diff options
Diffstat (limited to 'lib/dns/adb.c')
| -rw-r--r-- | lib/dns/adb.c | 3944 |
1 files changed, 3944 insertions, 0 deletions
diff --git a/lib/dns/adb.c b/lib/dns/adb.c new file mode 100644 index 00000000..5bcf62db --- /dev/null +++ b/lib/dns/adb.c @@ -0,0 +1,3944 @@ +/* + * Copyright (C) 1999, 2000 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 finds, 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 neither are NULL, no event was posted. + * + */ + +/* + * After we have cleaned all buckets, dump the database contents. + */ +#define DUMP_ADB_AFTER_CLEANING + +#include <config.h> + +#include <limits.h> +#include <stdio.h> +#include <string.h> + +#include <isc/assertions.h> +#include <isc/condition.h> +#include <isc/event.h> +#include <isc/log.h> +#include <isc/magic.h> +#include <isc/mutex.h> +#include <isc/mutexblock.h> +#include <isc/random.h> +#include <isc/timer.h> +#include <isc/util.h> + +#include <dns/a6.h> +#include <dns/adb.h> +#include <dns/db.h> +#include <dns/events.h> +#include <dns/fixedname.h> +#include <dns/log.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> + +#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) +#define DNS_ADBFETCH6_MAGIC 0x61644636 /* adF6. */ +#define DNS_ADBFETCH6_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBFETCH6_MAGIC) + +/* + * The number of buckets needs to be a prime (for good hashing). + * + * XXXRTH How many buckets do we need? + * + * This value must be coordinated with CLEAN_SECONDS (below). + */ +#define NBUCKETS 1009 /* how many buckets for names/addrs */ + +/* + * For type 3 negative cache entries, we will remember that the address is + * broken for this long. XXXMLG This is also used for actual addresses, too. + * The intent is to keep us from constantly asking about A/A6/AAAA records + * if the zone has extremely low TTLs. + */ +#define ADB_CACHE_MINIMUM 10 /* seconds */ + +/* + * Clean one bucket every CLEAN_SECONDS. + */ +#define CLEAN_SECONDS (300 / NBUCKETS) +#if CLEAN_SECONDS < 1 +#undef CLEAN_SECONDS +#define CLEAN_SECONDS 1 +#endif + +#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; +typedef struct dns_adbfetch6 dns_adbfetch6_t; + +struct dns_adb { + unsigned int magic; + + isc_mutex_t lock; + isc_mutex_t ilock; + 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; + int next_cleanbucket; + + 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_adbfind_t */ + isc_mempool_t *aimp; /* dns_adbaddrinfo_t */ + isc_mempool_t *afmp; /* dns_adbfetch_t */ + isc_mempool_t *af6mp; /* dns_adbfetch6_t */ + + isc_random_t rand; + + /* + * Bucketized locks and lists for names. + * + * XXXRTH Have a per-bucket structure that contains all of these? + */ + dns_adbnamelist_t names[NBUCKETS]; + isc_mutex_t namelocks[NBUCKETS]; + isc_boolean_t name_sd[NBUCKETS]; + unsigned int name_refcnt[NBUCKETS]; + + /* + * Bucketized locks for entries. + * + * XXXRTH Have a per-bucket structure that contains all of these? + */ + dns_adbentrylist_t entries[NBUCKETS]; + isc_mutex_t entrylocks[NBUCKETS]; + isc_boolean_t entry_sd[NBUCKETS]; + unsigned int entry_refcnt[NBUCKETS]; + + isc_event_t cevent; + isc_boolean_t cevent_sent; + isc_boolean_t shutting_down; + isc_eventlist_t whenshutdown; +}; + +/* + * XXXMLG Document these structures. + */ + +struct dns_adbname { + unsigned int magic; + dns_name_t name; + dns_adb_t *adb; + unsigned int partial_result; + unsigned int flags; + int lock_bucket; + dns_name_t target; + isc_stdtime_t expire_target; + isc_stdtime_t expire_v4; + isc_stdtime_t expire_v6; + unsigned int chains; + dns_adbnamehooklist_t v4; + dns_adbnamehooklist_t v6; + dns_adbfetch_t *fetch_a; + dns_adbfetch_t *fetch_aaaa; + ISC_LIST(dns_adbfetch6_t) fetches_a6; + dns_adbfindlist_t finds; + 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; +}; + +struct dns_adbfetch6 { + unsigned int magic; + unsigned int flags; + dns_adbnamehook_t *namehook; + dns_adbentry_t *entry; + dns_fetch_t *fetch; + dns_rdataset_t rdataset; + dns_a6context_t a6ctx; + ISC_LINK(dns_adbfetch6_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_stdtime_t expires; + + 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_adbfind_t *new_adbfind(dns_adb_t *); +static inline void free_adbfind(dns_adb_t *, dns_adbfind_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_adbfetch6_t *new_adbfetch6(dns_adb_t *, dns_adbname_t *, + dns_a6context_t *); +static inline void free_adbfetch6(dns_adb_t *, dns_adbfetch6_t **); +static inline dns_adbname_t *find_name_and_lock(dns_adb_t *, dns_name_t *, + unsigned int, 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_find_list(FILE *, dns_adbname_t *); +static void print_fetch_list(FILE *, dns_adbname_t *); +static inline void dec_adb_irefcnt(dns_adb_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_target(dns_adb_t *, dns_name_t *); +static void clean_finds_at_name(dns_adbname_t *, isc_eventtype_t, + unsigned int); +static void check_expire_namehooks(dns_adbname_t *, isc_stdtime_t); +static void cancel_fetches_at_name(dns_adbname_t *); +static isc_result_t dbfind_name(dns_adbname_t *, isc_stdtime_t, + dns_rdatatype_t); +static isc_result_t fetch_name_v4(dns_adbname_t *, isc_boolean_t); +static isc_result_t fetch_name_aaaa(dns_adbname_t *); +static isc_result_t fetch_name_a6(dns_adbname_t *, isc_boolean_t); +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 void shutdown_entries(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 inline void link_entry(dns_adb_t *, int, dns_adbentry_t *); +static inline void unlink_entry(dns_adb_t *, dns_adbentry_t *); +static void kill_name(dns_adbname_t **, isc_eventtype_t); +static void fetch_callback_a6(isc_task_t *, isc_event_t *); +static isc_result_t dbfind_a6(dns_adbname_t *, isc_stdtime_t); + +/* + * MUST NOT overlap DNS_ADBFIND_* flags! + */ +#define FIND_EVENT_SENT 0x40000000 +#define FIND_EVENT_FREED 0x80000000 +#define FIND_EVENTSENT(h) (((h)->flags & FIND_EVENT_SENT) != 0) +#define FIND_EVENTFREED(h) (((h)->flags & FIND_EVENT_FREED) != 0) + +#define NAME_NEEDS_POKE 0x80000000 +#define NAME_IS_DEAD 0x40000000 +#define NAME_HINT_OK DNS_ADBFIND_HINTOK +#define NAME_GLUE_OK DNS_ADBFIND_GLUEOK +#define NAME_DEAD(n) (((n)->flags & NAME_IS_DEAD) != 0) +#define NAME_NEEDSPOKE(n) (((n)->flags & NAME_NEEDS_POKE) != 0) +#define NAME_HINTOK(n) (((n)->flags & NAME_HINT_OK) != 0) +#define NAME_GLUEOK(n) (((n)->flags & NAME_GLUE_OK) != 0) + +/* + * To the name, address classes are all that really exist. If it has a + * V6 address it doesn't care if it came from an A6 chain or an AAAA query. + */ +#define NAME_HAS_V4(n) (!ISC_LIST_EMPTY((n)->v4)) +#define NAME_HAS_V6(n) (!ISC_LIST_EMPTY((n)->v6)) +#define NAME_HAS_ADDRS(n) (NAME_HAS_V4(n) || NAME_HAS_V6(n)) + +/* + * Fetches are broken out into A, AAAA, and A6 types. In some cases, + * however, it makes more sense to test for a particular class of fetches, + * like V4 or V6 above. + */ +#define NAME_FETCH_A(n) ((n)->fetch_a != NULL) +#define NAME_FETCH_AAAA(n) ((n)->fetch_aaaa != NULL) +#define NAME_FETCH_A6(n) (!ISC_LIST_EMPTY((n)->fetches_a6)) +#define NAME_FETCH_V4(n) (NAME_FETCH_A(n)) +#define NAME_FETCH_V6(n) (NAME_FETCH_AAAA(n) || NAME_FETCH_A6(n)) +#define NAME_FETCH(n) (NAME_FETCH_V4(n) || NAME_FETCH_V6(n)) + +/* + * Was this fetch started using the hints database? + * Was this the initial fetch for the A6 record? If so, we might want to + * start AAAA queries if it fails. + */ +#define FETCH_FIRST_A6 0x80000000 +#define FETCH_FIRSTA6(f) (((f)->flags & FETCH_FIRST_A6) != 0) + +/* + * Find options and tests to see if there are addresses on the list. + */ +#define FIND_WANTEVENT(fn) (((fn)->options & DNS_ADBFIND_WANTEVENT) != 0) +#define FIND_WANTEMPTYEVENT(fn) (((fn)->options & DNS_ADBFIND_EMPTYEVENT) != 0) +#define FIND_AVOIDFETCHES(fn) (((fn)->options & DNS_ADBFIND_AVOIDFETCHES) \ + != 0) +#define FIND_STARTATROOT(fn) (((fn)->options & DNS_ADBFIND_STARTATROOT) \ + != 0) +#define FIND_HINTOK(fn) (((fn)->options & DNS_ADBFIND_HINTOK) != 0) +#define FIND_GLUEOK(fn) (((fn)->options & DNS_ADBFIND_GLUEOK) != 0) +#define FIND_HAS_ADDRS(fn) (!ISC_LIST_EMPTY((fn)->list)) +#define FIND_RETURNLAME(fn) (((fn)->options & DNS_ADBFIND_RETURNLAME) != 0) + +/* + * These are currently used on simple unsigned ints, so they are + * not really associated with any particular type. + */ +#define WANT_INET(x) (((x) & DNS_ADBFIND_INET) != 0) +#define WANT_INET6(x) (((x) & DNS_ADBFIND_INET6) != 0) + +#define EXPIRE_OK(exp, now) ((exp == INT_MAX) || (exp < now)) + +/* + * Find out if the flags on a name (nf) indicate if it is a hint or + * glue, and