diff options
Diffstat (limited to 'lib/ns/query.c')
| -rw-r--r-- | lib/ns/query.c | 12446 |
1 files changed, 12446 insertions, 0 deletions
diff --git a/lib/ns/query.c b/lib/ns/query.c new file mode 100644 index 0000000..00ef955 --- /dev/null +++ b/lib/ns/query.c @@ -0,0 +1,12446 @@ +/* + * Copyright (C) Internet Systems Consortium, Inc. ("ISC") + * + * SPDX-License-Identifier: MPL-2.0 + * + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, you can obtain one at https://mozilla.org/MPL/2.0/. + * + * See the COPYRIGHT file distributed with this work for additional + * information regarding copyright ownership. + */ + +/*! \file */ + +#include <ctype.h> +#include <inttypes.h> +#include <stdbool.h> +#include <string.h> + +#include <isc/hex.h> +#include <isc/mem.h> +#include <isc/once.h> +#include <isc/print.h> +#include <isc/random.h> +#include <isc/result.h> +#include <isc/rwlock.h> +#include <isc/serial.h> +#include <isc/stats.h> +#include <isc/string.h> +#include <isc/thread.h> +#include <isc/util.h> + +#include <dns/adb.h> +#include <dns/badcache.h> +#include <dns/byaddr.h> +#include <dns/cache.h> +#include <dns/db.h> +#include <dns/dlz.h> +#include <dns/dns64.h> +#include <dns/dnsrps.h> +#include <dns/dnssec.h> +#include <dns/events.h> +#include <dns/keytable.h> +#include <dns/message.h> +#include <dns/ncache.h> +#include <dns/nsec.h> +#include <dns/nsec3.h> +#include <dns/order.h> +#include <dns/rbt.h> +#include <dns/rdata.h> +#include <dns/rdataclass.h> +#include <dns/rdatalist.h> +#include <dns/rdataset.h> +#include <dns/rdatasetiter.h> +#include <dns/rdatastruct.h> +#include <dns/rdatatype.h> +#include <dns/resolver.h> +#include <dns/result.h> +#include <dns/stats.h> +#include <dns/tkey.h> +#include <dns/types.h> +#include <dns/view.h> +#include <dns/zone.h> +#include <dns/zt.h> + +#include <ns/client.h> +#include <ns/events.h> +#include <ns/hooks.h> +#include <ns/interfacemgr.h> +#include <ns/log.h> +#include <ns/server.h> +#include <ns/sortlist.h> +#include <ns/stats.h> +#include <ns/xfrout.h> + +#if 0 +/* + * It has been recommended that DNS64 be changed to return excluded + * AAAA addresses if DNS64 synthesis does not occur. This minimises + * the impact on the lookup results. While most DNS AAAA lookups are + * done to send IP packets to a host, not all of them are and filtering + * excluded addresses has a negative impact on those uses. + */ +#define dns64_bis_return_excluded_addresses 1 +#endif /* if 0 */ + +/*% + * Maximum number of chained queries before we give up + * to prevent CNAME loops. + */ +#define MAX_RESTARTS 16 + +#define QUERY_ERROR(qctx, r) \ + do { \ + (qctx)->result = r; \ + (qctx)->want_restart = false; \ + (qctx)->line = __LINE__; \ + } while (0) + +/*% Partial answer? */ +#define PARTIALANSWER(c) \ + (((c)->query.attributes & NS_QUERYATTR_PARTIALANSWER) != 0) +/*% Use Cache? */ +#define USECACHE(c) (((c)->query.attributes & NS_QUERYATTR_CACHEOK) != 0) +/*% Recursion OK? */ +#define RECURSIONOK(c) (((c)->query.attributes & NS_QUERYATTR_RECURSIONOK) != 0) +/*% Recursing? */ +#define RECURSING(c) (((c)->query.attributes & NS_QUERYATTR_RECURSING) != 0) +/*% Want Recursion? */ +#define WANTRECURSION(c) \ + (((c)->query.attributes & NS_QUERYATTR_WANTRECURSION) != 0) +/*% Is TCP? */ +#define TCP(c) (((c)->attributes & NS_CLIENTATTR_TCP) != 0) + +/*% Want DNSSEC? */ +#define WANTDNSSEC(c) (((c)->attributes & NS_CLIENTATTR_WANTDNSSEC) != 0) +/*% Want WANTAD? */ +#define WANTAD(c) (((c)->attributes & NS_CLIENTATTR_WANTAD) != 0) +/*% Client presented a valid COOKIE. */ +#define HAVECOOKIE(c) (((c)->attributes & NS_CLIENTATTR_HAVECOOKIE) != 0) +/*% Client presented a COOKIE. */ +#define WANTCOOKIE(c) (((c)->attributes & NS_CLIENTATTR_WANTCOOKIE) != 0) +/*% Client presented a CLIENT-SUBNET option. */ +#define HAVEECS(c) (((c)->attributes & NS_CLIENTATTR_HAVEECS) != 0) +/*% No authority? */ +#define NOAUTHORITY(c) (((c)->query.attributes & NS_QUERYATTR_NOAUTHORITY) != 0) +/*% No additional? */ +#define NOADDITIONAL(c) \ + (((c)->query.attributes & NS_QUERYATTR_NOADDITIONAL) != 0) +/*% Secure? */ +#define SECURE(c) (((c)->query.attributes & NS_QUERYATTR_SECURE) != 0) +/*% DNS64 A lookup? */ +#define DNS64(c) (((c)->query.attributes & NS_QUERYATTR_DNS64) != 0) + +#define DNS64EXCLUDE(c) \ + (((c)->query.attributes & NS_QUERYATTR_DNS64EXCLUDE) != 0) + +#define REDIRECT(c) (((c)->query.attributes & NS_QUERYATTR_REDIRECT) != 0) + +/*% Was the client already sent a response? */ +#define QUERY_ANSWERED(q) (((q)->attributes & NS_QUERYATTR_ANSWERED) != 0) + +/*% Have we already processed an answer via stale-answer-client-timeout? */ +#define QUERY_STALEPENDING(q) \ + (((q)->attributes & NS_QUERYATTR_STALEPENDING) != 0) + +/*% Does the query allow stale data in the response? */ +#define QUERY_STALEOK(q) (((q)->attributes & NS_QUERYATTR_STALEOK) != 0) + +/*% Does the query wants to check for stale RRset due to a timeout? */ +#define QUERY_STALETIMEOUT(q) (((q)->dboptions & DNS_DBFIND_STALETIMEOUT) != 0) + +/*% Does the rdataset 'r' have an attached 'No QNAME Proof'? */ +#define NOQNAME(r) (((r)->attributes & DNS_RDATASETATTR_NOQNAME) != 0) + +/*% Does the rdataset 'r' contain a stale answer? */ +#define STALE(r) (((r)->attributes & DNS_RDATASETATTR_STALE) != 0) + +/*% Does the rdataset 'r' is stale and within stale-refresh-time? */ +#define STALE_WINDOW(r) (((r)->attributes & DNS_RDATASETATTR_STALE_WINDOW) != 0) + +#ifdef WANT_QUERYTRACE +static void +client_trace(ns_client_t *client, int level, const char *message) { + if (client != NULL && client->query.qname != NULL) { + if (isc_log_wouldlog(ns_lctx, level)) { + char qbuf[DNS_NAME_FORMATSIZE]; + char tbuf[DNS_RDATATYPE_FORMATSIZE]; + dns_name_format(client->query.qname, qbuf, + sizeof(qbuf)); + dns_rdatatype_format(client->query.qtype, tbuf, + sizeof(tbuf)); + isc_log_write(ns_lctx, NS_LOGCATEGORY_CLIENT, + NS_LOGMODULE_QUERY, level, + "query client=%p thread=0x%" PRIxPTR + "(%s/%s): %s", + client, isc_thread_self(), qbuf, tbuf, + message); + } + } else { + isc_log_write(ns_lctx, NS_LOGCATEGORY_CLIENT, + NS_LOGMODULE_QUERY, level, + "query client=%p thread=0x%" PRIxPTR + "(<unknown-query>): %s", + client, isc_thread_self(), message); + } +} +#define CTRACE(l, m) client_trace(client, l, m) +#define CCTRACE(l, m) client_trace(qctx->client, l, m) +#else /* ifdef WANT_QUERYTRACE */ +#define CTRACE(l, m) ((void)m) +#define CCTRACE(l, m) ((void)m) +#endif /* WANT_QUERYTRACE */ + +#define DNS_GETDB_NOEXACT 0x01U +#define DNS_GETDB_NOLOG 0x02U +#define DNS_GETDB_PARTIAL 0x04U +#define DNS_GETDB_IGNOREACL 0x08U +#define DNS_GETDB_STALEFIRST 0X0CU + +#define PENDINGOK(x) (((x)&DNS_DBFIND_PENDINGOK) != 0) + +#define SFCACHE_CDFLAG 0x1 + +/* + * SAVE and RESTORE have the same semantics as: + * + * foo_attach(b, &a); + * foo_detach(&b); + * + * without the locking and magic testing. + * + * We use the names SAVE and RESTORE to show the operation being performed, + * even though the two macros are identical. + */ +#define SAVE(a, b) \ + do { \ + INSIST(a == NULL); \ + a = b; \ + b = NULL; \ + } while (0) +#define RESTORE(a, b) SAVE(a, b) + +static bool +validate(ns_client_t *client, dns_db_t *db, dns_name_t *name, + dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset); + +static void +query_findclosestnsec3(dns_name_t *qname, dns_db_t *db, + dns_dbversion_t *version, ns_client_t *client, + dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset, + dns_name_t *fname, bool exact, dns_name_t *found); + +static void +log_queryerror(ns_client_t *client, isc_result_t result, int line, int level); + +static void +rpz_st_clear(ns_client_t *client); + +static bool +rpz_ck_dnssec(ns_client_t *client, isc_result_t qresult, + dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset); + +static void +log_noexistnodata(void *val, int level, const char *fmt, ...) + ISC_FORMAT_PRINTF(3, 4); + +static isc_result_t +query_addanswer(query_ctx_t *qctx); + +static isc_result_t +query_prepare_delegation_response(query_ctx_t *qctx); + +/* + * Return the hooktable in use with 'qctx', or if there isn't one + * set, return the default hooktable. + */ +static ns_hooktable_t * +get_hooktab(query_ctx_t *qctx) { + if (qctx == NULL || qctx->view == NULL || qctx->view->hooktable == NULL) + { + return (ns__hook_table); + } + + return (qctx->view->hooktable); +} + +/* + * Call the specified hook function in every configured module that implements + * that function. If any hook function returns NS_HOOK_RETURN, we + * set 'result' and terminate processing by jumping to the 'cleanup' tag. + * + * (Note that a hook function may set the 'result' to ISC_R_SUCCESS but + * still terminate processing within the calling function. That's why this + * is a macro instead of a static function; it needs to be able to use + * 'goto cleanup' regardless of the return value.) + */ +#define CALL_HOOK(_id, _qctx) \ + do { \ + isc_result_t _res = result; \ + ns_hooktable_t *_tab = get_hooktab(_qctx); \ + ns_hook_t *_hook; \ + _hook = ISC_LIST_HEAD((*_tab)[_id]); \ + while (_hook != NULL) { \ + ns_hook_action_t _func = _hook->action; \ + void *_data = _hook->action_data; \ + INSIST(_func != NULL); \ + switch (_func(_qctx, _data, &_res)) { \ + case NS_HOOK_CONTINUE: \ + _hook = ISC_LIST_NEXT(_hook, link); \ + break; \ + case NS_HOOK_RETURN: \ + result = _res; \ + goto cleanup; \ + default: \ + UNREACHABLE(); \ + } \ + } \ + } while (false) + +/* + * Call the specified hook function in every configured module that + * implements that function. All modules are called; hook function return + * codes are ignored. This is intended for use with initialization and + * destruction calls which *must* run in every configured module. + * + * (This could be implemented as a static void function, but is left as a + * macro for symmetry with CALL_HOOK above.) + */ +#define CALL_HOOK_NORETURN(_id, _qctx) \ + do { \ + isc_result_t _res; \ + ns_hooktable_t *_tab = get_hooktab(_qctx); \ + ns_hook_t *_hook; \ + _hook = ISC_LIST_HEAD((*_tab)[_id]); \ + while (_hook != NULL) { \ + ns_hook_action_t _func = _hook->action; \ + void *_data = _hook->action_data; \ + INSIST(_func != NULL); \ + _func(_qctx, _data, &_res); \ + _hook = ISC_LIST_NEXT(_hook, link); \ + } \ + } while (false) + +/* + * The functions defined below implement the query logic that previously lived + * in the single very complex function query_find(). The query_ctx_t structure + * defined in <ns/query.h> maintains state from function to function. The call + * flow for the general query processing algorithm is described below: + * + * 1. Set up query context and other resources for a client + * query (query_setup()) + * + * 2. Start the search (ns__query_start()) + * + * 3. Identify authoritative data sources which may have an answer; + * search them (query_lookup()). If an answer is found, go to 7. + * + * 4. If recursion or cache access are allowed, search the cache + * (query_lookup() again, using the cache database) to find a better + * answer. If an answer is found, go to 7. + * + * 5. If recursion is allowed, begin recursion (ns_query_recurse()). + * Go to 15 to clean up this phase of the query. When recursion + * is complete, processing will resume at 6. + * + * 6. Resume from recursion; set up query context for resumed processing. + * + * 7. Determine what sort of answer we've found (query_gotanswer()) + * and call other functions accordingly: + * - not found (auth or cache), go to 8 + * - delegation, go to 9 + * - no such domain (auth), go to 10 + * - empty answer (auth), go to 11 + * - negative response (cache), go to 12 + * - answer found, go to 13 + * + * 8. The answer was not found in the database (query_notfound(). + * Set up a referral and go to 9. + * + * 9. Handle a delegation response (query_delegation()). If we need + * to and are allowed to recurse (query_delegation_recurse()), go to 5, + * otherwise go to 15 to clean up and return the delegation to the client. + * + * 10. No such domain (query_nxdomain()). Attempt redirection; if + * unsuccessful, add authority section records (query_addsoa(), + * query_addauth()), then go to 15 to return NXDOMAIN to client. + * + * 11. Empty answer (query_nodata()). Add authority section records + * (query_addsoa(), query_addauth()) and signatures if authoritative + * (query_sign_nodata()) then go to 15 and return + * NOERROR/ANCOUNT=0 to client. + * + * 12. No such domain or empty answer returned from cache (query_ncache()). + * Set response code appropriately, go to 11. + * + * 13. Prepare a response (query_prepresponse()) and then fill it + * appropriately (query_respond(), or for type ANY, + * query_respond_any()). + * + * 14. If a restart is needed due to CNAME/DNAME chaining, go to 2. + * + * 15. Clean up resources. If recursing, stop and wait for the event + * handler to be called back (step 6). If an answer is ready, + * return it to the client. + * + * (XXX: This description omits several special cases including + * DNS64, RPZ, RRL, and the SERVFAIL cache. It also doesn't discuss + * plugins.) + */ + +static void +query_trace(query_ctx_t *qctx); + +static void +qctx_init(ns_client_t *client, dns_fetchevent_t **eventp, dns_rdatatype_t qtype, + query_ctx_t *qctx); + +static isc_result_t +query_setup(ns_client_t *client, dns_rdatatype_t qtype); + +static isc_result_t +query_lookup(query_ctx_t *qctx); + +static void +fetch_callback(isc_task_t *task, isc_event_t *event); + +static void +recparam_update(ns_query_recparam_t *param, dns_rdatatype_t qtype, + const dns_name_t *qname, const dns_name_t *qdomain); + +static isc_result_t +query_resume(query_ctx_t *qctx); + +static isc_result_t +query_checkrrl(query_ctx_t *qctx, isc_result_t result); + +static isc_result_t +query_checkrpz(query_ctx_t *qctx, isc_result_t result); + +static isc_result_t +query_rpzcname(query_ctx_t *qctx, dns_name_t *cname); + +static isc_result_t +query_gotanswer(query_ctx_t *qctx, isc_result_t result); + +static void +query_addnoqnameproof(query_ctx_t *qctx); + +static isc_result_t +query_respond_any(query_ctx_t *qctx); + +static isc_result_t +query_respond(query_ctx_t *qctx); + +static isc_result_t +query_dns64(query_ctx_t *qctx); + +static void +query_filter64(query_ctx_t *qctx); + +static isc_result_t +query_notfound(query_ctx_t *qctx); + +static isc_result_t +query_zone_delegation(query_ctx_t *qctx); + +static isc_result_t +query_delegation(query_ctx_t *qctx); + +static isc_result_t +query_delegation_recurse(query_ctx_t *qctx); + +static void +query_addds(query_ctx_t *qctx); + +static isc_result_t +query_nodata(query_ctx_t *qctx, isc_result_t result); + +static isc_result_t +query_sign_nodata(query_ctx_t *qctx); + +static void +query_addnxrrsetnsec(query_ctx_t *qctx); + +static isc_result_t +query_nxdomain(query_ctx_t *qctx, isc_result_t res); + +static isc_result_t +query_redirect(query_ctx_t *qctx); + +static isc_result_t +query_ncache(query_ctx_t *qctx, isc_result_t result); + +static isc_result_t +query_coveringnsec(query_ctx_t *qctx); + +static isc_result_t +query_zerottl_refetch(query_ctx_t *qctx); + +static isc_result_t +query_cname(query_ctx_t *qctx); + +static isc_result_t +query_dname(query_ctx_t *qctx); + +static isc_result_t +query_addcname(query_ctx_t *qctx, dns_trust_t trust, dns_ttl_t ttl); + +static isc_result_t +query_prepresponse(query_ctx_t *qctx); + +static isc_result_t +query_addsoa(query_ctx_t *qctx, unsigned int override_ttl, + dns_section_t section); + +static isc_result_t +query_addns(query_ctx_t *qctx); + +static void +query_addbestns(query_ctx_t *qctx); + +static void +query_addwildcardproof(query_ctx_t *qctx, bool ispositive, bool nodata); + +static void +query_addauth(query_ctx_t *qctx); + +static void +query_clear_stale(ns_client_t *client); + +/* + * Increment query statistics counters. + */ +static void +inc_stats(ns_client_t *client, isc_statscounter_t counter) { + dns_zone_t *zone = client->query.authzone; + dns_rdatatype_t qtype; + dns_rdataset_t *rdataset; + isc_stats_t *zonestats; + dns_stats_t *querystats = NULL; + + ns_stats_increment(client->sctx->nsstats, counter); + + if (zone == NULL) { + return; + } + + /* Do regular response type stats */ + zonestats = dns_zone_getrequeststats(zone); + + if (zonestats != NULL) { + isc_stats_increment(zonestats, counter); + } + + /* Do query type statistics + * + * We only increment per-type if we're using the authoritative + * answer counter, preventing double-counting. + */ + if (counter == ns_statscounter_authans) { + querystats = dns_zone_getrcvquerystats(zone); + if (querystats != NULL) { + rdataset = ISC_LIST_HEAD(client->query.qname->list); + if (rdataset != NULL) { + qtype = rdataset->type; + dns_rdatatypestats_increment(querystats, qtype); + } + } + } +} + +static void +query_send(ns_client_t *client) { + isc_statscounter_t counter; + + if ((client->message->flags & DNS_MESSAGEFLAG_AA) == 0) { + inc_stats(client, ns_statscounter_nonauthans); + } else { + inc_stats(client, ns_statscounter_authans); + } + + if (client->message->rcode == dns_rcode_noerror) { + dns_section_t answer = DNS_SECTION_ANSWER; + if (ISC_LIST_EMPTY(client->message->sections[answer])) { + if (client->query.isreferral) { + counter = ns_statscounter_referral; + } else { + counter = ns_statscounter_nxrrset; + } + } else { + counter = ns_statscounter_success; + } + } else if (client->message->rcode == dns_rcode_nxdomain) { + counter = ns_statscounter_nxdomain; + } else if (client->message->rcode == dns_rcode_badcookie) { + counter = ns_statscounter_badcookie; + } else { /* We end up here in case of YXDOMAIN, and maybe others */ + counter = ns_statscounter_failure; + } + + inc_stats(client, counter); + ns_client_send(client); + + if (!client->nodetach) { + isc_nmhandle_detach(&client->reqhandle); + } +} + +static void +query_error(ns_client_t *client, isc_result_t result, int line) { + int loglevel = ISC_LOG_DEBUG(3); + + switch (dns_result_torcode(result)) { + case dns_rcode_servfail: + loglevel = ISC_LOG_DEBUG(1); + inc_stats(client, ns_statscounter_servfail); + break; + case dns_rcode_formerr: + inc_stats(client, ns_statscounter_formerr); + break; + default: + inc_stats(client, ns_statscounter_failure); + break; + } + + if ((client->sctx->options & NS_SERVER_LOGQUERIES) != 0) { + loglevel = ISC_LOG_INFO; + } + + log_queryerror(client, result, line, loglevel); + + ns_client_error(client, result); + + if (!client->nodetach) { + isc_nmhandle_detach(&client->reqhandle); + } +} + +static void +query_next(ns_client_t *client, isc_result_t result) { + if (result == DNS_R_DUPLICATE) { + inc_stats(client, ns_statscounter_duplicate); + } else if (result == DNS_R_DROP) { + inc_stats(client, ns_statscounter_dropped); + } else { + inc_stats(client, ns_statscounter_failure); + } + ns_client_drop(client, result); + + if (!client->nodetach) { + isc_nmhandle_detach(&client->reqhandle); + } +} + +static void +query_freefreeversions(ns_client_t *client, bool 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) { + REQUIRE(NS_CLIENT_VALID(client)); + + LOCK(&client->query.fetchlock); + if (client->query.fetch != NULL) { + dns_resolver_cancelfetch(client->query.fetch); + + client->query.fetch = NULL; + } + if (client->query.hookactx != NULL) { + client->query.hookactx->cancel(client->query.hookactx); + client->query.hookactx = NULL; + } + UNLOCK(&client->query.fetchlock); +} + +static void +query_reset(ns_client_t *client, bool everything) { + isc_buffer_t *dbuf, *dbuf_next; + ns_dbversion_t *dbversion, *dbversion_next; + + CTRACE(ISC_LOG_DEBUG(3), "query_reset"); + + /*% + * 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, 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); + } + + if (client->query.dns64_aaaa != NULL) { + ns_client_putrdataset(client, &client->query.dns64_aaaa); + } + if (client->query.dns64_sigaaaa != NULL) { + ns_client_putrdataset(client, &client->query.dns64_sigaaaa); + } + if (client->query.dns64_aaaaok != NULL) { + isc_mem_put(client->mctx, client->query.dns64_aaaaok, + client->query.dns64_aaaaoklen * sizeof(bool)); + client->query.dns64_aaaaok = NULL; + client->query.dns64_aaaaoklen = 0; + } + + ns_client_putrdataset(client, &client->query.redirect.rdataset); + ns_client_putrdataset(client, &client->query.redirect.sigrdataset); + if (client->query.redirect.db != NULL) { + if (client->query.redirect.node != NULL) { + dns_db_detachnode(client->query.redirect.db, + &client->query.redirect.node); + } + dns_db_detach(&client->query.redirect.db); + } + if (client->query.redirect.zone != NULL) { + dns_zone_detach(&client->query.redirect.zone); + } + + 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 = false; + if (client->query.rpz_st != NULL) { + rpz_st_clear(client); + if (everything) { + INSIST(client->query.rpz_st->rpsdb == NULL); + isc_mem_put(client->mctx, client->query.rpz_st, + sizeof(*client->query.rpz_st)); + client->query.rpz_st = NULL; + } + } + client->query.origqname = NULL; + client->query.dboptions = 0; + client->query.fetchoptions = 0; + client->query.gluedb = NULL; + client->query.authdbset = false; + client->query.isreferral = false; + client->query.dns64_options = 0; + client->query.dns64_ttl = UINT32_MAX; + recparam_update(&client->query.recparam, 0, NULL, NULL); + client->query.root_key_sentinel_keyid = 0; + client->query.root_key_sentinel_is_ta = false; + client->query.root_key_sentinel_not_ta = false; +} + +static void +query_cleanup(ns_client_t *client) { + query_reset(client, false); +} + +void +ns_query_free(ns_client_t *client) { + REQUIRE(NS_CLIENT_VALID(client)); + + query_reset(client, true); +} + +isc_result_t +ns_query_init(ns_client_t *client) { + isc_result_t result = ISC_R_SUCCESS; + + REQUIRE(NS_CLIENT_VALID(client)); + + 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 = false; + client->query.rpz_st = NULL; + client->query.qname = NULL; + /* + * This mutex is destroyed when the client is destroyed in + * exit_check(). + */ + isc_mutex_init(&client->query.fetchlock); + + client->query.fetch = NULL; + client->query.prefetch = NULL; + client->query.authdb = NULL; + client->query.authzone = NULL; + client->query.authdbset = false; + client->query.isreferral = false; + client->query.dns64_aaaa = NULL; + client->query.dns64_sigaaaa = NULL; + client->query.dns64_aaaaok = NULL; + client->query.dns64_aaaaoklen = 0; + client->query.redirect.db = NULL; + client->query.redirect.node = NULL; + client->query.redirect.zone = NULL; + client->query.redirect.qtype = dns_rdatatype_none; + client->query.redirect.result = ISC_R_SUCCESS; + client->query.redirect.rdataset = NULL; + client->query.redirect.sigrdataset = NULL; + client->query.redirect.authoritative = false; + client->query.redirect.is_zone = false; + client->query.redirect.fname = + dns_fixedname_initname(&client->query.redirect.fixed); + query_reset(client, false); + ns_client_newdbversion(client, 3); + ns_client_newnamebuf(client); + + return (result); +} + +/*% + * Check if 'client' is allowed to query the cache of its associated view. + * Unless 'options' has DNS_GETDB_NOLOG set, log the result of cache ACL + * evaluation using the appropriate level, along with 'name' and 'qtype'. + * + * The cache ACL is only evaluated once for each client and then the result is + * cached: if NS_QUERYATTR_CACHEACLOKVALID is set in client->query.attributes, + * cache ACL evaluation has already been performed. The evaluation result is + * also stored in client->query.attributes: if NS_QUERYATTR_CACHEACLOK is set, + * the client is allowed cache access. + * + * Returns: + * + *\li #ISC_R_SUCCESS 'client' is allowed to access cache + *\li #DNS_R_REFUSED 'client' is not allowed to access cache + */ +static isc_result_t +query_checkcacheaccess(ns_client_t *client, const dns_name_t *name, + dns_rdatatype_t qtype, unsigned int options) { + isc_result_t result; + + if ((client->query.attributes & NS_QUERYATTR_CACHEACLOKVALID) == 0) { + enum refusal_reasons { + ALLOW_QUERY_CACHE, + ALLOW_QUERY_CACHE_ON + }; + static const char *acl_desc[] = { + "allow-query-cache did not match", + "allow-query-cache-on did not match", + }; + + /* + * The view's cache ACLs have not yet been evaluated. + * Do it now. Both allow-query-cache and + * allow-query-cache-on must be satisfied. + */ + bool log = ((options & DNS_GETDB_NOLOG) == 0); + char msg[NS_CLIENT_ACLMSGSIZE("query (cache)")]; + + enum refusal_reasons refusal_reason = ALLOW_QUERY_CACHE; + result = ns_client_checkaclsilent(client, NULL, + client->view->cacheacl, true); + if (result == ISC_R_SUCCESS) { + refusal_reason = ALLOW_QUERY_CACHE_ON; + result = ns_client_checkaclsilent( + client, &client->destaddr, + client->view->cacheonacl, true); + } + if (result == ISC_R_SUCCESS) { + /* + * We were allowed by the "allow-query-cache" ACL. + */ + client->query.attributes |= NS_QUERYATTR_CACHEACLOK; + if (log && isc_log_wouldlog(ns_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 { + /* + * We were denied by the "allow-query-cache" ACL. + * There is no need to clear NS_QUERYATTR_CACHEACLOK + * since it is cleared by query_reset(), before query + * processing starts. + */ + ns_client_extendederror(client, DNS_EDE_PROHIBITED, + NULL); + + 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 (%s)", msg, + acl_desc[refusal_reason]); + } + } + + /* + * Evaluation has been finished; make sure we will just consult + * NS_QUERYATTR_CACHEACLOK for this client from now on. + */ + client->query.attributes |= NS_QUERYATTR_CACHEACLOKVALID; + } + + return ((client->query.attributes & NS_QUERYATTR_CACHEACLOK) != 0 + ? ISC_R_SUCCESS + : DNS_R_REFUSED); +} + +static isc_result_t +query_validatezonedb(ns_client_t *client, const dns_name_t *name, + dns_rdatatype_t qtype, unsigned int options, + dns_zone_t *zone, dns_db_t *db, + dns_dbversion_t **versionp) { + isc_result_t result; + dns_acl_t *queryacl, *queryonacl; + ns_dbversion_t *dbversion; + + REQUIRE(zone != NULL); + REQUIRE(db != NULL); + + /* + * Mirror zone data is treated as cache data. + */ + if (dns_zone_gettype(zone) == dns_zone_mirror) { + return (query_checkcacheaccess(client, name, qtype, options)); + } + + /* + * 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. This does not apply if we're + * answering a query where recursion is requested and allowed. + */ + if (client->query.rpz_st == NULL && + !(WANTRECURSION(client) && RECURSIONOK(client)) && + client->query.authdbset && db != client->query.authdb) + { + return (DNS_R_REFUSED); + } + + /* + * Non recursive query to a static-stub zone is prohibited; its + * zone content is not public data, but a part of local configuration + * and should not be disclosed. + */ + if (dns_zone_gettype(zone) == dns_zone_staticstub && + !RECURSIONOK(client)) + { + return (DNS_R_REFUSED); + } + + /* + * 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. + */ + + /* + * Get the current version of this database. + */ + dbversion = ns_client_findversion(client, db); + if (dbversion == NULL) { + CTRACE(ISC_LOG_ERROR, "unable to get db version"); + return (DNS_R_SERVFAIL); + } + + if ((options & DNS_GETDB_IGNOREACL) != 0) { + goto approved; + } + if (dbversion->acl_checked) { + if (!dbversion->queryok) { + return (DNS_R_REFUSED); + } + goto approved; + } + + 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. + */ + dbversion->acl_checked = true; + if ((client->query.attributes & NS_QUERYATTR_QUERYOK) == + 0) + { + dbversion->queryok = false; + return (DNS_R_REFUSED); + } + dbversion->queryok = true; + goto approved; + } + } + + result = ns_client_checkaclsilent(client, NULL, queryacl, true); + if ((options & DNS_GETDB_NOLOG) == 0) { + char msg[NS_CLIENT_ACLMSGSIZE("query")]; + if (result == ISC_R_SUCCESS) { + if (isc_log_wouldlog(ns_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); + ns_client_extendederror(client, DNS_EDE_PROHIBITED, + NULL); + } + } + + 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 and only if we've gotten this far, check allow-query-on too */ + if (result == ISC_R_SUCCESS) { + queryonacl = dns_zone_getqueryonacl(zone); + if (queryonacl == NULL) { + queryonacl = client->view->queryonacl; + } + + result = ns_client_checkaclsilent(client, &client->destaddr, + queryonacl, true); + if (result != ISC_R_SUCCESS) { + ns_client_extendederror(client, DNS_EDE_PROHIBITED, + NULL); + } + if ((options & DNS_GETDB_NOLOG) == 0 && result != ISC_R_SUCCESS) + { + ns_client_log(client, DNS_LOGCATEGORY_SECURITY, + NS_LOGMODULE_QUERY, ISC_LOG_INFO, + "query-on denied"); + } + } + + dbversion->acl_checked = true; + if (result != ISC_R_SUCCESS) { + dbversion->queryok = false; + return (DNS_R_REFUSED); + } + dbversion->queryok = true; + +approved: + /* Transfer ownership, if necessary. */ + if (versionp != NULL) { + *versionp = dbversion->version; + } + return (ISC_R_SUCCESS); +} + +static isc_result_t +query_getzonedb(ns_client_t *client, const 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; + unsigned int ztoptions; + dns_zone_t *zone = NULL; + dns_db_t *db = NULL; + bool partial = false; + + REQUIRE(zonep != NULL && *zonep == NULL); + REQUIRE(dbp != NULL && *dbp == NULL); + + /*% + * Find a zone database to answer the query. + */ + ztoptions = DNS_ZTFIND_MIRROR; + if ((options & DNS_GETDB_NOEXACT) != 0) { + ztoptions |= DNS_ZTFIND_NOEXACT; + } + + result = dns_zt_find(client->view->zonetable, name, ztoptions, NULL, + &zone); + + if (result == DNS_R_PARTIALMATCH) { + partial = true; + } + if (result == ISC_R_SUCCESS || result == DNS_R_PARTIALMATCH) { + result = dns_zone_getdb(zone, &db); + } + + if (result != ISC_R_SUCCESS) { + goto fail; + } + + result = query_validatezonedb(client, name, qtype, options, zone, db, + versionp); + + if (result != ISC_R_SUCCESS) { + goto fail; + } + + /* Transfer ownership. */ + *zonep = zone; + *dbp = db; + + if (partial && (options & DNS_GETDB_PARTIAL) != 0) { + return (DNS_R_PARTIALMATCH); + } + return (ISC_R_SUCCESS); + +fail: + if (zone != NULL) { + dns_zone_detach(&zone); + } + if (db != NULL) { + dns_db_detach(&db); + } + + return (result); +} + +static void +rpz_log_rewrite(ns_client_t *client, bool disabled, dns_rpz_policy_t policy, + dns_rpz_type_t type, dns_zone_t *p_zone, dns_name_t *p_name, + dns_name_t *cname, dns_rpz_num_t rpz_num) { + char cname_buf[DNS_NAME_FORMATSIZE] = { 0 }; + char p_name_buf[DNS_NAME_FORMATSIZE]; + char qname_buf[DNS_NAME_FORMATSIZE]; + char classbuf[DNS_RDATACLASS_FORMATSIZE]; + char typebuf[DNS_RDATATYPE_FORMATSIZE]; + const char *s1 = cname_buf, *s2 = cname_buf; + dns_rdataset_t *rdataset; + dns_rpz_st_t *st; + isc_stats_t *zonestats; + + /* + * Count enabled rewrites in the global counter. + * Count both enabled and disabled rewrites for each zone. + */ + if (!disabled && policy != DNS_RPZ_POLICY_PASSTHRU) { + ns_stats_increment(client->sctx->nsstats, + ns_statscounter_rpz_rewrites); + } + if (p_zone != NULL) { + zonestats = dns_zone_getrequeststats(p_zone); + if (zonestats != NULL) { + isc_stats_increment(zonestats, + ns_statscounter_rpz_rewrites); + } + } + + if (!isc_log_wouldlog(ns_lctx, DNS_RPZ_INFO_LEVEL)) { + return; + } + + st = client->query.rpz_st; + if ((st->popt.no_log & DNS_RPZ_ZBIT(rpz_num)) != 0) { + return; + } + + dns_name_format(client->query.qname, qname_buf, sizeof(qname_buf)); + dns_name_format(p_name, p_name_buf, sizeof(p_name_buf)); + if (cname != NULL) { + s1 = " (CNAME to: "; + dns_name_format(cname, cname_buf, sizeof(cname_buf)); + s2 = ")"; + } + + /* + * Log Qclass and Qtype in addition to existing + * fields. + */ + rdataset = ISC_LIST_HEAD(client->query.origqname->list); + INSIST(rdataset != NULL); + dns_rdataclass_format(rdataset->rdclass, classbuf, sizeof(classbuf)); + dns_rdatatype_format(rdataset->type, typebuf, sizeof(typebuf)); + + /* It's possible to have a separate log channel for rpz passthru. */ + isc_logcategory_t *log_cat = (policy == DNS_RPZ_POLICY_PASSTHRU) + ? DNS_LOGCATEGORY_RPZ_PASSTHRU + : DNS_LOGCATEGORY_RPZ; + + ns_client_log(client, log_cat, NS_LOGMODULE_QUERY, DNS_RPZ_INFO_LEVEL, + "%srpz %s %s rewrite %s/%s/%s via %s%s%s%s", + disabled ? "disabled " : "", dns_rpz_type2str(type), + dns_rpz_policy2str(policy), qname_buf, typebuf, classbuf, + p_name_buf, s1, cname_buf, s2); +} + +static void +rpz_log_fail_helper(ns_client_t *client, int level, dns_name_t *p_name, + dns_rpz_type_t rpz_type1, dns_rpz_type_t rpz_type2, + const char *str, isc_result_t result) { + char qnamebuf[DNS_NAME_FORMATSIZE]; + char p_namebuf[DNS_NAME_FORMATSIZE]; + const char *failed, *via, *slash, *str_blank; + const char *rpztypestr1; + const char *rpztypestr2; + + if (!isc_log_wouldlog(ns_lctx, level)) { + return; + } + + /* + * bin/tests/system/rpz/tests.sh looks for "rpz.