adb.c revision 2a0b8796d46265c078ba7f4dea2979c62ebf5bad
/*
* Copyright (C) 1999 Internet Software Consortium.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
* ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
* CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
* DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
* PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
* ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
* SOFTWARE.
*/
/*
* Implementation notes
* --------------------
*
* In handles, if task == NULL, no events will be generated, and no events
* have been sent. If task != NULL but taskaction == NULL, an event has been
* posted but not yet freed. If neigher are NULL, no event was posted.
*
*/
#include <config.h>
#include <stdio.h>
#include <string.h>
#include <isc/assertions.h>
#include <isc/condition.h>
#include <isc/event.h>
#include <isc/magic.h>
#include <isc/mutex.h>
#include <isc/mutexblock.h>
#include <isc/random.h>
#include <isc/timer.h>
#include <dns/adb.h>
#include <dns/db.h>
#include <dns/events.h>
#include <dns/fixedname.h>
#include <dns/name.h>
#include <dns/rdata.h>
#include <dns/rdataset.h>
#include <dns/resolver.h>
#include <dns/types.h>
#include <dns/view.h>
#include "../isc/util.h"
#if 1
#define DP(x) printf x
#else
#define DP(x)
#endif
#define DNS_ADB_MAGIC 0x44616462 /* Dadb. */
#define DNS_ADB_VALID(x) ISC_MAGIC_VALID(x, DNS_ADB_MAGIC)
#define DNS_ADBNAME_MAGIC 0x6164624e /* adbN. */
#define DNS_ADBNAME_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBNAME_MAGIC)
#define DNS_ADBNAMEHOOK_MAGIC 0x61644e48 /* adNH. */
#define DNS_ADBNAMEHOOK_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBNAMEHOOK_MAGIC)
#define DNS_ADBZONEINFO_MAGIC 0x6164625a /* adbZ. */
#define DNS_ADBZONEINFO_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBZONEINFO_MAGIC)
#define DNS_ADBENTRY_MAGIC 0x61646245 /* adbE. */
#define DNS_ADBENTRY_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBENTRY_MAGIC)
#define DNS_ADBFETCH_MAGIC 0x61644634 /* adF4. */
#define DNS_ADBFETCH_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBFETCH_MAGIC)
/*
* Lengths of lists needs to be powers of two.
*/
#define DNS_ADBNAMELIST_LENGTH 32 /* how many buckets for names */
#define DNS_ADBENTRYLIST_LENGTH 32 /* how many buckets for addresses */
#define CLEAN_SECONDS 20 /* clean this many seconds initially */
#define FREE_ITEMS 16 /* free count for memory pools */
#define FILL_COUNT 8 /* fill count for memory pools */
#define DNS_ADB_INVALIDBUCKET (-1) /* invalid bucket address */
typedef ISC_LIST(dns_adbname_t) dns_adbnamelist_t;
typedef struct dns_adbnamehook dns_adbnamehook_t;
typedef ISC_LIST(dns_adbnamehook_t) dns_adbnamehooklist_t;
typedef struct dns_adbzoneinfo dns_adbzoneinfo_t;
typedef ISC_LIST(dns_adbentry_t) dns_adbentrylist_t;
typedef struct dns_adbfetch dns_adbfetch_t;
struct dns_adb {
unsigned int magic;
isc_mutex_t lock;
isc_mem_t *mctx;
dns_view_t *view;
isc_timermgr_t *timermgr;
isc_timer_t *timer;
isc_taskmgr_t *taskmgr;
isc_task_t *task;
isc_interval_t tick_interval;
unsigned int irefcnt;
unsigned int erefcnt;
isc_mutex_t mplock;
isc_mempool_t *nmp; /* dns_adbname_t */
isc_mempool_t *nhmp; /* dns_adbnamehook_t */
isc_mempool_t *zimp; /* dns_adbzoneinfo_t */
isc_mempool_t *emp; /* dns_adbentry_t */
isc_mempool_t *ahmp; /* dns_adbhandle_t */
isc_mempool_t *aimp; /* dns_adbaddrinfo_t */
isc_mempool_t *afmp; /* dns_adbfetch_t */
isc_random_t rand;
/*
* Bucketized locks and lists for names.
*/
dns_adbnamelist_t names[DNS_ADBNAMELIST_LENGTH];
isc_mutex_t namelocks[DNS_ADBNAMELIST_LENGTH];
isc_boolean_t name_sd[DNS_ADBNAMELIST_LENGTH];
unsigned int name_refcnt[DNS_ADBNAMELIST_LENGTH];
/*
* Bucketized locks for entries.
*/
dns_adbentrylist_t entries[DNS_ADBENTRYLIST_LENGTH];
isc_mutex_t entrylocks[DNS_ADBENTRYLIST_LENGTH];
};
/*
* XXX: This has a pointer to the adb it came from. It shouldn't need
* this, but I can't think of how to get rid of it. In particular, since
* events have but one "arg" value, and that is currently used for the name
* pointer in fetches, we need a way to get to the fetch contexts as well
* as the adb itself.
*/
struct dns_adbname {
unsigned int magic;
dns_name_t name;
dns_adb_t *adb;
unsigned int partial_result;
unsigned int query_pending;
isc_boolean_t dead;
isc_stdtime_t expire_v4;
isc_stdtime_t expire_v6;
int lock_bucket;
dns_adbnamehooklist_t v4;
dns_adbnamehooklist_t v6;
ISC_LIST(dns_adbfetch_t) fetches;
ISC_LIST(dns_adbhandle_t) handles;
ISC_LINK(dns_adbname_t) plink;
};
struct dns_adbfetch {
unsigned int magic;
dns_adbnamehook_t *namehook;
dns_adbentry_t *entry;
dns_fetch_t *fetch;
dns_rdataset_t rdataset;
ISC_LINK(dns_adbfetch_t) plink;
};
/*
* dns_adbnamehook_t
*
* This is a small widget that dangles off a dns_adbname_t. It contains a
* pointer to the address information about this host, and a link to the next
* namehook that will contain the next address this host has.
*/
struct dns_adbnamehook {
unsigned int magic;
dns_adbentry_t *entry;
ISC_LINK(dns_adbnamehook_t) plink;
};
/*
* dns_adbzoneinfo_t
*
* This is a small widget that holds zone-specific information about an
* address. Currently limited to lameness, but could just as easily be
* extended to other types of information about zones.
*/
struct dns_adbzoneinfo {
unsigned int magic;
dns_name_t zone;
isc_stdtime_t lame_timer;
ISC_LINK(dns_adbzoneinfo_t) plink;
};
/*
* An address entry. It holds quite a bit of information about addresses,
* including edns state, rtt, and of course the address of the host.
*/
struct dns_adbentry {
unsigned int magic;
int lock_bucket;
unsigned int refcnt;
unsigned int flags;
int edns_level; /* must be int! */
int goodness; /* bad < 0 <= good */
unsigned int srtt;
isc_sockaddr_t sockaddr;
ISC_LIST(dns_adbzoneinfo_t) zoneinfo;
ISC_LINK(dns_adbentry_t) plink;
};
/*
* Internal functions (and prototypes).
*/
static inline dns_adbname_t *new_adbname(dns_adb_t *, dns_name_t *);
static inline void free_adbname(dns_adb_t *, dns_adbname_t **);
static inline dns_adbnamehook_t *new_adbnamehook(dns_adb_t *,
dns_adbentry_t *);
static inline void free_adbnamehook(dns_adb_t *, dns_adbnamehook_t **);
static inline dns_adbzoneinfo_t *new_adbzoneinfo(dns_adb_t *, dns_name_t *);
static inline void free_adbzoneinfo(dns_adb_t *, dns_adbzoneinfo_t **);
static inline dns_adbentry_t *new_adbentry(dns_adb_t *);
static inline void free_adbentry(dns_adb_t *, dns_adbentry_t **);
static inline dns_adbhandle_t *new_adbhandle(dns_adb_t *);
static inline void free_adbhandle(dns_adb_t *, dns_adbhandle_t **);
static inline dns_adbaddrinfo_t *new_adbaddrinfo(dns_adb_t *,
dns_adbentry_t *);
static inline dns_adbfetch_t *new_adbfetch(dns_adb_t *);
static inline void free_adbfetch(dns_adb_t *, dns_adbfetch_t **);
static inline dns_adbname_t *find_name_and_lock(dns_adb_t *, dns_name_t *,
int *);
static inline dns_adbentry_t *find_entry_and_lock(dns_adb_t *,
isc_sockaddr_t *, int *);
static void dump_adb(dns_adb_t *, FILE *);
static void print_dns_name(FILE *, dns_name_t *);
static void print_namehook_list(FILE *, dns_adbname_t *);
static void print_handle_list(FILE *, dns_adbname_t *);
static void print_fetch_list(FILE *, dns_adbname_t *);
static inline void inc_adb_irefcnt(dns_adb_t *, isc_boolean_t);
static inline void dec_adb_irefcnt(dns_adb_t *, isc_boolean_t);
static inline void inc_adb_erefcnt(dns_adb_t *, isc_boolean_t);
static inline void dec_adb_erefcnt(dns_adb_t *, isc_boolean_t);
static inline void inc_entry_refcnt(dns_adb_t *, dns_adbentry_t *,
isc_boolean_t);
static inline void dec_entry_refcnt(dns_adb_t *, dns_adbentry_t *,
isc_boolean_t);
static inline void violate_locking_hierarchy(isc_mutex_t *, isc_mutex_t *);
static void clean_namehooks(dns_adb_t *, dns_adbnamehooklist_t *);
static void clean_handles_at_name(dns_adbname_t *, isc_eventtype_t);
static void check_expire_namehooks(dns_adbname_t *, isc_stdtime_t);
static void cancel_fetches_at_name(dns_adb_t *, dns_adbname_t *);
static isc_result_t dbfind_name_v4(dns_adbhandle_t *, dns_name_t *,
dns_adbname_t *, int, isc_stdtime_t);
static isc_result_t fetch_name_v4(dns_adbname_t *, isc_stdtime_t now);
static inline void check_exit(dns_adb_t *);
static void timer_cleanup(isc_task_t *, isc_event_t *);
static void destroy(dns_adb_t *);
static void shutdown_names(dns_adb_t *);
static inline void link_name(dns_adb_t *, int, dns_adbname_t *);
static inline void unlink_name(dns_adb_t *, dns_adbname_t *);
static void kill_name(dns_adbname_t **, isc_eventtype_t ev);
#define WANTEVENT(x) (((x) & DNS_ADBFIND_WANTEVENT) != 0)
#define WANTEMPTYEVENT(x) (((x) & DNS_ADBFIND_EMPTYEVENT) != 0)
#define HAVE_INET(n) (!ISC_LIST_EMPTY((n)->v4))
#define HAVE_INET6(n) (!ISC_LIST_EMPTY((n)->v6))
#define HAVE_ADDRS(h) (!ISC_LIST_EMPTY((h)->list))
#define QUERY_INET(x) (((x) & DNS_ADBFIND_INET) != 0)
#define QUERY_INET6(x) (((x) & DNS_ADBFIND_INET6) != 0)
#define QUERYPENDING(x, y) (((x) & (y)) != 0)
#define WANT_INET(x) (((x) & DNS_ADBFIND_INET) != 0)
#define WANT_INET6(x) (((x) & DNS_ADBFIND_INET6) != 0)
#define WANTEDADDR(x, y) (((x) & (y)) != 0)
/*
* Requires the adbname bucket be locked and that no entry buckets be locked.