compare this to the appropriate bits set in o, to see if + * this is ok. + */ +#define GLUE_OK(nf, o) (!NAME_GLUEOK(nf) || (((o) & DNS_ADBFIND_GLUEOK) != 0)) +#define HINT_OK(nf, o) (!NAME_HINTOK(nf) || (((o) & DNS_ADBFIND_HINTOK) != 0)) +#define GLUEHINT_OK(nf, o) (GLUE_OK(nf, o) || HINT_OK(nf, o)) + +#define ENTER_LEVEL 50 +#define EXIT_LEVEL ENTER_LEVEL +#define CLEAN_LEVEL 100 +#define DEF_LEVEL 5 +#define NCACHE_LEVEL 20 + +#define NCACHE_RESULT(r) ((r) == DNS_R_NCACHENXDOMAIN || \ + (r) == DNS_R_NCACHENXRRSET) +#define AUTH_NX(r) ((r) == DNS_R_NXDOMAIN || \ + (r) == DNS_R_NXRRSET) + + +static void +DP(int level, char *format, ...) +{ + va_list args; + + va_start(args, format); + isc_log_vwrite(dns_lctx, + DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_ADB, + ISC_LOG_DEBUG(level), format, args); + va_end(args); +} + +/* + * Requires the adbname bucket be locked and that no entry buckets be locked. + * + * This code handles A and AAAA rdatasets only. + */ +static isc_result_t +import_rdataset(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; + struct in6_addr in6a; + isc_sockaddr_t sockaddr; + dns_adbentry_t *foundentry; /* NO CLEAN UP! */ + int addr_bucket; + isc_boolean_t new_addresses_added; + dns_rdatatype_t rdtype; + unsigned int findoptions; + + INSIST(DNS_ADBNAME_VALID(adbname)); + adb = adbname->adb; + INSIST(DNS_ADB_VALID(adb)); + + rdtype = rdataset->type; + INSIST((rdtype == dns_rdatatype_a) || (rdtype == dns_rdatatype_aaaa)); + if (rdtype == dns_rdatatype_a) + findoptions = DNS_ADBFIND_INET; + else + findoptions = DNS_ADBFIND_INET6; + + addr_bucket = DNS_ADB_INVALIDBUCKET; + new_addresses_added = ISC_FALSE; + + nh = NULL; + result = dns_rdataset_first(rdataset); + while (result == ISC_R_SUCCESS) { + dns_rdataset_current(rdataset, &rdata); + if (rdtype == dns_rdatatype_a) { + INSIST(rdata.length == 4); + memcpy(&ina.s_addr, rdata.data, 4); + isc_sockaddr_fromin(&sockaddr, &ina, 53); + } else { + INSIST(rdata.length == 16); + memcpy(in6a.s6_addr, rdata.data, 16); + isc_sockaddr_fromin6(&sockaddr, &in6a, 53); + } + + if (IN6_IS_ADDR_V4MAPPED(&sockaddr.type.sin6.sin6_addr) + || IN6_IS_ADDR_V4COMPAT(&sockaddr.type.sin6.sin6_addr)) { + DP(1, "Ignoring IPv6 mapped IPv4 address"); + goto next; + } + + INSIST(nh == NULL); + nh = new_adbnamehook(adb, NULL); + if (nh == NULL) { + adbname->partial_result |= findoptions; + result = ISC_R_NOMEMORY; + goto fail; + } + + 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 |= findoptions; + result = ISC_R_NOMEMORY; + goto fail; + } + + entry->sockaddr = sockaddr; + entry->refcnt = 1; + + nh->entry = entry; + + link_entry(adb, addr_bucket, entry); + } else { + foundentry->refcnt++; + nh->entry = foundentry; + } + + new_addresses_added = ISC_TRUE; + if (rdtype == dns_rdatatype_a) + ISC_LIST_APPEND(adbname->v4, nh, plink); + else + ISC_LIST_APPEND(adbname->v6, nh, plink); + nh = NULL; + + next: + + result = dns_rdataset_next(rdataset); + } + + fail: + if (nh != NULL) + free_adbnamehook(adb, &nh); + + if (addr_bucket != DNS_ADB_INVALIDBUCKET) + UNLOCK(&adb->entrylocks[addr_bucket]); + + rdataset->ttl = ISC_MAX(rdataset->ttl, ADB_CACHE_MINIMUM); + + if (rdtype == dns_rdatatype_a) { + DP(NCACHE_LEVEL, "expire_v4 set to MIN(%u,%u) import_rdataset", + adbname->expire_v4, now + rdataset->ttl); + adbname->expire_v4 = ISC_MIN(adbname->expire_v4, + now + rdataset->ttl); + } else { + DP(NCACHE_LEVEL, "expire_v6 set to MIN(%u,%u) import_rdataset", + adbname->expire_v6, now + rdataset->ttl); + adbname->expire_v6 = ISC_MIN(adbname->expire_v6, + now + rdataset->ttl); + } + + if (new_addresses_added) { + /* + * Lie a little here. This is more or less so code that cares + * can find out if any new information was added or not. + */ + return (ISC_R_SUCCESS); + } + + return (result); +} + +static void +import_a6(dns_a6context_t *a6ctx) +{ + dns_adbname_t *name; + dns_adb_t *adb; + dns_adbnamehook_t *nh; + dns_adbentry_t *foundentry; /* NO CLEAN UP! */ + int addr_bucket; + isc_sockaddr_t sockaddr; + + name = a6ctx->arg; + INSIST(DNS_ADBNAME_VALID(name)); + adb = name->adb; + INSIST(DNS_ADB_VALID(adb)); + + addr_bucket = DNS_ADB_INVALIDBUCKET; + + DP(ENTER_LEVEL, "ENTER: import_a6() name %p", name); + + nh = new_adbnamehook(adb, NULL); + if (nh == NULL) { + name->partial_result |= DNS_ADBFIND_INET6; /* clear for AAAA */ + goto fail; + } + + isc_sockaddr_fromin6(&sockaddr, &a6ctx->in6addr, 53); + + if (IN6_IS_ADDR_V4MAPPED(&sockaddr.type.sin6.sin6_addr) + || IN6_IS_ADDR_V4COMPAT(&sockaddr.type.sin6.sin6_addr)) { + DP(1, "Ignoring IPv6 mapped IPv4 address"); + goto fail; + } + + foundentry = find_entry_and_lock(adb, &sockaddr, &addr_bucket); + if (foundentry == NULL) { + dns_adbentry_t *entry; + entry = new_adbentry(adb); + if (entry == NULL) { + name->partial_result |= DNS_ADBFIND_INET6; + goto fail; + } + + entry->sockaddr = sockaddr; + entry->refcnt = 1; + nh->entry = entry; + link_entry(adb, addr_bucket, entry); + } else { + foundentry->refcnt++; + nh->entry = foundentry; + } + + ISC_LIST_APPEND(name->v6, nh, plink); + nh = NULL; + + fail: + DP(NCACHE_LEVEL, "expire_v6 set to MIN(%u,%u) in import_v6", + name->expire_v6, a6ctx->expiration); + name->expire_v6 = ISC_MIN(name->expire_v6, a6ctx->expiration); + + name->flags |= NAME_NEEDS_POKE; + + if (nh != NULL) + free_adbnamehook(adb, &nh); + + if (addr_bucket != DNS_ADB_INVALIDBUCKET) + UNLOCK(&adb->entrylocks[addr_bucket]); +} + +/* + * 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(DEF_LEVEL, "killing name %p", name); + + /* + * If we're dead already, just check to see if we should go + * away now or not. + */ + if (NAME_DEAD(name) && !NAME_FETCH(name)) { + 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_finds_at_name(name, ev, DNS_ADBFIND_ADDRESSMASK); + clean_namehooks(adb, &name->v4); + clean_namehooks(adb, &name->v6); + clean_target(adb, &name->target); + + /* + * If fetches are running, cancel them. If none are running, we can + * just kill the name here. + */ + if (!NAME_FETCH(name)) { + unlink_name(adb, name); + free_adbname(adb, &name); + } else { + name->flags |= NAME_IS_DEAD; + cancel_fetches_at_name(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_FETCH_V4(name) && EXPIRE_OK(name->expire_v4, now)) { + if (NAME_HAS_V4(name)) { + DP(DEF_LEVEL, "expiring v4 for name %p", name); + clean_namehooks(adb, &name->v4); + name->partial_result &= ~DNS_ADBFIND_INET; + } + name->expire_v4 = INT_MAX; + } + + /* + * Check to see if we need to remove the v6 addresses + */ + if (!NAME_FETCH_V6(name) && EXPIRE_OK(name->expire_v6, now)) { + if (NAME_HAS_V6(name)) { + DP(DEF_LEVEL, "expiring v6 for name %p", name); + clean_namehooks(adb, &name->v6); + name->partial_result &= ~DNS_ADBFIND_INET6; + } + name->expire_v6 = INT_MAX; + } + + /* + * Check to see if we need to remove the alias target. + */ + if (EXPIRE_OK(name->expire_target, now)) { + clean_target(adb, &name->target); + name->expire_target = INT_MAX; + } +} + +/* + * 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]--; + if (adb->name_sd[bucket] && adb->name_refcnt[bucket] == 0) + dec_adb_irefcnt(adb); +} + +/* + * Requires the entry's bucket be locked. + */ +static inline void +link_entry(dns_adb_t *adb, int bucket, dns_adbentry_t *entry) +{ + ISC_LIST_PREPEND(adb->entries[bucket], entry, plink); + entry->lock_bucket = bucket; + adb->entry_refcnt[bucket]++; +} + +/* + * Requires the entry's bucket be locked. + */ +static inline void +unlink_entry(dns_adb_t *adb, dns_adbentry_t *entry) +{ + int bucket; + + bucket = entry->lock_bucket; + INSIST(bucket != DNS_ADB_INVALIDBUCKET); + + ISC_LIST_UNLINK(adb->entries[bucket], entry, plink); + entry->lock_bucket = DNS_ADB_INVALIDBUCKET; + INSIST(adb->entry_refcnt[bucket] > 0); + adb->entry_refcnt[bucket]--; + if (adb->entry_sd[bucket] && adb->entry_refcnt[bucket] == 0) + dec_adb_irefcnt(adb); +} + +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 < NBUCKETS ; bucket++) { + LOCK(&adb->namelocks[bucket]); + adb->name_sd[bucket] = ISC_TRUE; + + name = ISC_LIST_HEAD(adb->names[bucket]); + if (name == NULL) { + /* + * This bucket has no names. We must decrement the + * irefcnt ourselves, since it will not be + * automatically triggered by a name being unlinked. + */ + dec_adb_irefcnt(adb); + } else { + /* + * Run through the list. For each name, clean up finds + * found there, and cancel any fetches running. When + * all the fetches are canceled, the name will destroy + * itself. + */ + while (name != NULL) { + next_name = ISC_LIST_NEXT(name, plink); + kill_name(&name, DNS_EVENT_ADBSHUTDOWN); + name = next_name; + } + } + + UNLOCK(&adb->namelocks[bucket]); + } +} + +/* + * The ADB _MUST_ be locked before calling. Also, exit conditions must be + * checked after calling this function. + */ +static void +shutdown_entries(dns_adb_t *adb) +{ + int bucket; + dns_adbentry_t *entry; + dns_adbentry_t *next_entry; + + for (bucket = 0 ; bucket < NBUCKETS ; bucket++) { + LOCK(&adb->entrylocks[bucket]); + adb->entry_sd[bucket] = ISC_TRUE; + + entry = ISC_LIST_HEAD(adb->entries[bucket]); + if (entry == NULL) { + /* + * This bucket has no entries. We must decrement the + * irefcnt ourselves, since it will not be + * automatically triggered by an entry being unlinked. + */ + dec_adb_irefcnt(adb); + } else { + /* + * Run through the list. Cleanup any entries not + * associated with names, and which are not in use. + */ + while (entry != NULL) { + next_entry = ISC_LIST_NEXT(entry, plink); + if (entry->refcnt == 0 && + entry->expires != 0) { + unlink_entry(adb, entry); + free_adbentry(adb, &entry); + } + entry = next_entry; + } + } + + UNLOCK(&adb->entrylocks[bucket]); + } +} + +/* + * Name bucket must be locked + */ +static void +cancel_fetches_at_name(dns_adbname_t *name) +{ + dns_adbfetch6_t *fetch6; + + if (NAME_FETCH_A(name)) + dns_resolver_cancelfetch(name->fetch_a->fetch); + + + if (NAME_FETCH_AAAA(name)) + dns_resolver_cancelfetch(name->fetch_aaaa->fetch); + + + fetch6 = ISC_LIST_HEAD(name->fetches_a6); + while (fetch6 != NULL) { + dns_resolver_cancelfetch(fetch6->fetch); + fetch6 = ISC_LIST_NEXT(fetch6, 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]); +} + +static void +clean_target(dns_adb_t *adb, dns_name_t *target) { + if (dns_name_countlabels(target) > 0) { + dns_name_free(target, adb->mctx); + dns_name_init(target, NULL); + } +} + +static isc_result_t +set_target(dns_adb_t *adb, dns_name_t *name, dns_name_t *fname, + dns_rdataset_t *rdataset, dns_name_t *target) +{ + isc_result_t result; + dns_namereln_t namereln; + unsigned int nlabels, nbits; + int order; + dns_rdata_t rdata; + isc_region_t r; + dns_name_t tname; + dns_fixedname_t fixed1, fixed2; + dns_name_t *prefix, *new_target; + + REQUIRE(dns_name_countlabels(target) == 0); + + if (rdataset->type == dns_rdatatype_cname) { + /* + * Copy the CNAME's target into the target name. + */ + result = dns_rdataset_first(rdataset); + if (result != ISC_R_SUCCESS) + return (result); + dns_rdataset_current(rdataset, &rdata); + r.base = rdata.data; + r.length = rdata.length; + dns_name_init(&tname, NULL); + dns_name_fromregion(&tname, &r); + result = dns_name_dup(&tname, adb->mctx, target); + if (result != ISC_R_SUCCESS) + return (result); + } else { + INSIST(rdataset->type == dns_rdatatype_dname); + namereln = dns_name_fullcompare(name, fname, &order, + &nlabels, &nbits); + INSIST(namereln == dns_namereln_subdomain); + /* + * Get the target name of the DNAME. + */ + result = dns_rdataset_first(rdataset); + if (result != ISC_R_SUCCESS) + return (result); + dns_rdataset_current(rdataset, &rdata); + r.base = rdata.data; + r.length = rdata.length; + dns_name_init(&tname, NULL); + dns_name_fromregion(&tname, &r); + /* + * Construct the new target name. + */ + dns_fixedname_init(&fixed1); + prefix = dns_fixedname_name(&fixed1); + dns_fixedname_init(&fixed2); + new_target = dns_fixedname_name(&fixed2); + result = dns_name_split(name, nlabels, nbits, prefix, NULL); + if (result != ISC_R_SUCCESS) + return (result); + result = dns_name_concatenate(prefix, &tname, new_target, + NULL); + if (result != ISC_R_SUCCESS) + return (result); + result = dns_name_dup(new_target, adb->mctx, target); + if (result != ISC_R_SUCCESS) + return (result); + } + + return (ISC_R_SUCCESS); +} + +/* + * Assumes nothing is locked, since this is called by the client. + */ +static void +event_free(isc_event_t *event) +{ + dns_adbfind_t *find; + + INSIST(event != NULL); + find = event->destroy_arg; + INSIST(DNS_ADBFIND_VALID(find)); + + LOCK(&find->lock); + find->flags |= FIND_EVENT_FREED; + event->destroy_arg = NULL; + UNLOCK(&find->lock); +} + +/* + * Assumes the name bucket is locked. + */ +static void +clean_finds_at_name(dns_adbname_t *name, isc_eventtype_t evtype, + unsigned int addrs) +{ + isc_event_t *ev; + isc_task_t *task; + dns_adbfind_t *find; + dns_adbfind_t *next_find; + isc_boolean_t process; + unsigned int wanted; + + DP(ENTER_LEVEL, + "ENTER clean_finds_at_name, name %p, evtype %08x, addrs %08x", + name, evtype, addrs); + + find = ISC_LIST_HEAD(name->finds); + while (find != NULL) { + LOCK(&find->lock); + next_find = ISC_LIST_NEXT(find, plink); + + process = ISC_FALSE; + wanted = find->flags & DNS_ADBFIND_ADDRESSMASK; + + switch (evtype) { + case DNS_EVENT_ADBMOREADDRESSES: + DP(3, "DNS_EVENT_ADBMOREADDRESSES"); + if ((wanted & addrs) != 0) { + DP(3, "processing"); + find->flags &= ~addrs; + process = ISC_TRUE; + } + break; + case DNS_EVENT_ADBNOMOREADDRESSES: + DP(3, "DNS_EVENT_ADBNOMOREADDRESSES"); + find->flags &= ~addrs; + wanted = find->flags & DNS_ADBFIND_ADDRESSMASK; + if (wanted == 0) { + process = ISC_TRUE; + DP(3, "processing"); + } + break; + default: + find->flags &= ~addrs; + process = ISC_TRUE; + } + + if (process) { + DP(DEF_LEVEL, "cfan: processing find %p", find); + /* + * Unlink the find from the name, letting the caller + * call dns_adb_destroyfind() on it to clean it up + * later. + */ + ISC_LIST_UNLINK(name->finds, find, plink); + find->adbname = NULL; + find->name_bucket = DNS_ADB_INVALIDBUCKET; + + INSIST(!FIND_EVENTSENT(find)); + + ev = &find->event; + task = ev->sender; + ev->sender = find; + ev->type = evtype; + ev->destroy = event_free; + ev->destroy_arg = find; + + DP(DEF_LEVEL, + "Sending event %p to task %p for find %p", + ev, task, find); + + isc_task_sendanddetach(&task, &ev); + } else { + DP(DEF_LEVEL, "cfan: skipping find %p", find); + } + + UNLOCK(&find->lock); + find = next_find; + } + + DP(ENTER_LEVEL, "EXIT clean_finds_at_name, name %p", name); +} + +static inline void +check_exit(dns_adb_t *adb) +{ + isc_event_t *event, *next_event; + isc_task_t *etask; + isc_boolean_t zeroirefcnt; + + /* + * The caller must be holding the adb lock. + */ + + LOCK(&adb->ilock); + if (adb->irefcnt == 0) + zeroirefcnt = ISC_TRUE; + else + zeroirefcnt = ISC_FALSE; + UNLOCK(&adb->ilock); + + if (adb->shutting_down && zeroirefcnt && + isc_mempool_getallocated(adb->ahmp) == 0) { + /* + * We're now shutdown. Send any whenshutdown events. + */ + for (event = ISC_LIST_HEAD(adb->whenshutdown); + event != NULL; + event = next_event) { + next_event = ISC_LIST_NEXT(event, link); + ISC_LIST_UNLINK(adb->whenshutdown, event, link); + etask = event->sender; + event->sender = adb; + isc_task_sendanddetach(&etask, &event); + } + /* + * If there aren't any external references either, we're + * done. Send the control event to initiate shutdown. + */ + if (adb->erefcnt == 0) { + INSIST(!adb->cevent_sent); /* Sanity check. */ + event = &adb->cevent; + isc_task_send(adb->task, &event); + adb->cevent_sent = ISC_TRUE; + } + } +} + +static inline void +dec_adb_irefcnt(dns_adb_t *adb) +{ + LOCK(&adb->ilock); + + INSIST(adb->irefcnt > 0); + adb->irefcnt--; + + UNLOCK(&adb->ilock); +} + +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--; + + if (adb->erefcnt == 0) + 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 && + (adb->entry_sd[bucket] || entry->expires == 0)) { + destroy_entry = ISC_TRUE; + unlink_entry(adb, entry); + } + + 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); + } + dns_name_init(&name->target, NULL); + name->magic = DNS_ADBNAME_MAGIC; + name->adb = adb; + name->partial_result = 0; + name->flags = 0; + name->expire_v4 = INT_MAX; + name->expire_v6 = INT_MAX; + name->expire_target = INT_MAX; + name->chains = 0; + name->lock_bucket = DNS_ADB_INVALIDBUCKET; + ISC_LIST_INIT(name->v4); + ISC_LIST_INIT(name->v6); + name->fetch_a = NULL; + name->fetch_aaaa = NULL; + ISC_LIST_INIT(name->fetches_a6); + ISC_LIST_INIT(name->finds); + 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(!NAME_HAS_V4(n)); + INSIST(!NAME_HAS_V6(n)); + INSIST(!NAME_FETCH(n)); + INSIST(ISC_LIST_EMPTY(n->finds)); + 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->edns_level = -1; + e->goodness = 0; + isc_random_get(&adb->rand, &r); + e->srtt = (r & 0x1f) + 1; + e->expires = 0; + 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_adbfind_t * +new_adbfind(dns_adb_t *adb) +{ + dns_adbfind_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->partial_result = 0; + h->options = 0; + h->flags = 0; + ISC_LINK_INIT(h, publink); + ISC_LINK_INIT(h, plink); + ISC_LIST_INIT(h->list); + h->adbname = NULL; + h->name_bucket = DNS_ADB_INVALIDBUCKET; + + /* + * private members + */ + result = isc_mutex_init(&h->lock); + if (result != ISC_R_SUCCESS) { + UNEXPECTED_ERROR(__FILE__, __LINE__, + "isc_mutex_init failed in new_adbfind()"); + 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_ADBFIND_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); + + 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; + + 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); +} + +/* + * Caller must be holding the name lock. + */ +static isc_result_t +a6find(void *arg, dns_name_t *a6name, dns_rdatatype_t type, isc_stdtime_t now, + dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset) +{ + dns_adbname_t *name; + dns_adb_t *adb; + + name = arg; + INSIST(DNS_ADBNAME_VALID(name)); + adb = name->adb; + INSIST(DNS_ADB_VALID(adb)); + + return (dns_view_simplefind(adb->view, a6name, type, now, + DNS_DBFIND_GLUEOK, ISC_FALSE, + rdataset, sigrdataset)); +} + +/* + * Caller must be holding the name lock. + */ +static void +a6missing(dns_a6context_t *a6ctx, dns_name_t *a6name) { + dns_adbname_t *name; + dns_adb_t *adb; + dns_adbfetch6_t *fetch; + isc_result_t result; + + name = a6ctx->arg; + INSIST(DNS_ADBNAME_VALID(name)); + adb = name->adb; + INSIST(DNS_ADB_VALID(adb)); + + fetch = new_adbfetch6(adb, name, a6ctx); + if (fetch == NULL) { + name->partial_result |= DNS_ADBFIND_INET6; + return; + } + + result = dns_resolver_createfetch(adb->view->resolver, a6name, + dns_rdatatype_a6, + NULL, NULL, NULL, 0, + adb->task, fetch_callback_a6, + name, &fetch->rdataset, NULL, + &fetch->fetch); + if (result != ISC_R_SUCCESS) + goto cleanup; + + name->chains = a6ctx->chains; + ISC_LIST_APPEND(name->fetches_a6, fetch, plink); + + cleanup: + if (result != ISC_R_SUCCESS) { + free_adbfetch6(adb, &fetch); + name->partial_result |= DNS_ADBFIND_INET6; + } +} + +static inline dns_adbfetch6_t * +new_adbfetch6(dns_adb_t *adb, dns_adbname_t *name, dns_a6context_t *a6ctx) +{ + dns_adbfetch6_t *f; + + f = isc_mempool_get(adb->af6mp); + if (f == NULL) + return (NULL); + + f->magic = 0; + f->namehook = NULL; + f->entry = NULL; + f->fetch = NULL; + f->flags = 0; + + 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); + + dns_a6_init(&f->a6ctx, a6find, NULL, import_a6, + a6missing, name); + if (a6ctx != NULL) + dns_a6_copy(a6ctx, &f->a6ctx); + + f->magic = DNS_ADBFETCH6_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->af6mp, f); + return (NULL); +} + +static inline void +free_adbfetch6(dns_adb_t *adb, dns_adbfetch6_t **fetch) +{ + dns_adbfetch6_t *f; + + INSIST(fetch != NULL && DNS_ADBFETCH6_VALID(*fetch)); + f = *fetch; + *fetch = NULL; + + 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->af6mp, f); +} + +static inline void +free_adbfind(dns_adb_t *adb, dns_adbfind_t **findp) +{ + dns_adbfind_t *find; + + INSIST(findp != NULL && DNS_ADBFIND_VALID(*findp)); + find = *findp; + *findp = NULL; + + INSIST(!FIND_HAS_ADDRS(find)); + INSIST(!ISC_LINK_LINKED(find, publink)); + INSIST(!ISC_LINK_LINKED(find, plink)); + INSIST(find->name_bucket == DNS_ADB_INVALIDBUCKET); + INSIST(find->adbname == NULL); + + find->magic = 0; + + isc_mutex_destroy(&find->lock); + isc_mempool_put(adb->ahmp, find); +} + +/* + * 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, + unsigned int options, int *bucketp) +{ + dns_adbname_t *adbname; + int bucket; + + bucket = dns_name_hash(name, ISC_FALSE) % NBUCKETS; + + 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 (!NAME_DEAD(adbname)) { + if (dns_name_equal(name, &adbname->name) + && GLUEHINT_OK(adbname, options)) + 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) % NBUCKETS; + + 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_adbfind_t *find, dns_name_t *zone, + dns_adbname_t *name, isc_stdtime_t now) +{ + dns_adbnamehook_t *namehook; + dns_adbaddrinfo_t *addrinfo; + int bucket; + + bucket = DNS_ADB_INVALIDBUCKET; + + if (find->options & DNS_ADBFIND_INET) { + namehook = ISC_LIST_HEAD(name->v4); + while (namehook != NULL) { + bucket = namehook->entry->lock_bucket; + LOCK(&adb->entrylocks[bucket]); + if (!FIND_RETURNLAME(find) + && entry_is_bad_for_zone(adb, namehook->entry, + zone, now)) { + find->options |= DNS_ADBFIND_LAMEPRUNED; + goto nextv4; + } + addrinfo = new_adbaddrinfo(adb, namehook->entry); + if (addrinfo == NULL) { + find->partial_result |= DNS_ADBFIND_INET; + goto out; + } + /* + * Found a valid entry. Add it to the find's list. + */ + inc_entry_refcnt(adb, namehook->entry, ISC_FALSE); + ISC_LIST_APPEND(find->list, addrinfo, publink); + addrinfo = NULL; + nextv4: + UNLOCK(&adb->entrylocks[bucket]); + bucket = DNS_ADB_INVALIDBUCKET; + namehook = ISC_LIST_NEXT(namehook, plink); + } + } + + if (find->options & DNS_ADBFIND_INET6) { + 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) { + find->partial_result |= DNS_ADBFIND_INET6; + goto out; + } + /* + * Found a valid entry. Add it to the find's list. + */ + inc_entry_refcnt(adb, namehook->entry, ISC_FALSE); + ISC_LIST_APPEND(find->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) badness will occur. + */ + LOCK(&adb->lock); + isc_timer_detach(&adb->timer); + UNLOCK(&adb->lock); + isc_event_free(&ev); + destroy(adb); +} + +/* + * name bucket must be locked; adb may be locked; no other locks held. + */ +static void +check_expire_name(dns_adbname_t **namep, isc_stdtime_t now) +{ + dns_adbname_t *name; + + INSIST(namep != NULL && DNS_ADBNAME_VALID(*namep)); + name = *namep; + *namep = NULL; + + if (NAME_HAS_V4(name) || NAME_HAS_V6(name)) + return; + if (NAME_FETCH(name)) + return; + if (!EXPIRE_OK(name->expire_v4, now)) + return; + if (!EXPIRE_OK(name->expire_v6, now)) + return; + if (!EXPIRE_OK(name->expire_target, now)) + return; + + /* + * The name is empty. Delete it. + */ + kill_name(&name, DNS_EVENT_ADBEXPIRED); + + /* + * Our caller, or one of its callers, will be calling check_exit() at + * some point, so we don't need to do it here. + */ +} + +/* + * entry bucket must be locked; adb may be locked; no other locks held. + */ +static void +check_expire_entry(dns_adb_t *adb, dns_adbentry_t **entryp, isc_stdtime_t now) +{ + dns_adbentry_t *entry; + + INSIST(entryp != NULL && DNS_ADBENTRY_VALID(*entryp)); + entry = *entryp; + *entryp = NULL; + + if (entry->refcnt != 0) + return; + if (entry->expires == 0 || entry->expires > now) + return; + + /* + * The entry is not in use. Delete it. + */ + DP(DEF_LEVEL, "killing entry %p", entry); + INSIST(ISC_LINK_LINKED(entry, plink)); + unlink_entry(adb, entry); + free_adbentry(adb, &entry); +} + +/* + * ADB must be locked, and no other locks held. + */ +static void +cleanup_names(dns_adb_t *adb, int bucket, isc_stdtime_t now) +{ + dns_adbname_t *name; + dns_adbname_t *next_name; + + DP(CLEAN_LEVEL, "cleaning name bucket %d", bucket); + + LOCK(&adb->namelocks[bucket]); + if (adb->name_sd[bucket]) { + UNLOCK(&adb->namelocks[bucket]); + return; + } + + name = ISC_LIST_HEAD(adb->names[bucket]); + while (name != NULL) { + next_name = ISC_LIST_NEXT(name, plink); + check_expire_namehooks(name, now); + check_expire_name(&name, now); + name = next_name; + } + UNLOCK(&adb->namelocks[bucket]); +} + +/* + * ADB must be locked, and no other locks held. + */ +static void +cleanup_entries(dns_adb_t *adb, int bucket, isc_stdtime_t now) +{ + dns_adbentry_t *entry, *next_entry; + + DP(CLEAN_LEVEL, "cleaning entry bucket %d", bucket); + + LOCK(&adb->entrylocks[bucket]); + entry = ISC_LIST_HEAD(adb->entries[bucket]); + while (entry != NULL) { + next_entry = ISC_LIST_NEXT(entry, plink); + check_expire_entry(adb, &entry, now); + entry = next_entry; + } + UNLOCK(&adb->entrylocks[bucket]); +} + +static void +timer_cleanup(isc_task_t *task, isc_event_t *ev) +{ + dns_adb_t *adb; + isc_result_t result; + isc_stdtime_t now; + + (void)task; /* not used */ + + adb = ev->arg; + INSIST(DNS_ADB_VALID(adb)); + + LOCK(&adb->lock); + + isc_stdtime_get(&now); + + /* + * Call our cleanup routines. + */ + cleanup_names(adb, adb->next_cleanbucket, now); + cleanup_entries(adb, adb->next_cleanbucket, now); + + /* + * Set the next bucket to be cleaned. + */ + adb->next_cleanbucket++; + if (adb->next_cleanbucket >= NBUCKETS) { + adb->next_cleanbucket = 0; +#ifdef DUMP_ADB_AFTER_CLEANING + dump_adb(adb, stdout); +#endif + } + + /* + * 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_mempool_destroy(&adb->af6mp); + + isc_mutexblock_destroy(adb->entrylocks, NBUCKETS); + isc_mutexblock_destroy(adb->namelocks, NBUCKETS); + + isc_mutex_destroy(&adb->ilock); + 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->af6mp = NULL; + adb->task = NULL; + adb->timer = NULL; + adb->mctx = mem; + adb->view = view; + adb->timermgr = timermgr; + adb->taskmgr = taskmgr; + adb->next_cleanbucket = 0; + ISC_EVENT_INIT(&adb->cevent, sizeof adb->cevent, 0, NULL, + DNS_EVENT_ADBCONTROL, shutdown_task, adb, + adb, NULL, NULL); + adb->cevent_sent = ISC_FALSE; + adb->shutting_down = ISC_FALSE; + ISC_LIST_INIT(adb->whenshutdown); + + 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; + + result = isc_mutex_init(&adb->ilock); + if (result != ISC_R_SUCCESS) + goto fail0d; + + /* + * Initialize the bucket locks for names and elements. + * May as well initialize the list heads, too. + */ + result = isc_mutexblock_init(adb->namelocks, NBUCKETS); + if (result != ISC_R_SUCCESS) + goto fail1; + for (i = 0 ; i < NBUCKETS ; i++) { + ISC_LIST_INIT(adb->names[i]); + adb->name_sd[i] = ISC_FALSE; + adb->name_refcnt[i] = 0; + adb->irefcnt++; + } + for (i = 0 ; i < NBUCKETS ; i++) { + ISC_LIST_INIT(adb->entries[i]); + adb->entry_sd[i] = ISC_FALSE; + adb->entry_refcnt[i] = 0; + adb->irefcnt++; + } + result = isc_mutexblock_init(adb->entrylocks, NBUCKETS); + 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_adbfind_t, adb->ahmp, ISC_TRUE, "adbfind"); + MPINIT(dns_adbaddrinfo_t, adb->aimp, ISC_TRUE, "adbaddrinfo"); + MPINIT(dns_adbfetch_t, adb->afmp, ISC_TRUE, "adbfetch"); + MPINIT(dns_adbfetch6_t, adb->af6mp, ISC_TRUE, "adbfetch6"); + +#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; + isc_task_setname(adb->task, "ADB", adb); + /* + * XXXMLG When this is changed to be a config file option, + */ + 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, NBUCKETS); + + fail2: /* clean up namelocks */ + isc_mutexblock_destroy(adb->namelocks, NBUCKETS); + + 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->afmp != NULL) + isc_mempool_destroy(&adb->afmp); + if (adb->af6mp != NULL) + isc_mempool_destroy(&adb->af6mp); + + isc_mutex_destroy(&adb->ilock); + fail0d: + 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) + INSIST(adb->shutting_down); + UNLOCK(&adb->lock); +} + +void +dns_adb_whenshutdown(dns_adb_t *adb, isc_task_t *task, isc_event_t **eventp) +{ + isc_task_t *clone; + isc_event_t *event; + isc_boolean_t zeroirefcnt = ISC_FALSE; + + /* + * Send '*eventp' to 'task' when 'adb' has shutdown. + */ + + REQUIRE(DNS_ADB_VALID(adb)); + REQUIRE(eventp != NULL); + + event = *eventp; + *eventp = NULL; + + LOCK(&adb->lock); + + LOCK(&adb->ilock); + if (adb->irefcnt == 0) + zeroirefcnt = ISC_TRUE; + else + zeroirefcnt = ISC_FALSE; + UNLOCK(&adb->ilock); + + if (adb->shutting_down && zeroirefcnt && + isc_mempool_getallocated(adb->ahmp) == 0) { + /* + * We're already shutdown. Send the event. + */ + event->sender = adb; + isc_task_send(task, &event); + } else { + clone = NULL; + isc_task_attach(task, &clone); + event->sender = clone; + ISC_LIST_APPEND(adb->whenshutdown, event, link); + } + + UNLOCK(&adb->lock); +} + +void +dns_adb_shutdown(dns_adb_t *adb) { + + /* + * Shutdown 'adb'. + */ + + LOCK(&adb->lock); + + if (!adb->shutting_down) { + adb->shutting_down = ISC_TRUE; + shutdown_names(adb); + shutdown_entries(adb); + check_exit(adb); + } + + UNLOCK(&adb->lock); +} + +isc_result_t +dns_adb_createfind(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_name_t *target, + dns_adbfind_t **findp) +{ + dns_adbfind_t *find; + dns_adbname_t *adbname; + int bucket; + isc_boolean_t want_event, start_at_root, alias; + isc_result_t result; + unsigned int wanted_addresses; + unsigned int wanted_fetches; + unsigned int query_pending; + + REQUIRE(DNS_ADB_VALID(adb)); + if (task != NULL) { + REQUIRE(action != NULL); + } + REQUIRE(name != NULL); + REQUIRE(zone != NULL); + REQUIRE(findp != NULL && *findp == NULL); + REQUIRE(target == NULL || dns_name_hasbuffer(target)); + + REQUIRE((options & DNS_ADBFIND_ADDRESSMASK) != 0); + + result = ISC_R_UNEXPECTED; + wanted_addresses = (options & DNS_ADBFIND_ADDRESSMASK); + wanted_fetches = 0; + query_pending = 0; + want_event = ISC_FALSE; + start_at_root = ISC_FALSE; + alias = ISC_FALSE; + + if (now == 0) + isc_stdtime_get(&now); + + /* + * XXXMLG Move this comment somewhere else! + * + * 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. + */ + + find = new_adbfind(adb); + if (find == NULL) + return (ISC_R_NOMEMORY); + + /* + * Remember what types of addresses we are interested in. + */ + find->options = options; + find->flags |= wanted_addresses; + if (FIND_WANTEVENT(find)) { + REQUIRE(task != NULL); + } + + /* + * Try to see if we know anything about this name at all. + */ + bucket = DNS_ADB_INVALIDBUCKET; + adbname = find_name_and_lock(adb, name, find->options, &bucket); + if (adb->name_sd[bucket]) { + DP(DEF_LEVEL, + "dns_adb_createfind: returning ISC_R_SHUTTINGDOWN"); + free_adbfind(adb, &find); + 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_adbfind(adb, &find); + result = ISC_R_NOMEMORY; + goto out; + } + link_name(adb, bucket, adbname); + if (FIND_HINTOK(find)) + adbname->flags |= NAME_HINT_OK; + if (FIND_GLUEOK(find)) + adbname->flags |= NAME_GLUE_OK; + } + + /* + * Expire old entries, etc. + */ + check_expire_namehooks(adbname, now); + + /* + * Do we know that the name is an alias? + */ + if (!EXPIRE_OK(adbname->expire_target, now)) { + /* + * Yes, it is. + */ + DP(DEF_LEVEL, + "dns_adb_createfind: name %p is an alias (cached)", + adbname); + alias = ISC_TRUE; + goto post_copy; + } + + /* + * Try to populate the name from the database and/or + * start fetches. + */ + if (!NAME_HAS_V4(adbname) && !NAME_FETCH_V4(adbname) + && EXPIRE_OK(adbname->expire_v4, now) + && WANT_INET(wanted_addresses)) { + result = dbfind_name(adbname, now, dns_rdatatype_a); + if (result == ISC_R_SUCCESS) { + DP(DEF_LEVEL, + "dns_adb_createfind: Found A for name %p in db", + adbname); + goto v6; + } + + /* + * Did we get a CNAME or DNAME? + */ + if (result == DNS_R_ALIAS) { + DP(DEF_LEVEL, + "dns_adb_createfind: name %p is an alias", + adbname); + alias = ISC_TRUE; + goto post_copy; + } + + /* + * Listen to negative cache hints, and don't start + * another query. + */ + if (NCACHE_RESULT(result) || AUTH_NX(result)) + goto v6; + + wanted_fetches |= DNS_ADBFIND_INET; + } + + v6: + if (!NAME_HAS_V6(adbname) && !NAME_FETCH_V6(adbname) + && EXPIRE_OK(adbname->expire_v6, now) + && WANT_INET6(wanted_addresses)) { + result = dbfind_a6(adbname, now); + if (result == ISC_R_SUCCESS) { + DP(DEF_LEVEL, + "dns_adb_createfind: Found A6 for name %p", + adbname); + goto fetch; + } + + /* + * Did we get a CNAME or DNAME? + */ + if (result == DNS_R_ALIAS) { + DP(DEF_LEVEL, + "dns_adb_createfind: name %p is an alias", + adbname); + alias = ISC_TRUE; + goto post_copy; + } + + /* + * Listen to negative cache hints, and don't start + * another query. + */ + if (NCACHE_RESULT(result) || AUTH_NX(result)) + goto fetch; + + wanted_fetches |= DNS_ADBFIND_INET6; + } + + fetch: + if (wanted_fetches != 0 && + (!FIND_AVOIDFETCHES(find) || wanted_addresses == wanted_fetches)) { + /* + * We're missing at least one address family. Either the + * caller hasn't instructed us to avoid fetches, or we don't + * know anything about any of the address families that would + * be acceptable so we have to launch fetches. + */ + + if (FIND_STARTATROOT(find)) + start_at_root = ISC_TRUE; + + /* + * Start V4. + */ + if (WANT_INET(wanted_fetches) && + fetch_name_v4(adbname, start_at_root) == ISC_R_SUCCESS) { + DP(DEF_LEVEL, + "dns_adb_createfind: Started A fetch for name %p", + adbname); + } + + /* + * Start V6. + */ + if (WANT_INET6(wanted_fetches) && + fetch_name_a6(adbname, start_at_root) == ISC_R_SUCCESS) { + DP(DEF_LEVEL, + "dns_adb_createfind: Started A6 fetch for name %p", + adbname); + } + } + + /* + * Run through the name and copy out the bits we are + * interested in. + */ + copy_namehook_lists(adb, find, zone, adbname, now); + + post_copy: + if (NAME_FETCH_V4(adbname)) + query_pending |= DNS_ADBFIND_INET; + if (NAME_FETCH_V6(adbname)) + query_pending |= DNS_ADBFIND_INET6; + + /* + * Attach to the name's query list if there are queries + * already running, and we have been asked to. + */ + want_event = ISC_TRUE; + if (!FIND_WANTEVENT(find)) + want_event = ISC_FALSE; + if (FIND_WANTEMPTYEVENT(find) && FIND_HAS_ADDRS(find)) + want_event = ISC_FALSE; + if ((wanted_addresses & query_pending) == 0) + want_event = ISC_FALSE; + if (alias) + want_event = ISC_FALSE; + if (want_event) { + find->adbname = adbname; + find->name_bucket = bucket; + ISC_LIST_APPEND(adbname->finds, find, plink); + find->query_pending = (query_pending & wanted_addresses); + find->flags &= ~DNS_ADBFIND_ADDRESSMASK; + find->flags |= (find->query_pending & DNS_ADBFIND_ADDRESSMASK); + DP(DEF_LEVEL, "createfind: attaching find %p to adbname %p", + find, adbname); + } else { + /* + * Remove the flag so the caller knows there will never + * be an event, and set internal flags to fake that + * the event was sent and freed, so dns_adb_destroyfind() will + * do the right thing. + */ + find->query_pending = (query_pending & wanted_addresses); + find->options &= ~DNS_ADBFIND_WANTEVENT; + find->flags |= (FIND_EVENT_SENT | FIND_EVENT_FREED); + find->flags &= ~DNS_ADBFIND_ADDRESSMASK; + } + + find->partial_result |= (adbname->partial_result & wanted_addresses); + if (alias) { + if (target != NULL) { + result = dns_name_concatenate(&adbname->target, NULL, + target, NULL); + if (result != ISC_R_SUCCESS) + goto out; + } + result = DNS_R_ALIAS; + } else + result = ISC_R_SUCCESS; + + out: + if (find != NULL) { + *findp = find; + + if (want_event) { + isc_task_t *taskp; + + INSIST((find->flags & DNS_ADBFIND_ADDRESSMASK) != 0); + taskp = NULL; + isc_task_attach(task, &taskp); + find->event.sender = taskp; + find->event.action = action; + find->event.arg = arg; + } + } + + /* dns_adb_dumpfind(find, stderr); */ + + if (bucket != DNS_ADB_INVALIDBUCKET) + UNLOCK(&adb->namelocks[bucket]); + + return (result); +} + +void +dns_adb_destroyfind(dns_adbfind_t **findp) +{ + dns_adbfind_t *find; + dns_adbentry_t *entry; + dns_adbaddrinfo_t *ai; + int bucket; + dns_adb_t *adb; + + REQUIRE(findp != NULL && DNS_ADBFIND_VALID(*findp)); + find = *findp; + *findp = NULL; + + LOCK(&find->lock); + + DP(DEF_LEVEL, "dns_adb_destroyfind on find %p", find); + + adb = find->adb; + REQUIRE(DNS_ADB_VALID(adb)); + + REQUIRE(FIND_EVENTFREED(find)); + + bucket = find->name_bucket; + INSIST(bucket == DNS_ADB_INVALIDBUCKET); + + UNLOCK(&find->lock); + + /* + * The find doesn't exist on any list, and nothing is locked. + * Return the find to the memory pool, and decrement the adb's + * reference count. + */ + ai = ISC_LIST_HEAD(find->list); + while (ai != NULL) { + ISC_LIST_UNLINK(find->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(find->list); + } + + /* + * WARNING: The find is freed with the adb locked. This is done + * to avoid a race condition where we free the find, some other + * thread tests to see if it should be destroyed, detects it should + * be, destroys it, and then we try to lock it for our check, but the + * lock is destroyed. + */ + LOCK(&adb->lock); + free_adbfind(adb, &find); + check_exit(adb); + UNLOCK(&adb->lock); +} + +void +dns_adb_cancelfind(dns_adbfind_t *find) +{ + isc_event_t *ev; + isc_task_t *task; + dns_adb_t *adb; + int bucket; + int unlock_bucket; + + LOCK(&find->lock); + + DP(DEF_LEVEL, "dns_adb_cancelfind on find %p", find); + + adb = find->adb; + REQUIRE(DNS_ADB_VALID(adb)); + + REQUIRE(!FIND_EVENTFREED(find)); + REQUIRE(FIND_WANTEVENT(find)); + + bucket = find->name_bucket; + if (bucket == DNS_ADB_INVALIDBUCKET) + goto cleanup; + + /* + * We need to get the adbname's lock to unlink the find. + */ + unlock_bucket = bucket; + violate_locking_hierarchy(&find->lock, &adb->namelocks[unlock_bucket]); + bucket = find->name_bucket; + if (bucket != DNS_ADB_INVALIDBUCKET) { + ISC_LIST_UNLINK(find->adbname->finds, find, plink); + find->adbname = NULL; + find->name_bucket = DNS_ADB_INVALIDBUCKET; + } + UNLOCK(&adb->namelocks[unlock_bucket]); + bucket = DNS_ADB_INVALIDBUCKET; + + cleanup: + + if (!FIND_EVENTSENT(find)) { + ev = &find->event; + task = ev->sender; + ev->sender = find; + ev->type = DNS_EVENT_ADBCANCELED; + ev->destroy = event_free; + ev->destroy_arg = find; + + DP(DEF_LEVEL, "Sending event %p to task %p for find %p", + ev, task, find); + + isc_task_sendanddetach(&task, &ev); + } + + UNLOCK(&find->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; + isc_stdtime_t now; + + isc_stdtime_get(&now); + + fprintf(f, "ADB %p DUMP:\n", adb); + fprintf(f, "erefcnt %u, irefcnt %u, finds out %u\n", + adb->erefcnt, adb->irefcnt, + isc_mempool_getallocated(adb->nhmp)); + + for (i = 0 ; i < NBUCKETS ; i++) + LOCK(&adb->namelocks[i]); + for (i = 0 ; i < NBUCKETS ; i++) + LOCK(&adb->entrylocks[i]); + + /* + * Dump the names + */ + fprintf(f, "Names:\n"); + for (i = 0 ; i < NBUCKETS ; 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 (flags %08x)\n", + name, name->flags); + if (!DNS_ADBNAME_VALID(name)) + fprintf(f, "\tMAGIC %08x\n", name->magic); + fprintf(f, "\texpiry ["); + if (name->expire_v4 == INT_MAX) + fprintf(f, "inf "); + else + fprintf(f, "%d ", name->expire_v4 - now); + if (name->expire_v6 == INT_MAX) + fprintf(f, "inf "); + else + fprintf(f, "%d ", name->expire_v6 - now); + if (name->expire_target == INT_MAX) + fprintf(f, "inf] "); + else + fprintf(f, "%d] ", name->expire_target - now); + print_dns_name(f, &name->name); + if (dns_name_countlabels(&name->target) > 0) { + fprintf(f, "\t\t alias for "); + print_dns_name(f, &name->target); + } + fprintf(f, "\n"); + print_namehook_list(f, name); + print_fetch_list(f, name); + print_find_list(f, name); + fprintf(f, "\n"); + + name = ISC_LIST_NEXT(name, plink); + } + } + + /* + * Dump the entries + */ + fprintf(f, "Entries:\n"); + for (i = 0 ; i < NBUCKETS ; 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 < NBUCKETS ; i++) + UNLOCK(&adb->entrylocks[i]); + for (i = 0 ; i < NBUCKETS ; i++) + UNLOCK(&adb->namelocks[i]); +} + +void +dns_adb_dumpfind(dns_adbfind_t *find, 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(&find->lock); + + fprintf(f, "Find %p\n", find); + fprintf(f, "\tqpending %08x partial %08x options %08x flags %08x\n", + find->query_pending, find->partial_result, + find->options, find->flags); + fprintf(f, "\tname_bucket %d, name %p, event sender %p\n", + find->name_bucket, find->adbname, find->event.sender); + + ai = ISC_LIST_HEAD(find->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(&find->lock); +} + +static void +print_dns_name(FILE *f, dns_name_t *name) +{ + char buf[1024]; + isc_buffer_t b; + isc_region_t r; + + INSIST(f != NULL); + + isc_buffer_init(&b, buf, sizeof buf, ISC_BUFFERTYPE_TEXT); + + if (dns_name_totext(name, ISC_FALSE, &b) == ISC_R_SUCCESS) { + isc_buffer_used(&b, &r); + fprintf(f, "%.*s", (int)r.length, r.base); + } +} + +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(V4) %p -> entry %p\n", nh, nh->entry); + nh = ISC_LIST_NEXT(nh, plink); + } + nh = ISC_LIST_HEAD(n->v6); + while (nh != NULL) { + fprintf(f, "\t\tHook(V6) %p -> entry %p\n", nh, nh->entry); + nh = ISC_LIST_NEXT(nh, plink); + } +} + +static inline void +print_fetch(FILE *f, dns_adbfetch_t *ft, char *type) +{ + fprintf(f, "\t\tFetch(%s): %p -> { nh %p, entry %p, fetch %p }\n", + type, ft, ft->namehook, ft->entry, ft->fetch); +} + +static inline void +print_fetch6(FILE *f, dns_adbfetch6_t *ft) +{ + fprintf(f, "\t\tFetch(A6): %p -> { nh %p, entry %p, fetch %p }\n", + ft, ft->namehook, ft->entry, ft->fetch); +} + +static void +print_fetch_list(FILE *f, dns_adbname_t *n) +{ + dns_adbfetch6_t *fetch6; + + if (NAME_FETCH_A(n)) + print_fetch(f, n->fetch_a, "A"); + if (NAME_FETCH_AAAA(n)) + print_fetch(f, n->fetch_aaaa, "AAAA"); + + fetch6 = ISC_LIST_HEAD(n->fetches_a6); + while (fetch6 != NULL) { + print_fetch6(f, fetch6); + fetch6 = ISC_LIST_NEXT(fetch6, plink); + } +} + +static void +print_find_list(FILE *f, dns_adbname_t *name) +{ + dns_adbfind_t *find; + + find = ISC_LIST_HEAD(name->finds); + while (find != NULL) { + dns_adb_dumpfind(find, f); + find = ISC_LIST_NEXT(find, plink); + } +} + +static isc_result_t +dbfind_name(dns_adbname_t *adbname, isc_stdtime_t now, + dns_rdatatype_t rdtype) +{ + isc_result_t result; + dns_rdataset_t rdataset; + dns_adb_t *adb; + dns_fixedname_t foundname; + dns_name_t *fname; + + INSIST(DNS_ADBNAME_VALID(adbname)); + adb = adbname->adb; + INSIST(DNS_ADB_VALID(adb)); + INSIST(rdtype == dns_rdatatype_a || rdtype == dns_rdatatype_aaaa); + + dns_fixedname_init(&foundname); + fname = dns_fixedname_name(&foundname); + dns_rdataset_init(&rdataset); + + result = dns_view_find(adb->view, &adbname->name, rdtype, now, + NAME_GLUEOK(adbname), NAME_HINTOK(adbname), + fname, &rdataset, NULL); + + switch (result) { + case DNS_R_GLUE: + case DNS_R_HINT: + case DNS_R_SUCCESS: + /* + * Found in the database. Even if we can't copy out + * any information, return success, or else a fetch + * will be made, which will only make things worse. + */ + result = import_rdataset(adbname, &rdataset, now); + break; + case DNS_R_NXDOMAIN: + case DNS_R_NXRRSET: + /* + * We're authoritative and the data doesn't exist. + * Make up a negative cache entry so we don't ask again + * for a while. + * + * XXXRTH