id)) // uDNS_ReceiveMsg only needs to get real uDNS responses, not "QU" mDNS responses
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome DumpPacket(m, mStatus_NoError, mDNSfalse, TLS ? "TLS" : !dstaddr ? "TCP" : "UDP", srcaddr, srcport, dstaddr, dstport, msg, end);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome uDNS_ReceiveMsg(m, msg, end, srcaddr, srcport);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: mDNSCore also needs to get access to received unicast responses
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (QR_OP == StdQ) mDNSCoreReceiveQuery (m, msg, end, srcaddr, srcport, dstaddr, dstport, ifid);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (QR_OP == StdR) mDNSCoreReceiveResponse(m, msg, end, srcaddr, srcport, dstaddr, dstport, ifid);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (QR_OP == UpdQ) mDNSCoreReceiveUpdate (m, msg, end, srcaddr, srcport, dstaddr, dstport, InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (QR_OP == UpdR) mDNSCoreReceiveUpdateR (m, msg, end, srcaddr, InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("Unknown DNS packet type %02X%02X from %#-15a:%-5d to %#-15a:%-5d length %d on %p (ignored)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome msg->h.flags.b[0], msg->h.flags.b[1], srcaddr, mDNSVal16(srcport), dstaddr, mDNSVal16(dstport), end - (mDNSu8 *)pkt, InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome char *p = buffer + mDNS_snprintf(buffer, sizeof(buffer), "%04X", i);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome do if (i<end - (mDNSu8 *)pkt) p += mDNS_snprintf(p, sizeof(buffer), " %02X", ((mDNSu8 *)pkt)[i]);while (++i & 15);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Packet reception often causes a change to the task list:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1. Inbound queries can cause us to need to send responses
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2. Conflicing response packets received from other hosts can cause us to need to send defensive responses
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 3. Other hosts announcing deletion of shared records can cause us to need to re-assert those records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 4. Response packets that answer questions may cause our client to issue new questions
4b22b9337f359bfd063322244f5336cc7c6ffcfars// ***************************************************************************
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Targets are considered the same if both queries are untargeted, or
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// if both are targeted to the same address+port
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// (If Target address is zero, TargetPort is undefined)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#define SameQTarget(A,B) (((A)->Target.type == mDNSAddrType_None && (B)->Target.type == mDNSAddrType_None) || \
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (mDNSSameAddress(& (A)->Target, & (B)->Target) && mDNSSameIPPort((A)->TargetPort, (B)->TargetPort)))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Note: We explicitly disallow making a public query be a duplicate of a private one. This is to avoid the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// circular deadlock where a client does a query for something like "dns-sd -Q _dns-query-tls._tcp.company.com SRV"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// and we have a key for company.com, so we try to locate the private query server for company.com, which necessarily entails
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// doing a standard DNS query for the _dns-query-tls._tcp SRV record for company.com. If we make the latter (public) query
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// a duplicate of the former (private) query, then it will block forever waiting for an answer that will never come.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// We keep SuppressUnusable questions separate so that we can return a quick response to them and not get blocked behind
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// the queries that are not marked SuppressUnusable. But if the query is not suppressed, they are treated the same as
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// non-SuppressUnusable questions. This should be fine as the goal of SuppressUnusable is to return quickly only if it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// is suppressed. If it is not suppressed, we do try all the DNS servers for valid answers like any other question.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// The main reason for this design is that cache entries point to a *single* question and that question is responsible
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// for keeping the cache fresh as long as it is active. Having multiple active question for a single cache entry
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// breaks this design principle.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// If IsLLQ(Q) is true, it means the question is both:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// (a) long-lived and
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// (b) being performed by a unicast DNS long-lived query (either full LLQ, or polling)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// for multicast questions, we don't want to treat LongLived as anything special
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#define IsLLQ(Q) ((Q)->LongLived && !mDNSOpaque16IsZero((Q)->TargetQID))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#define IsAWDLIncluded(Q) (((Q)->flags & kDNSServiceFlagsIncludeAWDL) != 0)
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal DNSQuestion *FindDuplicateQuestion(const mDNS *const m, const DNSQuestion *const question)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: A question can only be marked as a duplicate of one that occurs *earlier* in the list.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This prevents circular references, where two questions are each marked as a duplicate of the other.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Accordingly, we break out of the loop when we get to 'question', because there's no point searching
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // further in the list.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (q = m->Questions; q && q != question; q=q->next) // Scan our list for another question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q->InterfaceID == question->InterfaceID && // with the same InterfaceID,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SameQTarget(q, question) && // and same unicast/multicast target settings
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome IsLLQ(q) == IsLLQ(question) && // and long-lived status matches
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (!q->AuthInfo || question->AuthInfo) && // to avoid deadlock, don't make public query dup of a private one
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (q->AnonInfo == question->AnonInfo) && // Anonymous query not a dup of normal query
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (q->SuppressQuery == question->SuppressQuery) && // Questions that are suppressed/not suppressed
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (q->ValidationRequired == question->ValidationRequired) && // Questions that require DNSSEC validation
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (q->ValidatingResponse == question->ValidatingResponse) && // Questions that are validating responses using DNSSEC
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (q->DisallowPID == question->DisallowPID) && // Disallowing a PID should not affect a PID that is allowed
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (q->BrowseThreshold == question->BrowseThreshold) && // browse thresholds must match
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (IsAWDLIncluded(q) == IsAWDLIncluded(question)) && // Inclusion of AWDL interface must match
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SameDomainName(&q->qname, &question->qname)) // and name
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// This is called after a question is deleted, in case other identical questions were being suppressed as duplicates
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void UpdateQuestionDuplicates(mDNS *const m, DNSQuestion *const question)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This is referring to some other question as duplicate. No other question can refer to this
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // question as a duplicate.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("UpdateQuestionDuplicates: question %p %##s (%s) duplicate of %p %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question, question->qname.c, DNSTypeName(question->qtype),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->DuplicateOf, question->DuplicateOf->qname.c, DNSTypeName(question->DuplicateOf->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (q = m->Questions; q; q=q->next) // Scan our list of questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q->DuplicateOf == question) // To see if any questions were referencing this as their duplicate
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If q used to be a duplicate, but now is not,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then inherit the state from the question that's going away
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->ExpectUnicastResp = question->ExpectUnicastResp;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->LastAnswerPktNum = question->LastAnswerPktNum;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->RecentAnswerPkts = question->RecentAnswerPkts;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->validDNSServers = question->validDNSServers;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->unansweredQueries = question->unansweredQueries;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->noServerResponse = question->noServerResponse;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->triedAllServersOnce = question->triedAllServersOnce;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // q->tcp = question->tcp;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->nta = mDNSNULL; // If we've got a GetZoneData in progress, transfer it to the newly active question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // question->tcp = mDNSNULL;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("UpdateQuestionDuplicates transferred LocalSocket pointer for %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("UpdateQuestionDuplicates transferred nta pointer for %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Need to work out how to safely transfer this state too -- appropriate context pointers need to be updated or the code will crash
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (question->tcp) LogInfo("UpdateQuestionDuplicates did not transfer tcp pointer");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("UpdateQuestionDuplicates transferred LLQ state for %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->state = 0; // Must zero question->state, or mDNS_StopQuery_internal will clean up and cancel our LLQ from the server
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport McastResolver *mDNS_AddMcastResolver(mDNS *const m, const domainname *d, const mDNSInterfaceID interface, mDNSu32 timeout)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNS_AddMcastResolver: Adding %##s, InterfaceID %p, timeout %u", d->c, interface, timeout);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (*p) // Check if we already have this {interface, domain} tuple registered
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((*p)->interface == interface && SameDomainName(&(*p)->domain, d))
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (!((*p)->flags & McastResolver_FlagDelete)) LogMsg("Note: Mcast Resolver domain %##s (%p) registered more than once", d->c, interface);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (tmp) *p = tmp; // move to end of list, to ensure ordering from platform layer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // allocate, add to list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome *p = mDNSPlatformMemAllocate(sizeof(**p));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!*p) LogMsg("mDNS_AddMcastResolver: ERROR!! - malloc");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSinline mDNSs32 PenaltyTimeForServer(mDNS *m, DNSServer *server)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This should always be a positive value between 0 and DNSSERVER_PENALTY_TIME
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If it does not get reset in ResetDNSServerPenalties for some reason, we do it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("PenaltyTimeForServer: PenaltyTime negative %d, (server penaltyTime %d, timenow %d) resetting the penalty",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome//Checks to see whether the newname is a better match for the name, given the best one we have
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome//seen so far (given in bestcount).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome//Returns -1 if the newname is not a better match
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome//Returns 0 if the newname is the same as the old match
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome//Returns 1 if the newname is a better match
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal int BetterMatchForName(const domainname *name, int namecount, const domainname *newname, int newcount,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the name contains fewer labels than the new server's domain or the new name
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // contains fewer labels than the current best, then it can't possibly be a better match
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (namecount < newcount || newcount < bestcount) return -1;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If there is no match, return -1 and the caller will skip this newname for
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // selection
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we find a match and the number of labels is the same as bestcount, then
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we return 0 so that the caller can do additional logic to pick one of
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the best based on some other factors e.g., penaltyTime
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we find a match and the number of labels is more than bestcount, then we
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // return 1 so that the caller can pick this over the old one.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: newcount can either be equal or greater than bestcount beause of the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // check above.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SameDomainName(SkipLeadingLabels(name, namecount - newcount), newname))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Normally, we have McastResolvers for .local, in-addr.arpa and ip6.arpa. But there
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// can be queries that can forced to multicast (ForceMCast) even though they don't end in these
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// names. In that case, we give a default timeout of 5 seconds
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSu32 GetTimeoutForMcastQuestion(mDNS *m, DNSQuestion *question)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome int bestmatchlen = -1, namecount = CountLabels(&question->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (curr = m->McastResolvers; curr; curr = curr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome bettermatch = BetterMatchForName(&question->qname, namecount, &curr->domain, currcount, bestmatchlen);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Take the first best match. If there are multiple equally good matches (bettermatch = 0), we take
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the timeout value from the first one
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("GetTimeoutForMcastQuestion: question %##s curmatch %p, Timeout %d", question->qname.c, curmatch,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome curmatch ? curmatch->timeout : DEFAULT_MCAST_TIMEOUT);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome return ( curmatch ? curmatch->timeout : DEFAULT_MCAST_TIMEOUT);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Returns true if it is a Domain Enumeration Query
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport mDNSBool DomainEnumQuery(const domainname *qname)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu8 *mDNS_DEQLabels[] = { (const mDNSu8 *)"\001b", (const mDNSu8 *)"\002db", (const mDNSu8 *)"\002lb",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (const mDNSu8 *)"\001r", (const mDNSu8 *)"\002dr", (const mDNSu8 *)mDNSNULL, };
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We need at least 3 labels (DEQ prefix) + one more label to make a meaningful DE query
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (CountLabels(qname) < 4) { debugf("DomainEnumQuery: question %##s, not enough labels", qname->c); return mDNSfalse; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (mDNS_DEQLabels[i] != (const mDNSu8 *)mDNSNULL)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SameDomainLabel(mDNS_DEQLabels[i], label)) {debugf("DomainEnumQuery: DEQ %##s, label1 match", qname->c); break;}
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNS_DEQLabels[i] == (const mDNSu8 *)mDNSNULL)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("DomainEnumQuery: Not a DEQ %##s, label1 mismatch", qname->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("DomainEnumQuery: DEQ %##s, label1 match", qname->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // CountLabels already verified the number of labels
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome d = (const domainname *)(d->c + 1 + d->c[0]); // Second Label
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!SameDomainLabel(label, (const mDNSu8 *)"\007_dns-sd"))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("DomainEnumQuery: Not a DEQ %##s, label2 mismatch", qname->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("DomainEnumQuery: DEQ %##s, label2 match", qname->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome d = (const domainname *)(d->c + 1 + d->c[0]); // Third Label
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!SameDomainLabel(label, (const mDNSu8 *)"\004_udp"))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("DomainEnumQuery: Not a DEQ %##s, label3 mismatch", qname->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("DomainEnumQuery: DEQ %##s, label3 match", qname->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("DomainEnumQuery: Question %##s is a Domain Enumeration query", qname->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Note: InterfaceID is the InterfaceID of the question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool DNSServerMatch(DNSServer *d, mDNSInterfaceID InterfaceID, mDNSs32 ServiceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1) Unscoped questions (NULL InterfaceID) should consider *only* unscoped DNSServers ( DNSServer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // with "scoped" set to kScopeNone)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2) Scoped questions (non-NULL InterfaceID) should consider *only* scoped DNSServers (DNSServer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // with "scoped" set to kScopeInterfaceId) and their InterfaceIDs should match.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 3) Scoped questions (non-zero ServiceID) should consider *only* scoped DNSServers (DNSServer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // with "scoped" set to kScopeServiceID) and their ServiceIDs should match.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // The first condition in the "if" statement checks to see if both the question and the DNSServer are
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // unscoped. The question is unscoped only if InterfaceID is zero and ServiceID is -1.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the first condition fails, following are the possible cases (the notes below are using
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // InterfaceID for discussion and the same holds good for ServiceID):
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // - DNSServer is not scoped, InterfaceID is not NULL - we should skip the current DNSServer entry
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // as scoped questions should not pick non-scoped DNSServer entry (Refer to (2) above).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // - DNSServer is scoped, InterfaceID is NULL - we should skip the current DNSServer entry as
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // unscoped question should not match scoped DNSServer (Refer to (1) above). The InterfaceID check
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // would fail in this case.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // - DNSServer is scoped and InterfaceID is not NULL - the InterfaceID of the question and the DNSServer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // should match (Refer to (2) above).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: mDNSInterface_Unicast is used only by .local unicast questions and are treated as unscoped.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If a question is scoped both to InterfaceID and ServiceID, the question will be scoped to InterfaceID.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (((d->scoped == kScopeNone) && ((!InterfaceID && ServiceID == -1) || InterfaceID == mDNSInterface_Unicast)) ||
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ((d->scoped == kScopeInterfaceID) && d->interface == InterfaceID) ||
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ((d->scoped == kScopeServiceID) && d->serviceID == ServiceID))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Sets all the Valid DNS servers for a question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport mDNSu32 SetValidDNSServers(mDNS *m, DNSQuestion *question)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome int bestmatchlen = -1, namecount = CountLabels(&question->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (curr = m->DNSServers; curr; curr = curr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("SetValidDNSServers: Parsing DNS server Address %#a (Domain %##s), Scope: %d", &curr->addr, curr->domain.c, curr->scoped);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // skip servers that will soon be deleted
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("SetValidDNSServers: Delete set for index %d, DNS server %#a (Domain %##s), scoped %d", index, &curr->addr, curr->domain.c, curr->scoped);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This happens normally when you unplug the interface where we reset the interfaceID to mDNSInterface_Any for all
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the DNS servers whose scope match the interfaceID. Few seconds later, we also receive the updated DNS configuration.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // But any questions that has mDNSInterface_Any scope that are started/restarted before we receive the update
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (e.g., CheckSuppressUnusableQuestions is called when interfaces are deregistered with the core) should not
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // match the scoped entries by mistake.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: DNS configuration change will help pick the new dns servers but currently it does not affect the timeout
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // Skip DNSServers that are InterfaceID Scoped but have no valid interfaceid set OR DNSServers that are ServiceID Scoped but have no valid serviceid set
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if ((curr->scoped == kScopeInterfaceID && curr->interface == mDNSInterface_Any) || (curr->scoped == kScopeServiceID && curr->serviceID <= 0))
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogInfo("SetValidDNSServers: ScopeType[%d] Skipping DNS server %#a (Domain %##s) Interface:[%p] Serviceid:[%d]", curr->scoped, &curr->addr, curr->domain.c, curr->interface, curr->serviceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((!DEQuery || !curr->cellIntf) && DNSServerMatch(curr, question->InterfaceID, question->ServiceID))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome bettermatch = BetterMatchForName(&question->qname, namecount, &curr->domain, currcount, bestmatchlen);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we found a better match (bettermatch == 1) then clear all the bits
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // corresponding to the old DNSServers that we have may set before and start fresh.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we find an equal match, then include that DNSServer also by setting the corresponding
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("SetValidDNSServers: Resetting all the bits");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("SetValidDNSServers: question %##s Setting the bit for DNS server Address %#a (Domain %##s), Scoped:%d index %d,"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome " Timeout %d, interface %p", question->qname.c, &curr->addr, curr->domain.c, curr->scoped, index, curr->timeout,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("DomainEnumQuery: Question %##s, DNSServer %#a, cell %d", question->qname.c, &curr->addr, curr->cellIntf);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome bit_set_opaque64(question->validDNSServers, index);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("SetValidDNSServers: ValidDNSServer bits 0x%x%x for question %p %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->validDNSServers.l[1], question->validDNSServers.l[0], question, question->qname.c, DNSTypeName(question->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If there are no matching resolvers, then use the default timeout value.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For ProxyQuestion, shorten the timeout so that dig does not timeout on us in case of no response.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome return ((question->ProxyQuestion || question->ValidatingResponse) ? DEFAULT_UDNSSEC_TIMEOUT : timeout ? timeout : DEFAULT_UDNS_TIMEOUT);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Get the Best server that matches a name. If you find penalized servers, look for the one
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// that will come out of the penalty box soon
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal DNSServer *GetBestServer(mDNS *m, const domainname *name, mDNSInterfaceID InterfaceID, mDNSs32 ServiceID, mDNSOpaque64 validBits,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome int bestmatchlen = -1, namecount = name ? CountLabels(name) : 0;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("GetBestServer: ValidDNSServer bits 0x%x%x", validBits.l[1], validBits.l[0]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (curr = m->DNSServers; curr; curr = curr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // skip servers that will soon be deleted
