/* * Copyright (C) 2004-2006 Internet Systems Consortium, Inc. ("ISC") * Copyright (C) 1999-2003 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 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: query.c,v 1.198.2.13.4.43 2006/08/31 03:57:11 marka Exp $ */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define PARTIALANSWER(c) (((c)->query.attributes & \ NS_QUERYATTR_PARTIALANSWER) != 0) #define USECACHE(c) (((c)->query.attributes & \ NS_QUERYATTR_CACHEOK) != 0) #define RECURSIONOK(c) (((c)->query.attributes & \ NS_QUERYATTR_RECURSIONOK) != 0) #define RECURSING(c) (((c)->query.attributes & \ NS_QUERYATTR_RECURSING) != 0) #define CACHEGLUEOK(c) (((c)->query.attributes & \ NS_QUERYATTR_CACHEGLUEOK) != 0) #define WANTRECURSION(c) (((c)->query.attributes & \ NS_QUERYATTR_WANTRECURSION) != 0) #define WANTDNSSEC(c) (((c)->attributes & \ NS_CLIENTATTR_WANTDNSSEC) != 0) #define NOAUTHORITY(c) (((c)->query.attributes & \ NS_QUERYATTR_NOAUTHORITY) != 0) #define NOADDITIONAL(c) (((c)->query.attributes & \ NS_QUERYATTR_NOADDITIONAL) != 0) #define SECURE(c) (((c)->query.attributes & \ NS_QUERYATTR_SECURE) != 0) #if 0 #define CTRACE(m) isc_log_write(ns_g_lctx, \ NS_LOGCATEGORY_CLIENT, \ NS_LOGMODULE_QUERY, \ ISC_LOG_DEBUG(3), \ "client %p: %s", client, (m)) #define QTRACE(m) isc_log_write(ns_g_lctx, \ NS_LOGCATEGORY_GENERAL, \ NS_LOGMODULE_QUERY, \ ISC_LOG_DEBUG(3), \ "query %p: %s", query, (m)) #else #define CTRACE(m) ((void)m) #define QTRACE(m) ((void)m) #endif #define DNS_GETDB_NOEXACT 0x01U #define DNS_GETDB_NOLOG 0x02U #define DNS_GETDB_PARTIAL 0x04U static void query_find(ns_client_t *client, dns_fetchevent_t *event, dns_rdatatype_t qtype); /* * Increment query statistics counters. */ static inline void inc_stats(ns_client_t *client, dns_statscounter_t counter) { dns_zone_t *zone = client->query.authzone; REQUIRE(counter < DNS_STATS_NCOUNTERS); ns_g_server->querystats[counter]++; if (zone != NULL) { isc_uint64_t *zonestats = dns_zone_getstatscounters(zone); if (zonestats != NULL) zonestats[counter]++; } } static void query_send(ns_client_t *client) { dns_statscounter_t counter; if (client->message->rcode == dns_rcode_noerror) { if (ISC_LIST_EMPTY(client->message->sections[DNS_SECTION_ANSWER])) { if (client->query.isreferral) { counter = dns_statscounter_referral; } else { counter = dns_statscounter_nxrrset; } } else { counter = dns_statscounter_success; } } else if (client->message->rcode == dns_rcode_nxdomain) { counter = dns_statscounter_nxdomain; } else { /* We end up here in case of YXDOMAIN, and maybe others */ counter = dns_statscounter_failure; } inc_stats(client, counter); ns_client_send(client); } static void query_error(ns_client_t *client, isc_result_t result) { inc_stats(client, dns_statscounter_failure); ns_client_error(client, result); } static void query_next(ns_client_t *client, isc_result_t result) { inc_stats(client, dns_statscounter_failure); ns_client_next(client, result); } static inline void query_freefreeversions(ns_client_t *client, isc_boolean_t everything) { ns_dbversion_t *dbversion, *dbversion_next; unsigned int i; for (dbversion = ISC_LIST_HEAD(client->query.freeversions), i = 0; dbversion != NULL; dbversion = dbversion_next, i++) { dbversion_next = ISC_LIST_NEXT(dbversion, link); /* * If we're not freeing everything, we keep the first three * dbversions structures around. */ if (i > 3 || everything) { ISC_LIST_UNLINK(client->query.freeversions, dbversion, link); isc_mem_put(client->mctx, dbversion, sizeof(*dbversion)); } } } void ns_query_cancel(ns_client_t *client) { LOCK(&client->query.fetchlock); if (client->query.fetch != NULL) { dns_resolver_cancelfetch(client->query.fetch); client->query.fetch = NULL; } UNLOCK(&client->query.fetchlock); } static inline void query_reset(ns_client_t *client, isc_boolean_t everything) { isc_buffer_t *dbuf, *dbuf_next; ns_dbversion_t *dbversion, *dbversion_next; /* * Reset the query state of a client to its default state. */ /* * Cancel the fetch if it's running. */ ns_query_cancel(client); /* * Cleanup any active versions. */ for (dbversion = ISC_LIST_HEAD(client->query.activeversions); dbversion != NULL; dbversion = dbversion_next) { dbversion_next = ISC_LIST_NEXT(dbversion, link); dns_db_closeversion(dbversion->db, &dbversion->version, ISC_FALSE); dns_db_detach(&dbversion->db); ISC_LIST_INITANDAPPEND(client->query.freeversions, dbversion, link); } ISC_LIST_INIT(client->query.activeversions); if (client->query.authdb != NULL) dns_db_detach(&client->query.authdb); if (client->query.authzone != NULL) dns_zone_detach(&client->query.authzone); query_freefreeversions(client, everything); for (dbuf = ISC_LIST_HEAD(client->query.namebufs); dbuf != NULL; dbuf = dbuf_next) { dbuf_next = ISC_LIST_NEXT(dbuf, link); if (dbuf_next != NULL || everything) { ISC_LIST_UNLINK(client->query.namebufs, dbuf, link); isc_buffer_free(&dbuf); } } if (client->query.restarts > 0) { /* * client->query.qname was dynamically allocated. */ dns_message_puttempname(client->message, &client->query.qname); } client->query.qname = NULL; client->query.attributes = (NS_QUERYATTR_RECURSIONOK | NS_QUERYATTR_CACHEOK | NS_QUERYATTR_SECURE); client->query.restarts = 0; client->query.timerset = ISC_FALSE; client->query.origqname = NULL; client->query.qname = NULL; client->query.dboptions = 0; client->query.fetchoptions = 0; client->query.gluedb = NULL; client->query.authdbset = ISC_FALSE; client->query.isreferral = ISC_FALSE; } static void query_next_callback(ns_client_t *client) { query_reset(client, ISC_FALSE); } void ns_query_free(ns_client_t *client) { query_reset(client, ISC_TRUE); } static inline isc_result_t query_newnamebuf(ns_client_t *client) { isc_buffer_t *dbuf; isc_result_t result; CTRACE("query_newnamebuf"); /* * Allocate a name buffer. */ dbuf = NULL; result = isc_buffer_allocate(client->mctx, &dbuf, 1024); if (result != ISC_R_SUCCESS) { CTRACE("query_newnamebuf: isc_buffer_allocate failed: done"); return (result); } ISC_LIST_APPEND(client->query.namebufs, dbuf, link); CTRACE("query_newnamebuf: done"); return (ISC_R_SUCCESS); } static inline isc_buffer_t * query_getnamebuf(ns_client_t *client) { isc_buffer_t *dbuf; isc_result_t result; isc_region_t r; CTRACE("query_getnamebuf"); /* * Return a name buffer with space for a maximal name, allocating * a new one if necessary. */ if (ISC_LIST_EMPTY(client->query.namebufs)) { result = query_newnamebuf(client); if (result != ISC_R_SUCCESS) { CTRACE("query_getnamebuf: query_newnamebuf failed: done"); return (NULL); } } dbuf = ISC_LIST_TAIL(client->query.namebufs); INSIST(dbuf != NULL); isc_buffer_availableregion(dbuf, &r); if (r.length < 255) { result = query_newnamebuf(client); if (result != ISC_R_SUCCESS) { CTRACE("query_getnamebuf: query_newnamebuf failed: done"); return (NULL); } dbuf = ISC_LIST_TAIL(client->query.namebufs); isc_buffer_availableregion(dbuf, &r); INSIST(r.length >= 255); } CTRACE("query_getnamebuf: done"); return (dbuf); } static inline void query_keepname(ns_client_t *client, dns_name_t *name, isc_buffer_t *dbuf) { isc_region_t r; CTRACE("query_keepname"); /* * 'name' is using space in 'dbuf', but 'dbuf' has not yet been * adjusted to take account of that. We do the adjustment. */ REQUIRE((client->query.attributes & NS_QUERYATTR_NAMEBUFUSED) != 0); dns_name_toregion(name, &r); isc_buffer_add(dbuf, r.length); dns_name_setbuffer(name, NULL); client->query.attributes &= ~NS_QUERYATTR_NAMEBUFUSED; } static inline void query_releasename(ns_client_t *client, dns_name_t **namep) { dns_name_t *name = *namep; /* * 'name' is no longer needed. Return it to our pool of temporary * names. If it is using a name buffer, relinquish its exclusive * rights on the buffer. */ CTRACE("query_releasename"); if (dns_name_hasbuffer(name)) { INSIST((client->query.attributes & NS_QUERYATTR_NAMEBUFUSED) != 0); client->query.attributes &= ~NS_QUERYATTR_NAMEBUFUSED; } dns_message_puttempname(client->message, namep); CTRACE("query_releasename: done"); } static inline dns_name_t * query_newname(ns_client_t *client, isc_buffer_t *dbuf, isc_buffer_t *nbuf) { dns_name_t *name; isc_region_t r; isc_result_t result; REQUIRE((client->query.attributes & NS_QUERYATTR_NAMEBUFUSED) == 0); CTRACE("query_newname"); name = NULL; result = dns_message_gettempname(client->message, &name); if (result != ISC_R_SUCCESS) { CTRACE("query_newname: dns_message_gettempname failed: done"); return (NULL); } isc_buffer_availableregion(dbuf, &r); isc_buffer_init(nbuf, r.base, r.length); dns_name_init(name, NULL); dns_name_setbuffer(name, nbuf); client->query.attributes |= NS_QUERYATTR_NAMEBUFUSED; CTRACE("query_newname: done"); return (name); } static inline dns_rdataset_t * query_newrdataset(ns_client_t *client) { dns_rdataset_t *rdataset; isc_result_t result; CTRACE("query_newrdataset"); rdataset = NULL; result = dns_message_gettemprdataset(client->message, &rdataset); if (result != ISC_R_SUCCESS) { CTRACE("query_newrdataset: " "dns_message_gettemprdataset failed: done"); return (NULL); } dns_rdataset_init(rdataset); CTRACE("query_newrdataset: done"); return (rdataset); } static inline void query_putrdataset(ns_client_t *client, dns_rdataset_t **rdatasetp) { dns_rdataset_t *rdataset = *rdatasetp; CTRACE("query_putrdataset"); if (rdataset != NULL) { if (dns_rdataset_isassociated(rdataset)) dns_rdataset_disassociate(rdataset); dns_message_puttemprdataset(client->message, rdatasetp); } CTRACE("query_putrdataset: done"); } static inline isc_result_t query_newdbversion(ns_client_t *client, unsigned int n) { unsigned int i; ns_dbversion_t *dbversion; for (i = 0; i < n; i++) { dbversion = isc_mem_get(client->mctx, sizeof(*dbversion)); if (dbversion != NULL) { dbversion->db = NULL; dbversion->version = NULL; ISC_LIST_INITANDAPPEND(client->query.freeversions, dbversion, link); } else { /* * We only return ISC_R_NOMEMORY if we couldn't * allocate anything. */ if (i == 0) return (ISC_R_NOMEMORY); else return (ISC_R_SUCCESS); } } return (ISC_R_SUCCESS); } static inline ns_dbversion_t * query_getdbversion(ns_client_t *client) { isc_result_t result; ns_dbversion_t *dbversion; if (ISC_LIST_EMPTY(client->query.freeversions)) { result = query_newdbversion(client, 1); if (result != ISC_R_SUCCESS) return (NULL); } dbversion = ISC_LIST_HEAD(client->query.freeversions); INSIST(dbversion != NULL); ISC_LIST_UNLINK(client->query.freeversions, dbversion, link); return (dbversion); } isc_result_t ns_query_init(ns_client_t *client) { isc_result_t result; ISC_LIST_INIT(client->query.namebufs); ISC_LIST_INIT(client->query.activeversions); ISC_LIST_INIT(client->query.freeversions); client->query.restarts = 0; client->query.timerset = ISC_FALSE; client->query.qname = NULL; result = isc_mutex_init(&client->query.fetchlock); if (result != ISC_R_SUCCESS) return (result); client->query.fetch = NULL; client->query.authdb = NULL; client->query.authzone = NULL; client->query.authdbset = ISC_FALSE; client->query.isreferral = ISC_FALSE; query_reset(client, ISC_FALSE); result = query_newdbversion(client, 3); if (result != ISC_R_SUCCESS) { DESTROYLOCK(&client->query.fetchlock); return (result); } result = query_newnamebuf(client); if (result != ISC_R_SUCCESS) query_freefreeversions(client, ISC_TRUE); return (result); } static inline ns_dbversion_t * query_findversion(ns_client_t *client, dns_db_t *db, isc_boolean_t *newzonep) { ns_dbversion_t *dbversion; /* * We may already have done a query related to this * database. If so, we must be sure to make subsequent * queries from the same version. */ for (dbversion = ISC_LIST_HEAD(client->query.activeversions); dbversion != NULL; dbversion = ISC_LIST_NEXT(dbversion, link)) { if (dbversion->db == db) break; } if (dbversion == NULL) { /* * This is a new zone for this query. Add it to * the active list. */ dbversion = query_getdbversion(client); if (dbversion == NULL) return (NULL); dns_db_attach(db, &dbversion->db); dns_db_currentversion(db, &dbversion->version); dbversion->queryok = ISC_FALSE; ISC_LIST_APPEND(client->query.activeversions, dbversion, link); *newzonep = ISC_TRUE; } else *newzonep = ISC_FALSE; return (dbversion); } static inline isc_result_t query_getzonedb(ns_client_t *client, dns_name_t *name, dns_rdatatype_t qtype, unsigned int options, dns_zone_t **zonep, dns_db_t **dbp, dns_dbversion_t **versionp) { isc_result_t result; isc_boolean_t check_acl, new_zone; dns_acl_t *queryacl; ns_dbversion_t *dbversion; unsigned int ztoptions; dns_zone_t *zone = NULL; dns_db_t *db = NULL; isc_boolean_t partial = ISC_FALSE; REQUIRE(zonep != NULL && *zonep == NULL); REQUIRE(dbp != NULL && *dbp == NULL); /* * Find a zone database to answer the query. */ ztoptions = ((options & DNS_GETDB_NOEXACT) != 0) ? DNS_ZTFIND_NOEXACT : 0; result = dns_zt_find(client->view->zonetable, name, ztoptions, NULL, &zone); if (result == DNS_R_PARTIALMATCH) partial = ISC_TRUE; if (result == ISC_R_SUCCESS || result == DNS_R_PARTIALMATCH) result = dns_zone_getdb(zone, &db); if (result != ISC_R_SUCCESS) goto fail; /* * This limits our searching to the zone where the first name * (the query target) was looked for. This prevents following * CNAMES or DNAMES into other zones and prevents returning * additional data from other zones. */ if (!client->view->additionalfromauth && client->query.authdbset && db != client->query.authdb) goto refuse; /* * If the zone has an ACL, we'll check it, otherwise * we use the view's "allow-query" ACL. Each ACL is only checked * once per query. * * Also, get the database version to use. */ check_acl = ISC_TRUE; /* Keep compiler happy. */ queryacl = NULL; /* * Get the current version of this database. */ dbversion = query_findversion(client, db, &new_zone); if (dbversion == NULL) { result = DNS_R_SERVFAIL; goto fail; } if (new_zone) { check_acl = ISC_TRUE; } else if (!dbversion->queryok) { goto refuse; } else { check_acl = ISC_FALSE; } queryacl = dns_zone_getqueryacl(zone); if (queryacl == NULL) { queryacl = client->view->queryacl; if ((client->query.attributes & NS_QUERYATTR_QUERYOKVALID) != 0) { /* * We've evaluated the view's queryacl already. If * NS_QUERYATTR_QUERYOK is set, then the client is * allowed to make queries, otherwise the query should * be refused. */ check_acl = ISC_FALSE; if ((client->query.attributes & NS_QUERYATTR_QUERYOK) == 0) goto refuse; } else { /* * We haven't evaluated the view's queryacl yet. */ check_acl = ISC_TRUE; } } if (check_acl) { isc_boolean_t log = ISC_TF((options & DNS_GETDB_NOLOG) == 0); result = ns_client_checkaclsilent(client, queryacl, ISC_TRUE); if (log) { char msg[NS_CLIENT_ACLMSGSIZE("query")]; if (result == ISC_R_SUCCESS) { if (isc_log_wouldlog(ns_g_lctx, ISC_LOG_DEBUG(3))) { ns_client_aclmsg("query", name, qtype, client->view->rdclass, msg, sizeof(msg)); ns_client_log(client, DNS_LOGCATEGORY_SECURITY, NS_LOGMODULE_QUERY, ISC_LOG_DEBUG(3), "%s approved", msg); } } else { ns_client_aclmsg("query", name, qtype, client->view->rdclass, msg, sizeof(msg)); ns_client_log(client, DNS_LOGCATEGORY_SECURITY, NS_LOGMODULE_QUERY, ISC_LOG_INFO, "%s denied", msg); } } if (queryacl == client->view->queryacl) { if (result == ISC_R_SUCCESS) { /* * We were allowed by the default * "allow-query" ACL. Remember this so we * don't have to check again. */ client->query.attributes |= NS_QUERYATTR_QUERYOK; } /* * We've now evaluated the view's query ACL, and * the NS_QUERYATTR_QUERYOK attribute is now valid. */ client->query.attributes |= NS_QUERYATTR_QUERYOKVALID; } if (result != ISC_R_SUCCESS) goto refuse; } /* Approved. */ /* * Remember the result of the ACL check so we * don't have to check again. */ dbversion->queryok = ISC_TRUE; /* Transfer ownership. */ *zonep = zone; *dbp = db; *versionp = dbversion->version; if (partial && (options & DNS_GETDB_PARTIAL) != 0) return (DNS_R_PARTIALMATCH); return (ISC_R_SUCCESS); refuse: result = DNS_R_REFUSED; fail: if (zone != NULL) dns_zone_detach(&zone); if (db != NULL) dns_db_detach(&db); return (result); } static inline isc_result_t query_getcachedb(ns_client_t *client, dns_name_t *name, dns_rdatatype_t qtype, dns_db_t **dbp, unsigned int options) { isc_result_t result; isc_boolean_t check_acl; dns_db_t *db = NULL; REQUIRE(dbp != NULL && *dbp == NULL); /* * Find a cache database to answer the query. * This may fail with DNS_R_REFUSED if the client * is not allowed to use the cache. */ if (!USECACHE(client)) return (DNS_R_REFUSED); dns_db_attach(client->view->cachedb, &db); if ((client->query.attributes & NS_QUERYATTR_QUERYOKVALID) != 0) { /* * We've evaluated the view's queryacl already. If * NS_QUERYATTR_QUERYOK is set, then the client is * allowed to make queries, otherwise the query should * be refused. */ check_acl = ISC_FALSE; if ((client->query.attributes & NS_QUERYATTR_QUERYOK) == 0) goto refuse; } else { /* * We haven't evaluated the view's queryacl yet. */ check_acl = ISC_TRUE; } if (check_acl) { isc_boolean_t log = ISC_TF((options & DNS_GETDB_NOLOG) == 0); char msg[NS_CLIENT_ACLMSGSIZE("query (cache)")]; result = ns_client_checkaclsilent(client, client->view->queryacl, ISC_TRUE); if (result == ISC_R_SUCCESS) { /* * We were allowed by the default * "allow-query" ACL. Remember this so we * don't have to check again. */ client->query.attributes |= NS_QUERYATTR_QUERYOK; if (log && isc_log_wouldlog(ns_g_lctx, ISC_LOG_DEBUG(3))) { ns_client_aclmsg("query (cache)", name, qtype, client->view->rdclass, msg, sizeof(msg)); ns_client_log(client, DNS_LOGCATEGORY_SECURITY, NS_LOGMODULE_QUERY, ISC_LOG_DEBUG(3), "%s approved", msg); } } else if (log) { ns_client_aclmsg("query (cache)", name, qtype, client->view->rdclass, msg, sizeof(msg)); ns_client_log(client, DNS_LOGCATEGORY_SECURITY, NS_LOGMODULE_QUERY, ISC_LOG_INFO, "%s denied", msg); } /* * We've now evaluated the view's query ACL, and * the NS_QUERYATTR_QUERYOK attribute is now valid. */ client->query.attributes |= NS_QUERYATTR_QUERYOKVALID; if (result != ISC_R_SUCCESS) goto refuse; } /* Approved. */ /* Transfer ownership. */ *dbp = db; return (ISC_R_SUCCESS); refuse: result = DNS_R_REFUSED; if (db != NULL) dns_db_detach(&db); return (result); } static inline isc_result_t query_getdb(ns_client_t *client, dns_name_t *name, dns_rdatatype_t qtype, unsigned int options, dns_zone_t **zonep, dns_db_t **dbp, dns_dbversion_t **versionp, isc_boolean_t *is_zonep) { isc_result_t result; result = query_getzonedb(client, name, qtype, options, zonep, dbp, versionp); if (result == ISC_R_SUCCESS) { *is_zonep = ISC_TRUE; } else if (result == ISC_R_NOTFOUND) { result = query_getcachedb(client, name, qtype, dbp, options); *is_zonep = ISC_FALSE; } return (result); } static inline isc_boolean_t query_isduplicate(ns_client_t *client, dns_name_t *name, dns_rdatatype_t type, dns_name_t **mnamep) { dns_section_t section; dns_name_t *mname = NULL; isc_result_t result; CTRACE("query_isduplicate"); for (section = DNS_SECTION_ANSWER; section <= DNS_SECTION_ADDITIONAL; section++) { result = dns_message_findname(client->message, section, name, type, 0, &mname, NULL); if (result == ISC_R_SUCCESS) { /* * We've already got this RRset in the response. */ CTRACE("query_isduplicate: true: done"); return (ISC_TRUE); } else if (result == DNS_R_NXRRSET) { /* * The name exists, but the rdataset does not. */ if (section == DNS_SECTION_ADDITIONAL) break; } else RUNTIME_CHECK(result == DNS_R_NXDOMAIN); mname = NULL; } /* * If the dns_name_t we're looking up is already in the message, * we don't want to trigger the caller's name replacement logic. */ if (name == mname) mname = NULL; *mnamep = mname; CTRACE("query_isduplicate: false: done"); return (ISC_FALSE); } static isc_result_t query_addadditional(void *arg, dns_name_t *name, dns_rdatatype_t qtype) { ns_client_t *client = arg; isc_result_t result, eresult; dns_dbnode_t *node; dns_db_t *db; dns_name_t *fname, *mname; dns_rdataset_t *rdataset, *sigrdataset, *trdataset; isc_buffer_t *dbuf; isc_buffer_t b; dns_dbversion_t *version; isc_boolean_t added_something, need_addname; dns_zone_t *zone; dns_rdatatype_t type; REQUIRE(NS_CLIENT_VALID(client)); REQUIRE(qtype != dns_rdatatype_any); if (!WANTDNSSEC(client) && dns_rdatatype_isdnssec(qtype)) return (ISC_R_SUCCESS); CTRACE("query_addadditional"); /* * Initialization. */ eresult = ISC_R_SUCCESS; fname = NULL; rdataset = NULL; sigrdataset = NULL; trdataset = NULL; db = NULL; version = NULL; node = NULL; added_something = ISC_FALSE; need_addname = ISC_FALSE; zone = NULL; /* * We treat type A additional section processing as if it * were "any address type" additional section processing. * To avoid multiple lookups, we do an 'any' database * lookup and iterate over the node. */ if (qtype == dns_rdatatype_a) type = dns_rdatatype_any; else type = qtype; /* * Get some resources. */ dbuf = query_getnamebuf(client); if (dbuf == NULL) goto cleanup; fname = query_newname(client, dbuf, &b); rdataset = query_newrdataset(client); if (fname == NULL || rdataset == NULL) goto cleanup; if (WANTDNSSEC(client)) { sigrdataset = query_newrdataset(client); if (sigrdataset == NULL) goto cleanup; } /* * Look for a zone database that might contain authoritative * additional data. */ result = query_getzonedb(client, name, qtype, DNS_GETDB_NOLOG, &zone, &db, &version); if (result != ISC_R_SUCCESS) goto try_cache; CTRACE("query_addadditional: db_find"); /* * Since we are looking for authoritative data, we do not set * the GLUEOK flag. Glue will be looked for later, but