*/
static isc_result_t
import_rdatasetv4(dns_adbname_t *adbname, dns_rdataset_t *rdataset,
isc_stdtime_t now)
{
isc_result_t result;
dns_adb_t *adb;
dns_adbnamehook_t *nh;
dns_rdata_t rdata;
struct in_addr ina;
isc_sockaddr_t sockaddr;
dns_adbentry_t *foundentry; /* NO CLEAN UP! */
int addr_bucket;
isc_boolean_t new_addresses_added;
INSIST(DNS_ADBNAME_VALID(adbname));
adb = adbname->adb;
INSIST(DNS_ADB_VALID(adb));
addr_bucket = DNS_ADB_INVALIDBUCKET;
new_addresses_added = ISC_FALSE;
result = dns_rdataset_first(rdataset);
while (result == ISC_R_SUCCESS) {
nh = new_adbnamehook(adb, NULL);
if (nh == NULL) {
adbname->partial_result |= DNS_ADBFIND_INET;
result = ISC_R_NOMEMORY;
goto fail;
}
dns_rdataset_current(rdataset, &rdata);
INSIST(rdata.length == 4);
memcpy(&ina.s_addr, rdata.data, 4);
isc_sockaddr_fromin(&sockaddr, &ina, 53);
foundentry = find_entry_and_lock(adb, &sockaddr, &addr_bucket);
if (foundentry == NULL) {
dns_adbentry_t *entry;
entry = new_adbentry(adb);
if (entry == NULL) {
adbname->partial_result |= DNS_ADBFIND_INET;
result = ISC_R_NOMEMORY;
goto fail;
}
entry->sockaddr = sockaddr;
entry->refcnt = 1;
entry->lock_bucket = addr_bucket;
nh->entry = entry;
ISC_LIST_APPEND(adb->entries[addr_bucket],
entry, plink);
} else {
foundentry->refcnt++;
nh->entry = foundentry;
}
new_addresses_added = ISC_TRUE;
ISC_LIST_APPEND(adbname->v4, nh, plink);
nh = NULL;
result = dns_rdataset_next(rdataset);
}
fail:
if (nh != NULL)
free_adbnamehook(adb, &nh);
if (addr_bucket != DNS_ADB_INVALIDBUCKET)
UNLOCK(&adb->entrylocks[addr_bucket]);
if (now + rdataset->ttl < adbname->expire_v4)
adbname->expire_v4 = now + rdataset->ttl;
if (new_addresses_added)
return (ISC_R_SUCCESS); /* XXX lie? */
return (result);
}
/*
* Requires the name's bucket be locked.
*/
static void
kill_name(dns_adbname_t **n, isc_eventtype_t ev)
{
dns_adbname_t *name;
dns_adb_t *adb;
INSIST(n != NULL);
name = *n;
*n = NULL;
INSIST(DNS_ADBNAME_VALID(name));
adb = name->adb;
INSIST(DNS_ADB_VALID(adb));
DP(("killing name %p\n", name));
/*
* If we're dead already, just check to see if we should go
* away now or not.
*/
if (name->dead && ISC_LIST_EMPTY(name->fetches)) {
unlink_name(adb, name);
free_adbname(adb, &name);
return;
}
/*
* Clean up the name's various lists. These two are destructive
* in that they will always empty the list.
*/
clean_handles_at_name(name, ev);
clean_namehooks(adb, &name->v4);
clean_namehooks(adb, &name->v6);
/*
* If fetches are running, cancel them. If none are running, we can
* just kill the name here.
*/
if (ISC_LIST_EMPTY(name->fetches)) {
unlink_name(adb, name);
free_adbname(adb, &name);
} else {
name->dead = ISC_TRUE;
cancel_fetches_at_name(adb, name);
}
}
/*
* Requires the name's bucket be locked and no entry buckets be locked.
*/
static void
check_expire_namehooks(dns_adbname_t *name, isc_stdtime_t now)
{
dns_adb_t *adb;
INSIST(DNS_ADBNAME_VALID(name));
adb = name->adb;
INSIST(DNS_ADB_VALID(adb));
/*
* Check to see if we need to remove the v4 addresses
*/
if (((name->query_pending & DNS_ADBFIND_INET) == 0)
&& (name->expire_v4 < now))
clean_namehooks(adb, &name->v4);
/*
* Check to see if we need to remove the v6 addresses
*/
if (((name->query_pending & DNS_ADBFIND_INET6) == 0)
&& (name->expire_v6 < now))
clean_namehooks(adb, &name->v6);
}
/*
* Requires the name's bucket be locked.
*/
static inline void
link_name(dns_adb_t *adb, int bucket, dns_adbname_t *name)
{
INSIST(name->lock_bucket == DNS_ADB_INVALIDBUCKET);
ISC_LIST_PREPEND(adb->names[bucket], name, plink);
name->lock_bucket = bucket;
adb->name_refcnt[bucket]++;
}
/*
* Requires the name's bucket be locked.
*/
static inline void
unlink_name(dns_adb_t *adb, dns_adbname_t *name)
{
int bucket;
bucket = name->lock_bucket;
INSIST(bucket != DNS_ADB_INVALIDBUCKET);
ISC_LIST_UNLINK(adb->names[bucket], name, plink);
name->lock_bucket = DNS_ADB_INVALIDBUCKET;
INSIST(adb->name_refcnt[bucket] > 0);
adb->name_refcnt[bucket]--;
}
static inline void
violate_locking_hierarchy(isc_mutex_t *have, isc_mutex_t *want)
{
if (isc_mutex_trylock(want) != ISC_R_SUCCESS) {
UNLOCK(have);
LOCK(want);
LOCK(have);
}
}
/*
* The ADB _MUST_ be locked before calling. Also, exit conditions must be
* checked after calling this function.
*/
static void
shutdown_names(dns_adb_t *adb)
{
int bucket;
dns_adbname_t *name;
dns_adbname_t *next_name;
for (bucket = 0 ; bucket < DNS_ADBNAMELIST_LENGTH ; bucket++) {
LOCK(&adb->namelocks[bucket]);
adb->name_sd[bucket] = ISC_TRUE;
/*
* Run through the list. For each name, clean up handles
* found there, and cancel any fetches running. When
* all the fetches are canceled, the name will destroy
* itself.
*/
name = ISC_LIST_HEAD(adb->names[bucket]);
while (name != NULL) {
next_name = ISC_LIST_NEXT(name, plink);
kill_name(&name, DNS_EVENT_ADBSHUTDOWN);
name = next_name;
}
/* kill_name() will decrement the refcnt. */
if (adb->name_refcnt[bucket] == 0)
dec_adb_irefcnt(adb, ISC_FALSE);
UNLOCK(&adb->namelocks[bucket]);
}
dump_adb(adb, stderr);
}
/*
* Name bucket must be locked
*/
static void
cancel_fetches_at_name(dns_adb_t *adb, dns_adbname_t *name)
{
dns_adbfetch_t *fetch;
fetch = ISC_LIST_HEAD(name->fetches);
while (fetch != NULL) {
DP(("Canceling fetch %p for name %p\n", fetch, name));
dns_resolver_cancelfetch(adb->view->resolver, fetch->fetch);
fetch = ISC_LIST_NEXT(fetch, plink);
}
}
/*
* Assumes the name bucket is locked.