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("GetBestServer: Delete set for index %d, DNS server %#a (Domain %##s), scoped %d", index, &curr->addr, curr->domain.c, curr->scoped);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Check if this is a valid DNSServer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("GetBestServer: continuing for index %d", index);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome currPenaltyTime = PenaltyTimeForServer(m, curr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("GetBestServer: Address %#a (Domain %##s), PenaltyTime(abs) %d, PenaltyTime(rel) %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome &curr->addr, curr->domain.c, curr->penaltyTime, currPenaltyTime);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If there are multiple best servers for a given question, we will pick the first one
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // if none of them are penalized. If some of them are penalized in that list, we pick
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the least penalized one. BetterMatchForName walks through all best matches and
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // "currPenaltyTime < bestPenaltyTime" check lets us either pick the first best server
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // in the list when there are no penalized servers and least one among them
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // when there are some penalized servers.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (DNSServerMatch(curr, InterfaceID, ServiceID))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we know that all the names are already equally good matches, then skip calling BetterMatchForName.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This happens when we initially walk all the DNS servers and set the validity bit on the question.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Actually we just need PenaltyTime match, but for the sake of readability we just skip the expensive
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // part and still do some redundant steps e.g., InterfaceID match
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome bettermatch = BetterMatchForName(name, namecount, &curr->domain, currcount, bestmatchlen);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we found a better match (bettermatch == 1) then we don't need to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // compare penalty times. But if we found an equal match, then we compare
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the penalty times to pick a better match
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((bettermatch == 1) || ((bettermatch == 0) && currPenaltyTime < bestPenaltyTime))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Look up a DNS Server, matching by name and InterfaceID
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal DNSServer *GetServerForName(mDNS *m, const domainname *name, mDNSInterfaceID InterfaceID, mDNSs32 ServiceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome char *ifname = mDNSNULL; // for logging purposes only
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((InterfaceID == mDNSInterface_Unicast) || (InterfaceID == mDNSInterface_LocalOnly))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (InterfaceID) ifname = InterfaceNameForID(m, InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // By passing in all ones, we make sure that every DNS server is considered
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome curmatch = GetBestServer(m, name, InterfaceID, ServiceID, allValid, mDNSNULL, mDNStrue);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("GetServerForName: DNS server %#a:%d (Penalty Time Left %d) (Scope %s:%p) found for name %##s", &curmatch->addr,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSVal16(curmatch->port), (curmatch->penaltyTime ? (curmatch->penaltyTime - m->timenow) : 0), ifname ? ifname : "None",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("GetServerForName: no DNS server (Scope %s:%p) found for name %##s", ifname ? ifname : "None", InterfaceID, name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Look up a DNS Server for a question within its valid DNSServer bits
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport DNSServer *GetServerForQuestion(mDNS *m, DNSQuestion *question)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome char *ifname = mDNSNULL; // for logging purposes only
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSInterfaceID InterfaceID = question->InterfaceID;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((InterfaceID == mDNSInterface_Unicast) || (InterfaceID == mDNSInterface_LocalOnly))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!mDNSOpaque64IsZero(&question->validDNSServers))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome curmatch = GetBestServer(m, name, InterfaceID, question->ServiceID, question->validDNSServers, &currindex, mDNSfalse);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome bit_clr_opaque64(question->validDNSServers, currindex);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("GetServerForQuestion: %p DNS server (%p) %#a:%d (Penalty Time Left %d) (Scope %s:%p:%d) found for name %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question, curmatch, &curmatch->addr, mDNSVal16(curmatch->port),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (curmatch->penaltyTime ? (curmatch->penaltyTime - m->timenow) : 0), ifname ? ifname : "None",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome InterfaceID, question->ServiceID, name, DNSTypeName(question->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("GetServerForQuestion: %p no DNS server (Scope %s:%p:%d) found for name %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question, ifname ? ifname : "None", InterfaceID, question->ServiceID, name, DNSTypeName(question->qtype));
4b22b9337f359bfd063322244f5336cc7c6ffcfars#define ValidQuestionTarget(Q) (((Q)->Target.type == mDNSAddrType_IPv4 || (Q)->Target.type == mDNSAddrType_IPv6) && \
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (mDNSSameIPPort((Q)->TargetPort, UnicastDNSPort) || mDNSSameIPPort((Q)->TargetPort, MulticastDNSPort)))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Called in normal client context (lock not held)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void LLQNATCallback(mDNS *m, NATTraversalInfo *n)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("LLQNATCallback external address:port %.4a:%u, NAT result %d", &n->ExternalAddress, mDNSVal16(n->ExternalPort), n->Result);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome n->clientContext = mDNSNULL; // we received at least one callback since starting this NAT-T
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ActiveQuestion(q) && !mDNSOpaque16IsZero(q->TargetQID) && q->LongLived)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome startLLQHandshake(m, q); // If ExternalPort is zero, will do StartLLQPolling instead
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool IsPrivateDomain(mDNS *const m, DNSQuestion *q)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Skip Private domains as we have special addresses to get the hosts in the Private domain
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AuthInfo = GetAuthInfoForName_internal(m, &q->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (AuthInfo && !AuthInfo->deltime && AuthInfo->AutoTunnel)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("IsPrivateDomain: %##s true", q->qname.c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("IsPrivateDomain: %##s false", q->qname.c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// This function takes the DNSServer as a separate argument because sometimes the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// caller has not yet assigned the DNSServer, but wants to evaluate the SuppressQuery
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// status before switching to it.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool ShouldSuppressUnicastQuery(mDNS *const m, DNSQuestion *q, DNSServer *d)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Some callers don't check for the qtype
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q->qtype != kDNSType_A && q->qtype != kDNSType_AAAA)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ShouldSuppressUnicastQuery: Query not suppressed for %##s, qtype %s, not A/AAAA type", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Private domains are exempted irrespective of what the DNSServer says
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ShouldSuppressUnicastQuery: Query not suppressed for %##s, qtype %s, Private Domain", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ShouldSuppressUnicastQuery: Query suppressed for %##s, qtype %s, as the DNS server is NULL", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Check if the DNS Configuration allows A/AAAA queries to be sent
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ShouldSuppressUnicastQuery: Query not suppressed for %##s, qtype %s, DNSServer %##s %#a:%d allows A queries", q->qname.c,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome DNSTypeName(q->qtype), d->domain.c, &d->addr, mDNSVal16(d->port));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((q->qtype == kDNSType_AAAA) && (d->req_AAAA))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ShouldSuppressUnicastQuery: Query not suppressed for %##s, qtype %s, DNSServer %##s %#a:%d allows AAAA queries", q->qname.c,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome DNSTypeName(q->qtype), d->domain.c, &d->addr, mDNSVal16(d->port));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ShouldSuppressUnicastQuery: Query suppressed for %##s, qtype %s, since DNS Configuration does not allow (req_A is %s and req_AAAA is %s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->qname.c, DNSTypeName(q->qtype), d->req_A ? "true" : "false", d->req_AAAA ? "true" : "false");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool ShouldSuppressDotLocalQuery(mDNS *const m, DNSQuestion *q)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Check to see if there is at least one interface other than loopback and don't suppress
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // .local questions if you find one. If we have at least one interface, it means that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we can send unicast queries for the .local name and we don't want to suppress
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // multicast in that case as upper layers don't know how to handle if we return a
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // negative response for multicast followed by a positive response for unicast.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: we used to check for multicast capable interfaces instead of just any interface
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // present. That did not work in the case where we have a valid interface for unicast
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // but not multicast capable e.g., cellular, as we ended up delivering a negative response
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // first and the upper layer did not wait for the positive response that came later.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = m->HostInterfaces; intf; intf = intf->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ShouldSuppressDotLocalQuery: Found interface %s, not suppressing", intf->ifname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1. If we find a LocalOnly or P2P record answering this question, then don't suppress it.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Set m->CurrentQuestion as it is required by AnswerQuestionWithLORecord.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ret = AnswerQuestionWithLORecord(m, q, mDNStrue);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ShouldSuppressDotLocalQuery: Found LocalOnly record for %##s (%s), not suppressing", q->qname.c,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2. If we find a local AuthRecord answering this question, then don't suppress it.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = m->ResourceRecords; rr; rr = rr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ResourceRecordAnswersQuestion(&rr->resrec, q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ShouldSuppressDotLocalQuery: Found resource record %s for %##s (%s) not suppressing", ARDisplayString(m, rr),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool ShouldSuppressQuery(mDNS *const m, DNSQuestion *q)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q->qtype != kDNSType_A && q->qtype != kDNSType_AAAA)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ShouldSuppressQuery: Query not suppressed for %##s, qtype %s, not A/AAAA type", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We still want the ability to be able to listen to the local services and hence
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // don't fail .local query if we have local records that can potentially answer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the question.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q->InterfaceID != mDNSInterface_Unicast && IsLocalDomain(&q->qname))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ShouldSuppressQuery: Query not suppressed for %##s, qtype %s, Local question", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ShouldSuppressQuery: Query suppressed for %##s, qtype %s, Local question", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome return (ShouldSuppressUnicastQuery(m, q, q->qDNSServer));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void CacheRecordRmvEventsForCurrentQuestion(mDNS *const m, DNSQuestion *q)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Don't deliver RMV events for negative records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType == kDNSRecordTypePacketNegative)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("CacheRecordRmvEventsForCurrentQuestion: CacheRecord %s Suppressing RMV events for question %p %##s (%s), CRActiveQuestion %p, CurrentAnswers %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CRDisplayString(m, rr), q, q->qname.c, DNSTypeName(q->qtype), rr->CRActiveQuestion, q->CurrentAnswers);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SameNameRecordAnswersQuestion(&rr->resrec, q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("CacheRecordRmvEventsForCurrentQuestion: Calling AnswerCurrentQuestionWithResourceRecord (RMV) for question %##s using resource record %s LocalAnswers %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->qname.c, CRDisplayString(m, rr), q->LOAddressAnswers);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.rdlength > SmallRecordLimit) q->LargeAnswers--;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask) q->UniqueAnswers--;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this was the active question for this cache entry, it was the one that was
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // responsible for keeping the cache entry fresh when the cache entry was reaching
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // its expiry. We need to handover the responsibility to someone else. Otherwise,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // when the cache entry is about to expire, we won't find an active question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (pointed by CRActiveQuestion) to refresh the cache.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (qptr = m->Questions; qptr; qptr=qptr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (qptr != q && ActiveQuestion(qptr) && ResourceRecordAnswersQuestion(&rr->resrec, qptr))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("CacheRecordRmvEventsForCurrentQuestion: Updating CRActiveQuestion to %p for cache record %s, "
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome "Original question CurrentAnswers %d, new question CurrentAnswers %d, SuppressUnusable %d, SuppressQuery %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome qptr, CRDisplayString(m,rr), q->CurrentAnswers, qptr->CurrentAnswers, qptr->SuppressUnusable, qptr->SuppressQuery);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->CRActiveQuestion = qptr; // Question used to be active; new value may or may not be null
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!qptr) m->rrcache_active--; // If no longer active, decrement rrcache_active count
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnswerCurrentQuestionWithResourceRecord(m, rr, QC_rmv);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentQuestion != q) break; // If callback deleted q, then we're finished here
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool IsQuestionNew(mDNS *const m, DNSQuestion *question)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool LocalRecordRmvEventsForQuestion(mDNS *const m, DNSQuestion *q)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("LocalRecordRmvEventsForQuestion: ERROR m->CurrentQuestion already set: %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("LocalRecordRmvEventsForQuestion: New Question %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ag = AuthGroupForName(&m->rrauth, slot, q->qnamehash, &q->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Filter the /etc/hosts records - LocalOnly, Unique, A/AAAA/CNAME
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (UniqueLocalOnlyRecord(rr) && LocalOnlyRecordAnswersQuestion(rr, q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("LocalRecordRmvEventsForQuestion: Delivering possible Rmv events with record %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q->CurrentAnswers <= 0 || q->LOAddressAnswers <= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("LocalRecordRmvEventsForQuestion: ERROR!! CurrentAnswers or LOAddressAnswers is zero %p %##s"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome " (%s) CurrentAnswers %d, LOAddressAnswers %d", q, q->qname.c, DNSTypeName(q->qtype),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AnswerLocalQuestionWithLocalAuthRecord(m, rr, QC_rmv); // MUST NOT dereference q again
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentQuestion != q) { m->CurrentQuestion = mDNSNULL; return mDNSfalse; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Returns false if the question got deleted while delivering the RMV events
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// The caller should handle the case
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool CacheRecordRmvEventsForQuestion(mDNS *const m, DNSQuestion *q)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("CacheRecordRmvEventsForQuestion: ERROR m->CurrentQuestion already set: %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If it is a new question, we have not delivered any ADD events yet. So, don't deliver RMV events.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this question was answered using local auth records, then you can't deliver RMVs using cache
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!IsQuestionNew(m, q) && !q->LOAddressAnswers)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentQuestion != q) { m->CurrentQuestion = mDNSNULL; return mDNSfalse; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else { LogInfo("CacheRecordRmvEventsForQuestion: Question %p %##s (%s) is a new question", q, q->qname.c, DNSTypeName(q->qtype)); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void SuppressStatusChanged(mDNS *const m, DNSQuestion *q, DNSQuestion **restart)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // NOTE: CacheRecordRmvEventsForQuestion will not generate RMV events for queries that have non-zero
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // LOAddressAnswers. Hence it is important that we call CacheRecordRmvEventsForQuestion before
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // LocalRecordRmvEventsForQuestion (which decrements LOAddressAnswers)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("SuppressStatusChanged: Question deleted while delivering RMV events from cache");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // SuppressUnusable does not affect questions that are answered from the local records (/etc/hosts)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and SuppressQuery status does not mean anything for these questions. As we are going to stop the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // question below, we need to deliver the RMV events so that the ADDs that will be delivered during
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the restart will not be a duplicate ADD
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("SuppressStatusChanged: Question deleted while delivering RMV events from Local AuthRecords");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // There are two cases here.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1. Previously it was suppressed and now it is not suppressed, restart the question so
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // that it will start as a new question. Note that we can't just call ActivateUnicastQuery
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // because when we get the response, if we had entries in the cache already, it will not answer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // this question if the cache entry did not change. Hence, we need to restart
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the query so that it can be answered from the cache.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2. Previously it was not suppressed and now it is suppressed. We need to restart the questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // so that we redo the duplicate checks in mDNS_StartQuery_internal. A SuppressUnusable question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // is a duplicate of non-SuppressUnusable question if it is not suppressed (SuppressQuery is false).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // A SuppressUnusable question is not a duplicate of non-SuppressUnusable question if it is suppressed
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (SuppressQuery is true). The reason for this is that when a question is suppressed, we want an
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // immediate response and not want to be blocked behind a question that is querying DNS servers. When
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the question is not suppressed, we don't want two active questions sending packets on the wire.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This affects both efficiency and also the current design where there is only one active question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // pointed to from a cache entry.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We restart queries in a two step process by first calling stop and build a temporary list which we
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // will restart at the end. The main reason for the two step process is to handle duplicate questions.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If there are duplicate questions, calling stop inherits the values from another question on the list (which
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // will soon become the real question) including q->ThisQInterval which might be zero if it was
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // suppressed before. At the end when we have restarted all questions, none of them is active as each
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // inherits from one another and we need to reactivate one of the questions here which is a little hacky.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // It is much cleaner and less error prone to build a list of questions and restart at the end.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("SuppressStatusChanged: Stop question %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// The caller should hold the lock
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void CheckSuppressUnusableQuestions(mDNS *const m)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We look through all questions including new questions. During network change events,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we potentially restart questions here in this function that ends up as new questions,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // which may be suppressed at this instance. Before it is handled we get another network
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // event that changes the status e.g., address becomes available. If we did not process
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // new questions, we would never change its SuppressQuery status.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // CurrentQuestion is used by RmvEventsForQuestion below. While delivering RMV events, the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // application callback can potentially stop the current question (detected by CurrentQuestion) or
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *any* other question which could be the next one that we may process here. RestartQuestion
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // points to the "next" question which will be automatically advanced in mDNS_StopQuery_internal
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // if the "next" question is stopped while the CurrentQuestion is stopped
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("CheckSuppressUnusableQuestions: ERROR!! m->RestartQuestion already set: %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->RestartQuestion->qname.c, DNSTypeName(m->RestartQuestion->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Previously it was not suppressed, Generate RMV events for the ADDs that we might have delivered before
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // followed by a negative cache response. Temporarily turn off suppression so that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // AnswerCurrentQuestionWithResourceRecord can answer the question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("CheckSuppressUnusableQuestions: Start question %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void RestartUnicastQuestions(mDNS *const m)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("RestartUnicastQuestions: ERROR!! m->RestartQuestion already set: %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->RestartQuestion->qname.c, DNSTypeName(m->RestartQuestion->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("RestartUnicastQuestions: ERROR!! Restart set for multicast question %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("RestartUnicastQuestions: Start question %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// ValidateParameters() is called by mDNS_StartQuery_internal() to check the client parameters of
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// DNS Question that are already set by the client before calling mDNS_StartQuery()
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mStatus ValidateParameters(mDNS *const m, DNSQuestion *const question)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (question->Target.type && !ValidQuestionTarget(question))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("ValidateParameters: Warning! Target.type = %ld port = %u (Client forgot to initialize before calling mDNS_StartQuery? for question %##s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->Target.type, mDNSVal16(question->TargetPort), question->qname.c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If no question->Target specified, clear TargetPort
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("ValidateParameters: Attempt to start query with invalid qname %##s (%s)", question->qname.c, DNSTypeName(question->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this question is referencing a specific interface, verify it exists
