DNSCommon.h revision 4b22b9337f359bfd063322244f5336cc7c6ffcfa
/* -*- Mode: C; tab-width: 4 -*-
*
* Copyright (c) 2002-2003 Apple Computer, Inc. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
Change History (most recent first):
$Log: DNSCommon.h,v $
Revision 1.34.2.1 2006/08/29 06:24:22 cheshire
Re-licensed mDNSResponder daemon source code under Apache License, Version 2.0
Revision 1.34 2006/03/18 21:47:56 cheshire
<rdar://problem/4073825> Improve logic for delaying packets after repeated interface transitions
Revision 1.33 2006/03/10 21:51:41 cheshire
<rdar://problem/4111464> After record update, old record sometimes remains in cache
Split out SameRDataBody() into a separate routine so it can be called from other code
Revision 1.32 2005/03/21 00:33:51 shersche
<rdar://problem/4021486> Fix build warnings on Win32 platform
Revision 1.31 2005/02/18 00:43:11 cheshire
<rdar://problem/4010245> mDNSResponder should auto-truncate service names that are too long
Revision 1.30 2005/01/19 03:12:44 cheshire
Move LocalRecordReady() macro from mDNS.c to DNSCommon.h
Revision 1.29 2004/12/15 02:11:22 ksekar
<rdar://problem/3917317> Don't check for Dynamic DNS hostname uniqueness
Revision 1.28 2004/12/06 21:15:22 ksekar
<rdar://problem/3884386> mDNSResponder crashed in CheckServiceRegistrations
Revision 1.27 2004/12/03 07:20:50 ksekar
<rdar://problem/3674208> Wide-Area: Registration of large TXT record fails
Revision 1.26 2004/12/03 05:18:33 ksekar
<rdar://problem/3810596> mDNSResponder needs to return more specific TSIG errors
Revision 1.25 2004/10/26 03:52:02 cheshire
Update checkin comments
Revision 1.24 2004/10/23 01:16:00 cheshire
<rdar://problem/3851677> uDNS operations not always reliable on multi-homed hosts
Revision 1.23 2004/10/03 23:18:58 cheshire
Move address comparison macros from DNSCommon.h to mDNSEmbeddedAPI.h
Revision 1.22 2004/09/30 00:24:56 ksekar
<rdar://problem/3695802> Dynamically update default registration domains on config change
Revision 1.21 2004/09/17 01:08:48 cheshire
Renamed mDNSClientAPI.h to mDNSEmbeddedAPI.h
The name "mDNSClientAPI.h" is misleading to new developers looking at this code. The interfaces
declared in that file are ONLY appropriate to single-address-space embedded applications.
For clients on general-purpose computers, the interfaces defined in dns_sd.h should be used.
Revision 1.20 2004/09/17 00:49:51 cheshire
Get rid of now-unused GetResourceRecord -- the correct (safe) routine to use
is GetLargeResourceRecord
Revision 1.19 2004/09/16 21:59:15 cheshire
For consistency with zerov6Addr, rename zeroIPAddr to zerov4Addr
Revision 1.18 2004/09/16 02:29:39 cheshire
Moved mDNS_Lock/mDNS_Unlock to DNSCommon.c; Added necessary locking around
uDNS_ReceiveMsg, uDNS_StartQuery, uDNS_UpdateRecord, uDNS_RegisterService
Revision 1.17 2004/09/14 23:27:46 cheshire
Fix compile errors
Revision 1.16 2004/08/13 23:46:58 cheshire
"asyncronous" -> "asynchronous"
Revision 1.15 2004/08/10 23:19:14 ksekar
<rdar://problem/3722542>: DNS Extension daemon for Wide Area Service Discovery
Moved routines/constants to allow extern access for garbage collection daemon
Revision 1.14 2004/05/28 23:42:36 ksekar
<rdar://problem/3258021>: Feature: DNS server->client notification on record changes (#7805)
Revision 1.13 2004/05/18 23:51:25 cheshire
Tidy up all checkin comments to use consistent "<rdar://problem/xxxxxxx>" format for bug numbers
Revision 1.12 2004/04/22 04:03:59 cheshire
Headers should use "extern" declarations, not "mDNSexport"
Revision 1.11 2004/04/14 23:09:28 ksekar
Support for TSIG signed dynamic updates.