not * necessarily in the same database. */ node = NULL; result = dns_db_find(db, name, version, type, client->query.dboptions, client->now, &node, fname, rdataset, sigrdataset); if (result == ISC_R_SUCCESS) goto found; if (dns_rdataset_isassociated(rdataset)) dns_rdataset_disassociate(rdataset); if (sigrdataset != NULL && dns_rdataset_isassociated(sigrdataset)) dns_rdataset_disassociate(sigrdataset); if (node != NULL) dns_db_detachnode(db, &node); version = NULL; dns_db_detach(&db); /* * No authoritative data was found. The cache is our next best bet. */ try_cache: result = query_getcachedb(client, name, qtype, &db, DNS_GETDB_NOLOG); if (result != ISC_R_SUCCESS) /* * Most likely the client isn't allowed to query the cache. */ goto try_glue; result = dns_db_find(db, name, version, type, client->query.dboptions, client->now, &node, fname, rdataset, sigrdataset); if (result == ISC_R_SUCCESS) goto found; if (dns_rdataset_isassociated(rdataset)) dns_rdataset_disassociate(rdataset); if (sigrdataset != NULL && dns_rdataset_isassociated(sigrdataset)) dns_rdataset_disassociate(sigrdataset); if (node != NULL) dns_db_detachnode(db, &node); dns_db_detach(&db); try_glue: /* * No cached data was found. Glue is our last chance. * RFC1035 sayeth: * * NS records cause both the usual additional section * processing to locate a type A record, and, when used * in a referral, a special search of the zone in which * they reside for glue information. * * This is the "special search". Note that we must search * the zone where the NS record resides, not the zone it * points to, and that we only do the search in the delegation * case (identified by client->query.gluedb being set). */ if (client->query.gluedb == NULL) goto cleanup; /* * Don't poision caches using the bailiwick protection model. */ if (!dns_name_issubdomain(name, dns_db_origin(client->query.gluedb))) goto cleanup; dns_db_attach(client->query.gluedb, &db); result = dns_db_find(db, name, version, type, client->query.dboptions | DNS_DBFIND_GLUEOK, client->now, &node, fname, rdataset, sigrdataset); if (!(result == ISC_R_SUCCESS || result == DNS_R_ZONECUT || result == DNS_R_GLUE)) goto cleanup; found: /* * We have found a potential additional data rdataset, or * at least a node to iterate over. */ query_keepname(client, fname, dbuf); /* * If we have an rdataset, add it to the additional data * section. */ mname = NULL; if (dns_rdataset_isassociated(rdataset) && !query_isduplicate(client, fname, type, &mname)) { if (mname != NULL) { query_releasename(client, &fname); fname = mname; } else need_addname = ISC_TRUE; ISC_LIST_APPEND(fname->list, rdataset, link); trdataset = rdataset; rdataset = NULL; added_something = ISC_TRUE; /* * Note: we only add SIGs if we've added the type they cover, * so we do not need to check if the SIG rdataset is already * in the response. */ if (sigrdataset != NULL && dns_rdataset_isassociated(sigrdataset)) { ISC_LIST_APPEND(fname->list, sigrdataset, link); sigrdataset = NULL; } } if (qtype == dns_rdatatype_a) { /* * We now go looking for A and AAAA records, along with * their signatures. * * XXXRTH This code could be more efficient. */ if (rdataset != NULL) { if (dns_rdataset_isassociated(rdataset)) dns_rdataset_disassociate(rdataset); } else { rdataset = query_newrdataset(client); if (rdataset == NULL) goto addname; } if (sigrdataset != NULL) { if (dns_rdataset_isassociated(sigrdataset)) dns_rdataset_disassociate(sigrdataset); } else if (WANTDNSSEC(client)) { sigrdataset = query_newrdataset(client); if (sigrdataset == NULL) goto addname; } result = dns_db_findrdataset(db, node, version, dns_rdatatype_a, 0, client->now, rdataset, sigrdataset); if (result == DNS_R_NCACHENXDOMAIN) goto addname; if (result == DNS_R_NCACHENXRRSET) { dns_rdataset_disassociate(rdataset); /* * Negative cache entries don't have sigrdatasets. */ INSIST(sigrdataset == NULL || ! dns_rdataset_isassociated(sigrdataset)); } if (result == ISC_R_SUCCESS) { mname = NULL; if (!query_isduplicate(client, fname, dns_rdatatype_a, &mname)) { if (mname != NULL) { query_releasename(client, &fname); fname = mname; } else need_addname = ISC_TRUE; ISC_LIST_APPEND(fname->list, rdataset, link); added_something = ISC_TRUE; if (sigrdataset != NULL && dns_rdataset_isassociated(sigrdataset)) { ISC_LIST_APPEND(fname->list, sigrdataset, link); sigrdataset = query_newrdataset(client); } rdataset = query_newrdataset(client); if (rdataset == NULL) goto addname; if (WANTDNSSEC(client) && sigrdataset == NULL) goto addname; } else { dns_rdataset_disassociate(rdataset); if (sigrdataset != NULL && dns_rdataset_isassociated(sigrdataset)) dns_rdataset_disassociate(sigrdataset); } } result = dns_db_findrdataset(db, node, version, dns_rdatatype_aaaa, 0, client->now, rdataset, sigrdataset); if (result == DNS_R_NCACHENXDOMAIN) goto addname; if (result == DNS_R_NCACHENXRRSET) { dns_rdataset_disassociate(rdataset); INSIST(sigrdataset == NULL || ! dns_rdataset_isassociated(sigrdataset)); } if (result == ISC_R_SUCCESS) { mname = NULL; if (!query_isduplicate(client, fname, dns_rdatatype_aaaa, &mname)) { if (mname != NULL) { query_releasename(client, &fname); fname = mname; } else need_addname = ISC_TRUE; ISC_LIST_APPEND(fname->list, rdataset, link); added_something = ISC_TRUE; if (sigrdataset != NULL && dns_rdataset_isassociated(sigrdataset)) { ISC_LIST_APPEND(fname->list, sigrdataset, link); sigrdataset = NULL; } rdataset = NULL; } } } addname: CTRACE("query_addadditional: addname"); /* * If we haven't added anything, then we're done. */ if (!added_something) goto cleanup; /* * We may have added our rdatasets to an existing name, if so, then * need_addname will be ISC_FALSE. Whether we used an existing name * or a new one, we must set fname to NULL to prevent cleanup. */ if (need_addname) dns_message_addname(client->message, fname, DNS_SECTION_ADDITIONAL); fname = NULL; /* * In a few cases, we want to add additional data for additional * data. It's simpler to just deal with special cases here than * to try to create a general purpose mechanism and allow the * rdata implementations to do it themselves. * * This involves recursion, but the depth is limited. The * most complex case is adding a SRV rdataset, which involves * recursing to add address records, which in turn can cause * recursion to add KEYs. */ if (type == dns_rdatatype_srv && trdataset != NULL) { /* * If we're adding SRV records to the additional data * section, it's helpful if we add the SRV additional data * as well. */ eresult = dns_rdataset_additionaldata(trdataset, query_addadditional, client); } cleanup: CTRACE("query_addadditional: cleanup"); query_putrdataset(client, &rdataset); if (sigrdataset != NULL) query_putrdataset(client, &sigrdataset); if (fname != NULL) query_releasename(client, &fname); if (node != NULL) dns_db_detachnode(db, &node); if (db != NULL) dns_db_detach(&db); if (zone != NULL) dns_zone_detach(&zone); CTRACE("query_addadditional: done"); return (eresult); } static inline void query_addrdataset(ns_client_t *client, dns_name_t *fname, dns_rdataset_t *rdataset) { /* * Add 'rdataset' and any pertinent additional data to * 'fname', a name in the response message for 'client'. */ CTRACE("query_addrdataset"); ISC_LIST_APPEND(fname->list, rdataset, link); if (client->view->order != NULL) rdataset->attributes |= dns_order_find(client->view->order, fname, rdataset->type, rdataset->rdclass); if (NOADDITIONAL(client)) return; /* * Add additional data. * * We don't care if dns_rdataset_additionaldata() fails. */ (void)dns_rdataset_additionaldata(rdataset, query_addadditional, client); CTRACE("query_addrdataset: done"); } static void query_addrrset(ns_client_t *client, dns_name_t **namep, dns_rdataset_t **rdatasetp, dns_rdataset_t **sigrdatasetp, isc_buffer_t *dbuf, dns_section_t section) { dns_name_t *name, *mname; dns_rdataset_t *rdataset, *mrdataset, *sigrdataset; isc_result_t result; /* * To the current response for 'client', add the answer RRset * '*rdatasetp' and an optional signature set '*sigrdatasetp', with * owner name '*namep', to section 'section', unless they are * already there. Also add any pertinent additional data. * * If 'dbuf' is not NULL, then '*namep' is the name whose data is * stored in 'dbuf'. In this case, query_addrrset() guarantees that * when it returns the name will either have been kept or released. */ CTRACE("query_addrrset"); name = *namep; rdataset = *rdatasetp; if (sigrdatasetp != NULL) sigrdataset = *sigrdatasetp; else sigrdataset = NULL; mname = NULL; mrdataset = NULL; result = dns_message_findname(client->message, section, name, rdataset->type, rdataset->covers, &mname, &mrdataset); if (result == ISC_R_SUCCESS) { /* * We've already got an RRset of the given name and type. * There's nothing else to do; */ CTRACE("query_addrrset: dns_message_findname succeeded: done"); if (dbuf != NULL) query_releasename(client, namep); return; } else if (result == DNS_R_NXDOMAIN) { /* * The name doesn't exist. */ if (dbuf != NULL) query_keepname(client, name, dbuf); dns_message_addname(client->message, name, section); *namep = NULL; mname = name; } else { RUNTIME_CHECK(result == DNS_R_NXRRSET); if (dbuf != NULL) query_releasename(client, namep); } if (rdataset->trust != dns_trust_secure && (section == DNS_SECTION_ANSWER || section == DNS_SECTION_AUTHORITY)) client->query.attributes &= ~NS_QUERYATTR_SECURE; /* * Note: we only add SIGs if we've added the type they cover, so * we do not need to check if the SIG rdataset is already in the * response. */ query_addrdataset(client, mname, rdataset); *rdatasetp = NULL; if (sigrdataset != NULL && dns_rdataset_isassociated(sigrdataset)) { /* * We have a signature. Add it to the response. */ ISC_LIST_APPEND(mname->list, sigrdataset, link); *sigrdatasetp = NULL; } CTRACE("query_addrrset: done"); } static inline isc_result_t query_addsoa(ns_client_t *client, dns_db_t *db, isc_boolean_t zero_ttl) { dns_name_t *name, *fname; dns_dbnode_t *node; isc_result_t result, eresult; dns_fixedname_t foundname; dns_rdataset_t *rdataset = NULL, *sigrdataset = NULL; dns_rdataset_t **sigrdatasetp = NULL; CTRACE("query_addsoa"); /* * Initialization. */ eresult = ISC_R_SUCCESS; name = NULL; rdataset = NULL; node = NULL; dns_fixedname_init(&foundname); fname = dns_fixedname_name(&foundname); /* * Get resources and make 'name' be the database origin. */ result = dns_message_gettempname(client->message, &name); if (result != ISC_R_SUCCESS) return (result); dns_name_init(name, NULL); dns_name_clone(dns_db_origin(db), name); rdataset = query_newrdataset(client); if (rdataset == NULL) { eresult = DNS_R_SERVFAIL; goto cleanup; } if (WANTDNSSEC(client)) { sigrdataset = query_newrdataset(client); if (sigrdataset == NULL) { eresult = DNS_R_SERVFAIL; goto cleanup; } } /* * Find the SOA. */ result = dns_db_find(db, name, NULL, dns_rdatatype_soa, client->query.dboptions, 0, &node, fname, rdataset, sigrdataset); if (result != ISC_R_SUCCESS) { /* * This is bad. We tried to get the SOA RR at the zone top * and it didn't work! */ eresult = DNS_R_SERVFAIL; } else { /* * Extract the SOA MINIMUM. */ dns_rdata_soa_t soa; dns_rdata_t rdata = DNS_RDATA_INIT; result = dns_rdataset_first(rdataset); RUNTIME_CHECK(result == ISC_R_SUCCESS); dns_rdataset_current(rdataset, &rdata); result = dns_rdata_tostruct(&rdata, &soa, NULL); if (result != ISC_R_SUCCESS) goto cleanup; if (zero_ttl) { rdataset->ttl = 0; if (sigrdataset != NULL) sigrdataset->ttl = 0; } /* * Add the SOA and its SIG to the response, with the * TTLs adjusted per RFC2308 section 3. */ if (rdataset->ttl > soa.minimum) rdataset->ttl = soa.minimum; if (sigrdataset != NULL && sigrdataset->ttl > soa.minimum) sigrdataset->ttl = soa.minimum; if (sigrdataset != NULL) sigrdatasetp = &sigrdataset; else sigrdatasetp = NULL; query_addrrset(client, &name, &rdataset, sigrdatasetp, NULL, DNS_SECTION_AUTHORITY); } cleanup: query_putrdataset(client, &rdataset); if (sigrdataset != NULL) query_putrdataset(client, &sigrdataset); if (name != NULL) query_releasename(client, &name); if (node != NULL) dns_db_detachnode(db, &node); return (eresult); } static inline isc_result_t query_addns(ns_client_t *client, dns_db_t *db) { dns_name_t *name, *fname; dns_dbnode_t *node; isc_result_t result, eresult; dns_fixedname_t foundname; dns_rdataset_t *rdataset = NULL, *sigrdataset = NULL; dns_rdataset_t **sigrdatasetp = NULL; CTRACE("query_addns"); /* * Initialization. */ eresult = ISC_R_SUCCESS; name = NULL; rdataset = NULL; node = NULL; dns_fixedname_init(&foundname); fname = dns_fixedname_name(&foundname); /* * Get resources and make 'name' be the database origin. */ result = dns_message_gettempname(client->message, &name); if (result != ISC_R_SUCCESS) { CTRACE("query_addns: dns_message_gettempname failed: done"); return (result); } dns_name_init(name, NULL); dns_name_clone(dns_db_origin(db), name); rdataset = query_newrdataset(client); if (rdataset == NULL) { CTRACE("query_addns: query_newrdataset failed"); eresult = DNS_R_SERVFAIL; goto cleanup; } if (WANTDNSSEC(client)) { sigrdataset = query_newrdataset(client); if (sigrdataset == NULL) { CTRACE("query_addns: query_newrdataset failed"); eresult = DNS_R_SERVFAIL; goto cleanup; } } /* * Find the NS rdataset. */ CTRACE("query_addns: calling dns_db_find"); result = dns_db_find(db, name, NULL, dns_rdatatype_ns, client->query.dboptions, 0, &node, fname, rdataset, sigrdataset); CTRACE("query_addns: dns_db_find complete"); if (result != ISC_R_SUCCESS) { CTRACE("query_addns: dns_db_find failed"); /* * This is bad. We tried to get the NS rdataset at the zone * top and it didn't work! */ eresult = DNS_R_SERVFAIL; } else { if (sigrdataset != NULL) sigrdatasetp = &sigrdataset; else sigrdatasetp = NULL; query_addrrset(client, &name, &rdataset, sigrdatasetp, NULL, DNS_SECTION_AUTHORITY); } cleanup: CTRACE("query_addns: cleanup"); query_putrdataset(client, &rdataset); if (sigrdataset != NULL) query_putrdataset(client, &sigrdataset); if (name != NULL) query_releasename(client, &name); if (node != NULL) dns_db_detachnode(db, &node); CTRACE("query_addns: done"); return (eresult); } static inline isc_result_t query_addcnamelike(ns_client_t *client, dns_name_t *qname, dns_name_t *tname, dns_trust_t trust, dns_name_t **anamep, dns_rdatatype_t type) { dns_rdataset_t *rdataset; dns_rdatalist_t *rdatalist; dns_rdata_t *rdata; isc_result_t result; isc_region_t r; /* * We assume the name data referred to by tname won't go away. */ REQUIRE(anamep != NULL); rdatalist = NULL; result = dns_message_gettemprdatalist(client->message, &rdatalist); if (result != ISC_R_SUCCESS) return (result); rdata = NULL; result = dns_message_gettemprdata(client->message, &rdata); if (result != ISC_R_SUCCESS) return (result); rdataset = NULL; result = dns_message_gettemprdataset(client->message, &rdataset); if (result != ISC_R_SUCCESS) return (result); dns_rdataset_init(rdataset); result = dns_name_dup(qname, client->mctx, *anamep); if (result != ISC_R_SUCCESS) { dns_message_puttemprdataset(client->message, &rdataset); return (result); } rdatalist->type = type; rdatalist->covers = 0; rdatalist->rdclass = client->message->rdclass; rdatalist->ttl = 0; dns_name_toregion(tname, &r); rdata->data = r.base; rdata->length = r.length; rdata->rdclass = client->message->rdclass; rdata->type = type; ISC_LIST_INIT(rdatalist->rdata); ISC_LIST_APPEND(rdatalist->rdata, rdata, link); RUNTIME_CHECK(dns_rdatalist_tordataset(rdatalist, rdataset) == ISC_R_SUCCESS); rdataset->trust = trust; query_addrrset(client, anamep, &rdataset, NULL, NULL, DNS_SECTION_ANSWER); if (rdataset != NULL) { if (dns_rdataset_isassociated(rdataset)) dns_rdataset_disassociate(rdataset); dns_message_puttemprdataset(client->message, &rdataset); } return (ISC_R_SUCCESS); } static void query_addbestns(ns_client_t *client) { dns_db_t *db, *zdb; dns_dbnode_t *node; dns_name_t *fname, *zfname; dns_rdataset_t *rdataset, *sigrdataset, *zrdataset, *zsigrdataset; isc_boolean_t is_zone, use_zone; isc_buffer_t *dbuf; isc_result_t result; dns_dbversion_t *version; dns_zone_t *zone; isc_buffer_t b; CTRACE("query_addbestns"); fname = NULL; zfname = NULL; rdataset = NULL; zrdataset = NULL; sigrdataset = NULL; zsigrdataset = NULL; node = NULL; db = NULL; zdb = NULL; version = NULL; zone = NULL; is_zone = ISC_FALSE; use_zone = ISC_FALSE; /* * Find the right database. */ result = query_getdb(client, client->query.qname, dns_rdatatype_ns, 0, &zone, &db, &version, &is_zone); if (result != ISC_R_SUCCESS) goto cleanup; db_find: /* * We'll need some resources... */ dbuf = query_getnamebuf(client); if (dbuf == NULL) goto cleanup; fname = query_newname(client, dbuf, &b); rdataset = query_newrdataset(client); if (fname == NULL || rdataset == NULL) goto cleanup; if (WANTDNSSEC(client)) { sigrdataset = query_newrdataset(client); if (sigrdataset == NULL) goto cleanup; } /* * Now look for the zonecut. */ if (is_zone) { result = dns_db_find(db, client->query.qname, version, dns_rdatatype_ns, client->query.dboptions, client->now, &node, fname, rdataset, sigrdataset); if (result != DNS_R_DELEGATION) goto cleanup; if (USECACHE(client)) { query_keepname(client, fname, dbuf); zdb = db; zfname = fname; fname = NULL; zrdataset = rdataset; rdataset = NULL; zsigrdataset = sigrdataset; sigrdataset = NULL; dns_db_detachnode(db, &node); version = NULL; db = NULL; dns_db_attach(client->view->cachedb, &db); is_zone = ISC_FALSE; goto db_find; } } else { result = dns_db_findzonecut(db, client->query.qname, client->query.dboptions, client->now, &node, fname, rdataset, sigrdataset); if (result == ISC_R_SUCCESS) { if (zfname != NULL && !dns_name_issubdomain(fname, zfname)) { /* * We found a zonecut in the cache, but our * zone delegation is better. */ use_zone = ISC_TRUE; } } else if (result == ISC_R_NOTFOUND && zfname != NULL) { /* * We didn't find anything in the cache, but we * have a zone delegation, so use it. */ use_zone = ISC_TRUE; } else goto cleanup; } if (use_zone) { query_releasename(client, &fname); fname = zfname; zfname = NULL; /* * We've already done query_keepname() on * zfname, so we must set dbuf to NULL to * prevent query_addrrset() from trying to * call query_keepname() again. */ dbuf = NULL; query_putrdataset(client, &rdataset); if (sigrdataset != NULL) query_putrdataset(client, &sigrdataset); rdataset = zrdataset; zrdataset = NULL; sigrdataset = zsigrdataset; zsigrdataset = NULL; } if ((client->query.dboptions & DNS_DBFIND_PENDINGOK) == 0 && (rdataset->trust == dns_trust_pending || (sigrdataset != NULL && sigrdataset->trust == dns_trust_pending))) goto cleanup; if (WANTDNSSEC(client) && SECURE(client) && (rdataset->trust == dns_trust_glue || (sigrdataset != NULL && sigrdataset->trust == dns_trust_glue))) goto cleanup; query_addrrset(client, &fname, &rdataset, &sigrdataset, dbuf, DNS_SECTION_AUTHORITY); cleanup: if (rdataset != NULL) query_putrdataset(client, &rdataset); if (sigrdataset != NULL) query_putrdataset(client, &sigrdataset); if (fname != NULL) query_releasename(client, &fname); if (node != NULL) dns_db_detachnode(db, &node); if (db != NULL) dns_db_detach(&db); if (zone != NULL) dns_zone_detach(&zone); if (zdb != NULL) { query_putrdataset(client, &zrdataset); if (zsigrdataset != NULL) query_putrdataset(client, &zsigrdataset); if (zfname != NULL) query_releasename(client, &zfname); dns_db_detach(&zdb); } } static void query_addds(ns_client_t *client, dns_db_t *db, dns_dbnode_t *node) { dns_name_t *rname; dns_rdataset_t *rdataset, *sigrdataset; isc_result_t result; CTRACE("query_addds"); rname = NULL; rdataset = NULL; sigrdataset = NULL; /* * We'll need some resources... */ rdataset = query_newrdataset(client); sigrdataset = query_newrdataset(client); if (rdataset == NULL || sigrdataset == NULL) goto cleanup; /* * Look for the DS record, which may or may not be present. */ result = dns_db_findrdataset(db, node, NULL, dns_rdatatype_ds, 0, client->now, rdataset, sigrdataset); /* * If we didn't find it, look for an NSEC. */ if (result == ISC_R_NOTFOUND) result = dns_db_findrdataset(db, node, NULL, dns_rdatatype_nsec, 0, client->now, rdataset, sigrdataset); if (result != ISC_R_SUCCESS && result != ISC_R_NOTFOUND) goto cleanup; if (!dns_rdataset_isassociated(rdataset) || !dns_rdataset_isassociated(sigrdataset)) goto cleanup; /* * We've already added the NS record, so if the name's not there, * we have other problems. Use this name rather than calling * query_addrrset(). */ result = dns_message_firstname(client->message, DNS_SECTION_AUTHORITY); if (result != ISC_R_SUCCESS) goto cleanup; rname = NULL; dns_message_currentname(client->message, DNS_SECTION_AUTHORITY, &rname); result = dns_message_findtype(rname, dns_rdatatype_ns, 0, NULL); if (result != ISC_R_SUCCESS) goto cleanup; ISC_LIST_APPEND(rname->list, rdataset, link); ISC_LIST_APPEND(rname->list, sigrdataset, link); rdataset = NULL; sigrdataset = NULL; cleanup: if (rdataset != NULL) query_putrdataset(client, &rdataset); if (sigrdataset != NULL) query_putrdataset(client, &sigrdataset); } static void query_addwildcardproof(ns_client_t *client, dns_db_t *db, dns_name_t *name, isc_boolean_t ispositive) { isc_buffer_t *dbuf, b; dns_name_t *fname; dns_rdataset_t *rdataset, *sigrdataset; dns_fixedname_t wfixed; dns_name_t *wname; dns_dbnode_t *node; unsigned int options; unsigned int olabels, nlabels; isc_result_t result; dns_rdata_t rdata = DNS_RDATA_INIT; dns_rdata_nsec_t