*/
static void
clean_namehooks(dns_adb_t *adb, dns_adbnamehooklist_t *namehooks)
{
dns_adbentry_t *entry;
dns_adbnamehook_t *namehook;
int addr_bucket;
addr_bucket = DNS_ADB_INVALIDBUCKET;
namehook = ISC_LIST_HEAD(*namehooks);
while (namehook != NULL) {
INSIST(DNS_ADBNAMEHOOK_VALID(namehook));
/*
* Clean up the entry if needed.
*/
entry = namehook->entry;
if (entry != NULL) {
INSIST(DNS_ADBENTRY_VALID(entry));
if (addr_bucket != entry->lock_bucket) {
if (addr_bucket != DNS_ADB_INVALIDBUCKET)
UNLOCK(&adb->entrylocks[addr_bucket]);
addr_bucket = entry->lock_bucket;
LOCK(&adb->entrylocks[addr_bucket]);
}
dec_entry_refcnt(adb, entry, ISC_FALSE);
}
/*
* Free the namehook
*/
namehook->entry = NULL;
ISC_LIST_UNLINK(*namehooks, namehook, plink);
free_adbnamehook(adb, &namehook);
namehook = ISC_LIST_HEAD(*namehooks);
}
if (addr_bucket != DNS_ADB_INVALIDBUCKET)
UNLOCK(&adb->entrylocks[addr_bucket]);
}
/*
* Assumes the name bucket is locked.
*/
static void
clean_handles_at_name(dns_adbname_t *name, isc_eventtype_t evtype)
{
isc_event_t *ev;
isc_task_t *task;
dns_adbhandle_t *handle;
handle = ISC_LIST_HEAD(name->handles);
while (handle != NULL) {
LOCK(&handle->lock);
/*
* Unlink the handle from the name, letting the caller
* call dns_adb_done() on it to clean it up later.
*/
ISC_LIST_UNLINK(name->handles, handle, plink);
handle->adbname = NULL;
handle->name_bucket = DNS_ADB_INVALIDBUCKET;
ev = &handle->event;
task = ev->sender;
ev->sender = handle;
ev->type = evtype;
DP(("Sending event %p to task %p for handle %p\n",
ev, task, handle));
isc_task_sendanddetach(&task, &ev);
UNLOCK(&handle->lock);
handle = ISC_LIST_HEAD(name->handles);
}
}
static inline void
check_exit(dns_adb_t *adb)
{
if ((adb->irefcnt == 0) && (adb->erefcnt == 0)
&& (isc_mempool_getallocated(adb->ahmp) == 0))
isc_task_shutdown(adb->task);
}
static inline void
inc_adb_irefcnt(dns_adb_t *adb, isc_boolean_t lock)
{
if (lock)
LOCK(&adb->lock);
adb->irefcnt++;
if (lock)
UNLOCK(&adb->lock);
}
static inline void
dec_adb_irefcnt(dns_adb_t *adb, isc_boolean_t lock)
{
if (lock)
LOCK(&adb->lock);
INSIST(adb->irefcnt > 0);
adb->irefcnt--;
check_exit(adb);
if (lock)
UNLOCK(&adb->lock);
}
static inline void
inc_adb_erefcnt(dns_adb_t *adb, isc_boolean_t lock)
{
if (lock)
LOCK(&adb->lock);
adb->erefcnt++;
if (lock)
UNLOCK(&adb->lock);
}
static inline void
dec_adb_erefcnt(dns_adb_t *adb, isc_boolean_t lock)
{
if (lock)
LOCK(&adb->lock);
INSIST(adb->erefcnt > 0);
adb->erefcnt--;
check_exit(adb);
if (lock)
UNLOCK(&adb->lock);
}
static inline void
inc_entry_refcnt(dns_adb_t *adb, dns_adbentry_t *entry, isc_boolean_t lock)
{
int bucket;
bucket = entry->lock_bucket;
if (lock)
LOCK(&adb->entrylocks[bucket]);
entry->refcnt++;
if (lock)
UNLOCK(&adb->entrylocks[bucket]);
}
static inline void
dec_entry_refcnt(dns_adb_t *adb, dns_adbentry_t *entry, isc_boolean_t lock)
{
int bucket;
isc_boolean_t destroy_entry;
bucket = entry->lock_bucket;
if (lock)
LOCK(&adb->entrylocks[bucket]);
INSIST(entry->refcnt > 0);
entry->refcnt--;
destroy_entry = ISC_FALSE;
if (entry->refcnt == 0) {
destroy_entry = ISC_TRUE;
ISC_LIST_UNLINK(adb->entries[bucket], entry, plink);
}
if (lock)
UNLOCK(&adb->entrylocks[bucket]);
if (!destroy_entry)
return;
entry->lock_bucket = DNS_ADB_INVALIDBUCKET;
free_adbentry(adb, &entry);
}
static inline dns_adbname_t *
new_adbname(dns_adb_t *adb, dns_name_t *dnsname)
{
dns_adbname_t *name;
name = isc_mempool_get(adb->nmp);
if (name == NULL)
return (NULL);
dns_name_init(&name->name, NULL);
if (dns_name_dup(dnsname, adb->mctx, &name->name) != ISC_R_SUCCESS) {
isc_mempool_put(adb->nmp, name);
return (NULL);
}
name->magic = DNS_ADBNAME_MAGIC;
name->adb = adb;
name->partial_result = 0;
name->query_pending = 0;
name->dead = ISC_FALSE;
name->expire_v4 = INT_MAX;
name->expire_v6 = INT_MAX;
name->lock_bucket = DNS_ADB_INVALIDBUCKET;
ISC_LIST_INIT(name->v4);
ISC_LIST_INIT(name->v6);
ISC_LIST_INIT(name->fetches);
ISC_LIST_INIT(name->handles);
ISC_LINK_INIT(name, plink);
return (name);
}
static inline void
free_adbname(dns_adb_t *adb, dns_adbname_t **name)
{
dns_adbname_t *n;
INSIST(name != NULL && DNS_ADBNAME_VALID(*name));
n = *name;
*name = NULL;
INSIST(!HAVE_INET(n));
INSIST(ISC_LIST_EMPTY(n->fetches));
INSIST(ISC_LIST_EMPTY(n->handles));
INSIST(!ISC_LINK_LINKED(n, plink));
INSIST(n->lock_bucket == DNS_ADB_INVALIDBUCKET);
INSIST(n->adb == adb);
n->magic = 0;
dns_name_free(&n->name, adb->mctx);
isc_mempool_put(adb->nmp, n);
}
static inline dns_adbnamehook_t *
new_adbnamehook(dns_adb_t *adb, dns_adbentry_t *entry)
{
dns_adbnamehook_t *nh;
nh = isc_mempool_get(adb->nhmp);
if (nh == NULL)
return (NULL);
nh->magic = DNS_ADBNAMEHOOK_MAGIC;
nh->entry = entry;
ISC_LINK_INIT(nh, plink);
return (nh);
}
static inline void
free_adbnamehook(dns_adb_t *adb, dns_adbnamehook_t **namehook)
{
dns_adbnamehook_t *nh;
INSIST(namehook != NULL && DNS_ADBNAMEHOOK_VALID(*namehook));
nh = *namehook;
*namehook = NULL;
INSIST(nh->entry == NULL);
INSIST(!ISC_LINK_LINKED(nh, plink));
nh->magic = 0;
isc_mempool_put(adb->nhmp, nh);
}
static inline dns_adbzoneinfo_t *
new_adbzoneinfo(dns_adb_t *adb, dns_name_t *zone)
{
dns_adbzoneinfo_t *zi;
zi = isc_mempool_get(adb->zimp);
if (zi == NULL)
return (NULL);
dns_name_init(&zi->zone, NULL);
if (dns_name_dup(zone, adb->mctx, &zi->zone) != ISC_R_SUCCESS) {
isc_mempool_put(adb->zimp, zi);
return (NULL);
}
zi->magic = DNS_ADBZONEINFO_MAGIC;
zi->lame_timer = 0;
ISC_LINK_INIT(zi, plink);
return (zi);
}
static inline void
free_adbzoneinfo(dns_adb_t *adb, dns_adbzoneinfo_t **zoneinfo)
{
dns_adbzoneinfo_t *zi;
INSIST(zoneinfo != NULL && DNS_ADBZONEINFO_VALID(*zoneinfo));
zi = *zoneinfo;
*zoneinfo = NULL;
INSIST(!ISC_LINK_LINKED(zi, plink));
dns_name_free(&zi->zone, adb->mctx);
zi->magic = 0;
isc_mempool_put(adb->zimp, zi);
}
static inline dns_adbentry_t *
new_adbentry(dns_adb_t *adb)
{
dns_adbentry_t *e;
isc_uint32_t r;
e = isc_mempool_get(adb->emp);
if (e == NULL)
return (NULL);
e->magic = DNS_ADBENTRY_MAGIC;
e->lock_bucket = DNS_ADB_INVALIDBUCKET;
e->refcnt = 0;
e->flags = 0;
e->goodness = 0;
isc_random_get(&adb->rand, &r);
e->srtt = (r & 0x1f) + 1;
ISC_LIST_INIT(e->zoneinfo);
ISC_LINK_INIT(e, plink);
return (e);
}
static inline void
free_adbentry(dns_adb_t *adb, dns_adbentry_t **entry)
{
dns_adbentry_t *e;
dns_adbzoneinfo_t *zi;
INSIST(entry != NULL && DNS_ADBENTRY_VALID(*entry));
e = *entry;
*entry = NULL;
INSIST(e->lock_bucket == DNS_ADB_INVALIDBUCKET);
INSIST(e->refcnt == 0);
INSIST(!ISC_LINK_LINKED(e, plink));
e->magic = 0;
zi = ISC_LIST_HEAD(e->zoneinfo);
while (zi != NULL) {
ISC_LIST_UNLINK(e->zoneinfo, zi, plink);
free_adbzoneinfo(adb, &zi);
