/* * Copyright (C) 2004-2008 Internet Systems Consortium, Inc. ("ISC") * Copyright (C) 1999-2003 Internet Software Consortium. * * Permission to use, copy, modify, and/or 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 ISC DISCLAIMS ALL WARRANTIES WITH * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY * AND FITNESS. IN NO EVENT SHALL ISC 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. */ /* $Id: adb.c,v 1.243 2008/10/17 03:23:13 marka Exp $ */ /*! \file * * \note * 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. * */ #include #include #include #include #include #include /* Required for HP/UX (and others?) */ #include #include #include #include #include #include #include #include #include #include #include #include #include #define DNS_ADB_MAGIC ISC_MAGIC('D', 'a', 'd', 'b') #define DNS_ADB_VALID(x) ISC_MAGIC_VALID(x, DNS_ADB_MAGIC) #define DNS_ADBNAME_MAGIC ISC_MAGIC('a', 'd', 'b', 'N') #define DNS_ADBNAME_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBNAME_MAGIC) #define DNS_ADBNAMEHOOK_MAGIC ISC_MAGIC('a', 'd', 'N', 'H') #define DNS_ADBNAMEHOOK_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBNAMEHOOK_MAGIC) #define DNS_ADBLAMEINFO_MAGIC ISC_MAGIC('a', 'd', 'b', 'Z') #define DNS_ADBLAMEINFO_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBLAMEINFO_MAGIC) #define DNS_ADBENTRY_MAGIC ISC_MAGIC('a', 'd', 'b', 'E') #define DNS_ADBENTRY_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBENTRY_MAGIC) #define DNS_ADBFETCH_MAGIC ISC_MAGIC('a', 'd', 'F', '4') #define DNS_ADBFETCH_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBFETCH_MAGIC) #define DNS_ADBFETCH6_MAGIC ISC_MAGIC('a', 'd', 'F', '6') #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? */ #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/AAAA records * if the zone has extremely low TTLs. */ #define ADB_CACHE_MINIMUM 10 /*%< seconds */ #define ADB_CACHE_MAXIMUM 86400 /*%< seconds (86400 = 24 hours) */ #define ADB_ENTRY_WINDOW 1800 /*%< seconds */ /*% * The period in seconds after which an ADB name entry is regarded as stale * and forced to be cleaned up. * TODO: This should probably be configurable at run-time. */ #ifndef ADB_STALE_MARGIN #define ADB_STALE_MARGIN 1800 #endif #define FREE_ITEMS 64 /*%< free count for memory pools */ #define FILL_COUNT 16 /*%< fill count for memory pools */ #define DNS_ADB_INVALIDBUCKET (-1) /*%< invalid bucket address */ #define DNS_ADB_MINADBSIZE (1024*1024) /*%< 1 Megabyte */ 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_adblameinfo dns_adblameinfo_t; typedef ISC_LIST(dns_adbentry_t) dns_adbentrylist_t; typedef struct dns_adbfetch dns_adbfetch_t; typedef struct dns_adbfetch6 dns_adbfetch6_t; /*% dns adb structure */ struct dns_adb { unsigned int magic; isc_mutex_t lock; isc_mutex_t reflock; /*%< Covers irefcnt, erefcnt */ isc_mutex_t overmemlock; /*%< Covers overmem */ isc_mem_t *mctx; dns_view_t *view; isc_taskmgr_t *taskmgr; isc_task_t *task; isc_boolean_t overmem; 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 *limp; /*%< dns_adblameinfo_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 */ /*! * Bucketized locks and lists for names. * * XXXRTH Have a per-bucket structure that contains all of these? */ dns_adbnamelist_t names[NBUCKETS]; /*% See dns_adbnamelist_t */ isc_mutex_t namelocks[NBUCKETS]; /*% See dns_adbnamelist_t */ isc_boolean_t name_sd[NBUCKETS]; /*% See dns_adbnamelist_t */ 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]; /*%< shutting down */ 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. */ /*% dns_adbname structure */ 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; unsigned int fetch_err; unsigned int fetch6_err; dns_adbfindlist_t finds; /* for LRU-based management */ isc_stdtime_t last_used; ISC_LINK(dns_adbname_t) plink; }; /*% The adbfetch structure */ struct dns_adbfetch { unsigned int magic; dns_adbnamehook_t *namehook; dns_adbentry_t *entry; dns_fetch_t *fetch; dns_rdataset_t rdataset; }; /*% * 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; }; /*% * This is a small widget that holds qname-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_adblameinfo { unsigned int magic; dns_name_t qname; dns_rdatatype_t qtype; isc_stdtime_t lame_timer; ISC_LINK(dns_adblameinfo_t) plink; }; /*% * An address entry. It holds quite a bit of information about addresses, * including edns state (in "flags"), rtt, and of course the address of * the host. */ struct dns_adbentry { unsigned int magic; int lock_bucket; unsigned int refcnt; unsigned int flags; unsigned int srtt; isc_sockaddr_t sockaddr; isc_stdtime_t expires; /*%< * A nonzero 'expires' field indicates that the entry should * persist until that time. This allows entries found * using dns_adb_findaddrinfo() to persist for a limited time * even though they are not necessarily associated with a * name. */ ISC_LIST(dns_adblameinfo_t) lameinfo; 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_adblameinfo_t *new_adblameinfo(dns_adb_t *, dns_name_t *, dns_rdatatype_t); static inline void free_adblameinfo(dns_adb_t *, dns_adblameinfo_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 isc_boolean_t free_adbfind(dns_adb_t *, dns_adbfind_t **); static inline dns_adbaddrinfo_t *new_adbaddrinfo(dns_adb_t *, dns_adbentry_t *, in_port_t); static inline dns_adbfetch_t *new_adbfetch(dns_adb_t *); static inline void free_adbfetch(dns_adb_t *, dns_adbfetch_t **); static inline dns_adbname_t *find_name_and_lock(dns_adb_t *, dns_name_t *, 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 *, isc_boolean_t debug, isc_stdtime_t); static void print_dns_name(FILE *, dns_name_t *); static void print_namehook_list(FILE *, const char *legend, dns_adbnamehooklist_t *list, isc_boolean_t debug, isc_stdtime_t now); static void print_find_list(FILE *, dns_adbname_t *); static void print_fetch_list(FILE *, dns_adbname_t *); static inline isc_boolean_t dec_adb_irefcnt(dns_adb_t *); static inline void inc_adb_irefcnt(dns_adb_t *); static inline void inc_adb_erefcnt(dns_adb_t *); static inline void inc_entry_refcnt(dns_adb_t *, dns_adbentry_t *, isc_boolean_t); static inline isc_boolean_t 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 isc_boolean_t clean_namehooks(dns_adb_t *, dns_adbnamehooklist_t *, isc_boolean_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 isc_boolean_t 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(dns_adbname_t *, isc_boolean_t, dns_rdatatype_t); static inline void check_exit(dns_adb_t *); static void destroy(dns_adb_t *); static isc_boolean_t shutdown_names(dns_adb_t *); static isc_boolean_t shutdown_entries(dns_adb_t *); static inline void link_name(dns_adb_t *, int, dns_adbname_t *); static inline isc_boolean_t unlink_name(dns_adb_t *, dns_adbname_t *); static inline void link_entry(dns_adb_t *, int, dns_adbentry_t *); static inline isc_boolean_t unlink_entry(dns_adb_t *, dns_adbentry_t *); static isc_boolean_t kill_name(dns_adbname_t **, isc_eventtype_t, isc_boolean_t); static void water(void *, int); static void dump_entry(FILE *, dns_adbentry_t *, isc_boolean_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_STARTATZONE DNS_ADBFIND_STARTATZONE #define NAME_DEAD(n) (((n)->flags & NAME_IS_DEAD) != 0) #define NAME_NEEDSPOKE(n) (((n)->flags & NAME_NEEDS_POKE) != 0) #define NAME_GLUEOK(n) (((n)->flags & NAME_GLUE_OK) != 0) #define NAME_HINTOK(n) (((n)->flags & NAME_HINT_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 a 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 and AAAA types. In some cases, * however, it makes more sense to test for a particular class of fetches, * like V4 or V6 above. * Note: since we have removed the support of A6 in adb, FETCH_A and FETCH_AAAA * are now equal to FETCH_V4 and FETCH_V6, respectively. */ #define NAME_FETCH_A(n) ((n)->fetch_a != NULL) #define NAME_FETCH_AAAA(n) ((n)->fetch_aaaa != NULL) #define NAME_FETCH_V4(n) (NAME_FETCH_A(n)) #define NAME_FETCH_V6(n) (NAME_FETCH_AAAA(n)) #define NAME_FETCH(n) (NAME_FETCH_V4(n) || NAME_FETCH_V6(n)) /* * 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_STARTATZONE(fn) (((fn)->options & DNS_ADBFIND_STARTATZONE) \ != 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 STARTATZONE_MATCHES(nf, o) (((nf)->flags & NAME_STARTATZONE) == \ ((o) & DNS_ADBFIND_STARTATZONE)) #define ENTER_LEVEL ISC_LOG_DEBUG(50) #define EXIT_LEVEL ENTER_LEVEL #define CLEAN_LEVEL ISC_LOG_DEBUG(100) #define DEF_LEVEL ISC_LOG_DEBUG(5) #define NCACHE_LEVEL ISC_LOG_DEBUG(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) #define NXDOMAIN_RESULT(r) ((r) == DNS_R_NXDOMAIN || \ (r) == DNS_R_NCACHENXDOMAIN) #define NXRRSET_RESULT(r) ((r) == DNS_R_NCACHENXRRSET || \ (r) == DNS_R_NXRRSET || \ (r) == DNS_R_HINTNXRRSET) /* * Error state rankings. */ #define FIND_ERR_SUCCESS 0 /* highest rank */ #define FIND_ERR_CANCELED 1 #define FIND_ERR_FAILURE 2 #define FIND_ERR_NXDOMAIN 3 #define FIND_ERR_NXRRSET 4 #define FIND_ERR_UNEXPECTED 5 #define FIND_ERR_NOTFOUND 6 #define FIND_ERR_MAX 7 static const char *errnames[] = { "success", "canceled", "failure", "nxdomain", "nxrrset", "unexpected", "not_found" }; #define NEWERR(old, new) (ISC_MIN((old), (new))) static isc_result_t find_err_map[FIND_ERR_MAX] = { ISC_R_SUCCESS, ISC_R_CANCELED, ISC_R_FAILURE, DNS_R_NXDOMAIN, DNS_R_NXRRSET, ISC_R_UNEXPECTED, ISC_R_NOTFOUND /* not YET found */ }; static void DP(int level, const char *format, ...) ISC_FORMAT_PRINTF(2, 3); static void DP(int level, const char *format, ...) { va_list args; va_start(args, format); isc_log_vwrite(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_ADB, level, format, args); va_end(args); } /*% * Increment resolver-related statistics counters. */ static inline void inc_stats(dns_adb_t *adb, dns_statscounter_t counter) { if (adb->view->resstats != NULL) dns_generalstats_increment(adb->view->resstats, counter); } static inline dns_ttl_t ttlclamp(dns_ttl_t ttl) { if (ttl < ADB_CACHE_MINIMUM) ttl = ADB_CACHE_MINIMUM; if (ttl > ADB_CACHE_MAXIMUM) ttl = ADB_CACHE_MAXIMUM; return (ttl); } /* * 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_adbnamehook_t *anh; dns_rdata_t rdata = DNS_RDATA_INIT; 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; dns_adbnamehooklist_t *hookhead; 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_rdata_reset(&rdata); 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, 0); hookhead = &adbname->v4; } else { INSIST(rdata.length == 16); memcpy(in6a.s6_addr, rdata.data, 16); isc_sockaddr_fromin6(&sockaddr, &in6a, 0); hookhead = &adbname->v6; } 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 { for (anh = ISC_LIST_HEAD(*hookhead); anh != NULL; anh = ISC_LIST_NEXT(anh, plink)) if (anh->entry == foundentry) break; if (anh == NULL) { foundentry->refcnt++; nh->entry = foundentry; } else free_adbnamehook(adb, &nh); } new_addresses_added = ISC_TRUE; if (nh != NULL) ISC_LIST_APPEND(*hookhead, nh, plink); nh = NULL; result = dns_rdataset_next(rdataset); } fail: if (nh != NULL) free_adbnamehook(adb, &nh); if (addr_bucket != DNS_ADB_INVALIDBUCKET) UNLOCK(&adb->entrylocks[addr_bucket]); if (rdataset->trust == dns_trust_glue || rdataset->trust == dns_trust_additional) rdataset->ttl = ADB_CACHE_MINIMUM; else rdataset->ttl = ttlclamp(rdataset->ttl); 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); } /* * Requires the name's bucket be locked. */ static isc_boolean_t kill_name(dns_adbname_t **n, isc_eventtype_t ev, isc_boolean_t is_purge) { dns_adbname_t *name; isc_boolean_t result = ISC_FALSE; isc_boolean_t result4, result6; 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)) { result = unlink_name(adb, name); free_adbname(adb, &name); if (result) result = dec_adb_irefcnt(adb); return (result); } /* * 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); result4 = clean_namehooks(adb, &name->v4, is_purge); result6 = clean_namehooks(adb, &name->v6, is_purge); clean_target(adb, &name->target); result = ISC_TF(result4 || result6); /* * If fetches are running, cancel them. If none are running, we can * just kill the name here. */ if (!NAME_FETCH(name)) { INSIST(result == ISC_FALSE); result = unlink_name(adb, name); free_adbname(adb, &name); if (result) result = dec_adb_irefcnt(adb); } else { name->flags |= NAME_IS_DEAD; cancel_fetches_at_name(name); } return (result); } /* * Requires the name's bucket be locked and no entry buckets be locked. */ static isc_boolean_t check_expire_namehooks(dns_adbname_t *name, isc_stdtime_t now) { dns_adb_t *adb; isc_boolean_t result4 = ISC_FALSE; isc_boolean_t result6 = ISC_FALSE; 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); result4 = clean_namehooks(adb, &name->v4, ISC_FALSE); name->partial_result &= ~DNS_ADBFIND_INET; } name->expire_v4 = INT_MAX; name->fetch_err = FIND_ERR_UNEXPECTED; } /* * 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); result6 = clean_namehooks(adb, &name->v6, ISC_FALSE); name->partial_result &= ~DNS_ADBFIND_INET6; } name->expire_v6 = INT_MAX; name->fetch6_err = FIND_ERR_UNEXPECTED; } /* * 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; } return (ISC_TF(result4 || result6)); } /* * 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 isc_boolean_t unlink_name(dns_adb_t *adb, dns_adbname_t *name) { int bucket; isc_boolean_t result = ISC_FALSE; 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) result = ISC_TRUE; return (result); } /* * 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 isc_boolean_t unlink_entry(dns_adb_t *adb, dns_adbentry_t *entry) { int bucket; isc_boolean_t result = ISC_FALSE; 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) result = ISC_TRUE; return (result); } 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 isc_boolean_t shutdown_names(dns_adb_t *adb) { int bucket; isc_boolean_t result = ISC_FALSE; 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. */ INSIST(result == ISC_FALSE); result = 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); INSIST(result == ISC_FALSE); result = kill_name(&name, DNS_EVENT_ADBSHUTDOWN, ISC_FALSE); name = next_name; } } UNLOCK(&adb->namelocks[bucket]); } return (result); } /* * The ADB _MUST_ be locked before calling. Also, exit conditions must be * checked after calling this function. */ static isc_boolean_t shutdown_entries(dns_adb_t *adb) { int bucket; isc_boolean_t result = ISC_FALSE; 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. */ result = 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) { result = unlink_entry(adb, entry); free_adbentry(adb, &entry); if (result) result = dec_adb_irefcnt(adb); } entry = next_entry; } } UNLOCK(&adb->entrylocks[bucket]); } return (result); } /* * Name bucket must be locked */ static void cancel_fetches_at_name(dns_adbname_t *name) { if (NAME_FETCH_A(name)) dns_resolver_cancelfetch(name->fetch_a->fetch); if (NAME_FETCH_AAAA(name)) dns_resolver_cancelfetch(name->fetch_aaaa->fetch); } /* * Assumes the name bucket is locked. */ static isc_boolean_t clean_namehooks(dns_adb_t *adb, dns_adbnamehooklist_t *namehooks, isc_boolean_t is_purge) { dns_adbentry_t *entry; dns_adbnamehook_t *namehook; int addr_bucket; isc_boolean_t result = ISC_FALSE; 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]); } /* * If we are in an overmem situation, force expiration * so that # of names and # of entries are well * balanced. */ if (is_purge) entry->expires = 0; result = 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]); return (result); } 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; int order; dns_rdata_t rdata = DNS_RDATA_INIT; dns_fixedname_t fixed1, fixed2; dns_name_t *prefix, *new_target; REQUIRE(dns_name_countlabels(target) == 0); if (rdataset->type == dns_rdatatype_cname) { dns_rdata_cname_t 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); result = dns_rdata_tostruct(&rdata, &cname, NULL); if (result != ISC_R_SUCCESS) return (result); result = dns_name_dup(&cname.cname, adb->mctx, target); dns_rdata_freestruct(&cname); if (result != ISC_R_SUCCESS) return (result); } else { dns_rdata_dname_t dname; INSIST(rdataset->type == dns_rdatatype_dname); namereln = dns_name_fullcompare(name, fname, &order, &nlabels); 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); result = dns_rdata_tostruct(&rdata, &dname, NULL); if (result != ISC_R_SUCCESS) return (result); /* * Construct the new target name. */ dns_fixedname_init(&fixed1); prefix = dns_fixedname_name(&fixed1); dns_fixedname_init(&fixed2); new_target = dns_fixedname_name(&fixed2); dns_name_split(name, nlabels, prefix, NULL); result = dns_name_concatenate(prefix, &dname.dname, new_target, NULL); dns_rdata_freestruct(&dname); 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->ev_destroy_arg; INSIST(DNS_ADBFIND_VALID(find)); LOCK(&find->lock); find->flags |= FIND_EVENT_FREED; event->ev_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, notify; 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; notify = wanted & addrs; switch (evtype) { case DNS_EVENT_ADBMOREADDRESSES: DP(ISC_LOG_DEBUG(3), "DNS_EVENT_ADBMOREADDRESSES"); if ((notify) != 0) { find->flags &= ~addrs; process = ISC_TRUE; } break; case DNS_EVENT_ADBNOMOREADDRESSES: DP(ISC_LOG_DEBUG(3), "DNS_EVENT_ADBNOMOREADDRESSES"); find->flags &= ~addrs; wanted = find->flags & DNS_ADBFIND_ADDRESSMASK; if (wanted == 0) process = ISC_TRUE; 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->ev_sender; ev->ev_sender = find; find->result_v4 = find_err_map[name->fetch_err]; find->result_v6 = find_err_map[name->fetch6_err]; ev->ev_type = evtype; ev->ev_destroy = event_free; ev->ev_destroy_arg = find; DP(DEF_LEVEL, "sending event %p to task %p for find %p", ev, task, find); isc_task_sendanddetach(&task, (isc_event_t **)&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; /* * The caller must be holding the adb lock. */ if (adb->shutting_down) { /* * If there aren't any external references either, we're * done. Send the control event to initiate shutdown. */ INSIST(!adb->cevent_sent); /* Sanity check. */ event = &adb->cevent; isc_task_send(adb->task, &event); adb->cevent_sent = ISC_TRUE; } } static inline isc_boolean_t dec_adb_irefcnt(dns_adb_t *adb) { isc_event_t *event; isc_task_t *etask; isc_boolean_t result = ISC_FALSE; LOCK(&adb->reflock); INSIST(adb->irefcnt > 0); adb->irefcnt--; if (adb->irefcnt == 0) { event = ISC_LIST_HEAD(adb->whenshutdown); while (event != NULL) { ISC_LIST_UNLINK(adb->whenshutdown, event, ev_link); etask = event->ev_sender; event->ev_sender = adb; isc_task_sendanddetach(&etask, &event); event = ISC_LIST_HEAD(adb->whenshutdown); } } if (adb->irefcnt == 0 && adb->erefcnt == 0) result = ISC_TRUE; UNLOCK(&adb->reflock); return (result); } static inline void inc_adb_irefcnt(dns_adb_t *adb) { LOCK(&adb->reflock); adb->irefcnt++; UNLOCK(&adb->reflock); } static inline void inc_adb_erefcnt(dns_adb_t *adb) { LOCK(&adb->reflock); adb->erefcnt++; UNLOCK(&adb->reflock); } 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 isc_boolean_t dec_entry_refcnt(dns_adb_t *adb, dns_adbentry_t *entry, isc_boolean_t lock) { int bucket; isc_boolean_t destroy_entry; isc_boolean_t result = ISC_FALSE; 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; result = unlink_entry(adb, entry); } if (lock) UNLOCK(&adb->entrylocks[bucket]); if (!destroy_entry) return (result); entry->lock_bucket = DNS_ADB_INVALIDBUCKET; free_adbentry(adb, &entry); if (result) result = dec_adb_irefcnt(adb); return (result); } 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; name->fetch_err = FIND_ERR_UNEXPECTED; name->fetch6_err = FIND_ERR_UNEXPECTED; 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_adblameinfo_t * new_adblameinfo(dns_adb_t *adb, dns_name_t *qname, dns_rdatatype_t qtype) { dns_adblameinfo_t *li; li = isc_mempool_get(adb->limp); if (li == NULL) return (NULL); dns_name_init(&li->qname, NULL); if (dns_name_dup(qname, adb->mctx, &li->qname) != ISC_R_SUCCESS) { isc_mempool_put(adb->limp, li); return (NULL); } li->magic = DNS_ADBLAMEINFO_MAGIC; li->lame_timer = 0; li->qtype = qtype; ISC_LINK_INIT(li, plink); return (li); } static inline void free_adblameinfo(dns_adb_t *adb, dns_adblameinfo_t **lameinfo) { dns_adblameinfo_t *li; INSIST(lameinfo != NULL && DNS_ADBLAMEINFO_VALID(*lameinfo)); li = *lameinfo; *lameinfo = NULL; INSIST(!ISC_LINK_LINKED(li, plink)); dns_name_free(&li->qname, adb->mctx); li->magic = 0; isc_mempool_put(adb->limp, li); } 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; isc_random_get(&r); e->srtt = (r & 0x1f) + 1; e->expires = 0; ISC_LIST_INIT(e->lameinfo); 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_adblameinfo_t *li; 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; li = ISC_LIST_HEAD(e->lameinfo); while (li != NULL) { ISC_LIST_UNLINK(e->lameinfo, li, plink); free_adblameinfo(adb, &li); li = ISC_LIST_HEAD(e->lameinfo); } 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; h->result_v4 = ISC_R_UNEXPECTED; h->result_v6 = ISC_R_UNEXPECTED; 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) { 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); inc_adb_irefcnt(adb); 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); } static inline isc_boolean_t 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; DESTROYLOCK(&find->lock); isc_mempool_put(adb->ahmp, find); return (dec_adb_irefcnt(adb)); } /* * 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, in_port_t port) { dns_adbaddrinfo_t *ai; ai = isc_mempool_get(adb->aimp); if (ai == NULL) return (NULL); ai->magic = DNS_ADBADDRINFO_MAGIC; ai->sockaddr = entry->sockaddr; isc_sockaddr_setport(&ai->sockaddr, port); 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->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_fullhash(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) && STARTATZONE_MATCHES(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_lame(dns_adb_t *adb, dns_adbentry_t *entry, dns_name_t *qname, dns_rdatatype_t qtype, isc_stdtime_t now) { dns_adblameinfo_t *li, *next_li; isc_boolean_t is_bad; is_bad = ISC_FALSE; li = ISC_LIST_HEAD(entry->lameinfo); if (li == NULL) return (ISC_FALSE); while (li != NULL) { next_li = ISC_LIST_NEXT(li, plink); /* * Has the entry expired? */ if (li->lame_timer < now) { ISC_LIST_UNLINK(entry->lameinfo, li, plink); free_adblameinfo(adb, &li); } /* * Order tests from least to most expensive. * * We do not break out of the main loop here as * we use the loop for house keeping. */ if (li != NULL && !is_bad && li->qtype == qtype && dns_name_equal(qname, &li->qname)) is_bad = ISC_TRUE; li = next_li; } return (is_bad); } static void copy_namehook_lists(dns_adb_t *adb, dns_adbfind_t *find, dns_name_t *qname, dns_rdatatype_t qtype, dns_adbname_t *name, isc_stdtime_t now) { dns_adbnamehook_t *namehook; dns_adbaddrinfo_t *addrinfo; dns_adbentry_t *entry; int bucket; bucket = DNS_ADB_INVALIDBUCKET; if (find->options & DNS_ADBFIND_INET) { namehook = ISC_LIST_HEAD(name->v4); while (namehook != NULL) { entry = namehook->entry; bucket = entry->lock_bucket; LOCK(&adb->entrylocks[bucket]); if (!FIND_RETURNLAME(find) && entry_is_lame(adb, entry, qname, qtype, now)) { find->options |= DNS_ADBFIND_LAMEPRUNED; goto nextv4; } addrinfo = new_adbaddrinfo(adb, entry, find->port); 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, 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) { entry = namehook->entry; bucket = entry->lock_bucket; LOCK(&adb->entrylocks[bucket]); if (!FIND_RETURNLAME(find) && entry_is_lame(adb, entry, qname, qtype, now)) { find->options |= DNS_ADBFIND_LAMEPRUNED; goto nextv6; } addrinfo = new_adbaddrinfo(adb, entry, find->port); 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, 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; UNUSED(task); adb = ev->ev_arg; INSIST(DNS_ADB_VALID(adb)); isc_event_free(&ev); /* * Wait for lock around check_exit() call to be released. */ LOCK(&adb->lock); UNLOCK(&adb->lock); destroy(adb); } /* * Name bucket must be locked; adb may be locked; no other locks held. */ static isc_boolean_t check_expire_name(dns_adbname_t **namep, isc_stdtime_t now) { dns_adbname_t *name; isc_boolean_t result = ISC_FALSE; INSIST(namep != NULL && DNS_ADBNAME_VALID(*namep)); name = *namep; if (NAME_HAS_V4(name) || NAME_HAS_V6(name)) return (result); if (NAME_FETCH(name)) return (result); if (!EXPIRE_OK(name->expire_v4, now)) return (result); if (!EXPIRE_OK(name->expire_v6, now)) return (result); if (!EXPIRE_OK(name->expire_target, now)) return (result); /* * The name is empty. Delete it. */ result = kill_name(&name, DNS_EVENT_ADBEXPIRED, ISC_FALSE); *namep = NULL; /* * Our caller, or one of its callers, will be calling check_exit() at * some point, so we don't need to do it here. */ return (result); } /*% * Examine the tail entry of the LRU list to see if it expires or is stale * (unused for some period); if so, the name entry will be freed. If the ADB * is in the overmem condition, the tail and the next to tail entries * will be unconditionally removed (unless they have an outstanding fetch). * We don't care about a race on 'overmem' at the risk of causing some * collateral damage or a small delay in starting cleanup, so we don't bother * to lock ADB (if it's not locked). * * Name bucket must be locked; adb may be locked; no other locks held. */ static void check_stale_name(dns_adb_t *adb, int bucket, isc_stdtime_t now) { int victims, max_victims; isc_boolean_t result; dns_adbname_t *victim, *next_victim; isc_boolean_t overmem = adb->overmem; int scans = 0; INSIST(bucket != DNS_ADB_INVALIDBUCKET); max_victims = overmem ? 