nsec; isc_boolean_t have_wname; int order; CTRACE("query_addwildcardproof"); fname = NULL; rdataset = NULL; sigrdataset = NULL; node = NULL; /* * Get the NOQNAME proof then if !ispositve * get the NOWILDCARD proof. * * DNS_DBFIND_NOWILD finds the NSEC records that covers the * name ignoring any wildcard. From the owner and next names * of this record you can compute which wildcard (if it exists) * will match by finding the longest common suffix of the * owner name and next names with the qname and prefixing that * with the wildcard label. * * e.g. * Given: * example SOA * example NSEC b.example * b.example A * b.example NSEC a.d.example * a.d.example A * a.d.example NSEC g.f.example * g.f.example A * g.f.example NSEC z.i.example * z.i.example A * z.i.example NSEC example * * QNAME: * a.example -> example NSEC b.example * owner common example * next common example * wild *.example * d.b.example -> b.example NSEC a.d.example * owner common b.example * next common example * wild *.b.example * a.f.example -> a.d.example NSEC g.f.example * owner common example * next common f.example * wild *.f.example * j.example -> z.i.example NSEC example * owner common example * next common example * wild *.f.example */ options = client->query.dboptions | DNS_DBFIND_NOWILD; dns_fixedname_init(&wfixed); wname = dns_fixedname_name(&wfixed); again: have_wname = ISC_FALSE; /* * We'll need some resources... */ dbuf = query_getnamebuf(client); if (dbuf == NULL) goto cleanup; fname = query_newname(client, dbuf, &b); rdataset = query_newrdataset(client); sigrdataset = query_newrdataset(client); if (fname == NULL || rdataset == NULL || sigrdataset == NULL) goto cleanup; result = dns_db_find(db, name, NULL, dns_rdatatype_nsec, options, 0, &node, fname, rdataset, sigrdataset); if (node != NULL) dns_db_detachnode(db, &node); if (result == DNS_R_NXDOMAIN) { if (!ispositive) result = dns_rdataset_first(rdataset); if (result == ISC_R_SUCCESS) { dns_rdataset_current(rdataset, &rdata); result = dns_rdata_tostruct(&rdata, &nsec, NULL); } if (result == ISC_R_SUCCESS) { (void)dns_name_fullcompare(name, fname, &order, &olabels); (void)dns_name_fullcompare(name, &nsec.next, &order, &nlabels); if (olabels > nlabels) dns_name_split(name, olabels, NULL, wname); else dns_name_split(name, nlabels, NULL, wname); result = dns_name_concatenate(dns_wildcardname, wname, wname, NULL); if (result == ISC_R_SUCCESS) have_wname = ISC_TRUE; dns_rdata_freestruct(&nsec); } query_addrrset(client, &fname, &rdataset, &sigrdataset, dbuf, DNS_SECTION_AUTHORITY); } if (rdataset != NULL) query_putrdataset(client, &rdataset); if (sigrdataset != NULL) query_putrdataset(client, &sigrdataset); if (fname != NULL) query_releasename(client, &fname); if (have_wname) { ispositive = ISC_TRUE; /* prevent loop */ if (!dns_name_equal(name, wname)) { name = wname; goto again; } } cleanup: if (rdataset != NULL) query_putrdataset(client, &rdataset); if (sigrdataset != NULL) query_putrdataset(client, &sigrdataset); if (fname != NULL) query_releasename(client, &fname); } static void query_addnxrrsetnsec(ns_client_t *client, dns_db_t *db, dns_name_t **namep, dns_rdataset_t **rdatasetp, dns_rdataset_t **sigrdatasetp) { dns_name_t *name; dns_rdataset_t *sigrdataset; dns_rdata_t sigrdata; dns_rdata_rrsig_t sig; unsigned int labels; isc_buffer_t *dbuf, b; dns_name_t *fname; isc_result_t result; name = *namep; if ((name->attributes & DNS_NAMEATTR_WILDCARD) == 0) { query_addrrset(client, namep, rdatasetp, sigrdatasetp, NULL, DNS_SECTION_AUTHORITY); return; } if (sigrdatasetp == NULL) return; sigrdataset = *sigrdatasetp; if (sigrdataset == NULL || !dns_rdataset_isassociated(sigrdataset)) return; result = dns_rdataset_first(sigrdataset); if (result != ISC_R_SUCCESS) return; dns_rdata_init(&sigrdata); dns_rdataset_current(sigrdataset, &sigrdata); result = dns_rdata_tostruct(&sigrdata, &sig, NULL); if (result != ISC_R_SUCCESS) return; labels = dns_name_countlabels(name); if ((unsigned int)sig.labels + 1 >= labels) return; /* XXX */ query_addwildcardproof(client, db, client->query.qname, ISC_TRUE); /* * We'll need some resources... */ dbuf = query_getnamebuf(client); if (dbuf == NULL) return; fname = query_newname(client, dbuf, &b); if (fname == NULL) return; dns_name_split(name, sig.labels + 1, NULL, fname); /* This will succeed, since we've stripped labels. */ RUNTIME_CHECK(dns_name_concatenate(dns_wildcardname, fname, fname, NULL) == ISC_R_SUCCESS); query_addrrset(client, &fname, rdatasetp, sigrdatasetp, dbuf, DNS_SECTION_AUTHORITY); } static void query_resume(isc_task_t *task, isc_event_t *event) { dns_fetchevent_t *devent = (dns_fetchevent_t *)event; ns_client_t *client; isc_boolean_t fetch_cancelled, client_shuttingdown; /* * Resume a query after recursion. */ UNUSED(task); REQUIRE(event->ev_type == DNS_EVENT_FETCHDONE); client = devent->ev_arg; REQUIRE(NS_CLIENT_VALID(client)); REQUIRE(task == client->task); REQUIRE(RECURSING(client)); LOCK(&client->query.fetchlock); if (client->query.fetch != NULL) { /* * This is the fetch we've been waiting for. */ INSIST(devent->fetch == client->query.fetch); client->query.fetch = NULL; fetch_cancelled = ISC_FALSE; /* * Update client->now. */ isc_stdtime_get(&client->now); } else { /* * This is a fetch completion event for a cancelled fetch. * Clean up and don't resume the find. */ fetch_cancelled = ISC_TRUE; } UNLOCK(&client->query.fetchlock); INSIST(client->query.fetch == NULL); client->query.attributes &= ~NS_QUERYATTR_RECURSING; dns_resolver_destroyfetch(&devent->fetch); /* * If this client is shutting down, or this transaction * has timed out, do not resume the find. */ client_shuttingdown = ns_client_shuttingdown(client); if (fetch_cancelled || client_shuttingdown) { if (devent->node != NULL) dns_db_detachnode(devent->db, &devent->node); if (devent->db != NULL) dns_db_detach(&devent->db); query_putrdataset(client, &devent->rdataset); if (devent->sigrdataset != NULL) query_putrdataset(client, &devent->sigrdataset); isc_event_free(&event); if (fetch_cancelled) query_error(client, DNS_R_SERVFAIL); else query_next(client, ISC_R_CANCELED); /* * This may destroy the client. */ ns_client_detach(&client); } else { query_find(client, devent, 0); } } static isc_result_t query_recurse(ns_client_t *client, dns_rdatatype_t qtype, dns_name_t *qdomain, dns_rdataset_t *nameservers) { isc_result_t result; dns_rdataset_t *rdataset, *sigrdataset; inc_stats(client, dns_statscounter_recursion); /* * We are about to recurse, which means that this client will * be unavailable for serving new requests for an indeterminate * amount of time. If this client is currently responsible * for handling incoming queries, set up a new client * object to handle them while we are waiting for a * response. There is no need to replace TCP clients * because those have already been replaced when the * connection was accepted (if allowed by the TCP quota). */ if (client->recursionquota == NULL) { result = isc_quota_attach(&ns_g_server->recursionquota, &client->recursionquota); if (result == ISC_R_SOFTQUOTA) { static isc_stdtime_t last = 0; isc_stdtime_t now; isc_stdtime_get(&now); if (now != last) { last = now; ns_client_log(client, NS_LOGCATEGORY_CLIENT, NS_LOGMODULE_QUERY, ISC_LOG_WARNING, "recursive-clients soft limit " "exceeded, aborting oldest query"); } ns_client_killoldestquery(client); result = ISC_R_SUCCESS; } else if (result == ISC_R_QUOTA) { static isc_stdtime_t last = 0; isc_stdtime_t now; isc_stdtime_get(&now); if (now != last) { last = now; ns_client_log(client, NS_LOGCATEGORY_CLIENT, NS_LOGMODULE_QUERY, ISC_LOG_WARNING, "no more recursive clients: %s", isc_result_totext(result)); } ns_client_killoldestquery(client); } if (result == ISC_R_SUCCESS && !client->mortal && (client->attributes & NS_CLIENTATTR_TCP) == 0) { result = ns_client_replace(client); if (result != ISC_R_SUCCESS) { ns_client_log(client, NS_LOGCATEGORY_CLIENT, NS_LOGMODULE_QUERY, ISC_LOG_WARNING, "ns_client_replace() failed: %s", isc_result_totext(result)); isc_quota_detach(&client->recursionquota); } } if (result != ISC_R_SUCCESS) return (result); ns_client_recursing(client); } /* * Invoke the resolver. */ REQUIRE(nameservers == NULL || nameservers->type == dns_rdatatype_ns); REQUIRE(client->query.fetch == NULL); rdataset = query_newrdataset(client); if (rdataset == NULL) return (ISC_R_NOMEMORY); if (WANTDNSSEC(client)) { sigrdataset = query_newrdataset(client); if (sigrdataset == NULL) { query_putrdataset(client, &rdataset); return (ISC_R_NOMEMORY); } } else sigrdataset = NULL; if (client->query.timerset == ISC_FALSE) ns_client_settimeout(client, 60); result = dns_resolver_createfetch(client->view->resolver, client->query.qname, qtype, qdomain, nameservers, NULL, client->query.fetchoptions, client->task, query_resume, client, rdataset, sigrdataset, &client->query.fetch); if (result == ISC_R_SUCCESS) { /* * Record that we're waiting for an event. A client which * is shutting down will not be destroyed until all the * events have been received. */ } else { query_putrdataset(client, &rdataset); if (sigrdataset != NULL) query_putrdataset(client, &sigrdataset); } return (result); } #define MAX_RESTARTS 16 #define QUERY_ERROR(r) \ do { \ eresult = r; \ want_restart = ISC_FALSE; \ } while (0) /* * Extract a network address from the RDATA of an A or AAAA * record. * * Returns: * ISC_R_SUCCESS * ISC_R_NOTIMPLEMENTED The rdata is not a known address type. */ static isc_result_t rdata_tonetaddr(const dns_rdata_t *rdata, isc_netaddr_t *netaddr) { struct in_addr ina; struct in6_addr in6a; switch (rdata->type) { case dns_rdatatype_a: INSIST(rdata->length == 4); memcpy(&ina.s_addr, rdata->data, 4); isc_netaddr_fromin(netaddr, &ina); return (ISC_R_SUCCESS); case dns_rdatatype_aaaa: INSIST(rdata->length == 16); memcpy(in6a.s6_addr, rdata->data, 16); isc_netaddr_fromin6(netaddr, &in6a); return (ISC_R_SUCCESS); default: return (ISC_R_NOTIMPLEMENTED); } } /* * Find the sort order of 'rdata' in the topology-like * ACL forming the second element in a 2-element top-level * sortlist statement. */ static int query_sortlist_order_2element(const dns_rdata_t *rdata, const void *arg) { isc_netaddr_t netaddr; if (rdata_tonetaddr(rdata, &netaddr) != ISC_R_SUCCESS) return (INT_MAX); return (ns_sortlist_addrorder2(&netaddr, arg)); } /* * Find the sort order of 'rdata' in the matching element * of a 1-element top-level sortlist statement. */ static int query_sortlist_order_1element(const dns_rdata_t *rdata, const void *arg) { isc_netaddr_t netaddr; if (rdata_tonetaddr(rdata, &netaddr) != ISC_R_SUCCESS) return (INT_MAX); return (ns_sortlist_addrorder1(&netaddr, arg)); } /* * Find the sortlist statement that