zi = ISC_LIST_HEAD(e->zoneinfo);
}
isc_mempool_put(adb->emp, e);
}
static inline dns_adbhandle_t *
new_adbhandle(dns_adb_t *adb)
{
dns_adbhandle_t *h;
isc_result_t result;
h = isc_mempool_get(adb->ahmp);
if (h == NULL)
return (NULL);
/*
* public members
*/
h->magic = 0;
h->adb = adb;
h->query_pending = 0;
h->partial_result = 0;
h->options = 0;
ISC_LINK_INIT(h, publink);
ISC_LINK_INIT(h, plink);
ISC_LIST_INIT(h->list);
h->name_bucket = DNS_ADB_INVALIDBUCKET;
h->adbname = NULL;
/*
* private members
*/
result = isc_mutex_init(&h->lock);
if (result != ISC_R_SUCCESS) {
UNEXPECTED_ERROR(__FILE__, __LINE__,
"isc_mutex_init failed in new_adbhandle()");
isc_mempool_put(adb->ahmp, h);
return (NULL);
}
ISC_EVENT_INIT(&h->event, sizeof (isc_event_t), 0, 0, 0, NULL, NULL,
NULL, NULL, h);
h->magic = DNS_ADBHANDLE_MAGIC;
return (h);
}
static inline dns_adbfetch_t *
new_adbfetch(dns_adb_t *adb)
{
dns_adbfetch_t *f;
f = isc_mempool_get(adb->afmp);
if (f == NULL)
return (NULL);
f->magic = 0;
f->namehook = NULL;
f->entry = NULL;
f->fetch = NULL;
f->namehook = new_adbnamehook(adb, NULL);
if (f->namehook == NULL)
goto err;
f->entry = new_adbentry(adb);
if (f->entry == NULL)
goto err;
dns_rdataset_init(&f->rdataset);
ISC_LINK_INIT(f, plink);
f->magic = DNS_ADBFETCH_MAGIC;
return (f);
err:
if (f->namehook != NULL)
free_adbnamehook(adb, &f->namehook);
if (f->entry != NULL)
free_adbentry(adb, &f->entry);
isc_mempool_put(adb->afmp, f);
return (NULL);
}
static inline void
free_adbfetch(dns_adb_t *adb, dns_adbfetch_t **fetch)
{
dns_adbfetch_t *f;
INSIST(fetch != NULL && DNS_ADBFETCH_VALID(*fetch));
f = *fetch;
*fetch = NULL;
INSIST(!ISC_LINK_LINKED(f, plink));
f->magic = 0;
if (f->namehook != NULL)
free_adbnamehook(adb, &f->namehook);
if (f->entry != NULL)
free_adbentry(adb, &f->entry);
if (dns_rdataset_isassociated(&f->rdataset))
dns_rdataset_disassociate(&f->rdataset);
isc_mempool_put(adb->afmp, f);
}
static inline void
free_adbhandle(dns_adb_t *adb, dns_adbhandle_t **handlep)
{
dns_adbhandle_t *handle;
INSIST(handlep != NULL && DNS_ADBHANDLE_VALID(*handlep));
handle = *handlep;
*handlep = NULL;
INSIST(!HAVE_ADDRS(handle));
INSIST(!ISC_LINK_LINKED(handle, publink));
INSIST(!ISC_LINK_LINKED(handle, plink));
INSIST(handle->name_bucket == DNS_ADB_INVALIDBUCKET);
INSIST(handle->adbname == NULL);
handle->magic = 0;
isc_mutex_destroy(&handle->lock);
isc_mempool_put(adb->ahmp, handle);
}
/*
* Copy bits from the entry into the newly allocated addrinfo. The entry
* must be locked, and the reference count must be bumped up by one
* if this function returns a valid pointer.
*/
static inline dns_adbaddrinfo_t *
new_adbaddrinfo(dns_adb_t *adb, dns_adbentry_t *entry)
{
dns_adbaddrinfo_t *ai;
ai = isc_mempool_get(adb->aimp);
if (ai == NULL)
return (NULL);
ai->magic = DNS_ADBADDRINFO_MAGIC;
ai->sockaddr = &entry->sockaddr;
ai->goodness = entry->goodness;
ai->srtt = entry->srtt;
ai->flags = entry->flags;
ai->entry = entry;
ISC_LINK_INIT(ai, publink);
return (ai);
}
static inline void
free_adbaddrinfo(dns_adb_t *adb, dns_adbaddrinfo_t **ainfo)
{
dns_adbaddrinfo_t *ai;
INSIST(ainfo != NULL && DNS_ADBADDRINFO_VALID(*ainfo));
ai = *ainfo;
*ainfo = NULL;
INSIST(ai->sockaddr == NULL);
INSIST(ai->entry == NULL);
INSIST(!ISC_LINK_LINKED(ai, publink));
ai->magic = 0;
isc_mempool_put(adb->aimp, ai);
}
/*
* Search for the name. NOTE: The bucket is kept locked on both
* success and failure, so it must always be unlocked by the caller!
*
* On the first call to this function, *bucketp must be set to
* DNS_ADB_INVALIDBUCKET.
*/
static inline dns_adbname_t *
find_name_and_lock(dns_adb_t *adb, dns_name_t *name, int *bucketp)
{
dns_adbname_t *adbname;
int bucket;
bucket = dns_name_hash(name, ISC_FALSE);
bucket &= (DNS_ADBNAMELIST_LENGTH - 1);
if (*bucketp == DNS_ADB_INVALIDBUCKET) {
LOCK(&adb->namelocks[bucket]);
*bucketp = bucket;
} else if (*bucketp != bucket) {
UNLOCK(&adb->namelocks[*bucketp]);
LOCK(&adb->namelocks[bucket]);
*bucketp = bucket;
}
adbname = ISC_LIST_HEAD(adb->names[bucket]);
while (adbname != NULL) {
if (adbname->dead != ISC_TRUE) {
/* XXX should check for expired names here? */
if (dns_name_equal(name, &adbname->name))
return (adbname);
}
adbname = ISC_LIST_NEXT(adbname, plink);
}
return (NULL);
}
/*
* Search for the address. NOTE: The bucket is kept locked on both
* success and failure, so it must always be unlocked by the caller.
*
* On the first call to this function, *bucketp must be set to
* DNS_ADB_INVALIDBUCKET. This will cause a lock to occur. On
* later calls (within the same "lock path") it can be left alone, so
* if this function is called multiple times locking is only done if
* the bucket changes.
*/
static inline dns_adbentry_t *
find_entry_and_lock(dns_adb_t *adb, isc_sockaddr_t *addr, int *bucketp)
{
dns_adbentry_t *entry;
int bucket;
bucket = isc_sockaddr_hash(addr, ISC_TRUE);
bucket &= (DNS_ADBENTRYLIST_LENGTH - 1);
if (*bucketp == DNS_ADB_INVALIDBUCKET) {
LOCK(&adb->entrylocks[bucket]);
*bucketp = bucket;
} else if (*bucketp != bucket) {
UNLOCK(&adb->entrylocks[*bucketp]);
LOCK(&adb->entrylocks[bucket]);
*bucketp = bucket;
}
entry = ISC_LIST_HEAD(adb->entries[bucket]);
while (entry != NULL) {
if (isc_sockaddr_equal(addr, &entry->sockaddr))
return (entry);
entry = ISC_LIST_NEXT(entry, plink);
}
return (NULL);
}
/*
* Entry bucket MUST be locked!
*/
static isc_boolean_t
entry_is_bad_for_zone(dns_adb_t *adb, dns_adbentry_t *entry, dns_name_t *zone,
isc_stdtime_t now)
{
dns_adbzoneinfo_t *zi, *next_zi;
isc_boolean_t is_bad;
is_bad = ISC_FALSE;
zi = ISC_LIST_HEAD(entry->zoneinfo);
if (zi == NULL)
return (ISC_FALSE);
while (zi != NULL) {
next_zi = ISC_LIST_NEXT(zi, plink);
/*
* Has the entry expired?
*/
if (zi->lame_timer < now) {
ISC_LIST_UNLINK(entry->zoneinfo, zi, plink);
free_adbzoneinfo(adb, &zi);
}
/*
* Order tests from least to most expensive.
*/
if (zi != NULL && !is_bad) {
if (dns_name_equal(zone, &zi->zone))
is_bad = ISC_TRUE;
}
zi = next_zi;
}
return (is_bad);
}
static void
copy_namehook_lists(dns_adb_t *adb, dns_adbhandle_t *handle,
dns_adbname_t *name, dns_name_t *zone, isc_stdtime_t now)
{
dns_adbnamehook_t *namehook;
dns_adbaddrinfo_t *addrinfo;
int bucket;
bucket = DNS_ADB_INVALIDBUCKET;
if (handle->options & DNS_ADBFIND_INET) {
namehook = ISC_LIST_HEAD(name->v4);
while (namehook != NULL) {
bucket = namehook->entry->lock_bucket;
LOCK(&adb->entrylocks[bucket]);
if (entry_is_bad_for_zone(adb, namehook->entry,
zone, now))
goto nextv4;
addrinfo = new_adbaddrinfo(adb, namehook->entry);
if (addrinfo == NULL) {
handle->partial_result |= DNS_ADBFIND_INET;
goto out;
}
/*
* Found a valid entry. Add it to the handle's list.