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (question->InterfaceID && question->InterfaceID != mDNSInterface_LocalOnly && question->InterfaceID != mDNSInterface_Unicast && question->InterfaceID != mDNSInterface_P2P)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome NetworkInterfaceInfo *intf = FirstInterfaceForID(m, question->InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ValidateParameters: Note: InterfaceID %d for question %##s (%s) not currently found in active interface list",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (uint32_t)question->InterfaceID, question->qname.c, DNSTypeName(question->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// InitDNSConfig() is called by InitCommonState() to initialize the DNS configuration of the Question.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// These are a subset of the internal uDNS fields. Must be done before ShouldSuppressQuery() & mDNS_PurgeForQuestion()
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void InitDNSConfig(mDNS *const m, DNSQuestion *const question)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // First reset all DNS Configuration
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome mDNSPlatformMemZero(&question->metrics, sizeof(question->metrics));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Need not initialize the DNS Configuration for Local Only OR P2P Questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (question->InterfaceID == mDNSInterface_LocalOnly || question->InterfaceID == mDNSInterface_P2P)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Proceed to initialize DNS Configuration (some are set in SetValidDNSServers())
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu32 timeout = SetValidDNSServers(m, question);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We set the timeout whenever mDNS_StartQuery_internal is called. This means if we have
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // a networking change/search domain change that calls this function again we keep
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // reinitializing the timeout value which means it may never timeout. If this becomes
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // a common case in the future, we can easily fix this by adding extra state that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // indicates that we have already set the StopTime.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note that we set the timeout for all questions. If this turns out to be a duplicate,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // it gets a full timeout value even if the original question times out earlier.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->StopTime = NonZeroTime(m->timenow + timeout * mDNSPlatformOneSecond);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("InitDNSConfig: Setting StopTime on question %p %##s (%s)", question, question->qname.c, DNSTypeName(question->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->qDNSServer = GetServerForQuestion(m, question);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("InitDNSConfig: question %p %##s (%s) Timeout %d, DNS Server %#a:%d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question, question->qname.c, DNSTypeName(question->qtype), timeout,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->qDNSServer ? &question->qDNSServer->addr : mDNSNULL,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSVal16(question->qDNSServer ? question->qDNSServer->port : zp));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->StopTime = NonZeroTime(m->timenow + GetTimeoutForMcastQuestion(m, question) * mDNSPlatformOneSecond);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Set StopTime here since it is a part of DNS Configuration
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // SetNextQueryTime() need not be initialized for LocalOnly OR P2P Questions since those questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // will never be transmitted on the wire. Hence we call SetNextQueryTime() here.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// InitCommonState() is called by mDNS_StartQuery_internal() to initialize the common(uDNS/mDNS) internal
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// state fields of the DNS Question. These are independent of the Client layer.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool InitCommonState(mDNS *const m, DNSQuestion *const question)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: In the case where we already have the answer to this question in our cache, that may be all the client
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // wanted, and they may immediately cancel their question. In this case, sending an actual query on the wire would
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // be a waste. For that reason, we schedule our first query to go out in half a second (InitialQuestionInterval).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If AnswerNewQuestion() finds that we have *no* relevant answers currently in our cache, then it will accelerate
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // that to go out immediately.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // ThisQInterval should be initialized before any memory allocations occur. If malloc
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // debugging is turned on within mDNSResponder (see mDNSDebug.h for details) it validates
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the question list to check if ThisQInterval is negative which means the question has been
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // stopped and can't be on the list. The question is already on the list and ThisQInterval
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // can be negative if the caller just stopped it and starting it again. Hence, it always has to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // be initialized. CheckForSoonToExpireRecords below prints the cache records when logging is
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // turned ON which can allocate memory e.g., base64 encoding, in the case of DNSSEC.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->ThisQInterval = InitialQuestionInterval; // MUST be > zero for an active question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->qnamehash = DomainNameHashValue(&question->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->DelayAnswering = CheckForSoonToExpireRecords(m, &question->qname, question->qnamehash, HashSlot(&question->qname), &purge);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Initial browse threshold used by Finder.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Set the threshold at which we move to a passive browse state,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // not actively sending queries.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (question->flags & kDNSServiceFlagsThresholdOne)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (question->flags & kDNSServiceFlagsThresholdFinder)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->BrowseThreshold = mDNSFinderBrowseThreshold;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#else // APPLE_OSX_mDNSResponder
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // APPLE_OSX_mDNSResponder
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // if kDNSServiceFlagsServiceIndex flag is SET by the client, then do NOT call mDNSPlatformGetDNSRoutePolicy()
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // since we would already have the question->ServiceID in that case.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!(question->flags & kDNSServiceFlagsServiceIndex))
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome mDNSPlatformGetDNSRoutePolicy(m, question, &isCellBlocked);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogInfo("InitCommonState: Query for %##s (%s), PID[%d], EUID[%d], ServiceID[%d] is already set by client", question->qname.c,
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome DNSTypeName(question->qtype), question->pid, question->euid, question->ServiceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->AuthInfo = GetAuthInfoForQuestion(m, question);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->SuppressQuery = ShouldSuppressQuery(m, question);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If ServiceID is 0 or the policy disallows making DNS requests,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // set DisallowPID
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome question->DisallowPID = (question->ServiceID == 0 || (isCellBlocked && question->qDNSServer && question->qDNSServer->cellIntf));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("InitCommonState: Query suppressed for %##s (%s), PID %d/ServiceID %d not allowed", question->qname.c,
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome DNSTypeName(question->qtype), question->pid, question->ServiceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->RequestUnicast = SET_QU_IN_FIRST_FOUR_QUERIES;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#else // mDNS_REQUEST_UNICAST_RESPONSE
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->RequestUnicast = SET_QU_IN_FIRST_QUERY;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // mDNS_REQUEST_UNICAST_RESPONSE
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Request unicast response for first 4 queries to increase
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // reliability in an environment with high multicast packet loss.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Must set to one more than the number of unicast queries you want, since SendQueries()
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // decrements it before calling BuildQuestion() which acts on it.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (question->flags & kDNSServiceFlagsUnicastResponse)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->RequestUnicast = SET_QU_IN_FIRST_FOUR_QUERIES;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("InitCommonState: setting RequestUnicast = %d for %##s (%s)", question->RequestUnicast, question->qname.c,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (question->flags & kDNSServiceFlagsThresholdFinder)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // always send one request with QU bit set when kDNSServiceFlagsThresholdFinder is set
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->RequestUnicast = SET_QU_IN_FIRST_FOUR_QUERIES;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#else // mDNS_REQUEST_UNICAST_RESPONSE
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->RequestUnicast = SET_QU_IN_FIRST_QUERY;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // mDNS_REQUEST_UNICAST_RESPONSE
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("InitCommonState: kDNSServiceFlagsThresholdFinder set, setting RequestUnicast = %d for %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->RequestUnicast, question->qname.c, DNSTypeName(question->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // APPLE_OSX_mDNSResponder
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->WakeOnResolveCount = InitialWakeOnResolveCount;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<DupSuppressInfoSize; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->DupSuppress[i].InterfaceID = mDNSNULL;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("InitCommonState: Question %##s (%s) Interface %p Now %d Send in %d Answer in %d (%p) %s (%p)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->qname.c, DNSTypeName(question->qtype), question->InterfaceID, m->timenow,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->DelayAnswering ? question->DelayAnswering - m->timenow : 0,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question, question->DuplicateOf ? "duplicate of" : "not duplicate", question->DuplicateOf);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("InitCommonState: Delaying answering for %d ticks while cache stabilizes for %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->DelayAnswering - m->timenow, question->qname.c, DNSTypeName(question->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Excludes the DNS Config fields which are already handled by InitDNSConfig()
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void InitWABState(DNSQuestion *const question)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We'll create our question->LocalSocket on demand, if needed.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We won't need one for duplicate questions, or from questions answered immediately out of the cache.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We also don't need one for LLQs because (when we're using NAT) we want them all to share a single
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // NAT mapping for receiving inbound add/remove events.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we don't have our NAT mapping active, start it now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->LLQNAT.clientContext = (void*)1; // Means LLQ NAT Traversal just started
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_StartNATOperation_internal(m, &m->LLQNAT);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void InitLLQState(DNSQuestion *const question)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// InitDNSSECProxyState() is called by mDNS_StartQuery_internal() to initialize
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// DNSSEC & DNS Proxy fields of the DNS Question.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void InitDNSSECProxyState(mDNS *const m, DNSQuestion *const question)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // DNS server selection affects DNSSEC. Turn off validation if req_DO is not set
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // or the request is going over cellular interface.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: This needs to be done here before we call FindDuplicateQuestion as it looks
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // at ValidationRequired setting also.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome debugf("InitDNSSECProxyState: Turning off validation for %##s (%s); going over cell", question->qname.c, DNSTypeName(question->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (DNSSECOptionalQuestion(question) && !(question->qDNSServer->req_DO))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("InitDNSSECProxyState: Turning off validation for %##s (%s); req_DO false",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->qname.c, DNSTypeName(question->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->ValidationRequired = DNSSEC_VALIDATION_NONE;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->ValidationState = (question->ValidationRequired ? DNSSECValRequired : DNSSECValNotRequired);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Once the question is completely initialized including the duplicate logic, this function
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// is called to finalize the unicast question which requires flushing the cache if needed,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// activating the query etc.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void FinalizeUnicastQuestion(mDNS *const m, DNSQuestion *question, mDNSBool purge)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Ensure DNS related info of duplicate question is same as the orig question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->validDNSServers = question->DuplicateOf->validDNSServers;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->qDNSServer = question->DuplicateOf->qDNSServer;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("FinalizeUnicastQuestion: Duplicate question %p (%p) %##s (%s), DNS Server %#a:%d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question, question->DuplicateOf, question->qname.c, DNSTypeName(question->qtype),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->qDNSServer ? &question->qDNSServer->addr : mDNSNULL,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSVal16(question->qDNSServer ? question->qDNSServer->port : zp));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If purge was set above, flush the cache. Need to do this after we set the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // DNS server on the question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (!question->DuplicateOf && DNSSECQuestion(question))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For DNSSEC questions, we need to have the RRSIGs also for verification.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Unlike other initializations, InitLLQNATState should be done after
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we determine that it is a unicast question. LongLived is set for
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // both multicast and unicast browse questions but we should initialize
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the LLQ NAT state only for unicast. Otherwise we will unnecessarily
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // start the NAT traversal that is not needed.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport mStatus mDNS_StartQuery_internal(mDNS *const m, DNSQuestion *const question)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // First check for cache space (can't do queries if there is no cache space allocated)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (question->Target.type || Question_uDNS(question)) ? mDNS_NewMessageID(m) :
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // UNICAST_DISABLED
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_StartQuery_internal: %##s (%s)", question->qname.c, DNSTypeName(question->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: It important that new questions are appended at the *end* of the list, not prepended at the start
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (question->InterfaceID == mDNSInterface_LocalOnly || question->InterfaceID == mDNSInterface_P2P)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (*q && *q != question)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_StartQuery_internal: Error! Tried to add a question %##s (%s) %p that's already in the active list",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->qname.c, DNSTypeName(question->qtype), question);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Intialize the question. The only ordering constraint we have today is that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // InitDNSSECProxyState should be called after the DNS server is selected (in
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // InitCommonState -> InitDNSConfig) as DNS server selection affects DNSSEC
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // validation.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // FindDuplicateQuestion should be called last after all the intialization
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // as the duplicate logic could be potentially based on any field in the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // question.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->DuplicateOf = FindDuplicateQuestion(m, question);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->AuthInfo = question->DuplicateOf->AuthInfo;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (question->InterfaceID == mDNSInterface_LocalOnly || question->InterfaceID == mDNSInterface_P2P)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the question's id is non-zero, then it's Wide Area
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // MUST NOT do this Wide Area setup until near the end of
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // mDNS_StartQuery_internal -- this code may itself issue queries (e.g. SOA,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // NS, etc.) and if we haven't finished setting up our own question and setting
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // m->NewQuestions if necessary then we could end up recursively re-entering
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // this routine with the question list data structures in an inconsistent state.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogInfo("mDNS_StartQuery_internal: NumAllInterfaceRecords %d NumAllInterfaceQuestions %d %##s (%s)",
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome m->NumAllInterfaceRecords, m->NumAllInterfaceQuestions, question->qname.c, DNSTypeName(question->qtype));
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (m->NumAllInterfaceRecords + m->NumAllInterfaceQuestions == 1)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNS_StartQuery_internal: Purging for %##s", question->qname.c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// CancelGetZoneData is an internal routine (i.e. must be called with the lock already held)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void CancelGetZoneData(mDNS *const m, ZoneData *nta)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("CancelGetZoneData %##s (%s)", nta->question.qname.c, DNSTypeName(nta->question.qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This function may be called anytime to free the zone information.The question may or may not have stopped.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If it was already stopped, mDNS_StopQuery_internal would have set q->ThisQInterval to -1 and should not
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // call it again
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("CancelGetZoneData: Question %##s (%s) ThisQInterval %d not -1", nta->question.qname.c, DNSTypeName(nta->question.qtype), nta->question.ThisQInterval);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport mStatus mDNS_StopQuery_internal(mDNS *const m, DNSQuestion *const question)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu32 slot = HashSlot(&question->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheGroup *cg = CacheGroupForName(m, slot, question->qnamehash, &question->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome //LogInfo("mDNS_StopQuery_internal %##s (%s)", question->qname.c, DNSTypeName(question->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (question->InterfaceID == mDNSInterface_LocalOnly || question->InterfaceID == mDNSInterface_P2P) qp = &m->LocalOnlyQuestions;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (*qp && *qp != question) qp=&(*qp)->next;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (question->ThisQInterval >= 0) // Only log error message if the query was supposed to be active
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogFatalError("mDNS_StopQuery_internal: Question %##s (%s) not found in active list", question->qname.c, DNSTypeName(question->qtype));
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (question->InterfaceID != mDNSInterface_LocalOnly && question->InterfaceID != mDNSInterface_P2P && mDNSOpaque16IsZero(question->TargetQID))
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (m->NumAllInterfaceRecords + m->NumAllInterfaceQuestions == 1)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogInfo("mDNS_StopQuery_internal: NumAllInterfaceRecords %d NumAllInterfaceQuestions %d %##s (%s)",
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome m->NumAllInterfaceRecords, m->NumAllInterfaceQuestions, question->qname.c, DNSTypeName(question->qtype));
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (Question_uDNS(question) && !question->metrics.answered)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome queryName = metrics->originalQName ? metrics->originalQName : &question->qname;
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome isForCellular = (question->qDNSServer && question->qDNSServer->cellIntf);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome MetricsUpdateUDNSStats(queryName, mDNSfalse, metrics->querySendCount, 0, isForCellular);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Take care to cut question from list *before* calling UpdateQuestionDuplicates
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // But don't trash ThisQInterval until afterwards.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If there are any cache records referencing this as their active question, then see if there is any
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // other question that is also referencing them, else their CRActiveQuestion needs to get set to NULL.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Checking for ActiveQuestion filters questions that are suppressed also
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // as suppressed questions are not active
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (q = m->Questions; q; q=q->next) // Scan our list of questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ActiveQuestion(q) && ResourceRecordAnswersQuestion(&rr->resrec, q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_StopQuery_internal: Updating CRActiveQuestion to %p for cache record %s, Original question CurrentAnswers %d, new question "
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome "CurrentAnswers %d, SuppressQuery %d", q, CRDisplayString(m,rr), question->CurrentAnswers, q->CurrentAnswers, q->SuppressQuery);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->CRActiveQuestion = q; // Question used to be active; new value may or may not be null
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!q) m->rrcache_active--; // If no longer active, decrement rrcache_active count
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we just deleted the question that CacheRecordAdd() or CacheRecordRmv() is about to look at,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // bump its pointer forward one question.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_StopQuery_internal: Just deleted the currently active question: %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->qname.c, DNSTypeName(question->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_StopQuery_internal: Just deleted a new question that wasn't even answered yet: %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->qname.c, DNSTypeName(question->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->NewLocalOnlyQuestions == question) m->NewLocalOnlyQuestions = question->next;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_StopQuery_internal: Just deleted the current restart question: %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->qname.c, DNSTypeName(question->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNS_StopQuery_internal: Just deleted the current Validation question: %##s (%s)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->qname.c, DNSTypeName(question->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Take care not to trash question->next until *after* we've updated m->CurrentQuestion and m->NewQuestions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // LogMsg("mDNS_StopQuery_internal: Question %##s (%s) removed", question->qname.c, DNSTypeName(question->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // And finally, cancel any associated GetZoneData operation that's still running.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Must not do this until last, because there's a good chance the GetZoneData question is the next in the list,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // so if we delete it earlier in this routine, we could find that our "question->next" pointer above is already
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // invalid before we even use it. By making sure that we update m->CurrentQuestion and m->NewQuestions if necessary
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // *first*, then they're all ready to be updated a second time if necessary when we cancel our GetZoneData query.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (question->tcp) { DisposeTCPConn(question->tcp); question->tcp = mDNSNULL; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (question->LocalSocket) { mDNSPlatformUDPClose(question->LocalSocket); question->LocalSocket = mDNSNULL; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!mDNSOpaque16IsZero(question->TargetQID) && question->LongLived)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Scan our list to see if any more wide-area LLQs remain. If not, stop our NAT Traversal.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!mDNSOpaque16IsZero(q->TargetQID) && q->LongLived) break;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!m->LLQNAT.clientCallback) // Should never happen, but just in case...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_StopQuery ERROR LLQNAT.clientCallback NULL");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->LLQNAT.clientCallback = mDNSNULL; // Means LLQ NAT Traversal not running