*failed" for problems. + */ + if (level <= DNS_RPZ_DEBUG_LEVEL1) { + failed = " failed: "; + } else { + failed = ": "; + } + + rpztypestr1 = dns_rpz_type2str(rpz_type1); + if (rpz_type2 != DNS_RPZ_TYPE_BAD) { + slash = "/"; + rpztypestr2 = dns_rpz_type2str(rpz_type2); + } else { + slash = ""; + rpztypestr2 = ""; + } + + str_blank = (*str != ' ' && *str != '\0') ? " " : ""; + + dns_name_format(client->query.qname, qnamebuf, sizeof(qnamebuf)); + + if (p_name != NULL) { + via = " via "; + dns_name_format(p_name, p_namebuf, sizeof(p_namebuf)); + } else { + via = ""; + p_namebuf[0] = '\0'; + } + + ns_client_log(client, NS_LOGCATEGORY_QUERY_ERRORS, NS_LOGMODULE_QUERY, + level, "rpz %s%s%s rewrite %s%s%s%s%s%s%s", rpztypestr1, + slash, rpztypestr2, qnamebuf, via, p_namebuf, str_blank, + str, failed, isc_result_totext(result)); +} + +static void +rpz_log_fail(ns_client_t *client, int level, dns_name_t *p_name, + dns_rpz_type_t rpz_type, const char *str, isc_result_t result) { + rpz_log_fail_helper(client, level, p_name, rpz_type, DNS_RPZ_TYPE_BAD, + str, result); +} + +/* + * Get a policy rewrite zone database. + */ +static isc_result_t +rpz_getdb(ns_client_t *client, dns_name_t *p_name, dns_rpz_type_t rpz_type, + dns_zone_t **zonep, dns_db_t **dbp, dns_dbversion_t **versionp) { + char qnamebuf[DNS_NAME_FORMATSIZE]; + char p_namebuf[DNS_NAME_FORMATSIZE]; + dns_dbversion_t *rpz_version = NULL; + isc_result_t result; + + CTRACE(ISC_LOG_DEBUG(3), "rpz_getdb"); + + result = query_getzonedb(client, p_name, dns_rdatatype_any, + DNS_GETDB_IGNOREACL, zonep, dbp, &rpz_version); + if (result == ISC_R_SUCCESS) { + dns_rpz_st_t *st = client->query.rpz_st; + + /* + * It isn't meaningful to log this message when + * logging is disabled for some policy zones. + */ + if (st->popt.no_log == 0 && + isc_log_wouldlog(ns_lctx, DNS_RPZ_DEBUG_LEVEL2)) + { + dns_name_format(client->query.qname, qnamebuf, + sizeof(qnamebuf)); + dns_name_format(p_name, p_namebuf, sizeof(p_namebuf)); + ns_client_log(client, DNS_LOGCATEGORY_RPZ, + NS_LOGMODULE_QUERY, DNS_RPZ_DEBUG_LEVEL2, + "try rpz %s rewrite %s via %s", + dns_rpz_type2str(rpz_type), qnamebuf, + p_namebuf); + } + *versionp = rpz_version; + return (ISC_R_SUCCESS); + } + rpz_log_fail(client, DNS_RPZ_ERROR_LEVEL, p_name, rpz_type, + "query_getzonedb()", result); + return (result); +} + +/*% + * 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. + */ +static isc_result_t +query_getcachedb(ns_client_t *client, const dns_name_t *name, + dns_rdatatype_t qtype, dns_db_t **dbp, unsigned int options) { + isc_result_t result; + dns_db_t *db = NULL; + + REQUIRE(dbp != NULL && *dbp == NULL); + + if (!USECACHE(client)) { + return (DNS_R_REFUSED); + } + + dns_db_attach(client->view->cachedb, &db); + + result = query_checkcacheaccess(client, name, qtype, options); + if (result != ISC_R_SUCCESS) { + dns_db_detach(&db); + } + + /* + * If query_checkcacheaccess() succeeded, transfer ownership of 'db'. + * Otherwise, 'db' will be NULL due to the dns_db_detach() call above. + */ + *dbp = db; + + return (result); +} + +static 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, bool *is_zonep) { + isc_result_t result; + isc_result_t tresult; + unsigned int namelabels; + unsigned int zonelabels; + dns_zone_t *zone = NULL; + + REQUIRE(zonep != NULL && *zonep == NULL); + + /* Calculate how many labels are in name. */ + namelabels = dns_name_countlabels(name); + zonelabels = 0; + + /* Try to find name in bind's standard database. */ + result = query_getzonedb(client, name, qtype, options, &zone, dbp, + versionp); + + /* See how many labels are in the zone's name. */ + if (result == ISC_R_SUCCESS && zone != NULL) { + zonelabels = dns_name_countlabels(dns_zone_getorigin(zone)); + } + + /* + * If # zone labels < # name labels, try to find an even better match + * Only try if DLZ drivers are loaded for this view + */ + if (zonelabels < namelabels && + !ISC_LIST_EMPTY(client->view->dlz_searched)) + { + dns_clientinfomethods_t cm; + dns_clientinfo_t ci; + dns_db_t *tdbp; + + dns_clientinfomethods_init(&cm, ns_client_sourceip); + dns_clientinfo_init(&ci, client, NULL); + dns_clientinfo_setecs(&ci, &client->ecs); + + tdbp = NULL; + tresult = dns_view_searchdlz(client->view, name, zonelabels, + &cm, &ci, &tdbp); + /* If we successful, we found a better match. */ + if (tresult == ISC_R_SUCCESS) { + ns_dbversion_t *dbversion; + + /* + * If the previous search returned a zone, detach it. + */ + if (zone != NULL) { + dns_zone_detach(&zone); + } + + /* + * If the previous search returned a database, + * detach it. + */ + if (*dbp != NULL) { + dns_db_detach(dbp); + } + + /* + * If the previous search returned a version, clear it. + */ + *versionp = NULL; + + dbversion = ns_client_findversion(client, tdbp); + if (dbversion == NULL) { + tresult = ISC_R_NOMEMORY; + } else { + /* + * Be sure to return our database. + */ + *dbp = tdbp; + *versionp = dbversion->version; + } + + /* + * We return a null zone, No stats for DLZ zones. + */ + zone = NULL; + result = tresult; + } + } + + /* If successful, Transfer ownership of zone. */ + if (result == ISC_R_SUCCESS) { + *zonep = zone; + /* + * If neither attempt above succeeded, return the cache instead + */ + *is_zonep = true; + } else { + if (result == ISC_R_NOTFOUND) { + result = query_getcachedb(client, name, qtype, dbp, + options); + } + *is_zonep = false; + } + return (result); +} + +static bool +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(ISC_LOG_DEBUG(3), "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(ISC_LOG_DEBUG(3), "query_isduplicate: true: " + "done"); + return (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 (mnamep != NULL) { + *mnamep = mname; + } + + CTRACE(ISC_LOG_DEBUG(3), "query_isduplicate: false: done"); + return (false); +} + +/* + * Look up data for given 'name' and 'type' in given 'version' of 'db' for + * 'client'. Called from query_additionalauth(). + * + * If the lookup is successful: + * + * - store the node containing the result at 'nodep', + * + * - store the owner name of the returned node in 'fname', + * + * - if 'type' is not ANY, dns_db_findext() will put the exact rdataset being + * looked for in 'rdataset' and its signatures (if any) in 'sigrdataset', + * + * - if 'type' is ANY, dns_db_findext() will leave 'rdataset' and + * 'sigrdataset' disassociated and the returned node will be iterated in + * query_additional_cb(). + * + * If the lookup is not successful: + * + * - 'nodep' will not be written to, + * - 'fname' may still be modified as it is passed to dns_db_findext(), + * - 'rdataset' and 'sigrdataset' will remain disassociated. + */ +static isc_result_t +query_additionalauthfind(dns_db_t *db, dns_dbversion_t *version, + const dns_name_t *name, dns_rdatatype_t type, + ns_client_t *client, dns_dbnode_t **nodep, + dns_name_t *fname, dns_rdataset_t *rdataset, + dns_rdataset_t *sigrdataset) { + dns_clientinfomethods_t cm; + dns_dbnode_t *node = NULL; + dns_clientinfo_t ci; + isc_result_t result; + + dns_clientinfomethods_init(&cm, ns_client_sourceip); + dns_clientinfo_init(&ci, client, NULL); + + /* + * 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. + */ + result = dns_db_findext(db, name, version, type, + client->query.dboptions, client->now, &node, + fname, &cm, &ci, rdataset, sigrdataset); + if (result != ISC_R_SUCCESS) { + 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); + } + + return (result); + } + + /* + * Do not return signatures if the zone is not fully signed. + */ + if (sigrdataset != NULL && !dns_db_issecure(db) && + dns_rdataset_isassociated(sigrdataset)) + { + dns_rdataset_disassociate(sigrdataset); + } + + *nodep = node; + + return (ISC_R_SUCCESS); +} + +/* + * For query context 'qctx', try finding authoritative additional data for + * given 'name' and 'type'. Called from query_additional_cb(). + * + * If successful: + * + * - store pointers to the database and node which contain the result in + * 'dbp' and 'nodep', respectively, + * + * - store the owner name of the returned node in 'fname', + * + * - potentially bind 'rdataset' and 'sigrdataset', as explained in the + * comment for query_additionalauthfind(). + * + * If unsuccessful: + * + * - 'dbp' and 'nodep' will not be written to, + * - 'fname' may still be modified as it is passed to dns_db_findext(), + * - 'rdataset' and 'sigrdataset' will remain disassociated. + */ +static isc_result_t +query_additionalauth(query_ctx_t *qctx, const dns_name_t *name, + dns_rdatatype_t type, dns_db_t **dbp, dns_dbnode_t **nodep, + dns_name_t *fname, dns_rdataset_t *rdataset, + dns_rdataset_t *sigrdataset) { + ns_client_t *client = qctx->client; + ns_dbversion_t *dbversion = NULL; + dns_dbversion_t *version = NULL; + dns_dbnode_t *node = NULL; + dns_zone_t *zone = NULL; + dns_db_t *db = NULL; + isc_result_t result; + + /* + * First, look within the same zone database for authoritative + * additional data. + */ + if (!client->query.authdbset || client->query.authdb == NULL) { + return (ISC_R_NOTFOUND); + } + + dbversion = ns_client_findversion(client, client->query.authdb); + if (dbversion == NULL) { + return (ISC_R_NOTFOUND); + } + + dns_db_attach(client->query.authdb, &db); + version = dbversion->version; + + CTRACE(ISC_LOG_DEBUG(3), "query_additionalauth: same zone"); + + result = query_additionalauthfind(db, version, name, type, client, + &node, fname, rdataset, sigrdataset); + if (result != ISC_R_SUCCESS && + qctx->view->minimalresponses == dns_minimal_no && + RECURSIONOK(client)) + { + /* + * If we aren't doing response minimization and recursion is + * allowed, we can try and see if any other zone matches. + */ + version = NULL; + dns_db_detach(&db); + result = query_getzonedb(client, name, type, DNS_GETDB_NOLOG, + &zone, &db, &version); + if (result != ISC_R_SUCCESS) { + return (result); + } + dns_zone_detach(&zone); + + CTRACE(ISC_LOG_DEBUG(3), "query_additionalauth: other zone"); + + result = query_additionalauthfind(db, version, name, type, + client, &node, fname, + rdataset, sigrdataset); + } + + if (result != ISC_R_SUCCESS) { + dns_db_detach(&db); + } else { + *nodep = node; + node = NULL; + + *dbp = db; + db = NULL; + } + + return (result); +} + +static isc_result_t +query_additional_cb(void *arg, const dns_name_t *name, dns_rdatatype_t qtype, + dns_rdataset_t *found) { + query_ctx_t *qctx = arg; + ns_client_t *client = qctx->client; + isc_result_t result, eresult = ISC_R_SUCCESS; + dns_dbnode_t *node = NULL; + dns_db_t *db = NULL; + dns_name_t *fname = NULL, *mname = NULL; + dns_rdataset_t *rdataset = NULL, *sigrdataset = NULL; + dns_rdataset_t *trdataset = NULL; + isc_buffer_t *dbuf = NULL; + isc_buffer_t b; + ns_dbversion_t *dbversion = NULL; + dns_dbversion_t *version = NULL; + bool added_something = false, need_addname = false; + dns_rdatatype_t type; + dns_clientinfomethods_t cm; + dns_clientinfo_t ci; + dns_rdatasetadditional_t additionaltype = + dns_rdatasetadditional_fromauth; + + REQUIRE(NS_CLIENT_VALID(client)); + REQUIRE(qtype != dns_rdatatype_any); + + if (!WANTDNSSEC(client) && dns_rdatatype_isdnssec(qtype)) { + return (ISC_R_SUCCESS); + } + + CTRACE(ISC_LOG_DEBUG(3), "query_additional_cb"); + + dns_clientinfomethods_init(&cm, ns_client_sourceip); + dns_clientinfo_init(&ci, client, 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 = ns_client_getnamebuf(client); + if (dbuf == NULL) { + goto cleanup; + } + fname = ns_client_newname(client, dbuf, &b); + rdataset = ns_client_newrdataset(client); + if (fname == NULL || rdataset == NULL) { + goto cleanup; + } + if (WANTDNSSEC(client)) { + sigrdataset = ns_client_newrdataset(client); + if (sigrdataset == NULL) { + goto cleanup; + } + } + + /* + * If we want only minimal responses and are here, then it must + * be for glue. + */ + if (qctx->view->minimalresponses == dns_minimal_yes && + client->query.qtype != dns_rdatatype_ns) + { + goto try_glue; + } + + /* + * First, look for authoritative additional data. + */ + result = query_additionalauth(qctx, name, type, &db, &node, fname, + rdataset, sigrdataset); + if (result == ISC_R_SUCCESS) { + goto found; + } + + /* + * No authoritative data was found. The cache is our next best bet. + */ + if (!qctx->view->recursion) { + goto try_glue; + } + + additionaltype = dns_rdatasetadditional_fromcache; + 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; + } + /* + * Attempt to validate glue. + */ + if (sigrdataset == NULL) { + sigrdataset = ns_client_newrdataset(client); + if (sigrdataset == NULL) { + goto cleanup; + } + } + + version = NULL; + result = dns_db_findext(db, name, version, type, + client->query.dboptions | DNS_DBFIND_GLUEOK | + DNS_DBFIND_ADDITIONALOK, + client->now, &node, fname, &cm, &ci, rdataset, + sigrdataset); + + dns_cache_updatestats(qctx->view->cache, result); + if (!WANTDNSSEC(client)) { + ns_client_putrdataset(client, &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 poison caches using the bailiwick protection model. + */ + if (!dns_name_issubdomain(name, dns_db_origin(client->query.gluedb))) { + goto cleanup; + } + + dbversion = ns_client_findversion(client, client->query.gluedb); + if (dbversion == NULL) { + goto cleanup; + } + + dns_db_attach(client->query.gluedb, &db); + version = dbversion->version; + additionaltype = dns_rdatasetadditional_fromglue; + result = dns_db_findext(db, name, version, type, + client->query.dboptions | DNS_DBFIND_GLUEOK, + client->now, &node, fname, &cm, &ci, 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. + */ + ns_client_keepname(client, fname, dbuf); + + /* + * Does the caller want the found rdataset? + */ + if (found != NULL && dns_rdataset_isassociated(rdataset)) { + dns_rdataset_clone(rdataset, found); + } + + /* + * 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) { + INSIST(mname != fname); + ns_client_releasename(client, &fname); + fname = mname; + } else { + need_addname = true; + } + ISC_LIST_APPEND(fname->list, rdataset, link); + trdataset = rdataset; + rdataset = NULL; + added_something = 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 = ns_client_newrdataset(client); + if (rdataset == NULL) { + goto addname; + } + } + if (sigrdataset != NULL) { + if (dns_rdataset_isassociated(sigrdataset)) { + dns_rdataset_disassociate(sigrdataset); + } + } else if (WANTDNSSEC(client)) { + sigrdataset = ns_client_newrdataset(client); + if (sigrdataset == NULL) { + goto addname; + } + } + if (query_isduplicate(client, fname, dns_rdatatype_a, NULL)) { + goto aaaa_lookup; + } + result = dns_db_findrdataset(db, node, version, dns_rdatatype_a, + 0, client->now, rdataset, + sigrdataset); + if (result == DNS_R_NCACHENXDOMAIN) { + goto addname; + } else if (result == DNS_R_NCACHENXRRSET) { + dns_rdataset_disassociate(rdataset); + if (sigrdataset != NULL && + dns_rdataset_isassociated(sigrdataset)) + { + dns_rdataset_disassociate(sigrdataset); + } + } else if (result == ISC_R_SUCCESS) { + bool invalid = false; + mname = NULL; + if (additionaltype == + dns_rdatasetadditional_fromcache && + (DNS_TRUST_PENDING(rdataset->trust) || + DNS_TRUST_GLUE(rdataset->trust))) + { + /* validate() may change rdataset->trust */ + invalid = !validate(client, db, fname, rdataset, + sigrdataset); + } + if (invalid && DNS_TRUST_PENDING(rdataset->trust)) { + dns_rdataset_disassociate(rdataset); + if (sigrdataset != NULL && + dns_rdataset_isassociated(sigrdataset)) + { + dns_rdataset_disassociate(sigrdataset); + } + } else if (!query_isduplicate(client, fname, + dns_rdatatype_a, &mname)) + { + if (mname != fname) { + if (mname != NULL) { + ns_client_releasename(client, + &fname); + fname = mname; + } else { + need_addname = true; + } + } + ISC_LIST_APPEND(fname->list, rdataset, link); + added_something = true; + if (sigrdataset != NULL && + dns_rdataset_isassociated(sigrdataset)) + { + ISC_LIST_APPEND(fname->list, + sigrdataset, link); + sigrdataset = + ns_client_newrdataset(client); + } + rdataset = ns_client_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); + } + } + } + aaaa_lookup: + if (query_isduplicate(client, fname, dns_rdatatype_aaaa, NULL)) + { + goto addname; + } + result = dns_db_findrdataset(db, node, version, + dns_rdatatype_aaaa, 0, client->now, + rdataset, sigrdataset); + if (result == DNS_R_NCACHENXDOMAIN) { + goto addname; + } else if (result == DNS_R_NCACHENXRRSET) { + dns_rdataset_disassociate(rdataset); + if (sigrdataset != NULL && + dns_rdataset_isassociated(sigrdataset)) + { + dns_rdataset_disassociate(sigrdataset); + } + } else if (result == ISC_R_SUCCESS) { + bool invalid = false; + mname = NULL; + + if (additionaltype == + dns_rdatasetadditional_fromcache && + (DNS_TRUST_PENDING(rdataset->trust) || + DNS_TRUST_GLUE(rdataset->trust))) + { + /* validate() may change rdataset->trust */ + invalid = !validate(client, db, fname, rdataset, + sigrdataset); + } + + if (invalid && DNS_TRUST_PENDING(rdataset->trust)) { + dns_rdataset_disassociate(rdataset); + if (sigrdataset != NULL && + dns_rdataset_isassociated(sigrdataset)) + { + dns_rdataset_disassociate(sigrdataset); + } + } else if (!query_isduplicate(client, fname, + dns_rdatatype_aaaa, + &mname)) + { + if (mname != fname) { + if (mname != NULL) { + ns_client_releasename(client, + &fname); + fname = mname; + } else { + need_addname = true; + } + } + ISC_LIST_APPEND(fname->list, rdataset, link); + added_something = true; + if (sigrdataset != NULL && + dns_rdataset_isassociated(sigrdataset)) + { + ISC_LIST_APPEND(fname->list, + sigrdataset, link); + sigrdataset = NULL; + } + rdataset = NULL; + } + } + } + +addname: + CTRACE(ISC_LOG_DEBUG(3), "query_additional_cb: 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 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); + } + + /* + * In some cases, a record that has been added as additional + * data may *also* trigger the addition of additional data. + * This cannot go more than MAX_RESTARTS levels deep. + */ + if (trdataset != NULL && dns_rdatatype_followadditional(type)) { + if (client->additionaldepth++ < MAX_RESTARTS) { + eresult = dns_rdataset_additionaldata( + trdataset, fname, query_additional_cb, qctx); + } + client->additionaldepth--; + } + + /* + * Don't release fname. + */ + fname = NULL; + +cleanup: + CTRACE(ISC_LOG_DEBUG(3), "query_additional_cb: cleanup"); + ns_client_putrdataset(client, &rdataset); + if (sigrdataset != NULL) { + ns_client_putrdataset(client, &sigrdataset); + } + if (fname != NULL) { + ns_client_releasename(client, &fname); + } + if (node != NULL) { + dns_db_detachnode(db, &node); + } + if (db != NULL) { + dns_db_detach(&db); + } + + CTRACE(ISC_LOG_DEBUG(3), "query_additional_cb: done"); + return (eresult); +} + +/* + * Add 'rdataset' to 'name'. + */ +static void +query_addtoname(dns_name_t *name, dns_rdataset_t *rdataset) { + ISC_LIST_APPEND(name->list, rdataset, link); +} + +/* + * Set the ordering for 'rdataset'. + */ +static void +query_setorder(query_ctx_t *qctx, dns_name_t *name, dns_rdataset_t *rdataset) { + ns_client_t *client = qctx->client; + dns_order_t *order = client->view->order; + + CTRACE(ISC_LOG_DEBUG(3), "query_setorder"); + + UNUSED(client); + + if (order != NULL) { + rdataset->attributes |= dns_order_find( + order, name, rdataset->type, rdataset->rdclass); + } + rdataset->attributes |= DNS_RDATASETATTR_LOADORDER; +} + +/* + * Handle glue and fetch any other needed additional data for 'rdataset'. + */ +static void +query_additional(query_ctx_t *qctx, dns_name_t *name, + dns_rdataset_t *rdataset) { + ns_client_t *client = qctx->client; + isc_result_t result; + + CTRACE(ISC_LOG_DEBUG(3), "query_additional"); + + if (NOADDITIONAL(client)) { + return; + } + + /* + * Try to process glue directly. + */ + if (qctx->view->use_glue_cache && + (rdataset->type == dns_rdatatype_ns) && + (client->query.gluedb != NULL) && + dns_db_iszone(client->query.gluedb)) + { + ns_dbversion_t *dbversion; + + dbversion = ns_client_findversion(client, client->query.gluedb); + if (dbversion == NULL) { + goto regular; + } + + result = dns_rdataset_addglue(rdataset, dbversion->version, + client->message); + if (result == ISC_R_SUCCESS) { + return; + } + } + +regular: + /* + * Add other additional data if needed. + * We don't care if dns_rdataset_additionaldata() fails. + */ + (void)dns_rdataset_additionaldata(rdataset, name, query_additional_cb, + qctx); + CTRACE(ISC_LOG_DEBUG(3), "query_additional: done"); +} + +static void +query_addrrset(query_ctx_t *qctx, dns_name_t **namep, + dns_rdataset_t **rdatasetp, dns_rdataset_t **sigrdatasetp, + isc_buffer_t *dbuf, dns_section_t section) { + isc_result_t result; + ns_client_t *client = qctx->client; + dns_name_t *name = *namep, *mname = NULL; + dns_rdataset_t *rdataset = *rdatasetp, *mrdataset = NULL; + dns_rdataset_t *sigrdataset = NULL; + + CTRACE(ISC_LOG_DEBUG(3), "query_addrrset"); + + REQUIRE(name != NULL); + + if (sigrdatasetp != NULL) { + sigrdataset = *sigrdatasetp; + } + + /*% + * 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. + */ + 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. + */ + CTRACE(ISC_LOG_DEBUG(3), "query_addrrset: dns_message_findname " + "succeeded: done"); + if (dbuf != NULL) { + ns_client_releasename(client, namep); + } + if ((rdataset->attributes & DNS_RDATASETATTR_REQUIRED) != 0) { + mrdataset->attributes |= DNS_RDATASETATTR_REQUIRED; + } + if ((rdataset->attributes & DNS_RDATASETATTR_STALE_ADDED) != 0) + { + mrdataset->attributes |= DNS_RDATASETATTR_STALE_ADDED; + } + return; + } else if (result == DNS_R_NXDOMAIN) { + /* + * The name doesn't exist. + */ + if (dbuf != NULL) { + ns_client_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) { + ns_client_releasename(client, namep); + } + } + + if (rdataset->trust != dns_trust_secure && + (section == DNS_SECTION_ANSWER || section == DNS_SECTION_AUTHORITY)) + { + client->query.attributes &= ~NS_QUERYATTR_SECURE; + } + + /* + * Update message name, set rdataset order, and do additional + * section processing if needed. + */ + query_addtoname(mname, rdataset); + query_setorder(qctx, mname, rdataset); + query_additional(qctx, mname, rdataset); + + /* + * 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. + */ + *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(ISC_LOG_DEBUG(3), "query_addrrset: done"); +} + +/* + * Mark the RRsets as secure. Update the cache (db) to reflect the + * change in trust level. + */ +static void +mark_secure(ns_client_t *client, dns_db_t *db, dns_name_t *name, + dns_rdata_rrsig_t *rrsig, dns_rdataset_t *rdataset, + dns_rdataset_t *sigrdataset) { + isc_result_t result; + dns_dbnode_t *node = NULL; + dns_clientinfomethods_t cm; + dns_clientinfo_t ci; + isc_stdtime_t now; + + rdataset->trust = dns_trust_secure; + sigrdataset->trust = dns_trust_secure; + dns_clientinfomethods_init(&cm, ns_client_sourceip); + dns_clientinfo_init(&ci, client, NULL); + + /* + * Save the updated secure state. Ignore failures. + */ + result = dns_db_findnodeext(db, name, true, &cm, &ci, &node); + if (result != ISC_R_SUCCESS) { + return; + } + + isc_stdtime_get(&now); + dns_rdataset_trimttl(rdataset, sigrdataset, rrsig, now, + client->view->acceptexpired); + + (void)dns_db_addrdataset(db, node, NULL, client->now, rdataset, 0, + NULL); + (void)dns_db_addrdataset(db, node, NULL, client->now, sigrdataset, 0, + NULL); + dns_db_detachnode(db, &node); +} + +/* + * Find the secure key that corresponds to rrsig. + * Note: 'keyrdataset' maintains state between successive calls, + * there may be multiple keys with the same keyid. + * Return false if we have exhausted all the possible keys. + */ +static bool +get_key(ns_client_t *client, dns_db_t *db, dns_rdata_rrsig_t *rrsig, + dns_rdataset_t *keyrdataset, dst_key_t **keyp) { + isc_result_t result; + dns_dbnode_t *node = NULL; + bool secure = false; + dns_clientinfomethods_t cm; + dns_clientinfo_t ci; + + dns_clientinfomethods_init(&cm, ns_client_sourceip); + dns_clientinfo_init(&ci, client, NULL); + + if (!dns_rdataset_isassociated(keyrdataset)) { + result = dns_db_findnodeext(db, &rrsig->signer, false, &cm, &ci, + &node); + if (result != ISC_R_SUCCESS) { + return (false); + } + + result = dns_db_findrdataset(db, node, NULL, + dns_rdatatype_dnskey, 0, + client->now, keyrdataset, NULL); + dns_db_detachnode(db, &node); + if (result != ISC_R_SUCCESS) { + return (false); + } + + if (keyrdataset->trust != dns_trust_secure) { + return (false); + } + + result = dns_rdataset_first(keyrdataset); + } else { + result = dns_rdataset_next(keyrdataset); + } + + for (; result == ISC_R_SUCCESS; result = dns_rdataset_next(keyrdataset)) + { + dns_rdata_t rdata = DNS_RDATA_INIT; + isc_buffer_t b; + + dns_rdataset_current(keyrdataset, &rdata); + isc_buffer_init(&b, rdata.data, rdata.length); + isc_buffer_add(&b, rdata.length); + result = dst_key_fromdns(&rrsig->signer, rdata.rdclass, &b, + client->mctx, keyp); + if (result != ISC_R_SUCCESS) { + continue; + } + if (rrsig->algorithm == (dns_secalg_t)dst_key_alg(*keyp) && + rrsig->keyid == (dns_keytag_t)dst_key_id(*keyp) && + dst_key_iszonekey(*keyp)) + { + secure = true; + break; + } + dst_key_free(keyp); + } + return (secure); +} + +static bool +verify(dst_key_t *key, dns_name_t *name, dns_rdataset_t *rdataset, + dns_rdata_t *rdata, ns_client_t *client) { + isc_result_t result; + dns_fixedname_t fixed; + bool ignore = false; + + dns_fixedname_init(&fixed); + +again: + result = dns_dnssec_verify(name, rdataset, key, ignore, + client->view->maxbits, client->mctx, rdata, + NULL); + if (result == DNS_R_SIGEXPIRED && client->view->acceptexpired) { + ignore = true; + goto again; + } + if (result == ISC_R_SUCCESS || result == DNS_R_FROMWILDCARD) { + return (true); + } + return (false); +} + +/* + * Validate the rdataset if possible with available records. + */ +static bool +validate(ns_client_t *client, dns_db_t *db, dns_name_t *name, + dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset) { + isc_result_t result; + dns_rdata_t rdata = DNS_RDATA_INIT; + dns_rdata_rrsig_t rrsig; + dst_key_t *key = NULL; + dns_rdataset_t keyrdataset; + + if (sigrdataset == NULL || !dns_rdataset_isassociated(sigrdataset)) { + return (false); + } + + for (result = dns_rdataset_first(sigrdataset); result == ISC_R_SUCCESS; + result = dns_rdataset_next(sigrdataset)) + { + dns_rdata_reset(&rdata); + dns_rdataset_current(sigrdataset, &rdata); + result = dns_rdata_tostruct(&rdata, &rrsig, NULL); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + if (!dns_resolver_algorithm_supported(client->view->resolver, + name, rrsig.algorithm)) + { + continue; + } + if (!dns_name_issubdomain(name, &rrsig.signer)) { + continue; + } + dns_rdataset_init(&keyrdataset); + do { + if (!get_key(client, db, &rrsig, &keyrdataset, &key)) { + break; + } + if (verify(key, name, rdataset, &rdata, client)) { + dst_key_free(&key); + dns_rdataset_disassociate(&keyrdataset); + mark_secure(client, db, name, &rrsig, rdataset, + sigrdataset); + return (true); + } + dst_key_free(&key); + } while (1); + if (dns_rdataset_isassociated(&keyrdataset)) { + dns_rdataset_disassociate(&keyrdataset); + } + } + return (false); +} + +static void +fixrdataset(ns_client_t *client, dns_rdataset_t **rdataset) { + if (*rdataset == NULL) { + *rdataset = ns_client_newrdataset(client); + } else if (dns_rdataset_isassociated(*rdataset)) { + dns_rdataset_disassociate(*rdataset); + } +} + +static void +fixfname(ns_client_t *client, dns_name_t **fname, isc_buffer_t **dbuf, + isc_buffer_t *nbuf) { + if (*fname == NULL) { + *dbuf = ns_client_getnamebuf(client); + if (*dbuf == NULL) { + return; + } + *fname = ns_client_newname(client, *dbuf, nbuf); + } +} + +static void +free_devent(ns_client_t *client, isc_event_t **eventp, + dns_fetchevent_t **deventp) { + dns_fetchevent_t *devent = *deventp; + + REQUIRE((void *)(*eventp) == (void *)(*deventp)); + + CTRACE(ISC_LOG_DEBUG(3), "free_devent"); + + if (devent->fetch != NULL) { + dns_resolver_destroyfetch(&devent->fetch); + } + if (devent->node != NULL) { + dns_db_detachnode(devent->db, &devent->node); + } + if (devent->db != NULL) { + dns_db_detach(&devent->db); + } + if (devent->rdataset != NULL) { + ns_client_putrdataset(client, &devent->rdataset); + } + if (devent->sigrdataset != NULL) { + ns_client_putrdataset(client, &devent->sigrdataset); + } + + /* + * If the two pointers are the same then leave the setting of + * (*deventp) to NULL to isc_event_free. + */ + if ((void *)eventp != (void *)deventp) { + (*deventp) = NULL; + } + isc_event_free(eventp); +} + +static void +prefetch_done(isc_task_t *task, isc_event_t *event) { + dns_fetchevent_t *devent = (dns_fetchevent_t *)event; + ns_client_t *client; + + UNUSED(task); + + REQUIRE(event->ev_type == DNS_EVENT_FETCHDONE); + client = devent->ev_arg; + REQUIRE(NS_CLIENT_VALID(client)); + REQUIRE(task == client->task); + + CTRACE(ISC_LOG_DEBUG(3), "prefetch_done"); + + LOCK(&client->query.fetchlock); + if (client->query.prefetch != NULL) { + INSIST(devent->fetch == client->query.prefetch); + client->query.prefetch = NULL; + } + UNLOCK(&client->query.fetchlock); + + /* + * We're done prefetching, detach from quota. + */ + if (client->recursionquota != NULL) { + isc_quota_detach(&client->recursionquota); + ns_stats_decrement(client->sctx->nsstats, + ns_statscounter_recursclients); + } + + free_devent(client, &event, &devent); + isc_nmhandle_detach(&client->prefetchhandle); +} + +static void +query_prefetch(ns_client_t *client, dns_name_t *qname, + dns_rdataset_t *rdataset) { + isc_result_t result; + isc_sockaddr_t *peeraddr; + dns_rdataset_t *tmprdataset; + unsigned int options; + + CTRACE(ISC_LOG_DEBUG(3), "query_prefetch"); + + if (client->query.prefetch != NULL || + client->view->prefetch_trigger == 0U || + rdataset->ttl > client->view->prefetch_trigger || + (rdataset->attributes & DNS_RDATASETATTR_PREFETCH) == 0) + { + return; + } + + if (client->recursionquota == NULL) { + result = isc_quota_attach(&client->sctx->recursionquota, + &client->recursionquota); + switch (result) { + case ISC_R_SUCCESS: + ns_stats_increment(client->sctx->nsstats, + ns_statscounter_recursclients); + break; + case ISC_R_SOFTQUOTA: + isc_quota_detach(&client->recursionquota); + FALLTHROUGH; + default: + return; + } + } + + tmprdataset = ns_client_newrdataset(client); + if (tmprdataset == NULL) { + return; + } + + if (!TCP(client)) { + peeraddr = &client->peeraddr; + } else { + peeraddr = NULL; + } + + isc_nmhandle_attach(client->handle, &client->prefetchhandle); + options = client->query.fetchoptions | DNS_FETCHOPT_PREFETCH; + result = dns_resolver_createfetch( + client->view->resolver, qname, rdataset->type, NULL, NULL, NULL, + peeraddr, client->message->id, options, 0, NULL, client->task, + prefetch_done, client, tmprdataset, NULL, + &client->query.prefetch); + if (result != ISC_R_SUCCESS) { + ns_client_putrdataset(client, &tmprdataset); + isc_nmhandle_detach(&client->prefetchhandle); + } + + dns_rdataset_clearprefetch(rdataset); + ns_stats_increment(client->sctx->nsstats, ns_statscounter_prefetch); +} + +static void +rpz_clean(dns_zone_t **zonep, dns_db_t **dbp, dns_dbnode_t **nodep, + dns_rdataset_t **rdatasetp) { + if (nodep != NULL && *nodep != NULL) { + REQUIRE(dbp != NULL && *dbp != NULL); + dns_db_detachnode(*dbp, nodep); + } + if (dbp != NULL && *dbp != NULL) { + dns_db_detach(dbp); + } + if (zonep != NULL && *zonep != NULL) { + dns_zone_detach(zonep); + } + if (rdatasetp != NULL && *rdatasetp != NULL && + dns_rdataset_isassociated(*rdatasetp)) + { + dns_rdataset_disassociate(*rdatasetp); + } +} + +static void +rpz_match_clear(dns_rpz_st_t *st) { + rpz_clean(&st->m.zone, &st->m.db, &st->m.node, &st->m.rdataset); + st->m.version = NULL; +} + +static isc_result_t +rpz_ready(ns_client_t *client, dns_rdataset_t **rdatasetp) { + REQUIRE(rdatasetp != NULL); + + CTRACE(ISC_LOG_DEBUG(3), "rpz_ready"); + + if (*rdatasetp == NULL) { + *rdatasetp = ns_client_newrdataset(client); + if (*rdatasetp == NULL) { + CTRACE(ISC_LOG_ERROR, "rpz_ready: " + "ns_client_newrdataset failed"); + return (DNS_R_SERVFAIL); + } + } else if (dns_rdataset_isassociated(*rdatasetp)) { + dns_rdataset_disassociate(*rdatasetp); + } + return (ISC_R_SUCCESS); +} + +static void +rpz_st_clear(ns_client_t *client) { + dns_rpz_st_t *st = client->query.rpz_st; + + CTRACE(ISC_LOG_DEBUG(3), "rpz_st_clear"); + + if (st->m.rdataset != NULL) { + ns_client_putrdataset(client, &st->m.rdataset); + } + rpz_match_clear(st); + + rpz_clean(NULL, &st->r.db, NULL, NULL); + if (st->r.ns_rdataset != NULL) { + ns_client_putrdataset(client, &st->r.ns_rdataset); + } + if (st->r.r_rdataset != NULL) { + ns_client_putrdataset(client, &st->r.r_rdataset); + } + + rpz_clean(&st->q.zone, &st->q.db, &st->q.node, NULL); + if (st->q.rdataset != NULL) { + ns_client_putrdataset(client, &st->q.rdataset); + } + if (st->q.sigrdataset != NULL) { + ns_client_putrdataset(client, &st->q.sigrdataset); + } + st->state = 0; + st->m.type = DNS_RPZ_TYPE_BAD; + st->m.policy = DNS_RPZ_POLICY_MISS; + if (st->rpsdb != NULL) { + dns_db_detach(&st->rpsdb); + } +} + +static dns_rpz_zbits_t +rpz_get_zbits(ns_client_t *client, dns_rdatatype_t ip_type, + dns_rpz_type_t rpz_type) { + dns_rpz_st_t *st; + dns_rpz_zbits_t zbits = 0; + + REQUIRE(client != NULL); + REQUIRE(client->query.rpz_st != NULL); + + st = client->query.rpz_st; + +#ifdef USE_DNSRPS + if (st->popt.dnsrps_enabled) { + if (st->rpsdb == NULL || + librpz->have_trig(dns_dnsrps_type2trig(rpz_type), + ip_type == dns_rdatatype_aaaa, + ((rpsdb_t *)st->rpsdb)->rsp)) + { + return (DNS_RPZ_ALL_ZBITS); + } + return (0); + } +#endif /* ifdef USE_DNSRPS */ + + switch (rpz_type) { + case DNS_RPZ_TYPE_CLIENT_IP: + zbits = st->have.client_ip; + break; + case DNS_RPZ_TYPE_QNAME: + zbits = st->have.qname; + break; + case DNS_RPZ_TYPE_IP: + if (ip_type == dns_rdatatype_a) { + zbits = st->have.ipv4; + } else if (ip_type == dns_rdatatype_aaaa) { + zbits = st->have.ipv6; + } else { + zbits = st->have.ip; + } + break; + case DNS_RPZ_TYPE_NSDNAME: + zbits = st->have.nsdname; + break; + case DNS_RPZ_TYPE_NSIP: + if (ip_type == dns_rdatatype_a) { + zbits = st->have.nsipv4; + } else if (ip_type == dns_rdatatype_aaaa) { + zbits = st->have.nsipv6; + } else { + zbits = st->have.nsip; + } + break; + default: + UNREACHABLE(); + } + + /* + * Choose + * the earliest configured policy zone (rpz->num) + * QNAME over IP over NSDNAME over NSIP (rpz_type) + * the smallest name, + * the longest IP address prefix, + * the lexically smallest address. + */ + if (st->m.policy != DNS_RPZ_POLICY_MISS) { + if (st->m.type >= rpz_type) { + zbits &= DNS_RPZ_ZMASK(st->m.rpz->num); + } else { + zbits &= DNS_RPZ_ZMASK(st->m.rpz->num) >> 1; + } + } + + /* + * If the client wants recursion, allow only compatible policies. + */ + if (!RECURSIONOK(client)) { + zbits &= st->popt.no_rd_ok; + } + + return (zbits); +} + +static void +query_rpzfetch(ns_client_t *client, dns_name_t *qname, dns_rdatatype_t type) { + isc_result_t result; + isc_sockaddr_t *peeraddr; + dns_rdataset_t *tmprdataset; + unsigned int options; + + CTRACE(ISC_LOG_DEBUG(3), "query_rpzfetch"); + + if (client->query.prefetch != NULL) { + return; + } + + if (client->recursionquota == NULL) { + result = isc_quota_attach(&client->sctx->recursionquota, + &client->recursionquota); + switch (result) { + case ISC_R_SUCCESS: + ns_stats_increment(client->sctx->nsstats, + ns_statscounter_recursclients); + break; + case ISC_R_SOFTQUOTA: + isc_quota_detach(&client->recursionquota); + FALLTHROUGH; + default: + return; + } + } + + tmprdataset = ns_client_newrdataset(client); + if (tmprdataset == NULL) { + return; + } + + if (!TCP(client)) { + peeraddr = &client->peeraddr; + } else { + peeraddr = NULL; + } + + options = client->query.fetchoptions; + isc_nmhandle_attach(client->handle, &client->prefetchhandle); + result = dns_resolver_createfetch( + client->view->resolver, qname, type, NULL, NULL, NULL, peeraddr, + client->message->id, options, 0, NULL, client->task, + prefetch_done, client, tmprdataset, NULL, + &client->query.prefetch); + if (result != ISC_R_SUCCESS) { + ns_client_putrdataset(client, &tmprdataset); + isc_nmhandle_detach(&client->prefetchhandle); + } +} + +/* + * Get an NS, A, or AAAA rrset related to the response for the client + * to check the contents of that rrset for hits by eligible policy zones. + */ +static isc_result_t +rpz_rrset_find(ns_client_t *client, dns_name_t *name, dns_rdatatype_t type, + unsigned int options, dns_rpz_type_t rpz_type, dns_db_t **dbp, + dns_dbversion_t *version, dns_rdataset_t **rdatasetp, + bool resuming) { + dns_rpz_st_t *st; + bool is_zone; + dns_dbnode_t *node; + dns_fixedname_t fixed; + dns_name_t *found; + isc_result_t result; + dns_clientinfomethods_t cm; + dns_clientinfo_t ci; + + CTRACE(ISC_LOG_DEBUG(3), "rpz_rrset_find"); + + st = client->query.rpz_st; + if ((st->state & DNS_RPZ_RECURSING) != 0) { + INSIST(st->r.r_type == type); + INSIST(dns_name_equal(name, st->r_name)); + INSIST(*rdatasetp == NULL || + !dns_rdataset_isassociated(*rdatasetp)); + st->state &= ~DNS_RPZ_RECURSING; + RESTORE(*dbp, st->r.db); + if (*rdatasetp != NULL) { + ns_client_putrdataset(client, rdatasetp); + } + RESTORE(*rdatasetp, st->r.r_rdataset); + result = st->r.r_result; + if (result == DNS_R_DELEGATION) { + CTRACE(ISC_LOG_ERROR, "RPZ recursing"); + rpz_log_fail(client, DNS_RPZ_ERROR_LEVEL, name, + rpz_type, "rpz_rrset_find(1)", result); + st->m.policy = DNS_RPZ_POLICY_ERROR; + result = DNS_R_SERVFAIL; + } + return (result); + } + + result = rpz_ready(client, rdatasetp); + if (result != ISC_R_SUCCESS) { + st->m.policy = DNS_RPZ_POLICY_ERROR; + return (result); + } + if (*dbp != NULL) { + is_zone = false; + } else { + dns_zone_t *zone; + + version = NULL; + zone = NULL; + result = query_getdb(client, name, type, 0, &zone, dbp, + &version, &is_zone); + if (result != ISC_R_SUCCESS) { + rpz_log_fail(client, DNS_RPZ_ERROR_LEVEL, name, + rpz_type, "rpz_rrset_find(2)", result); + st->m.policy = DNS_RPZ_POLICY_ERROR; + if (zone != NULL) { + dns_zone_detach(&zone); + } + return (result); + } + if (zone != NULL) { + dns_zone_detach(&zone); + } + } + + node = NULL; + found = dns_fixedname_initname(&fixed); + dns_clientinfomethods_init(&cm, ns_client_sourceip); + dns_clientinfo_init(&ci, client, NULL); + result = dns_db_findext(*dbp, name, version, type, options, client->now, + &node, found, &cm, &ci, *rdatasetp, NULL); + if (result == DNS_R_DELEGATION && is_zone && USECACHE(client)) { + /* + * Try the cache if we're authoritative for an + * ancestor but not the domain itself. + */ + rpz_clean(NULL, dbp, &node, rdatasetp); + version = NULL; + dns_db_attach(client->view->cachedb, dbp); + result = dns_db_findext(*dbp, name, version, type, 0, + client->now, &node, found, &cm, &ci, + *rdatasetp, NULL); + } + rpz_clean(NULL, dbp, &node, NULL); + if (result == DNS_R_DELEGATION) { + rpz_clean(NULL, NULL, NULL, rdatasetp); + /* + * Recurse for NS rrset or A or AAAA rrset for an NS. + * Do not recurse for addresses for the query name. + */ + if (rpz_type == DNS_RPZ_TYPE_IP) { + result = DNS_R_NXRRSET; + } else if (!client->view->rpzs->p.nsip_wait_recurse || + (!client->view->rpzs->p.nsdname_wait_recurse && + rpz_type == DNS_RPZ_TYPE_NSDNAME)) + { + query_rpzfetch(client, name, type); + result = DNS_R_NXRRSET; + } else { + dns_name_copy(name, st->r_name); + result = ns_query_recurse(client, type, st->r_name, + NULL, NULL, resuming); + if (result == ISC_R_SUCCESS) { + st->state |= DNS_RPZ_RECURSING; + result = DNS_R_DELEGATION; + } + } + } + return (result); +} + +/* + * Compute a policy owner name, p_name, in a policy zone given the needed + * policy type and the trigger name. + */ +static isc_result_t +rpz_get_p_name(ns_client_t *client, dns_name_t *p_name, dns_rpz_zone_t *rpz, + dns_rpz_type_t rpz_type, dns_name_t *trig_name) { + dns_offsets_t prefix_offsets; + dns_name_t prefix, *suffix; + unsigned int first, labels; + isc_result_t result; + + CTRACE(ISC_LOG_DEBUG(3), "rpz_get_p_name"); + + /* + * The policy owner name consists of a suffix depending on the type + * and policy zone and a prefix that is the longest possible string + * from the trigger name that keesp the resulting policy owner name + * from being too long. + */ + switch (rpz_type) { + case DNS_RPZ_TYPE_CLIENT_IP: + suffix = &rpz->client_ip; + break; + case DNS_RPZ_TYPE_QNAME: + suffix = &rpz->origin; + break; + case DNS_RPZ_TYPE_IP: + suffix = &rpz->ip; + break; + case DNS_RPZ_TYPE_NSDNAME: + suffix = &rpz->nsdname; + break; + case DNS_RPZ_TYPE_NSIP: + suffix = &rpz->nsip; + break; + default: + UNREACHABLE(); + } + + /* + * Start with relative version of the full trigger name, + * and trim enough allow the addition of the suffix. + */ + dns_name_init(&prefix, prefix_offsets); + labels = dns_name_countlabels(trig_name); + first = 0; + for (;;) { + dns_name_getlabelsequence(trig_name, first, labels - first - 1, + &prefix); + result = dns_name_concatenate(&prefix, suffix, p_name, NULL); + if (result == ISC_R_SUCCESS) { + break; + } + INSIST(result == DNS_R_NAMETOOLONG); + /* + * Trim the trigger name until the combination is not too long. + */ + if (labels - first < 2) { + rpz_log_fail(client, DNS_RPZ_ERROR_LEVEL, suffix, + rpz_type, "concatenate()", result); + return (ISC_R_FAILURE); + } + /* + * Complain once about trimming the trigger name. + */ + if (first == 0) { + rpz_log_fail(client, DNS_RPZ_DEBUG_LEVEL1, suffix, + rpz_type, "concatenate()", result); + } + ++first; + } + return (ISC_R_SUCCESS); +} + +/* + * Look in policy zone rpz for a policy of rpz_type by p_name. + * The self-name (usually the client qname or an NS name) is compared with + * the target of a CNAME policy for the old style passthru encoding. + * If found, the policy is recorded in *zonep, *dbp, *versionp, *nodep, + * *rdatasetp, and *policyp. + * The target DNS type, qtype, chooses the best rdataset for *rdatasetp. + * The caller must decide if the found policy is most suitable, including + * better than a previously found policy. + * If it is best, the caller records it in client->query.rpz_st->m. + */ +static isc_result_t +rpz_find_p(ns_client_t *client, dns_name_t *self_name, dns_rdatatype_t qtype, + dns_name_t *p_name, dns_rpz_zone_t *rpz, dns_rpz_type_t rpz_type, + dns_zone_t **zonep, dns_db_t **dbp, dns_dbversion_t **versionp, + dns_dbnode_t **nodep, dns_rdataset_t **rdatasetp, + dns_rpz_policy_t *policyp) { + dns_fixedname_t foundf; + dns_name_t *found; + isc_result_t result; + dns_clientinfomethods_t cm; + dns_clientinfo_t ci; + bool found_a = false; + + REQUIRE(nodep != NULL); + + CTRACE(ISC_LOG_DEBUG(3), "rpz_find_p"); + + dns_clientinfomethods_init(&cm, ns_client_sourceip); + dns_clientinfo_init(&ci, client, NULL); + + /* + * Try to find either a CNAME or the type of record demanded by the + * request from the policy zone. + */ + rpz_clean(zonep, dbp, nodep, rdatasetp); + result = rpz_ready(client, rdatasetp); + if (result != ISC_R_SUCCESS) { + CTRACE(ISC_LOG_ERROR, "rpz_ready() failed"); + return (DNS_R_SERVFAIL); + } + *versionp = NULL; + result = rpz_getdb(client, p_name, rpz_type, zonep, dbp, versionp); + if (result != ISC_R_SUCCESS) { + return (DNS_R_NXDOMAIN); + } + found = dns_fixedname_initname(&foundf); + + result = dns_db_findext(*dbp, p_name, *versionp, dns_rdatatype_any, 0, + client->now, nodep, found, &cm, &ci, *rdatasetp, + NULL); + /* + * Choose the best rdataset if we found something. + */ + if (result == ISC_R_SUCCESS) { + dns_rdatasetiter_t *rdsiter; + + rdsiter = NULL; + result = dns_db_allrdatasets(*dbp, *nodep, *versionp, 0, 0, + &rdsiter); + if (result != ISC_R_SUCCESS) { + rpz_log_fail(client, DNS_RPZ_ERROR_LEVEL, p_name, + rpz_type, "allrdatasets()", result); + CTRACE(ISC_LOG_ERROR, + "rpz_find_p: allrdatasets failed"); + return (DNS_R_SERVFAIL); + } + if (qtype == dns_rdatatype_aaaa && + !ISC_LIST_EMPTY(client->view->dns64)) + { + for (result = dns_rdatasetiter_first(rdsiter); + result == ISC_R_SUCCESS; + result = dns_rdatasetiter_next(rdsiter)) + { + dns_rdatasetiter_current(rdsiter, *rdatasetp); + if ((*rdatasetp)->type == dns_rdatatype_a) { + found_a = true; + } + dns_rdataset_disassociate(*rdatasetp); + } + } + for (result = dns_rdatasetiter_first(rdsiter); + result == ISC_R_SUCCESS; + result = dns_rdatasetiter_next(rdsiter)) + { + dns_rdatasetiter_current(rdsiter, *rdatasetp); + if ((*rdatasetp)->type == dns_rdatatype_cname || + (*rdatasetp)->type == qtype) + { + break; + } + dns_rdataset_disassociate(*rdatasetp); + } + dns_rdatasetiter_destroy(&rdsiter); + if (result != ISC_R_SUCCESS) { + if (result != ISC_R_NOMORE) { + rpz_log_fail(client, DNS_RPZ_ERROR_LEVEL, + p_name, rpz_type, "rdatasetiter", + result); + CTRACE(ISC_LOG_ERROR, "rpz_find_p: " + "rdatasetiter failed"); + return (DNS_R_SERVFAIL); + } + /* + * Ask again to get the right DNS_R_DNAME/NXRRSET/... + * result if there is neither a CNAME nor target type. + */ + if (dns_rdataset_isassociated(*rdatasetp)) { + dns_rdataset_disassociate(*rdatasetp); + } + dns_db_detachnode(*dbp, nodep); + + if (qtype == dns_rdatatype_rrsig || + qtype == dns_rdatatype_sig) + { + result = DNS_R_NXRRSET; + } else { + result = dns_db_findext(*dbp, p_name, *versionp, + qtype, 0, client->now, + nodep, found, &cm, &ci, + *rdatasetp, NULL); + } + } + } + switch (result) { + case ISC_R_SUCCESS: + if ((*rdatasetp)->type != dns_rdatatype_cname) { + *policyp = DNS_RPZ_POLICY_RECORD; + } else { + *policyp = dns_rpz_decode_cname(rpz, *rdatasetp, + self_name); + if ((*policyp == DNS_RPZ_POLICY_RECORD || + *policyp == DNS_RPZ_POLICY_WILDCNAME) && + qtype != dns_rdatatype_cname && + qtype != dns_rdatatype_any) + { + return (DNS_R_CNAME); + } + } + return (ISC_R_SUCCESS); + case DNS_R_NXRRSET: + if (found_a) { + *policyp = DNS_RPZ_POLICY_DNS64; + } else { + *policyp = DNS_RPZ_POLICY_NODATA; + } + return (result); + case DNS_R_DNAME: + /* + * DNAME policy RRs have very few if any uses that are not + * better served with simple wildcards. Making them work would + * require complications to get the number of labels matched + * in the name or the found name to the main DNS_R_DNAME case + * in query_dname(). The domain also does not appear in the + * summary database at the right level, so this happens only + * with a single policy zone when we have no summary database. + * Treat it as a miss. + */ + case DNS_R_NXDOMAIN: + case DNS_R_EMPTYNAME: + return (DNS_R_NXDOMAIN); + default: + rpz_log_fail(client, DNS_RPZ_ERROR_LEVEL, p_name, rpz_type, "", + result); + CTRACE(ISC_LOG_ERROR, "rpz_find_p: unexpected result"); + return (DNS_R_SERVFAIL); + } +} + +static void +rpz_save_p(dns_rpz_st_t *st, dns_rpz_zone_t *rpz, dns_rpz_type_t rpz_type, + dns_rpz_policy_t policy, dns_name_t *p_name, dns_rpz_prefix_t prefix, + isc_result_t result, dns_zone_t **zonep, dns_db_t **dbp, + dns_dbnode_t **nodep, dns_rdataset_t **rdatasetp, + dns_dbversion_t *version) { + dns_rdataset_t *trdataset = NULL; + + rpz_match_clear(st); + st->m.rpz = rpz; + st->m.type = rpz_type; + st->m.policy = policy; + dns_name_copy(p_name, st->p_name); + st->m.prefix = prefix; + st->m.result = result; + SAVE(st->m.zone, *zonep); + SAVE(st->m.db, *dbp); + SAVE(st->m.node, *nodep); + if (*rdatasetp != NULL && dns_rdataset_isassociated(*rdatasetp)) { + /* + * Save the replacement rdataset from the policy + * and make the previous replacement rdataset scratch. + */ + SAVE(trdataset, st->m.rdataset); + SAVE(st->m.rdataset, *rdatasetp); + SAVE(*rdatasetp, trdataset); + st->m.ttl = ISC_MIN(st->m.rdataset->ttl, rpz->max_policy_ttl); + } else { + st->m.ttl = ISC_MIN(DNS_RPZ_TTL_DEFAULT, rpz->max_policy_ttl); + } + SAVE(st->m.version, version); +} + +#ifdef USE_DNSRPS +/* + * Check the results of a RPZ service interface lookup. + * Stop after an error (<0) or not a hit on a disabled zone (0). + * Continue after a hit on a disabled zone (>0). + */ +static int +dnsrps_ck(librpz_emsg_t *emsg, ns_client_t *client, rpsdb_t *rpsdb, + bool recursed) { + isc_region_t region; + librpz_domain_buf_t pname_buf; + + if (!librpz->rsp_result(emsg, &rpsdb->result, recursed, rpsdb->rsp)) { + return (-1); + } + + /* + * Forget the state from before the IP address or domain check + * if the lookup hit nothing. + */ + if (rpsdb->result.policy == LIBRPZ_POLICY_UNDEFINED || + rpsdb->result.hit_id != rpsdb->hit_id || + rpsdb->result.policy != LIBRPZ_POLICY_DISABLED) + { + if (!librpz->rsp_pop_discard(emsg, rpsdb->rsp)) { + return (-1); + } + return (0); + } + + /* + * Log a hit on a disabled zone. + * Forget the zone to not try it again, and restore the pre-hit state. + */ + if (!librpz->rsp_domain(emsg, &pname_buf, rpsdb->rsp)) { + return (-1); + } + region.base = pname_buf.d; + region.length = pname_buf.size; + dns_name_fromregion(client->query.rpz_st->p_name, ®ion); + rpz_log_rewrite(client, true, dns_dnsrps_2policy(rpsdb->result.zpolicy), + dns_dnsrps_trig2type(rpsdb->result.trig), NULL, + client->query.rpz_st->p_name, NULL, + rpsdb->result.cznum); + + if (!librpz->rsp_forget_zone(emsg, rpsdb->result.cznum, rpsdb->rsp) || + !librpz->rsp_pop(emsg, &rpsdb->result, rpsdb->rsp)) + { + return (-1); + } + return (1); +} + +/* + * Ready the shim database and rdataset for a DNSRPS hit. + */ +static bool +dnsrps_set_p(librpz_emsg_t *emsg, ns_client_t *client, dns_rpz_st_t *st, + dns_rdatatype_t qtype, dns_rdataset_t **p_rdatasetp, + bool recursed) { + rpsdb_t *rpsdb; + librpz_domain_buf_t pname_buf; + isc_region_t region; + dns_zone_t *p_zone; + dns_db_t *p_db; + dns_dbnode_t *p_node; + dns_rpz_policy_t policy; + dns_fixedname_t foundf; + dns_name_t *found; + dns_rdatatype_t foundtype, searchtype; + isc_result_t result; + + rpsdb = (rpsdb_t *)st->rpsdb; + + if (!librpz->rsp_result(emsg, &rpsdb->result, recursed, rpsdb->rsp)) { + return (false); + } + + if (rpsdb->result.policy == LIBRPZ_POLICY_UNDEFINED) { + return (true); + } + + /* + * Give the fake or shim DNSRPS database its new origin. + */ + if (!librpz->rsp_soa(emsg, NULL, NULL, &rpsdb->origin_buf, + &rpsdb->result, rpsdb->rsp)) + { + return (false); + } + region.base = rpsdb->origin_buf.d; + region.length = rpsdb->origin_buf.size; + dns_name_fromregion(&rpsdb->common.origin, ®ion); + + if (!librpz->rsp_domain(emsg, &pname_buf, rpsdb->rsp)) { + return (false); + } + region.base = pname_buf.d; + region.length = pname_buf.size; + dns_name_fromregion(st->p_name, ®ion); + + p_zone = NULL; + p_db = NULL; + p_node = NULL; + rpz_ready(client, p_rdatasetp); + dns_db_attach(st->rpsdb, &p_db); + policy = dns_dnsrps_2policy(rpsdb->result.policy); + if (policy != DNS_RPZ_POLICY_RECORD) { + result = ISC_R_SUCCESS; + } else if (qtype == dns_rdatatype_rrsig) { + /* + * dns_find_db() refuses to look for and fail to + * find dns_rdatatype_rrsig. + */ + result = DNS_R_NXRRSET; + policy = DNS_RPZ_POLICY_NODATA; + } else { + /* + * Get the next (and so first) RR from the policy node. + * If it is a CNAME, then look for it regardless of the + * query type. + */ + if (!librpz->rsp_rr(emsg, &foundtype, NULL, NULL, NULL, + &rpsdb->result, rpsdb->qname->ndata, + rpsdb->qname->length, rpsdb->rsp)) + { + return (false); + } + if (foundtype == dns_rdatatype_cname) { + searchtype = dns_rdatatype_cname; + } else { + searchtype = qtype; + } + /* + * Get the DNSPRS imitation rdataset. + */ + found = dns_fixedname_initname(&foundf); + result = dns_db_find(p_db, st->p_name, NULL, searchtype, 0, 0, + &p_node, found, *p_rdatasetp, NULL); + + if (result == ISC_R_SUCCESS) { + if (searchtype == dns_rdatatype_cname && + qtype != dns_rdatatype_cname) + { + result = DNS_R_CNAME; + } + } else if (result == DNS_R_NXRRSET) { + policy = DNS_RPZ_POLICY_NODATA; + } else { + snprintf(emsg->c, sizeof(emsg->c), "dns_db_find(): %s", + isc_result_totext(result)); + return (false); + } + } + + rpz_save_p(st, client->view->rpzs->zones[rpsdb->result.cznum], + dns_dnsrps_trig2type(rpsdb->result.trig), policy, st->p_name, + 0, result, &p_zone, &p_db, &p_node, p_rdatasetp, NULL); + + rpz_clean(NULL, NULL, NULL, p_rdatasetp); + + return (true); +} + +static isc_result_t +dnsrps_rewrite_ip(ns_client_t *client, const isc_netaddr_t *netaddr, + dns_rpz_type_t rpz_type, dns_rdataset_t **p_rdatasetp) { + dns_rpz_st_t *st; + rpsdb_t *rpsdb; + librpz_trig_t trig = LIBRPZ_TRIG_CLIENT_IP; + bool recursed = false; + int res; + librpz_emsg_t emsg; + isc_result_t result; + + st = client->query.rpz_st; + rpsdb = (rpsdb_t *)st->rpsdb; + + result = rpz_ready(client, p_rdatasetp); + if (result != ISC_R_SUCCESS) { + st->m.policy = DNS_RPZ_POLICY_ERROR; + return (result); + } + + switch (rpz_type) { + case DNS_RPZ_TYPE_CLIENT_IP: + trig = LIBRPZ_TRIG_CLIENT_IP; + recursed = false; + break; + case DNS_RPZ_TYPE_IP: + trig = LIBRPZ_TRIG_IP; + recursed = true; + break; + case DNS_RPZ_TYPE_NSIP: + trig = LIBRPZ_TRIG_NSIP; + recursed = true; + break; + default: + UNREACHABLE(); + } + + do { + if (!librpz->rsp_push(&emsg, rpsdb->rsp) || + !librpz->ck_ip(&emsg, + netaddr->family == AF_INET + ? (const void *)&netaddr->type.in + : (const void *)&netaddr->type.in6, + netaddr->family, trig, ++rpsdb->hit_id, + recursed, rpsdb->rsp) || + (res = dnsrps_ck(&emsg, client, rpsdb, recursed)) < 0) + { + rpz_log_fail(client, DNS_RPZ_ERROR_LEVEL, NULL, + rpz_type, emsg.c, DNS_R_SERVFAIL); + st->m.policy = DNS_RPZ_POLICY_ERROR; + return (DNS_R_SERVFAIL); + } + } while (res != 0); + return (ISC_R_SUCCESS); +} + +static isc_result_t +dnsrps_rewrite_name(ns_client_t *client, dns_name_t *trig_name, bool recursed, + dns_rpz_type_t rpz_type, dns_rdataset_t **p_rdatasetp) { + dns_rpz_st_t *st; + rpsdb_t *rpsdb; + librpz_trig_t trig = LIBRPZ_TRIG_CLIENT_IP; + isc_region_t r; + int res; + librpz_emsg_t emsg; + isc_result_t result; + + st = client->query.rpz_st; + rpsdb = (rpsdb_t *)st->rpsdb; + + result = rpz_ready(client, p_rdatasetp); + if (result != ISC_R_SUCCESS) { + st->m.policy = DNS_RPZ_POLICY_ERROR; + return (result); + } + + switch (rpz_type) { + case DNS_RPZ_TYPE_QNAME: + trig = LIBRPZ_TRIG_QNAME; + break; + case DNS_RPZ_TYPE_NSDNAME: + trig = LIBRPZ_TRIG_NSDNAME; + break; + default: + UNREACHABLE(); + } + + dns_name_toregion(trig_name, &r); + do { + if (!librpz->rsp_push(&emsg, rpsdb->rsp) || + !librpz->ck_domain(&emsg, r.base, r.length, trig, + ++rpsdb->hit_id, recursed, rpsdb->rsp) || + (res = dnsrps_ck(&emsg, client, rpsdb, recursed)) < 0) + { + rpz_log_fail(client, DNS_RPZ_ERROR_LEVEL, NULL, + rpz_type, emsg.c, DNS_R_SERVFAIL); + st->m.policy = DNS_RPZ_POLICY_ERROR; + return (DNS_R_SERVFAIL); + } + } while (res != 0); + return (ISC_R_SUCCESS); +} +#endif /* USE_DNSRPS */ + +/* + * Check this address in every eligible policy zone. + */ +static isc_result_t +rpz_rewrite_ip(ns_client_t *client, const isc_netaddr_t *netaddr, + dns_rdatatype_t qtype, dns_rpz_type_t rpz_type, + dns_rpz_zbits_t zbits, dns_rdataset_t **p_rdatasetp) { + dns_rpz_zones_t *rpzs; + dns_rpz_st_t *st; + dns_rpz_zone_t *rpz; + dns_rpz_prefix_t prefix; + dns_rpz_num_t rpz_num; + dns_fixedname_t ip_namef, p_namef; + dns_name_t *ip_name, *p_name; + dns_zone_t *p_zone; + dns_db_t *p_db; + dns_dbversion_t *p_version; + dns_dbnode_t *p_node; + dns_rpz_policy_t policy; + isc_result_t result; + + CTRACE(ISC_LOG_DEBUG(3), "rpz_rewrite_ip"); + + rpzs = client->view->rpzs; + st = client->query.rpz_st; +#ifdef USE_DNSRPS + if (st->popt.dnsrps_enabled) { + return (dnsrps_rewrite_ip(client, netaddr, rpz_type, + p_rdatasetp)); + } +#endif /* ifdef USE_DNSRPS */ + + ip_name = dns_fixedname_initname(&ip_namef); + + p_zone = NULL; + p_db = NULL; + p_node = NULL; + + while (zbits != 0) { + rpz_num = dns_rpz_find_ip(rpzs, rpz_type, zbits, netaddr, + ip_name, &prefix); + if (rpz_num == DNS_RPZ_INVALID_NUM) { + break; + } + zbits &= (DNS_RPZ_ZMASK(rpz_num) >> 1); + + /* + * Do not try applying policy zones that cannot replace a + * previously found policy zone. + * Stop looking if the next best choice cannot + * replace what we already have. + */ + rpz = rpzs->zones[rpz_num]; + if (st->m.policy != DNS_RPZ_POLICY_MISS) { + if (st->m.rpz->num < rpz->num) { + break; + } + if (st->m.rpz->num == rpz->num && + (st->m.type < rpz_type || st->m.prefix > prefix)) + { + break; + } + } + + /* + * Get the policy for a prefix at least as long + * as the prefix of the entry we had before. + */ + p_name = dns_fixedname_initname(&p_namef); + result = rpz_get_p_name(client, p_name, rpz, rpz_type, ip_name); + if (result != ISC_R_SUCCESS) { + continue; + } + result = rpz_find_p(client, ip_name, qtype, p_name, rpz, + rpz_type, &p_zone, &p_db, &p_version, + &p_node, p_rdatasetp, &policy); + switch (result) { + case DNS_R_NXDOMAIN: + /* + * Continue after a policy