2 : 1; /* * We limit the number of scanned entries to 10 (arbitrary choice) * in order to avoid examining too many entries when there are many * tail entries that have fetches (this should be rare, but could * happen). */ victim = ISC_LIST_TAIL(adb->names[bucket]); for (victims = 0; victim != NULL && victims < max_victims && scans < 10; victim = next_victim) { scans++; next_victim = ISC_LIST_PREV(victim, plink); /* * If the victim is already dead, it simply waits for some * final events. Ignore it. */ if (NAME_DEAD(victim)) goto next; result = check_expire_name(&victim, now); if (victim == NULL) { victims++; goto next; } if (!NAME_FETCH(victim) && (overmem || victim->last_used + ADB_STALE_MARGIN <= now)) { RUNTIME_CHECK(kill_name(&victim, DNS_EVENT_ADBCANCELED, ISC_TRUE) == ISC_FALSE); victims++; } next: if (!overmem) break; } } /* * Entry bucket must be locked; adb may be locked; no other locks held. */ static isc_boolean_t check_expire_entry(dns_adb_t *adb, dns_adbentry_t **entryp, isc_stdtime_t now) { dns_adbentry_t *entry; isc_boolean_t result = ISC_FALSE; INSIST(entryp != NULL && DNS_ADBENTRY_VALID(*entryp)); entry = *entryp; if (entry->refcnt != 0) return (result); if (entry->expires == 0 || entry->expires > now) return (result); /* * The entry is not in use. Delete it. */ DP(DEF_LEVEL, "killing entry %p", entry); INSIST(ISC_LINK_LINKED(entry, plink)); result = unlink_entry(adb, entry); free_adbentry(adb, &entry); if (result) dec_adb_irefcnt(adb); *entryp = NULL; return (result); } /* * ADB must be locked, and no other locks held. */ static isc_boolean_t cleanup_names(dns_adb_t *adb, int bucket, isc_stdtime_t now) { dns_adbname_t *name; dns_adbname_t *next_name; isc_boolean_t result = ISC_FALSE; DP(CLEAN_LEVEL, "cleaning name bucket %d", bucket); LOCK(&adb->namelocks[bucket]); if (adb->name_sd[bucket]) { UNLOCK(&adb->namelocks[bucket]); return (result); } name = ISC_LIST_HEAD(adb->names[bucket]); while (name != NULL) { next_name = ISC_LIST_NEXT(name, plink); INSIST(result == ISC_FALSE); result = check_expire_namehooks(name, now); if (!result) result = check_expire_name(&name, now); name = next_name; } UNLOCK(&adb->namelocks[bucket]); return (result); } /* * ADB must be locked, and no other locks held. */ static isc_boolean_t cleanup_entries(dns_adb_t *adb, int bucket, isc_stdtime_t now) { dns_adbentry_t *entry, *next_entry; isc_boolean_t result = ISC_FALSE; 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); INSIST(result == ISC_FALSE); result = check_expire_entry(adb, &entry, now); entry = next_entry; } UNLOCK(&adb->entrylocks[bucket]); return (result); } static void destroy(dns_adb_t *adb) { adb->magic = 0; isc_task_detach(&adb->task); isc_mempool_destroy(&adb->nmp); isc_mempool_destroy(&adb->nhmp); isc_mempool_destroy(&adb->limp); isc_mempool_destroy(&adb->emp); isc_mempool_destroy(&adb->ahmp); isc_mempool_destroy(&adb->aimp); isc_mempool_destroy(&adb->afmp); DESTROYMUTEXBLOCK(adb->entrylocks, NBUCKETS); DESTROYMUTEXBLOCK(adb->namelocks, NBUCKETS); DESTROYLOCK(&adb->reflock); DESTROYLOCK(&adb->lock); DESTROYLOCK(&adb->mplock); DESTROYLOCK(&adb->overmemlock); isc_mem_putanddetach(&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); /* this is actually unused */ REQUIRE(taskmgr != NULL); REQUIRE(newadb != NULL && *newadb == NULL); UNUSED(timermgr); 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->limp = NULL; adb->emp = NULL; adb->ahmp = NULL; adb->aimp = NULL; adb->afmp = NULL; adb->task = NULL; adb->mctx = NULL; adb->view = view; 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; adb->overmem = ISC_FALSE; ISC_LIST_INIT(adb->whenshutdown); isc_mem_attach(mem, &adb->mctx); 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->reflock); if (result != ISC_R_SUCCESS) goto fail0d; result = isc_mutex_init(&adb->overmemlock); if (result != ISC_R_SUCCESS) goto fail0e; /* * 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, 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); \ isc_mempool_associatelock((p), &adb->mplock); \ } while (0) MPINIT(dns_adbname_t, adb->nmp, "adbname"); MPINIT(dns_adbnamehook_t, adb->nhmp, "adbnamehook"); MPINIT(dns_adblameinfo_t, adb->limp, "adblameinfo"); MPINIT(dns_adbentry_t, adb->emp, "adbentry"); MPINIT(dns_adbfind_t, adb->ahmp, "adbfind"); MPINIT(dns_adbaddrinfo_t, adb->aimp, "adbaddrinfo"); MPINIT(dns_adbfetch_t, adb->afmp, "adbfetch"); #undef MPINIT /* * Allocate an internal task. */ result = isc_task_create(adb->taskmgr, 0, &adb->task); if (result != ISC_R_SUCCESS) goto fail3; isc_task_setname(adb->task, "ADB", adb); /* * Normal return. */ adb->magic = DNS_ADB_MAGIC; *newadb = adb; return (ISC_R_SUCCESS); fail3: if (adb->task != NULL) isc_task_detach(&adb->task); /* clean up entrylocks */ DESTROYMUTEXBLOCK(adb->entrylocks, NBUCKETS); fail2: /* clean up namelocks */ DESTROYMUTEXBLOCK(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->limp != NULL) isc_mempool_destroy(&adb->limp); 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); DESTROYLOCK(&adb->overmemlock); fail0e: DESTROYLOCK(&adb->reflock); fail0d: DESTROYLOCK(&adb->mplock); fail0c: DESTROYLOCK(&adb->lock); fail0b: isc_mem_putanddetach(&adb->mctx, adb, sizeof(dns_adb_t)); return (result); } void dns_adb_attach(dns_adb_t *adb, dns_adb_t **adbx) { REQUIRE(DNS_ADB_VALID(adb)); REQUIRE(adbx != NULL && *adbx == NULL); inc_adb_erefcnt(adb); *adbx = adb; } void dns_adb_detach(dns_adb_t **adbx) { dns_adb_t *adb; isc_boolean_t need_exit_check; REQUIRE(adbx != NULL && DNS_ADB_VALID(*adbx)); adb = *adbx; *adbx = NULL; INSIST(adb->erefcnt > 0); LOCK(&adb->reflock); adb->erefcnt--; need_exit_check = ISC_TF(adb->erefcnt == 0 && adb->irefcnt == 0); UNLOCK(&adb->reflock); if (need_exit_check) { LOCK(&adb->lock); INSIST(adb->shutting_down); check_exit(adb); 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->reflock); zeroirefcnt = ISC_TF(adb->irefcnt == 0); if (adb->shutting_down && zeroirefcnt && isc_mempool_getallocated(adb->ahmp) == 0) { /* * We're already shutdown. Send the event. */ event->ev_sender = adb; isc_task_send(task, &event); } else { clone = NULL; isc_task_attach(task, &clone); event->ev_sender = clone; ISC_LIST_APPEND(adb->whenshutdown, event, ev_link); } UNLOCK(&adb->reflock); UNLOCK(&adb->lock); } void dns_adb_shutdown(dns_adb_t *adb) { isc_boolean_t need_check_exit; /* * Shutdown 'adb'. */ LOCK(&adb->lock); if (!adb->shutting_down) { adb->shutting_down = ISC_TRUE; isc_mem_setwater(adb->mctx, water, adb, 0, 0); need_check_exit = shutdown_names(adb); if (!need_check_exit) need_check_exit = shutdown_entries(adb); if (need_check_exit) 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 *qname, dns_rdatatype_t qtype, unsigned int options, isc_stdtime_t now, dns_name_t *target, in_port_t port, dns_adbfind_t **findp) { dns_adbfind_t *find; dns_adbname_t *adbname; int bucket; isc_boolean_t want_event, start_at_zone, alias, have_address; 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(qname != 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_zone = 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); find->port = port; /* * 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"); RUNTIME_CHECK(free_adbfind(adb, &find) == ISC_FALSE); result = ISC_R_SHUTTINGDOWN; goto out; } /* * Nothing found. Allocate a new adbname structure for this name. */ if (adbname == NULL) { /* * See if there is any stale name at the end of list, and purge * it if so. */ check_stale_name(adb, bucket, now); adbname = new_adbname(adb, name); if (adbname == NULL) { RUNTIME_CHECK(free_adbfind(adb, &find) == ISC_FALSE); 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; if (FIND_STARTATZONE(find)) adbname->flags |= NAME_STARTATZONE; } else { /* Move this name forward in the LRU list */ ISC_LIST_UNLINK(adb->names[bucket], adbname, plink); ISC_LIST_PREPEND(adb->names[bucket], adbname, plink); } adbname->last_used = now; /* * Expire old entries, etc. */ RUNTIME_CHECK(check_expire_namehooks(adbname, now) == ISC_FALSE); /* * 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. First try looking for an A record * in the database. */ if (!NAME_HAS_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; } /* * If the name doesn't exist at all, don't bother with * v6 queries; they won't work. * * If the name does exist but we didn't get our data, go * ahead and try AAAA. * * If the result is neither of these, try a fetch for A. */ if (NXDOMAIN_RESULT(result)) goto fetch; else if (NXRRSET_RESULT(result)) goto v6; if (!NAME_FETCH_V4(adbname)) wanted_fetches |= DNS_ADBFIND_INET; } v6: if (!NAME_HAS_V6(adbname) && EXPIRE_OK(adbname->expire_v6, now) && WANT_INET6(wanted_addresses)) { result = dbfind_name(adbname, now, dns_rdatatype_aaaa); if (result == ISC_R_SUCCESS) { DP(DEF_LEVEL, "dns_adb_createfind: found AAAA 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; if (!NAME_FETCH_V6(adbname)) wanted_fetches |= DNS_ADBFIND_INET6; } fetch: if ((WANT_INET(wanted_addresses) && NAME_HAS_V4(adbname)) || (WANT_INET6(wanted_addresses) && NAME_HAS_V6(adbname))) have_address = ISC_TRUE; else have_address = ISC_FALSE; if (wanted_fetches != 0 && ! (FIND_AVOIDFETCHES(find) && have_address)) { /* * 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_STARTATZONE(find)) start_at_zone = ISC_TRUE; /* * Start V4. */ if (WANT_INET(wanted_fetches) && fetch_name(adbname, start_at_zone, dns_rdatatype_a) == 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(adbname, start_at_zone, dns_rdatatype_aaaa) == ISC_R_SUCCESS) { DP(DEF_LEVEL, "dns_adb_createfind: " "started AAAA fetch for name %p", adbname); } } /* * Run through the name and copy out the bits we are * interested in. */ copy_namehook_lists(adb, find, qname, qtype, 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_copy(&adbname->target, target, NULL); if (result != ISC_R_SUCCESS) goto out; } result = DNS_R_ALIAS; } else result = ISC_R_SUCCESS; /* * Copy out error flags from the name structure into the find. */ find->result_v4 = find_err_map[adbname->fetch_err]; find->result_v6 = find_err_map[adbname->fetch6_err]; 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.ev_sender = taskp; find->event.ev_action = action; find->event.ev_arg = arg; } } 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; INSIST(DNS_ADBENTRY_VALID(entry)); RUNTIME_CHECK(dec_entry_refcnt(adb, entry, ISC_TRUE) == ISC_FALSE); 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); if (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->ev_sender; ev->ev_sender = find; ev->ev_type = DNS_EVENT_ADBCANCELED; ev->ev_destroy = event_free; ev->ev_destroy_arg = find; find->result_v4 = ISC_R_CANCELED; find->result_v6 = ISC_R_CANCELED; DP(DEF_LEVEL, "sending event %p to task %p for find %p", ev, task, find); isc_task_sendanddetach(&task, (isc_event_t **)&ev); } UNLOCK(&find->lock); } void dns_adb_dump(dns_adb_t *adb, FILE *f) { int i; isc_stdtime_t now; 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 leisure. */ LOCK(&adb->lock); isc_stdtime_get(&now); for (i = 0; i < NBUCKETS; i++) RUNTIME_CHECK(cleanup_names(adb, i, now) == ISC_FALSE); for (i = 0; i < NBUCKETS; i++) RUNTIME_CHECK(cleanup_entries(adb, i, now) == ISC_FALSE); dump_adb(adb, f, ISC_FALSE, now); UNLOCK(&adb->lock); } static void dump_ttl(FILE *f, const char *legend, isc_stdtime_t value, isc_stdtime_t now) { if (value == INT_MAX) return; fprintf(f, " [%s TTL %d]", legend, value - now); } static void dump_adb(dns_adb_t *adb, FILE *f, isc_boolean_t debug, isc_stdtime_t now) { int i; dns_adbname_t *name; dns_adbentry_t *entry; fprintf(f, ";\n; Address database dump\n;\n"); if (debug) fprintf(f, "; addr %p, erefcnt %u, irefcnt %u, finds out %u\n", adb, 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 */ for (i = 0; i < NBUCKETS; i++) { name = ISC_LIST_HEAD(adb->names[i]); if (name == NULL) continue; if (debug) fprintf(f, "; bucket %d\n", i); for (; name != NULL; name = ISC_LIST_NEXT(name, plink)) { if (debug) fprintf(f, "; name %p (flags %08x)\n", name, name->flags); fprintf(f, "; "); print_dns_name(f, &name->name); if (dns_name_countlabels(&name->target) > 