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If necessary, tell server it can delete this LLQ state
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we need need to make a TCP connection to cancel the LLQ, that's going to take a little while.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We clear the tcp->question backpointer so that when the TCP connection completes, it doesn't
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // crash trying to access our cancelled question, but we don't cancel the TCP operation itself --
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we let that run out its natural course and complete asynchronously.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // wait until we send the refresh above which needs the nta
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (question->nta) { CancelGetZoneData(m, question->nta); question->nta = mDNSNULL; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (question->ValidationRequired && question->DNSSECAuthInfo)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNS_StopQuery_internal: freeing DNSSECAuthInfo %##s", question->qname.c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->DAIFreeCallback(m, question->DNSSECAuthInfo);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome mDNSPlatformMemFree(question->metrics.originalQName);
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSexport mStatus mDNS_StartQuery(mDNS *const m, DNSQuestion *const question)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome status = mDNS_StartQuery_internal(m, question);
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSexport mStatus mDNS_StopQuery(mDNS *const m, DNSQuestion *const question)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Note that mDNS_StopQueryWithRemoves() does not currently implement the full generality of the other APIs
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Specifically, question callbacks invoked as a result of this call cannot themselves make API calls.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// We invoke the callback without using mDNS_DropLockBeforeCallback/mDNS_ReclaimLockAfterCallback
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// specifically to catch and report if the client callback does try to make API calls
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport mStatus mDNS_StopQueryWithRemoves(mDNS *const m, DNSQuestion *const question)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Check if question is new -- don't want to give remove events for a question we haven't even answered yet
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (qq = m->NewQuestions; qq; qq=qq->next) if (qq == question) break;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu32 slot = HashSlot(&question->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheGroup *const cg = CacheGroupForName(m, slot, question->qnamehash, &question->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("Generating terminal removes for %##s (%s)", question->qname.c, DNSTypeName(question->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType != kDNSRecordTypePacketNegative && SameNameRecordAnswersQuestion(&rr->resrec, question))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Don't use mDNS_DropLockBeforeCallback() here, since we don't allow API calls
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->QuestionCallback(m, question, &rr->resrec, QC_rmv);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport mStatus mDNS_Reconfirm(mDNS *const m, CacheRecord *const cr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome status = mDNS_Reconfirm_internal(m, cr, kDefaultReconfirmTimeForNoAnswer);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (status == mStatus_NoError) ReconfirmAntecedents(m, cr->resrec.name, cr->resrec.namehash, 0);
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSexport mStatus mDNS_ReconfirmByValue(mDNS *const m, ResourceRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_ReconfirmByValue: %p %s", cr, RRDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (cr) status = mDNS_Reconfirm_internal(m, cr, kDefaultReconfirmTimeForNoAnswer);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (status == mStatus_NoError) ReconfirmAntecedents(m, cr->resrec.name, cr->resrec.namehash, 0);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mStatus mDNS_StartBrowse_internal(mDNS *const m, DNSQuestion *const question,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const domainname *const srv, const domainname *const domain,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu8 *anondata, const mDNSInterfaceID InterfaceID, mDNSu32 flags,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSBool ForceMCast, mDNSBool useBackgroundTrafficClass,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->UseBackgroundTrafficClass = useBackgroundTrafficClass;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!ConstructServiceName(&question->qname, mDNSNULL, srv, domain))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->AnonInfo = AllocateAnonInfo(&question->qname, anondata, mDNSPlatformStrLen(anondata), mDNSNULL);
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSexport mStatus mDNS_StartBrowse(mDNS *const m, DNSQuestion *const question,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const domainname *const srv, const domainname *const domain,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu8 *anondata, const mDNSInterfaceID InterfaceID, mDNSu32 flags,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSBool ForceMCast, mDNSBool useBackgroundTrafficClass,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome status = mDNS_StartBrowse_internal(m, question, srv, domain, anondata, InterfaceID, flags, ForceMCast, useBackgroundTrafficClass, Callback, Context);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = m->HostInterfaces; intf; intf = intf->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (intf->ip.type == mDNSAddrType_IPv6) return(mDNStrue);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void FoundServiceInfoSRV(mDNS *const m, DNSQuestion *question, const ResourceRecord *const answer, QC_result AddRecord)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ServiceInfoQuery *query = (ServiceInfoQuery *)question->QuestionContext;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSBool PortChanged = !mDNSSameIPPort(query->info->port, answer->rdata->u.srv.port);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this is our first answer, then set the GotSRV flag and start the address query
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName(&query->qAv4.qname, &answer->rdata->u.srv.target);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName(&query->qAv6.qname, &answer->rdata->u.srv.target);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Only do the AAAA query if this machine actually has IPv6 active
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (MachineHasActiveIPv6(m)) mDNS_StartQuery(m, &query->qAv6);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this is not our first answer, only re-issue the address query if the target host name has changed
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if ((query->qAv4.InterfaceID != query->qSRV.InterfaceID && query->qAv4.InterfaceID != answer->InterfaceID) ||
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome !SameDomainName(&query->qAv4.qname, &answer->rdata->u.srv.target))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (query->qAv6.ThisQInterval >= 0) mDNS_StopQuery(m, &query->qAv6);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SameDomainName(&query->qAv4.qname, &answer->rdata->u.srv.target) && !PortChanged)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we get here, it means:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1. This is not our first SRV answer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2. The interface ID is different, but the target host and port are the same
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This implies that we're seeing the exact same SRV record on more than one interface, so we should
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // make our address queries at least as broad as the original SRV query so that we catch all the answers.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->qAv4.InterfaceID = query->qSRV.InterfaceID; // Will be mDNSInterface_Any, or a specific interface
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->qAv6.InterfaceID = query->qSRV.InterfaceID;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName(&query->qAv4.qname, &answer->rdata->u.srv.target);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName(&query->qAv6.qname, &answer->rdata->u.srv.target);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("FoundServiceInfoSRV: Restarting address queries for %##s (%s)", query->qAv4.qname.c, DNSTypeName(query->qAv4.qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Only do the AAAA query if this machine actually has IPv6 active
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (MachineHasActiveIPv6(m)) mDNS_StartQuery(m, &query->qAv6);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (query->ServiceInfoQueryCallback && query->GotADD && query->GotTXT && PortChanged)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("**** WARNING **** Have given %lu answers for %##s (SRV) %##s %u",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->Answers, query->qSRV.qname.c, answer->rdata->u.srv.target.c,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // CAUTION: MUST NOT do anything more with query after calling query->Callback(), because the client's
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // callback function is allowed to do anything, including deleting this query and freeing its memory.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void FoundServiceInfoTXT(mDNS *const m, DNSQuestion *question, const ResourceRecord *const answer, QC_result AddRecord)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ServiceInfoQuery *query = (ServiceInfoQuery *)question->QuestionContext;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (answer->rdlength > sizeof(query->info->TXTinfo)) return;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->info->TXTinfo[0] = 0; // In case answer->rdlength is zero
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformMemCopy(query->info->TXTinfo, answer->rdata->u.txt.c, answer->rdlength);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome verbosedebugf("FoundServiceInfoTXT: %##s GotADD=%d", query->info->name.c, query->GotADD);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // CAUTION: MUST NOT do anything more with query after calling query->Callback(), because the client's
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // callback function is allowed to do anything, including deleting this query and freeing its memory.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (query->ServiceInfoQueryCallback && query->GotADD)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("**** WARNING **** have given %lu answers for %##s (TXT) %#s...",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->Answers, query->qSRV.qname.c, answer->rdata->u.txt.c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void FoundServiceInfo(mDNS *const m, DNSQuestion *question, const ResourceRecord *const answer, QC_result AddRecord)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ServiceInfoQuery *query = (ServiceInfoQuery *)question->QuestionContext;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome //LogInfo("FoundServiceInfo %d %s", AddRecord, RRDisplayString(m, answer));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("FoundServiceInfo: answer %##s type %d (%s) unexpected", answer->name->c, answer->rrtype, DNSTypeName(answer->rrtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->info->InterfaceID = answer->InterfaceID;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome verbosedebugf("FoundServiceInfo v%ld: %##s GotTXT=%d", query->info->ip.type, query->info->name.c, query->GotTXT);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // CAUTION: MUST NOT do anything more with query after calling query->Callback(), because the client's
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // callback function is allowed to do anything, including deleting this query and freeing its memory.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (query->ServiceInfoQueryCallback && query->GotTXT)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome "**** WARNING **** have given %lu answers for %##s (A) %.4a" :
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome "**** WARNING **** have given %lu answers for %##s (AAAA) %.16a",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->Answers, query->qSRV.qname.c, &answer->rdata->u.data);
4b22b9337f359bfd063322244f5336cc7c6ffcfars// On entry, the client must have set the name and InterfaceID fields of the ServiceInfo structure
4b22b9337f359bfd063322244f5336cc7c6ffcfars// If the query is not interface-specific, then InterfaceID may be zero
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Each time the Callback is invoked, the remainder of the fields will have been filled in
4b22b9337f359bfd063322244f5336cc7c6ffcfars// In addition, InterfaceID will be updated to give the interface identifier corresponding to that response
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSexport mStatus mDNS_StartResolveService(mDNS *const m,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ServiceInfoQuery *query, ServiceInfo *info, mDNSServiceInfoQueryCallback *Callback, void *Context)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->qSRV.ThisQInterval = -1; // So that mDNS_StopResolveService() knows whether to cancel this question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName(&query->qSRV.qname, &info->name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->qSRV.RetryWithSearchDomains = mDNSfalse;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->qSRV.UseBackgroundTrafficClass = mDNSfalse;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->qSRV.QuestionCallback = FoundServiceInfoSRV;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->qTXT.ThisQInterval = -1; // So that mDNS_StopResolveService() knows whether to cancel this question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName(&query->qTXT.qname, &info->name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->qTXT.RetryWithSearchDomains = mDNSfalse;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->qTXT.UseBackgroundTrafficClass = mDNSfalse;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->qTXT.QuestionCallback = FoundServiceInfoTXT;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->qAv4.ThisQInterval = -1; // So that mDNS_StopResolveService() knows whether to cancel this question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->qAv4.RetryWithSearchDomains = mDNSfalse;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->qAv4.UseBackgroundTrafficClass = mDNSfalse;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->qAv4.QuestionCallback = FoundServiceInfo;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->qAv6.ThisQInterval = -1; // So that mDNS_StopResolveService() knows whether to cancel this question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->qAv6.RetryWithSearchDomains = mDNSfalse;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->qAv6.UseBackgroundTrafficClass = mDNSfalse;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome query->qAv6.QuestionCallback = FoundServiceInfo;
4b22b9337f359bfd063322244f5336cc7c6ffcfars// info->name = Must already be set up by client
4b22b9337f359bfd063322244f5336cc7c6ffcfars// info->interface = Must already be set up by client
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We use mDNS_StartQuery_internal here because we're already holding the lock
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome status = mDNS_StartQuery_internal(m, &query->qSRV);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (status == mStatus_NoError) status = mDNS_StartQuery_internal(m, &query->qTXT);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (status != mStatus_NoError) mDNS_StopResolveService(m, query);
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSexport void mDNS_StopResolveService (mDNS *const m, ServiceInfoQuery *q)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We use mDNS_StopQuery_internal here because we're already holding the lock
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q->qSRV.ThisQInterval >= 0) mDNS_StopQuery_internal(m, &q->qSRV);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q->qTXT.ThisQInterval >= 0) mDNS_StopQuery_internal(m, &q->qTXT);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q->qAv4.ThisQInterval >= 0) mDNS_StopQuery_internal(m, &q->qAv4);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q->qAv6.ThisQInterval >= 0) mDNS_StopQuery_internal(m, &q->qAv6);
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSexport mStatus mDNS_GetDomains(mDNS *const m, DNSQuestion *const question, mDNS_DomainType DomainType, const domainname *dom,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSInterfaceID InterfaceID, mDNSQuestionCallback *Callback, void *Context)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome question->UseBackgroundTrafficClass = mDNSfalse;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (DomainType > mDNS_DomainTypeMax) return(mStatus_BadParamErr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!MakeDomainNameFromDNSNameString(&question->qname, mDNS_DomainTypeNames[DomainType])) return(mStatus_BadParamErr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!AppendDomainName(&question->qname, dom)) return(mStatus_BadParamErr);
4b22b9337f359bfd063322244f5336cc7c6ffcfars// ***************************************************************************
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSexport mStatus mDNS_Register(mDNS *const m, AuthRecord *const rr)
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSexport mStatus mDNS_Update(mDNS *const m, AuthRecord *const rr, mDNSu32 newttl,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu16 newrdlength, RData *const newrdata, mDNSRecordUpdateCallback *Callback)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!ValidateRData(rr->resrec.rrtype, newrdlength, newrdata))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("Attempt to update record with invalid rdata: %s", GetRRDisplayString_rdb(&rr->resrec, &newrdata->u, m->MsgBuffer));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If TTL is unspecified, leave TTL unchanged
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (newttl == 0) newttl = rr->resrec.rroriginalttl;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we already have an update queued up which has not gone through yet, give the client a chance to free that memory
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->NewRData = mDNSNULL; // Clear the NewRData pointer ...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->UpdateCallback(m, rr, n, rr->newrdlength); // ...and let the client free this memory, if necessary
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->ARType != AuthRecordLocalOnly && rr->ARType != AuthRecordP2P && !IsLocalDomain(rr->resrec.name))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // The caller frees the memory on error, don't retain stale pointers
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (status != mStatus_NoError) { rr->NewRData = mDNSNULL; rr->newrdlength = 0; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (RRLocalOnly(rr) || (rr->resrec.rroriginalttl == newttl &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.rdlength == newrdlength && mDNSPlatformMemSame(rr->resrec.rdata->u.data, newrdata->u.data, newrdlength)))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (rr->NextUpdateCredit && m->timenow - rr->NextUpdateCredit >= 0) GrantUpdateCredit(rr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!rr->UpdateBlocked && rr->UpdateCredits) rr->UpdateCredits--;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!rr->NextUpdateCredit) rr->NextUpdateCredit = NonZeroTime(m->timenow + kUpdateCreditRefreshInterval);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->AnnounceCount > rr->UpdateCredits + 1) rr->AnnounceCount = (mDNSu8)(rr->UpdateCredits + 1);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu32 delay = 6 - rr->UpdateCredits; // Delay 1 second, then 2, then 3, etc. up to 6 seconds maximum
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!rr->UpdateBlocked) rr->UpdateBlocked = NonZeroTime(m->timenow + (mDNSs32)delay * mDNSPlatformOneSecond);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->LastAPTime = rr->UpdateBlocked - rr->ThisAPInterval;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("Excessive update rate for %##s; delaying announcement by %ld second%s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.name->c, delay, delay > 1 ? "s" : "");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Note: mDNS_Deregister calls mDNS_Deregister_internal which can call a user callback, which may change
4b22b9337f359bfd063322244f5336cc7c6ffcfars// the record list and/or question list.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSexport mStatus mDNS_Deregister(mDNS *const m, AuthRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome status = mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Circular reference: AdvertiseInterface references mDNS_HostNameCallback, which calls mDNS_SetFQDN, which call AdvertiseInterface
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNS_HostNameCallback(mDNS *const m, AuthRecord *const rr, mStatus result);
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal NetworkInterfaceInfo *FindFirstAdvertisedInterface(mDNS *const m)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = m->HostInterfaces; intf; intf = intf->next)
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void AdvertiseInterface(mDNS *const m, NetworkInterfaceInfo *set)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("AdvertiseInterface: Returning due to AutoTargetServices zero for %s", set->ifname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!primary) primary = set; // If no existing advertised interface, this new NetworkInterfaceInfo becomes our new primary
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If interface is marked as a direct link, we can assume the address record is unique
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and does not need to go through the probe phase of the probe/announce packet sequence.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome recordType = (set->DirectLink ? kDNSRecordTypeKnownUnique : kDNSRecordTypeUnique);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("AdvertiseInterface: Marking address record as kDNSRecordTypeKnownUnique for %s", set->ifname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Send dynamic update for non-linklocal IPv4 Addresses
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetupResourceRecord(&set->RR_A, mDNSNULL, set->InterfaceID, kDNSType_A, kHostNameTTL, recordType, AuthRecordAny, mDNS_HostNameCallback, set);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetupResourceRecord(&set->RR_PTR, mDNSNULL, set->InterfaceID, kDNSType_PTR, kHostNameTTL, kDNSRecordTypeKnownUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetupResourceRecord(&set->RR_HINFO, mDNSNULL, set->InterfaceID, kDNSType_HINFO, kHostNameTTL, kDNSRecordTypeUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1. Set up Address record to map from host name ("foo.local.") to IP address
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2. Set up reverse-lookup PTR record to map from our address back to our host name
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName(&set->RR_A.namestorage, &m->MulticastHostname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome set->RR_A.resrec.rdata->u.ipv4 = set->ip.ip.v4;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: This is reverse order compared to a normal dotted-decimal IP address, so we can't use our customary "%.4a" format code
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_snprintf(buffer, sizeof(buffer), "%d.%d.%d.%d.in-addr.arpa.",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome set->ip.ip.v4.b[3], set->ip.ip.v4.b[2], set->ip.ip.v4.b[1], set->ip.ip.v4.b[0]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome set->RR_A.resrec.rdata->u.ipv6 = set->ip.ip.v6;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i = 0; i < 16; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome static const char hexValues[] = "0123456789ABCDEF";
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome buffer[i * 4 ] = hexValues[set->ip.ip.v6.b[15 - i] & 0x0F];
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome buffer[i * 4 + 2] = hexValues[set->ip.ip.v6.b[15 - i] >> 4];
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_snprintf(&buffer[64], sizeof(buffer)-64, "ip6.arpa.");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome MakeDomainNameFromDNSNameString(&set->RR_PTR.namestorage, buffer);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome set->RR_PTR.AutoTarget = Target_AutoHost; // Tell mDNS that the target of this PTR is to be kept in sync with our host name
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome set->RR_PTR.ForceMCast = mDNStrue; // This PTR points to our dot-local name, so don't ever try to write it into a uDNS server
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome set->RR_A.RRSet = &primary->RR_A; // May refer to self
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // must be after the mDNS_Register_internal() calls so that records have complete rdata fields, etc
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // APPLE_OSX_mDNSResponder
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!NO_HINFO && m->HIHardware.c[0] > 0 && m->HISoftware.c[0] > 0 && m->HIHardware.c[0] + m->HISoftware.c[0] <= 254)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu8 *p = set->RR_HINFO.resrec.rdata->u.data;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName(&set->RR_HINFO.namestorage, &m->MulticastHostname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformMemCopy(p, &m->HIHardware, 1 + (mDNSu32)m->HIHardware.c[0]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome p += 1 + (int)p[0];
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformMemCopy(p, &m->HISoftware, 1 + (mDNSu32)m->HISoftware.c[0]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("Not creating HINFO record: platform support layer provided no information");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome set->RR_HINFO.resrec.RecordType = kDNSRecordTypeUnregistered;
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void DeadvertiseInterface(mDNS *const m, NetworkInterfaceInfo *set)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogInfo("DeadvertiseInterface: Returning due to AutoTargetServices zero for %s", set->ifname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Unregister these records.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When doing the mDNS_Exit processing, we first call DeadvertiseInterface for each interface, so by the time the platform
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // support layer gets to call mDNS_DeregisterInterface, the address and PTR records have already been deregistered for it.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Also, in the event of a name conflict, one or more of our records will have been forcibly deregistered.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // To avoid unnecessary and misleading warning messages, we check the RecordType before calling mDNS_Deregister_internal().