record that is missing + * contrary to the summary data. The summary + * data can out of date during races with and among + * policy zone updates. + */ + CTRACE(ISC_LOG_ERROR, "rpz_rewrite_ip: mismatched " + "summary data; " + "continuing"); + continue; + case DNS_R_SERVFAIL: + rpz_clean(&p_zone, &p_db, &p_node, p_rdatasetp); + st->m.policy = DNS_RPZ_POLICY_ERROR; + return (DNS_R_SERVFAIL); + default: + /* + * Forget this policy if it is not preferable + * to the previously found policy. + * If this policy is not good, then stop looking + * because none of the later policy zones would work. + * + * With more than one applicable policy, prefer + * the earliest configured policy, + * client-IP over QNAME over IP over NSDNAME over NSIP, + * the longest prefix + * the lexically smallest address. + * dns_rpz_find_ip() ensures st->m.rpz->num >= rpz->num. + * We can compare new and current p_name because + * both are of the same type and in the same zone. + * The tests above eliminate other reasons to + * reject this policy. If this policy can't work, + * then neither can later zones. + */ + if (st->m.policy != DNS_RPZ_POLICY_MISS && + rpz->num == st->m.rpz->num && + (st->m.type == rpz_type && st->m.prefix == prefix && + 0 > dns_name_rdatacompare(st->p_name, p_name))) + { + break; + } + + /* + * Stop checking after saving an enabled hit in this + * policy zone. The radix tree in the policy zone + * ensures that we found the longest match. + */ + if (rpz->policy != DNS_RPZ_POLICY_DISABLED) { + CTRACE(ISC_LOG_DEBUG(3), "rpz_rewrite_ip: " + "rpz_save_p"); + rpz_save_p(st, rpz, rpz_type, policy, p_name, + prefix, result, &p_zone, &p_db, + &p_node, p_rdatasetp, p_version); + break; + } + + /* + * Log DNS_RPZ_POLICY_DISABLED zones + * and try the next eligible policy zone. + */ + rpz_log_rewrite(client, true, policy, rpz_type, p_zone, + p_name, NULL, rpz_num); + } + } + + rpz_clean(&p_zone, &p_db, &p_node, p_rdatasetp); + return (ISC_R_SUCCESS); +} + +/* + * Check the IP addresses in the A or AAAA rrsets for name against + * all eligible rpz_type (IP or NSIP) response policy rewrite rules. + */ +static isc_result_t +rpz_rewrite_ip_rrset(ns_client_t *client, dns_name_t *name, + dns_rdatatype_t qtype, dns_rpz_type_t rpz_type, + dns_rdatatype_t ip_type, dns_db_t **ip_dbp, + dns_dbversion_t *ip_version, dns_rdataset_t **ip_rdatasetp, + dns_rdataset_t **p_rdatasetp, bool resuming) { + dns_rpz_zbits_t zbits; + isc_netaddr_t netaddr; + struct in_addr ina; + struct in6_addr in6a; + isc_result_t result; + unsigned int options = client->query.dboptions | DNS_DBFIND_GLUEOK; + bool done = false; + + CTRACE(ISC_LOG_DEBUG(3), "rpz_rewrite_ip_rrset"); + + do { + zbits = rpz_get_zbits(client, ip_type, rpz_type); + if (zbits == 0) { + return (ISC_R_SUCCESS); + } + + /* + * Get the A or AAAA rdataset. + */ + result = rpz_rrset_find(client, name, ip_type, options, + rpz_type, ip_dbp, ip_version, + ip_rdatasetp, resuming); + switch (result) { + case ISC_R_SUCCESS: + case DNS_R_GLUE: + case DNS_R_ZONECUT: + break; + case DNS_R_EMPTYNAME: + case DNS_R_EMPTYWILD: + case DNS_R_NXDOMAIN: + case DNS_R_NCACHENXDOMAIN: + case DNS_R_NXRRSET: + case DNS_R_NCACHENXRRSET: + case ISC_R_NOTFOUND: + return (ISC_R_SUCCESS); + case DNS_R_DELEGATION: + case DNS_R_DUPLICATE: + case DNS_R_DROP: + return (result); + case DNS_R_CNAME: + case DNS_R_DNAME: + rpz_log_fail(client, DNS_RPZ_DEBUG_LEVEL1, name, + rpz_type, "NS address rewrite rrset", + result); + return (ISC_R_SUCCESS); + default: + if (client->query.rpz_st->m.policy != + DNS_RPZ_POLICY_ERROR) + { + client->query.rpz_st->m.policy = + DNS_RPZ_POLICY_ERROR; + rpz_log_fail(client, DNS_RPZ_ERROR_LEVEL, name, + rpz_type, + "NS address rewrite rrset", + result); + } + CTRACE(ISC_LOG_ERROR, + "rpz_rewrite_ip_rrset: unexpected " + "result"); + return (DNS_R_SERVFAIL); + } + + /* + * If we are processing glue setup for the next loop + * otherwise we are done. + */ + if (result == DNS_R_GLUE) { + options = client->query.dboptions; + } else { + options = client->query.dboptions | DNS_DBFIND_GLUEOK; + done = true; + } + + /* + * Check all of the IP addresses in the rdataset. + */ + for (result = dns_rdataset_first(*ip_rdatasetp); + result == ISC_R_SUCCESS; + result = dns_rdataset_next(*ip_rdatasetp)) + { + dns_rdata_t rdata = DNS_RDATA_INIT; + dns_rdataset_current(*ip_rdatasetp, &rdata); + switch (rdata.type) { + case dns_rdatatype_a: + INSIST(rdata.length == 4); + memmove(&ina.s_addr, rdata.data, 4); + isc_netaddr_fromin(&netaddr, &ina); + break; + case dns_rdatatype_aaaa: + INSIST(rdata.length == 16); + memmove(in6a.s6_addr, rdata.data, 16); + isc_netaddr_fromin6(&netaddr, &in6a); + break; + default: + continue; + } + + result = rpz_rewrite_ip(client, &netaddr, qtype, + rpz_type, zbits, p_rdatasetp); + if (result != ISC_R_SUCCESS) { + return (result); + } + } + } while (!done && + client->query.rpz_st->m.policy == DNS_RPZ_POLICY_MISS); + + return (ISC_R_SUCCESS); +} + +/* + * Look for IP addresses in A and AAAA rdatasets + * that trigger all eligible IP or NSIP policy rules. + */ +static isc_result_t +rpz_rewrite_ip_rrsets(ns_client_t *client, dns_name_t *name, + dns_rdatatype_t qtype, dns_rpz_type_t rpz_type, + dns_rdataset_t **ip_rdatasetp, bool resuming) { + dns_rpz_st_t *st; + dns_dbversion_t *ip_version; + dns_db_t *ip_db; + dns_rdataset_t *p_rdataset; + isc_result_t result; + + CTRACE(ISC_LOG_DEBUG(3), "rpz_rewrite_ip_rrsets"); + + st = client->query.rpz_st; + ip_version = NULL; + ip_db = NULL; + p_rdataset = NULL; + if ((st->state & DNS_RPZ_DONE_IPv4) == 0 && + (qtype == dns_rdatatype_a || qtype == dns_rdatatype_any || + rpz_type == DNS_RPZ_TYPE_NSIP)) + { + /* + * Rewrite based on an IPv4 address that will appear + * in the ANSWER section or if we are checking IP addresses. + */ + result = rpz_rewrite_ip_rrset( + client, name, qtype, rpz_type, dns_rdatatype_a, &ip_db, + ip_version, ip_rdatasetp, &p_rdataset, resuming); + if (result == ISC_R_SUCCESS) { + st->state |= DNS_RPZ_DONE_IPv4; + } + } else { + result = ISC_R_SUCCESS; + } + if (result == ISC_R_SUCCESS && + (qtype == dns_rdatatype_aaaa || qtype == dns_rdatatype_any || + rpz_type == DNS_RPZ_TYPE_NSIP)) + { + /* + * Rewrite based on IPv6 addresses that will appear + * in the ANSWER section or if we are checking IP addresses. + */ + result = rpz_rewrite_ip_rrset(client, name, qtype, rpz_type, + dns_rdatatype_aaaa, &ip_db, + ip_version, ip_rdatasetp, + &p_rdataset, resuming); + } + if (ip_db != NULL) { + dns_db_detach(&ip_db); + } + ns_client_putrdataset(client, &p_rdataset); + return (result); +} + +/* + * Try to rewrite a request for a qtype rdataset based on the trigger name + * trig_name and rpz_type (DNS_RPZ_TYPE_QNAME or DNS_RPZ_TYPE_NSDNAME). + * Record the results including the replacement rdataset if any + * in client->query.rpz_st. + * *rdatasetp is a scratch rdataset. + */ +static isc_result_t +rpz_rewrite_name(ns_client_t *client, dns_name_t *trig_name, + dns_rdatatype_t qtype, dns_rpz_type_t rpz_type, + dns_rpz_zbits_t allowed_zbits, bool recursed, + dns_rdataset_t **rdatasetp) { + dns_rpz_zones_t *rpzs; + dns_rpz_zone_t *rpz; + dns_rpz_st_t *st; + dns_fixedname_t p_namef; + dns_name_t *p_name; + dns_rpz_zbits_t zbits; + dns_rpz_num_t rpz_num; + dns_zone_t *p_zone; + dns_db_t *p_db; + dns_dbversion_t *p_version; + dns_dbnode_t *p_node; + dns_rpz_policy_t policy; + isc_result_t result; + +#ifndef USE_DNSRPS + UNUSED(recursed); +#endif /* ifndef USE_DNSRPS */ + + CTRACE(ISC_LOG_DEBUG(3), "rpz_rewrite_name"); + + rpzs = client->view->rpzs; + st = client->query.rpz_st; + +#ifdef USE_DNSRPS + if (st->popt.dnsrps_enabled) { + return (dnsrps_rewrite_name(client, trig_name, recursed, + rpz_type, rdatasetp)); + } +#endif /* ifdef USE_DNSRPS */ + + zbits = rpz_get_zbits(client, qtype, rpz_type); + zbits &= allowed_zbits; + if (zbits == 0) { + return (ISC_R_SUCCESS); + } + + /* + * Use the summary database to find the bit mask of policy zones + * with policies for this trigger name. We do this even if there + * is only one eligible policy zone so that wildcard triggers + * are matched correctly, and not into their parent. + */ + zbits = dns_rpz_find_name(rpzs, rpz_type, zbits, trig_name); + if (zbits == 0) { + return (ISC_R_SUCCESS); + } + + p_name = dns_fixedname_initname(&p_namef); + + p_zone = NULL; + p_db = NULL; + p_node = NULL; + + /* + * Check the trigger name in every policy zone that the summary data + * says has a hit for the trigger name. + * Most of the time there are no eligible zones and the summary data + * keeps us from getting this far. + * We check the most eligible zone first and so usually check only + * one policy zone. + */ + for (rpz_num = 0; zbits != 0; ++rpz_num, zbits >>= 1) { + if ((zbits & 1) == 0) { + continue; + } + + /* + * Do not check policy zones that cannot replace a previously + * found policy. + */ + rpz = rpzs->zones[rpz_num]; + if (st->m.policy != DNS_RPZ_POLICY_MISS) { + if (st->m.rpz->num < rpz->num) { + break; + } + if (st->m.rpz->num == rpz->num && st->m.type < rpz_type) + { + break; + } + } + + /* + * Get the next policy zone's record for this trigger name. + */ + result = rpz_get_p_name(client, p_name, rpz, rpz_type, + trig_name); + if (result != ISC_R_SUCCESS) { + continue; + } + result = rpz_find_p(client, trig_name, qtype, p_name, rpz, + rpz_type, &p_zone, &p_db, &p_version, + &p_node, rdatasetp, &policy); + switch (result) { + case DNS_R_NXDOMAIN: + /* + * Continue after a missing policy record + * contrary to the summary data. The summary + * data can out of date during races with and among + * policy zone updates. + */ + CTRACE(ISC_LOG_ERROR, "rpz_rewrite_name: mismatched " + "summary data; " + "continuing"); + continue; + case DNS_R_SERVFAIL: + rpz_clean(&p_zone, &p_db, &p_node, rdatasetp); + st->m.policy = DNS_RPZ_POLICY_ERROR; + return (DNS_R_SERVFAIL); + default: + /* + * With more than one applicable policy, prefer + * the earliest configured policy, + * client-IP over QNAME over IP over NSDNAME over NSIP, + * and the smallest name. + * We known st->m.rpz->num >= rpz->num and either + * st->m.rpz->num > rpz->num or st->m.type >= rpz_type + */ + if (st->m.policy != DNS_RPZ_POLICY_MISS && + rpz->num == st->m.rpz->num && + (st->m.type < rpz_type || + (st->m.type == rpz_type && + 0 >= dns_name_compare(p_name, st->p_name)))) + { + continue; + } + + if (rpz->policy != DNS_RPZ_POLICY_DISABLED) { + CTRACE(ISC_LOG_DEBUG(3), "rpz_rewrite_name: " + "rpz_save_p"); + rpz_save_p(st, rpz, rpz_type, policy, p_name, 0, + result, &p_zone, &p_db, &p_node, + rdatasetp, p_version); + /* + * After a hit, higher numbered policy zones + * are irrelevant + */ + rpz_clean(&p_zone, &p_db, &p_node, rdatasetp); + return (ISC_R_SUCCESS); + } + /* + * Log DNS_RPZ_POLICY_DISABLED zones + * and try the next eligible policy zone. + */ + rpz_log_rewrite(client, true, policy, rpz_type, p_zone, + p_name, NULL, rpz_num); + break; + } + } + + rpz_clean(&p_zone, &p_db, &p_node, rdatasetp); + return (ISC_R_SUCCESS); +} + +static void +rpz_rewrite_ns_skip(ns_client_t *client, dns_name_t *nsname, + isc_result_t result, int level, const char *str) { + dns_rpz_st_t *st; + + CTRACE(ISC_LOG_DEBUG(3), "rpz_rewrite_ns_skip"); + + st = client->query.rpz_st; + + if (str != NULL) { + rpz_log_fail_helper(client, level, nsname, DNS_RPZ_TYPE_NSIP, + DNS_RPZ_TYPE_NSDNAME, str, result); + } + if (st->r.ns_rdataset != NULL && + dns_rdataset_isassociated(st->r.ns_rdataset)) + { + dns_rdataset_disassociate(st->r.ns_rdataset); + } + + st->r.label--; +} + +/* + * RPZ query result types + */ +typedef enum { + qresult_type_done = 0, + qresult_type_restart = 1, + qresult_type_recurse = 2 +} qresult_type_t; + +/* + * Look for response policy zone QNAME, NSIP, and NSDNAME rewriting. + */ +static isc_result_t +rpz_rewrite(ns_client_t *client, dns_rdatatype_t qtype, isc_result_t qresult, + bool resuming, dns_rdataset_t *ordataset, dns_rdataset_t *osigset) { + dns_rpz_zones_t *rpzs; + dns_rpz_st_t *st; + dns_rdataset_t *rdataset; + dns_fixedname_t nsnamef; + dns_name_t *nsname; + qresult_type_t qresult_type; + dns_rpz_zbits_t zbits; + isc_result_t result = ISC_R_SUCCESS; + dns_rpz_have_t have; + dns_rpz_popt_t popt; + int rpz_ver; + unsigned int options; +#ifdef USE_DNSRPS + librpz_emsg_t emsg; +#endif /* ifdef USE_DNSRPS */ + + CTRACE(ISC_LOG_DEBUG(3), "rpz_rewrite"); + + rpzs = client->view->rpzs; + st = client->query.rpz_st; + + if (rpzs == NULL) { + return (ISC_R_NOTFOUND); + } + if (st != NULL && (st->state & DNS_RPZ_REWRITTEN) != 0) { + return (DNS_R_DISALLOWED); + } + if (RECURSING(client)) { + return (DNS_R_DISALLOWED); + } + + RWLOCK(&rpzs->search_lock, isc_rwlocktype_read); + if ((rpzs->p.num_zones == 0 && !rpzs->p.dnsrps_enabled) || + (!RECURSIONOK(client) && rpzs->p.no_rd_ok == 0) || + !rpz_ck_dnssec(client, qresult, ordataset, osigset)) + { + RWUNLOCK(&rpzs->search_lock, isc_rwlocktype_read); + return (DNS_R_DISALLOWED); + } + have = rpzs->have; + popt = rpzs->p; + rpz_ver = rpzs->rpz_ver; + RWUNLOCK(&rpzs->search_lock, isc_rwlocktype_read); + +#ifndef USE_DNSRPS + INSIST(!popt.dnsrps_enabled); +#endif /* ifndef USE_DNSRPS */ + + if (st == NULL) { + st = isc_mem_get(client->mctx, sizeof(*st)); + st->state = 0; + st->rpsdb = NULL; + } + if (st->state == 0) { + st->state |= DNS_RPZ_ACTIVE; + memset(&st->m, 0, sizeof(st->m)); + st->m.type = DNS_RPZ_TYPE_BAD; + st->m.policy = DNS_RPZ_POLICY_MISS; + st->m.ttl = ~0; + memset(&st->r, 0, sizeof(st->r)); + memset(&st->q, 0, sizeof(st->q)); + st->p_name = dns_fixedname_initname(&st->_p_namef); + st->r_name = dns_fixedname_initname(&st->_r_namef); + st->fname = dns_fixedname_initname(&st->_fnamef); + st->have = have; + st->popt = popt; + st->rpz_ver = rpz_ver; + client->query.rpz_st = st; +#ifdef USE_DNSRPS + if (popt.dnsrps_enabled) { + if (st->rpsdb != NULL) { + dns_db_detach(&st->rpsdb); + } + result = dns_dnsrps_rewrite_init( + &emsg, st, rpzs, client->query.qname, + client->mctx, RECURSIONOK(client)); + if (result != ISC_R_SUCCESS) { + rpz_log_fail(client, DNS_RPZ_ERROR_LEVEL, NULL, + DNS_RPZ_TYPE_QNAME, emsg.c, + result); + st->m.policy = DNS_RPZ_POLICY_ERROR; + return (ISC_R_SUCCESS); + } + } +#endif /* ifdef USE_DNSRPS */ + } + + /* + * There is nothing to rewrite if the main query failed. + */ + switch (qresult) { + case ISC_R_SUCCESS: + case DNS_R_GLUE: + case DNS_R_ZONECUT: + qresult_type = qresult_type_done; + break; + case DNS_R_EMPTYNAME: + case DNS_R_NXRRSET: + case DNS_R_NXDOMAIN: + case DNS_R_EMPTYWILD: + case DNS_R_NCACHENXDOMAIN: + case DNS_R_NCACHENXRRSET: + case DNS_R_COVERINGNSEC: + case DNS_R_CNAME: + case DNS_R_DNAME: + qresult_type = qresult_type_restart; + break; + case DNS_R_DELEGATION: + case ISC_R_NOTFOUND: + /* + * If recursion is on, do only tentative rewriting. + * If recursion is off, this the normal and only time we + * can rewrite. + */ + if (RECURSIONOK(client)) { + qresult_type = qresult_type_recurse; + } else { + qresult_type = qresult_type_restart; + } + break; + case ISC_R_FAILURE: + case ISC_R_TIMEDOUT: + case DNS_R_BROKENCHAIN: + rpz_log_fail(client, DNS_RPZ_DEBUG_LEVEL3, NULL, + DNS_RPZ_TYPE_QNAME, + "stop on qresult in rpz_rewrite()", qresult); + return (ISC_R_SUCCESS); + default: + rpz_log_fail(client, DNS_RPZ_DEBUG_LEVEL1, NULL, + DNS_RPZ_TYPE_QNAME, + "stop on unrecognized qresult in rpz_rewrite()", + qresult); + return (ISC_R_SUCCESS); + } + + rdataset = NULL; + + if ((st->state & (DNS_RPZ_DONE_CLIENT_IP | DNS_RPZ_DONE_QNAME)) != + (DNS_RPZ_DONE_CLIENT_IP | DNS_RPZ_DONE_QNAME)) + { + isc_netaddr_t netaddr; + dns_rpz_zbits_t allowed; + + if (!st->popt.dnsrps_enabled && + qresult_type == qresult_type_recurse) + { + /* + * This request needs recursion that has not been done. + * Get bits for the policy zones that do not need + * to wait for the results of recursion. + */ + allowed = st->have.qname_skip_recurse; + if (allowed == 0) { + return (ISC_R_SUCCESS); + } + } else { + allowed = DNS_RPZ_ALL_ZBITS; + } + + /* + * Check once for triggers for the client IP address. + */ + if ((st->state & DNS_RPZ_DONE_CLIENT_IP) == 0) { + zbits = rpz_get_zbits(client, dns_rdatatype_none, + DNS_RPZ_TYPE_CLIENT_IP); + zbits &= allowed; + if (zbits != 0) { + isc_netaddr_fromsockaddr(&netaddr, + &client->peeraddr); + result = rpz_rewrite_ip(client, &netaddr, qtype, + DNS_RPZ_TYPE_CLIENT_IP, + zbits, &rdataset); + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + } + } + + /* + * Check triggers for the query name if this is the first time + * for the current qname. + * There is a first time for each name in a CNAME chain + */ + if ((st->state & DNS_RPZ_DONE_QNAME) == 0) { + bool norec = (qresult_type != qresult_type_recurse); + result = rpz_rewrite_name(client, client->query.qname, + qtype, DNS_RPZ_TYPE_QNAME, + allowed, norec, &rdataset); + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + + /* + * Check IPv4 addresses in A RRs next. + * Reset to the start of the NS names. + */ + st->r.label = dns_name_countlabels(client->query.qname); + st->state &= ~(DNS_RPZ_DONE_QNAME_IP | + DNS_RPZ_DONE_IPv4); + } + + /* + * Quit if this was an attempt to find a qname or + * client-IP trigger before recursion. + * We will be back if no pre-recursion triggers hit. + * For example, consider 2 policy zones, both with qname and + * IP address triggers. If the qname misses the 1st zone, + * then we cannot know whether a hit for the qname in the + * 2nd zone matters until after recursing to get the A RRs and + * testing them in the first zone. + * Do not bother saving the work from this attempt, + * because recursion is so slow. + */ + if (qresult_type == qresult_type_recurse) { + goto cleanup; + } + + /* + * DNS_RPZ_DONE_QNAME but not DNS_RPZ_DONE_CLIENT_IP + * is reset at the end of dealing with each CNAME. + */ + st->state |= (DNS_RPZ_DONE_CLIENT_IP | DNS_RPZ_DONE_QNAME); + } + + /* + * Check known IP addresses for the query name if the database lookup + * resulted in some addresses (qresult_type == qresult_type_done) + * and if we have not already checked them. + * Any recursion required for the query has already happened. + * Do not check addresses that will not be in the ANSWER section. + */ + if ((st->state & DNS_RPZ_DONE_QNAME_IP) == 0 && + qresult_type == qresult_type_done && + rpz_get_zbits(client, qtype, DNS_RPZ_TYPE_IP) != 0) + { + result = rpz_rewrite_ip_rrsets(client, client->query.qname, + qtype, DNS_RPZ_TYPE_IP, + &rdataset, resuming); + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + /* + * We are finished checking the IP addresses for the qname. + * Start with IPv4 if we will check NS IP addresses. + */ + st->state |= DNS_RPZ_DONE_QNAME_IP; + st->state &= ~DNS_RPZ_DONE_IPv4; + } + + /* + * Stop looking for rules if there are none of the other kinds + * that could override what we already have. + */ + if (rpz_get_zbits(client, dns_rdatatype_any, DNS_RPZ_TYPE_NSDNAME) == + 0 && + rpz_get_zbits(client, dns_rdatatype_any, DNS_RPZ_TYPE_NSIP) == 0) + { + result = ISC_R_SUCCESS; + goto cleanup; + } + + dns_fixedname_init(&nsnamef); + dns_name_clone(client->query.qname, dns_fixedname_name(&nsnamef)); + options = client->query.dboptions | DNS_DBFIND_GLUEOK; + while (st->r.label > st->popt.min_ns_labels) { + bool was_glue = false; + /* + * Get NS rrset for each domain in the current qname. + */ + if (st->r.label == dns_name_countlabels(client->query.qname)) { + nsname = client->query.qname; + } else { + nsname = dns_fixedname_name(&nsnamef); + dns_name_split(client->query.qname, st->r.label, NULL, + nsname); + } + if (st->r.ns_rdataset == NULL || + !dns_rdataset_isassociated(st->r.ns_rdataset)) + { + dns_db_t *db = NULL; + result = rpz_rrset_find(client, nsname, + dns_rdatatype_ns, options, + DNS_RPZ_TYPE_NSDNAME, &db, NULL, + &st->r.ns_rdataset, resuming); + if (db != NULL) { + dns_db_detach(&db); + } + if (st->m.policy == DNS_RPZ_POLICY_ERROR) { + goto cleanup; + } + switch (result) { + case DNS_R_GLUE: + was_glue = true; + FALLTHROUGH; + case ISC_R_SUCCESS: + result = dns_rdataset_first(st->r.ns_rdataset); + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + st->state &= ~(DNS_RPZ_DONE_NSDNAME | + DNS_RPZ_DONE_IPv4); + break; + case DNS_R_DELEGATION: + case DNS_R_DUPLICATE: + case DNS_R_DROP: + goto cleanup; + case DNS_R_EMPTYNAME: + case DNS_R_NXRRSET: + case DNS_R_EMPTYWILD: + case DNS_R_NXDOMAIN: + case DNS_R_NCACHENXDOMAIN: + case DNS_R_NCACHENXRRSET: + case ISC_R_NOTFOUND: + case DNS_R_CNAME: + case DNS_R_DNAME: + rpz_rewrite_ns_skip(client, nsname, result, 0, + NULL); + continue; + case ISC_R_TIMEDOUT: + case DNS_R_BROKENCHAIN: + case ISC_R_FAILURE: + rpz_rewrite_ns_skip(client, nsname, result, + DNS_RPZ_DEBUG_LEVEL3, + " NS rpz_rrset_find()"); + continue; + default: + rpz_rewrite_ns_skip(client, nsname, result, + DNS_RPZ_INFO_LEVEL, + " unrecognized NS" + " rpz_rrset_find()"); + continue; + } + } + + /* + * Check all NS names. + */ + do { + dns_rdata_ns_t ns; + dns_rdata_t nsrdata = DNS_RDATA_INIT; + + dns_rdataset_current(st->r.ns_rdataset, &nsrdata); + result = dns_rdata_tostruct(&nsrdata, &ns, NULL); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + dns_rdata_reset(&nsrdata); + + /* + * Do nothing about "NS ." + */ + if (dns_name_equal(&ns.name, dns_rootname)) { + dns_rdata_freestruct(&ns); + result = dns_rdataset_next(st->r.ns_rdataset); + continue; + } + /* + * Check this NS name if we did not handle it + * during a previous recursion. + */ + if ((st->state & DNS_RPZ_DONE_NSDNAME) == 0) { + result = rpz_rewrite_name( + client, &ns.name, qtype, + DNS_RPZ_TYPE_NSDNAME, DNS_RPZ_ALL_ZBITS, + true, &rdataset); + if (result != ISC_R_SUCCESS) { + dns_rdata_freestruct(&ns); + goto cleanup; + } + st->state |= DNS_RPZ_DONE_NSDNAME; + } + /* + * Check all IP addresses for this NS name. + */ + result = rpz_rewrite_ip_rrsets(client, &ns.name, qtype, + DNS_RPZ_TYPE_NSIP, + &rdataset, resuming); + dns_rdata_freestruct(&ns); + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + st->state &= ~(DNS_RPZ_DONE_NSDNAME | + DNS_RPZ_DONE_IPv4); + result = dns_rdataset_next(st->r.ns_rdataset); + } while (result == ISC_R_SUCCESS); + dns_rdataset_disassociate(st->r.ns_rdataset); + + /* + * If we just checked a glue NS RRset retry without allowing + * glue responses, otherwise setup for the next name. + */ + if (was_glue) { + options = client->query.dboptions; + } else { + options = client->query.dboptions | DNS_DBFIND_GLUEOK; + st->r.label--; + } + + if (rpz_get_zbits(client, dns_rdatatype_any, + DNS_RPZ_TYPE_NSDNAME) == 0 && + rpz_get_zbits(client, dns_rdatatype_any, + DNS_RPZ_TYPE_NSIP) == 0) + { + break; + } + } + + /* + * Use the best hit, if any. + */ + result = ISC_R_SUCCESS; + +cleanup: +#ifdef USE_DNSRPS + if (st->popt.dnsrps_enabled && st->m.policy != DNS_RPZ_POLICY_ERROR && + !dnsrps_set_p(&emsg, client, st, qtype, &rdataset, + (qresult_type != qresult_type_recurse))) + { + rpz_log_fail(client, DNS_RPZ_ERROR_LEVEL, NULL, + DNS_RPZ_TYPE_BAD, emsg.c, DNS_R_SERVFAIL); + st->m.policy = DNS_RPZ_POLICY_ERROR; + } +#endif /* ifdef USE_DNSRPS */ + if (st->m.policy != DNS_RPZ_POLICY_MISS && + st->m.policy != DNS_RPZ_POLICY_ERROR && + st->m.rpz->policy != DNS_RPZ_POLICY_GIVEN) + { + st->m.policy = st->m.rpz->policy; + } + if (st->m.policy == DNS_RPZ_POLICY_MISS || + st->m.policy == DNS_RPZ_POLICY_PASSTHRU || + st->m.policy == DNS_RPZ_POLICY_ERROR) + { + if (st->m.policy == DNS_RPZ_POLICY_PASSTHRU && + result != DNS_R_DELEGATION) + { + rpz_log_rewrite(client, false, st->m.policy, st->m.type, + st->m.zone, st->p_name, NULL, + st->m.rpz->num); + } + rpz_match_clear(st); + } + if (st->m.policy == DNS_RPZ_POLICY_ERROR) { + CTRACE(ISC_LOG_ERROR, "SERVFAIL due to RPZ policy"); + st->m.type = DNS_RPZ_TYPE_BAD; + result = DNS_R_SERVFAIL; + } + ns_client_putrdataset(client, &rdataset); + if ((st->state & DNS_RPZ_RECURSING) == 0) { + rpz_clean(NULL, &st->r.db, NULL, &st->r.ns_rdataset); + } + + return (result); +} + +/* + * See if response policy zone rewriting is allowed by a lack of interest + * by the client in DNSSEC or a lack of signatures. + */ +static bool +rpz_ck_dnssec(ns_client_t *client, isc_result_t qresult, + dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset) { + dns_fixedname_t fixed; + dns_name_t *found; + dns_rdataset_t trdataset; + dns_rdatatype_t type; + isc_result_t result; + + CTRACE(ISC_LOG_DEBUG(3), "rpz_ck_dnssec"); + + if (client->view->rpzs->p.break_dnssec || !WANTDNSSEC(client)) { + return (true); + } + + /* + * We do not know if there are signatures if we have not recursed + * for them. + */ + if (qresult == DNS_R_DELEGATION || qresult == ISC_R_NOTFOUND) { + return (false); + } + + if (sigrdataset == NULL) { + return (true); + } + if (dns_rdataset_isassociated(sigrdataset)) { + return (false); + } + + /* + * We are happy to rewrite nothing. + */ + if (rdataset == NULL || !dns_rdataset_isassociated(rdataset)) { + return (true); + } + /* + * Do not rewrite if there is any sign of signatures. + */ + if (rdataset->type == dns_rdatatype_nsec || + rdataset->type == dns_rdatatype_nsec3 || + rdataset->type == dns_rdatatype_rrsig) + { + return (false); + } + + /* + * Look for a signature in a negative cache rdataset. + */ + if ((rdataset->attributes & DNS_RDATASETATTR_NEGATIVE) == 0) { + return (true); + } + found = dns_fixedname_initname(&fixed); + dns_rdataset_init(&trdataset); + for (result = dns_rdataset_first(rdataset); result == ISC_R_SUCCESS; + result = dns_rdataset_next(rdataset)) + { + dns_ncache_current(rdataset, found, &trdataset); + type = trdataset.type; + dns_rdataset_disassociate(&trdataset); + if (type == dns_rdatatype_nsec || type == dns_rdatatype_nsec3 || + type == dns_rdatatype_rrsig) + { + return (false); + } + } + return (true); +} + +/* + * 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); + memmove(&ina.s_addr, rdata->data, 4); + isc_netaddr_fromin(netaddr, &ina); + return (ISC_R_SUCCESS); + case dns_rdatatype_aaaa: + INSIST(rdata->length == 16); + memmove(in6a.s6_addr, rdata->data, 16); + isc_netaddr_fromin6(netaddr, &in6a); + return (ISC_R_SUCCESS); + default: + return (ISC_R_NOTIMPLEMENTED); + } +} + +static unsigned char inaddr10_offsets[] = { 0, 3, 11, 16 }; +static unsigned char inaddr172_offsets[] = { 0, 3, 7, 15, 20 }; +static unsigned char inaddr192_offsets[] = { 0, 4, 8, 16, 21 }; + +static unsigned char inaddr10[] = "\00210\007IN-ADDR\004ARPA"; + +static unsigned char inaddr16172[] = "\00216\003172\007IN-ADDR\004ARPA"; +static unsigned char inaddr17172[] = "\00217\003172\007IN-ADDR\004ARPA"; +static unsigned char inaddr18172[] = "\00218\003172\007IN-ADDR\004ARPA"; +static unsigned char inaddr19172[] = "\00219\003172\007IN-ADDR\004ARPA"; +static unsigned char inaddr20172[] = "\00220\003172\007IN-ADDR\004ARPA"; +static unsigned char inaddr21172[] = "\00221\003172\007IN-ADDR\004ARPA"; +static unsigned char inaddr22172[] = "\00222\003172\007IN-ADDR\004ARPA"; +static unsigned char inaddr23172[] = "\00223\003172\007IN-ADDR\004ARPA"; +static unsigned char inaddr24172[] = "\00224\003172\007IN-ADDR\004ARPA"; +static unsigned char inaddr25172[] = "\00225\003172\007IN-ADDR\004ARPA"; +static unsigned char inaddr26172[] = "\00226\003172\007IN-ADDR\004ARPA"; +static unsigned char inaddr27172[] = "\00227\003172\007IN-ADDR\004ARPA"; +static unsigned char inaddr28172[] = "\00228\003172\007IN-ADDR\004ARPA"; +static unsigned char inaddr29172[] = "\00229\003172\007IN-ADDR\004ARPA"; +static unsigned char inaddr30172[] = "\00230\003172\007IN-ADDR\004ARPA"; +static unsigned char inaddr31172[] = "\00231\003172\007IN-ADDR\004ARPA"; + +static unsigned char inaddr168192[] = "\003168\003192\007IN-ADDR\004ARPA"; + +static dns_name_t rfc1918names[] = { + DNS_NAME_INITABSOLUTE(inaddr10, inaddr10_offsets), + DNS_NAME_INITABSOLUTE(inaddr16172, inaddr172_offsets), + DNS_NAME_INITABSOLUTE(inaddr17172, inaddr172_offsets), + DNS_NAME_INITABSOLUTE(inaddr18172, inaddr172_offsets), + DNS_NAME_INITABSOLUTE(inaddr19172, inaddr172_offsets), + DNS_NAME_INITABSOLUTE(inaddr20172, inaddr172_offsets), + DNS_NAME_INITABSOLUTE(inaddr21172, inaddr172_offsets), + DNS_NAME_INITABSOLUTE(inaddr22172, inaddr172_offsets), + DNS_NAME_INITABSOLUTE(inaddr23172, inaddr172_offsets), + DNS_NAME_INITABSOLUTE(inaddr24172, inaddr172_offsets), + DNS_NAME_INITABSOLUTE(inaddr25172, inaddr172_offsets), + DNS_NAME_INITABSOLUTE(inaddr26172, inaddr172_offsets), + DNS_NAME_INITABSOLUTE(inaddr27172, inaddr172_offsets), + DNS_NAME_INITABSOLUTE(inaddr28172, inaddr172_offsets), + DNS_NAME_INITABSOLUTE(inaddr29172, inaddr172_offsets), + DNS_NAME_INITABSOLUTE(inaddr30172, inaddr172_offsets), + DNS_NAME_INITABSOLUTE(inaddr31172, inaddr172_offsets), + DNS_NAME_INITABSOLUTE(inaddr168192, inaddr192_offsets) +}; + +static unsigned char prisoner_data[] = "\010prisoner\004iana\003org"; +static unsigned char hostmaster_data[] = "\012hostmaster\014root-" + "servers\003org"; + +static unsigned char prisoner_offsets[] = { 0, 9, 14, 18 }; +static unsigned char hostmaster_offsets[] = { 0, 11, 24, 28 }; + +static dns_name_t const prisoner = DNS_NAME_INITABSOLUTE(prisoner_data, + prisoner_offsets); +static dns_name_t const hostmaster = DNS_NAME_INITABSOLUTE(hostmaster_data, + hostmaster_offsets); + +static void +warn_rfc1918(ns_client_t *client, dns_name_t *fname, dns_rdataset_t *rdataset) { + unsigned int i; + dns_rdata_t rdata = DNS_RDATA_INIT; + dns_rdata_soa_t soa; + dns_rdataset_t found; + isc_result_t result; + + for (i = 0; i < (sizeof(rfc1918names) / sizeof(*rfc1918names)); i++) { + if (dns_name_issubdomain(fname, &rfc1918names[i])) { + dns_rdataset_init(&found); + result = dns_ncache_getrdataset( + rdataset, &rfc1918names[i], dns_rdatatype_soa, + &found); + if (result != ISC_R_SUCCESS) { + return; + } + + result = dns_rdataset_first(&found); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + dns_rdataset_current(&found, &rdata); + result = dns_rdata_tostruct(&rdata, &soa, NULL); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + if (dns_name_equal(&soa.origin, &prisoner) && + dns_name_equal(&soa.contact, &hostmaster)) + { + char buf[DNS_NAME_FORMATSIZE]; + dns_name_format(fname, buf, sizeof(buf)); + ns_client_log(client, DNS_LOGCATEGORY_SECURITY, + NS_LOGMODULE_QUERY, + ISC_LOG_WARNING, + "RFC 1918 response from " + "Internet for %s", + buf); + } + dns_rdataset_disassociate(&found); + return; + } + } +} + +static void +query_findclosestnsec3(dns_name_t *qname, dns_db_t *db, + dns_dbversion_t *version, ns_client_t *client, + dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset, + dns_name_t *fname, bool exact, dns_name_t *found) { + unsigned char salt[256]; + size_t salt_length; + uint16_t iterations; + isc_result_t result; + unsigned int dboptions; + dns_fixedname_t fixed; + dns_hash_t hash; + dns_name_t name; + unsigned int skip = 0, labels; + dns_rdata_nsec3_t nsec3; + dns_rdata_t rdata = DNS_RDATA_INIT; + bool optout; + dns_clientinfomethods_t cm; + dns_clientinfo_t ci; + + salt_length = sizeof(salt); + result = dns_db_getnsec3parameters(db, version, &hash, NULL, + &iterations, salt, &salt_length); + if (result != ISC_R_SUCCESS) { + return; + } + + dns_name_init(&name, NULL); + dns_name_clone(qname, &name); + labels = dns_name_countlabels(&name); + dns_clientinfomethods_init(&cm, ns_client_sourceip); + dns_clientinfo_init(&ci, client, NULL); + + /* + * Map unknown algorithm to known value. + */ + if (hash == DNS_NSEC3_UNKNOWNALG) { + hash = 1; + } + +again: + dns_fixedname_init(&fixed); + result = dns_nsec3_hashname(&fixed, NULL, NULL, &name, + dns_db_origin(db), hash, iterations, salt, + salt_length); + if (result != ISC_R_SUCCESS) { + return; + } + + dboptions = client->query.dboptions | DNS_DBFIND_FORCENSEC3; + result = dns_db_findext(db, dns_fixedname_name(&fixed), version, + dns_rdatatype_nsec3, dboptions, client->now, + NULL, fname, &cm, &ci, rdataset, sigrdataset); + + if (result == DNS_R_NXDOMAIN) { + if (!dns_rdataset_isassociated(rdataset)) { + return; + } + result = dns_rdataset_first(rdataset); + INSIST(result == ISC_R_SUCCESS); + dns_rdataset_current(rdataset, &rdata); + result = dns_rdata_tostruct(&rdata, &nsec3, NULL); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + dns_rdata_reset(&rdata); + optout = ((nsec3.flags & DNS_NSEC3FLAG_OPTOUT) != 0); + if (found != NULL && optout && + dns_name_issubdomain(&name, dns_db_origin(db))) + { + dns_rdataset_disassociate(rdataset); + if (dns_rdataset_isassociated(sigrdataset)) { + dns_rdataset_disassociate(sigrdataset); + } + skip++; + dns_name_getlabelsequence(qname, skip, labels - skip, + &name); + ns_client_log(client, DNS_LOGCATEGORY_DNSSEC, + NS_LOGMODULE_QUERY, ISC_LOG_DEBUG(3), + "looking for closest provable encloser"); + goto again; + } + if (exact) { + ns_client_log(client, DNS_LOGCATEGORY_DNSSEC, + NS_LOGMODULE_QUERY, ISC_LOG_WARNING, + "expected a exact match NSEC3, got " + "a covering record"); + } + } else if (result != ISC_R_SUCCESS) { + return; + } else if (!exact) { + ns_client_log(client, DNS_LOGCATEGORY_DNSSEC, + NS_LOGMODULE_QUERY, ISC_LOG_WARNING, + "expected covering NSEC3, got an exact match"); + } + if (found == qname) { + if (skip != 0U) { + dns_name_getlabelsequence(qname, skip, labels - skip, + found); + } + } else if (found != NULL) { + dns_name_copy(&name, found); + } + return; +} + +static uint32_t +dns64_ttl(dns_db_t *db, dns_dbversion_t *version) { + dns_dbnode_t *node = NULL; + dns_rdata_soa_t soa; + dns_rdata_t rdata = DNS_RDATA_INIT; + dns_rdataset_t rdataset; + isc_result_t result; + uint32_t ttl = UINT32_MAX; + + dns_rdataset_init(&rdataset); + + result = dns_db_getoriginnode(db, &node); + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + + result = dns_db_findrdataset(db, node, version, dns_rdatatype_soa, 0, 0, + &rdataset, NULL); + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + result = dns_rdataset_first(&rdataset); + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + + dns_rdataset_current(&rdataset, &rdata); + result = dns_rdata_tostruct(&rdata, &soa, NULL); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + ttl = ISC_MIN(rdataset.ttl, soa.minimum); + +cleanup: + if (dns_rdataset_isassociated(&rdataset)) { + dns_rdataset_disassociate(&rdataset); + } + if (node != NULL) { + dns_db_detachnode(db, &node); + } + return (ttl); +} + +static bool +dns64_aaaaok(ns_client_t *client, dns_rdataset_t *rdataset, + dns_rdataset_t *sigrdataset) { + isc_netaddr_t netaddr; + dns_aclenv_t *env = client->manager->aclenv; + dns_dns64_t *dns64 = ISC_LIST_HEAD(client->view->dns64); + unsigned int flags = 0; + unsigned int i, count; + bool *aaaaok; + + INSIST(client->query.dns64_aaaaok == NULL); + INSIST(client->query.dns64_aaaaoklen == 0); + INSIST(client->query.dns64_aaaa == NULL); + INSIST(client->query.dns64_sigaaaa == NULL); + + if (dns64 == NULL) { + return (true); + } + + if (RECURSIONOK(client)) { + flags |= DNS_DNS64_RECURSIVE; + } + + if (WANTDNSSEC(client) && sigrdataset != NULL && + dns_rdataset_isassociated(sigrdataset)) + { + flags |= DNS_DNS64_DNSSEC; + } + + count = dns_rdataset_count(rdataset); + aaaaok = isc_mem_get(client->mctx, sizeof(bool) * count); + + isc_netaddr_fromsockaddr(&netaddr, &client->peeraddr); + if (dns_dns64_aaaaok(dns64, &netaddr, client->signer, env, flags, + rdataset, aaaaok, count)) + { + for (i = 0; i < count; i++) { + if (aaaaok != NULL && !aaaaok[i]) { + SAVE(client->query.dns64_aaaaok, aaaaok); + client->query.dns64_aaaaoklen = count; + break; + } + } + if (aaaaok != NULL) { + isc_mem_put(client->mctx, aaaaok, sizeof(bool) * count); + } + return (true); + } + if (aaaaok != NULL) { + isc_mem_put(client->mctx, aaaaok, sizeof(bool) * count); + } + return (false); +} + +/* + * Look for the name and type in the redirection zone. If found update + * the arguments as appropriate. Return true if a update was + * performed. + * + * Only perform the update if the client is in the allow query acl and + * returning the update would not cause a DNSSEC validation failure. + */ +static isc_result_t +redirect(ns_client_t *client, dns_name_t *name, dns_rdataset_t *rdataset, + dns_dbnode_t **nodep, dns_db_t **dbp, dns_dbversion_t **versionp, + dns_rdatatype_t qtype) { + dns_db_t *db = NULL; + dns_dbnode_t *node = NULL; + dns_fixedname_t fixed; + dns_name_t *found; + dns_rdataset_t trdataset; + isc_result_t result; + dns_rdatatype_t type; + dns_clientinfomethods_t cm; + dns_clientinfo_t ci; + ns_dbversion_t *dbversion; + + CTRACE(ISC_LOG_DEBUG(3), "redirect"); + + if (client->view->redirect == NULL) { + return (ISC_R_NOTFOUND); + } + + found = dns_fixedname_initname(&fixed); + dns_rdataset_init(&trdataset); + + dns_clientinfomethods_init(&cm, ns_client_sourceip); + dns_clientinfo_init(&ci, client, NULL); + dns_clientinfo_setecs(&ci, &client->ecs); + + if (WANTDNSSEC(client) && dns_db_iszone(*dbp) && dns_db_issecure(*dbp)) + { + return (ISC_R_NOTFOUND); + } + + if (WANTDNSSEC(client) && dns_rdataset_isassociated(rdataset)) { + if (rdataset->trust == dns_trust_secure) { + return (ISC_R_NOTFOUND); + } + if (rdataset->trust == dns_trust_ultimate && + (rdataset->type == dns_rdatatype_nsec || + rdataset->type == dns_rdatatype_nsec3)) + { + return (ISC_R_NOTFOUND); + } + if ((rdataset->attributes & DNS_RDATASETATTR_NEGATIVE) != 0) { + for (result = dns_rdataset_first(rdataset); + result == ISC_R_SUCCESS; + result = dns_rdataset_next(rdataset)) + { + dns_ncache_current(rdataset, found, &trdataset); + type = trdataset.type; + dns_rdataset_disassociate(&trdataset); + if (type == dns_rdatatype_nsec || + type == dns_rdatatype_nsec3 || + type == dns_rdatatype_rrsig) + { + return (ISC_R_NOTFOUND); + } + } + } + } + + result = ns_client_checkaclsilent( + client, NULL, dns_zone_getqueryacl(client->view->redirect), + true); + if (result != ISC_R_SUCCESS) { + return (ISC_R_NOTFOUND); + } + + result = dns_zone_getdb(client->view->redirect, &db); + if (result != ISC_R_SUCCESS) { + return (ISC_R_NOTFOUND); + } + + dbversion = ns_client_findversion(client, db); + if (dbversion == NULL) { + dns_db_detach(&db); + return (ISC_R_NOTFOUND); + } + + /* + * Lookup the requested data in the redirect zone. + */ + result = dns_db_findext(db, client->query.qname, dbversion->version, + qtype, DNS_DBFIND_NOZONECUT, client->now, &node, + found, &cm, &ci, &trdataset, NULL); + if (result == DNS_R_NXRRSET || result == DNS_R_NCACHENXRRSET) { + if (dns_rdataset_isassociated(rdataset)) { + dns_rdataset_disassociate(rdataset); + } + if (dns_rdataset_isassociated(&trdataset)) { + dns_rdataset_disassociate(&trdataset); + } + goto nxrrset; + } else if (result != ISC_R_SUCCESS) { + if (dns_rdataset_isassociated(&trdataset)) { + dns_rdataset_disassociate(&trdataset); + } + if (node != NULL) { + dns_db_detachnode(db, &node); + } + dns_db_detach(&db); + return (ISC_R_NOTFOUND); + } + + CTRACE(ISC_LOG_DEBUG(3), "redirect: found data: done"); + dns_name_copy(found, name); + if (dns_rdataset_isassociated(rdataset)) { + dns_rdataset_disassociate(rdataset); + } + if (dns_rdataset_isassociated(&trdataset)) { + dns_rdataset_clone(&trdataset, rdataset); + dns_rdataset_disassociate(&trdataset); + } +nxrrset: + if (*nodep != NULL) { + dns_db_detachnode(*dbp, nodep); + } + dns_db_detach(dbp); + dns_db_attachnode(db, node, nodep); + dns_db_attach(db, dbp); + dns_db_detachnode(db, &node); + dns_db_detach(&db); + *versionp = dbversion->version; + + client->query.attributes |= (NS_QUERYATTR_NOAUTHORITY | + NS_QUERYATTR_NOADDITIONAL); + + return (result); +} + +static isc_result_t +redirect2(ns_client_t *client, dns_name_t *name, dns_rdataset_t *rdataset, + dns_dbnode_t **nodep, dns_db_t **dbp, dns_dbversion_t **versionp, + dns_rdatatype_t qtype, bool *is_zonep) { + dns_db_t *db = NULL; + dns_dbnode_t *node = NULL; + dns_fixedname_t fixed; + dns_fixedname_t fixedredirect; + dns_name_t *found, *redirectname; + dns_rdataset_t trdataset; + isc_result_t result; + dns_rdatatype_t type; + dns_clientinfomethods_t cm; + dns_clientinfo_t ci; + dns_dbversion_t *version = NULL; + dns_zone_t *zone = NULL; + bool is_zone; + unsigned int labels; + unsigned int options; + + CTRACE(ISC_LOG_DEBUG(3), "redirect2"); + + if (client->view->redirectzone == NULL) { + return (ISC_R_NOTFOUND); + } + + if (dns_name_issubdomain(name, client->view->redirectzone)) { + return (ISC_R_NOTFOUND); + } + + found = dns_fixedname_initname(&fixed); + dns_rdataset_init(&trdataset); + + dns_clientinfomethods_init(&cm, ns_client_sourceip); + dns_clientinfo_init(&ci, client, NULL); + dns_clientinfo_setecs(&ci, &client->ecs); + + if (WANTDNSSEC(client) && dns_db_iszone(*dbp) && dns_db_issecure(*dbp)) + { + return (ISC_R_NOTFOUND); + } + + if (WANTDNSSEC(client) && dns_rdataset_isassociated(rdataset)) { + if (rdataset->trust == dns_trust_secure) { + return (ISC_R_NOTFOUND); + } + if (rdataset->trust == dns_trust_ultimate && + (rdataset->type == dns_rdatatype_nsec || + rdataset->type == dns_rdatatype_nsec3)) + { + return (ISC_R_NOTFOUND); + } + if ((rdataset->attributes & DNS_RDATASETATTR_NEGATIVE) != 0) { + for (result = dns_rdataset_first(rdataset); + result == ISC_R_SUCCESS; + result = dns_rdataset_next(rdataset)) + { + dns_ncache_current(rdataset, found, &trdataset); + type = trdataset.type; + dns_rdataset_disassociate(&trdataset); + if (type == dns_rdatatype_nsec || + type == dns_rdatatype_nsec3 || + type == dns_rdatatype_rrsig) + { + return (ISC_R_NOTFOUND); + } + } + } + } + + redirectname = dns_fixedname_initname(&fixedredirect); + labels = dns_name_countlabels(client->query.qname); + if (labels > 1U) { + dns_name_t prefix; + + dns_name_init(&prefix, NULL); + dns_name_getlabelsequence(client->query.qname, 0, labels - 1, + &prefix); + result = dns_name_concatenate(&prefix, + client->view->redirectzone, + redirectname, NULL); + if (result != ISC_R_SUCCESS) { + return (ISC_R_NOTFOUND); + } + } else { + dns_name_copy(redirectname, client->view->redirectzone); + } + + options = 0; + result = query_getdb(client, redirectname, qtype, options, &zone, &db, + &version, &is_zone); + if (result != ISC_R_SUCCESS) { + return (ISC_R_NOTFOUND); + } + if (zone != NULL) { + dns_zone_detach(&zone); + } + + /* + * Lookup the requested data in the redirect zone. + */ + result = dns_db_findext(db, redirectname, version, qtype, 0, + client->now, &node, found, &cm, &ci, &trdataset, + NULL); + if (result == DNS_R_NXRRSET || result == DNS_R_NCACHENXRRSET) { + if (dns_rdataset_isassociated(rdataset)) { + dns_rdataset_disassociate(rdataset); + } + if (dns_rdataset_isassociated(&trdataset)) { + dns_rdataset_disassociate(&trdataset); + } + goto nxrrset; + } else if (result == ISC_R_NOTFOUND || result == DNS_R_DELEGATION) { + /* + * Cleanup. + */ + if (dns_rdataset_isassociated(&trdataset)) { + dns_rdataset_disassociate(&trdataset); + } + if (node != NULL) { + dns_db_detachnode(db, &node); + } + dns_db_detach(&db); + /* + * Don't loop forever if the lookup failed last time. + */ + if (!REDIRECT(client)) { + result = ns_query_recurse(client, qtype, redirectname, + NULL, NULL, true); + if (result == ISC_R_SUCCESS) { + client->query.attributes |= + NS_QUERYATTR_RECURSING; + client->query.attributes |= + NS_QUERYATTR_REDIRECT; + return (DNS_R_CONTINUE); + } + } + return (ISC_R_NOTFOUND); + } else if (result != ISC_R_SUCCESS) { + if (dns_rdataset_isassociated(&trdataset)) { + dns_rdataset_disassociate(&trdataset); + } + if (node != NULL) { + dns_db_detachnode(db, &node); + } + dns_db_detach(&db); + return (ISC_R_NOTFOUND); + } + + CTRACE(ISC_LOG_DEBUG(3), "redirect2: found data: done"); + /* + * Adjust the found name to not include the redirectzone suffix. + */ + dns_name_split(found, dns_name_countlabels(client->view->redirectzone), + found, NULL); + /* + * Make the name absolute. + */ + result = dns_name_concatenate(found, dns_rootname, found, NULL); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + + dns_name_copy(found, name); + if (dns_rdataset_isassociated(rdataset)) { + dns_rdataset_disassociate(rdataset); + } + if (dns_rdataset_isassociated(&trdataset)) { + dns_rdataset_clone(&trdataset, rdataset); + dns_rdataset_disassociate(&trdataset); + } +nxrrset: + if (*nodep != NULL) { + dns_db_detachnode(*dbp, nodep); + } + dns_db_detach(dbp); + dns_db_attachnode(db, node, nodep); + dns_db_attach(db, dbp); + dns_db_detachnode(db, &node); + dns_db_detach(&db); + *is_zonep = is_zone; + *versionp = version; + + client->query.attributes |= (NS_QUERYATTR_NOAUTHORITY | + NS_QUERYATTR_NOADDITIONAL); + + return (result); +} + +/*% + * Initialize query context 'qctx'. Run by query_setup() when + * first handling a client query, and by query_resume() when + * returning from recursion. + * + * Whenever this function is called, qctx_destroy() must be called + * when leaving the scope or freeing the qctx. + */ +static void +qctx_init(ns_client_t *client, dns_fetchevent_t **eventp, dns_rdatatype_t qtype, + query_ctx_t *qctx) { + REQUIRE(qctx != NULL); + REQUIRE(client != NULL); + + memset(qctx, 0, sizeof(*qctx)); + + /* Set this first so CCTRACE will work */ + qctx->client = client; + + dns_view_attach(client->view, &qctx->view); + + CCTRACE(ISC_LOG_DEBUG(3), "qctx_init"); + + if (eventp != NULL) { + qctx->event = *eventp; + *eventp = NULL; + } else { + qctx->event = NULL; + } + qctx->qtype = qctx->type = qtype; + qctx->result = ISC_R_SUCCESS; + qctx->findcoveringnsec = qctx->view->synthfromdnssec; + + /* + * If it's an RRSIG or SIG query, we'll iterate the node. + */ + if (qctx->qtype == dns_rdatatype_rrsig || + qctx->qtype == dns_rdatatype_sig) + { + qctx->type = dns_rdatatype_any; + } + + CALL_HOOK_NORETURN(NS_QUERY_QCTX_INITIALIZED, qctx); +} + +/* + * Make 'dst' and exact copy of 'src', with exception of the + * option field, which is reset to zero. + * This function also attaches dst's view and db to the src's + * view and cachedb. + */ +static void +qctx_copy(const query_ctx_t *qctx, query_ctx_t *dst) { + REQUIRE(qctx != NULL); + REQUIRE(dst != NULL); + + memmove(dst, qctx, sizeof(*dst)); + dst->view = NULL; + dst->db = NULL; + dst->options = 0; + dns_view_attach(qctx->view, &dst->view); + dns_db_attach(qctx->view->cachedb, &dst->db); + CCTRACE(ISC_LOG_DEBUG(3), "qctx_copy"); +} + +/*% + * Clean up and disassociate the rdataset and node pointers in qctx. + */ +static void +qctx_clean(query_ctx_t *qctx) { + if (qctx->rdataset != NULL && dns_rdataset_isassociated(qctx->rdataset)) + { + dns_rdataset_disassociate(qctx->rdataset); + } + if (qctx->sigrdataset != NULL && + dns_rdataset_isassociated(qctx->sigrdataset)) + { + dns_rdataset_disassociate(qctx->sigrdataset); + } + if (qctx->db != NULL && qctx->node != NULL) { + dns_db_detachnode(qctx->db, &qctx->node); + } +} + +/*% + * Free any allocated memory associated with qctx. + */ +static void +qctx_freedata(query_ctx_t *qctx) { + if (qctx->rdataset != NULL) { + ns_client_putrdataset(qctx->client, &qctx->rdataset); + } + + if (qctx->sigrdataset != NULL) { + ns_client_putrdataset(qctx->client, &qctx->sigrdataset); + } + + if (qctx->fname != NULL) { + ns_client_releasename(qctx->client, &qctx->fname); + } + + if (qctx->db != NULL) { + INSIST(qctx->node == NULL); + dns_db_detach(&qctx->db); + } + + if (qctx->zone != NULL) { + dns_zone_detach(&qctx->zone); + } + + if (qctx->zdb != NULL) { + ns_client_putrdataset(qctx->client, &qctx->zsigrdataset); + ns_client_putrdataset(qctx->client, &qctx->zrdataset); + ns_client_releasename(qctx->client, &qctx->zfname); + dns_db_detachnode(qctx->zdb, &qctx->znode); + dns_db_detach(&qctx->zdb); + } + + if (qctx->event != NULL && !qctx->client->nodetach) { + free_devent(qctx->client, ISC_EVENT_PTR(&qctx->event), + &qctx->event); + } +} + +static void +qctx_destroy(query_ctx_t *qctx) { + CALL_HOOK_NORETURN(NS_QUERY_QCTX_DESTROYED, qctx); + + dns_view_detach(&qctx->view); +} + +/* + * Call SAVE but set 'a' to NULL first so as not to assert. + */ +#define INITANDSAVE(a, b) \ + do { \ + a = NULL; \ + SAVE(a, b); \ + } while (0) + +/* + * "save" qctx data from 'src' to 'tgt'. + * It essentially moves ownership of the data from src to tgt, so the former + * becomes unusable except for final cleanup (such as by qctx_destroy). + * Note: this function doesn't attach to the client's handle. It's the caller's + * responsibility to do it if it's necessary. + */ +static void +qctx_save(query_ctx_t *src, query_ctx_t *tgt) { + /* First copy all fields in a straightforward way */ + *tgt = *src; + + /* Then "move" pointers (except client and view) */ + INITANDSAVE(tgt->dbuf, src->dbuf); + INITANDSAVE(tgt->fname, src->fname); + INITANDSAVE(tgt->tname, src->tname); + INITANDSAVE(tgt->rdataset, src->rdataset); + INITANDSAVE(tgt->sigrdataset, src->sigrdataset); + INITANDSAVE(tgt->noqname, src->noqname); + INITANDSAVE(tgt->event, src->event); + INITANDSAVE(tgt->db, src->db); + INITANDSAVE(tgt->version, src->version); + INITANDSAVE(tgt->node, src->node); + INITANDSAVE(tgt->zdb, src->zdb); + INITANDSAVE(tgt->znode, src->znode); + INITANDSAVE(tgt->zfname, src->zfname); + INITANDSAVE(tgt->zversion, src->zversion); + INITANDSAVE(tgt->zrdataset, src->zrdataset); + INITANDSAVE(tgt->zsigrdataset, src->zsigrdataset); + INITANDSAVE(tgt->rpz_st, src->rpz_st); + INITANDSAVE(tgt->zone, src->zone); + + /* View has to stay in 'src' for qctx_destroy. */ + tgt->view = NULL; + dns_view_attach(src->view, &tgt->view); +} + +/*% + * Log detailed information about the query immediately after + * the client request or a return from recursion. + */ +static void +query_trace(query_ctx_t *qctx) { +#ifdef WANT_QUERYTRACE + char mbuf[2 * DNS_NAME_FORMATSIZE]; + char qbuf[DNS_NAME_FORMATSIZE]; + + if (qctx->client->query.origqname != NULL) { + dns_name_format(qctx->client->query.origqname, qbuf, + sizeof(qbuf)); + } else { + snprintf(qbuf, sizeof(qbuf), "<unset>"); + } + + snprintf(mbuf, sizeof(mbuf) - 1, + "client attr:0x%x, query attr:0x%X, restarts:%u, " + "origqname:%s, timer:%d, authdb:%d, referral:%d", + qctx->client->attributes, qctx->client->query.attributes, + qctx->client->query.restarts, qbuf, + (int)qctx->client->query.timerset, + (int)qctx->client->query.authdbset, + (int)qctx->client->query.isreferral); + CCTRACE(ISC_LOG_DEBUG(3), mbuf); +#else /* ifdef WANT_QUERYTRACE */ + UNUSED(qctx); +#endif /* ifdef WANT_QUERYTRACE */ +} + +/* + * Set up query processing for the current query of 'client'. + * Calls qctx_init() to initialize a query context, checks + * the SERVFAIL cache, then hands off processing to ns__query_start(). + * + * This is called only from ns_query_start(), to begin a query + * for the first time. Restarting an existing query (for + * instance, to handle CNAME lookups), is done by calling + * ns__query_start() again with the same query context. Resuming from + * recursion is handled by query_resume(). + */ +static isc_result_t +query_setup(ns_client_t *client, dns_rdatatype_t qtype) { + isc_result_t result = ISC_R_UNSET; + query_ctx_t qctx; + + qctx_init(client, NULL, qtype, &qctx); + query_trace(&qctx); + + CALL_HOOK(NS_QUERY_SETUP, &qctx); + + /* + * Check SERVFAIL cache + */ + result = ns__query_sfcache(&qctx); + if (result != ISC_R_COMPLETE) { + qctx_destroy(&qctx); + return (result); + } + + result = ns__query_start(&qctx); + +cleanup: + qctx_destroy(&qctx); + return (result); +} + +static bool +get_root_key_sentinel_id(query_ctx_t *qctx, const char *ndata) { + unsigned int v = 0; + int i; + + for (i = 0; i < 5; i++) { + if (!isdigit((unsigned char)ndata[i])) { + return (false); + } + v *= 10; + v += ndata[i] - '0'; + } + if (v > 65535U) { + return (false); + } + qctx->client->query.root_key_sentinel_keyid = v; + return (true); +} + +/*% + * Find out if the query is for a root key sentinel and if so, record the type + * of root key sentinel query and the key id that is being checked for. + * + * The code is assuming a zero padded decimal field of width 5. + */ +static void +root_key_sentinel_detect(query_ctx_t *qctx) { + const char *ndata = (const char *)qctx->client->query.qname->ndata; + + if (qctx->client->query.qname->length > 30 && ndata[0] == 29 && + strncasecmp(ndata + 1, "root-key-sentinel-is-ta-", 24) == 0) + { + if (!get_root_key_sentinel_id(qctx, ndata + 25)) { + return; + } + qctx->client->query.root_key_sentinel_is_ta = true; + /* + * Simplify processing by disabling aggressive + * negative caching. + */ + qctx->findcoveringnsec = false; + ns_client_log(qctx->client, NS_LOGCATEGORY_TAT, + NS_LOGMODULE_QUERY, ISC_LOG_INFO, + "root-key-sentinel-is-ta query label found"); + } else if (qctx->client->query.qname->length > 31 && ndata[0] == 30 && + strncasecmp(ndata + 1, "root-key-sentinel-not-ta-", 25) == 0) + { + if (!get_root_key_sentinel_id(qctx, ndata + 26)) { + return; + } + qctx->client->query.root_key_sentinel_not_ta = true; + /* + * Simplify processing by disabling aggressive + * negative caching. + */ + qctx->findcoveringnsec = false; + ns_client_log(qctx->client, NS_LOGCATEGORY_TAT, + NS_LOGMODULE_QUERY, ISC_LOG_INFO, + "root-key-sentinel-not-ta query label found"); + } +} + +/*% + * Starting point for a client query or a chaining query. + * + * Called first by query_setup(), and then again as often as needed to + * follow a CNAME chain. Determines which authoritative database to + * search, then hands off processing to query_lookup(). + */ +isc_result_t +ns__query_start(query_ctx_t *qctx) { + isc_result_t result = ISC_R_UNSET; + CCTRACE(ISC_LOG_DEBUG(3), "ns__query_start"); + qctx->want_restart = false; + qctx->authoritative = false; + qctx->version = NULL; + qctx->zversion = NULL; + qctx->need_wildcardproof = false; + qctx->rpz = false; + + CALL_HOOK(NS_QUERY_START_BEGIN, qctx); + + /* + * If we require a server cookie then send back BADCOOKIE + * before we have done too much work. + */ + if (!TCP(qctx->client) && qctx->view->requireservercookie && + WANTCOOKIE(qctx->client) && !HAVECOOKIE(qctx->client)) + { + qctx->client->message->flags &= ~DNS_MESSAGEFLAG_AA; + qctx->client->message->flags &= ~DNS_MESSAGEFLAG_AD; + qctx->client->message->rcode = dns_rcode_badcookie; + return (ns_query_done(qctx)); + } + + if (qctx->view->checknames && + !dns_rdata_checkowner(qctx->client->query.qname, + qctx->client->message->rdclass, qctx->qtype, + false)) + { + char namebuf[DNS_NAME_FORMATSIZE]; + char typebuf[DNS_RDATATYPE_FORMATSIZE]; + char classbuf[DNS_RDATACLASS_FORMATSIZE]; + + dns_name_format(qctx->client->query.qname, namebuf, + sizeof(namebuf)); + dns_rdatatype_format(qctx->qtype, typebuf, sizeof(typebuf)); + dns_rdataclass_format(qctx->client->message->rdclass, classbuf, + sizeof(classbuf)); + ns_client_log(qctx->client, DNS_LOGCATEGORY_SECURITY, + NS_LOGMODULE_QUERY, ISC_LOG_ERROR, + "check-names failure %s/%s/%s", namebuf, typebuf, + classbuf); + QUERY_ERROR(qctx, DNS_R_REFUSED); + return (ns_query_done(qctx)); + } + + /* + * Setup for root key sentinel processing. + */ + if (qctx->view->root_key_sentinel && + qctx->client->query.restarts == 0 && + (qctx->qtype == dns_rdatatype_a || + qctx->qtype == dns_rdatatype_aaaa) && + (qctx->client->message->flags & DNS_MESSAGEFLAG_CD) == 0) + { + root_key_sentinel_detect(qctx); + } + + /* + * First we must find the right database. + */ + qctx->options &= DNS_GETDB_NOLOG; /* Preserve DNS_GETDB_NOLOG. */ + if (dns_rdatatype_atparent(qctx->qtype) && + !dns_name_equal(qctx->client->query.qname, dns_rootname)) + { + /* + * If authoritative data for this QTYPE is supposed to live in + * the parent zone, do not look for an exact match for QNAME, + * but rather for its containing zone (unless the QNAME is + * root). + */ + qctx->options |= DNS_GETDB_NOEXACT; + } + + result = query_getdb(qctx->client, qctx->client->query.qname, + qctx->qtype, qctx->options, &qctx->zone, &qctx->db, + &qctx->version, &qctx->is_zone); + if ((result != ISC_R_SUCCESS || !qctx->is_zone) && + qctx->qtype == dns_rdatatype_ds && !RECURSIONOK(qctx->client) && + (qctx->options & DNS_GETDB_NOEXACT) != 0) + { + /* + * This is a non-recursive QTYPE=DS query with QNAME whose + * parent we are not authoritative for. Check whether we are + * authoritative for QNAME, because if so, we need to send a + * "no data" response as required by RFC 4035, section 3.1.4.1. + */ + dns_db_t *tdb = NULL; + dns_zone_t *tzone = NULL; + dns_dbversion_t *tversion = NULL; + isc_result_t tresult; + + tresult = query_getzonedb( + qctx->client, qctx->client->query.qname, qctx->qtype, + DNS_GETDB_PARTIAL, &tzone, &tdb, &tversion); + if (tresult == ISC_R_SUCCESS) { + /* + * We are authoritative for QNAME. Attach the relevant + * zone to query context, set result to ISC_R_SUCCESS. + */ + qctx->options &= ~DNS_GETDB_NOEXACT; + ns_client_putrdataset(qctx->client, &qctx->rdataset); + if (qctx->db != NULL) { + dns_db_detach(&qctx->db); + } + if (qctx->zone != NULL) { + dns_zone_detach(&qctx->zone); + } + qctx->version = NULL; + RESTORE(qctx->version, tversion); + RESTORE(qctx->db, tdb); + RESTORE(qctx->zone, tzone); + qctx->is_zone = true; + result = ISC_R_SUCCESS; + } else { + /* + * We are not authoritative for QNAME. Clean up and + * leave result as it was. + */ + if (tdb != NULL) { + dns_db_detach(&tdb); + } + if (tzone != NULL) { + dns_zone_detach(&tzone); + } + } + } + /* + * If we did not find a database from which we can answer the query, + * respond with either REFUSED or SERVFAIL, depending on what the + * result of query_getdb() was. + */ + if (result != ISC_R_SUCCESS) { + if (result == DNS_R_REFUSED) { + if (WANTRECURSION(qctx->client)) { + inc_stats(qctx->client, + ns_statscounter_recurserej); + } else { + inc_stats(qctx->client, + ns_statscounter_authrej); + } + if (!PARTIALANSWER(qctx->client)) { + QUERY_ERROR(qctx, DNS_R_REFUSED); + } + } else { + CCTRACE(ISC_LOG_ERROR, "ns__query_start: query_getdb " + "failed"); + QUERY_ERROR(qctx, result); + } + return (ns_query_done(qctx)); + } + + /* + * We found a database from which we can answer the query. Update + * relevant query context flags if the answer is to be prepared using + * authoritative data. + */ + qctx->is_staticstub_zone = false; + if (qctx->is_zone) { + qctx->authoritative = true; + if (qctx->zone != NULL) { + if (dns_zone_gettype(qctx->zone) == dns_zone_mirror) { + qctx->authoritative = false; + } + if (dns_zone_gettype(qctx->zone) == dns_zone_staticstub) + { + qctx->is_staticstub_zone = true; + } + } + } + + /* + * Attach to the database which will be used to prepare the answer. + * Update query statistics. + */ + if (qctx->event == NULL && qctx->client->query.restarts == 0) { + if (qctx->is_zone) { + if (qctx->zone != NULL) { + /* + * if is_zone = true, zone = NULL then this is + * a DLZ zone. Don't attempt to attach zone. + */ + dns_zone_attach(qctx->zone, + &qctx->client->query.authzone); + } + dns_db_attach(qctx->db, &qctx->client->query.authdb); + } + qctx->client->query.authdbset = true; + + /* Track TCP vs UDP stats per zone */ + if (TCP(qctx->client)) { + inc_stats(qctx->client, ns_statscounter_tcp); + } else { + inc_stats(qctx->client, ns_statscounter_udp); + } + } + + if (!qctx->is_zone && (qctx->view->staleanswerclienttimeout == 0) && + dns_view_staleanswerenabled(qctx->view)) + { + /* + * If stale answers are enabled and + * stale-answer-client-timeout is zero, then we can promptly + * answer with a stale RRset if one is available in cache. + */ + qctx->options |= DNS_GETDB_STALEFIRST; + } + + result = query_lookup(qctx); + + /* + * Clear "look-also-for-stale-data" flag. + * If a fetch is created to resolve this query, then, + * when it completes, this option is not expected to be set. + */ + qctx->options &= ~DNS_GETDB_STALEFIRST; + +cleanup: + return (result); +} + +/* + * Allocate