*/
inc_entry_refcnt(adb, namehook->entry, ISC_FALSE);
ISC_LIST_APPEND(handle->list, addrinfo, publink);
addrinfo = NULL;
nextv4:
UNLOCK(&adb->entrylocks[bucket]);
bucket = DNS_ADB_INVALIDBUCKET;
namehook = ISC_LIST_NEXT(namehook, plink);
}
}
if (handle->options & DNS_ADBFIND_INET) {
namehook = ISC_LIST_HEAD(name->v6);
while (namehook != NULL) {
bucket = namehook->entry->lock_bucket;
LOCK(&adb->entrylocks[bucket]);
if (entry_is_bad_for_zone(adb, namehook->entry,
zone, now))
goto nextv6;
addrinfo = new_adbaddrinfo(adb, namehook->entry);
if (addrinfo == NULL) {
handle->partial_result |= DNS_ADBFIND_INET;
goto out;
}
/*
* Found a valid entry. Add it to the handle's list.
*/
inc_entry_refcnt(adb, namehook->entry, ISC_FALSE);
ISC_LIST_APPEND(handle->list, addrinfo, publink);
addrinfo = NULL;
nextv6:
UNLOCK(&adb->entrylocks[bucket]);
bucket = DNS_ADB_INVALIDBUCKET;
namehook = ISC_LIST_NEXT(namehook, plink);
}
}
out:
if (bucket != DNS_ADB_INVALIDBUCKET)
UNLOCK(&adb->entrylocks[bucket]);
}
static void
shutdown_task(isc_task_t *task, isc_event_t *ev)
{
dns_adb_t *adb;
(void)task; /* not used */
adb = ev->arg;
INSIST(DNS_ADB_VALID(adb));
/*
* Kill the timer, and then the ADB itself. Note that this implies
* that this task was the one scheduled to get timer events. If
* this is not true (and it is unfortunate there is no way to INSIST()
* this) baddness will occur.
*/
LOCK(&adb->lock);
isc_timer_detach(&adb->timer);
UNLOCK(&adb->lock);
destroy(adb);
isc_event_free(&ev);
}
/*
* ADB must be locked
*/
static void
cleanup(dns_adb_t *adb)
{
}
static void
timer_cleanup(isc_task_t *task, isc_event_t *ev)
{
dns_adb_t *adb;
isc_result_t result;
(void)task; /* not used */
adb = ev->arg;
INSIST(DNS_ADB_VALID(adb));
LOCK(&adb->lock);
/*
* Call our cleanup routine.
*/
cleanup(adb);
/*
* Reset the timer.
*/
result = isc_timer_reset(adb->timer, isc_timertype_once, NULL,
&adb->tick_interval, ISC_FALSE);
UNLOCK(&adb->lock);
isc_event_free(&ev);
}
static void
destroy(dns_adb_t *adb)
{
adb->magic = 0;
/*
* The timer is already dead, from the task's shutdown callback.
*/
isc_task_detach(&adb->task);
isc_mempool_destroy(&adb->nmp);
isc_mempool_destroy(&adb->nhmp);
isc_mempool_destroy(&adb->zimp);
isc_mempool_destroy(&adb->emp);
isc_mempool_destroy(&adb->ahmp);
isc_mempool_destroy(&adb->aimp);
isc_mempool_destroy(&adb->afmp);
isc_mutexblock_destroy(adb->entrylocks, DNS_ADBENTRYLIST_LENGTH);
isc_mutexblock_destroy(adb->namelocks, DNS_ADBNAMELIST_LENGTH);
isc_mutex_destroy(&adb->lock);
isc_mutex_destroy(&adb->mplock);
isc_random_invalidate(&adb->rand);
isc_mem_put(adb->mctx, adb, sizeof (dns_adb_t));
}
/*
* Public functions.
*/
isc_result_t
dns_adb_create(isc_mem_t *mem, dns_view_t *view, isc_timermgr_t *timermgr,
isc_taskmgr_t *taskmgr, dns_adb_t **newadb)
{
dns_adb_t *adb;
isc_result_t result;
int i;
REQUIRE(mem != NULL);
REQUIRE(view != NULL);
REQUIRE(timermgr != NULL);
REQUIRE(taskmgr != NULL);
REQUIRE(newadb != NULL && *newadb == NULL);
adb = isc_mem_get(mem, sizeof (dns_adb_t));
if (adb == NULL)
return (ISC_R_NOMEMORY);
/*
* Initialize things here that cannot fail, and especially things
* that must be NULL for the error return to work properly.
*/
adb->magic = 0;
adb->erefcnt = 1;
adb->irefcnt = 0;
adb->nmp = NULL;
adb->nhmp = NULL;
adb->zimp = NULL;
adb->emp = NULL;
adb->ahmp = NULL;
adb->aimp = NULL;
adb->afmp = NULL;
adb->task = NULL;
adb->timer = NULL;
adb->mctx = mem;
adb->view = view;
adb->timermgr = timermgr;
adb->taskmgr = taskmgr;
result = isc_random_init(&adb->rand);
if (result != ISC_R_SUCCESS)
goto fail0a;
result = isc_mutex_init(&adb->lock);
if (result != ISC_R_SUCCESS)
goto fail0b;
result = isc_mutex_init(&adb->mplock);
if (result != ISC_R_SUCCESS)
goto fail0c;
/*
* Initialize the bucket locks for names and elements.
* May as well initialize the list heads, too.
*/
result = isc_mutexblock_init(adb->namelocks, DNS_ADBNAMELIST_LENGTH);
if (result != ISC_R_SUCCESS)
goto fail1;
for (i = 0 ; i < DNS_ADBNAMELIST_LENGTH ; i++) {
ISC_LIST_INIT(adb->names[i]);
adb->name_sd[i] = ISC_FALSE;
adb->name_refcnt[i] = 0;
adb->irefcnt++;
}
for (i = 0 ; i < DNS_ADBENTRYLIST_LENGTH ; i++)
ISC_LIST_INIT(adb->entries[i]);
result = isc_mutexblock_init(adb->entrylocks, DNS_ADBENTRYLIST_LENGTH);
if (result != ISC_R_SUCCESS)
goto fail2;
/*
* Memory pools
*/
#define MPINIT(t, p, l, n) do { \
result = isc_mempool_create(mem, sizeof (t), &(p)); \
if (result != ISC_R_SUCCESS) \
goto fail3; \
isc_mempool_setfreemax((p), FREE_ITEMS); \
isc_mempool_setfillcount((p), FILL_COUNT); \
isc_mempool_setname((p), n); \
if (l) \
isc_mempool_associatelock((p), &adb->mplock); \
} while (0)
MPINIT(dns_adbname_t, adb->nmp, ISC_TRUE, "adbname");
MPINIT(dns_adbnamehook_t, adb->nhmp, ISC_TRUE, "adbnamehook");
MPINIT(dns_adbzoneinfo_t, adb->zimp, ISC_TRUE, "adbzoneinfo");
MPINIT(dns_adbentry_t, adb->emp, ISC_TRUE, "adbentry");
MPINIT(dns_adbhandle_t, adb->ahmp, ISC_TRUE, "adbhandle");
MPINIT(dns_adbaddrinfo_t, adb->aimp, ISC_TRUE, "adbaddrinfo");
MPINIT(dns_adbfetch_t, adb->afmp, ISC_TRUE, "adbfetch");
#undef MPINIT
/*
* Allocate a timer and a task for our periodic cleanup.
*/
result = isc_task_create(adb->taskmgr, adb->mctx, 0, &adb->task);
if (result != ISC_R_SUCCESS)
goto fail3;
result = isc_task_onshutdown(adb->task, shutdown_task, adb);
isc_interval_set(&adb->tick_interval, CLEAN_SECONDS, 0);
result = isc_timer_create(adb->timermgr, isc_timertype_once,
NULL, &adb->tick_interval, adb->task,
timer_cleanup, adb, &adb->timer);
if (result != ISC_R_SUCCESS)
goto fail3;
/*
* Normal return.