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (set->RR_A .resrec.RecordType) mDNS_Deregister_internal(m, &set->RR_A, mDNS_Dereg_normal);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (set->RR_PTR .resrec.RecordType) mDNS_Deregister_internal(m, &set->RR_PTR, mDNS_Dereg_normal);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (set->RR_HINFO.resrec.RecordType) mDNS_Deregister_internal(m, &set->RR_HINFO, mDNS_Dereg_normal);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // APPLE_OSX_mDNSResponder
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void AdvertiseAllInterfaceRecords(mDNS *const m)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = m->HostInterfaces; intf; intf = intf->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("AdvertiseInterface: Advertising for ifname %s", intf->ifname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void DeadvertiseAllInterfaceRecords(mDNS *const m)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = m->HostInterfaces; intf; intf = intf->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("DeadvertiseInterface: Deadvertising for ifname %s", intf->ifname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!AppendDomainLabel(&newmname, &m->hostlabel)) { LogMsg("ERROR: mDNS_SetFQDN: Cannot create MulticastHostname"); return; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!AppendLiteralLabelString(&newmname, "local")) { LogMsg("ERROR: mDNS_SetFQDN: Cannot create MulticastHostname"); return; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SameDomainNameCS(&m->MulticastHostname, &newmname)) debugf("mDNS_SetFQDN - hostname unchanged");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName(&m->MulticastHostname, &newmname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 3. Make sure that any AutoTarget SRV records (and the like) get updated
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = m->ResourceRecords; rr; rr=rr->next) if (rr->AutoTarget) SetTargetToHostName(m, rr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = m->DuplicateRecords; rr; rr=rr->next) if (rr->AutoTarget) SetTargetToHostName(m, rr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNS_HostNameCallback(mDNS *const m, AuthRecord *const rr, mStatus result)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (result == mStatus_NoError) msg = "Name registered";
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (result == mStatus_NameConflict) msg = "Name conflict";
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_HostNameCallback: %##s (%s) %s (%ld)", rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype), msg, result);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Notify the client that the host name is successfully registered
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1. First give the client callback a chance to pick a new name
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2. If the client callback didn't do it, add (or increment) an index ourselves
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This needs to be case-INSENSITIVE compare, because we need to know that the name has been changed so as to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // remedy the conflict, and a name that differs only in capitalization will just suffer the exact same conflict again.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SameDomainLabel(m->hostlabel.c, oldlabel.c))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome IncrementLabelSuffix(&m->hostlabel, mDNSfalse);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 3. Generate the FQDNs from the hostlabel,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and make sure all SRV records, etc., are updated to reference our new hostname
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("Local Hostname %#s.local already in use; will try %#s.local instead", oldlabel.c, m->hostlabel.c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // .local hostnames do not require goodbyes - we ignore the MemFree (which is sent directly by
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // mDNS_Deregister_internal), and allow the caller to deallocate immediately following mDNS_DeadvertiseInterface
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_HostNameCallback: MemFree (ignored)");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_HostNameCallback: Unknown error %d for registration of record %s", result, rr->resrec.name->c);
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void UpdateInterfaceProtocols(mDNS *const m, NetworkInterfaceInfo *active)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = m->HostInterfaces; intf; intf = intf->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (intf->ip.type == mDNSAddrType_IPv4 && intf->McastTxRx) active->IPv4Available = mDNStrue;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (intf->ip.type == mDNSAddrType_IPv6 && intf->McastTxRx) active->IPv6Available = mDNStrue;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void RestartRecordGetZoneData(mDNS * const m)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("RestartRecordGetZoneData: ResourceRecords");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (AuthRecord_uDNS(rr) && rr->state != regState_NoTarget)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("RestartRecordGetZoneData: StartGetZoneData for %##s", rr->resrec.name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Zero out the updateid so that if we have a pending response from the server, it won't
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // be accepted as a valid response. If we accept the response, we might free the new "nta"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->nta) { rr->updateid = zeroID; CancelGetZoneData(m, rr->nta); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->nta = StartGetZoneData(m, rr->resrec.name, ZoneServiceUpdate, RecordRegistrationGotZoneData, rr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void InitializeNetWakeState(mDNS *const m, NetworkInterfaceInfo *set)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We initialize ThisQInterval to -1 indicating that the question has not been started
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // yet. If the question (browse) is started later during interface registration, it will
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // be stopped during interface deregistration. We can't sanity check to see if the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // question has been stopped or not before initializing it to -1 because we need to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // initialize it to -1 the very first time.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<3; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void mDNS_ActivateNetWake_internal(mDNS *const m, NetworkInterfaceInfo *set)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!p) { LogMsg("mDNS_ActivateNetWake_internal: NetworkInterfaceInfo %p not found in active list", set); return; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("ActivateNetWake for %s (%#a)", set->ifname, &set->ip);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_StartBrowse_internal(m, &set->NetWakeBrowse, &SleepProxyServiceType, &localdomain, mDNSNULL, set->InterfaceID, 0, mDNSfalse, mDNSfalse, m->SPSBrowseCallback, set);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void mDNS_DeactivateNetWake_internal(mDNS *const m, NetworkInterfaceInfo *set)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!p) { LogMsg("mDNS_DeactivateNetWake_internal: NetworkInterfaceInfo %p not found in active list", set); return; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: We start the browse only if the interface is NetWake capable and we use this to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // stop the resolves also. Hence, the resolves should not be started without the browse
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // being started i.e, resolves should not happen unless NetWake capable which is
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // guaranteed by BeginSleepProcessing.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("DeactivateNetWake for %s (%#a)", set->ifname, &set->ip);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Stop our browse and resolve operations
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_StopQuery_internal(m, &set->NetWakeBrowse);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<3; i++) if (set->NetWakeResolve[i].ThisQInterval >= 0) mDNS_StopQuery_internal(m, &set->NetWakeResolve[i]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Make special call to the browse callback to let it know it can to remove all records for this interface
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->SPSBrowseCallback(m, &set->NetWakeBrowse, mDNSNULL, QC_rmv);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Reset our variables back to initial state, so we're ready for when NetWake is turned back on
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (includes resetting NetWakeBrowse.ThisQInterval back to -1)
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSexport mStatus mDNS_RegisterInterface(mDNS *const m, NetworkInterfaceInfo *set, mDNSBool flapping)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome { LogMsg("mDNS_RegisterInterface: Error! Tried to register a NetworkInterfaceInfo %#a with zero InterfaceID", &set->ip); return(mStatus_Invalid); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome { LogMsg("mDNS_RegisterInterface: Error! Tried to register a NetworkInterfaceInfo %#a with invalid mask %#a", &set->ip, &set->mask); return(mStatus_Invalid); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Assume this interface will be active now, unless we find a duplicate already in the list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome set->IPv4Available = (mDNSu8)(set->ip.type == mDNSAddrType_IPv4 && set->McastTxRx);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome set->IPv6Available = (mDNSu8)(set->ip.type == mDNSAddrType_IPv6 && set->McastTxRx);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Scan list to see if this InterfaceID is already represented
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_RegisterInterface: Error! Tried to register a NetworkInterfaceInfo that's already in the list");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This InterfaceID already represented by a different interface in the list, so mark this instance inactive for now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (set->ip.type == (*p)->ip.type) FirstOfType = mDNSfalse;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (set->ip.type == mDNSAddrType_IPv4 && set->McastTxRx) (*p)->IPv4Available = mDNStrue;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (set->ip.type == mDNSAddrType_IPv6 && set->McastTxRx) (*p)->IPv6Available = mDNStrue;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNS_RegisterInterface: InterfaceID %d %s (%#a) %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (uint32_t)set->InterfaceID, set->ifname, &set->ip,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome "not represented in list; marking active and retriggering queries" :
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome "already represented in list; marking inactive for now");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (set->NetWake) mDNS_ActivateNetWake_internal(m, set);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // In early versions of OS X the IPv6 address remains on an interface even when the interface is turned off,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // giving the false impression that there's an active representative of this interface when there really isn't.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Therefore, when registering an interface, we want to re-trigger our questions and re-probe our Resource Records,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // even if we believe that we previously had an active representative of this interface.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (set->McastTxRx && (FirstOfType || set->InterfaceActive))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Normally, after an interface comes up, we pause half a second before beginning probing.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This is to guard against cases where there's rapid interface changes, where we could be confused by
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // seeing packets we ourselves sent just moments ago (perhaps when this interface had a different address)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // which are then echoed back after a short delay by some Ethernet switches and some 802.11 base stations.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We don't want to do a probe, and then see a stale echo of an announcement we ourselves sent,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and think it's a conflicting answer to our probe.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // In the case of a flapping interface, we pause for five seconds, and reduce the announcement count to one packet.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSs32 probedelay = flapping ? mDNSPlatformOneSecond * 5 : mDNSPlatformOneSecond / 2;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu8 numannounce = flapping ? (mDNSu8)1 : InitialAnnounceCount;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Use a small amount of randomness:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // In the case of a network administrator turning on an Ethernet hub so that all the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // connected machines establish link at exactly the same time, we don't want them all
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to go and hit the network with identical queries at exactly the same moment.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We set a random delay of up to InitialQuestionInterval (1/3 second).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We must *never* set m->SuppressSending to more than that (or set it repeatedly in a way
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // that causes mDNSResponder to remain in a prolonged state of SuppressSending, because
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // suppressing packet sending for more than about 1/3 second can cause protocol correctness
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to start to break down (e.g. we don't answer probes fast enough, and get name conflicts).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // See <rdar://problem/4073853> mDNS: m->SuppressSending set too enthusiastically
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!m->SuppressSending) m->SuppressSending = m->timenow + (mDNSs32)mDNSRandom((mDNSu32)InitialQuestionInterval);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_RegisterInterface: Frequent transitions for interface %s (%#a)", set->ifname, &set->ip);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNS_RegisterInterface: %s (%#a) probedelay %d", set->ifname, &set->ip, probedelay);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->SuppressProbes - NonZeroTime(m->timenow + probedelay) < 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->SuppressProbes = NonZeroTime(m->timenow + probedelay);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Include OWNER option in packets for 60 seconds after connecting to the network. Setting
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // it here also handles the wake up case as the network link comes UP after waking causing
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // us to reconnect to the network. If we do this as part of the wake up code, it is possible
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // that the network link comes UP after 60 seconds and we never set the OWNER option
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->AnnounceOwner = NonZeroTime(m->timenow + 60 * mDNSPlatformOneSecond);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNS_RegisterInterface: Setting AnnounceOwner");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (q = m->Questions; q; q=q->next) // Scan our list of questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!q->InterfaceID || q->InterfaceID == set->InterfaceID) // If non-specific Q, or Q on this specific interface,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome { // then reactivate this question
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If flapping, delay between first and second queries is nine seconds instead of one second
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSBool dodelay = flapping && (q->FlappingInterface1 == set->InterfaceID || q->FlappingInterface2 == set->InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSs32 initial = dodelay ? InitialQuestionInterval * QuestionIntervalStep2 : InitialQuestionInterval;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSs32 qdelay = dodelay ? mDNSPlatformOneSecond * 5 : 0;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (dodelay) LogInfo("No cache records expired for %##s (%s); okay to delay questions a little", q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!q->ThisQInterval || q->ThisQInterval > initial)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->RequestUnicast = SET_QU_IN_FIRST_FOUR_QUERIES;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#else // mDNS_REQUEST_UNICAST_RESPONSE
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // mDNS_REQUEST_UNICAST_RESPONSE
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->LastQTime = m->timenow - q->ThisQInterval + qdelay;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Change the salt
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For all our non-specific authoritative resource records (and any dormant records specific to this interface)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we now need them to re-probe if necessary, and then re-announce.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!rr->resrec.InterfaceID || rr->resrec.InterfaceID == set->InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Change the salt
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ReInitAnonInfo(&rr->resrec.AnonInfo, rr->resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSCoreRestartRegistration(m, rr, numannounce);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#if APPLE_OSX_mDNSResponder && !TARGET_OS_IPHONE
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Note: mDNS_DeregisterInterface calls mDNS_Deregister_internal which can call a user callback, which may change
4b22b9337f359bfd063322244f5336cc7c6ffcfars// the record list and/or question list.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSexport void mDNS_DeregisterInterface(mDNS *const m, NetworkInterfaceInfo *set, mDNSBool flapping)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Find this record in our list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!*p) { debugf("mDNS_DeregisterInterface: NetworkInterfaceInfo not found in list"); mDNS_Unlock(m); return; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Unlink this record from our list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this interface not the active member of its set, update the v4/v6Available flags for the active member
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = m->HostInterfaces; intf; intf = intf->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (intf->InterfaceActive && intf->InterfaceID == set->InterfaceID)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome intf = FirstInterfaceForID(m, set->InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNS_DeregisterInterface: Another representative of InterfaceID %d %s (%#a) exists;"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome " making it active", (uint32_t)set->InterfaceID, set->ifname, &set->ip);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_DeregisterInterface: ERROR intf->InterfaceActive already set for %s (%#a)", set->ifname, &set->ip);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (intf->NetWake) mDNS_ActivateNetWake_internal(m, intf);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // See if another representative *of the same type* exists. If not, we mave have gone from
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // dual-stack to v6-only (or v4-only) so we need to reconfirm which records are still valid.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (intf = m->HostInterfaces; intf; intf = intf->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (intf->InterfaceID == set->InterfaceID && intf->ip.type == set->ip.type)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNS_DeregisterInterface: Last representative of InterfaceID %d %s (%#a) deregistered;"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome " marking questions etc. dormant", (uint32_t)set->InterfaceID, set->ifname, &set->ip);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogMsg("mDNS_DeregisterInterface: Frequent transitions for interface %s (%#a)", set->ifname, &set->ip);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1. Deactivate any questions specific to this interface, and tag appropriate questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // so that mDNS_RegisterInterface() knows how swiftly it needs to reactivate them
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q->InterfaceID == set->InterfaceID) q->ThisQInterval = 0;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!q->InterfaceID || q->InterfaceID == set->InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->FlappingInterface1 = set->InterfaceID; // Keep history of the last two interfaces to go away
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2. Flush any cache records received on this interface
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome revalidate = mDNSfalse; // Don't revalidate if we're flushing the records
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.InterfaceID == set->InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this interface is deemed flapping,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // postpone deleting the cache records in case the interface comes back again
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For a flapping interface we want these record to go away after 30 seconds
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Reconfirm_internal(m, rr, kDefaultReconfirmTimeForFlappingInterface);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We set UnansweredQueries = MaxUnansweredQueries so we don't waste time doing any queries for them --
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // if the interface does come back, any relevant questions will be reactivated anyway
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // If we still have address records referring to this one, update them.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // This is safe, because this NetworkInterfaceInfo has already been unlinked from the list,
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // so the call to FindFirstAdvertisedInterface() won’t accidentally find it.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome for (intf = m->HostInterfaces; intf; intf = intf->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we were advertising on this interface, deregister those address and reverse-lookup records now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (set->Advertise) DeadvertiseInterface(m, set);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we have any cache records received on this interface that went away, then re-verify them.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // In some versions of OS X the IPv6 address remains on an interface even when the interface is turned off,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // giving the false impression that there's an active representative of this interface when there really isn't.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Don't need to do this when shutting down, because *all* interfaces are about to go away
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.InterfaceID == set->InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Reconfirm_internal(m, rr, kDefaultReconfirmTimeForFlappingInterface);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void SetAnonInfoSRS(ServiceRecordSet *sr, int NumSubTypes)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("SetAnonInfoSRS: Freeing AnonInfo for PTR record %##s, should have been freed already", sr->RR_PTR.resrec.name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome sr->RR_PTR.resrec.AnonInfo = AllocateAnonInfo(sr->RR_PTR.resrec.name, sr->AnonData, len, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<NumSubTypes; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("SetAnonInfoSRS: Freeing AnonInfo for subtype record %##s, should have been freed already", sr->SubTypes[i].resrec.name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome sr->SubTypes[i].resrec.AnonInfo = AllocateAnonInfo(sr->SubTypes[i].resrec.name, sr->AnonData, len, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void ResetAnonInfoSRS(ServiceRecordSet *sr, int NumSubTypes)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<NumSubTypes; i++)
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void ServiceCallback(mDNS *const m, AuthRecord *const rr, mStatus result)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ServiceRecordSet *sr = (ServiceRecordSet *)rr->RecordContext;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (void)m; // Unused parameter
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (result == mStatus_NoError) msg = "Name Registered";
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (result == mStatus_NameConflict) msg = "Name Conflict";
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (result == mStatus_MemFree) msg = "Memory Free";
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("ServiceCallback: %##s (%s) %s (%d)", rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype), msg, result);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Only pass on the NoError acknowledgement for the SRV record (when it finishes probing)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (result == mStatus_NoError && rr != &sr->RR_SRV) return;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we got a name conflict on either SRV or TXT, forcibly deregister this service, and record that we did that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome sr->Conflict = mDNStrue; // Record that this service set had a conflict
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_DeregisterService(m, sr); // Unlink the records from our list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the SRV/TXT/PTR records, or the _services._dns-sd._udp record, or any of the subtype PTR records,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // are still in the process of deregistering, don't pass on the NameConflict/MemFree message until
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // every record is finished cleaning up.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (sr->RR_SRV.resrec.RecordType != kDNSRecordTypeUnregistered) return;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (sr->RR_TXT.resrec.RecordType != kDNSRecordTypeUnregistered) return;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (sr->RR_PTR.resrec.RecordType != kDNSRecordTypeUnregistered) return;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (sr->RR_ADV.resrec.RecordType != kDNSRecordTypeUnregistered) return;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<sr->NumSubTypes; i++) if (sr->SubTypes[i].resrec.RecordType != kDNSRecordTypeUnregistered) return;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (e->r.resrec.RecordType != kDNSRecordTypeUnregistered) return;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If this ServiceRecordSet was forcibly deregistered, and now its memory is ready for reuse,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // then we can now report the NameConflict to the client
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (sr->Conflict) result = mStatus_NameConflict;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("ServiceCallback: All records %s for %##s", (result == mStatus_MemFree ? "Unregistered" : "Registered"), sr->RR_PTR.resrec.name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // CAUTION: MUST NOT do anything more with sr after calling sr->Callback(), because the client's callback
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // function is allowed to do anything, including deregistering this service and freeing its memory.
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void NSSCallback(mDNS *const m, AuthRecord *const rr, mStatus result)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ServiceRecordSet *sr = (ServiceRecordSet *)rr->RecordContext;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal AuthRecType setAuthRecType(mDNSInterfaceID InterfaceID, mDNSu32 flags)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if ((InterfaceID == mDNSInterface_Any) && (flags & coreFlagIncludeP2P)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if ((InterfaceID == mDNSInterface_Any) && (flags & coreFlagIncludeP2P))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if ((InterfaceID == mDNSInterface_Any) && (flags & coreFlagIncludeAWDL))
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Name is first label of domain name (any dots in the name are actual dots, not label separators)
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Type is service type (e.g. "_ipp._tcp.")
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Domain is fully qualified domain name (i.e. ending with a null label)
4b22b9337f359bfd063322244f5336cc7c6ffcfars// We always register a TXT, even if it is empty (so that clients are not
4b22b9337f359bfd063322244f5336cc7c6ffcfars// left waiting forever looking for a nonexistent record.)