applies to 'client' and set up * the sortlist info in in client->message appropriately. */ static void setup_query_sortlist(ns_client_t *client) { isc_netaddr_t netaddr; dns_rdatasetorderfunc_t order = NULL; const void *order_arg = NULL; isc_netaddr_fromsockaddr(&netaddr, &client->peeraddr); switch (ns_sortlist_setup(client->view->sortlist, &netaddr, &order_arg)) { case NS_SORTLISTTYPE_1ELEMENT: order = query_sortlist_order_1element; break; case NS_SORTLISTTYPE_2ELEMENT: order = query_sortlist_order_2element; break; case NS_SORTLISTTYPE_NONE: order = NULL; break; default: INSIST(0); break; } dns_message_setsortorder(client->message, order, order_arg); } static void query_addnoqnameproof(ns_client_t *client, dns_rdataset_t *rdataset) { isc_buffer_t *dbuf, b; dns_name_t *fname; dns_rdataset_t *nsec, *nsecsig; isc_result_t result = ISC_R_NOMEMORY; CTRACE("query_addnoqnameproof"); fname = NULL; nsec = NULL; nsecsig = NULL; dbuf = query_getnamebuf(client); if (dbuf == NULL) goto cleanup; fname = query_newname(client, dbuf, &b); nsec = query_newrdataset(client); nsecsig = query_newrdataset(client); if (fname == NULL || nsec == NULL || nsecsig == NULL) goto cleanup; result = dns_rdataset_getnoqname(rdataset, fname, nsec, nsecsig); RUNTIME_CHECK(result == ISC_R_SUCCESS); query_addrrset(client, &fname, &nsec, &nsecsig, dbuf, DNS_SECTION_AUTHORITY); cleanup: if (nsec != NULL) query_putrdataset(client, &nsec); if (nsecsig != NULL) query_putrdataset(client, &nsecsig); if (fname != NULL) query_releasename(client, &fname); } static inline void answer_in_glue(ns_client_t *client, dns_rdatatype_t qtype) { dns_name_t *name; dns_message_t *msg; dns_section_t section = DNS_SECTION_ADDITIONAL; dns_rdataset_t *rdataset = NULL; msg = client->message; for (name = ISC_LIST_HEAD(msg->sections[section]); name != NULL; name = ISC_LIST_NEXT(name, link)) if (dns_name_equal(name, client->query.qname)) { for (rdataset = ISC_LIST_HEAD(name->list); rdataset != NULL; rdataset = ISC_LIST_NEXT(rdataset, link)) if (rdataset->type == qtype) break; break; } if (rdataset != NULL) { ISC_LIST_UNLINK(msg->sections[section], name, link); ISC_LIST_PREPEND(msg->sections[section], name, link); ISC_LIST_UNLINK(name->list, rdataset, link); ISC_LIST_PREPEND(name->list, rdataset, link); rdataset->attributes |= DNS_RDATASETATTR_REQUIREDGLUE; } } /* * Do the bulk of query processing for the current query of 'client'. * If 'event' is non-NULL, we are returning from recursion and 'qtype' * is ignored. Otherwise, 'qtype' is the query type. */ static void query_find(ns_client_t *client, dns_fetchevent_t *event, dns_rdatatype_t qtype) { dns_db_t *db, *zdb; dns_dbnode_t *node; dns_rdatatype_t type; dns_name_t *fname, *zfname, *tname, *prefix; dns_rdataset_t *rdataset, *trdataset; dns_rdataset_t *sigrdataset, *zrdataset, *zsigrdataset; dns_rdataset_t **sigrdatasetp; dns_rdata_t rdata = DNS_RDATA_INIT; dns_rdatasetiter_t *rdsiter; isc_boolean_t want_restart, authoritative, is_zone, need_wildcardproof; unsigned int n, nlabels; dns_namereln_t namereln; int order; isc_buffer_t *dbuf; isc_buffer_t b; isc_result_t result, eresult; dns_fixedname_t fixed; dns_fixedname_t wildcardname; dns_dbversion_t *version; dns_zone_t *zone; dns_rdata_cname_t cname; dns_rdata_dname_t dname; unsigned int options; isc_boolean_t empty_wild; dns_rdataset_t *noqname; CTRACE("query_find"); /* * One-time initialization. * * It's especially important to initialize anything that the cleanup * code might cleanup. */ eresult = ISC_R_SUCCESS; fname = NULL; zfname = NULL; rdataset = NULL; zrdataset = NULL; sigrdataset = NULL; zsigrdataset = NULL; node = NULL; db = NULL; zdb = NULL; version = NULL; zone = NULL; need_wildcardproof = ISC_FALSE; empty_wild = ISC_FALSE; options = 0; if (event != NULL) { /* * We're returning from recursion. Restore the query context * and resume. */ want_restart = ISC_FALSE; authoritative = ISC_FALSE; is_zone = ISC_FALSE; qtype = event->qtype; if (qtype == dns_rdatatype_rrsig || qtype == dns_rdatatype_sig) type = dns_rdatatype_any; else type = qtype; db = event->db; node = event->node; rdataset = event->rdataset; sigrdataset = event->sigrdataset; /* * We'll need some resources... */ dbuf = query_getnamebuf(client); if (dbuf == NULL) { QUERY_ERROR(DNS_R_SERVFAIL); goto cleanup; } fname = query_newname(client, dbuf, &b); if (fname == NULL) { QUERY_ERROR(DNS_R_SERVFAIL); goto cleanup; } tname = dns_fixedname_name(&event->foundname); result = dns_name_copy(tname, fname, NULL); if (result != ISC_R_SUCCESS) { QUERY_ERROR(DNS_R_SERVFAIL); goto cleanup; } result = event->result; goto resume; } /* * Not returning from recursion. */ /* * If it's a SIG query, we'll iterate the node. */ if (qtype == dns_rdatatype_rrsig || qtype == dns_rdatatype_sig) type = dns_rdatatype_any; else type = qtype; restart: CTRACE("query_find: restart"); want_restart = ISC_FALSE; authoritative = ISC_FALSE; version = NULL; need_wildcardproof = ISC_FALSE; if (client->view->checknames && !dns_rdata_checkowner(client->query.qname, client->message->rdclass, qtype, ISC_FALSE)) { char namebuf[DNS_NAME_FORMATSIZE]; char typename[DNS_RDATATYPE_FORMATSIZE]; char classname[DNS_RDATACLASS_FORMATSIZE]; dns_name_format(client->query.qname, namebuf, sizeof(namebuf)); dns_rdatatype_format(qtype, typename, sizeof(typename)); dns_rdataclass_format(client->message->rdclass, classname, sizeof(classname)); ns_client_log(client, DNS_LOGCATEGORY_SECURITY, NS_LOGMODULE_QUERY, ISC_LOG_ERROR, "check-names failure %s/%s/%s", namebuf, typename, classname); QUERY_ERROR(DNS_R_REFUSED); goto cleanup; } /* * First we must find the right database. */ options &= DNS_GETDB_NOLOG; /* Preserve DNS_GETDB_NOLOG. */ if (dns_rdatatype_atparent(qtype) && !dns_name_equal(client->query.qname, dns_rootname)) options |= DNS_GETDB_NOEXACT; result = query_getdb(client, client->query.qname, qtype, options, &zone, &db, &version, &is_zone); if ((result != ISC_R_SUCCESS || !is_zone) && !RECURSIONOK(client) && (options & DNS_GETDB_NOEXACT) != 0 && qtype == dns_rdatatype_ds) { /* * Look to see if we are authoritative for the * child zone if the query type is DS. */ dns_db_t *tdb = NULL; dns_zone_t *tzone = NULL; dns_dbversion_t *tversion = NULL; isc_result_t tresult; tresult = query_getzonedb(client, client->query.qname, qtype, DNS_GETDB_PARTIAL, &tzone, &tdb, &tversion); if (tresult == ISC_R_SUCCESS) { options &= ~DNS_GETDB_NOEXACT; query_putrdataset(client, &rdataset); if (db != NULL) dns_db_detach(&db); if (zone != NULL) dns_zone_detach(&zone); version = tversion; db = tdb; zone = tzone; is_zone = ISC_TRUE; result = ISC_R_SUCCESS; } else { if (tdb != NULL) dns_db_detach(&tdb); if (tzone != NULL) dns_zone_detach(&tzone); } } if (result != ISC_R_SUCCESS) { if (result == DNS_R_REFUSED) { if (!PARTIALANSWER(client)) QUERY_ERROR(DNS_R_REFUSED); } else QUERY_ERROR(DNS_R_SERVFAIL); goto cleanup; } if (is_zone) authoritative = ISC_TRUE; if (event == NULL && client->query.restarts == 0) { if (is_zone) { dns_zone_attach(zone, &client->query.authzone); dns_db_attach(db, &client->query.authdb); } client->query.authdbset = ISC_TRUE; } db_find: CTRACE("query_find: db_find"); /* * We'll need some resources... */ dbuf = query_getnamebuf(client); if (dbuf == NULL) { QUERY_ERROR(DNS_R_SERVFAIL); goto cleanup; } fname = query_newname(client, dbuf, &b); rdataset = query_newrdataset(client); if (fname == NULL || rdataset == NULL) { QUERY_ERROR(DNS_R_SERVFAIL); goto cleanup; } if (WANTDNSSEC(client)) { sigrdataset = query_newrdataset(client); if (sigrdataset == NULL) { QUERY_ERROR(DNS_R_SERVFAIL); goto cleanup; } } /* * Now look for an answer in the database. */ result = dns_db_find(db, client->query.qname, version, type, client->query.dboptions, client->now, &node, fname, rdataset, sigrdataset); resume: CTRACE("query_find: resume"); switch (result) { case ISC_R_SUCCESS: /* * This case is handled in the main line below. */ break; case DNS_R_GLUE: case DNS_R_ZONECUT: /* * These cases are handled in the main line below. */ INSIST(is_zone); authoritative = ISC_FALSE; break; case ISC_R_NOTFOUND: /* * The cache doesn't even have the root NS. Get them from * the hints DB. */ INSIST(!is_zone); if (db != NULL) dns_db_detach(&db); if (client->view->hints == NULL) { /* We have no hints. */ result = ISC_R_FAILURE; } else { dns_db_attach(client->view->hints, &db); result = dns_db_find(db, dns_rootname, NULL, dns_rdatatype_ns, 0, client->now, &node, fname, rdataset, sigrdataset); } if (result != ISC_R_SUCCESS) { /* * Nonsensical root hints may require cleanup. */ if (dns_rdataset_isassociated(rdataset)) dns_rdataset_disassociate(rdataset); if (sigrdataset != NULL && dns_rdataset_isassociated(sigrdataset)) dns_rdataset_disassociate(sigrdataset); if (node != NULL) dns_db_detachnode(db, &node); /* * We don't have any root server hints, but * we may have working forwarders, so try to * recurse anyway. */ if (RECURSIONOK(client)) { result = query_recurse(client, qtype, NULL, NULL); if (result == ISC_R_SUCCESS) client->query.attributes |= NS_QUERYATTR_RECURSING; else { /* Unable to recurse. */ QUERY_ERROR(DNS_R_SERVFAIL); } goto cleanup; } else { /* Unable to give root server referral. */ QUERY_ERROR(DNS_R_SERVFAIL); goto cleanup; } } /* * XXXRTH We should trigger root server priming here. */ /* FALLTHROUGH */ case DNS_R_DELEGATION: authoritative = ISC_FALSE; if (is_zone) { /* * Look to see if we are authoritative for the * child zone if the query type is DS. */ if (!RECURSIONOK(client) && (options & DNS_GETDB_NOEXACT) != 0 && qtype == dns_rdatatype_ds) { dns_db_t *tdb = NULL; dns_zone_t *tzone = NULL; dns_dbversion_t *tversion = NULL; result = query_getzonedb(client, client->query.qname, qtype, DNS_GETDB_PARTIAL, &tzone, &tdb, &tversion); if (result == ISC_R_SUCCESS) { options &= ~DNS_GETDB_NOEXACT; query_putrdataset(client, &rdataset); if (sigrdataset != NULL) query_putrdataset(client, &sigrdataset); if (fname != NULL) query_releasename(client, &fname); if (node != NULL) dns_db_detachnode(db, &node); if (db != NULL) dns_db_detach(&db); if (zone != NULL) dns_zone_detach(&zone); version = tversion; db = tdb; zone = tzone; authoritative = ISC_TRUE; goto db_find; } if (tdb != NULL) dns_db_detach(&tdb); if (tzone != NULL) dns_zone_detach(&tzone); } /* * We're authoritative for an ancestor of QNAME. */ if (!USECACHE(client) || !RECURSIONOK(client)) { /* * If we don't have a cache, this is the best * answer. * * If the client is making a nonrecursive * query we always give out the authoritative * delegation. This way even if we get * junk in our cache, we won't fail in our * role as the delegating authority if another * nameserver asks us about a delegated * subzone. * * We enable