*/
adb->magic = DNS_ADB_MAGIC;
*newadb = adb;
return (ISC_R_SUCCESS);
fail3:
if (adb->task != NULL)
isc_task_detach(&adb->task);
if (adb->timer != NULL)
isc_timer_detach(&adb->timer);
/* clean up entrylocks */
isc_mutexblock_destroy(adb->entrylocks, DNS_ADBENTRYLIST_LENGTH);
fail2: /* clean up namelocks */
isc_mutexblock_destroy(adb->namelocks, DNS_ADBNAMELIST_LENGTH);
fail1: /* clean up only allocated memory */
if (adb->nmp != NULL)
isc_mempool_destroy(&adb->nmp);
if (adb->nhmp != NULL)
isc_mempool_destroy(&adb->nhmp);
if (adb->zimp != NULL)
isc_mempool_destroy(&adb->zimp);
if (adb->emp != NULL)
isc_mempool_destroy(&adb->emp);
if (adb->ahmp != NULL)
isc_mempool_destroy(&adb->ahmp);
if (adb->aimp != NULL)
isc_mempool_destroy(&adb->aimp);
if (adb->aimp != NULL)
isc_mempool_destroy(&adb->afmp);
isc_mutex_destroy(&adb->mplock);
fail0c:
isc_mutex_destroy(&adb->lock);
fail0b:
isc_random_invalidate(&adb->rand);
fail0a:
isc_mem_put(mem, adb, sizeof (dns_adb_t));
return (result);
}
void
dns_adb_detach(dns_adb_t **adbx)
{
dns_adb_t *adb;
REQUIRE(adbx != NULL && DNS_ADB_VALID(*adbx));
adb = *adbx;
*adbx = NULL;
LOCK(&adb->lock);
dec_adb_erefcnt(adb, ISC_FALSE);
if (adb->erefcnt == 0)
shutdown_names(adb);
check_exit(adb);
UNLOCK(&adb->lock);
}
isc_result_t
dns_adb_lookup(dns_adb_t *adb, isc_task_t *task, isc_taskaction_t action,
void *arg, dns_name_t *name, dns_name_t *zone,
unsigned int options, isc_stdtime_t now,
dns_adbhandle_t **handlep)
{
dns_adbhandle_t *handle;
dns_adbname_t *adbname;
int bucket;
isc_result_t result;
isc_boolean_t attach_to_task;
unsigned int wanted_addresses;
REQUIRE(DNS_ADB_VALID(adb));
if (task != NULL) {
REQUIRE(action != NULL);
}
REQUIRE(name != NULL);
REQUIRE(zone != NULL);
REQUIRE(handlep != NULL && *handlep == NULL);
if ((options & DNS_ADBFIND_WANTEVENT) != 0) {
REQUIRE(task != NULL);
}
attach_to_task = ISC_FALSE;
result = ISC_R_UNEXPECTED;
wanted_addresses = (options & DNS_ADBFIND_ADDRESSMASK);
if (now == 0) {
result = isc_stdtime_get(&now);
if (result != ISC_R_SUCCESS)
return (result);
}
/*
* Look up the name in our internal database.
*
* Possibilities: Note that these are not always exclusive.
*
* No name found. In this case, allocate a new name header and
* an initial namehook or two. If any of these allocations
* fail, clean up and return ISC_R_NOMEMORY.
*
* Name found, valid addresses present. Allocate one addrinfo
* structure for each found and append it to the linked list
* of addresses for this header.
*
* Name found, queries pending. In this case, if a task was
* passed in, allocate a job id, attach it to the name's job
* list and remember to tell the caller that there will be
* more info coming later.
*/
handle = new_adbhandle(adb);
if (handle == NULL)
return (ISC_R_NOMEMORY);
/*
* Remember what types of addresses we are interested in.
*/
handle->options = options;
/*
* Try to see if we know anything about this name at all.
*/
bucket = DNS_ADB_INVALIDBUCKET;
adbname = find_name_and_lock(adb, name, &bucket);
if (adb->name_sd[bucket]) {
DP(("lookup: returning ISC_R_SHUTTINGDOWN\n"));
free_adbhandle(adb, &handle);
result = ISC_R_SHUTTINGDOWN;
goto out;
}
/*
* Nothing found. Allocate a new adbname structure for this name.
*/
if (adbname == NULL) {
adbname = new_adbname(adb, name);
if (adbname == NULL) {
free_adbhandle(adb, &handle);
result = ISC_R_NOMEMORY;
goto out;
}
link_name(adb, bucket, adbname);
}
/*
* Expire old entries, etc.
*/
check_expire_namehooks(adbname, now);
/*
* Try to populate the name from the database and/or
* start fetches.
*/
if (!HAVE_INET(adbname)
&& !QUERY_INET(adbname->query_pending)
&& WANT_INET(wanted_addresses)) {
result = dbfind_name_v4(handle, zone, adbname, bucket, now);
if (result == ISC_R_SUCCESS) {
DP(("lookup: Found v4 for name %p in db\n", adbname));
goto v6;
}
/*
* Try to start fetches for v4.
*/
result = fetch_name_v4(adbname, now);
if (result == ISC_R_SUCCESS) {
DP(("lookup: Started v4 fetch for name %p\n",
adbname));
adbname->query_pending |= DNS_ADBFIND_INET;
goto v6;
}
}
v6:
if (!HAVE_INET6(adbname)
&& !QUERY_INET6(adbname->query_pending)
&& WANT_INET6(wanted_addresses)) {
DP(("XXXMLG IPv6 not supported yet\n"));
}
/*
* Run through the name and copy out the bits we are
* interested in.
*/
copy_namehook_lists(adb, handle, adbname, zone, now);
/*
* Attach to the name's query list if there are queries
* already running, and we have been asked to.
*/
if (WANTEVENT(handle->options)
&& QUERYPENDING(wanted_addresses, adbname->query_pending)
&& (WANTEMPTYEVENT(handle->options) ? HAVE_ADDRS(handle) : 1)) {
handle->adbname = adbname;
handle->name_bucket = bucket;
ISC_LIST_APPEND(adbname->handles, handle, plink);
attach_to_task = ISC_TRUE;
handle->query_pending = (adbname->query_pending
& wanted_addresses);
} else {
handle->options &= ~DNS_ADBFIND_WANTEVENT;
}
handle->partial_result |= (adbname->partial_result & wanted_addresses);
result = ISC_R_SUCCESS;
out:
if (handle != NULL) {
*handlep = handle;
if (attach_to_task) {
isc_task_t *taskp;
taskp = NULL;
isc_task_attach(task, &taskp);
handle->event.sender = taskp;
handle->event.action = action;
handle->event.arg = arg;
}
}
if (bucket != DNS_ADB_INVALIDBUCKET)
UNLOCK(&adb->namelocks[bucket]);
return (result);
}
isc_result_t
dns_adb_deletename(dns_adb_t *adb, dns_name_t *host)
{
int name_bucket;
dns_adbname_t *name;
isc_boolean_t decr_adbrefcnt;
REQUIRE(DNS_ADB_VALID(adb));
REQUIRE(host != NULL);
name = NULL;
/*
* Find the name.
*/
name_bucket = DNS_ADB_INVALIDBUCKET;
name = find_name_and_lock(adb, host, &name_bucket);
if (name == NULL) {
UNLOCK(&adb->namelocks[name_bucket]);
return (ISC_R_NOTFOUND);
}
kill_name(&name, DNS_EVENT_ADBNAMEDELETED);
decr_adbrefcnt = ISC_FALSE;
if (adb->name_sd[name_bucket] && (adb->name_refcnt[name_bucket] == 0))
decr_adbrefcnt = ISC_TRUE;
if (name_bucket != DNS_ADB_INVALIDBUCKET)
UNLOCK(&adb->namelocks[name_bucket]);
if (decr_adbrefcnt)
dec_adb_irefcnt(adb, ISC_TRUE);
return (DNS_R_SUCCESS);
}
isc_result_t
dns_adb_insert(dns_adb_t *adb, dns_name_t *host, isc_sockaddr_t *addr,
dns_ttl_t ttl, isc_stdtime_t now)
{
dns_adbname_t *name;
isc_boolean_t free_name;
dns_adbentry_t *entry;
isc_boolean_t free_entry;
dns_adbnamehook_t *namehook;
isc_boolean_t free_namehook;
int name_bucket, addr_bucket; /* unlock if != DNS_ADB_INVALIDBUCKET */
isc_result_t result;
isc_stdtime_t expire_time;
REQUIRE(DNS_ADB_VALID(adb));
REQUIRE(host != NULL);
REQUIRE(addr != NULL);
if (now == 0) {
result = isc_stdtime_get(&now);
if (result != ISC_R_SUCCESS)
return (result);
}
expire_time = now + ttl;
name = NULL;
free_name = ISC_FALSE;
entry = NULL;
free_entry = ISC_FALSE;
namehook = NULL;
free_namehook = ISC_FALSE;
result = ISC_R_UNEXPECTED;
/*
* First, see if the host is already in the database. If it is,
* don't make a new host entry. If not, copy the name and name's
* contents into our structure and allocate what we'll need
* to attach things together.
*/
name_bucket = DNS_ADB_INVALIDBUCKET;
name = find_name_and_lock(adb, host, &name_bucket);
if (name == NULL) {
name = new_adbname(adb, host);
if (name == NULL) {
result = ISC_R_NOMEMORY;
goto out;
}
free_name = ISC_TRUE;
name->expire_v4 = expire_time;
}
/*
* Now, while keeping the name locked, search for the address.
* Three possibilities: One, the address doesn't exist.
* Two, the address exists, but we aren't linked to it.
* Three, the address exists and we are linked to it.
* (1) causes a new entry and namehook to be created.
* (2) causes only a new namehook.
* (3) is an error.
*/
addr_bucket = DNS_ADB_INVALIDBUCKET;
entry = find_entry_and_lock(adb, addr, &addr_bucket);
/*
* Case (1): new entry and namehook.
*/
if (entry == NULL) {
entry = new_adbentry(adb);
if (entry == NULL) {
result = ISC_R_NOMEMORY;
goto out;
}
free_entry = ISC_TRUE;
}
/*
* Case (3): entry exists, we're linked.
*/
namehook = ISC_LIST_HEAD(name->v4);
while (namehook != NULL) {
if (namehook->entry == entry) {
result = ISC_R_EXISTS;
goto out;
}
namehook = ISC_LIST_NEXT(namehook, plink);
}
/*
* Case (2): New namehook, link to entry from above.
*/
namehook = new_adbnamehook(adb, entry);
if (namehook == NULL) {
result = ISC_R_NOMEMORY;
goto out;
}
free_namehook = ISC_TRUE;
ISC_LIST_APPEND(name->v4, namehook, plink);
entry->lock_bucket = addr_bucket;
inc_entry_refcnt(adb, entry, ISC_FALSE);
entry->sockaddr = *addr;
/*
* If needed, string up the name and entry.