4b22b9337f359bfd063322244f5336cc7c6ffcfars// If the host parameter is mDNSNULL or the root domain (ASCII NUL),
4b22b9337f359bfd063322244f5336cc7c6ffcfars// then the default host name (m->MulticastHostname) is automatically used
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// If the optional target host parameter is set, then the storage it points to must remain valid for the lifetime of the service registration
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSexport mStatus mDNS_RegisterService(mDNS *const m, ServiceRecordSet *sr,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const domainlabel *const name, const domainname *const type, const domainname *const domain,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const domainname *const host, mDNSIPPort port, const mDNSu8 txtinfo[], mDNSu16 txtlen,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSInterfaceID InterfaceID, mDNSServiceCallback Callback, void *Context, mDNSu32 flags)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu8 recordType = (flags & coreFlagKnownUnique) ? kDNSRecordTypeKnownUnique : kDNSRecordTypeUnique;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Initialize the AuthRecord objects to sane values
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Need to initialize everything correctly *before* making the decision whether to do a RegisterNoSuchService and bail out
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetupResourceRecord(&sr->RR_ADV, mDNSNULL, InterfaceID, kDNSType_PTR, kStandardTTL, kDNSRecordTypeAdvisory, artype, ServiceCallback, sr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetupResourceRecord(&sr->RR_PTR, mDNSNULL, InterfaceID, kDNSType_PTR, kStandardTTL, kDNSRecordTypeShared, artype, ServiceCallback, sr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SameDomainName(type, (const domainname *) "\x4" "_ubd" "\x4" "_tcp"))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetupResourceRecord(&sr->RR_SRV, mDNSNULL, InterfaceID, kDNSType_SRV, hostTTL, recordType, artype, ServiceCallback, sr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetupResourceRecord(&sr->RR_TXT, mDNSNULL, InterfaceID, kDNSType_TXT, kStandardTTL, kDNSRecordTypeUnique, artype, ServiceCallback, sr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If port number is zero, that means the client is really trying to do a RegisterNoSuchService
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome return(mDNS_RegisterNoSuchService(m, &sr->RR_SRV, name, type, domain, mDNSNULL, InterfaceID, NSSCallback, sr, flags));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the client is registering an oversized TXT record,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // it is the client's responsibility to alloate a ServiceRecordSet structure that is large enough for it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (sr->RR_TXT.resrec.rdata->MaxRDLength < txtlen)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Set up the record names
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For now we only create an advisory record for the main type, not for subtypes
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We need to gain some operational experience before we decide if there's a need to create them for subtypes too
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ConstructServiceName(&sr->RR_ADV.namestorage, (const domainlabel*)"\x09_services", (const domainname*)"\x07_dns-sd\x04_udp", domain) == mDNSNULL)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ConstructServiceName(&sr->RR_PTR.namestorage, mDNSNULL, type, domain) == mDNSNULL) return(mStatus_BadParamErr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ConstructServiceName(&sr->RR_SRV.namestorage, name, type, domain) == mDNSNULL) return(mStatus_BadParamErr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName(&sr->RR_TXT.namestorage, sr->RR_SRV.resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 1. Set up the ADV record rdata to advertise our service type
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName(&sr->RR_ADV.resrec.rdata->u.name, sr->RR_PTR.resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2. Set up the PTR record rdata to point to our service name
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We set up two additionals, so when a client asks for this PTR we automatically send the SRV and the TXT too
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: uDNS registration code assumes that Additional1 points to the SRV record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName(&sr->RR_PTR.resrec.rdata->u.name, sr->RR_SRV.resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 2a. Set up any subtype PTRs to point to our service name
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the client is using subtypes, it is the client's responsibility to have
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // already set the first label of the record name to the subtype being registered
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<NumSubTypes; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName(&st, sr->SubTypes[i].resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome st.c[1+st.c[0]] = 0; // Only want the first label, not the whole FQDN (particularly for mDNS_RenameAndReregisterService())
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetupResourceRecord(&sr->SubTypes[i], mDNSNULL, InterfaceID, kDNSType_PTR, kStandardTTL, kDNSRecordTypeShared, artype, ServiceCallback, sr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ConstructServiceName(&sr->SubTypes[i].namestorage, mDNSNULL, &st, domain) == mDNSNULL) return(mStatus_BadParamErr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName(&sr->SubTypes[i].resrec.rdata->u.name, &sr->RR_SRV.namestorage);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 3. Set up the SRV record rdata.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Setting AutoTarget tells DNS that the target of this SRV is to be automatically kept in sync with our host name
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (host && host->c[0]) AssignDomainName(&sr->RR_SRV.resrec.rdata->u.srv.target, host);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else { sr->RR_SRV.AutoTarget = Target_AutoHost; sr->RR_SRV.resrec.rdata->u.srv.target.c[0] = '\0'; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // 4. Set up the TXT record rdata,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and set DependentOn because we're depending on the SRV record to find and resolve conflicts for us
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: uDNS registration code assumes that DependentOn points to the SRV record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (txtinfo == mDNSNULL) sr->RR_TXT.resrec.rdlength = 0;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (txtinfo != sr->RR_TXT.resrec.rdata->u.txt.c)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (sr->RR_TXT.resrec.rdlength > sr->RR_TXT.resrec.rdata->MaxRDLength) return(mStatus_BadParamErr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformMemCopy(sr->RR_TXT.resrec.rdata->u.txt.c, txtinfo, txtlen);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // It is important that we register SRV first. uDNS assumes that SRV is registered first so
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // that if the SRV cannot find a target, rest of the records that belong to this service
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // will not be activated.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we can't register the SRV record due to errors, bail out. It has not been inserted in
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // any list and hence no need to deregister. We could probably do similar checks for other
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // records below and bail out. For now, this seems to be sufficient to address rdar://9304275
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!err) err = mDNS_Register_internal(m, &sr->RR_TXT);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We register the RR_PTR last, because we want to be sure that in the event of a forced call to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // mDNS_StartExit, the RR_PTR will be the last one to be forcibly deregistered, since that is what triggers
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the mStatus_MemFree callback to ServiceCallback, which in turn passes on the mStatus_MemFree back to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the client callback, which is then at liberty to free the ServiceRecordSet memory at will. We need to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // make sure we've deregistered all our records and done any other necessary cleanup before that happens.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!err) err = mDNS_Register_internal(m, &sr->RR_ADV);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<NumSubTypes; i++) if (!err) err = mDNS_Register_internal(m, &sr->SubTypes[i]);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!err) err = mDNS_Register_internal(m, &sr->RR_PTR);
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSexport mStatus mDNS_AddRecordToService(mDNS *const m, ServiceRecordSet *sr,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ExtraResourceRecord *extra, RData *rdata, mDNSu32 ttl, mDNSu32 flags)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSInterfaceID InterfaceID = sr->RR_PTR.resrec.InterfaceID;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetupResourceRecord(&extra->r, rdata, sr->RR_PTR.resrec.InterfaceID,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome extra->r.resrec.rrtype, ttl, kDNSRecordTypeUnique, artype, ServiceCallback, sr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome AssignDomainName(&extra->r.namestorage, sr->RR_SRV.resrec.name);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (*e) e = &(*e)->next;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_AddRecordToService adding record to %##s %s %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome extra->r.resrec.name->c, DNSTypeName(extra->r.resrec.rrtype), extra->r.resrec.rdlength);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport mStatus mDNS_RemoveRecordFromService(mDNS *const m, ServiceRecordSet *sr, ExtraResourceRecord *extra,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSRecordCallback MemFreeCallback, void *Context)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_RemoveRecordFromService failed to remove record from %##s", extra->r.resrec.name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_RemoveRecordFromService removing record from %##s", extra->r.resrec.name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome status = mDNS_Deregister_internal(m, &extra->r, mDNS_Dereg_normal);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport mStatus mDNS_RenameAndReregisterService(mDNS *const m, ServiceRecordSet *const sr, const domainlabel *newname)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: Don't need to use mDNS_Lock(m) here, because this code is just using public routines
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // mDNS_RegisterService() and mDNS_AddRecordToService(), which do the right locking internally.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const domainname *host = sr->RR_SRV.AutoTarget ? mDNSNULL : &sr->RR_SRV.resrec.rdata->u.srv.target;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome DeconstructServiceName(sr->RR_SRV.resrec.name, &name1, &type, &domain);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("%##s service renamed from \"%#s\" to \"%#s\"", type.c, name1.c, newname->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else debugf("%##s service (domain %##s) renamed from \"%#s\" to \"%#s\"",type.c, domain.c, name1.c, newname->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome err = mDNS_RegisterService(m, sr, newname, &type, &domain,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome host, sr->RR_SRV.resrec.rdata->u.srv.port, sr->RR_TXT.resrec.rdata->u.txt.c, sr->RR_TXT.resrec.rdlength,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome sr->RR_PTR.resrec.InterfaceID, sr->ServiceCallback, sr->ServiceContext, sr->flags);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // mDNS_RegisterService() just reset sr->Extras to NULL.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Fortunately we already grabbed ourselves a copy of this pointer (above), so we can now run
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // through the old list of extra records, and re-add them to our freshly created service registration
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome err = mDNS_AddRecordToService(m, sr, e, e->r.resrec.rdata, e->r.resrec.rroriginalttl, 0);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Note: mDNS_DeregisterService calls mDNS_Deregister_internal which can call a user callback,
4b22b9337f359bfd063322244f5336cc7c6ffcfars// which may change the record list and/or question list.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport mStatus mDNS_DeregisterService_drt(mDNS *const m, ServiceRecordSet *sr, mDNS_Dereg_type drt)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If port number is zero, that means this was actually registered using mDNS_RegisterNoSuchService()
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSIPPortIsZero(sr->RR_SRV.resrec.rdata->u.srv.port)) return(mDNS_DeregisterNoSuchService(m, &sr->RR_SRV));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (sr->RR_PTR.resrec.RecordType == kDNSRecordTypeUnregistered)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("Service set for %##s already deregistered", sr->RR_SRV.resrec.name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (sr->RR_PTR.resrec.RecordType == kDNSRecordTypeDeregistering)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("Service set for %##s already in the process of deregistering", sr->RR_SRV.resrec.name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Avoid race condition:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If a service gets a conflict, then we set the Conflict flag to tell us to generate
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // an mStatus_NameConflict message when we get the mStatus_MemFree for our PTR record.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the client happens to deregister the service in the middle of that process, then
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we clear the flag back to the normal state, so that we deliver a plain mStatus_MemFree
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // instead of incorrectly promoting it to mStatus_NameConflict.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This race condition is exposed particularly when the conformance test generates
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // a whole batch of simultaneous conflicts across a range of services all advertised
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // using the same system default name, and if we don't take this precaution then
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we end up incrementing m->nicelabel multiple times instead of just once.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // <rdar://problem/4060169> Bug when auto-renaming Computer Name after name collision
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We use mDNS_Dereg_repeat because, in the event of a collision, some or all of the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // SRV, TXT, or Extra records could have already been automatically deregistered, and that's okay
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Deregister_internal(m, &sr->RR_SRV, mDNS_Dereg_repeat);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Deregister_internal(m, &sr->RR_TXT, mDNS_Dereg_repeat);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We deregister all of the extra records, but we leave the sr->Extras list intact
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // in case the client wants to do a RenameAndReregister and reinstate the registration
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Deregister_internal(m, &e->r, mDNS_Dereg_repeat);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Deregister_internal(m, &sr->SubTypes[i], drt);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome status = mDNS_Deregister_internal(m, &sr->RR_PTR, drt);
4b22b9337f359bfd063322244f5336cc7c6ffcfars// Create a registration that asserts that no such service exists with this name.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// This can be useful where there is a given function is available through several protocols.
4b22b9337f359bfd063322244f5336cc7c6ffcfars// For example, a printer called "Stuart's Printer" may implement printing via the "pdl-datastream" and "IPP"
4b22b9337f359bfd063322244f5336cc7c6ffcfars// protocols, but not via "LPR". In this case it would be prudent for the printer to assert the non-existence of an
4b22b9337f359bfd063322244f5336cc7c6ffcfars// "LPR" service called "Stuart's Printer". Without this precaution, another printer than offers only "LPR" printing
4b22b9337f359bfd063322244f5336cc7c6ffcfars// could inadvertently advertise its service under the same name "Stuart's Printer", which might be confusing for users.
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSexport mStatus mDNS_RegisterNoSuchService(mDNS *const m, AuthRecord *const rr,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const domainlabel *const name, const domainname *const type, const domainname *const domain,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSInterfaceID InterfaceID, mDNSRecordCallback Callback, void *Context, mDNSu32 flags)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetupResourceRecord(rr, mDNSNULL, InterfaceID, kDNSType_SRV, kHostNameTTL, kDNSRecordTypeUnique, artype, Callback, Context);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ConstructServiceName(&rr->namestorage, name, type, domain) == mDNSNULL) return(mStatus_BadParamErr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (host && host->c[0]) AssignDomainName(&rr->resrec.rdata->u.srv.target, host);
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSexport mStatus mDNS_AdvertiseDomains(mDNS *const m, AuthRecord *rr,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_DomainType DomainType, const mDNSInterfaceID InterfaceID, char *domname)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetupResourceRecord(rr, mDNSNULL, InterfaceID, kDNSType_PTR, kStandardTTL, kDNSRecordTypeShared, artype, mDNSNULL, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!MakeDomainNameFromDNSNameString(&rr->namestorage, mDNS_DomainTypeNames[DomainType])) return(mStatus_BadParamErr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!MakeDomainNameFromDNSNameString(&rr->resrec.rdata->u.name, domname)) return(mStatus_BadParamErr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool mDNS_IdUsedInResourceRecordsList(mDNS * const m, mDNSOpaque16 id)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (r = m->ResourceRecords; r; r=r->next) if (mDNSSameOpaque16(id, r->updateid)) return mDNStrue;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal mDNSBool mDNS_IdUsedInQuestionsList(mDNS * const m, mDNSOpaque16 id)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (q = m->Questions; q; q=q->next) if (mDNSSameOpaque16(id, q->TargetQID)) return mDNStrue;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport mDNSOpaque16 mDNS_NewMessageID(mDNS * const m)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<10; i++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome id = mDNSOpaque16fromIntVal(1 + (mDNSu16)mDNSRandom(0xFFFE));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!mDNS_IdUsedInResourceRecordsList(m, id) && !mDNS_IdUsedInQuestionsList(m, id)) break;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("mDNS_NewMessageID: %5d", mDNSVal16(id));
4b22b9337f359bfd063322244f5336cc7c6ffcfars// ***************************************************************************
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void RestartARPProbing(mDNS *const m, AuthRecord *const rr)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we see an ARP from a machine we think is sleeping, then either
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (i) the machine has woken, or
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (ii) it's just a stray old packet from before the machine slept
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // To handle the second case, we reset ProbeCount, so we'll suppress our own answers for a while, to avoid
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // generating ARP conflicts with a waking machine, and set rr->LastAPTime so we'll start probing again in 10 seconds.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the machine has just woken then we'll discard our records when we see the first new mDNS probe from that machine.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If it was a stray old packet, then after 10 seconds we'll probe again and then start answering ARPs again. In this case we *do*
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // need to send new ARP Announcements, because the owner's ARP broadcasts will have updated neighboring ARP caches, so we need to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // re-assert our (temporary) ownership of that IP address in order to receive subsequent packets addressed to that IPv4 address.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->ProbeCount = DefaultProbeCountForTypeUnique;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we haven't started announcing yet (and we're not already in ten-second-delay mode) the machine is probably
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // still going to sleep, so we just reset rr->ProbeCount so we'll continue probing until it stops responding.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we *have* started announcing, the machine is probably in the process of waking back up, so in that case
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we're more cautious and we wait ten seconds before probing it again. We do this because while waking from
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // sleep, some network interfaces tend to lose or delay inbound packets, and without this delay, if the waking machine
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // didn't answer our three probes within three seconds then we'd announce and cause it an unnecessary address conflict.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->AnnounceCount == InitialAnnounceCount && m->timenow - rr->LastAPTime >= 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->LastAPTime = m->timenow + mDNSPlatformOneSecond * 9; // Send first packet at rr->LastAPTime + rr->ThisAPInterval, i.e. 10 seconds from now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNSCoreReceiveRawARP(mDNS *const m, const ARP_EthIP *const arp, const mDNSInterfaceID InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome static const mDNSOpaque16 ARP_op_request = { { 0, 1 } };
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome NetworkInterfaceInfo *intf = FirstInterfaceForID(m, InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!intf) return;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Process ARP Requests and Probes (but not Announcements), and generate an ARP Reply if necessary.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We also process ARPs from our own kernel (and 'answer' them by injecting a local ARP table entry)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We ignore ARP Announcements here -- Announcements are not questions, they're assertions, so we don't need to answer them.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // The times we might need to react to an ARP Announcement are:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (i) as an indication that the host in question has not gone to sleep yet (so we should delay beginning to proxy for it) or
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (ii) if it's a conflicting Announcement from another host
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // -- and we check for these in Pass 2 below.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSSameOpaque16(arp->op, ARP_op_request) && !mDNSSameIPv4Address(arp->spa, arp->tpa))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.InterfaceID == InterfaceID && rr->resrec.RecordType != kDNSRecordTypeDeregistering &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->AddressProxy.type == mDNSAddrType_IPv4 && mDNSSameIPv4Address(rr->AddressProxy.ip.v4, arp->tpa))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome static const char msg1[] = "ARP Req from owner -- re-probing";
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome static const char msg2[] = "Ignoring ARP Request from ";
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome static const char msg3[] = "Creating Local ARP Cache entry ";
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome static const char msg4[] = "Answering ARP Request from ";
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const char *const msg = mDNSSameEthAddress(&arp->sha, &rr->WakeUp.IMAC) ? msg1 :
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (rr->AnnounceCount == InitialAnnounceCount) ? msg2 :
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSSameEthAddress(&arp->sha, &intf->MAC) ? msg3 : msg4;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("%-7s %s %.6a %.4a for %.4a -- H-MAC %.6a I-MAC %.6a %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome intf->ifname, msg, &arp->sha, &arp->spa, &arp->tpa, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ( rr->ProbeRestartCount < MAX_PROBE_RESTARTS)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("Reached maximum number of restarts for probing - %s", ARDisplayString(m,rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformSetLocalAddressCacheEntry(m, &rr->AddressProxy, &rr->WakeUp.IMAC, InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SendARP(m, 2, rr, &arp->tpa, &arp->sha, &arp->spa, &arp->sha);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For all types of ARP packet we check the Sender IP address to make sure it doesn't conflict with any AddressProxy record we're holding.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (Strictly speaking we're only checking Announcement/Request/Reply packets, since ARP Probes have zero Sender IP address,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // so by definition (and by design) they can never conflict with any real (i.e. non-zero) IP address).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We ignore ARPs we sent ourselves (Sender MAC address is our MAC address) because our own proxy ARPs do not constitute a conflict that we need to handle.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we see an apparently conflicting ARP, we check the sender hardware address:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the sender hardware address is the original owner this is benign, so we just suppress our own proxy answering for a while longer.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the sender hardware address is *not* the original owner, then this is a conflict, and we need to wake the sleeping machine to handle it.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!mDNSSameIPv4Address(arp->spa, zerov4Addr))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.InterfaceID == InterfaceID && rr->resrec.RecordType != kDNSRecordTypeDeregistering &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->AddressProxy.type == mDNSAddrType_IPv4 && mDNSSameIPv4Address(rr->AddressProxy.ip.v4, arp->spa) && (rr->ProbeRestartCount < MAX_PROBE_RESTARTS))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSSameEthAddress(&zeroEthAddr, &rr->WakeUp.HMAC))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("%-7s ARP from %.6a %.4a for %.4a -- Invalid H-MAC %.6a I-MAC %.6a %s", intf->ifname,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome &arp->sha, &arp->spa, &arp->tpa, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSSameEthAddress(&arp->sha, &rr->WakeUp.IMAC))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("%-7s ARP %s from owner %.6a %.4a for %-15.4a -- re-starting probing for %s", intf->ifname,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSSameIPv4Address(arp->spa, arp->tpa) ? "Announcement " : mDNSSameOpaque16(arp->op, ARP_op_request) ? "Request " : "Response ",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome &arp->sha, &arp->spa, &arp->tpa, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("%-7s Conflicting ARP from %.6a %.4a for %.4a -- waking H-MAC %.6a I-MAC %.6a %s", intf->ifname,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome &arp->sha, &arp->spa, &arp->tpa, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ScheduleWakeup(m, rr->resrec.InterfaceID, &rr->WakeUp.HMAC);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Option 1 is Source Link Layer Address Option