Revision 1.10 2004/03/13 01:57:33 ksekar
<rdar://problem/3192546>: DynDNS: Dynamic update of service records
Revision 1.9 2004/02/21 08:56:58 bradley
Wrap prototypes with extern "C" for C++ builds.
Revision 1.8 2004/02/06 23:04:18 ksekar
Basic Dynamic Update support via mDNS_Register (dissabled via
UNICAST_REGISTRATION #define)
Revision 1.7 2004/02/03 19:47:36 ksekar
Added an asynchronous state machine mechanism to uDNS.c, including
calls to find the parent zone for a domain name. Changes include code
in repository previously dissabled via "#if 0 incomplete". Codepath
is currently unused, and will be called to create update records, etc.
Revision 1.6 2004/01/27 20:15:22 cheshire
<rdar://problem/3541288>: Time to prune obsolete code for listening on port 53
Revision 1.5 2004/01/24 03:40:56 cheshire
Move mDNSAddrIsDNSMulticast() from DNSCommon.h to mDNSEmbeddedAPI.h so embedded clients can use it
Revision 1.4 2004/01/24 03:38:27 cheshire
Fix minor syntactic error: Headers should use "extern" declarations, not "mDNSexport"
Revision 1.3 2004/01/23 23:23:14 ksekar
Added TCP support for truncated unicast messages.
Revision 1.2 2004/01/21 21:12:23 cheshire
Add missing newline at end of file to make Unix tools happier
Revision 1.1 2003/12/13 03:05:27 ksekar
<rdar://problem/3192548>: DynDNS: Unicast query of service records
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#ifndef __DNSCOMMON_H_
#define __DNSCOMMON_H_
#include "mDNSEmbeddedAPI.h"
#ifdef __cplusplus
extern "C" {
#endif
// ***************************************************************************
#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark - DNS Protocol Constants
#endif
typedef enum
{
kDNSFlag0_QR_Mask = 0x80, // Query or response?
kDNSFlag0_QR_Query = 0x00,
kDNSFlag0_QR_Response = 0x80,
kDNSFlag0_OP_Mask = 0x78, // Operation type
kDNSFlag0_OP_StdQuery = 0x00,
kDNSFlag0_OP_Iquery = 0x08,
kDNSFlag0_OP_Status = 0x10,
kDNSFlag0_OP_Unused3 = 0x18,
kDNSFlag0_OP_Notify = 0x20,
kDNSFlag0_OP_Update = 0x28,
kDNSFlag0_QROP_Mask = kDNSFlag0_QR_Mask | kDNSFlag0_OP_Mask,
kDNSFlag0_AA = 0x04, // Authoritative Answer?
kDNSFlag0_TC = 0x02, // Truncated?
kDNSFlag0_RD = 0x01, // Recursion Desired?
kDNSFlag1_RA = 0x80, // Recursion Available?
kDNSFlag1_Zero = 0x40, // Reserved; must be zero
kDNSFlag1_AD = 0x20, // Authentic Data [RFC 2535]
kDNSFlag1_CD = 0x10, // Checking Disabled [RFC 2535]
kDNSFlag1_RC = 0x0F, // Response code
kDNSFlag1_RC_NoErr = 0x00,
kDNSFlag1_RC_FmtErr = 0x01,
kDNSFlag1_RC_SrvErr = 0x02,
kDNSFlag1_RC_NXDomain = 0x03,
kDNSFlag1_RC_NotImpl = 0x04,
kDNSFlag1_RC_Refused = 0x05,
kDNSFlag1_RC_YXDomain = 0x06,
kDNSFlag1_RC_YXRRSet = 0x07,
kDNSFlag1_RC_NXRRSet = 0x08,
kDNSFlag1_RC_NotAuth = 0x09,
kDNSFlag1_RC_NotZone = 0x0A
} DNS_Flags;
typedef enum
{
TSIG_ErrBadSig = 16,
TSIG_ErrBadKey = 17,
TSIG_ErrBadTime = 18
} TSIG_ErrorCode;
// ***************************************************************************
#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark -
#pragma mark - General Utility Functions
#endif
extern const NetworkInterfaceInfo *GetFirstActiveInterface(const NetworkInterfaceInfo *intf);
extern mDNSInterfaceID GetNextActiveInterfaceID(const NetworkInterfaceInfo *intf);
extern mDNSu32 mDNSRandom(mDNSu32 max);
extern mDNSu32 mDNSRandomFromFixedSeed(mDNSu32 seed, mDNSu32 max);
// ***************************************************************************
#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark -
#pragma mark - Domain Name Utility Functions
#endif
#define mdnsIsDigit(X) ((X) >= '0' && (X) <= '9')
#define mDNSIsUpperCase(X) ((X) >= 'A' && (X) <= 'Z')
#define mDNSIsLowerCase(X) ((X) >= 'a' && (X) <= 'z')
#define mdnsIsLetter(X) (mDNSIsUpperCase(X) || mDNSIsLowerCase(X))
#define mdnsValidHostChar(X, notfirst, notlast) (mdnsIsLetter(X) || mdnsIsDigit(X) || ((notfirst) && (notlast) && (X) == '-') )
extern mDNSu16 CompressedDomainNameLength(const domainname *const name, const domainname *parent);
extern mDNSu32 TruncateUTF8ToLength(mDNSu8 *string, mDNSu32 length, mDNSu32 max);
extern mDNSBool LabelContainsSuffix(const domainlabel *const name, const mDNSBool RichText);
extern mDNSu32 RemoveLabelSuffix(domainlabel *name, mDNSBool RichText);
extern void AppendLabelSuffix(domainlabel *name, mDNSu32 val, mDNSBool RichText);
extern void mDNS_HostNameCallback(mDNS *const m, AuthRecord *const rr, mStatus result);
#define ValidateDomainName(N) (DomainNameLength(N) <= MAX_DOMAIN_NAME)
// ***************************************************************************
#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark -
#pragma mark - Resource Record Utility Functions
#endif
extern mDNSu32 RDataHashValue(mDNSu16 const rdlength, const RDataBody *const rdb);
extern mDNSBool SameRDataBody(const ResourceRecord *const r1, const RDataBody *const r2);
extern mDNSBool SameRData(const ResourceRecord *const r1, const ResourceRecord *const r2);
extern mDNSBool ResourceRecordAnswersQuestion(const ResourceRecord *const rr, const DNSQuestion *const q);
extern mDNSBool SameResourceRecord(ResourceRecord *r1, ResourceRecord *r2);
extern mDNSu16 GetRDLength(const ResourceRecord *const rr, mDNSBool estimate);
#define GetRRDomainNameTarget(RR) ( \
((RR)->rrtype == kDNSType_CNAME || (RR)->rrtype == kDNSType_PTR || (RR)->rrtype == kDNSType_NS) \
? &(RR)->rdata->u.name : \
((RR)->rrtype == kDNSType_SRV ) ? &(RR)->rdata->u.srv.target : mDNSNULL )
extern mDNSBool ValidateRData(const mDNSu16 rrtype, const mDNSu16 rdlength, const RData *const rd);
#define LocalRecordReady(X) ((X)->resrec.RecordType != kDNSRecordTypeUnique && (X)->resrec.RecordType != kDNSRecordTypeDeregistering)
// ***************************************************************************
#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark -
#pragma mark -
#pragma mark - DNS Message Creation Functions
#endif
extern void InitializeDNSMessage(DNSMessageHeader *h, mDNSOpaque16 id, mDNSOpaque16 flags);
extern const mDNSu8 *FindCompressionPointer(const mDNSu8 *const base, const mDNSu8 *const end, const mDNSu8 *const domname);
extern mDNSu8 *putDomainNameAsLabels(const DNSMessage *const msg, mDNSu8 *ptr, const mDNSu8 *const limit, const domainname *const name);
extern mDNSu8 *putRData(const DNSMessage *const msg, mDNSu8 *ptr, const mDNSu8 *const limit, ResourceRecord *rr);
// If we have a single large record to put in the packet, then we allow the packet to be up to 9K bytes,
// but in the normal case we try to keep the packets below 1500 to avoid IP fragmentation on standard Ethernet
extern mDNSu8 *PutResourceRecordTTLWithLimit(DNSMessage *const msg, mDNSu8 *ptr, mDNSu16 *count, ResourceRecord *rr, mDNSu32 ttl, const mDNSu8 *limit);
#define PutResourceRecordTTL(msg, ptr, count, rr, ttl) PutResourceRecordTTLWithLimit((msg), (ptr), (count), (rr), (ttl), \
((msg)->h.numAnswers || (msg)->h.numAuthorities || (msg)->h.numAdditionals) ? (msg)->data + NormalMaxDNSMessageData : (msg)->data + AbsoluteMaxDNSMessageData)