*/
if (!ISC_LINK_LINKED(name, plink))
link_name(adb, name_bucket, name);
if (!ISC_LINK_LINKED(entry, plink))
ISC_LIST_PREPEND(adb->entries[addr_bucket], entry, plink);
if (name->expire_v4 > expire_time)
name->expire_v4 = expire_time;
UNLOCK(&adb->namelocks[name_bucket]);
name_bucket = DNS_ADB_INVALIDBUCKET;
UNLOCK(&adb->entrylocks[addr_bucket]);
addr_bucket = DNS_ADB_INVALIDBUCKET;
return (ISC_R_SUCCESS);
out:
if (free_name)
free_adbname(adb, &name);
if (free_entry)
isc_mempool_put(adb->emp, entry);
if (free_namehook)
isc_mempool_put(adb->nhmp, namehook);
if (name_bucket != DNS_ADB_INVALIDBUCKET)
UNLOCK(&adb->namelocks[name_bucket]);
if (addr_bucket != DNS_ADB_INVALIDBUCKET)
UNLOCK(&adb->entrylocks[addr_bucket]);
return (result);
}
void
dns_adb_done(dns_adbhandle_t **handlep)
{
dns_adbhandle_t *handle;
dns_adbentry_t *entry;
dns_adbaddrinfo_t *ai;
int bucket;
dns_adb_t *adb;
REQUIRE(handlep != NULL && DNS_ADBHANDLE_VALID(*handlep));
handle = *handlep;
*handlep = NULL;
LOCK(&handle->lock);
DP(("dns_adb_done on handle %p\n", handle));
adb = handle->adb;
REQUIRE(DNS_ADB_VALID(adb));
bucket = handle->name_bucket;
if (bucket == DNS_ADB_INVALIDBUCKET)
goto cleanup;
/*
* We need to get the adbname's lock to unlink the handle.
*/
violate_locking_hierarchy(&handle->lock, &adb->namelocks[bucket]);
bucket = handle->name_bucket;
if (bucket != DNS_ADB_INVALIDBUCKET) {
ISC_LIST_UNLINK(handle->adbname->handles, handle, plink);
handle->adbname = NULL;
handle->name_bucket = DNS_ADB_INVALIDBUCKET;
}
UNLOCK(&adb->namelocks[bucket]);
bucket = DNS_ADB_INVALIDBUCKET;
cleanup:
UNLOCK(&handle->lock);
/*
* The handle doesn't exist on any list, and nothing is locked.
* Return the handle to the memory pool, and decrement the adb's
* reference count.
*/
ai = ISC_LIST_HEAD(handle->list);
while (ai != NULL) {
ISC_LIST_UNLINK(handle->list, ai, publink);
entry = ai->entry;
ai->entry = NULL;
ai->sockaddr = NULL;
INSIST(DNS_ADBENTRY_VALID(entry));
dec_entry_refcnt(adb, entry, ISC_TRUE);
free_adbaddrinfo(adb, &ai);
ai = ISC_LIST_HEAD(handle->list);
}
LOCK(&adb->lock);
free_adbhandle(adb, &handle);
check_exit(adb);
UNLOCK(&adb->lock);
}
void
dns_adb_dump(dns_adb_t *adb, FILE *f)
{
REQUIRE(DNS_ADB_VALID(adb));
REQUIRE(f != NULL);
/*
* Lock the adb itself, lock all the name buckets, then lock all
* the entry buckets. This should put the adb into a state where
* nothing can change, so we can iterate through everything and
* print at our leasure.
*/
LOCK(&adb->lock);
dump_adb(adb, f);
UNLOCK(&adb->lock);
}
static void
dump_adb(dns_adb_t *adb, FILE *f)
{
int i;
isc_sockaddr_t *sa;
dns_adbname_t *name;
dns_adbentry_t *entry;
char tmp[512];
const char *tmpp;
fprintf(f, "ADB %p DUMP:\n", adb);
fprintf(f, "erefcnt %u, irefcnt %u, handles out %u\n",
adb->erefcnt, adb->irefcnt,
isc_mempool_getallocated(adb->nhmp));
for (i = 0 ; i < DNS_ADBNAMELIST_LENGTH ; i++)
LOCK(&adb->namelocks[i]);
for (i = 0 ; i < DNS_ADBENTRYLIST_LENGTH ; i++)
LOCK(&adb->entrylocks[i]);
/*
* Dump the names
*/
fprintf(f, "Names:\n");
for (i = 0 ; i < DNS_ADBNAMELIST_LENGTH ; i++) {
name = ISC_LIST_HEAD(adb->names[i]);
if (name == NULL)
continue;
fprintf(f, "Name bucket %d:\n", i);
while (name != NULL) {
fprintf(f, "name %p\n", name);
if (!DNS_ADBNAME_VALID(name))
fprintf(f, "\tMAGIC %08x\n", name->magic);
fprintf(f, "\texpiry [%u %u] ",
name->expire_v4, name->expire_v6);
print_dns_name(f, &name->name);
fprintf(f, "\n");
print_namehook_list(f, name);
print_fetch_list(f, name);
print_handle_list(f, name);
fprintf(f, "\n");
name = ISC_LIST_NEXT(name, plink);
}
}
/*
* Dump the entries
*/
fprintf(f, "Entries:\n");
for (i = 0 ; i < DNS_ADBENTRYLIST_LENGTH ; i++) {
entry = ISC_LIST_HEAD(adb->entries[i]);
if (entry == NULL)
continue;
fprintf(f, "Entry bucket %d:\n", i);
while (entry != NULL) {
if (!DNS_ADBENTRY_VALID(entry))
fprintf(f, "\tMAGIC %08x\n", entry->magic);
if (entry->lock_bucket != i)
fprintf(f, "\tWRONG BUCKET! lock_bucket %d\n",
entry->lock_bucket);
sa = &entry->sockaddr;
switch (sa->type.sa.sa_family) {
case AF_INET:
tmpp = inet_ntop(AF_INET,
&sa->type.sin.sin_addr,
tmp, sizeof tmp);
break;
case AF_INET6:
tmpp = inet_ntop(AF_INET6,
&sa->type.sin6.sin6_addr,
tmp, sizeof tmp);
break;
default:
tmpp = "UnkFamily";
}
if (tmpp == NULL)
tmpp = "CANNOT TRANSLATE ADDRESS!";
fprintf(f, "\t%p: refcnt %u flags %08x goodness %d"
" srtt %u addr %s\n",
entry, entry->refcnt, entry->flags,
entry->goodness, entry->srtt, tmpp);
entry = ISC_LIST_NEXT(entry, plink);
}
}
/*
* Unlock everything
*/
for (i = 0 ; i < DNS_ADBENTRYLIST_LENGTH ; i++)
UNLOCK(&adb->entrylocks[i]);
for (i = 0 ; i < DNS_ADBNAMELIST_LENGTH ; i++)
UNLOCK(&adb->namelocks[i]);
}
void
dns_adb_dumphandle(dns_adbhandle_t *handle, FILE *f)
{
char tmp[512];
const char *tmpp;
dns_adbaddrinfo_t *ai;
isc_sockaddr_t *sa;
/*
* Not used currently, in the API Just In Case we
* want to dump out the name and/or entries too.
*/
LOCK(&handle->lock);
fprintf(f, "Handle %p\n", handle);
fprintf(f, "\tqpending %08x partial %08x options %08x\n",
handle->query_pending, handle->partial_result,
handle->options);
fprintf(f, "\tname_bucket %d, name %p, event sender %p\n",
handle->name_bucket, handle->adbname, handle->event.sender);
ai = ISC_LIST_HEAD(handle->list);
if (ai != NULL)
fprintf(f, "\tAddresses:\n");
while (ai != NULL) {
sa = ai->sockaddr;
switch (sa->type.sa.sa_family) {
case AF_INET:
tmpp = inet_ntop(AF_INET, &sa->type.sin.sin_addr,
tmp, sizeof tmp);
break;
case AF_INET6:
tmpp = inet_ntop(AF_INET6, &sa->type.sin6.sin6_addr,
tmp, sizeof tmp);
break;
default:
tmpp = "UnkFamily";
}
if (tmpp == NULL)
tmpp = "CANNOT TRANSLATE ADDRESS!";
fprintf(f, "\t\tentry %p, flags %08x goodness %d"
" srtt %u addr %s\n",
ai->entry, ai->flags, ai->goodness, ai->srtt, tmpp);
ai = ISC_LIST_NEXT(ai, publink);
}
UNLOCK(&handle->lock);
}
static void
print_dns_name(FILE *f, dns_name_t *name)
{
char buf[257];
isc_buffer_t b;
INSIST(f != NULL);
memset(buf, 0, sizeof (buf));
isc_buffer_init(&b, buf, sizeof (buf) - 1, ISC_BUFFERTYPE_TEXT);
dns_name_totext(name, ISC_FALSE, &b);
fprintf(f, buf); /* safe, since names < 256 chars, and we memset */
}
static void
print_namehook_list(FILE *f, dns_adbname_t *n)
{
dns_adbnamehook_t *nh;
nh = ISC_LIST_HEAD(n->v4);
while (nh != NULL) {
fprintf(f, "\t\tHook %p -> entry %p\n", nh, nh->entry);
nh = ISC_LIST_NEXT(nh, plink);
}
}
static void
print_fetch_list(FILE *f, dns_adbname_t *n)
{
dns_adbfetch_t *fetch;
fetch = ISC_LIST_HEAD(n->fetches);
while (fetch != NULL) {
fprintf(f, "\t\tFetch %p\n", fetch);
fetch = ISC_LIST_NEXT(fetch, plink);
}
}
static void
print_handle_list(FILE *f, dns_adbname_t *name)
{
dns_adbhandle_t *handle;
handle = ISC_LIST_HEAD(name->handles);
while (handle != NULL) {
fprintf(f, "\t\tHandle %p\n", handle);
handle = ISC_LIST_NEXT(handle, plink);
}
}
/*
* On entry, "bucket" refers to a locked name bucket, "handle" is not NULL,
* and "name" is the name we are looking for. We will allocate an adbname
* and return a pointer to it in *adbnamep.