What time should we use? I'm putting in 30 seconds + * for now. + */ + if (rdtype == dns_rdatatype_a) { + adbname->expire_v4 = now + 30; + DP(NCACHE_LEVEL, + "adb name %p: Caching auth negative entry for A", + adbname); + } else { + DP(NCACHE_LEVEL, + "adb name %p: Caching auth negative entry for AAAA", + adbname); + adbname->expire_v6 = now + 30; + } + break; + case DNS_R_NCACHENXDOMAIN: + case DNS_R_NCACHENXRRSET: + /* + * We found a negative cache entry. Pull the TTL from it + * so we won't ask again for a while. + */ + rdataset.ttl = ISC_MAX(rdataset.ttl, ADB_CACHE_MINIMUM); + if (rdtype == dns_rdatatype_a) { + adbname->expire_v4 = rdataset.ttl + now; + DP(NCACHE_LEVEL, + "adb name %p: Caching negative entry for A (ttl %u)", + adbname, rdataset.ttl); + } else { + DP(NCACHE_LEVEL, + "adb name %p: Caching negative entry for AAAA (ttl %u)", + adbname, rdataset.ttl); + adbname->expire_v6 = rdataset.ttl + now; + } + break; + case DNS_R_CNAME: + case DNS_R_DNAME: + /* + * Clear the hint and glue flags, so this will match + * more often. + */ + adbname->flags &= ~(DNS_ADBFIND_GLUEOK | DNS_ADBFIND_HINTOK); + + rdataset.ttl = ISC_MAX(rdataset.ttl, ADB_CACHE_MINIMUM); + clean_target(adb, &adbname->target); + adbname->expire_target = INT_MAX; + result = set_target(adb, &adbname->name, fname, &rdataset, + &adbname->target); + if (result == ISC_R_SUCCESS) { + result = DNS_R_ALIAS; + DP(NCACHE_LEVEL, + "adb name %p: caching alias target", + adbname); + adbname->expire_target = rdataset.ttl + now; + } + break; + } + + if (dns_rdataset_isassociated(&rdataset)) + dns_rdataset_disassociate(&rdataset); + + return (result); +} + +static isc_result_t +dbfind_a6(dns_adbname_t *adbname, isc_stdtime_t now) +{ + isc_result_t result; + dns_rdataset_t rdataset; + dns_adb_t *adb; + dns_a6context_t a6ctx; + dns_fixedname_t foundname; + dns_name_t *fname; + + INSIST(DNS_ADBNAME_VALID(adbname)); + adb = adbname->adb; + INSIST(DNS_ADB_VALID(adb)); + INSIST(!NAME_FETCH_V6(adbname)); + + result = ISC_R_UNEXPECTED; + + dns_fixedname_init(&foundname); + fname = dns_fixedname_name(&foundname); + dns_rdataset_init(&rdataset); + + result = dns_view_find(adb->view, &adbname->name, dns_rdatatype_a6, + now, NAME_GLUEOK(adbname), NAME_HINTOK(adbname), + fname, &rdataset, NULL); + + switch (result) { + case DNS_R_GLUE: + case DNS_R_HINT: + case DNS_R_SUCCESS: + /* + * Start a6 chain follower. There is no need to poke people + * who might be waiting, since this is call requires there + * are none. + */ + dns_a6_init(&a6ctx, a6find, NULL, import_a6, + a6missing, adbname); + (void)dns_a6_foreach(&a6ctx, &rdataset, now); + result = ISC_R_SUCCESS; + break; + case DNS_R_NXDOMAIN: + case DNS_R_NXRRSET: + /* + * We're authoritative and the data doesn't exist. + * Make up a negative cache entry so we don't ask again + * for a while. + * + * XXXRTH What time should we use? I'm putting in 30 seconds + * for now. + */ + DP(NCACHE_LEVEL, + "adb name %p: Caching auth negative entry for AAAA", + adbname); + adbname->expire_v6 = now + 30; + break; + case DNS_R_NCACHENXDOMAIN: + case DNS_R_NCACHENXRRSET: + /* + * We found a negative cache entry. Pull the TTL from it + * so we won't ask again for a while. + */ + DP(NCACHE_LEVEL, + "adb name %p: Caching negative entry for A6 (ttl %u)", + adbname, rdataset.ttl); + adbname->expire_v6 = ISC_MIN(rdataset.ttl + now, + adbname->expire_v6); + break; + case DNS_R_CNAME: + case DNS_R_DNAME: + rdataset.ttl = ISC_MAX(rdataset.ttl, ADB_CACHE_MINIMUM); + clean_target(adb, &adbname->target); + adbname->expire_target = INT_MAX; + result = set_target(adb, &adbname->name, fname, &rdataset, + &adbname->target); + if (result == ISC_R_SUCCESS) { + result = DNS_R_ALIAS; + DP(NCACHE_LEVEL, + "adb name %p: caching alias target", + adbname); + adbname->expire_target = rdataset.ttl + now; + } + break; + } + + if (dns_rdataset_isassociated(&rdataset)) + dns_rdataset_disassociate(&rdataset); + + return (result); +} + +static void +fetch_callback(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; + unsigned int address_type; + isc_boolean_t want_check_exit = ISC_FALSE; + + (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)); + + bucket = name->lock_bucket; + LOCK(&adb->namelocks[bucket]); + + INSIST(NAME_FETCH_A(name) || NAME_FETCH_AAAA(name)); + address_type = 0; + if (NAME_FETCH_A(name) && (name->fetch_a->fetch == dev->fetch)) { + address_type = DNS_ADBFIND_INET; + fetch = name->fetch_a; + name->fetch_a = NULL; + } else if (NAME_FETCH_AAAA(name) + && (name->fetch_aaaa->fetch == dev->fetch)) { + address_type = DNS_ADBFIND_INET6; + fetch = name->fetch_aaaa; + name->fetch_aaaa = NULL; + } + INSIST(address_type != 0); + + dns_resolver_destroyfetch(&fetch->fetch); + dev->fetch = NULL; + + ev_status = DNS_EVENT_ADBNOMOREADDRESSES; + + /* + * 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(name)) { + free_adbfetch(adb, &fetch); + isc_event_free(&ev); + + kill_name(&name, DNS_EVENT_ADBCANCELED); + + /* + * If we're shutting down and this bucket is empty, we need + * to call check_exit() to see if we're done. + */ + if (adb->name_sd[bucket] && adb->name_refcnt[bucket] == 0) + want_check_exit = ISC_TRUE; + + UNLOCK(&adb->namelocks[bucket]); + + if (want_check_exit) { + LOCK(&adb->lock); + check_exit(adb); + UNLOCK(&adb->lock); + } + + return; + } + + isc_stdtime_get(&now); + + /* + * If we got a negative cache response, remember it. + */ + if (NCACHE_RESULT(dev->result)) { + dev->rdataset->ttl = ISC_MAX(dev->rdataset->ttl, + ADB_CACHE_MINIMUM); + if (address_type == DNS_ADBFIND_INET) { + DP(NCACHE_LEVEL, "adb fetch name %p: " + "Caching negative entry for A (ttl %u)", + name, dev->rdataset->ttl); + name->expire_v4 = ISC_MIN(name->expire_v4, + dev->rdataset->ttl + now); + } else { + DP(NCACHE_LEVEL, "adb fetch name %p: " + "Caching negative entry for AAAA (ttl %u)", + name, dev->rdataset->ttl); + name->expire_v6 = ISC_MIN(name->expire_v6, + dev->rdataset->ttl + now); + } + goto out; + } + + /* + * Handle CNAME/DNAME. + */ + if (dev->result == DNS_R_CNAME || dev->result == DNS_R_DNAME) { + dev->rdataset->ttl = ISC_MAX(dev->rdataset->ttl, + ADB_CACHE_MINIMUM); + clean_target(adb, &name->target); + name->expire_target = INT_MAX; + result = set_target(adb, &name->name, + dns_fixedname_name(&dev->foundname), + dev->rdataset, + &name->target); + if (result == ISC_R_SUCCESS) { + DP(NCACHE_LEVEL, + "adb fetch name %p: caching alias target", + name); + name->expire_target = dev->rdataset->ttl + now; + } + goto check_result; + } + + /* + * Did we get back junk? If so, and there are no more fetches + * sitting out there, tell all the finds about it. + */ + if (dev->result != ISC_R_SUCCESS) { + /* XXXMLG Don't pound on bad servers. */ + if (address_type == DNS_ADBFIND_INET) + name->expire_v4 = ISC_MIN(name->expire_v4, now + 300); + else + name->expire_v6 = ISC_MIN(name->expire_v6, now + 300); + DP(1, "got junk in fetch for name %p (%s)", + name, isc_result_totext(dev->result)); + + goto out; + } + + /* + * We got something potentially useful. + */ + result = import_rdataset(name, &fetch->rdataset, now); + + check_result: + if (result == ISC_R_SUCCESS) + ev_status = DNS_EVENT_ADBMOREADDRESSES; + + out: + free_adbfetch(adb, &fetch); + isc_event_free(&ev); + + clean_finds_at_name(name, ev_status, address_type); + + UNLOCK(&adb->namelocks[bucket]); +} + +static void +fetch_callback_a6(isc_task_t *task, isc_event_t *ev) +{ + dns_fetchevent_t *dev; + dns_adbname_t *name; + dns_adb_t *adb; + dns_adbfetch6_t *fetch; + int bucket; + isc_stdtime_t now; + isc_result_t result; + isc_boolean_t want_check_exit = ISC_FALSE; + + (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)); + + bucket = name->lock_bucket; + LOCK(&adb->namelocks[bucket]); + + INSIST(!NAME_NEEDSPOKE(name)); + + for (fetch = ISC_LIST_HEAD(name->fetches_a6); + fetch != NULL; + fetch = ISC_LIST_NEXT(fetch, plink)) + if (fetch->fetch == dev->fetch) + break; + INSIST(fetch != NULL); + ISC_LIST_UNLINK(name->fetches_a6, fetch, plink); + + DP(ENTER_LEVEL, "ENTER: fetch_callback_a6() name %p", name); + + dns_resolver_destroyfetch(&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(name)) { + free_adbfetch6(adb, &fetch); + isc_event_free(&ev); + + kill_name(&name, DNS_EVENT_ADBCANCELED); + + /* + * If we're shutting down and this bucket is empty, we need + * to call check_exit() to see if we're done. + */ + if (adb->name_sd[bucket] && adb->name_refcnt[bucket] == 0) + want_check_exit = ISC_TRUE; + + UNLOCK(&adb->namelocks[bucket]); + + if (want_check_exit) { + LOCK(&adb->lock); + check_exit(adb); + UNLOCK(&adb->lock); + } + + return; + } + + isc_stdtime_get(&now); + + /* + * If the A6 query didn't succeed, and this is the first query + * in the A6 chain, try AAAA records instead. For later failures, + * don't do this. + */ + if (dev->result != ISC_R_SUCCESS) { + DP(DEF_LEVEL, "name %p: A6 failed, result %u", + name, dev->result); + + /* + * If we got a negative cache response, remember it. + */ + if (NCACHE_RESULT(dev->result)) { + dev->rdataset->ttl = ISC_MAX(dev->rdataset->ttl, + ADB_CACHE_MINIMUM); + DP(NCACHE_LEVEL, "adb fetch name %p: " + "Caching negative entry for A6 (ttl %u)", + name, dev->rdataset->ttl); + name->expire_v6 = ISC_MIN(name->expire_v6, + dev->rdataset->ttl + now); + } + + /* + * Handle CNAME/DNAME. + */ + if (dev->result == DNS_R_CNAME || dev->result == DNS_R_DNAME) { + dev->rdataset->ttl = ISC_MAX(dev->rdataset->ttl, + ADB_CACHE_MINIMUM); + clean_target(adb, &name->target); + name->expire_target = INT_MAX; + result = set_target(adb, &name->name, + dns_fixedname_name(&dev->foundname), + dev->rdataset, + &name->target); + if (result == ISC_R_SUCCESS) { + DP(NCACHE_LEVEL, + "adb A6 fetch name %p: caching alias target", + name); + name->expire_target = dev->rdataset->ttl + now; + if (FETCH_FIRSTA6(fetch)) { + /* + * Make this name 'pokeable', since + * we've learned that this name is an + * alias. + */ + name->flags |= NAME_NEEDS_POKE; + } + } + goto out; + } + + if (FETCH_FIRSTA6(fetch) && !NAME_HAS_V6(name)) { + DP(DEF_LEVEL, + "name %p: A6 query failed, starting AAAA", name); + + /* + * Since this is the very first fetch, and it + * failed, we know there are no more running. + */ + result = dbfind_name(name, now, dns_rdatatype_aaaa); + if (result == ISC_R_SUCCESS) { + DP(DEF_LEVEL, + "name %p: callback_a6: Found AAAA for", + name); + name->flags |= NAME_NEEDS_POKE; + goto out; + } + + /* + * Listen to negative cache hints, and don't start + * another query. + */ + if (NCACHE_RESULT(result) || AUTH_NX(result)) + goto out; + + /* + * Try to start fetches for AAAA. + */ + result = fetch_name_aaaa(name); + if (result == ISC_R_SUCCESS) { + DP(DEF_LEVEL, + "name %p: callback_a6: Started AAAA fetch", + name); + goto out; + } + } + + goto out; + } + + /* + * We got something potentially useful. Run the A6 chain + * follower on this A6 rdataset. + */ + + fetch->a6ctx.chains = name->chains; + (void)dns_a6_foreach(&fetch->a6ctx, dev->rdataset, now); + + out: + free_adbfetch6(adb, &fetch); + isc_event_free(&ev); + + if (NAME_NEEDSPOKE(name)) + clean_finds_at_name(name, DNS_EVENT_ADBMOREADDRESSES, + DNS_ADBFIND_INET6); + else if (!NAME_FETCH_V6(name)) + clean_finds_at_name(name, DNS_EVENT_ADBNOMOREADDRESSES, + DNS_ADBFIND_INET6); + + name->flags &= ~NAME_NEEDS_POKE; + + UNLOCK(&adb->namelocks[bucket]); + + return; +} + +static isc_result_t +fetch_name_v4(dns_adbname_t *adbname, isc_boolean_t start_at_root) +{ + isc_result_t result; + dns_adbfetch_t *fetch; + dns_adb_t *adb; + dns_name_t *name; + + INSIST(DNS_ADBNAME_VALID(adbname)); + adb = adbname->adb; + INSIST(DNS_ADB_VALID(adb)); + + INSIST(!NAME_FETCH_V4(adbname)); + + if (start_at_root) { + DP(50, "fetch_name_v4: starting at DNS root for name %p", + adbname); + name = dns_rootname; + } else + name = &adbname->name; + + 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, + NULL, NULL, NULL, 0, + adb->task, fetch_callback, + adbname, &fetch->rdataset, NULL, + &fetch->fetch); + if (result != ISC_R_SUCCESS) + goto cleanup; + + adbname->fetch_a = fetch; + fetch = NULL; /* keep us from cleaning this up below */ + + cleanup: + if (fetch != NULL) + free_adbfetch(adb, &fetch); + + return (result); +} + +static isc_result_t +fetch_name_aaaa(dns_adbname_t *adbname) +{ + isc_result_t result; + dns_adbfetch_t *fetch; + dns_adb_t *adb; + + INSIST(DNS_ADBNAME_VALID(adbname)); + adb = adbname->adb; + INSIST(DNS_ADB_VALID(adb)); + + INSIST(!NAME_FETCH_AAAA(adbname)); + + fetch = new_adbfetch(adb); + if (fetch == NULL) { + result = ISC_R_NOMEMORY; + goto cleanup; + } + + result = dns_resolver_createfetch(adb->view->resolver, &adbname->name, + dns_rdatatype_aaaa, + NULL, NULL, NULL, 0, + adb->task, fetch_callback, + adbname, &fetch->rdataset, NULL, + &fetch->fetch); + if (result != ISC_R_SUCCESS) + goto cleanup; + + adbname->fetch_aaaa = fetch; + fetch = NULL; /* keep us from cleaning this up below */ + + cleanup: + if (fetch != NULL) + free_adbfetch(adb, &fetch); + + return (result); +} + +static isc_result_t +fetch_name_a6(dns_adbname_t *adbname, isc_boolean_t start_at_root) +{ + isc_result_t result; + dns_adbfetch6_t *fetch; + dns_adb_t *adb; + dns_name_t *name; + + INSIST(DNS_ADBNAME_VALID(adbname)); + adb = adbname->adb; + INSIST(DNS_ADB_VALID(adb)); + + INSIST(!NAME_FETCH_V6(adbname)); + + if (start_at_root) { + DP(50, "fetch_name_a6: starting at DNS root for name %p", + adbname); + name = dns_rootname; + } else + name = &adbname->name; + + fetch = new_adbfetch6(adb, adbname, NULL); + if (fetch == NULL) { + result = ISC_R_NOMEMORY; + goto cleanup; + } + fetch->flags |= FETCH_FIRST_A6; + + result = dns_resolver_createfetch(adb->view->resolver, &adbname->name, + dns_rdatatype_a6, + NULL, NULL, NULL, 0, + adb->task, fetch_callback_a6, + adbname, &fetch->rdataset, NULL, + &fetch->fetch); + if (result != ISC_R_SUCCESS) + goto cleanup; + + ISC_LIST_APPEND(adbname->fetches_a6, fetch, plink); + fetch = NULL; /* keep us from cleaning this up below */ + + cleanup: + if (fetch != NULL) + free_adbfetch6(adb, &fetch); + + return (result); +} + +/* XXXMLG + * Needs to take a find argument and an address info, no zone or adb, since + * these can be extracted from the find itself. + */ +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)); + REQUIRE(factor <= 10); + + bucket = addr->entry->lock_bucket; + LOCK(&adb->entrylocks[bucket]); + + new_srtt = (addr->entry->srtt / 10 * factor) + + (rtt / 10 * (10 - factor)); + + addr->entry->srtt = new_srtt; + addr->srtt = new_srtt; + + UNLOCK(&adb->entrylocks[bucket]); +} + +void +dns_adb_changeflags(dns_adb_t *adb, dns_adbaddrinfo_t *addr, + unsigned int bits, unsigned int mask) +{ + int bucket; + + REQUIRE(DNS_ADB_VALID(adb)); + REQUIRE(DNS_ADBADDRINFO_VALID(addr)); + + bucket = addr->entry->lock_bucket; + LOCK(&adb->entrylocks[bucket]); + + addr->entry->flags = (addr->entry->flags & ~mask) | (bits & mask); + /* + * Note that we do not update the other bits in addr->flags with + * the most recent values from addr->entry->flags. + * + * XXXRTH I think this is what we want, because otherwise flags + * that the caller didn't ask to change could be updated. + */ + addr->flags = (addr->flags & ~mask) | (bits & mask); + + UNLOCK(&adb->entrylocks[bucket]); +} + +isc_result_t +dns_adb_findaddrinfo(dns_adb_t *adb, isc_sockaddr_t *sa, + dns_adbaddrinfo_t **addrp) +{ + int bucket; + dns_adbentry_t *entry; + dns_adbaddrinfo_t *addr; + isc_result_t result; + + REQUIRE(DNS_ADB_VALID(adb)); + REQUIRE(addrp != NULL && *addrp == NULL); + + result = ISC_R_SUCCESS; + bucket = DNS_ADB_INVALIDBUCKET; + entry = find_entry_and_lock(adb, sa, &bucket); + if (adb->entry_sd[bucket]) { + result = ISC_R_SHUTTINGDOWN; + goto unlock; + } + if (entry == NULL) { + /* + * We don't know anything about this address. + */ + entry = new_adbentry(adb); + if (entry == NULL) { + result = ISC_R_NOMEMORY; + goto unlock; + } + entry->sockaddr = *sa; + link_entry(adb, bucket, entry); + DP(50, "findaddrinfo: new entry %p", entry); + } else + DP(50, "findaddrinfo: found entry %p", entry); + + addr = new_adbaddrinfo(adb, entry); + if (addr != NULL) { + inc_entry_refcnt(adb, entry, ISC_FALSE); + *addrp = addr; + } + + unlock: + UNLOCK(&adb->entrylocks[bucket]); + + return (result); +} + +void +dns_adb_freeaddrinfo(dns_adb_t *adb, dns_adbaddrinfo_t **addrp) +{ + dns_adbaddrinfo_t *addr; + dns_adbentry_t *entry; + int bucket; + isc_stdtime_t now; + isc_boolean_t want_check_exit = ISC_FALSE; + + REQUIRE(DNS_ADB_VALID(adb)); + REQUIRE(addrp != NULL); + addr = *addrp; + REQUIRE(DNS_ADBADDRINFO_VALID(addr)); + entry = addr->entry; + REQUIRE(DNS_ADBENTRY_VALID(entry)); + + isc_stdtime_get(&now); + + *addrp = NULL; + + bucket = addr->entry->lock_bucket; + LOCK(&adb->entrylocks[bucket]); + + entry->expires = now + 1800; /* XXXRTH */ + + dec_entry_refcnt(adb, entry, ISC_FALSE); + if (adb->entry_sd[bucket] && adb->entry_refcnt[bucket] == 0) + want_check_exit = ISC_TRUE; + + UNLOCK(&adb->entrylocks[bucket]); + + addr->entry = NULL; + addr->sockaddr = NULL; + free_adbaddrinfo(adb, &addr); + + if (want_check_exit) { + LOCK(&adb->lock); + check_exit(adb); + UNLOCK(&adb->lock); + } +} |