the retrieval of glue for this * database by setting client->query.gluedb. */ client->query.gluedb = db; client->query.isreferral = ISC_TRUE; /* * We must ensure NOADDITIONAL is off, * because the generation of * additional data is required in * delegations. */ client->query.attributes &= ~NS_QUERYATTR_NOADDITIONAL; if (sigrdataset != NULL) sigrdatasetp = &sigrdataset; else sigrdatasetp = NULL; query_addrrset(client, &fname, &rdataset, sigrdatasetp, dbuf, DNS_SECTION_AUTHORITY); client->query.gluedb = NULL; if (WANTDNSSEC(client) && dns_db_issecure(db)) query_addds(client, db, node); } else { /* * We might have a better answer or delegation * in the cache. We'll remember the current * values of fname, rdataset, and sigrdataset. * We'll then go looking for QNAME in the * cache. If we find something better, we'll * use it instead. */ query_keepname(client, fname, dbuf); zdb = db; zfname = fname; fname = NULL; zrdataset = rdataset; rdataset = NULL; zsigrdataset = sigrdataset; sigrdataset = NULL; dns_db_detachnode(db, &node); version = NULL; db = NULL; dns_db_attach(client->view->cachedb, &db); is_zone = ISC_FALSE; goto db_find; } } else { if (zfname != NULL && !dns_name_issubdomain(fname, zfname)) { /* * We've already got a delegation from * authoritative data, and it is better * than what we found in the cache. Use * it instead of the cache delegation. */ query_releasename(client, &fname); fname = zfname; zfname = NULL; /* * We've already done query_keepname() on * zfname, so we must set dbuf to NULL to * prevent query_addrrset() from trying to * call query_keepname() again. */ dbuf = NULL; query_putrdataset(client, &rdataset); if (sigrdataset != NULL) query_putrdataset(client, &sigrdataset); rdataset = zrdataset; zrdataset = NULL; sigrdataset = zsigrdataset; zsigrdataset = NULL; /* * We don't clean up zdb here because we * may still need it. It will get cleaned * up by the main cleanup code. */ } if (RECURSIONOK(client)) { /* * Recurse! */ if (dns_rdatatype_atparent(type)) result = query_recurse(client, qtype, NULL, NULL); else result = query_recurse(client, qtype, fname, rdataset); if (result == ISC_R_SUCCESS) client->query.attributes |= NS_QUERYATTR_RECURSING; else QUERY_ERROR(DNS_R_SERVFAIL); } else { /* * This is the best answer. */ client->query.attributes |= NS_QUERYATTR_CACHEGLUEOK; client->query.gluedb = zdb; client->query.isreferral = ISC_TRUE; /* * We must ensure NOADDITIONAL is off, * because the generation of * additional data is required in * delegations. */ client->query.attributes &= ~NS_QUERYATTR_NOADDITIONAL; if (sigrdataset != NULL) sigrdatasetp = &sigrdataset; else sigrdatasetp = NULL; query_addrrset(client, &fname, &rdataset, sigrdatasetp, dbuf, DNS_SECTION_AUTHORITY); client->query.gluedb = NULL; client->query.attributes &= ~NS_QUERYATTR_CACHEGLUEOK; if (WANTDNSSEC(client)) query_addds(client, db, node); } } goto cleanup; case DNS_R_EMPTYNAME: result = DNS_R_NXRRSET; /* FALLTHROUGH */ case DNS_R_NXRRSET: INSIST(is_zone); if (dns_rdataset_isassociated(rdataset)) { /* * If we've got a NSEC record, we need to save the * name now because we're going call query_addsoa() * below, and it needs to use the name buffer. */ query_keepname(client, fname, dbuf); } else { /* * We're not going to use fname, and need to release * our hold on the name buffer so query_addsoa() * may use it. */ query_releasename(client, &fname); } /* * Add SOA. */ result = query_addsoa(client, db, ISC_FALSE); if (result != ISC_R_SUCCESS) { QUERY_ERROR(result); goto cleanup; } /* * Add NSEC record if we found one. */ if (WANTDNSSEC(client)) { if (dns_rdataset_isassociated(rdataset)) query_addnxrrsetnsec(client, db, &fname, &rdataset, &sigrdataset); } goto cleanup; case DNS_R_EMPTYWILD: empty_wild = ISC_TRUE; /* FALLTHROUGH */ case DNS_R_NXDOMAIN: INSIST(is_zone); if (dns_rdataset_isassociated(rdataset)) { /* * If we've got a NSEC record, we need to save the * name now because we're going call query_addsoa() * below, and it needs to use the name buffer. */ query_keepname(client, fname, dbuf); } else { /* * We're not going to use fname, and need to release * our hold on the name buffer so query_addsoa() * may use it. */ query_releasename(client, &fname); } /* * Add SOA. If the query was for a SOA record force the * ttl to zero so that it is possible for clients to find * the containing zone of an arbitrary name with a stub * resolver and not have it cached. */ if (qtype == dns_rdatatype_soa) result = query_addsoa(client, db, ISC_TRUE); else result = query_addsoa(client, db, ISC_FALSE); if (result != ISC_R_SUCCESS) { QUERY_ERROR(result); goto cleanup; } /* * Add NSEC record if we found one. */ if (dns_rdataset_isassociated(rdataset)) { if (WANTDNSSEC(client)) { query_addrrset(client, &fname, &rdataset, &sigrdataset, NULL, DNS_SECTION_AUTHORITY); query_addwildcardproof(client, db, client->query.qname, ISC_FALSE); } } /* * Set message rcode. */ if (empty_wild) client->message->rcode = dns_rcode_noerror; else client->message->rcode = dns_rcode_nxdomain; goto cleanup; case DNS_R_NCACHENXDOMAIN: case DNS_R_NCACHENXRRSET: INSIST(!is_zone); authoritative = ISC_FALSE; /* * Set message rcode, if required. */ if (result == DNS_R_NCACHENXDOMAIN) client->message->rcode = dns_rcode_nxdomain; /* * We don't call query_addrrset() because we don't need any * of its extra features (and things would probably break!). */ query_keepname(client, fname, dbuf); dns_message_addname(client->message, fname, DNS_SECTION_AUTHORITY); ISC_LIST_APPEND(fname->list, rdataset, link); fname = NULL; rdataset = NULL; goto cleanup; case DNS_R_CNAME: /* * Keep a copy of the rdataset. We have to do this because * query_addrrset may clear 'rdataset' (to prevent the * cleanup code from cleaning it up). */ trdataset = rdataset; /* * Add the CNAME to the answer section. */ if (sigrdataset != NULL) sigrdatasetp = &sigrdataset; else sigrdatasetp = NULL; if (WANTDNSSEC(client) && (fname->attributes & DNS_NAMEATTR_WILDCARD) != 0) { dns_fixedname_init(&wildcardname); dns_name_copy(fname, dns_fixedname_name(&wildcardname), NULL); need_wildcardproof = ISC_TRUE; } if ((rdataset->attributes & DNS_RDATASETATTR_NOQNAME) != 0 && WANTDNSSEC(client)) noqname = rdataset; else noqname = NULL; query_addrrset(client, &fname, &rdataset, sigrdatasetp, dbuf, DNS_SECTION_ANSWER); if (noqname != NULL) query_addnoqnameproof(client, noqname); /* * We set the PARTIALANSWER attribute so that if anything goes * wrong later on, we'll return what we've got so far. */ client->query.attributes |= NS_QUERYATTR_PARTIALANSWER; /* * Reset qname to be the target name of the CNAME and restart * the query. */ tname = NULL; result = dns_message_gettempname(client->message, &tname); if (result != ISC_R_SUCCESS) goto cleanup; result = dns_rdataset_first(trdataset); if (result != ISC_R_SUCCESS) { dns_message_puttempname(client->message, &tname); goto cleanup; } dns_rdataset_current(trdataset, &rdata); result = dns_rdata_tostruct(&rdata, &cname, NULL); dns_rdata_reset(&rdata); if (result != ISC_R_SUCCESS) { dns_message_puttempname(client->message, &tname); goto cleanup; } dns_name_init(tname, NULL); result = dns_name_dup(&cname.cname, client->mctx, tname); if (result != ISC_R_SUCCESS) { dns_message_puttempname(client->message, &tname); dns_rdata_freestruct(&cname); goto cleanup; } dns_rdata_freestruct(&cname); ns_client_qnamereplace(client, tname); want_restart = ISC_TRUE; if (!WANTRECURSION(client)) options |= DNS_GETDB_NOLOG; goto addauth; case DNS_R_DNAME: /* * Compare the current qname to the found name. We need * to know how many labels and bits are in common because * we're going to have to split qname later on. */ namereln = dns_name_fullcompare(client->query.qname, fname, &order, &nlabels); INSIST(namereln == dns_namereln_subdomain); /* * Keep a copy of the rdataset. We have to do this because * query_addrrset may clear 'rdataset' (to prevent the * cleanup code from cleaning it up). */ trdataset = rdataset; /* * Add the DNAME to the answer section. */ if (sigrdataset != NULL) sigrdatasetp = &sigrdataset; else sigrdatasetp = NULL; if (WANTDNSSEC(client) && (fname->attributes & DNS_NAMEATTR_WILDCARD) != 0) { dns_fixedname_init(&wildcardname); dns_name_copy(fname, dns_fixedname_name(&wildcardname), NULL); need_wildcardproof = ISC_TRUE; } query_addrrset(client, &fname, &rdataset, sigrdatasetp, dbuf, DNS_SECTION_ANSWER); /* * We set the PARTIALANSWER attribute so that if anything goes * wrong later on, we'll return what we've got so far. */ client->query.attributes |= NS_QUERYATTR_PARTIALANSWER; /* * Get the target name of the DNAME. */ tname = NULL; result = dns_message_gettempname(client->message, &tname); if (result != ISC_R_SUCCESS) goto cleanup; result = dns_rdataset_first(trdataset); if (result != ISC_R_SUCCESS) { dns_message_puttempname(client->message, &tname); goto cleanup; } dns_rdataset_current(trdataset, &rdata); result = dns_rdata_tostruct(&rdata, &dname, NULL); dns_rdata_reset(&rdata); if (result != ISC_R_SUCCESS) { dns_message_puttempname(client->message, &tname); goto cleanup; } dns_name_init(tname, NULL); dns_name_clone(&dname.dname, tname); dns_rdata_freestruct(&dname); /* * Construct the new qname. */ dns_fixedname_init(&fixed); prefix = dns_fixedname_name(&fixed); dns_name_split(client->query.qname, nlabels, prefix, NULL); INSIST(fname == NULL); dbuf = query_getnamebuf(client); if (dbuf == NULL) { dns_message_puttempname(client->message, &tname); goto cleanup; } fname = query_newname(client, dbuf, &b); if (fname == NULL) { dns_message_puttempname(client->message, &tname); goto cleanup; } result = dns_name_concatenate(prefix, tname, fname, NULL); if (result != ISC_R_SUCCESS) { dns_message_puttempname(client->message, &tname); if (result == ISC_R_NOSPACE) { /* * RFC 2672, section 4.1, subsection 3c says * we should return YXDOMAIN if the constructed * name would be too long. */ client->message->rcode = dns_rcode_yxdomain; } goto cleanup; } query_keepname(client, fname, dbuf); /* * Synthesize a CNAME for this DNAME. * * We want to synthesize a CNAME since if we don't * then older software that doesn't understand DNAME * will not chain like it should. * * We do not try to synthesize a signature because we hope * that security aware servers will understand DNAME. Also, * even if we had an online key, making a signature * on-the-fly is costly, and not really legitimate anyway * since the synthesized CNAME is NOT in the zone. */ dns_name_init(tname, NULL); (void)query_addcnamelike(client, client->query.qname, fname, trdataset->trust, &tname, dns_rdatatype_cname); if (tname != NULL) dns_message_puttempname(client->message, &tname); /* * Switch to the new qname and