*
* If we return ISC_R_SUCCESS, the new name will have been allocated, and
* perhaps some namehooks will have been filled in with valid entries, and
* perhaps some fetches have been started.
*/
static isc_result_t
dbfind_name_v4(dns_adbhandle_t *handle, dns_name_t *zone,
dns_adbname_t *adbname, int bucket, isc_stdtime_t now)
{
isc_result_t result;
isc_boolean_t use_hints;
dns_rdataset_t rdataset;
dns_adb_t *adb;
INSIST(DNS_ADBHANDLE_VALID(handle));
INSIST(DNS_ADBNAME_VALID(adbname));
adb = adbname->adb;
INSIST(DNS_ADB_VALID(adb));
INSIST(bucket != DNS_ADB_INVALIDBUCKET);
if (adb->view == NULL)
return (ISC_R_NOTIMPLEMENTED);
result = ISC_R_UNEXPECTED;
use_hints = dns_name_equal(zone, dns_rootname);
dns_rdataset_init(&rdataset);
adbname->partial_result = 0;
result = dns_view_find(adb->view, &adbname->name, dns_rdatatype_a,
now, DNS_DBFIND_GLUEOK, use_hints,
&rdataset, NULL);
switch (result) {
case DNS_R_GLUE:
case DNS_R_HINT:
case DNS_R_SUCCESS:
result = import_rdatasetv4(adbname, &rdataset, now);
break;
}
if (dns_rdataset_isassociated(&rdataset))
dns_rdataset_disassociate(&rdataset);
return (result);
}
static void
fetch_callback_v4(isc_task_t *task, isc_event_t *ev)
{
dns_fetchevent_t *dev;
dns_adbname_t *name;
dns_adb_t *adb;
dns_adbfetch_t *fetch;
int bucket;
isc_eventtype_t ev_status;
isc_stdtime_t now;
isc_result_t result;
(void)task;
INSIST(ev->type == DNS_EVENT_FETCHDONE);
dev = (dns_fetchevent_t *)ev;
name = ev->arg;
INSIST(DNS_ADBNAME_VALID(name));
adb = name->adb;
INSIST(DNS_ADB_VALID(adb));
DP(("Fetch %p\n", dev->fetch));
bucket = name->lock_bucket;
LOCK(&adb->namelocks[bucket]);
/*
* Find the fetch.
*/
fetch = ISC_LIST_HEAD(name->fetches);
while (fetch != NULL && fetch->fetch != dev->fetch)
fetch = ISC_LIST_NEXT(fetch, plink);
INSIST(fetch != NULL);
ISC_LIST_UNLINK(name->fetches, fetch, plink);
dns_resolver_destroyfetch(adb->view->resolver, &fetch->fetch);
dev->fetch = NULL;
/*
* Cleanup things we don't care about.
*/
if (dev->node != NULL)
dns_db_detachnode(dev->db, &dev->node);
if (dev->db != NULL)
dns_db_detach(&dev->db);
/*
* If this name is marked as dead, clean up, throwing away
* potentially good data.
*/
if (name->dead) {
isc_boolean_t decr_adbrefcnt;
free_adbfetch(adb, &fetch);
isc_event_free(&ev);
kill_name(&name, DNS_EVENT_ADBCANCELED);
decr_adbrefcnt = ISC_FALSE;
if (adb->name_sd[bucket] && (adb->name_refcnt[bucket] == 0))
decr_adbrefcnt = ISC_TRUE;
UNLOCK(&adb->namelocks[bucket]);
if (decr_adbrefcnt)
dec_adb_irefcnt(adb, ISC_TRUE);
return;
}
/*
* Did we get back junk? If so, and there are no more fetches
* sitting out there, tell all the handles about it.
*/
if (dev->result != ISC_R_SUCCESS) {
ev_status = DNS_EVENT_ADBNOMOREADDRESSES;
goto out;
}
/*
* We got something potentially useful.
*/
result = isc_stdtime_get(&now);
if (result == ISC_R_SUCCESS)
result = import_rdatasetv4(name, &fetch->rdataset, now);
if (result == ISC_R_SUCCESS)
ev_status = DNS_EVENT_ADBMOREADDRESSES;
else
ev_status = DNS_EVENT_ADBNOMOREADDRESSES;
out:
free_adbfetch(adb, &fetch);
isc_event_free(&ev);
if (EMPTY(name->fetches)) {
clean_handles_at_name(name, ev_status);
name->query_pending &= ~DNS_ADBFIND_INET;
}
UNLOCK(&adb->namelocks[bucket]);
return;
}
static isc_result_t
fetch_name_v4(dns_adbname_t *adbname, isc_stdtime_t now)
{
isc_result_t result;
dns_adbfetch_t *fetch;
dns_rdataset_t nameservers;
dns_name_t fname;
isc_buffer_t buffer;
unsigned char ndata[256];
dns_adb_t *adb;
INSIST(DNS_ADBNAME_VALID(adbname));
adb = adbname->adb;
INSIST(DNS_ADB_VALID(adb));
isc_buffer_init(&buffer, ndata, sizeof(ndata), ISC_BUFFERTYPE_BINARY);
fetch = NULL;
dns_name_init(&fname, NULL);
dns_name_setbuffer(&fname, &buffer);
dns_rdataset_init(&nameservers);
result = dns_view_findzonecut(adb->view, &adbname->name, &fname, now,
0, ISC_TRUE, &nameservers, NULL);
if (result != ISC_R_SUCCESS)
goto cleanup;
fetch = new_adbfetch(adb);
if (fetch == NULL) {
result = ISC_R_NOMEMORY;
goto cleanup;
}
result = dns_resolver_createfetch(adb->view->resolver, &adbname->name,
dns_rdatatype_a, dns_rootname,
&nameservers, NULL, 0,
adb->task, fetch_callback_v4,
adbname, &fetch->rdataset, NULL,
&fetch->fetch);
if (result != ISC_R_SUCCESS)
goto cleanup;
ISC_LIST_APPEND(adbname->fetches, fetch, plink);
fetch = NULL; /* keep us from cleaning this up below */
cleanup:
if (fetch != NULL)
free_adbfetch(adb, &fetch);
if (dns_rdataset_isassociated(&nameservers))
dns_rdataset_disassociate(&nameservers);
return (result);
}
isc_result_t
dns_adb_marklame(dns_adb_t *adb, dns_adbaddrinfo_t *addr, dns_name_t *zone,
isc_stdtime_t expire_time)
{
dns_adbzoneinfo_t *zi;
int bucket;
REQUIRE(DNS_ADB_VALID(adb));
REQUIRE(DNS_ADBADDRINFO_VALID(addr));
REQUIRE(zone != NULL);
zi = new_adbzoneinfo(adb, zone);
if (zi == NULL)
return (ISC_R_NOMEMORY);
zi->lame_timer = expire_time;
bucket = addr->entry->lock_bucket;
LOCK(&adb->entrylocks[bucket]);
ISC_LIST_PREPEND(addr->entry->zoneinfo, zi, plink);
UNLOCK(&adb->entrylocks[bucket]);
return (ISC_R_SUCCESS);
}
void
dns_adb_adjustgoodness(dns_adb_t *adb, dns_adbaddrinfo_t *addr,
int goodness_adjustment)
{
int bucket;
int old_goodness, new_goodness;
REQUIRE(DNS_ADB_VALID(adb));
REQUIRE(DNS_ADBADDRINFO_VALID(addr));
if (goodness_adjustment == 0)
return;
bucket = addr->entry->lock_bucket;
LOCK(&adb->entrylocks[bucket]);
old_goodness = addr->entry->goodness;
if (goodness_adjustment > 0) {
if (old_goodness > INT_MAX - goodness_adjustment)
new_goodness = INT_MAX;
else
new_goodness = old_goodness + goodness_adjustment;
} else {
if (old_goodness < INT_MIN - goodness_adjustment)
new_goodness = INT_MAX;
else
new_goodness = old_goodness + goodness_adjustment;
}
addr->entry->goodness = new_goodness;
addr->goodness = new_goodness;
UNLOCK(&adb->entrylocks[bucket]);
}
void
dns_adb_adjustsrtt(dns_adb_t *adb, dns_adbaddrinfo_t *addr,
unsigned int rtt, unsigned int factor)
{
int bucket;
unsigned int new_srtt;
REQUIRE(DNS_ADB_VALID(adb));
REQUIRE(DNS_ADBADDRINFO_VALID(addr));
if (factor == 0)
factor = 4;
bucket = addr->entry->lock_bucket;
LOCK(&adb->entrylocks[bucket]);
new_srtt = (addr->entry->srtt * (factor - 1) + rtt) / factor;
addr->entry->srtt = new_srtt;
addr->srtt = new_srtt;
UNLOCK(&adb->entrylocks[bucket]);
}