0) { fprintf(f, " alias "); print_dns_name(f, &name->target); } dump_ttl(f, "v4", name->expire_v4, now); dump_ttl(f, "v6", name->expire_v6, now); dump_ttl(f, "target", name->expire_target, now); fprintf(f, " [v4 %s] [v6 %s]", errnames[name->fetch_err], errnames[name->fetch6_err]); fprintf(f, "\n"); print_namehook_list(f, "v4", &name->v4, debug, now); print_namehook_list(f, "v6", &name->v6, debug, now); if (debug) print_fetch_list(f, name); if (debug) print_find_list(f, name); } } fprintf(f, ";\n; Unassociated entries\n;\n"); for (i = 0; i < NBUCKETS; i++) { entry = ISC_LIST_HEAD(adb->entries[i]); while (entry != NULL) { if (entry->refcnt == 0) dump_entry(f, entry, debug, now); 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]); } static void dump_entry(FILE *f, dns_adbentry_t *entry, isc_boolean_t debug, isc_stdtime_t now) { char addrbuf[ISC_NETADDR_FORMATSIZE]; char typebuf[DNS_RDATATYPE_FORMATSIZE]; isc_netaddr_t netaddr; dns_adblameinfo_t *li; isc_netaddr_fromsockaddr(&netaddr, &entry->sockaddr); isc_netaddr_format(&netaddr, addrbuf, sizeof(addrbuf)); if (debug) fprintf(f, ";\t%p: refcnt %u\n", entry, entry->refcnt); fprintf(f, ";\t%s [srtt %u] [flags %08x]", addrbuf, entry->srtt, entry->flags); if (entry->expires != 0) fprintf(f, " [ttl %d]", entry->expires - now); fprintf(f, "\n"); for (li = ISC_LIST_HEAD(entry->lameinfo); li != NULL; li = ISC_LIST_NEXT(li, plink)) { fprintf(f, ";\t\t"); print_dns_name(f, &li->qname); dns_rdatatype_format(li->qtype, typebuf, sizeof(typebuf)); fprintf(f, " %s [lame TTL %d]\n", typebuf, li->lame_timer - now); } } 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.ev_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 = "BadAddress"; fprintf(f, "\t\tentry %p, flags %08x" " srtt %u addr %s\n", ai->entry, ai->flags, 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[DNS_NAME_FORMATSIZE]; INSIST(f != NULL); dns_name_format(name, buf, sizeof(buf)); fprintf(f, "%s", buf); } static void print_namehook_list(FILE *f, const char *legend, dns_adbnamehooklist_t *list, isc_boolean_t debug, isc_stdtime_t now) { dns_adbnamehook_t *nh; for (nh = ISC_LIST_HEAD(*list); nh != NULL; nh = ISC_LIST_NEXT(nh, plink)) { if (debug) fprintf(f, ";\tHook(%s) %p\n", legend, nh); dump_entry(f, nh->entry, debug, now); } } static inline void print_fetch(FILE *f, dns_adbfetch_t *ft, const char *type) { fprintf(f, "\t\tFetch(%s): %p -> { nh %p, entry %p, fetch %p }\n", type, ft, ft->namehook, ft->entry, ft->fetch); } static void print_fetch_list(FILE *f, dns_adbname_t *n) { if (NAME_FETCH_A(n)) print_fetch(f, n->fetch_a, "A"); if (NAME_FETCH_AAAA(n)) print_fetch(f, n->fetch_aaaa, "AAAA"); } 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); if (rdtype == dns_rdatatype_a) adbname->fetch_err = FIND_ERR_UNEXPECTED; else adbname->fetch6_err = FIND_ERR_UNEXPECTED; result = dns_view_find(adb->view, &adbname->name, rdtype, now, NAME_GLUEOK(adbname) ? DNS_DBFIND_GLUEOK : 0, ISC_TF(NAME_HINTOK(adbname)), NULL, NULL, fname, &rdataset, NULL); /* XXXVIX this switch statement is too sparse to gen a jump table. */ switch (result) { case DNS_R_GLUE: case DNS_R_HINT: case ISC_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. */ if (rdtype == dns_rdatatype_a) adbname->fetch_err = FIND_ERR_SUCCESS; else adbname->fetch6_err = FIND_ERR_SUCCESS; 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); if (result == DNS_R_NXDOMAIN) adbname->fetch_err = FIND_ERR_NXDOMAIN; else adbname->fetch_err = FIND_ERR_NXRRSET; } else { DP(NCACHE_LEVEL, "adb name %p: Caching auth negative entry for AAAA", adbname); adbname->expire_v6 = now + 30; if (result == DNS_R_NXDOMAIN) adbname->fetch6_err = FIND_ERR_NXDOMAIN; else adbname->fetch6_err = FIND_ERR_NXRRSET; } 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 = ttlclamp(rdataset.ttl); if (rdtype == dns_rdatatype_a) { adbname->expire_v4 = rdataset.ttl + now; if (result == DNS_R_NCACHENXDOMAIN) adbname->fetch_err = FIND_ERR_NXDOMAIN; else adbname->fetch_err = FIND_ERR_NXRRSET; 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; if (result == DNS_R_NCACHENXDOMAIN) adbname->fetch6_err = FIND_ERR_NXDOMAIN; else adbname->fetch6_err = FIND_ERR_NXRRSET; } 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 = ttlclamp(rdataset.ttl); 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; } if (rdtype == dns_rdatatype_a) adbname->fetch_err = FIND_ERR_SUCCESS; else adbname->fetch6_err = FIND_ERR_SUCCESS; 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; UNUSED(task); INSIST(ev->ev_type == DNS_EVENT_FETCHDONE); dev = (dns_fetchevent_t *)ev; name = ev->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; } else fetch = NULL; INSIST(address_type != 0 && fetch != NULL); 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); want_check_exit = kill_name(&name, DNS_EVENT_ADBCANCELED, ISC_FALSE); 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 = ttlclamp(dev->rdataset->ttl); 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); if (dev->result == DNS_R_NCACHENXDOMAIN) name->fetch_err = FIND_ERR_NXDOMAIN; else name->fetch_err = FIND_ERR_NXRRSET; inc_stats(adb, dns_resstatscounter_gluefetchv4fail); } 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); if (dev->result == DNS_R_NCACHENXDOMAIN) name->fetch6_err = FIND_ERR_NXDOMAIN; else name->fetch6_err = FIND_ERR_NXRRSET; inc_stats(adb, dns_resstatscounter_gluefetchv6fail); } goto out; } /* * Handle CNAME/DNAME. */ if (dev->result == DNS_R_CNAME || dev->result == DNS_R_DNAME) { dev->rdataset->ttl = ttlclamp(dev->rdataset->ttl); 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) { char buf[DNS_NAME_FORMATSIZE]; dns_name_format(&name->name, buf, sizeof(buf)); DP(DEF_LEVEL, "adb: fetch of '%s' %s failed: %s", buf, address_type == DNS_ADBFIND_INET ? "A" : "AAAA", dns_result_totext(dev->result)); /* XXXMLG Don't pound on bad servers. */ if (address_type == DNS_ADBFIND_INET) { name->expire_v4 = ISC_MIN(name->expire_v4, now + 300); name->fetch_err = FIND_ERR_FAILURE; inc_stats(adb, dns_resstatscounter_gluefetchv4fail); } else { name->expire_v6 = ISC_MIN(name->expire_v6, now + 300); name->fetch6_err = FIND_ERR_FAILURE; inc_stats(adb, dns_resstatscounter_gluefetchv6fail); } 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; if (address_type == DNS_ADBFIND_INET) name->fetch_err = FIND_ERR_SUCCESS; else name->fetch6_err = FIND_ERR_SUCCESS; } out: free_adbfetch(adb, &fetch); isc_event_free(&ev); clean_finds_at_name(name, ev_status, address_type); UNLOCK(&adb->namelocks[bucket]); } static isc_result_t fetch_name(dns_adbname_t *adbname, isc_boolean_t start_at_zone, dns_rdatatype_t type) { isc_result_t result; dns_adbfetch_t *fetch = NULL; dns_adb_t *adb; dns_fixedname_t fixed; dns_name_t *name; dns_rdataset_t rdataset; dns_rdataset_t *nameservers; unsigned int options; INSIST(DNS_ADBNAME_VALID(adbname)); adb = adbname->adb; INSIST(DNS_ADB_VALID(adb)); INSIST((type == dns_rdatatype_a && !NAME_FETCH_V4(adbname)) || (type == dns_rdatatype_aaaa && !NAME_FETCH_V6(adbname))); adbname->fetch_err = FIND_ERR_NOTFOUND; name = NULL; nameservers = NULL; dns_rdataset_init(&rdataset); options = DNS_FETCHOPT_NOVALIDATE; if (start_at_zone) { DP(ENTER_LEVEL, "fetch_name: starting at zone for name %p", adbname); dns_fixedname_init(&fixed); name = dns_fixedname_name(&fixed); result = dns_view_findzonecut2(adb->view, &adbname->name, name, 0, 0, ISC_TRUE, ISC_FALSE, &rdataset, NULL); if (result != ISC_R_SUCCESS && result != DNS_R_HINT) goto cleanup; nameservers = &rdataset; options |= DNS_FETCHOPT_UNSHARED; } fetch = new_adbfetch(adb); if (fetch == NULL) { result = ISC_R_NOMEMORY; goto cleanup; } result = dns_resolver_createfetch(adb->view->resolver, &adbname->name, type, name, nameservers, NULL, options, adb->task, fetch_callback, adbname, &fetch->rdataset, NULL, &fetch->fetch); if (result != ISC_R_SUCCESS) goto cleanup; if (type == dns_rdatatype_a) { adbname->fetch_a = fetch; inc_stats(adb, dns_resstatscounter_gluefetchv4); } else { adbname->fetch_aaaa = fetch; inc_stats(adb, dns_resstatscounter_gluefetchv6); } fetch = NULL; /* Keep us from cleaning this up below. */ cleanup: if (fetch != NULL) free_adbfetch(adb, &fetch); if (dns_rdataset_isassociated(&rdataset)) dns_rdataset_disassociate(&rdataset); 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 *qname, dns_rdatatype_t qtype, isc_stdtime_t expire_time) { dns_adblameinfo_t *li; int bucket; isc_result_t result = ISC_R_SUCCESS; REQUIRE(DNS_ADB_VALID(adb)); REQUIRE(DNS_ADBADDRINFO_VALID(addr)); REQUIRE(qname != NULL); bucket = addr->entry->lock_bucket; LOCK(&adb->entrylocks[bucket]); li = ISC_LIST_HEAD(addr->entry->lameinfo); while (li != NULL && (li->qtype != qtype || !dns_name_equal(qname, &li->qname))) li = ISC_LIST_NEXT(li, plink); if (li != NULL) { if (expire_time > li->lame_timer) li->lame_timer = expire_time; goto unlock; } li = new_adblameinfo(adb, qname, qtype); if (li == NULL) { result = ISC_R_NOMEMORY; goto unlock; } li->lame_timer = expire_time; ISC_LIST_PREPEND(addr->entry->lameinfo, li, plink); unlock: UNLOCK(&adb->entrylocks[bucket]); return (result); } void dns_adb_adjustsrtt(dns_adb_t *adb, dns_adbaddrinfo_t *addr, unsigned int rtt, unsigned int factor) { int bucket; unsigned int new_srtt; isc_stdtime_t now; REQUIRE(DNS_ADB_VALID(adb)); REQUIRE(DNS_ADBADDRINFO_VALID(addr)); REQUIRE(factor <= 10); bucket = addr->entry->lock_bucket; LOCK(&adb->entrylocks[bucket]); if (factor == DNS_ADB_RTTADJAGE) new_srtt = addr->entry->srtt * 98 / 100; else new_srtt = (addr->entry->srtt / 10 * factor) + (rtt / 10 * (10 - factor)); addr->entry->srtt = new_srtt; addr->srtt = new_srtt; isc_stdtime_get(&now); addr->entry->expires = now + ADB_ENTRY_WINDOW; 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. */ 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, isc_stdtime_t now) { int bucket; dns_adbentry_t *entry; dns_adbaddrinfo_t *addr; isc_result_t result; in_port_t port; REQUIRE(DNS_ADB_VALID(adb)); REQUIRE(addrp != NULL && *addrp == NULL); UNUSED(now); 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(ENTER_LEVEL, "findaddrinfo: new entry %p", entry); } else DP(ENTER_LEVEL, "findaddrinfo: found entry %p", entry); port = isc_sockaddr_getport(sa); addr = new_adbaddrinfo(adb, entry, port); if (addr == NULL) { result = ISC_R_NOMEMORY; } else { 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 + ADB_ENTRY_WINDOW; want_check_exit = dec_entry_refcnt(adb, entry, ISC_FALSE); UNLOCK(&adb->entrylocks[bucket]); addr->entry = NULL; free_adbaddrinfo(adb, &addr); if (want_check_exit) { LOCK(&adb->lock); check_exit(adb); UNLOCK(&adb->lock); } } void dns_adb_flush(dns_adb_t *adb) { unsigned int i; INSIST(DNS_ADB_VALID(adb)); LOCK(&adb->lock); /* * Call our cleanup routines. */ for (i = 0; i < NBUCKETS; i++) RUNTIME_CHECK(cleanup_names(adb, i, INT_MAX) == ISC_FALSE); for (i = 0; i < NBUCKETS; i++) RUNTIME_CHECK(cleanup_entries(adb, i, INT_MAX) == ISC_FALSE); #ifdef DUMP_ADB_AFTER_CLEANING dump_adb(adb, stdout, ISC_TRUE, INT_MAX); #endif UNLOCK(&adb->lock); } void dns_adb_flushname(dns_adb_t *adb, dns_name_t *name) { dns_adbname_t *adbname; dns_adbname_t *nextname; int bucket; INSIST(DNS_ADB_VALID(adb)); LOCK(&adb->lock); bucket = dns_name_hash(name, ISC_FALSE) % NBUCKETS; LOCK(&adb->namelocks[bucket]); adbname = ISC_LIST_HEAD(adb->names[bucket]); while (adbname != NULL) { nextname = ISC_LIST_NEXT(adbname, plink); if (!NAME_DEAD(adbname) && dns_name_equal(name, &adbname->name)) { RUNTIME_CHECK(kill_name(&adbname, DNS_EVENT_ADBCANCELED, ISC_TRUE) == ISC_FALSE); } adbname = nextname; } UNLOCK(&adb->namelocks[bucket]); UNLOCK(&adb->lock); } static void water(void *arg, int mark) { dns_adb_t *adb = arg; isc_boolean_t overmem = ISC_TF(mark == ISC_MEM_HIWATER); REQUIRE(DNS_ADB_VALID(adb)); DP(ISC_LOG_DEBUG(1), "adb reached %s water mark", overmem ? "high" : "low"); /* * We can't use adb->lock as there is potential for water * to be called when adb->lock is held. */ LOCK(&adb->overmemlock); if (adb->overmem != overmem) { adb->overmem = overmem; isc_mem_waterack(adb->mctx, mark); } UNLOCK(&adb->overmemlock); } void dns_adb_setadbsize(dns_adb_t *adb, isc_uint32_t size) { isc_uint32_t hiwater; isc_uint32_t lowater; INSIST(DNS_ADB_VALID(adb)); if (size != 0 && size < DNS_ADB_MINADBSIZE) size = DNS_ADB_MINADBSIZE; hiwater = size - (size >> 3); /* Approximately 7/8ths. */ lowater = size - (size >> 2); /* Approximately 3/4ths. */ if (size == 0 || hiwater == 0 || lowater == 0) isc_mem_setwater(adb->mctx, water, adb, 0, 0); else isc_mem_setwater(adb->mctx, water, adb, hiwater, lowater); }