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Option 2 is Target Link Layer Address Option
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSlocal const mDNSEthAddr *GetLinkLayerAddressOption(const IPv6NDP *const ndp, const mDNSu8 *const end, mDNSu8 op)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu8 *options = (mDNSu8 *)(ndp+1);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (options < end)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("NDP Option %02X len %2d %d", options[0], options[1], end - options);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (options[0] == op && options[1] == 1) return (const mDNSEthAddr*)(options+2);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome options += options[1] * 8;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome return mDNSNULL;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNSCoreReceiveRawND(mDNS *const m, const mDNSEthAddr *const sha, const mDNSv6Addr *spa,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const IPv6NDP *const ndp, const mDNSu8 *const end, const mDNSInterfaceID InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome NetworkInterfaceInfo *intf = FirstInterfaceForID(m, InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!intf) return;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Pass 1: Process Neighbor Solicitations, and generate a Neighbor Advertisement if necessary.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome //const mDNSEthAddr *const sha = GetLinkLayerAddressOption(ndp, end, NDP_SrcLL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.InterfaceID == InterfaceID && rr->resrec.RecordType != kDNSRecordTypeDeregistering &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->AddressProxy.type == mDNSAddrType_IPv6 && mDNSSameIPv6Address(rr->AddressProxy.ip.v6, ndp->target))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome static const char msg1[] = "NDP Req from owner -- re-probing";
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome static const char msg2[] = "Ignoring NDP Request from ";
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome static const char msg3[] = "Creating Local NDP Cache entry ";
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome static const char msg4[] = "Answering NDP Request from ";
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome static const char msg5[] = "Answering NDP Probe from ";
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const char *const msg = sha && mDNSSameEthAddress(sha, &rr->WakeUp.IMAC) ? msg1 :
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (rr->AnnounceCount == InitialAnnounceCount) ? msg2 :
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome sha && mDNSSameEthAddress(sha, &intf->MAC) ? msg3 :
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome spa && mDNSIPv6AddressIsZero(*spa) ? msg4 : msg5;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("%-7s %s %.6a %.16a for %.16a -- H-MAC %.6a I-MAC %.6a %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome intf->ifname, msg, sha, spa, &ndp->target, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->ProbeRestartCount < MAX_PROBE_RESTARTS)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("Reached maximum number of restarts for probing - %s", ARDisplayString(m,rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformSetLocalAddressCacheEntry(m, &rr->AddressProxy, &rr->WakeUp.IMAC, InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SendNDP(m, NDP_Adv, NDP_Solicited, rr, &ndp->target, mDNSNULL, spa, sha);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SendNDP(m, NDP_Adv, 0, rr, &ndp->target, mDNSNULL, &AllHosts_v6, &AllHosts_v6_Eth);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Pass 2: For all types of NDP packet we check the Sender IP address to make sure it doesn't conflict with any AddressProxy record we're holding.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("NDP from self for %.16a", &ndp->target);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For Neighbor Advertisements we check the Target address field, not the actual IPv6 source address.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When a machine has both link-local and routable IPv6 addresses, it may send NDP packets making assertions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // about its routable IPv6 address, using its link-local address as the source address for all NDP packets.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Hence it is the NDP target address we care about, not the actual packet source address.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.InterfaceID == InterfaceID && rr->resrec.RecordType != kDNSRecordTypeDeregistering &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->AddressProxy.type == mDNSAddrType_IPv6 && mDNSSameIPv6Address(rr->AddressProxy.ip.v6, *spa) && (rr->ProbeRestartCount < MAX_PROBE_RESTARTS))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSSameEthAddress(&zeroEthAddr, &rr->WakeUp.HMAC))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("%-7s NDP from %.6a %.16a for %.16a -- Invalid H-MAC %.6a I-MAC %.6a %s", intf->ifname,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome sha, spa, &ndp->target, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("%-7s NDP %s from owner %.6a %.16a for %.16a -- re-starting probing for %s", intf->ifname,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ndp->type == NDP_Sol ? "Solicitation " : "Advertisement", sha, spa, &ndp->target, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("%-7s Conflicting NDP from %.6a %.16a for %.16a -- waking H-MAC %.6a I-MAC %.6a %s", intf->ifname,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome sha, spa, &ndp->target, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ScheduleWakeup(m, rr->resrec.InterfaceID, &rr->WakeUp.HMAC);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNSCoreReceiveRawTransportPacket(mDNS *const m, const mDNSEthAddr *const sha, const mDNSAddr *const src, const mDNSAddr *const dst, const mDNSu8 protocol,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu8 *const p, const TransportLayerPacket *const t, const mDNSu8 *const end, const mDNSInterfaceID InterfaceID, const mDNSu16 len)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSIPPort port = (protocol == 0x06) ? t->tcp.dst : (protocol == 0x11) ? t->udp.dst : zeroIPPort;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome #define XX wake ? "Received" : "Ignoring", end-p
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome case 0x01: LogSPS("Ignoring %d-byte ICMP from %#a to %#a", end-p, src, dst);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome case 0x06: {
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome kr = mDNS_MatchKeepaliveInfo(m, dst, src, port, t->tcp.src, &seq, &ack);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("mDNSCoreReceiveRawTransportPacket: Found a Keepalive record from %#a:%d to %#a:%d", src, mDNSVal16(t->tcp.src), dst, mDNSVal16(port));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Plan to wake if
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (a) RST or FIN is set (the keepalive that we sent could have caused a reset)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (b) packet that contains new data and acks a sequence number higher than the one
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we have been sending in the keepalive
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome wake = ((t->tcp.flags & TH_RST) || (t->tcp.flags & TH_FIN)) ;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Convert to host order
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome seq = ptr[0] << 24 | ptr[1] << 16 | ptr[2] << 8 | ptr[3];
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ack = ptr[0] << 24 | ptr[1] << 16 | ptr[2] << 8 | ptr[3];
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome pseq = ptr[0] << 24 | ptr[1] << 16 | ptr[2] << 8 | ptr[3];
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome pack = ptr[0] << 24 | ptr[1] << 16 | ptr[2] << 8 | ptr[3];
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If the other side is acking one more than our sequence number (keepalive is one
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // less than the last valid sequence sent) and it's sequence is more than what we
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // acked before
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome //if (end - p - 34 - ((t->tcp.offset >> 4) * 4) > 0) data = mDNStrue;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (end - ((mDNSu8 *)t + tcphlen) > 0) data = mDNStrue;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome wake = ((int)(pack - seq) > 0) && ((int)(pseq - ack) >= 0) && data;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we got a regular keepalive on a connection that was registed with the KeepAlive API, respond with an ACK
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((t->tcp.flags & TH_ACK) && (data == mDNSfalse) &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Send an ACK;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("mDNSCoreReceiveRawTransportPacket: End %p, hlen %d, Datalen %d, pack %u, seq %u, pseq %u, ack %u, wake %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome end, tcphlen, end - ((mDNSu8 *)t + tcphlen), pack, seq, pseq, ack, wake);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else { LogSPS("mDNSCoreReceiveRawTransportPacket: waking because of RST or FIN th_flags %d", t->tcp.flags); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Plan to wake if
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (a) RST is not set, AND
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (b) packet is SYN, SYN+FIN, or plain data packet (no SYN or FIN). We won't wake for FIN alone.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome wake = (!(t->tcp.flags & TH_RST) && (t->tcp.flags & (TH_FIN|TH_SYN)) != TH_FIN);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For now, to reduce spurious wakeups, we wake only for TCP SYN,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // except for ssh connections, where we'll wake for plain data packets too
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!mDNSSameIPPort(port, SSHPort) && !(t->tcp.flags & 2)) wake = mDNSfalse;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("%s %d-byte TCP from %#a:%d to %#a:%d%s%s%s", XX,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome src, mDNSVal16(t->tcp.src), dst, mDNSVal16(port),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome case 0x11: {
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome static const mDNSIPPort ARD = { { ARD_AsNumber >> 8, ARD_AsNumber & 0xFF } };
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu16 udplen = (mDNSu16)((mDNSu16)t->bytes[4] << 8 | t->bytes[5]); // Length *including* 8-byte UDP header
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu16 datalen = udplen - sizeof(UDPHeader);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For Back to My Mac UDP port 4500 (IPSEC) packets, we do some special handling
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Specifically ignore NAT keepalive packets
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (datalen == 1 && end >= &t->bytes[9] && t->bytes[8] == 0xFF) wake = mDNSfalse;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Skip over the Non-ESP Marker if present
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSBool NonESP = (end >= &t->bytes[12] && t->bytes[8] == 0 && t->bytes[9] == 0 && t->bytes[10] == 0 && t->bytes[11] == 0);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const IKEHeader *const ike = (IKEHeader *)(t + (NonESP ? 12 : 8));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu16 ikelen = datalen - (NonESP ? 4 : 0);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ikelen >= sizeof(IKEHeader) && end >= ((mDNSu8 *)ike) + sizeof(IKEHeader))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // ExchangeType == 5 means 'Informational' <http://www.ietf.org/rfc/rfc2408.txt>
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // ExchangeType == 34 means 'IKE_SA_INIT' <http://www.iana.org/assignments/ikev2-parameters>
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (ike->ExchangeType == 5 || ike->ExchangeType == 34) wake = mDNSfalse;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("%s %d-byte IKE ExchangeType %d", XX, ike->ExchangeType);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For now, because we haven't yet worked out a clean elegant way to do this, we just special-case the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Apple Remote Desktop port number -- we ignore all packets to UDP 3283 (the "Net Assistant" port),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // except for Apple Remote Desktop's explicit manual wakeup packet, which looks like this:
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // UDP header (8 bytes)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Payload: 13 88 00 6a 41 4e 41 20 (8 bytes) ffffffffffff (6 bytes) 16xMAC (96 bytes) = 110 bytes total
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSSameIPPort(port, ARD)) wake = (datalen >= 110 && end >= &t->bytes[10] && t->bytes[8] == 0x13 && t->bytes[9] == 0x88);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("%s %d-byte UDP from %#a:%d to %#a:%d", XX, src, mDNSVal16(t->udp.src), dst, mDNSVal16(port));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSu16 checksum = IPv6CheckSum(&src->ip.v6, &dst->ip.v6, protocol, t->bytes, len);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!checksum) mDNSCoreReceiveRawND(m, sha, &src->ip.v6, &t->ndp, &t->bytes[len], InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else LogInfo("IPv6CheckSum bad %04X %02X%02X from %#a to %#a", checksum, t->bytes[2], t->bytes[3], src, dst);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome default: LogSPS("Ignoring %d-byte IP packet unknown protocol %d from %#a to %#a", end-p, protocol, src, dst);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->resrec.RecordType != kDNSRecordTypeDeregistering &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->AddressProxy.type && mDNSSameAddress(&rr->AddressProxy, dst))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu8 *const tp = (protocol == 6) ? (const mDNSu8 *)"\x4_tcp" : (const mDNSu8 *)"\x4_udp";
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (r2->resrec.InterfaceID == InterfaceID && mDNSSameEthAddress(&r2->WakeUp.HMAC, &rr->WakeUp.HMAC) &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome r2->resrec.RecordType != kDNSRecordTypeDeregistering &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome r2->resrec.rrtype == kDNSType_SRV && mDNSSameIPPort(r2->resrec.rdata->u.srv.port, port) &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SameDomainLabel(ThirdLabel(r2->resrec.name)->c, tp))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!r2 && mDNSSameIPPort(port, IPSECPort)) r2 = rr; // So that we wake for BTMM IPSEC packets, even without a matching SRV record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!r2 && kaWake) r2 = rr; // So that we wake for keepalive packets, even without a matching SRV record
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("Waking host at %s %#a H-MAC %.6a I-MAC %.6a for %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome InterfaceNameForID(m, rr->resrec.InterfaceID), dst, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m, r2));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ScheduleWakeup(m, rr->resrec.InterfaceID, &rr->WakeUp.HMAC);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("Sleeping host at %s %#a %.6a has no service on %#s %d",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome InterfaceNameForID(m, rr->resrec.InterfaceID), dst, &rr->WakeUp.HMAC, tp, mDNSVal16(port));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void mDNSCoreReceiveRawPacket(mDNS *const m, const mDNSu8 *const p, const mDNSu8 *const end, const mDNSInterfaceID InterfaceID)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome static const mDNSOpaque16 Ethertype_ARP = { { 0x08, 0x06 } }; // Ethertype 0x0806 = ARP
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome static const mDNSOpaque16 Ethertype_IPv4 = { { 0x08, 0x00 } }; // Ethertype 0x0800 = IPv4
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome static const mDNSOpaque16 Ethertype_IPv6 = { { 0x86, 0xDD } }; // Ethertype 0x86DD = IPv6
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome static const mDNSOpaque16 ARP_hrd_eth = { { 0x00, 0x01 } }; // Hardware address space (Ethernet = 1)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome static const mDNSOpaque16 ARP_pro_ip = { { 0x08, 0x00 } }; // Protocol address space (IP = 0x0800)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: BPF guarantees that the NETWORK LAYER header will be word aligned, not the link-layer header.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // In other words, we can safely assume that pkt below (ARP, IPv4 or IPv6) is properly word aligned,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // but if pkt is 4-byte aligned, that necessarily means that eth CANNOT also be 4-byte aligned
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // since it points to a an address 14 bytes before pkt.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const EthernetHeader *const eth = (const EthernetHeader *)p;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const NetworkLayerPacket *const pkt = (const NetworkLayerPacket *)(eth+1);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome #define RequiredCapLen(P) ((P)==0x01 ? 4 : (P)==0x06 ? 20 : (P)==0x11 ? 8 : (P)==0x3A ? 24 : 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Is ARP? Length must be at least 14 + 28 = 42 bytes
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (end >= p+42 && mDNSSameOpaque16(eth->ethertype, Ethertype_ARP) && mDNSSameOpaque16(pkt->arp.hrd, ARP_hrd_eth) && mDNSSameOpaque16(pkt->arp.pro, ARP_pro_ip))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSCoreReceiveRawARP(m, &pkt->arp, InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Is IPv4 with zero fragmentation offset? Length must be at least 14 + 20 = 34 bytes
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (end >= p+34 && mDNSSameOpaque16(eth->ethertype, Ethertype_IPv4) && (pkt->v4.flagsfrags.b[0] & 0x1F) == 0 && pkt->v4.flagsfrags.b[1] == 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome const mDNSu8 *const trans = p + 14 + (pkt->v4.vlen & 0xF) * 4;
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome const mDNSu8 * transEnd = p + 14 + mDNSVal16(pkt->v4.totlen);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("Got IPv4 %02X from %.4a to %.4a", pkt->v4.protocol, &pkt->v4.src, &pkt->v4.dst);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome src.type = mDNSAddrType_IPv4; src.ip.v4 = pkt->v4.src;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome dst.type = mDNSAddrType_IPv4; dst.ip.v4 = pkt->v4.dst;
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (transEnd >= trans + RequiredCapLen(pkt->v4.protocol))
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome mDNSCoreReceiveRawTransportPacket(m, ð->src, &src, &dst, pkt->v4.protocol, p, (TransportLayerPacket*)trans, transEnd, InterfaceID, 0);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Is IPv6? Length must be at least 14 + 28 = 42 bytes
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else if (end >= p+54 && mDNSSameOpaque16(eth->ethertype, Ethertype_IPv6))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("Got IPv6 %02X from %.16a to %.16a", pkt->v6.pro, &pkt->v6.src, &pkt->v6.dst);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome src.type = mDNSAddrType_IPv6; src.ip.v6 = pkt->v6.src;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome dst.type = mDNSAddrType_IPv6; dst.ip.v6 = pkt->v6.dst;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (end >= trans + RequiredCapLen(pkt->v6.pro))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSCoreReceiveRawTransportPacket(m, ð->src, &src, &dst, pkt->v6.pro, p, (TransportLayerPacket*)trans, end, InterfaceID,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void ConstructSleepProxyServerName(mDNS *const m, domainlabel *name)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome name->c[0] = (mDNSu8)mDNS_snprintf((char*)name->c+1, 62, "%d-%d-%d-%d.%d %#s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->SPSType, m->SPSPortability, m->SPSMarginalPower, m->SPSTotalPower, m->SPSFeatureFlags, &m->nicelabel);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void SleepProxyServerCallback(mDNS *const m, ServiceRecordSet *const srs, mStatus result)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_RenameAndReregisterService(m, srs, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->SPSState = (mDNSu8)(m->SPSSocket != mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SleepProxyServerCallback, mDNSNULL, 0); // Callback, context, flags
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("Sleep Proxy Server %#s %s", srs->RR_SRV.resrec.name->c, m->SPSState ? "started" : "stopped");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Called with lock held
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void mDNSCoreBeSleepProxyServer_internal(mDNS *const m, mDNSu8 sps, mDNSu8 port, mDNSu8 marginalpower, mDNSu8 totpower, mDNSu8 features)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This routine uses mDNS_DeregisterService and calls SleepProxyServerCallback, so we execute in user callback context
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If turning off SPS, close our socket
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // (Do this first, BEFORE calling mDNS_DeregisterService below)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!sps && m->SPSSocket) { mDNSPlatformUDPClose(m->SPSSocket); m->SPSSocket = mDNSNULL; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If turning off, or changing type, deregister old name
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome { m->SPSState = 2; mDNS_DeregisterService_drt(m, &m->SPSRecords, sps ? mDNS_Dereg_rapid : mDNS_Dereg_normal); }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // SPC_DISABLED
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Record our new SPS parameters
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If turning on, open socket and advertise service
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->SPSSocket = mDNSPlatformUDPSocket(m, zeroIPPort);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!m->SPSSocket) { LogMsg("mDNSCoreBeSleepProxyServer: Failed to allocate SPSSocket"); goto fail; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->SPSState == 0) SleepProxyServerCallback(m, &m->SPSRecords, mStatus_MemFree);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // SPC_DISABLED
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("mDNSCoreBeSleepProxyServer turning off from state %d; will wake clients", m->SPSState);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// ***************************************************************************
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSlocal void mDNS_GrowCache_internal(mDNS *const m, CacheEntity *storage, mDNSu32 numrecords)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("Adding cache storage for %d more records (%d bytes)", numrecords, numrecords*sizeof(CacheEntity));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (i=0; i<numrecords; i++) storage[i].next = &storage[i+1];
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSexport void mDNS_GrowCache(mDNS *const m, CacheEntity *storage, mDNSu32 numrecords)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_GrowCache_internal(m, storage, numrecords);
4b22b9337f359bfd063322244f5336cc7c6ffcfarsmDNSexport mStatus mDNS_Init(mDNS *const m, mDNS_PlatformSupport *const p,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheEntity *rrcachestorage, mDNSu32 rrcachesize,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSBool AdvertiseLocalAddresses, mDNSCallback *Callback, void *Context)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->CanReceiveUnicastOn5353 = mDNSfalse; // Assume we can't receive unicasts on 5353, unless platform layer tells us otherwise
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->AdvertiseLocalAddresses = AdvertiseLocalAddresses;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For debugging: To catch and report locking failures
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Task Scheduling variables
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->timenow_adjust = (mDNSs32)mDNSRandom(0xFFFFFFFF);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->timenow = 0; // MUST only be set within mDNS_Lock/mDNS_Unlock section
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NextScheduledResponse = timenow + 0x78000000;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NextScheduledStopTime = timenow + 0x78000000;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->AnnounceOwner = NonZeroTime(timenow + 60 * mDNSPlatformOneSecond);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->NextStatLogTime = m->StatStartTime + kDefaultNextStatsticsLogTime;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // APPLE_OSX_mDNSResponder
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // These fields only required for mDNS Searcher...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (slot = 0; slot < CACHE_HASH_SLOTS; slot++)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->rrcache_nextcheck[slot] = timenow + 0x78000000;;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_GrowCache_internal(m, rrcachestorage, rrcachesize);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Fields below only required for mDNS Responder...