restart. */ ns_client_qnamereplace(client, fname); fname = NULL; want_restart = ISC_TRUE; if (!WANTRECURSION(client)) options |= DNS_GETDB_NOLOG; goto addauth; default: /* * Something has gone wrong. */ QUERY_ERROR(DNS_R_SERVFAIL); goto cleanup; } if (WANTDNSSEC(client) && (fname->attributes & DNS_NAMEATTR_WILDCARD) != 0) { dns_fixedname_init(&wildcardname); dns_name_copy(fname, dns_fixedname_name(&wildcardname), NULL); need_wildcardproof = ISC_TRUE; } if (type == dns_rdatatype_any) { /* * XXXRTH Need to handle zonecuts with special case * code. */ n = 0; rdsiter = NULL; result = dns_db_allrdatasets(db, node, version, 0, &rdsiter); if (result != ISC_R_SUCCESS) { QUERY_ERROR(DNS_R_SERVFAIL); goto cleanup; } /* * Calling query_addrrset() with a non-NULL dbuf is going * to either keep or release the name. We don't want it to * release fname, since we may have to call query_addrrset() * more than once. That means we have to call query_keepname() * now, and pass a NULL dbuf to query_addrrset(). * * If we do a query_addrrset() below, we must set fname to * NULL before leaving this block, otherwise we might try to * cleanup fname even though we're using it! */ query_keepname(client, fname, dbuf); tname = fname; result = dns_rdatasetiter_first(rdsiter); while (result == ISC_R_SUCCESS) { dns_rdatasetiter_current(rdsiter, rdataset); if ((qtype == dns_rdatatype_any || rdataset->type == qtype) && rdataset->type != 0) { query_addrrset(client, fname != NULL ? &fname : &tname, &rdataset, NULL, NULL, DNS_SECTION_ANSWER); n++; INSIST(tname != NULL); /* * rdataset is non-NULL only in certain pathological * cases involving DNAMEs. */ if (rdataset != NULL) query_putrdataset(client, &rdataset); rdataset = query_newrdataset(client); if (rdataset == NULL) break; } else { /* * We're not interested in this rdataset. */ dns_rdataset_disassociate(rdataset); } result = dns_rdatasetiter_next(rdsiter); } if (fname != NULL) dns_message_puttempname(client->message, &fname); if (n == 0) { /* * We didn't match any rdatasets. */ if (qtype == dns_rdatatype_rrsig && result == ISC_R_NOMORE) { /* * XXXRTH If this is a secure zone and we * didn't find any SIGs, we should generate * an error unless we were searching for * glue. Ugh. */ /* * We were searching for SIG records in * a nonsecure zone. Send a "no error, * no data" response. */ /* * Add SOA. */ result = query_addsoa(client, db, ISC_FALSE); if (result == ISC_R_SUCCESS) result = ISC_R_NOMORE; } else { /* * Something went wrong. */ result = DNS_R_SERVFAIL; } } dns_rdatasetiter_destroy(&rdsiter); if (result != ISC_R_NOMORE) { QUERY_ERROR(DNS_R_SERVFAIL); goto cleanup; } } else { /* * This is the "normal" case -- an ordinary question to which * we know the answer. */ if (sigrdataset != NULL) sigrdatasetp = &sigrdataset; else sigrdatasetp = NULL; if ((rdataset->attributes & DNS_RDATASETATTR_NOQNAME) != 0 && WANTDNSSEC(client)) noqname = rdataset; else noqname = NULL; query_addrrset(client, &fname, &rdataset, sigrdatasetp, dbuf, DNS_SECTION_ANSWER); if (noqname != NULL) query_addnoqnameproof(client, noqname); /* * We shouldn't ever fail to add 'rdataset' * because it's already in the answer. */ INSIST(rdataset == NULL); } addauth: CTRACE("query_find: addauth"); /* * Add NS records to the authority section (if we haven't already * added them to the answer section). */ if (!want_restart && !NOAUTHORITY(client)) { if (is_zone) { if (!((qtype == dns_rdatatype_ns || qtype == dns_rdatatype_any) && dns_name_equal(client->query.qname, dns_db_origin(db)))) (void)query_addns(client, db); } else if (qtype != dns_rdatatype_ns) { if (fname != NULL) query_releasename(client, &fname); query_addbestns(client); } } /* * Add NSEC records to the authority section if they're needed for * DNSSEC wildcard proofs. */ if (need_wildcardproof && dns_db_issecure(db)) query_addwildcardproof(client, db, dns_fixedname_name(&wildcardname), ISC_TRUE); cleanup: CTRACE("query_find: cleanup"); /* * General cleanup. */ if (rdataset != NULL) query_putrdataset(client, &rdataset); if (sigrdataset != NULL) query_putrdataset(client, &sigrdataset); if (fname != NULL) query_releasename(client, &fname); if (node != NULL) dns_db_detachnode(db, &node); if (db != NULL) dns_db_detach(&db); if (zone != NULL) dns_zone_detach(&zone); if (zdb != NULL) { query_putrdataset(client, &zrdataset); if (zsigrdataset != NULL) query_putrdataset(client, &zsigrdataset); if (zfname != NULL) query_releasename(client, &zfname); dns_db_detach(&zdb); } if (event != NULL) isc_event_free(ISC_EVENT_PTR(&event)); /* * AA bit. */ if (client->query.restarts == 0 && !authoritative) { /* * We're not authoritative, so we must ensure the AA bit * isn't set. */ client->message->flags &= ~DNS_MESSAGEFLAG_AA; } /* * Restart the query? */ if (want_restart && client->query.restarts < MAX_RESTARTS) { client->query.restarts++; goto restart; } if (eresult != ISC_R_SUCCESS && (!PARTIALANSWER(client) || WANTRECURSION(client))) { /* * If we don't have any answer to give the client, * or if the client requested recursion and thus wanted * the complete answer, send an error response. */ query_error(client, eresult); ns_client_detach(&client); } else if (!RECURSING(client)) { /* * We are done. Set up sortlist data for the message * rendering code, make a final tweak to the AA bit if the * auth-nxdomain config option says so, then render and * send the response. */ setup_query_sortlist(client); /* * If this is a referral and the answer to the question * is in the glue sort it to the start of the additional * section. */ if (client->message->counts[DNS_SECTION_ANSWER] == 0 && client->message->rcode == dns_rcode_noerror && (qtype == dns_rdatatype_a || qtype == dns_rdatatype_aaaa)) answer_in_glue(client, qtype); if (client->message->rcode == dns_rcode_nxdomain && client->view->auth_nxdomain == ISC_TRUE) client->message->flags |= DNS_MESSAGEFLAG_AA; query_send(client); ns_client_detach(&client); } CTRACE("query_find: done"); } static inline void log_query(ns_client_t *client) { char namebuf[DNS_NAME_FORMATSIZE]; char typename[DNS_RDATATYPE_FORMATSIZE]; char classname[DNS_RDATACLASS_FORMATSIZE]; dns_rdataset_t *rdataset; int level = ISC_LOG_INFO; if (! isc_log_wouldlog(ns_g_lctx, level)) return; rdataset = ISC_LIST_HEAD(client->query.qname->list); INSIST(rdataset != NULL); dns_name_format(client->query.qname, namebuf, sizeof(namebuf)); dns_rdataclass_format(rdataset->rdclass, classname, sizeof(classname)); dns_rdatatype_format(rdataset->type, typename, sizeof(typename)); ns_client_log(client, NS_LOGCATEGORY_QUERIES, NS_LOGMODULE_QUERY, level, "query: %s %s %s %s%s%s", namebuf, classname, typename, WANTRECURSION(client) ? "+" : "-", (client->signer != NULL) ? "S": "", (client->opt != NULL) ? "E" : ""); } void ns_query_start(ns_client_t *client) { isc_result_t result; dns_message_t *message = client->message; dns_rdataset_t *rdataset; ns_client_t *qclient; dns_rdatatype_t qtype; CTRACE("ns_query_start"); /* * Ensure that appropriate cleanups occur. */ client->next = query_next_callback; /* * Behave as if we don't support DNSSEC if not enabled. */ if (!client->view->enablednssec) { message->flags &= ~DNS_MESSAGEFLAG_CD; client->extflags &= ~DNS_MESSAGEEXTFLAG_DO; } if ((message->flags & DNS_MESSAGEFLAG_RD) != 0) client->query.attributes |= NS_QUERYATTR_WANTRECURSION; if ((client->extflags & DNS_MESSAGEEXTFLAG_DO) != 0) client->attributes |= NS_CLIENTATTR_WANTDNSSEC; if (client->view->minimalresponses) client->query.attributes |= (NS_QUERYATTR_NOAUTHORITY | NS_QUERYATTR_NOADDITIONAL); if ((client->view->cachedb == NULL) || (!client->view->additionalfromcache)) { /* * We don't have a cache. Turn off cache support and * recursion. */ client->query.attributes &= ~(NS_QUERYATTR_RECURSIONOK|NS_QUERYATTR_CACHEOK); } else if ((client->attributes & NS_CLIENTATTR_RA) == 0 || (message->flags & DNS_MESSAGEFLAG_RD) == 0) { /* * If the client isn't allowed to recurse (due to * "recursion no", the allow-recursion ACL, or the * lack of a resolver in this view), or if it * doesn't want recursion, turn recursion off. */ client->query.attributes &= ~NS_QUERYATTR_RECURSIONOK; } /* * Get the question name. */ result = dns_message_firstname(message, DNS_SECTION_QUESTION); if (result != ISC_R_SUCCESS) { query_error(client, result); return; } dns_message_currentname(message, DNS_SECTION_QUESTION, &client->query.qname); client->query.origqname = client->query.qname; result = dns_message_nextname(message, DNS_SECTION_QUESTION); if (result != ISC_R_NOMORE) { if (result == ISC_R_SUCCESS) { /* * There's more than one QNAME in the question * section. */ query_error(client, DNS_R_FORMERR); } else query_error(client, result); return; } if (ns_g_server->log_queries) log_query(client); /* * Check for multiple question queries, since edns1 is dead. */ if (message->counts[DNS_SECTION_QUESTION] > 1) { query_error(client, DNS_R_FORMERR); return; } /* * Check for meta-queries like IXFR and AXFR. */ rdataset = ISC_LIST_HEAD(client->query.qname->list); INSIST(rdataset != NULL); qtype = rdataset->type; if (dns_rdatatype_ismeta(qtype)) { switch (qtype) { case dns_rdatatype_any: break; /* Let query_find handle it. */ case dns_rdatatype_ixfr: case dns_rdatatype_axfr: ns_xfr_start(client, rdataset->type); return; case dns_rdatatype_maila: case dns_rdatatype_mailb: query_error(client, DNS_R_NOTIMP); return; case dns_rdatatype_tkey: result = dns_tkey_processquery(client->message, ns_g_server->tkeyctx, client->view->dynamickeys); if (result == ISC_R_SUCCESS) query_send(client); else query_error(client, result); return; default: /* TSIG, etc. */ query_error(client, DNS_R_FORMERR); return; } } /* * If the client has requested that DNSSEC checking be disabled, * allow lookups to return pending data and instruct the resolver * to return data before validation has completed. */ if (message->flags & DNS_MESSAGEFLAG_CD || qtype == dns_rdatatype_rrsig) { client->query.dboptions |= DNS_DBFIND_PENDINGOK; client->query.fetchoptions |= DNS_FETCHOPT_NOVALIDATE; } /* * Allow glue NS records to be added to the authority section * if the answer is secure. */ if (message->flags & DNS_MESSAGEFLAG_CD) client->query.attributes &= ~NS_QUERYATTR_SECURE; /* * This is an ordinary query. */ result = dns_message_reply(message, ISC_TRUE); if (result != ISC_R_SUCCESS) { query_next(client, result); return; } /* * Assume authoritative response until it is known to be * otherwise. */ message->flags |= DNS_MESSAGEFLAG_AA; /* * Set AD. We must clear it if we add non-validated data to a * response. */ if (client->view->enablednssec) message->flags |= DNS_MESSAGEFLAG_AD; qclient = NULL; ns_client_attach(client, &qclient); query_find(qclient, NULL, qtype); }