#define PutResourceRecordTTLJumbo(msg, ptr, count, rr, ttl) PutResourceRecordTTLWithLimit((msg), (ptr), (count), (rr), (ttl), \
(msg)->data + AbsoluteMaxDNSMessageData)
extern mDNSu8 *PutResourceRecordCappedTTL(DNSMessage *const msg, mDNSu8 *ptr, mDNSu16 *count, ResourceRecord *rr, mDNSu32 maxttl);
extern mDNSu8 *putEmptyResourceRecord(DNSMessage *const msg, mDNSu8 *ptr, const mDNSu8 *const limit, mDNSu16 *count, const AuthRecord *rr);
extern mDNSu8 *putQuestion(DNSMessage *const msg, mDNSu8 *ptr, const mDNSu8 *const limit, const domainname *const name, mDNSu16 rrtype, mDNSu16 rrclass);
extern mDNSu8 *putZone(DNSMessage *const msg, mDNSu8 *ptr, mDNSu8 *limit, const domainname *zone, mDNSOpaque16 zoneClass);
extern mDNSu8 *putPrereqNameNotInUse(domainname *name, DNSMessage *msg, mDNSu8 *ptr, mDNSu8 *end);
extern mDNSu8 *putDeletionRecord(DNSMessage *msg, mDNSu8 *ptr, ResourceRecord *rr);
extern mDNSu8 *putDeleteRRSet(DNSMessage *msg, mDNSu8 *ptr, const domainname *name, mDNSu16 rrtype);
extern mDNSu8 *putDeleteAllRRSets(DNSMessage *msg, mDNSu8 *ptr, const domainname *name);
extern mDNSu8 *putUpdateLease(DNSMessage *msg, mDNSu8 *end, mDNSu32 lease);
#define PutResourceRecord(MSG, P, C, RR) PutResourceRecordTTL((MSG), (P), (C), (RR), (RR)->rroriginalttl)
// ***************************************************************************
#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark -
#pragma mark - DNS Message Parsing Functions
#endif
extern mDNSu32 DomainNameHashValue(const domainname *const name);
extern void SetNewRData(ResourceRecord *const rr, RData *NewRData, mDNSu16 rdlength);
extern const mDNSu8 *skipDomainName(const DNSMessage *const msg, const mDNSu8 *ptr, const mDNSu8 *const end);
extern const mDNSu8 *getDomainName(const DNSMessage *const msg, const mDNSu8 *ptr, const mDNSu8 *const end,
domainname *const name);
extern const mDNSu8 *skipResourceRecord(const DNSMessage *msg, const mDNSu8 *ptr, const mDNSu8 *end);
extern const mDNSu8 *GetLargeResourceRecord(mDNS *const m, const DNSMessage * const msg, const mDNSu8 *ptr,
const mDNSu8 * end, const mDNSInterfaceID InterfaceID, mDNSu8 RecordType, LargeCacheRecord *largecr);
extern const mDNSu8 *skipQuestion(const DNSMessage *msg, const mDNSu8 *ptr, const mDNSu8 *end);
extern const mDNSu8 *getQuestion(const DNSMessage *msg, const mDNSu8 *ptr, const mDNSu8 *end, const mDNSInterfaceID InterfaceID,
DNSQuestion *question);
extern const mDNSu8 *LocateAnswers(const DNSMessage *const msg, const mDNSu8 *const end);
extern const mDNSu8 *LocateAuthorities(const DNSMessage *const msg, const mDNSu8 *const end);
extern const mDNSu8 *LocateAdditionals(const DNSMessage *const msg, const mDNSu8 *const end);
// ***************************************************************************
#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark -
#pragma mark -
#pragma mark - Packet Sending Functions
#endif
extern mStatus mDNSSendDNSMessage(const mDNS *const m, DNSMessage *const msg, mDNSu8 *end,
mDNSInterfaceID InterfaceID, const mDNSAddr *dst, mDNSIPPort dstport, int sd, uDNS_AuthInfo *authInfo);
// ***************************************************************************
#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark -
#pragma mark - RR List Management & Task Management
#endif
extern void mDNS_Lock(mDNS *const m);
extern void mDNS_Unlock(mDNS *const m);
#ifdef __cplusplus
}
#endif
#endif // __DNSCOMMON_H_