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->FQDN.c[0] = 0;
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // Initialize to 1 for these targets to prevent not joining multicast group for interfaces when
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome // both of these values are zero.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // NAT traversal fields
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->retryIntervalGetAddr = 0; // delta between time sent and retry
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->retryGetAddr = timenow + 0x78000000; // absolute time when we retry
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!m->WCF) { LogMsg("WCFConnectionNew failed"); return -1; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // It's better to do this *after* the platform layer has set up the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // interface list and security credentials
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome uDNS_SetupDNSConfig(m); // Get initial DNS configuration
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void mDNS_ConfigChanged(mDNS *const m)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome DeconstructServiceName(m->SPSRecords.RR_SRV.resrec.name, &name, &type, &domain);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // SPC_DISABLED
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogSPS("Renaming SPS from “%#s” to “%#s”", name.c, newname.c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // When SleepProxyServerCallback gets the mStatus_MemFree message,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // it will reregister the service under the new name
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_DeregisterService_drt(m, &m->SPSRecords, mDNS_Dereg_rapid);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome#endif // SPC_DISABLED
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void DynDNSHostNameCallback(mDNS *const m, AuthRecord *const rr, mStatus result)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (void)m; // unused
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("NameStatusCallback: result %d for registration of name %##s", result, rr->resrec.name->c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformDynDNSHostNameStatusChanged(rr->resrec.name, result);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void PurgeOrReconfirmCacheRecord(mDNS *const m, CacheRecord *cr, const DNSServer * const ptr, mDNSBool lameduck)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSBool purge = cr->resrec.RecordType == kDNSRecordTypePacketNegative ||
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("PurgeOrReconfirmCacheRecord: %s cache record due to %s server %p %#a:%d (%##s): %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome ptr, &ptr->addr, mDNSVal16(ptr->port), ptr->domain.c, CRDisplayString(m, cr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("PurgeorReconfirmCacheRecord: Purging Resourcerecord %s, RecordType %x", CRDisplayString(m, cr), cr->resrec.RecordType);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("PurgeorReconfirmCacheRecord: Reconfirming Resourcerecord %s, RecordType %x", CRDisplayString(m, cr), cr->resrec.RecordType);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Reconfirm_internal(m, cr, kDefaultReconfirmTimeForNoAnswer);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void mDNS_PurgeForQuestion(mDNS *const m, DNSQuestion *q)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheGroup *const cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For DNSSEC questions, purge the corresponding RRSIGs also.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rp = cg ? cg->members : mDNSNULL; rp; rp = rp->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SameNameRecordAnswersQuestion(&rp->resrec, q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNS_PurgeForQuestion: Flushing %s", CRDisplayString(m, rp));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// For DNSSEC question, we need the DNSSEC records also. If the cache does not
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// have the DNSSEC records, we need to re-issue the question with EDNS0/DO bit set.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Just re-issuing the question for RRSIGs does not work in practice as the response
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// may not contain the RRSIGs whose typeCovered field matches the question's qtype.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// For negative responses, we need the NSECs to prove the non-existence. If we don't
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// have the cached NSECs, purge them. For positive responses, if we don't have the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// RRSIGs and if we have not already issued the question with EDNS0/DO bit set, purge
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void CheckForDNSSECRecords(mDNS *const m, DNSQuestion *q)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheGroup *const cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rp = cg ? cg->members : mDNSNULL; rp; rp = rp->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (SameNameRecordAnswersQuestion(&rp->resrec, q))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rp->resrec.RecordType != kDNSRecordTypePacketNegative || !rp->nsec)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("CheckForDNSSECRecords: Flushing %s", CRDisplayString(m, rp));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome// Check for a positive unicast response to the question but with qtype
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport mDNSBool mDNS_CheckForCacheRecord(mDNS *const m, DNSQuestion *q, mDNSu16 qtype)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome CacheGroup *const cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Create an identical question but with qtype
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetupQuestion(&question, q->InterfaceID, &q->qname, qtype, mDNSNULL, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rp = cg ? cg->members : mDNSNULL; rp; rp = rp->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!rp->resrec.InterfaceID && rp->resrec.RecordType != kDNSRecordTypePacketNegative &&
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome SameNameRecordAnswersQuestion(&rp->resrec, &question))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNS_CheckForCacheRecord: Found %s", CRDisplayString(m, rp));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void DNSServerChangeForQuestion(mDNS *const m, DNSQuestion *q, DNSServer *new)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("DNSServerChangeForQuestion: ERROR: Called for duplicate question %##s", q->qname.c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Make sure all the duplicate questions point to the same DNSServer so that delivery
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // of events for all of them are consistent. Duplicates for a question are always inserted
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // after in the list.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (qptr->DuplicateOf == q) { qptr->validDNSServers = q->validDNSServers; qptr->qDNSServer = new; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void SetConfigState(mDNS *const m, mDNSBool delete)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (ptr = m->DNSServers; ptr; ptr = ptr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We handle the mcast resolvers here itself as mDNSPlatformSetDNSConfig looks at
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // mcast resolvers. Today we get both mcast and ucast configuration using the same
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (mr = m->McastResolvers; mr; mr = mr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (ptr = m->DNSServers; ptr; ptr = ptr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (mr = m->McastResolvers; mr; mr = mr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport mStatus uDNS_SetupDNSConfig(mDNS *const m)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome McastResolver *mr, **mres = &m->McastResolvers;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Let the platform layer get the current DNS information and setup the WAB queries if needed.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We need to first mark all the entries to be deleted. If the configuration changed, then
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the entries would be undeleted appropriately. Otherwise, we need to clear them.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: The last argument to mDNSPlatformSetDNSConfig is "mDNStrue" which means ack the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // configuration. We already processed search domains in uDNS_SetupWABQueries above and
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // hence we are ready to ack the configuration as this is the last call to mDNSPlatformSetConfig
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // for the dns configuration change notification.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (!mDNSPlatformSetDNSConfig(m, mDNStrue, mDNSfalse, &fqdn, mDNSNULL, mDNSNULL, mDNStrue))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("uDNS_SetupDNSConfig: No configuration change");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For now, we just delete the mcast resolvers. We don't deal with cache or
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // questions here. Neither question nor cache point to mcast resolvers. Questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // do inherit the timeout values from mcast resolvers. But we don't bother
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // affecting them as they never change.
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome if (((*mres)->flags & McastResolver_FlagDelete) != 0)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("uDNS_SetupDNSConfig: Deleting mcast resolver %##s", mr, mr->domain.c);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Update our qDNSServer pointers before we go and free the DNSServer object memory
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // All non-scoped resolvers share the same resGroupID. At no point in time a cache entry using DNSServer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // from scoped resolver will be used to answer non-scoped questions and vice versa, as scoped and non-scoped
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // resolvers don't share the same resGroupID. A few examples to describe the interaction with how we pick
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // DNSServers and flush the cache.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // - A non-scoped question picks DNSServer X, creates a cache entry with X. If a new resolver gets added later that
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // is a better match, we pick the new DNSServer for the question and activate the unicast query. We may or may not
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // flush the cache (See PurgeOrReconfirmCacheRecord). In either case, we don't change the cache record's DNSServer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // pointer immediately (qDNSServer and rDNSServer may be different but still share the same resGroupID). If we don't
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // flush the cache immediately, the record's rDNSServer pointer will be updated (in mDNSCoreReceiveResponse)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // later when we get the response. If we purge the cache, we still deliver a RMV when it is purged even though
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we don't update the cache record's DNSServer pointer to match the question's DNSSever, as they both point to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the same resGroupID.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: If the new DNSServer comes back with a different response than what we have in the cache, we will deliver a RMV
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // of the old followed by ADD of the new records.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // - A non-scoped question picks DNSServer X, creates a cache entry with X. If the resolver gets removed later, we will
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // pick a new DNSServer for the question which may or may not be NULL and set the cache record's pointer to the same
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // as in question's qDNSServer if the cache record is not flushed. If there is no active question, it will be set to NULL.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // - Two questions scoped and non-scoped for the same name will pick two different DNSServer and will end up creating separate
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // cache records and as the resGroupID is different, you can't use the cache record from the scoped DNSServer to answer the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // non-scoped question and vice versa.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (q->DuplicateOf) continue;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If DNS Server for this question has changed, reactivate it
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("uDNS_SetupDNSConfig: Updating DNS Server from %#a:%d (%##s) to %#a:%d (%##s) for question %##s (%s) (scope:%p)",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome t ? &t->addr : mDNSNULL, mDNSVal16(tport), t ? t->domain.c : (mDNSu8*)"",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome s ? &s->addr : mDNSNULL, mDNSVal16(sport), s ? s->domain.c : (mDNSu8*)"",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome q->qname.c, DNSTypeName(q->qtype), q->InterfaceID);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Changing the DNS server affected the SuppressQuery status. We need to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // deliver RMVs for the previous ADDs (if any) before switching to the new
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // DNSServer. To keep it simple, we walk all the questions and mark them
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to be restarted and then handle all of them at once.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we had sent a query out to DNSServer "t" and we are changing to "s", we
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // need to ignore the responses coming back from "t" as the DNS configuration
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // has changed e.g., when a new interface is coming up and that becomes the primary
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // interface, we switch to the DNS servers configured for the primary interface. In
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // this case, we should not accept responses associated with the previous interface as
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the "name" could resolve differently on this new primary interface. Hence, discard
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // in-flight responses.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("uDNS_SetupDNSConfig: Activating query %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // ActivateUnicastQuery is called for duplicate questions also as it does something
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // special for AutoTunnel questions
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (qptr->DuplicateOf == q) ActivateUnicastQuery(m, qptr, mDNStrue);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("uDNS_SetupDNSConfig: Not Updating DNS server question %p %##s (%s) DNS server %#a:%d %p %d",
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome q, q->qname.c, DNSTypeName(q->qtype), t ? &t->addr : mDNSNULL, mDNSVal16(t ? t->port : zp), q->DuplicateOf, q->SuppressUnusable);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (qptr->DuplicateOf == q) { qptr->validDNSServers = q->validDNSServers; qptr->qDNSServer = q->qDNSServer; }
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We already walked the questions and restarted/reactivated them if the dns server
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // change affected the question. That should take care of updating the cache. But
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // what if there is no active question at this point when the DNS server change
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // happened ? There could be old cache entries lying around and if we don't flush
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // them, a new question after the DNS server change could pick up these stale
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // entries and get a wrong answer.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For cache entries that have active questions we might have skipped rescheduling
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the questions if they were suppressed (see above). To keep it simple, we walk
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // all the cache entries to make sure that there are no stale entries. We use the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // active question's InterfaceID/ServiceID for looking up the right DNS server.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note that the unscoped value for ServiceID is -1.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Note: If GetServerForName returns NULL, it could either mean that there are no
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // DNS servers or no matching DNS servers for this question. In either case,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // the cache should get purged below when we process deleted DNS servers.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (cr->CRActiveQuestion ? cr->CRActiveQuestion->InterfaceID : mDNSNULL),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (cr->CRActiveQuestion ? cr->CRActiveQuestion->ServiceID : -1));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Purge or Reconfirm if this cache entry would use the new DNS server
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // As the DNSServers for this cache record is not the same anymore, we don't
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // want any new questions to pick this old value. If there is no active question,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we can't possibly re-confirm, so purge in that case. If it is a DNSSEC question,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // purge the cache as the DNSSEC capabilities of the DNS server may have changed.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (cr->CRActiveQuestion == mDNSNULL || DNSSECQuestion(cr->CRActiveQuestion))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("uDNS_SetupDNSConfig: Purging Resourcerecord %s, New DNS server %#a , Old DNS server %#a", CRDisplayString(m, cr),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome &ptr->addr, (cr->resrec.rDNSServer != mDNSNULL ? &cr->resrec.rDNSServer->addr : mDNSNULL));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("uDNS_SetupDNSConfig: Purging/Reconfirming Resourcerecord %s, New DNS server %#a, Old DNS server %#a", CRDisplayString(m, cr),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome &ptr->addr, (cr->resrec.rDNSServer != mDNSNULL ? &cr->resrec.rDNSServer->addr : mDNSNULL));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome PurgeOrReconfirmCacheRecord(m, cr, ptr, mDNSfalse);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Scan our cache, looking for uDNS records that we would have queried this server for.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We reconfirm any records that match, because in this world of split DNS, firewalls, etc.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // different DNS servers can give different answers to the same question.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we don't have an active question for this cache record, neither Purge can
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // generate RMV events nor Reconfirm can send queries out. Just set the DNSServer
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // pointer on the record NULL so that we don't point to freed memory (We might dereference
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // DNSServer pointers from resource record for logging purposes).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If there is an active question, point to its DNSServer as long as it does not point to the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // freed one. We already went through the questions above and made them point at either the
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // new server or NULL if there is no server.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("uDNS_SetupDNSConfig: ERROR!! Cache Record %s Active question %##s (%s) (scope:%p) poining to DNSServer Address %#a"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome " to be freed", CRDisplayString(m, cr), qptr->qname.c, DNSTypeName(qptr->qtype), qptr->InterfaceID, &ptr->addr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("uDNS_SetupDNSConfig: Cache Record %s, Active question %##s (%s) (scope:%p), pointing to DNSServer %#a (to be deleted),"
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome " resetting to question's DNSServer Address %#a", CRDisplayString(m, cr), qptr->qname.c, DNSTypeName(qptr->qtype),
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome qptr->InterfaceID, &ptr->addr, (qptr->qDNSServer ? &qptr->qDNSServer->addr : mDNSNULL));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("uDNS_SetupDNSConfig: Cache Record %##s has no Active question, Record's DNSServer Address %#a, Server to be deleted %#a",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome cr->resrec.name, &cr->resrec.rDNSServer->addr, &ptr->addr);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome PurgeOrReconfirmCacheRecord(m, cr, ptr, mDNStrue);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("uDNS_SetupDNSConfig: Deleting server %p %#a:%d (%##s) %d", ptr, &ptr->addr, mDNSVal16(ptr->port), ptr->domain.c, NumUnicastDNSServers);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we now have no DNS servers at all and we used to have some, then immediately purge all unicast cache records (including for LLQs).
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This is important for giving prompt remove events when the user disconnects the Ethernet cable or turns off wireless.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Otherwise, stale data lingers for 5-10 seconds, which is not the user-experience people expect from Bonjour.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Similarly, if we now have some DNS servers and we used to have none, we want to purge any fake negative results we may have generated.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if ((m->DNSServers != mDNSNULL) != (oldServers != mDNSNULL))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("uDNS_SetupDNSConfig: %s available; purged %d unicast DNS records from cache",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->DNSServers ? "DNS server became" : "No DNS servers", count);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Force anything that needs to get zone data to get that information again
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Did our FQDN change?
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->FQDN.c[0]) mDNS_RemoveDynDNSHostName(m, &m->FQDN);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->FQDN.c[0])
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSPlatformDynDNSHostNameStatusChanged(&m->FQDN, 1);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_AddDynDNSHostName(m, &m->FQDN, DynDNSHostNameCallback, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // handle router and primary interface changes
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (mDNSPlatformGetPrimaryInterface(m, &v4, &v6, &r) == mStatus_NoError && !mDNSv4AddressIsLinkLocal(&v4.ip.v4))
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome !mDNSIPv4AddressIsZero(v4.ip.v4) ? &v4 : mDNSNULL,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome !mDNSIPv6AddressIsZero(v6.ip.v6) ? &v6 : mDNSNULL,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome !mDNSIPv4AddressIsZero(r.ip.v4) ? &r : mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_SetPrimaryInterfaceInfo(m, mDNSNULL, mDNSNULL, mDNSNULL);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->FQDN.c[0]) mDNSPlatformDynDNSHostNameStatusChanged(&m->FQDN, 1); // Set status to 1 to indicate temporary failure
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome debugf("uDNS_SetupDNSConfig: number of unicast DNS servers %d", NumUnicastDNSServers);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSexport void mDNSCoreInitComplete(mDNS *const m, mStatus result)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas SoomemDNSlocal void DeregLoop(mDNS *const m, AuthRecord *const start)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("DeregLoop: %s deregistration for %p %02X %s",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome (rr->resrec.RecordType != kDNSRecordTypeDeregistering) ? "Initiating " : "Accelerating",
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr, rr->resrec.RecordType, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (rr->resrec.RecordType != kDNSRecordTypeDeregistering)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Deregister_internal(m, rr, mDNS_Dereg_rapid);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome rr->LastAPTime = m->timenow - rr->ThisAPInterval;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Mustn't advance m->CurrentRecord until *after* mDNS_Deregister_internal, because
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // new records could have been added to the end of the list as a result of that call.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome m->ShutdownTime = NonZeroTime(m->timenow + mDNSPlatformOneSecond * 5);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNSCoreBeSleepProxyServer_internal(m, 0, 0, 0, 0, 0);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->WCF) WCFConnectionDealloc((WCFConnection *)m->WCF);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Don't need to do SleepRecordRegistrations() here
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // because we deregister all records and services later in this routine
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome while (m->Hostnames) mDNS_RemoveDynDNSHostName(m, &m->Hostnames->fqdn);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // For each member of our SearchList, deregister any records it may have created, and cut them from the list.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Otherwise they'll be forcibly deregistered for us (without being cut them from the appropriate list)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // and we may crash because the list still contains dangling pointers.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_Deregister_internal(m, &dereg->ar, mDNS_Dereg_normal); // Memory will be freed in the FreeARElemCallback
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Shut down all our active NAT Traversals
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome mDNS_StopNATOperation_internal(m, t); // This will cut 't' from the list, thereby advancing m->NATTraversals in the process
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // After stopping the NAT Traversal, we zero out the fields.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // This has particularly important implications for our AutoTunnel records --
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // when we deregister our AutoTunnel records below, we don't want their mStatus_MemFree
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // handlers to just turn around and attempt to re-register those same records.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Clearing t->ExternalPort/t->RequestedPort will cause the mStatus_MemFree callback handlers
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // to not do this.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Make sure there are nothing but deregistering records remaining in the list
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_StartExit: ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // We're in the process of shutting down, so queries, etc. are no longer available.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // Consequently, determining certain information, e.g. the uDNS update server's IP
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // address, will not be possible. The records on the main list are more likely to
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // already contain such information, so we deregister the duplicate records first.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNS_StartExit: Deregistering duplicate resource records");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogInfo("mDNS_StartExit: Deregistering resource records");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If we scheduled a response to send goodbye packets, we set NextScheduledResponse to now. Normally when deregistering records,
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // we allow up to 100ms delay (to help improve record grouping) but when shutting down we don't want any such delay.
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->NextScheduledResponse - m->timenow < mDNSPlatformOneSecond)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->ResourceRecords) LogInfo("mDNS_StartExit: Sending final record deregistrations");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome else LogInfo("mDNS_StartExit: No deregistering records remain");
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = m->DuplicateRecords; rr; rr = rr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_StartExit: Should not still have Duplicate Records remaining: %02X %s", rr->resrec.RecordType, ARDisplayString(m, rr));
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome // If any deregistering records remain, send their deregistration announcements before we exit
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome if (m->mDNSPlatformStatus != mStatus_NoError) DiscardDeregistrations(m);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome mDNSu32 rrcache_totalused = m->rrcache_totalused;
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (slot = 0; slot < CACHE_HASH_SLOTS; slot++)
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome debugf("mDNS_FinalExit: RR Cache was using %ld records, %lu active", rrcache_totalused, rrcache_active);
cda73f64f20b8a0afc4909f5ea1f055ec7913856Toomas Soome LogMsg("*** ERROR *** rrcache_totalused %lu; rrcache_active %lu != m->rrcache_active %lu", rrcache_totalused, rrcache_active, m->rrcache_active);
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome for (rr = m->ResourceRecords; rr; rr = rr->next)
5ffb0c9b03b5149ff4f5821a62be4a52408ada2aToomas Soome LogMsg("mDNS_FinalExit failed to send goodbye for: %p %02X %s", rr, rr->resrec.RecordType, ARDisplayString(m, rr));