buffers in 'qctx' used to store query results. + * + * 'buffer' must be a pointer to an object whose lifetime + * doesn't expire while 'qctx' is in use. + */ +static isc_result_t +qctx_prepare_buffers(query_ctx_t *qctx, isc_buffer_t *buffer) { + REQUIRE(qctx != NULL); + REQUIRE(qctx->client != NULL); + REQUIRE(buffer != NULL); + + qctx->dbuf = ns_client_getnamebuf(qctx->client); + if (qctx->dbuf == NULL) { + CCTRACE(ISC_LOG_ERROR, + "qctx_prepare_buffers: ns_client_getnamebuf " + "failed"); + return (ISC_R_NOMEMORY); + } + + qctx->fname = ns_client_newname(qctx->client, qctx->dbuf, buffer); + if (qctx->fname == NULL) { + CCTRACE(ISC_LOG_ERROR, + "qctx_prepare_buffers: ns_client_newname failed"); + + return (ISC_R_NOMEMORY); + } + + qctx->rdataset = ns_client_newrdataset(qctx->client); + if (qctx->rdataset == NULL) { + CCTRACE(ISC_LOG_ERROR, + "qctx_prepare_buffers: ns_client_newrdataset failed"); + goto error; + } + + if ((WANTDNSSEC(qctx->client) || qctx->findcoveringnsec) && + (!qctx->is_zone || dns_db_issecure(qctx->db))) + { + qctx->sigrdataset = ns_client_newrdataset(qctx->client); + if (qctx->sigrdataset == NULL) { + CCTRACE(ISC_LOG_ERROR, + "qctx_prepare_buffers: " + "ns_client_newrdataset failed (2)"); + goto error; + } + } + + return (ISC_R_SUCCESS); + +error: + if (qctx->fname != NULL) { + ns_client_releasename(qctx->client, &qctx->fname); + } + if (qctx->rdataset != NULL) { + ns_client_putrdataset(qctx->client, &qctx->rdataset); + } + + return (ISC_R_NOMEMORY); +} + +/* + * Setup a new query context for resolving a query. + * + * This function is only called if both these conditions are met: + * 1. BIND is configured with stale-answer-client-timeout 0. + * 2. A stale RRset is found in cache during initial query + * database lookup. + * + * We continue with this function for refreshing/resolving an RRset + * after answering a client with stale data. + */ +static void +query_refresh_rrset(query_ctx_t *orig_qctx) { + isc_buffer_t buffer; + query_ctx_t qctx; + + REQUIRE(orig_qctx != NULL); + REQUIRE(orig_qctx->client != NULL); + + qctx_copy(orig_qctx, &qctx); + qctx.client->query.dboptions &= ~(DNS_DBFIND_STALETIMEOUT | + DNS_DBFIND_STALEOK | + DNS_DBFIND_STALEENABLED); + qctx.client->nodetach = false; + + /* + * We'll need some resources... + */ + if (qctx_prepare_buffers(&qctx, &buffer) != ISC_R_SUCCESS) { + dns_db_detach(&qctx.db); + qctx_destroy(&qctx); + return; + } + + /* + * Pretend we didn't find anything in cache. + */ + (void)query_gotanswer(&qctx, ISC_R_NOTFOUND); + + if (qctx.fname != NULL) { + ns_client_releasename(qctx.client, &qctx.fname); + } + if (qctx.rdataset != NULL) { + ns_client_putrdataset(qctx.client, &qctx.rdataset); + } + + qctx_destroy(&qctx); +} + +/*% + * Depending on the db lookup result, we can respond to the + * client this stale answer. + */ +static bool +stale_client_answer(isc_result_t result) { + switch (result) { + case ISC_R_SUCCESS: + case DNS_R_EMPTYNAME: + case DNS_R_NXRRSET: + case DNS_R_NCACHENXRRSET: + case DNS_R_CNAME: + case DNS_R_DNAME: + return (true); + default: + return (false); + } + + UNREACHABLE(); +} + +/*% + * Perform a local database lookup, in either an authoritative or + * cache database. If unable to answer, call ns_query_done(); otherwise + * hand off processing to query_gotanswer(). + */ +static isc_result_t +query_lookup(query_ctx_t *qctx) { + isc_buffer_t buffer; + isc_result_t result = ISC_R_UNSET; + dns_clientinfomethods_t cm; + dns_clientinfo_t ci; + dns_name_t *rpzqname = NULL; + char namebuf[DNS_NAME_FORMATSIZE]; + unsigned int dboptions; + dns_ttl_t stale_refresh = 0; + bool dbfind_stale = false; + bool stale_timeout = false; + bool answer_found = false; + bool stale_found = false; + bool stale_refresh_window = false; + uint16_t ede = 0; + + CCTRACE(ISC_LOG_DEBUG(3), "query_lookup"); + + CALL_HOOK(NS_QUERY_LOOKUP_BEGIN, qctx); + + dns_clientinfomethods_init(&cm, ns_client_sourceip); + dns_clientinfo_init(&ci, qctx->client, NULL); + if (HAVEECS(qctx->client)) { + dns_clientinfo_setecs(&ci, &qctx->client->ecs); + } + + /* + * We'll need some resources... + */ + result = qctx_prepare_buffers(qctx, &buffer); + if (result != ISC_R_SUCCESS) { + QUERY_ERROR(qctx, result); + return (ns_query_done(qctx)); + } + + /* + * Now look for an answer in the database. + */ + if (qctx->dns64 && qctx->rpz) { + rpzqname = qctx->client->query.rpz_st->p_name; + } else { + rpzqname = qctx->client->query.qname; + } + + if ((qctx->options & DNS_GETDB_STALEFIRST) != 0) { + /* + * If DNS_GETDB_STALEFIRST is set, it means that a stale + * RRset may be returned as part of this lookup. An attempt + * to refresh the RRset will still take place if an + * active RRset is not available. + */ + qctx->client->query.dboptions |= DNS_DBFIND_STALETIMEOUT; + } + + dboptions = qctx->client->query.dboptions; + if (!qctx->is_zone && qctx->findcoveringnsec && + (qctx->type != dns_rdatatype_null || !dns_name_istat(rpzqname))) + { + dboptions |= DNS_DBFIND_COVERINGNSEC; + } + + (void)dns_db_getservestalerefresh(qctx->client->view->cachedb, + &stale_refresh); + if (stale_refresh > 0 && + dns_view_staleanswerenabled(qctx->client->view)) + { + dboptions |= DNS_DBFIND_STALEENABLED; + } + + result = dns_db_findext(qctx->db, rpzqname, qctx->version, qctx->type, + dboptions, qctx->client->now, &qctx->node, + qctx->fname, &cm, &ci, qctx->rdataset, + qctx->sigrdataset); + + /* + * Fixup fname and sigrdataset. + */ + if (qctx->dns64 && qctx->rpz) { + dns_name_copy(qctx->client->query.qname, qctx->fname); + if (qctx->sigrdataset != NULL && + dns_rdataset_isassociated(qctx->sigrdataset)) + { + dns_rdataset_disassociate(qctx->sigrdataset); + } + } + + if (!qctx->is_zone) { + dns_cache_updatestats(qctx->view->cache, result); + } + + /* + * If DNS_DBFIND_STALEOK is set this means we are dealing with a + * lookup following a failed lookup and it is okay to serve a stale + * answer. This will (re)start the 'stale-refresh-time' window in + * rbtdb, tracking the last time the RRset lookup failed. + */ + dbfind_stale = ((dboptions & DNS_DBFIND_STALEOK) != 0); + + /* + * If DNS_DBFIND_STALEENABLED is set, this may be a normal lookup, but + * we are allowed to immediately respond with a stale answer if the + * request is within the 'stale-refresh-time' window. + */ + stale_refresh_window = (STALE_WINDOW(qctx->rdataset) && + (dboptions & DNS_DBFIND_STALEENABLED) != 0); + + /* + * If DNS_DBFIND_STALETIMEOUT is set, a stale answer is requested. + * This can happen if 'stale-answer-client-timeout' is enabled. + * + * If 'stale-answer-client-timeout' is set to 0, and a stale + * answer is found, send it to the client, and try to refresh the + * RRset. + * + * If 'stale-answer-client-timeout' is non-zero, and a stale + * answer is found, send it to the client. Don't try to refresh the + * RRset because a fetch is already in progress. + */ + stale_timeout = ((dboptions & DNS_DBFIND_STALETIMEOUT) != 0); + + if (dns_rdataset_isassociated(qctx->rdataset) && + dns_rdataset_count(qctx->rdataset) > 0 && !STALE(qctx->rdataset)) + { + /* Found non-stale usable rdataset. */ + answer_found = true; + } + + if (dbfind_stale || stale_refresh_window || stale_timeout) { + dns_name_format(qctx->client->query.qname, namebuf, + sizeof(namebuf)); + + inc_stats(qctx->client, ns_statscounter_trystale); + + if (dns_rdataset_isassociated(qctx->rdataset) && + dns_rdataset_count(qctx->rdataset) > 0 && + STALE(qctx->rdataset)) + { + stale_found = true; + if (result == DNS_R_NCACHENXDOMAIN || + result == DNS_R_NXDOMAIN) + { + ede = DNS_EDE_STALENXANSWER; + } else { + ede = DNS_EDE_STALEANSWER; + } + qctx->rdataset->ttl = qctx->view->staleanswerttl; + inc_stats(qctx->client, ns_statscounter_usedstale); + } else { + stale_found = false; + } + } + + if (dbfind_stale) { + isc_log_write(ns_lctx, NS_LOGCATEGORY_SERVE_STALE, + NS_LOGMODULE_QUERY, ISC_LOG_INFO, + "%s resolver failure, stale answer %s", namebuf, + stale_found ? "used" : "unavailable"); + if (stale_found) { + ns_client_extendederror(qctx->client, ede, + "resolver failure"); + } else if (!answer_found) { + /* + * Resolver failure, no stale data, nothing more we + * can do, return SERVFAIL. + */ + QUERY_ERROR(qctx, DNS_R_SERVFAIL); + return (ns_query_done(qctx)); + } + } else if (stale_refresh_window) { + /* + * A recent lookup failed, so during this time window we are + * allowed to return stale data immediately. + */ + isc_log_write(ns_lctx, NS_LOGCATEGORY_SERVE_STALE, + NS_LOGMODULE_QUERY, ISC_LOG_INFO, + "%s query within stale refresh time, stale " + "answer %s", + namebuf, stale_found ? "used" : "unavailable"); + + if (stale_found) { + ns_client_extendederror( + qctx->client, ede, + "query within stale refresh time window"); + } else if (!answer_found) { + /* + * During the stale refresh window explicitly do not try + * to refresh the data, because a recent lookup failed. + */ + QUERY_ERROR(qctx, DNS_R_SERVFAIL); + return (ns_query_done(qctx)); + } + } else if (stale_timeout) { + if ((qctx->options & DNS_GETDB_STALEFIRST) != 0) { + if (!stale_found && !answer_found) { + /* + * We have nothing useful in cache to return + * immediately. + */ + qctx_clean(qctx); + qctx_freedata(qctx); + dns_db_attach(qctx->client->view->cachedb, + &qctx->db); + qctx->client->query.dboptions &= + ~DNS_DBFIND_STALETIMEOUT; + qctx->options &= ~DNS_GETDB_STALEFIRST; + if (qctx->client->query.fetch != NULL) { + dns_resolver_destroyfetch( + &qctx->client->query.fetch); + } + return (query_lookup(qctx)); + } else if (stale_client_answer(result)) { + /* + * Immediately return the stale answer, start a + * resolver fetch to refresh the data in cache. + */ + isc_log_write( + ns_lctx, NS_LOGCATEGORY_SERVE_STALE, + NS_LOGMODULE_QUERY, ISC_LOG_INFO, + "%s stale answer used, an attempt to " + "refresh the RRset will still be made", + namebuf); + + qctx->refresh_rrset = STALE(qctx->rdataset); + /* + * If we are refreshing the RRSet, we must not + * detach from the client in query_send(). + */ + qctx->client->nodetach = qctx->refresh_rrset; + + if (stale_found) { + ns_client_extendederror( + qctx->client, ede, + "stale data prioritized over " + "lookup"); + } + } + } else { + /* + * The 'stale-answer-client-timeout' triggered, return + * the stale answer if available, otherwise wait until + * the resolver finishes. + */ + isc_log_write(ns_lctx, NS_LOGCATEGORY_SERVE_STALE, + NS_LOGMODULE_QUERY, ISC_LOG_INFO, + "%s client timeout, stale answer %s", + namebuf, + stale_found ? "used" : "unavailable"); + if (stale_found) { + ns_client_extendederror(qctx->client, ede, + "client timeout"); + } else if (!answer_found) { + return (result); + } + + if (!stale_client_answer(result)) { + return (result); + } + + /* + * There still might be real answer later. Mark the + * query so we'll know we can skip answering. + */ + qctx->client->query.attributes |= + NS_QUERYATTR_STALEPENDING; + } + } + + if (stale_timeout && (answer_found || stale_found)) { + /* + * Mark RRsets that we are adding to the client message on a + * lookup during 'stale-answer-client-timeout', so we can + * clean it up if needed when we resume from recursion. + */ + qctx->client->query.attributes |= NS_QUERYATTR_STALEOK; + qctx->rdataset->attributes |= DNS_RDATASETATTR_STALE_ADDED; + } + + result = query_gotanswer(qctx, result); + +cleanup: + return (result); +} + +/* + * Clear all rdatasets from the message that are in the given section and + * that have the 'attr' attribute set. + */ +static void +message_clearrdataset(dns_message_t *msg, unsigned int attr) { + unsigned int i; + dns_name_t *name, *next_name; + dns_rdataset_t *rds, *next_rds; + + /* + * Clean up name lists by calling the rdataset disassociate function. + */ + for (i = DNS_SECTION_ANSWER; i < DNS_SECTION_MAX; i++) { + name = ISC_LIST_HEAD(msg->sections[i]); + while (name != NULL) { + next_name = ISC_LIST_NEXT(name, link); + + rds = ISC_LIST_HEAD(name->list); + while (rds != NULL) { + next_rds = ISC_LIST_NEXT(rds, link); + if ((rds->attributes & attr) != attr) { + rds = next_rds; + continue; + } + ISC_LIST_UNLINK(name->list, rds, link); + INSIST(dns_rdataset_isassociated(rds)); + dns_rdataset_disassociate(rds); + isc_mempool_put(msg->rdspool, rds); + rds = next_rds; + } + + if (ISC_LIST_EMPTY(name->list)) { + ISC_LIST_UNLINK(msg->sections[i], name, link); + if (dns_name_dynamic(name)) { + dns_name_free(name, msg->mctx); + } + isc_mempool_put(msg->namepool, name); + } + + name = next_name; + } + } +} + +/* + * Clear any rdatasets from the client's message that were added on a lookup + * due to a client timeout. + */ +static void +query_clear_stale(ns_client_t *client) { + message_clearrdataset(client->message, DNS_RDATASETATTR_STALE_ADDED); +} + +/* + * Create a new query context with the sole intent of looking up for a stale + * RRset in cache. If an entry is found, we mark the original query as + * answered, in order to avoid answering the query twice, when the original + * fetch finishes. + */ +static void +query_lookup_stale(ns_client_t *client) { + query_ctx_t qctx; + + qctx_init(client, NULL, client->query.qtype, &qctx); + dns_db_attach(client->view->cachedb, &qctx.db); + client->query.attributes &= ~NS_QUERYATTR_RECURSIONOK; + client->query.dboptions |= DNS_DBFIND_STALETIMEOUT; + client->nodetach = true; + (void)query_lookup(&qctx); + if (qctx.node != NULL) { + dns_db_detachnode(qctx.db, &qctx.node); + } + qctx_freedata(&qctx); + qctx_destroy(&qctx); +} + +/* + * Event handler to resume processing a query after recursion, or when a + * client timeout is triggered. If the query has timed out or been cancelled + * or the system is shutting down, clean up and exit. If a client timeout is + * triggered, see if we can respond with a stale answer from cache. Otherwise, + * call query_resume() to continue the ongoing work. + */ +static void +fetch_callback(isc_task_t *task, isc_event_t *event) { + dns_fetchevent_t *devent = (dns_fetchevent_t *)event; + dns_fetch_t *fetch = NULL; + ns_client_t *client = NULL; + bool fetch_canceled = false; + bool fetch_answered = false; + bool client_shuttingdown = false; + isc_logcategory_t *logcategory = NS_LOGCATEGORY_QUERY_ERRORS; + isc_result_t result; + int errorloglevel; + query_ctx_t qctx; + + UNUSED(task); + + REQUIRE(event->ev_type == DNS_EVENT_FETCHDONE || + event->ev_type == DNS_EVENT_TRYSTALE); + + client = devent->ev_arg; + + REQUIRE(NS_CLIENT_VALID(client)); + REQUIRE(task == client->task); + REQUIRE(RECURSING(client)); + + CTRACE(ISC_LOG_DEBUG(3), "fetch_callback"); + + if (event->ev_type == DNS_EVENT_TRYSTALE) { + if (devent->result != ISC_R_CANCELED) { + query_lookup_stale(client); + } + isc_event_free(ISC_EVENT_PTR(&event)); + return; + } + /* + * We are resuming from recursion. Reset any attributes, options + * that a lookup due to stale-answer-client-timeout may have set. + */ + if (client->view->cachedb != NULL && client->view->recursion) { + client->query.attributes |= NS_QUERYATTR_RECURSIONOK; + } + client->query.fetchoptions &= ~DNS_FETCHOPT_TRYSTALE_ONTIMEOUT; + client->query.dboptions &= ~DNS_DBFIND_STALETIMEOUT; + client->nodetach = false; + + LOCK(&client->query.fetchlock); + INSIST(client->query.fetch == devent->fetch || + client->query.fetch == NULL); + if (QUERY_STALEPENDING(&client->query)) { + /* + * We've gotten an authoritative answer to a query that + * was left pending after a stale timeout. We don't need + * to do anything with it; free all the data and go home. + */ + client->query.fetch = NULL; + fetch_answered = true; + } else if (client->query.fetch != NULL) { + /* + * This is the fetch we've been waiting for. + */ + INSIST(devent->fetch == client->query.fetch); + client->query.fetch = NULL; + + /* + * Update client->now. + */ + isc_stdtime_get(&client->now); + } else { + /* + * This is a fetch completion event for a canceled fetch. + * Clean up and don't resume the find. + */ + fetch_canceled = true; + } + UNLOCK(&client->query.fetchlock); + + SAVE(fetch, devent->fetch); + + /* + * We're done recursing, detach from quota and unlink from + * the manager's recursing-clients list. + */ + + if (client->recursionquota != NULL) { + isc_quota_detach(&client->recursionquota); + ns_stats_decrement(client->sctx->nsstats, + ns_statscounter_recursclients); + } + + LOCK(&client->manager->reclock); + if (ISC_LINK_LINKED(client, rlink)) { + ISC_LIST_UNLINK(client->manager->recursing, client, rlink); + } + UNLOCK(&client->manager->reclock); + + isc_nmhandle_detach(&client->fetchhandle); + + client->query.attributes &= ~NS_QUERYATTR_RECURSING; + client->state = NS_CLIENTSTATE_WORKING; + + /* + * Initialize a new qctx and use it to either resume from + * recursion or clean up after cancelation. Transfer + * ownership of devent to the new qctx in the process. + */ + qctx_init(client, &devent, 0, &qctx); + + client_shuttingdown = ns_client_shuttingdown(client); + if (fetch_canceled || fetch_answered || client_shuttingdown) { + /* + * We've timed out or are shutting down. We can now + * free the event and other resources held by qctx, but + * don't call qctx_destroy() yet: it might destroy the + * client, which we still need for a moment. + */ + qctx_freedata(&qctx); + + /* + * Return an error to the client, or just drop. + */ + if (fetch_canceled) { + CTRACE(ISC_LOG_ERROR, "fetch cancelled"); + query_error(client, DNS_R_SERVFAIL, __LINE__); + } else { + query_next(client, ISC_R_CANCELED); + } + + /* + * Free any persistent plugin data that was allocated to + * service the client, then detach the client object. + */ + qctx.detach_client = true; + qctx_destroy(&qctx); + } else { + /* + * Resume the find process. + */ + query_trace(&qctx); + + result = query_resume(&qctx); + if (result != ISC_R_SUCCESS) { + if (result == DNS_R_SERVFAIL) { + errorloglevel = ISC_LOG_DEBUG(2); + } else { + errorloglevel = ISC_LOG_DEBUG(4); + } + if (isc_log_wouldlog(ns_lctx, errorloglevel)) { + dns_resolver_logfetch(fetch, ns_lctx, + logcategory, + NS_LOGMODULE_QUERY, + errorloglevel, false); + } + } + + qctx_destroy(&qctx); + } + + dns_resolver_destroyfetch(&fetch); +} + +/*% + * Check whether the recursion parameters in 'param' match the current query's + * recursion parameters provided in 'qtype', 'qname', and 'qdomain'. + */ +static bool +recparam_match(const ns_query_recparam_t *param, dns_rdatatype_t qtype, + const dns_name_t *qname, const dns_name_t *qdomain) { + REQUIRE(param != NULL); + + return (param->qtype == qtype && param->qname != NULL && + qname != NULL && param->qdomain != NULL && qdomain != NULL && + dns_name_equal(param->qname, qname) && + dns_name_equal(param->qdomain, qdomain)); +} + +/*% + * Update 'param' with current query's recursion parameters provided in + * 'qtype', 'qname', and 'qdomain'. + */ +static void +recparam_update(ns_query_recparam_t *param, dns_rdatatype_t qtype, + const dns_name_t *qname, const dns_name_t *qdomain) { + REQUIRE(param != NULL); + + param->qtype = qtype; + + if (qname == NULL) { + param->qname = NULL; + } else { + param->qname = dns_fixedname_initname(¶m->fqname); + dns_name_copy(qname, param->qname); + } + + if (qdomain == NULL) { + param->qdomain = NULL; + } else { + param->qdomain = dns_fixedname_initname(¶m->fqdomain); + dns_name_copy(qdomain, param->qdomain); + } +} +static atomic_uint_fast32_t last_soft, last_hard; + +/*% + * Check recursion quota before making the current client "recursing". + */ +static isc_result_t +check_recursionquota(ns_client_t *client) { + isc_result_t result = ISC_R_SUCCESS; + + /* + * 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(&client->sctx->recursionquota, + &client->recursionquota); + if (result == ISC_R_SUCCESS || result == ISC_R_SOFTQUOTA) { + ns_stats_increment(client->sctx->nsstats, + ns_statscounter_recursclients); + } + + if (result == ISC_R_SOFTQUOTA) { + isc_stdtime_t now; + isc_stdtime_get(&now); + if (now != atomic_load_relaxed(&last_soft)) { + atomic_store_relaxed(&last_soft, now); + ns_client_log(client, NS_LOGCATEGORY_CLIENT, + NS_LOGMODULE_QUERY, + ISC_LOG_WARNING, + "recursive-clients soft limit " + "exceeded (%u/%u/%u), " + "aborting oldest query", + isc_quota_getused( + client->recursionquota), + isc_quota_getsoft( + client->recursionquota), + isc_quota_getmax( + client->recursionquota)); + } + ns_client_killoldestquery(client); + result = ISC_R_SUCCESS; + } else if (result == ISC_R_QUOTA) { + isc_stdtime_t now; + isc_stdtime_get(&now); + if (now != atomic_load_relaxed(&last_hard)) { + ns_server_t *sctx = client->sctx; + atomic_store_relaxed(&last_hard, now); + ns_client_log( + client, NS_LOGCATEGORY_CLIENT, + NS_LOGMODULE_QUERY, ISC_LOG_WARNING, + "no more recursive clients " + "(%u/%u/%u): %s", + isc_quota_getused( + &sctx->recursionquota), + isc_quota_getsoft( + &sctx->recursionquota), + isc_quota_getmax(&sctx->recursionquota), + isc_result_totext(result)); + } + ns_client_killoldestquery(client); + } + if (result != ISC_R_SUCCESS) { + return (result); + } + + dns_message_clonebuffer(client->message); + ns_client_recursing(client); + } + + return (result); +} + +isc_result_t +ns_query_recurse(ns_client_t *client, dns_rdatatype_t qtype, dns_name_t *qname, + dns_name_t *qdomain, dns_rdataset_t *nameservers, + bool resuming) { + isc_result_t result; + dns_rdataset_t *rdataset, *sigrdataset; + isc_sockaddr_t *peeraddr = NULL; + + CTRACE(ISC_LOG_DEBUG(3), "ns_query_recurse"); + + /* + * Check recursion parameters from the previous query to see if they + * match. If not, update recursion parameters and proceed. + */ + if (recparam_match(&client->query.recparam, qtype, qname, qdomain)) { + ns_client_log(client, NS_LOGCATEGORY_CLIENT, NS_LOGMODULE_QUERY, + ISC_LOG_INFO, "recursion loop detected"); + return (ISC_R_ALREADYRUNNING); + } + + recparam_update(&client->query.recparam, qtype, qname, qdomain); + + if (!resuming) { + inc_stats(client, ns_statscounter_recursion); + } + + result = check_recursionquota(client); + if (result != ISC_R_SUCCESS) { + return (result); + } + + /* + * Invoke the resolver. + */ + REQUIRE(nameservers == NULL || nameservers->type == dns_rdatatype_ns); + REQUIRE(client->query.fetch == NULL); + + rdataset = ns_client_newrdataset(client); + if (rdataset == NULL) { + return (ISC_R_NOMEMORY); + } + + if (WANTDNSSEC(client)) { + sigrdataset = ns_client_newrdataset(client); + if (sigrdataset == NULL) { + ns_client_putrdataset(client, &rdataset); + return (ISC_R_NOMEMORY); + } + } else { + sigrdataset = NULL; + } + + if (!client->query.timerset) { + ns_client_settimeout(client, 60); + } + + if (!TCP(client)) { + peeraddr = &client->peeraddr; + } + + if (client->view->staleanswerclienttimeout > 0 && + client->view->staleanswerclienttimeout != (uint32_t)-1 && + dns_view_staleanswerenabled(client->view)) + { + client->query.fetchoptions |= DNS_FETCHOPT_TRYSTALE_ONTIMEOUT; + } + + isc_nmhandle_attach(client->handle, &client->fetchhandle); + result = dns_resolver_createfetch( + client->view->resolver, qname, qtype, qdomain, nameservers, + NULL, peeraddr, client->message->id, client->query.fetchoptions, + 0, NULL, client->task, fetch_callback, client, rdataset, + sigrdataset, &client->query.fetch); + if (result != ISC_R_SUCCESS) { + isc_nmhandle_detach(&client->fetchhandle); + ns_client_putrdataset(client, &rdataset); + if (sigrdataset != NULL) { + ns_client_putrdataset(client, &sigrdataset); + } + } + + /* + * We're now waiting for a fetch event. A client which is + * shutting down will not be destroyed until all the events + * have been received. + */ + + return (result); +} + +/*% + * Restores the query context after resuming from recursion, and + * continues the query processing if needed. + */ +static isc_result_t +query_resume(query_ctx_t *qctx) { + isc_result_t result = ISC_R_UNSET; + dns_name_t *tname; + isc_buffer_t b; +#ifdef WANT_QUERYTRACE + char mbuf[4 * DNS_NAME_FORMATSIZE]; + char qbuf[DNS_NAME_FORMATSIZE]; + char tbuf[DNS_RDATATYPE_FORMATSIZE]; +#endif /* ifdef WANT_QUERYTRACE */ + + CCTRACE(ISC_LOG_DEBUG(3), "query_resume"); + + CALL_HOOK(NS_QUERY_RESUME_BEGIN, qctx); + + qctx->want_restart = false; + + qctx->rpz_st = qctx->client->query.rpz_st; + if (qctx->rpz_st != NULL && + (qctx->rpz_st->state & DNS_RPZ_RECURSING) != 0) + { + CCTRACE(ISC_LOG_DEBUG(3), "resume from RPZ recursion"); +#ifdef WANT_QUERYTRACE + { + char pbuf[DNS_NAME_FORMATSIZE] = "<unset>"; + char fbuf[DNS_NAME_FORMATSIZE] = "<unset>"; + if (qctx->rpz_st->r_name != NULL) { + dns_name_format(qctx->rpz_st->r_name, qbuf, + sizeof(qbuf)); + } else { + snprintf(qbuf, sizeof(qbuf), "<unset>"); + } + if (qctx->rpz_st->p_name != NULL) { + dns_name_format(qctx->rpz_st->p_name, pbuf, + sizeof(pbuf)); + } + if (qctx->rpz_st->fname != NULL) { + dns_name_format(qctx->rpz_st->fname, fbuf, + sizeof(fbuf)); + } + + snprintf(mbuf, sizeof(mbuf) - 1, + "rpz rname:%s, pname:%s, qctx->fname:%s", qbuf, + pbuf, fbuf); + CCTRACE(ISC_LOG_DEBUG(3), mbuf); + } +#endif /* ifdef WANT_QUERYTRACE */ + + qctx->is_zone = qctx->rpz_st->q.is_zone; + qctx->authoritative = qctx->rpz_st->q.authoritative; + RESTORE(qctx->zone, qctx->rpz_st->q.zone); + RESTORE(qctx->node, qctx->rpz_st->q.node); + RESTORE(qctx->db, qctx->rpz_st->q.db); + RESTORE(qctx->rdataset, qctx->rpz_st->q.rdataset); + RESTORE(qctx->sigrdataset, qctx->rpz_st->q.sigrdataset); + qctx->qtype = qctx->rpz_st->q.qtype; + + if (qctx->event->node != NULL) { + dns_db_detachnode(qctx->event->db, &qctx->event->node); + } + SAVE(qctx->rpz_st->r.db, qctx->event->db); + qctx->rpz_st->r.r_type = qctx->event->qtype; + SAVE(qctx->rpz_st->r.r_rdataset, qctx->event->rdataset); + ns_client_putrdataset(qctx->client, &qctx->event->sigrdataset); + } else if (REDIRECT(qctx->client)) { + /* + * Restore saved state. + */ + CCTRACE(ISC_LOG_DEBUG(3), "resume from redirect recursion"); +#ifdef WANT_QUERYTRACE + dns_name_format(qctx->client->query.redirect.fname, qbuf, + sizeof(qbuf)); + dns_rdatatype_format(qctx->client->query.redirect.qtype, tbuf, + sizeof(tbuf)); + snprintf(mbuf, sizeof(mbuf) - 1, + "redirect qctx->fname:%s, qtype:%s, auth:%d", qbuf, + tbuf, qctx->client->query.redirect.authoritative); + CCTRACE(ISC_LOG_DEBUG(3), mbuf); +#endif /* ifdef WANT_QUERYTRACE */ + qctx->qtype = qctx->client->query.redirect.qtype; + INSIST(qctx->client->query.redirect.rdataset != NULL); + RESTORE(qctx->rdataset, qctx->client->query.redirect.rdataset); + RESTORE(qctx->sigrdataset, + qctx->client->query.redirect.sigrdataset); + RESTORE(qctx->db, qctx->client->query.redirect.db); + RESTORE(qctx->node, qctx->client->query.redirect.node); + RESTORE(qctx->zone, qctx->client->query.redirect.zone); + qctx->authoritative = + qctx->client->query.redirect.authoritative; + + /* + * Free resources used while recursing. + */ + ns_client_putrdataset(qctx->client, &qctx->event->rdataset); + ns_client_putrdataset(qctx->client, &qctx->event->sigrdataset); + if (qctx->event->node != NULL) { + dns_db_detachnode(qctx->event->db, &qctx->event->node); + } + if (qctx->event->db != NULL) { + dns_db_detach(&qctx->event->db); + } + } else { + CCTRACE(ISC_LOG_DEBUG(3), "resume from normal recursion"); + qctx->authoritative = false; + + qctx->qtype = qctx->event->qtype; + SAVE(qctx->db, qctx->event->db); + SAVE(qctx->node, qctx->event->node); + SAVE(qctx->rdataset, qctx->event->rdataset); + SAVE(qctx->sigrdataset, qctx->event->sigrdataset); + } + INSIST(qctx->rdataset != NULL); + + if (qctx->qtype == dns_rdatatype_rrsig || + qctx->qtype == dns_rdatatype_sig) + { + qctx->type = dns_rdatatype_any; + } else { + qctx->type = qctx->qtype; + } + + CALL_HOOK(NS_QUERY_RESUME_RESTORED, qctx); + + if (DNS64(qctx->client)) { + qctx->client->query.attributes &= ~NS_QUERYATTR_DNS64; + qctx->dns64 = true; + } + + if (DNS64EXCLUDE(qctx->client)) { + qctx->client->query.attributes &= ~NS_QUERYATTR_DNS64EXCLUDE; + qctx->dns64_exclude = true; + } + + if (qctx->rpz_st != NULL && + (qctx->rpz_st->state & DNS_RPZ_RECURSING) != 0) + { + /* + * Has response policy changed out from under us? + */ + if (qctx->rpz_st->rpz_ver != qctx->view->rpzs->rpz_ver) { + ns_client_log(qctx->client, NS_LOGCATEGORY_CLIENT, + NS_LOGMODULE_QUERY, DNS_RPZ_INFO_LEVEL, + "query_resume: RPZ settings " + "out of date " + "(rpz_ver %d, expected %d)", + qctx->view->rpzs->rpz_ver, + qctx->rpz_st->rpz_ver); + QUERY_ERROR(qctx, DNS_R_SERVFAIL); + return (ns_query_done(qctx)); + } + } + + /* + * We'll need some resources... + */ + qctx->dbuf = ns_client_getnamebuf(qctx->client); + if (qctx->dbuf == NULL) { + CCTRACE(ISC_LOG_ERROR, "query_resume: ns_client_getnamebuf " + "failed (1)"); + QUERY_ERROR(qctx, ISC_R_NOMEMORY); + return (ns_query_done(qctx)); + } + + qctx->fname = ns_client_newname(qctx->client, qctx->dbuf, &b); + if (qctx->fname == NULL) { + CCTRACE(ISC_LOG_ERROR, "query_resume: ns_client_newname failed " + "(1)"); + QUERY_ERROR(qctx, ISC_R_NOMEMORY); + return (ns_query_done(qctx)); + } + + if (qctx->rpz_st != NULL && + (qctx->rpz_st->state & DNS_RPZ_RECURSING) != 0) + { + tname = qctx->rpz_st->fname; + } else if (REDIRECT(qctx->client)) { + tname = qctx->client->query.redirect.fname; + } else { + tname = qctx->event->foundname; + } + + dns_name_copy(tname, qctx->fname); + + if (qctx->rpz_st != NULL && + (qctx->rpz_st->state & DNS_RPZ_RECURSING) != 0) + { + qctx->rpz_st->r.r_result = qctx->event->result; + result = qctx->rpz_st->q.result; + free_devent(qctx->client, ISC_EVENT_PTR(&qctx->event), + &qctx->event); + } else if (REDIRECT(qctx->client)) { + result = qctx->client->query.redirect.result; + } else { + result = qctx->event->result; + } + + qctx->resuming = true; + + return (query_gotanswer(qctx, result)); + +cleanup: + return (result); +} + +static void +query_hookresume(isc_task_t *task, isc_event_t *event) { + ns_hook_resevent_t *rev = (ns_hook_resevent_t *)event; + ns_hookasync_t *hctx = NULL; + ns_client_t *client = rev->ev_arg; + query_ctx_t *qctx = rev->saved_qctx; + bool canceled; + + CTRACE(ISC_LOG_DEBUG(3), "query_hookresume"); + + REQUIRE(NS_CLIENT_VALID(client)); + REQUIRE(task == client->task); + REQUIRE(event->ev_type == NS_EVENT_HOOKASYNCDONE); + + LOCK(&client->query.fetchlock); + if (client->query.hookactx != NULL) { + INSIST(rev->ctx == client->query.hookactx); + client->query.hookactx = NULL; + canceled = false; + isc_stdtime_get(&client->now); + } else { + canceled = true; + } + UNLOCK(&client->query.fetchlock); + SAVE(hctx, rev->ctx); + + if (client->recursionquota != NULL) { + isc_quota_detach(&client->recursionquota); + ns_stats_decrement(client->sctx->nsstats, + ns_statscounter_recursclients); + } + + LOCK(&client->manager->reclock); + if (ISC_LINK_LINKED(client, rlink)) { + ISC_LIST_UNLINK(client->manager->recursing, client, rlink); + } + UNLOCK(&client->manager->reclock); + + /* + * This event is running under a client task, so it's safe to detach + * the fetch handle. And it should be done before resuming query + * processing below, since that may trigger another recursion or + * asynchronous hook event. + */ + isc_nmhandle_detach(&client->fetchhandle); + + client->state = NS_CLIENTSTATE_WORKING; + + if (canceled) { + /* + * Note: unlike fetch_callback, this function doesn't bother + * to check the 'shutdown' condition, as that doesn't seem to + * happen in the latest implementation. + */ + query_error(client, DNS_R_SERVFAIL, __LINE__); + + /* + * There's no other place to free/release any data maintained + * in qctx. We need to do it here to prevent leak. + */ + qctx_clean(qctx); + qctx_freedata(qctx); + + /* + * As we're almost done with this client, make sure any internal + * resource for hooks will be released (if necessary) via the + * QCTX_DESTROYED hook. + */ + qctx->detach_client = true; + } else { + switch (rev->hookpoint) { + case NS_QUERY_SETUP: + (void)query_setup(client, qctx->qtype); + break; + case NS_QUERY_START_BEGIN: + (void)ns__query_start(qctx); + break; + case NS_QUERY_LOOKUP_BEGIN: + (void)query_lookup(qctx); + break; + case NS_QUERY_RESUME_BEGIN: + case NS_QUERY_RESUME_RESTORED: + (void)query_resume(qctx); + break; + case NS_QUERY_GOT_ANSWER_BEGIN: + (void)query_gotanswer(qctx, rev->origresult); + break; + case NS_QUERY_RESPOND_ANY_BEGIN: + (void)query_respond_any(qctx); + break; + case NS_QUERY_ADDANSWER_BEGIN: + (void)query_addanswer(qctx); + break; + case NS_QUERY_NOTFOUND_BEGIN: + (void)query_notfound(qctx); + break; + case NS_QUERY_PREP_DELEGATION_BEGIN: + (void)query_prepare_delegation_response(qctx); + break; + case NS_QUERY_ZONE_DELEGATION_BEGIN: + (void)query_zone_delegation(qctx); + break; + case NS_QUERY_DELEGATION_BEGIN: + (void)query_delegation(qctx); + break; + case NS_QUERY_DELEGATION_RECURSE_BEGIN: + (void)query_delegation_recurse(qctx); + break; + case NS_QUERY_NODATA_BEGIN: + (void)query_nodata(qctx, rev->origresult); + break; + case NS_QUERY_NXDOMAIN_BEGIN: + (void)query_nxdomain(qctx, rev->origresult); + break; + case NS_QUERY_NCACHE_BEGIN: + (void)query_ncache(qctx, rev->origresult); + break; + case NS_QUERY_CNAME_BEGIN: + (void)query_cname(qctx); + break; + case NS_QUERY_DNAME_BEGIN: + (void)query_dname(qctx); + break; + case NS_QUERY_RESPOND_BEGIN: + (void)query_respond(qctx); + break; + case NS_QUERY_PREP_RESPONSE_BEGIN: + (void)query_prepresponse(qctx); + break; + case NS_QUERY_DONE_BEGIN: + case NS_QUERY_DONE_SEND: + (void)ns_query_done(qctx); + break; + + /* Not all hookpoints can use recursion. Catch violations */ + case NS_QUERY_RESPOND_ANY_FOUND: /* due to side effect */ + case NS_QUERY_NOTFOUND_RECURSE: /* in recursion */ + case NS_QUERY_ZEROTTL_RECURSE: /* in recursion */ + default: /* catch-all just in case */ + INSIST(false); + } + } + + hctx->destroy(&hctx); + qctx_destroy(qctx); + isc_mem_put(client->mctx, qctx, sizeof(*qctx)); + isc_event_free(&event); +} + +isc_result_t +ns_query_hookasync(query_ctx_t *qctx, ns_query_starthookasync_t runasync, + void *arg) { + isc_result_t result; + ns_client_t *client = qctx->client; + query_ctx_t *saved_qctx = NULL; + + CTRACE(ISC_LOG_DEBUG(3), "ns_query_hookasync"); + + REQUIRE(NS_CLIENT_VALID(client)); + REQUIRE(client->query.hookactx == NULL); + REQUIRE(client->query.fetch == NULL); + + result = check_recursionquota(client); + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + + saved_qctx = isc_mem_get(client->mctx, sizeof(*saved_qctx)); + qctx_save(qctx, saved_qctx); + result = runasync(saved_qctx, client->mctx, arg, client->task, + query_hookresume, client, &client->query.hookactx); + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + + /* + * Typically the runasync() function will trigger recursion, but + * there is no need to set NS_QUERYATTR_RECURSING. The calling hook + * is expected to return NS_HOOK_RETURN, and the RECURSING + * attribute won't be checked anywhere. + * + * Hook-based asynchronous processing cannot coincide with normal + * recursion, so we can safely use fetchhandle here. Unlike in + * ns_query_recurse(), we attach to the handle only if 'runasync' + * succeeds. It should be safe since we're either in the client + * task or pausing it. + */ + isc_nmhandle_attach(client->handle, &client->fetchhandle); + return (ISC_R_SUCCESS); + +cleanup: + /* + * If we fail, send SERVFAIL now. It may be better to let the caller + * decide what to do on failure of this function, but hooks don't have + * access to query_error(). + */ + query_error(client, DNS_R_SERVFAIL, __LINE__); + + /* + * Free all resource related to the query and set detach_client, + * similar to the cancel case of query_hookresume; the callers will + * simply return on failure of this function, so there's no other + * place for this to prevent leak. + */ + if (saved_qctx != NULL) { + qctx_clean(saved_qctx); + qctx_freedata(saved_qctx); + qctx_destroy(saved_qctx); + isc_mem_put(client->mctx, saved_qctx, sizeof(*saved_qctx)); + } + qctx->detach_client = true; + return (result); +} + +/*% + * If the query is recursive, check the SERVFAIL cache to see whether + * identical queries have failed recently. If we find a match, and it was + * from a query with CD=1, *or* if the current query has CD=0, then we just + * return SERVFAIL again. This prevents a validation failure from eliciting a + * SERVFAIL response to a CD=1 query. + */ +isc_result_t +ns__query_sfcache(query_ctx_t *qctx) { + bool failcache; + uint32_t flags; + + /* + * The SERVFAIL cache doesn't apply to authoritative queries. + */ + if (!RECURSIONOK(qctx->client)) { + return (ISC_R_COMPLETE); + } + + flags = 0; +#ifdef ENABLE_AFL + if (qctx->client->sctx->fuzztype == isc_fuzz_resolver) { + failcache = false; + } else { + failcache = dns_badcache_find( + qctx->view->failcache, qctx->client->query.qname, + qctx->qtype, &flags, &qctx->client->tnow); + } +#else /* ifdef ENABLE_AFL */ + failcache = dns_badcache_find(qctx->view->failcache, + qctx->client->query.qname, qctx->qtype, + &flags, &qctx->client->tnow); +#endif /* ifdef ENABLE_AFL */ + if (failcache && + (((flags & NS_FAILCACHE_CD) != 0) || + ((qctx->client->message->flags & DNS_MESSAGEFLAG_CD) == 0))) + { + if (isc_log_wouldlog(ns_lctx, ISC_LOG_DEBUG(1))) { + char namebuf[DNS_NAME_FORMATSIZE]; + char typebuf[DNS_RDATATYPE_FORMATSIZE]; + + dns_name_format(qctx->client->query.qname, namebuf, + sizeof(namebuf)); + dns_rdatatype_format(qctx->qtype, typebuf, + sizeof(typebuf)); + ns_client_log(qctx->client, NS_LOGCATEGORY_CLIENT, + NS_LOGMODULE_QUERY, ISC_LOG_DEBUG(1), + "servfail cache hit %s/%s (%s)", namebuf, + typebuf, + ((flags & NS_FAILCACHE_CD) != 0) ? "CD=1" + : "CD=" + "0"); + } + + qctx->client->attributes |= NS_CLIENTATTR_NOSETFC; + QUERY_ERROR(qctx, DNS_R_SERVFAIL); + return (ns_query_done(qctx)); + } + + return (ISC_R_COMPLETE); +} + +/*% + * Handle response rate limiting (RRL). + */ +static isc_result_t +query_checkrrl(query_ctx_t *qctx, isc_result_t result) { + /* + * Rate limit these responses to this client. + * Do not delay counting and handling obvious referrals, + * since those won't come here again. + * Delay handling delegations for which we are certain to recurse and + * return here (DNS_R_DELEGATION, not a child of one of our + * own zones, and recursion enabled) + * Don't mess with responses rewritten by RPZ + * Count each response at most once. + */ + + /* + * XXXMPA the rrl system tests fails sometimes and RRL_CHECKED + * is set when we are called the second time preventing the + * response being dropped. + */ + ns_client_log( + qctx->client, DNS_LOGCATEGORY_RRL, NS_LOGMODULE_QUERY, + ISC_LOG_DEBUG(99), + "rrl=%p, HAVECOOKIE=%u, result=%s, " + "fname=%p(%u), is_zone=%u, RECURSIONOK=%u, " + "query.rpz_st=%p(%u), RRL_CHECKED=%u\n", + qctx->client->view->rrl, HAVECOOKIE(qctx->client), + isc_result_toid(result), qctx->fname, + qctx->fname != NULL ? dns_name_isabsolute(qctx->fname) : 0, + qctx->is_zone, RECURSIONOK(qctx->client), + qctx->client->query.rpz_st, + qctx->client->query.rpz_st != NULL + ? ((qctx->client->query.rpz_st->state & + DNS_RPZ_REWRITTEN) != 0) + : 0, + (qctx->client->query.attributes & NS_QUERYATTR_RRL_CHECKED) != + 0); + + if (qctx->view->rrl != NULL && !HAVECOOKIE(qctx->client) && + ((qctx->fname != NULL && dns_name_isabsolute(qctx->fname)) || + (result == ISC_R_NOTFOUND && !RECURSIONOK(qctx->client))) && + !(result == DNS_R_DELEGATION && !qctx->is_zone && + RECURSIONOK(qctx->client)) && + (qctx->client->query.rpz_st == NULL || + (qctx->client->query.rpz_st->state & DNS_RPZ_REWRITTEN) == 0) && + (qctx->client->query.attributes & NS_QUERYATTR_RRL_CHECKED) == 0) + { + dns_rdataset_t nc_rdataset; + bool wouldlog; + dns_fixedname_t fixed; + const dns_name_t *constname; + char log_buf[DNS_RRL_LOG_BUF_LEN]; + isc_result_t nc_result, resp_result; + dns_rrl_result_t rrl_result; + + qctx->client->query.attributes |= NS_QUERYATTR_RRL_CHECKED; + + wouldlog = isc_log_wouldlog(ns_lctx, DNS_RRL_LOG_DROP); + constname = qctx->fname; + if (result == DNS_R_NXDOMAIN) { + /* + * Use the database origin name to rate limit NXDOMAIN + */ + if (qctx->db != NULL) { + constname = dns_db_origin(qctx->db); + } + resp_result = result; + } else if (result == DNS_R_NCACHENXDOMAIN && + qctx->rdataset != NULL && + dns_rdataset_isassociated(qctx->rdataset) && + (qctx->rdataset->attributes & + DNS_RDATASETATTR_NEGATIVE) != 0) + { + /* + * Try to use owner name in the negative cache SOA. + */ + dns_fixedname_init(&fixed); + dns_rdataset_init(&nc_rdataset); + for (nc_result = dns_rdataset_first(qctx->rdataset); + nc_result == ISC_R_SUCCESS; + nc_result = dns_rdataset_next(qctx->rdataset)) + { + dns_ncache_current(qctx->rdataset, + dns_fixedname_name(&fixed), + &nc_rdataset); + if (nc_rdataset.type == dns_rdatatype_soa) { + dns_rdataset_disassociate(&nc_rdataset); + constname = dns_fixedname_name(&fixed); + break; + } + dns_rdataset_disassociate(&nc_rdataset); + } + resp_result = DNS_R_NXDOMAIN; + } else if (result == DNS_R_NXRRSET || result == DNS_R_EMPTYNAME) + { + resp_result = DNS_R_NXRRSET; + } else if (result == DNS_R_DELEGATION) { + resp_result = result; + } else if (result == ISC_R_NOTFOUND) { + /* + * Handle referral to ".", including when recursion + * is off or not requested and the hints have not + * been loaded. + */ + constname = dns_rootname; + resp_result = DNS_R_DELEGATION; + } else { + resp_result = ISC_R_SUCCESS; + } + + rrl_result = dns_rrl( + qctx->view, qctx->zone, &qctx->client->peeraddr, + TCP(qctx->client), qctx->client->message->rdclass, + qctx->qtype, constname, resp_result, qctx->client->now, + wouldlog, log_buf, sizeof(log_buf)); + if (rrl_result != DNS_RRL_RESULT_OK) { + /* + * Log dropped or slipped responses in the query + * category so that requests are not silently lost. + * Starts of rate-limited bursts are logged in + * DNS_LOGCATEGORY_RRL. + * + * Dropped responses are counted with dropped queries + * in QryDropped while slipped responses are counted + * with other truncated responses in RespTruncated. + */ + if (wouldlog) { + ns_client_log(qctx->client, DNS_LOGCATEGORY_RRL, + NS_LOGMODULE_QUERY, + DNS_RRL_LOG_DROP, "%s", log_buf); + } + + if (!qctx->view->rrl->log_only) { + if (rrl_result == DNS_RRL_RESULT_DROP) { + /* + * These will also be counted in + * ns_statscounter_dropped + */ + inc_stats(qctx->client, + ns_statscounter_ratedropped); + QUERY_ERROR(qctx, DNS_R_DROP); + } else { + /* + * These will also be counted in + * ns_statscounter_truncatedresp + */ + inc_stats(qctx->client, + ns_statscounter_rateslipped); + if (WANTCOOKIE(qctx->client)) { + qctx->client->message->flags &= + ~DNS_MESSAGEFLAG_AA; + qctx->client->message->flags &= + ~DNS_MESSAGEFLAG_AD; + qctx->client->message->rcode = + dns_rcode_badcookie; + } else { + qctx->client->message->flags |= + DNS_MESSAGEFLAG_TC; + if (resp_result == + DNS_R_NXDOMAIN) + { + qctx->client->message + ->rcode = + dns_rcode_nxdomain; + } + } + } + return (DNS_R_DROP); + } + } + } + + return (ISC_R_SUCCESS); +} + +/*% + * Do any RPZ rewriting that may be needed for this query. + */ +static isc_result_t +query_checkrpz(query_ctx_t *qctx, isc_result_t result) { + isc_result_t rresult; + + CCTRACE(ISC_LOG_DEBUG(3), "query_checkrpz"); + + rresult = rpz_rewrite(qctx->client, qctx->qtype, result, qctx->resuming, + qctx->rdataset, qctx->sigrdataset); + qctx->rpz_st = qctx->client->query.rpz_st; + switch (rresult) { + case ISC_R_SUCCESS: + break; + case ISC_R_NOTFOUND: + case DNS_R_DISALLOWED: + return (result); + case DNS_R_DELEGATION: + /* + * recursing for NS names or addresses, + * so save the main query state + */ + INSIST(!RECURSING(qctx->client)); + qctx->rpz_st->q.qtype = qctx->qtype; + qctx->rpz_st->q.is_zone = qctx->is_zone; + qctx->rpz_st->q.authoritative = qctx->authoritative; + SAVE(qctx->rpz_st->q.zone, qctx->zone); + SAVE(qctx->rpz_st->q.db, qctx->db); + SAVE(qctx->rpz_st->q.node, qctx->node); + SAVE(qctx->rpz_st->q.rdataset, qctx->rdataset); + SAVE(qctx->rpz_st->q.sigrdataset, qctx->sigrdataset); + dns_name_copy(qctx->fname, qctx->rpz_st->fname); + qctx->rpz_st->q.result = result; + qctx->client->query.attributes |= NS_QUERYATTR_RECURSING; + return (ISC_R_COMPLETE); + default: + QUERY_ERROR(qctx, rresult); + return (ISC_R_COMPLETE); + } + + if (qctx->rpz_st->m.policy != DNS_RPZ_POLICY_MISS) { + qctx->rpz_st->state |= DNS_RPZ_REWRITTEN; + } + + if (qctx->rpz_st->m.policy != DNS_RPZ_POLICY_MISS && + qctx->rpz_st->m.policy != DNS_RPZ_POLICY_PASSTHRU && + (qctx->rpz_st->m.policy != DNS_RPZ_POLICY_TCP_ONLY || + !TCP(qctx->client)) && + qctx->rpz_st->m.policy != DNS_RPZ_POLICY_ERROR) + { + /* + * We got a hit and are going to answer with our + * fiction. Ensure that we answer with the name + * we looked up even if we were stopped short + * in recursion or for a deferral. + */ + dns_name_copy(qctx->client->query.qname, qctx->fname); + rpz_clean(&qctx->zone, &qctx->db, &qctx->node, NULL); + if (qctx->rpz_st->m.rdataset != NULL) { + ns_client_putrdataset(qctx->client, &qctx->rdataset); + RESTORE(qctx->rdataset, qctx->rpz_st->m.rdataset); + } else { + qctx_clean(qctx); + } + qctx->version = NULL; + + RESTORE(qctx->node, qctx->rpz_st->m.node); + RESTORE(qctx->db, qctx->rpz_st->m.db); + RESTORE(qctx->version, qctx->rpz_st->m.version); + RESTORE(qctx->zone, qctx->rpz_st->m.zone); + + /* + * Add SOA record to additional section + */ + if (qctx->rpz_st->m.rpz->addsoa) { + bool override_ttl = + dns_rdataset_isassociated(qctx->rdataset); + rresult = query_addsoa(qctx, override_ttl, + DNS_SECTION_ADDITIONAL); + if (rresult != ISC_R_SUCCESS) { + QUERY_ERROR(qctx, result); + return (ISC_R_COMPLETE); + } + } + + switch (qctx->rpz_st->m.policy) { + case DNS_RPZ_POLICY_TCP_ONLY: + qctx->client->message->flags |= DNS_MESSAGEFLAG_TC; + if (result == DNS_R_NXDOMAIN || + result == DNS_R_NCACHENXDOMAIN) + { + qctx->client->message->rcode = + dns_rcode_nxdomain; + } + rpz_log_rewrite(qctx->client, false, + qctx->rpz_st->m.policy, + qctx->rpz_st->m.type, qctx->zone, + qctx->rpz_st->p_name, NULL, + qctx->rpz_st->m.rpz->num); + return (ISC_R_COMPLETE); + case DNS_RPZ_POLICY_DROP: + QUERY_ERROR(qctx, DNS_R_DROP); + rpz_log_rewrite(qctx->client, false, + qctx->rpz_st->m.policy, + qctx->rpz_st->m.type, qctx->zone, + qctx->rpz_st->p_name, NULL, + qctx->rpz_st->m.rpz->num); + return (ISC_R_COMPLETE); + case DNS_RPZ_POLICY_NXDOMAIN: + result = DNS_R_NXDOMAIN; + qctx->nxrewrite = true; + qctx->rpz = true; + break; + case DNS_RPZ_POLICY_NODATA: + qctx->nxrewrite = true; + FALLTHROUGH; + case DNS_RPZ_POLICY_DNS64: + result = DNS_R_NXRRSET; + qctx->rpz = true; + break; + case DNS_RPZ_POLICY_RECORD: + result = qctx->rpz_st->m.result; + if (qctx->qtype == dns_rdatatype_any && + result != DNS_R_CNAME) + { + /* + * We will add all of the rdatasets of + * the node by iterating later, + * and set the TTL then. + */ + if (dns_rdataset_isassociated(qctx->rdataset)) { + dns_rdataset_disassociate( + qctx->rdataset); + } + } else { + /* + * We will add this rdataset. + */ + qctx->rdataset->ttl = + ISC_MIN(qctx->rdataset->ttl, + qctx->rpz_st->m.ttl); + } + qctx->rpz = true; + break; + case DNS_RPZ_POLICY_WILDCNAME: { + dns_rdata_t rdata = DNS_RDATA_INIT; + dns_rdata_cname_t cname; + result = dns_rdataset_first(qctx->rdataset); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + dns_rdataset_current(qctx->rdataset, &rdata); + result = dns_rdata_tostruct(&rdata, &cname, NULL); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + dns_rdata_reset(&rdata); + result = query_rpzcname(qctx, &cname.cname); + if (result != ISC_R_SUCCESS) { + return (ISC_R_COMPLETE); + } + qctx->fname = NULL; + qctx->want_restart = true; + return (ISC_R_COMPLETE); + } + case DNS_RPZ_POLICY_CNAME: + /* + * Add overriding CNAME from a named.conf + * response-policy statement + */ + result = query_rpzcname(qctx, + &qctx->rpz_st->m.rpz->cname); + if (result != ISC_R_SUCCESS) { + return (ISC_R_COMPLETE); + } + qctx->fname = NULL; + qctx->want_restart = true; + return (ISC_R_COMPLETE); + default: + UNREACHABLE(); + } + + /* + * Turn off DNSSEC because the results of a + * response policy zone cannot verify. + */ + qctx->client->attributes &= ~(NS_CLIENTATTR_WANTDNSSEC | + NS_CLIENTATTR_WANTAD); + qctx->client->message->flags &= ~DNS_MESSAGEFLAG_AD; + ns_client_putrdataset(qctx->client, &qctx->sigrdataset); + qctx->rpz_st->q.is_zone = qctx->is_zone; + qctx->is_zone = true; + rpz_log_rewrite(qctx->client, false, qctx->rpz_st->m.policy, + qctx->rpz_st->m.type, qctx->zone, + qctx->rpz_st->p_name, NULL, + qctx->rpz_st->m.rpz->num); + } + + return (result); +} + +/*% + * Add a CNAME to a query response, including translating foo.evil.com and + * *.evil.com CNAME *.example.com + * to + * foo.evil.com CNAME foo.evil.com.example.com + */ +static isc_result_t +query_rpzcname(query_ctx_t *qctx, dns_name_t *cname) { + ns_client_t *client; + dns_fixedname_t prefix, suffix; + unsigned int labels; + isc_result_t result; + + REQUIRE(qctx != NULL && qctx->client != NULL); + + client = qctx->client; + + CTRACE(ISC_LOG_DEBUG(3), "query_rpzcname"); + + labels = dns_name_countlabels(cname); + if (labels > 2 && dns_name_iswildcard(cname)) { + dns_fixedname_init(&prefix); + dns_name_split(client->query.qname, 1, + dns_fixedname_name(&prefix), NULL); + dns_fixedname_init(&suffix); + dns_name_split(cname, labels - 1, NULL, + dns_fixedname_name(&suffix)); + result = dns_name_concatenate(dns_fixedname_name(&prefix), + dns_fixedname_name(&suffix), + qctx->fname, NULL); + if (result == DNS_R_NAMETOOLONG) { + client->message->rcode = dns_rcode_yxdomain; + } else if (result != ISC_R_SUCCESS) { + return (result); + } + } else { + dns_name_copy(cname, qctx->fname); + } + + ns_client_keepname(client, qctx->fname, qctx->dbuf); + result = query_addcname(qctx, dns_trust_authanswer, + qctx->rpz_st->m.ttl); + if (result != ISC_R_SUCCESS) { + return (result); + } + + rpz_log_rewrite(client, false, qctx->rpz_st->m.policy, + qctx->rpz_st->m.type, qctx->rpz_st->m.zone, + qctx->rpz_st->p_name, qctx->fname, + qctx->rpz_st->m.rpz->num); + + ns_client_qnamereplace(client, qctx->fname); + + /* + * Turn off DNSSEC because the results of a + * response policy zone cannot verify. + */ + client->attributes &= ~(NS_CLIENTATTR_WANTDNSSEC | + NS_CLIENTATTR_WANTAD); + + return (ISC_R_SUCCESS); +} + +/*% + * Check the configured trust anchors for a root zone trust anchor + * with a key id that matches qctx->client->query.root_key_sentinel_keyid. + * + * Return true when found, otherwise return false. + */ +static bool +has_ta(query_ctx_t *qctx) { + dns_keytable_t *keytable = NULL; + dns_keynode_t *keynode = NULL; + dns_rdataset_t dsset; + dns_keytag_t sentinel = qctx->client->query.root_key_sentinel_keyid; + isc_result_t result; + + result = dns_view_getsecroots(qctx->view, &keytable); + if (result != ISC_R_SUCCESS) { + return (false); + } + + result = dns_keytable_find(keytable, dns_rootname, &keynode); + if (result != ISC_R_SUCCESS) { + if (keynode != NULL) { + dns_keytable_detachkeynode(keytable, &keynode); + } + dns_keytable_detach(&keytable); + return (false); + } + + dns_rdataset_init(&dsset); + if (dns_keynode_dsset(keynode, &dsset)) { + for (result = dns_rdataset_first(&dsset); + result == ISC_R_SUCCESS; + result = dns_rdataset_next(&dsset)) + { + dns_rdata_t rdata = DNS_RDATA_INIT; + dns_rdata_ds_t ds; + + dns_rdata_reset(&rdata); + dns_rdataset_current(&dsset, &rdata); + result = dns_rdata_tostruct(&rdata, &ds, NULL); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + if (ds.key_tag == sentinel) { + dns_keytable_detachkeynode(keytable, &keynode); + dns_keytable_detach(&keytable); + dns_rdataset_disassociate(&dsset); + return (true); + } + } + dns_rdataset_disassociate(&dsset); + } + + if (keynode != NULL) { + dns_keytable_detachkeynode(keytable, &keynode); + } + + dns_keytable_detach(&keytable); + + return (false); +} + +/*% + * Check if a root key sentinel SERVFAIL should be returned. + */ +static bool +root_key_sentinel_return_servfail(query_ctx_t *qctx, isc_result_t result) { + /* + * Are we looking at a "root-key-sentinel" query? + */ + if (!qctx->client->query.root_key_sentinel_is_ta && + !qctx->client->query.root_key_sentinel_not_ta) + { + return (false); + } + + /* + * We only care about the query if 'result' indicates we have a cached + * answer. + */ + switch (result) { + case ISC_R_SUCCESS: + case DNS_R_CNAME: + case DNS_R_DNAME: + case DNS_R_NCACHENXDOMAIN: + case DNS_R_NCACHENXRRSET: + break; + default: + return (false); + } + + /* + * Do we meet the specified conditions to return SERVFAIL? + */ + if (!qctx->is_zone && qctx->rdataset->trust == dns_trust_secure && + ((qctx->client->query.root_key_sentinel_is_ta && !has_ta(qctx)) || + (qctx->client->query.root_key_sentinel_not_ta && has_ta(qctx)))) + { + return (true); + } + + /* + * As special processing may only be triggered by the original QNAME, + * disable it after following a CNAME/DNAME. + */ + qctx->client->query.root_key_sentinel_is_ta = false; + qctx->client->query.root_key_sentinel_not_ta = false; + + return (false); +} + +/*% + * If serving stale answers is allowed, set up 'qctx' to look for one and + * return true; otherwise, return false. + */ +static bool +query_usestale(query_ctx_t *qctx, isc_result_t result) { + if ((qctx->client->query.dboptions & DNS_DBFIND_STALEOK) != 0) { + /* + * Query was already using stale, if that didn't work the + * last time, it won't work this time either. + */ + return (false); + } + + if (qctx->refresh_rrset) { + /* + * This is a refreshing query, we have already prioritized + * stale data, so don't enable serve-stale again. + */ + return (false); + } + + if (result == DNS_R_DUPLICATE || result == DNS_R_DROP || + result == ISC_R_ALREADYRUNNING) + { + /* + * Don't enable serve-stale if the result signals a duplicate + * query or a query that is being dropped or can't proceed + * because of a recursion loop. + */ + return (false); + } + + qctx_clean(qctx); + qctx_freedata(qctx); + + if (dns_view_staleanswerenabled(qctx->client->view)) { + dns_db_attach(qctx->client->view->cachedb, &qctx->db); + qctx->version = NULL; + qctx->client->query.dboptions |= DNS_DBFIND_STALEOK; + if (qctx->client->query.fetch != NULL) { + dns_resolver_destroyfetch(&qctx->client->query.fetch); + } + + /* + * Start the stale-refresh-time window in case there was a + * resolver query timeout. + */ + if (qctx->resuming && result == ISC_R_TIMEDOUT) { + qctx->client->query.dboptions |= DNS_DBFIND_STALESTART; + } + return (true); + } + + return (false); +} + +/*% + * Continue after doing a database lookup or returning from + * recursion, and call out to the next function depending on the + * result from the search. + */ +static isc_result_t +query_gotanswer(query_ctx_t *qctx, isc_result_t res) { + isc_result_t result = res; + char errmsg[256]; + + CCTRACE(ISC_LOG_DEBUG(3), "query_gotanswer"); + + CALL_HOOK(NS_QUERY_GOT_ANSWER_BEGIN, qctx); + + if (query_checkrrl(qctx, result) != ISC_R_SUCCESS) { + return (ns_query_done(qctx)); + } + + if (!dns_name_equal(qctx->client->query.qname, dns_rootname)) { + result = query_checkrpz(qctx, result); + if (result == ISC_R_NOTFOUND) { + /* + * RPZ not configured for this view. + */ + goto root_key_sentinel; + } + if (RECURSING(qctx->client) && result == DNS_R_DISALLOWED) { + /* + * We are recursing, and thus RPZ processing is not + * allowed at the moment. This could happen on a + * "stale-answer-client-timeout" lookup. In this case, + * bail out and wait for recursion to complete, as we + * we can't perform the RPZ rewrite rules. + */ + return (result); + } + if (result == ISC_R_COMPLETE) { + return (ns_query_done(qctx)); + } + } + +root_key_sentinel: + /* + * If required, handle special "root-key-sentinel-is-ta-<keyid>" and + * "root-key-sentinel-not-ta-<keyid>" labels by returning SERVFAIL. + */ + if (root_key_sentinel_return_servfail(qctx, result)) { + /* + * Don't record this response in the SERVFAIL cache. + */ + qctx->client->attributes |= NS_CLIENTATTR_NOSETFC; + QUERY_ERROR(qctx, DNS_R_SERVFAIL); + return (ns_query_done(qctx)); + } + + switch (result) { + case ISC_R_SUCCESS: + return (query_prepresponse(qctx)); + + case DNS_R_GLUE: + case DNS_R_ZONECUT: + INSIST(qctx->is_zone); + qctx->authoritative = false; + return (query_prepresponse(qctx)); + + case ISC_R_NOTFOUND: + return (query_notfound(qctx)); + + case DNS_R_DELEGATION: + return (query_delegation(qctx)); + + case DNS_R_EMPTYNAME: + case DNS_R_NXRRSET: + return (query_nodata(qctx, result)); + + case DNS_R_EMPTYWILD: + case DNS_R_NXDOMAIN: + return (query_nxdomain(qctx, result)); + + case DNS_R_COVERINGNSEC: + return (query_coveringnsec(qctx)); + + case DNS_R_NCACHENXDOMAIN: + result = query_redirect(qctx); + if (result != ISC_R_COMPLETE) { + return (result); + } + return (query_ncache(qctx, DNS_R_NCACHENXDOMAIN)); + + case DNS_R_NCACHENXRRSET: + return (query_ncache(qctx, DNS_R_NCACHENXRRSET)); + + case DNS_R_CNAME: + return (query_cname(qctx)); + + case DNS_R_DNAME: + return (query_dname(qctx)); + + default: + /* + * Something has gone wrong. + */ + snprintf(errmsg, sizeof(errmsg) - 1, + "query_gotanswer: unexpected error: %s", + isc_result_totext(result)); + CCTRACE(ISC_LOG_ERROR, errmsg); + if (query_usestale(qctx, result)) { + /* + * If serve-stale is enabled, query_usestale() already + * set up 'qctx' for looking up a stale response. + */ + return (query_lookup(qctx)); + } + + /* + * Regardless of the triggering result, we definitely + * want to return SERVFAIL from here. + */ + qctx->client->rcode_override = dns_rcode_servfail; + + QUERY_ERROR(qctx, result); + return (ns_query_done(qctx)); + } + +cleanup: + return (result); +} + +static void +query_addnoqnameproof(query_ctx_t *qctx) { + ns_client_t *client = qctx->client; + isc_buffer_t *dbuf, b; + dns_name_t *fname = NULL; + dns_rdataset_t *neg = NULL, *negsig = NULL; + isc_result_t result = ISC_R_NOMEMORY; + + CTRACE(ISC_LOG_DEBUG(3), "query_addnoqnameproof"); + + if (qctx->noqname == NULL) { + return; + } + + dbuf = ns_client_getnamebuf(client); + if (dbuf == NULL) { + goto cleanup; + } + + fname = ns_client_newname(client, dbuf, &b); + neg = ns_client_newrdataset(client); + negsig = ns_client_newrdataset(client); + if (fname == NULL || neg == NULL || negsig == NULL) { + goto cleanup; + } + + result = dns_rdataset_getnoqname(qctx->noqname, fname, neg, negsig); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + + query_addrrset(qctx, &fname, &neg, &negsig, dbuf, + DNS_SECTION_AUTHORITY); + + if ((qctx->noqname->attributes & DNS_RDATASETATTR_CLOSEST) == 0) { + goto cleanup; + } + + if (fname == NULL) { + dbuf = ns_client_getnamebuf(client); + if (dbuf == NULL) { + goto cleanup; + } + fname = ns_client_newname(client, dbuf, &b); + } + + if (neg == NULL) { + neg = ns_client_newrdataset(client); + } else if (dns_rdataset_isassociated(neg)) { + dns_rdataset_disassociate(neg); + } + + if (negsig == NULL) { + negsig = ns_client_newrdataset(client); + } else if (dns_rdataset_isassociated(negsig)) { + dns_rdataset_disassociate(negsig); + } + + if (fname == NULL || neg == NULL || negsig == NULL) { + goto cleanup; + } + result = dns_rdataset_getclosest(qctx->noqname, fname, neg, negsig); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + + query_addrrset(qctx, &fname, &neg, &negsig, dbuf, + DNS_SECTION_AUTHORITY); + +cleanup: + if (neg != NULL) { + ns_client_putrdataset(client, &neg); + } + if (negsig != NULL) { + ns_client_putrdataset(client, &negsig); + } + if (fname != NULL) { + ns_client_releasename(client, &fname); + } +} + +/*% + * Build the response for a query for type ANY. + */ +static isc_result_t +query_respond_any(query_ctx_t *qctx) { + bool found = false, hidden = false; + dns_rdatasetiter_t *rdsiter = NULL; + isc_result_t result = ISC_R_UNSET; + dns_rdatatype_t onetype = 0; /* type to use for minimal-any */ + isc_buffer_t b; + + CCTRACE(ISC_LOG_DEBUG(3), "query_respond_any"); + + CALL_HOOK(NS_QUERY_RESPOND_ANY_BEGIN, qctx); + + result = dns_db_allrdatasets(qctx->db, qctx->node, qctx->version, 0, 0, + &rdsiter); + if (result != ISC_R_SUCCESS) { + CCTRACE(ISC_LOG_ERROR, "query_respond_any: allrdatasets " + "failed"); + QUERY_ERROR(qctx, result); + return (ns_query_done(qctx)); + } + + /* + * 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 ns_client_keepname() + * now, and pass a NULL dbuf to query_addrrset(). + * + * If we do a query_addrrset() below, we must set qctx->fname to + * NULL before leaving this block, otherwise we might try to + * cleanup qctx->fname even though we're using it! + */ + ns_client_keepname(qctx->client, qctx->fname, qctx->dbuf); + qctx->tname = qctx->fname; + + result = dns_rdatasetiter_first(rdsiter); + while (result == ISC_R_SUCCESS) { + dns_rdatasetiter_current(rdsiter, qctx->rdataset); + + /* + * We found an NS RRset; no need to add one later. + */ + if (qctx->qtype == dns_rdatatype_any && + qctx->rdataset->type == dns_rdatatype_ns) + { + qctx->answer_has_ns = true; + } + + /* + * Note: if we're in this function, then qctx->type + * is guaranteed to be ANY, but qctx->qtype (i.e. the + * original type requested) might have been RRSIG or + * SIG; we need to check for that. + */ + if (qctx->is_zone && qctx->qtype == dns_rdatatype_any && + !dns_db_issecure(qctx->db) && + dns_rdatatype_isdnssec(qctx->rdataset->type)) + { + /* + * The zone may be transitioning from insecure + * to secure. Hide DNSSEC records from ANY queries. + */ + dns_rdataset_disassociate(qctx->rdataset); + hidden = true; + } else if (qctx->view->minimal_any && !TCP(qctx->client) && + !WANTDNSSEC(qctx->client) && + qctx->qtype == dns_rdatatype_any && + (qctx->rdataset->type == dns_rdatatype_sig || + qctx->rdataset->type == dns_rdatatype_rrsig)) + { + CCTRACE(ISC_LOG_DEBUG(5), "query_respond_any: " + "minimal-any skip signature"); + dns_rdataset_disassociate(qctx->rdataset); + } else if (qctx->view->minimal_any && !TCP(qctx->client) && + onetype != 0 && qctx->rdataset->type != onetype && + qctx->rdataset->covers != onetype) + { + CCTRACE(ISC_LOG_DEBUG(5), "query_respond_any: " + "minimal-any skip rdataset"); + dns_rdataset_disassociate(qctx->rdataset); + } else if ((qctx->qtype == dns_rdatatype_any || + qctx->rdataset->type == qctx->qtype) && + qctx->rdataset->type != 0) + { + if (NOQNAME(qctx->rdataset) && WANTDNSSEC(qctx->client)) + { + qctx->noqname = qctx->rdataset; + } else { + qctx->noqname = NULL; + } + + qctx->rpz_st = qctx->client->query.rpz_st; + if (qctx->rpz_st != NULL) { + qctx->rdataset->ttl = + ISC_MIN(qctx->rdataset->ttl, + qctx->rpz_st->m.ttl); + } + + if (!qctx->is_zone && RECURSIONOK(qctx->client)) { + dns_name_t *name; + name = (qctx->fname != NULL) ? qctx->fname + : qctx->tname; + query_prefetch(qctx->client, name, + qctx->rdataset); + } + + /* + * Remember the first RRtype we find so we + * can skip others with minimal-any. + */ + if (qctx->rdataset->type == dns_rdatatype_sig || + qctx->rdataset->type == dns_rdatatype_rrsig) + { + onetype = qctx->rdataset->covers; + } else { + onetype = qctx->rdataset->type; + } + + query_addrrset(qctx, + (qctx->fname != NULL) ? &qctx->fname + : &qctx->tname, + &qctx->rdataset, NULL, NULL, + DNS_SECTION_ANSWER); + + query_addnoqnameproof(qctx); + + found = true; + INSIST(qctx->tname != NULL); + + /* + * rdataset is non-NULL only in certain + * pathological cases involving DNAMEs. + */ + if (qctx->rdataset != NULL) { + ns_client_putrdataset(qctx->client, + &qctx->rdataset); + } + + qctx->rdataset = ns_client_newrdataset(qctx->client); + if (qctx->rdataset == NULL) { + break; + } + } else { + /* + * We're not interested in this rdataset. + */ + dns_rdataset_disassociate(qctx->rdataset); + } + + result = dns_rdatasetiter_next(rdsiter); + } + + dns_rdatasetiter_destroy(&rdsiter); + + if (result != ISC_R_NOMORE) { + CCTRACE(ISC_LOG_ERROR, "query_respond_any: rdataset iterator " + "failed"); + QUERY_ERROR(qctx, DNS_R_SERVFAIL); + return (ns_query_done(qctx)); + } + + if (found) { + /* + * Call hook if any answers were found. + * Do this before releasing qctx->fname, in case + * the hook function needs it. + */ + CALL_HOOK(NS_QUERY_RESPOND_ANY_FOUND, qctx); + } + + if (qctx->fname != NULL) { + dns_message_puttempname(qctx->client->message, &qctx->fname); + } + + if (found) { + /* + * At least one matching rdataset was found + */ + query_addauth(qctx); + } else if (qctx->qtype == dns_rdatatype_rrsig || + qctx->qtype == dns_rdatatype_sig) + { + /* + * No matching rdatasets were found, but we got + * here on a search for RRSIG/SIG, so that's okay. + */ + if (!qctx->is_zone) { + qctx->authoritative = false; + qctx->client->attributes &= ~NS_CLIENTATTR_RA; + query_addauth(qctx); + return (ns_query_done(qctx)); + } + + if (qctx->qtype == dns_rdatatype_rrsig && + dns_db_issecure(qctx->db)) + { + char namebuf[DNS_NAME_FORMATSIZE]; + dns_name_format(qctx->client->query.qname, namebuf, + sizeof(namebuf)); + ns_client_log(qctx->client, DNS_LOGCATEGORY_DNSSEC, + NS_LOGMODULE_QUERY, ISC_LOG_WARNING, + "missing signature for %s", namebuf); + } + + qctx->fname = ns_client_newname(qctx->client, qctx->dbuf, &b); + return (query_sign_nodata(qctx)); + } else if (!hidden) { + /* + * No matching rdatasets were found and nothing was + * deliberately hidden: something must have gone wrong. + */ + QUERY_ERROR(qctx, DNS_R_SERVFAIL); + } + + return (ns_query_done(qctx)); + +cleanup: + return (result); +} + +/* + * Set the expire time, if requested, when answering from a secondary, + * mirror, or primary zone. + */ +static void +query_getexpire(query_ctx_t *qctx) { + dns_zone_t *raw = NULL, *mayberaw; + + CCTRACE(ISC_LOG_DEBUG(3), "query_getexpire"); + + if (qctx->zone == NULL || !qctx->is_zone || + qctx->qtype != dns_rdatatype_soa || + qctx->client->query.restarts != 0 || + (qctx->client->attributes & NS_CLIENTATTR_WANTEXPIRE) == 0) + { + return; + } + + dns_zone_getraw(qctx->zone, &raw); + mayberaw = (raw != NULL) ? raw : qctx->zone; + + if (dns_zone_gettype(mayberaw) == dns_zone_secondary || + dns_zone_gettype(mayberaw) == dns_zone_mirror) + { + isc_time_t expiretime; + uint32_t secs; + dns_zone_getexpiretime(qctx->zone, &expiretime); + secs = isc_time_seconds(&expiretime); + if (secs >= qctx->client->now && qctx->result == ISC_R_SUCCESS) + { + qctx->client->attributes |= NS_CLIENTATTR_HAVEEXPIRE; + qctx->client->expire = secs - qctx->client->now; + } + } else if (dns_zone_gettype(mayberaw) == dns_zone_primary) { + isc_result_t result; + dns_rdata_t rdata = DNS_RDATA_INIT; + dns_rdata_soa_t soa; + + result = dns_rdataset_first(qctx->rdataset); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + + dns_rdataset_current(qctx->rdataset, &rdata); + result = dns_rdata_tostruct(&rdata, &soa, NULL); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + + qctx->client->expire = soa.expire; + qctx->client->attributes |= NS_CLIENTATTR_HAVEEXPIRE; + } + + if (raw != NULL) { + dns_zone_detach(&raw); + } +} + +/*% + * Fill the ANSWER section of a positive response. + */ +static isc_result_t +query_addanswer(query_ctx_t *qctx) { + dns_rdataset_t **sigrdatasetp = NULL; + isc_result_t result = ISC_R_UNSET; + + CCTRACE(ISC_LOG_DEBUG(3), "query_addanswer"); + + CALL_HOOK(NS_QUERY_ADDANSWER_BEGIN, qctx); + + /* + * On normal lookups, clear any rdatasets that were added on a + * lookup due to stale-answer-client-timeout. Do not clear if we + * are going to refresh the RRset, because the stale contents are + * prioritized. + */ + if (QUERY_STALEOK(&qctx->client->query) && + !QUERY_STALETIMEOUT(&qctx->client->query) && !qctx->refresh_rrset) + { + CCTRACE(ISC_LOG_DEBUG(3), "query_clear_stale"); + query_clear_stale(qctx->client); + /* + * We can clear the attribute to prevent redundant clearing + * in subsequent lookups. + */ + qctx->client->query.attributes &= ~NS_QUERYATTR_STALEOK; + } + + if (qctx->dns64) { + result = query_dns64(qctx); + qctx->noqname = NULL; + dns_rdataset_disassociate(qctx->rdataset); + dns_message_puttemprdataset(qctx->client->message, + &qctx->rdataset); + if (result == ISC_R_NOMORE) { +#ifndef dns64_bis_return_excluded_addresses + if (qctx->dns64_exclude) { + if (!qctx->is_zone) { + return (ns_query_done(qctx)); + } + /* + * Add a fake SOA record. + */ + (void)query_addsoa(qctx, 600, + DNS_SECTION_AUTHORITY); + return (ns_query_done(qctx)); + } +#endif /* ifndef dns64_bis_return_excluded_addresses */ + if (qctx->is_zone) { + return (query_nodata(qctx, DNS_R_NXDOMAIN)); + } else { + return (query_ncache(qctx, DNS_R_NXDOMAIN)); + } + } else if (result != ISC_R_SUCCESS) { + qctx->result = result; + return (ns_query_done(qctx)); + } + } else if (qctx->client->query.dns64_aaaaok != NULL) { + query_filter64(qctx); + ns_client_putrdataset(qctx->client, &qctx->rdataset); + } else { + if (!qctx->is_zone && RECURSIONOK(qctx->client) && + !QUERY_STALETIMEOUT(&qctx->client->query)) + { + query_prefetch(qctx->client, qctx->fname, + qctx->rdataset); + } + if (WANTDNSSEC(qctx->client) && qctx->sigrdataset != NULL) { + sigrdatasetp = &qctx->sigrdataset; + } + query_addrrset(qctx, &qctx->fname, &qctx->rdataset, + sigrdatasetp, qctx->dbuf, DNS_SECTION_ANSWER); + } + + return (ISC_R_COMPLETE); + +cleanup: + return (result); +} + +/*% + * Build a response for a "normal" query, for a type other than ANY, + * for which we have an answer (either positive or negative). + */ +static isc_result_t +query_respond(query_ctx_t *qctx) { + isc_result_t result = ISC_R_UNSET; + + CCTRACE(ISC_LOG_DEBUG(3), "query_respond"); + + /* + * Check to see if the AAAA RRset has non-excluded addresses + * in it. If not look for a A RRset. + */ + INSIST(qctx->client->query.dns64_aaaaok == NULL); + + if (qctx->qtype == dns_rdatatype_aaaa && !qctx->dns64_exclude && + !ISC_LIST_EMPTY(qctx->view->dns64) && + qctx->client->message->rdclass == dns_rdataclass_in && + !dns64_aaaaok(qctx->client, qctx->rdataset, qctx->sigrdataset)) + { + /* + * Look to see if there are A records for this name. + */ + qctx->client->query.dns64_ttl = qctx->rdataset->ttl; + SAVE(qctx->client->query.dns64_aaaa, qctx->rdataset); + SAVE(qctx->client->query.dns64_sigaaaa, qctx->sigrdataset); + ns_client_releasename(qctx->client, &qctx->fname); + dns_db_detachnode(qctx->db, &qctx->node); + qctx->type = qctx->qtype = dns_rdatatype_a; + qctx->dns64_exclude = qctx->dns64 = true; + + return (query_lookup(qctx)); + } + + /* + * XXX: This hook is meant to be at the top of this function, + * but is postponed until after DNS64 in order to avoid an + * assertion if the hook causes recursion. (When DNS64 also + * becomes a plugin, it will be necessary to find some + * other way to prevent that assertion, since the order in + * which plugins are configured can't be enforced.) + */ + CALL_HOOK(NS_QUERY_RESPOND_BEGIN, qctx); + + if (NOQNAME(qctx->rdataset) && WANTDNSSEC(qctx->client)) { + qctx->noqname = qctx->rdataset; + } else { + qctx->noqname = NULL; + } + + /* + * Special case NS handling + */ + if (qctx->is_zone && qctx->qtype == dns_rdatatype_ns) { + /* + * We've already got an NS, no need to add one in + * the authority section + */ + if (dns_name_equal(qctx->client->query.qname, + dns_db_origin(qctx->db))) + { + qctx->answer_has_ns = true; + } + + /* + * Always add glue for root priming queries, regardless + * of "minimal-responses" setting. + */ + if (dns_name_equal(qctx->client->query.qname, dns_rootname)) { + qctx->client->query.attributes &= + ~NS_QUERYATTR_NOADDITIONAL; + dns_db_attach(qctx->db, &qctx->client->query.gluedb); + } + } + + /* + * Set expire time + */ + query_getexpire(qctx); + + result = query_addanswer(qctx); + if (result != ISC_R_COMPLETE) { + return (result); + } + + query_addnoqnameproof(qctx); + + /* + * 'qctx->rdataset' will only be non-NULL here if the ANSWER section of + * the message to be sent to the client already contains an RRset with + * the same owner name and the same type as 'qctx->rdataset'. This + * should never happen, with one exception: when chasing DNAME records, + * one of the DNAME records placed in the ANSWER section may turn out + * to be the final answer to the client's query, but we have no way of + * knowing that until now. In such a case, 'qctx->rdataset' will be + * freed later, so we do not need to free it here. + */ + INSIST(qctx->rdataset == NULL || qctx->qtype == dns_rdatatype_dname); + + query_addauth(qctx); + + return (ns_query_done(qctx)); + +cleanup: + return (result); +} + +static isc_result_t +query_dns64(query_ctx_t *qctx) { + ns_client_t *client = qctx->client; + dns_aclenv_t *env = client->manager->aclenv; + dns_name_t *name, *mname; + dns_rdata_t *dns64_rdata; + dns_rdata_t rdata = DNS_RDATA_INIT; + dns_rdatalist_t *dns64_rdatalist; + dns_rdataset_t *dns64_rdataset; + dns_rdataset_t *mrdataset; + isc_buffer_t *buffer; + isc_region_t r; + isc_result_t result; + dns_view_t *view = client->view; + isc_netaddr_t netaddr; + dns_dns64_t *dns64; + unsigned int flags = 0; + const dns_section_t section = DNS_SECTION_ANSWER; + + /*% + * To the current response for 'qctx->client', add the answer RRset + * '*rdatasetp' and an optional signature set '*sigrdatasetp', with + * owner name '*namep', to the answer section, unless they are + * already there. Also add any pertinent additional data. + * + * If 'qctx->dbuf' is not NULL, then 'qctx->fname' is the name + * whose data is stored 'qctx->dbuf'. In this case, + * query_addrrset() guarantees that when it returns the name + * will either have been kept or released. + */ + CTRACE(ISC_LOG_DEBUG(3), "query_dns64"); + + qctx->qtype = qctx->type = dns_rdatatype_aaaa; + + name = qctx->fname; + mname = NULL; + mrdataset = NULL; + buffer = NULL; + dns64_rdata = NULL; + dns64_rdataset = NULL; + dns64_rdatalist = NULL; + result = dns_message_findname( + client->message, section, name, dns_rdatatype_aaaa, + qctx->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(ISC_LOG_DEBUG(3), "query_dns64: dns_message_findname " + "succeeded: done"); + if (qctx->dbuf != NULL) { + ns_client_releasename(client, &qctx->fname); + } + return (ISC_R_SUCCESS); + } else if (result == DNS_R_NXDOMAIN) { + /* + * The name doesn't exist. + */ + if (qctx->dbuf != NULL) { + ns_client_keepname(client, name, qctx->dbuf); + } + dns_message_addname(client->message, name, section); + qctx->fname = NULL; + mname = name; + } else { + RUNTIME_CHECK(result == DNS_R_NXRRSET); + if (qctx->dbuf != NULL) { + ns_client_releasename(client, &qctx->fname); + } + } + + if (qctx->rdataset->trust != dns_trust_secure) { + client->query.attributes &= ~NS_QUERYATTR_SECURE; + } + + isc_netaddr_fromsockaddr(&netaddr, &client->peeraddr); + + isc_buffer_allocate(client->mctx, &buffer, + view->dns64cnt * 16 * + dns_rdataset_count(qctx->rdataset)); + result = dns_message_gettemprdataset(client->message, &dns64_rdataset); + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + result = dns_message_gettemprdatalist(client->message, + &dns64_rdatalist); + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + + dns_rdatalist_init(dns64_rdatalist); + dns64_rdatalist->rdclass = dns_rdataclass_in; + dns64_rdatalist->type = dns_rdatatype_aaaa; + if (client->query.dns64_ttl != UINT32_MAX) { + dns64_rdatalist->ttl = ISC_MIN(qctx->rdataset->ttl, + client->query.dns64_ttl); + } else { + dns64_rdatalist->ttl = ISC_MIN(qctx->rdataset->ttl, 600); + } + + if (RECURSIONOK(client)) { + flags |= DNS_DNS64_RECURSIVE; + } + + /* + * We use the signatures from the A lookup to set DNS_DNS64_DNSSEC + * as this provides a easy way to see if the answer was signed. + */ + if (WANTDNSSEC(qctx->client) && qctx->sigrdataset != NULL && + dns_rdataset_isassociated(qctx->sigrdataset)) + { + flags |= DNS_DNS64_DNSSEC; + } + + for (result = dns_rdataset_first(qctx->rdataset); + result == ISC_R_SUCCESS; + result = dns_rdataset_next(qctx->rdataset)) + { + for (dns64 = ISC_LIST_HEAD(client->view->dns64); dns64 != NULL; + dns64 = dns_dns64_next(dns64)) + { + dns_rdataset_current(qctx->rdataset, &rdata); + isc_buffer_availableregion(buffer, &r); + INSIST(r.length >= 16); + result = dns_dns64_aaaafroma(dns64, &netaddr, + client->signer, env, flags, + rdata.data, r.base); + if (result != ISC_R_SUCCESS) { + dns_rdata_reset(&rdata); + continue; + } + isc_buffer_add(buffer, 16); + isc_buffer_remainingregion(buffer, &r); + isc_buffer_forward(buffer, 16); + result = dns_message_gettemprdata(client->message, + &dns64_rdata); + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + dns_rdata_init(dns64_rdata); + dns_rdata_fromregion(dns64_rdata, dns_rdataclass_in, + dns_rdatatype_aaaa, &r); + ISC_LIST_APPEND(dns64_rdatalist->rdata, dns64_rdata, + link); + dns64_rdata = NULL; + dns_rdata_reset(&rdata); + } + } + if (result != ISC_R_NOMORE) { + goto cleanup; + } + + if (ISC_LIST_EMPTY(dns64_rdatalist->rdata)) { + goto cleanup; + } + + result = dns_rdatalist_tordataset(dns64_rdatalist, dns64_rdataset); + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + dns_rdataset_setownercase(dns64_rdataset, mname); + client->query.attributes |= NS_QUERYATTR_NOADDITIONAL; + dns64_rdataset->trust = qctx->rdataset->trust; + + query_addtoname(mname, dns64_rdataset); + query_setorder(qctx, mname, dns64_rdataset); + + dns64_rdataset = NULL; + dns64_rdatalist = NULL; + dns_message_takebuffer(client->message, &buffer); + inc_stats(client, ns_statscounter_dns64); + result = ISC_R_SUCCESS; + +cleanup: + if (buffer != NULL) { + isc_buffer_free(&buffer); + } + + if (dns64_rdata != NULL) { + dns_message_puttemprdata(client->message, &dns64_rdata); + } + + if (dns64_rdataset != NULL) { + dns_message_puttemprdataset(client->message, &dns64_rdataset); + } + + if (dns64_rdatalist != NULL) { + for (dns64_rdata = ISC_LIST_HEAD(dns64_rdatalist->rdata); + dns64_rdata != NULL; + dns64_rdata = ISC_LIST_HEAD(dns64_rdatalist->rdata)) + { + ISC_LIST_UNLINK(dns64_rdatalist->rdata, dns64_rdata, + link); + dns_message_puttemprdata(client->message, &dns64_rdata); + } + dns_message_puttemprdatalist(client->message, &dns64_rdatalist); + } + + CTRACE(ISC_LOG_DEBUG(3), "query_dns64: done"); + return (result); +} + +static void +query_filter64(query_ctx_t *qctx) { + ns_client_t *client = qctx->client; + dns_name_t *name, *mname; + dns_rdata_t *myrdata; + dns_rdata_t rdata = DNS_RDATA_INIT; + dns_rdatalist_t *myrdatalist; + dns_rdataset_t *myrdataset; + isc_buffer_t *buffer; + isc_region_t r; + isc_result_t result; + unsigned int i; + const dns_section_t section = DNS_SECTION_ANSWER; + + CTRACE(ISC_LOG_DEBUG(3), "query_filter64"); + + INSIST(client->query.dns64_aaaaok != NULL); + INSIST(client->query.dns64_aaaaoklen == + dns_rdataset_count(qctx->rdataset)); + + name = qctx->fname; + mname = NULL; + buffer = NULL; + myrdata = NULL; + myrdataset = NULL; + myrdatalist = NULL; + result = dns_message_findname( + client->message, section, name, dns_rdatatype_aaaa, + qctx->rdataset->covers, &mname, &myrdataset); + if (result == ISC_R_SUCCESS) { + /* + * We've already got an RRset of the given name and type. + * There's nothing else to do; + */ + CTRACE(ISC_LOG_DEBUG(3), "query_filter64: dns_message_findname " + "succeeded: done"); + if (qctx->dbuf != NULL) { + ns_client_releasename(client, &qctx->fname); + } + return; + } else if (result == DNS_R_NXDOMAIN) { + mname = name; + qctx->fname = NULL; + } else { + RUNTIME_CHECK(result == DNS_R_NXRRSET); + if (qctx->dbuf != NULL) { + ns_client_releasename(client, &qctx->fname); + } + qctx->dbuf = NULL; + } + + if (qctx->rdataset->trust != dns_trust_secure) { + client->query.attributes &= ~NS_QUERYATTR_SECURE; + } + + isc_buffer_allocate(client->mctx, &buffer, + 16 * dns_rdataset_count(qctx->rdataset)); + result = dns_message_gettemprdataset(client->message, &myrdataset); + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + result = dns_message_gettemprdatalist(client->message, &myrdatalist); + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + + dns_rdatalist_init(myrdatalist); + myrdatalist->rdclass = dns_rdataclass_in; + myrdatalist->type = dns_rdatatype_aaaa; + myrdatalist->ttl = qctx->rdataset->ttl; + + i = 0; + for (result = dns_rdataset_first(qctx->rdataset); + result == ISC_R_SUCCESS; + result = dns_rdataset_next(qctx->rdataset)) + { + if (!client->query.dns64_aaaaok[i++]) { + continue; + } + dns_rdataset_current(qctx->rdataset, &rdata); + INSIST(rdata.length == 16); + isc_buffer_putmem(buffer, rdata.data, rdata.length); + isc_buffer_remainingregion(buffer, &r); + isc_buffer_forward(buffer, rdata.length); + result = dns_message_gettemprdata(client->message, &myrdata); + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + dns_rdata_init(myrdata); + dns_rdata_fromregion(myrdata, dns_rdataclass_in, + dns_rdatatype_aaaa, &r); + ISC_LIST_APPEND(myrdatalist->rdata, myrdata, link); + myrdata = NULL; + dns_rdata_reset(&rdata); + } + if (result != ISC_R_NOMORE) { + goto cleanup; + } + + result = dns_rdatalist_tordataset(myrdatalist, myrdataset); + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + dns_rdataset_setownercase(myrdataset, name); + client->query.attributes |= NS_QUERYATTR_NOADDITIONAL; + if (mname == name) { + if (qctx->dbuf != NULL) { + ns_client_keepname(client, name, qctx->dbuf); + } + dns_message_addname(client->message, name, section); + qctx->dbuf = NULL; + } + myrdataset->trust = qctx->rdataset->trust; + + query_addtoname(mname, myrdataset); + query_setorder(qctx, mname, myrdataset); + + myrdataset = NULL; + myrdatalist = NULL; + dns_message_takebuffer(client->message, &buffer); + +cleanup: + if (buffer != NULL) { + isc_buffer_free(&buffer); + } + + if (myrdata != NULL) { + dns_message_puttemprdata(client->message, &myrdata); + } + + if (myrdataset != NULL) { + dns_message_puttemprdataset(client->message, &myrdataset); + } + + if (myrdatalist != NULL) { + for (myrdata = ISC_LIST_HEAD(myrdatalist->rdata); + myrdata != NULL; + myrdata = ISC_LIST_HEAD(myrdatalist->rdata)) + { + ISC_LIST_UNLINK(myrdatalist->rdata, myrdata, link); + dns_message_puttemprdata(client->message, &myrdata); + } + dns_message_puttemprdatalist(client->message, &myrdatalist); + } + if (qctx->dbuf != NULL) { + ns_client_releasename(client, &name); + } + + CTRACE(ISC_LOG_DEBUG(3), "query_filter64: done"); +} + +/*% + * Handle the case of a name not being found in a database lookup. + * Called from query_gotanswer(). Passes off processing to + * query_delegation() for a root referral if appropriate. + */ +static isc_result_t +query_notfound(query_ctx_t *qctx) { + isc_result_t result = ISC_R_UNSET; + + CCTRACE(ISC_LOG_DEBUG(3), "query_notfound"); + + CALL_HOOK(NS_QUERY_NOTFOUND_BEGIN, qctx); + + INSIST(!qctx->is_zone); + + if (qctx->db != NULL) { + dns_db_detach(&qctx->db); + } + + /* + * If the cache doesn't even have the root NS, + * try to get that from the hints DB. + */ + if (qctx->view->hints != NULL) { + dns_clientinfomethods_t cm; + dns_clientinfo_t ci; + + dns_clientinfomethods_init(&cm, ns_client_sourceip); + dns_clientinfo_init(&ci, qctx->client, NULL); + + dns_db_attach(qctx->view->hints, &qctx->db); + result = dns_db_findext(qctx->db, dns_rootname, NULL, + dns_rdatatype_ns, 0, qctx->client->now, + &qctx->node, qctx->fname, &cm, &ci, + qctx->rdataset, qctx->sigrdataset); + } else { + /* We have no hints. */ + result = ISC_R_FAILURE; + } + if (result != ISC_R_SUCCESS) { + /* + * Nonsensical root hints may require cleanup. + */ + qctx_clean(qctx); + + /* + * We don't have any root server hints, but + * we may have working forwarders, so try to + * recurse anyway. + */ + if (RECURSIONOK(qctx->client)) { + INSIST(!REDIRECT(qctx->client)); + result = ns_query_recurse(qctx->client, qctx->qtype, + qctx->client->query.qname, + NULL, NULL, qctx->resuming); + if (result == ISC_R_SUCCESS) { + CALL_HOOK(NS_QUERY_NOTFOUND_RECURSE, qctx); + qctx->client->query.attributes |= + NS_QUERYATTR_RECURSING; + + if (qctx->dns64) { + qctx->client->query.attributes |= + NS_QUERYATTR_DNS64; + } + if (qctx->dns64_exclude) { + qctx->client->query.attributes |= + NS_QUERYATTR_DNS64EXCLUDE; + } + } else if (query_usestale(qctx, result)) { + /* + * If serve-stale is enabled, query_usestale() + * already set up 'qctx' for looking up a + * stale response. + */ + return (query_lookup(qctx)); + } else { + QUERY_ERROR(qctx, result); + } + return (ns_query_done(qctx)); + } else { + /* Unable to give root server referral. */ + CCTRACE(ISC_LOG_ERROR, "unable to give root server " + "referral"); + QUERY_ERROR(qctx, result); + return (ns_query_done(qctx)); + } + } + + return (query_delegation(qctx)); + +cleanup: + return (result); +} + +/*% + * We have a delegation but recursion is not allowed, so return the delegation + * to the client. + */ +static isc_result_t +query_prepare_delegation_response(query_ctx_t *qctx) { + isc_result_t result = ISC_R_UNSET; + dns_rdataset_t **sigrdatasetp = NULL; + bool detach = false; + + CALL_HOOK(NS_QUERY_PREP_DELEGATION_BEGIN, qctx); + + /* + * qctx->fname could be released in query_addrrset(), so save a copy of + * it here in case we need it. + */ + dns_fixedname_init(&qctx->dsname); + dns_name_copy(qctx->fname, dns_fixedname_name(&qctx->dsname)); + + /* + * This is the best answer. + */ + qctx->client->query.isreferral = true; + + if (!dns_db_iscache(qctx->db) && qctx->client->query.gluedb == NULL) { + dns_db_attach(qctx->db, &qctx->client->query.gluedb); + detach = true; + } + + /* + * We must ensure NOADDITIONAL is off, because the generation of + * additional data is required in delegations. + */ + qctx->client->query.attributes &= ~NS_QUERYATTR_NOADDITIONAL; + if (WANTDNSSEC(qctx->client) && qctx->sigrdataset != NULL) { + sigrdatasetp = &qctx->sigrdataset; + } + query_addrrset(qctx, &qctx->fname, &qctx->rdataset, sigrdatasetp, + qctx->dbuf, DNS_SECTION_AUTHORITY); + if (detach) { + dns_db_detach(&qctx->client->query.gluedb); + } + + /* + * Add DS/NSEC(3) record(s) if needed. + */ + query_addds(qctx); + + return (ns_query_done(qctx)); + +cleanup: + return (result); +} + +/*% + * Handle a delegation response from an authoritative lookup. This + * may trigger additional lookups, e.g. from the cache database to + * see if we have a better answer; if that is not allowed, return the + * delegation to the client and call ns_query_done(). + */ +static isc_result_t +query_zone_delegation(query_ctx_t *qctx) { + isc_result_t result = ISC_R_UNSET; + + CALL_HOOK(NS_QUERY_ZONE_DELEGATION_BEGIN, qctx); + + /* + * If the query type is DS, look to see if we are + * authoritative for the child zone + */ + if (!RECURSIONOK(qctx->client) && + (qctx->options & DNS_GETDB_NOEXACT) != 0 && + qctx->qtype == dns_rdatatype_ds) + { + dns_db_t *tdb = NULL; + dns_zone_t *tzone = NULL; + dns_dbversion_t *tversion = NULL; + result = query_getzonedb( + qctx->client, qctx->client->query.qname, qctx->qtype, + DNS_GETDB_PARTIAL, &tzone, &tdb, &tversion); + if (result != ISC_R_SUCCESS) { + if (tdb != NULL) { + dns_db_detach(&tdb); + } + if (tzone != NULL) { + dns_zone_detach(&tzone); + } + } else { + qctx->options &= ~DNS_GETDB_NOEXACT; + ns_client_putrdataset(qctx->client, &qctx->rdataset); + if (qctx->sigrdataset != NULL) { + ns_client_putrdataset(qctx->client, + &qctx->sigrdataset); + } + if (qctx->fname != NULL) { + ns_client_releasename(qctx->client, + &qctx->fname); + } + if (qctx->node != NULL) { + dns_db_detachnode(qctx->db, &qctx->node); + } + if (qctx->db != NULL) { + dns_db_detach(&qctx->db); + } + if (qctx->zone != NULL) { + dns_zone_detach(&qctx->zone); + } + qctx->version = NULL; + RESTORE(qctx->version, tversion); + RESTORE(qctx->db, tdb); + RESTORE(qctx->zone, tzone); + qctx->authoritative = true; + + return (query_lookup(qctx)); + } + } + + if (USECACHE(qctx->client) && + (RECURSIONOK(qctx->client) || + (qctx->zone != NULL && + dns_zone_gettype(qctx->zone) == dns_zone_mirror))) + { + /* + * 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. If not, then query_lookup() calls + * query_notfound() which calls query_delegation(), and + * we'll restore these values there. + */ + ns_client_keepname(qctx->client, qctx->fname, qctx->dbuf); + SAVE(qctx->zdb, qctx->db); + SAVE(qctx->znode, qctx->node); + SAVE(qctx->zfname, qctx->fname); + SAVE(qctx->zversion, qctx->version); + SAVE(qctx->zrdataset, qctx->rdataset); + SAVE(qctx->zsigrdataset, qctx->sigrdataset); + dns_db_attach(qctx->view->cachedb, &qctx->db); + qctx->is_zone = false; + + return (query_lookup(qctx)); + } + + return (query_prepare_delegation_response(qctx)); + +cleanup: + return (result); +} + +/*% + * Handle delegation responses, including root referrals. + * + * If the delegation was returned from authoritative data, + * call query_zone_delgation(). Otherwise, we can start + * recursion if allowed; or else return the delegation to the + * client and call ns_query_done(). + */ +static isc_result_t +query_delegation(query_ctx_t *qctx) { + isc_result_t result = ISC_R_UNSET; + + CCTRACE(ISC_LOG_DEBUG(3), "query_delegation"); + + CALL_HOOK(NS_QUERY_DELEGATION_BEGIN, qctx); + + qctx->authoritative = false; + + if (qctx->is_zone) { + return (query_zone_delegation(qctx)); + } + + if (qctx->zfname != NULL && + (!dns_name_issubdomain(qctx->fname, qctx->zfname) || + (qctx->is_staticstub_zone && + dns_name_equal(qctx->fname, qctx->zfname)))) + { + /* + * In the following cases use "authoritative" + * data instead of the cache delegation: + * 1. We've already got a delegation from + * authoritative data, and it is better + * than what we found in the cache. + * (See the comment above.) + * 2. The query name matches the origin name + * of a static-stub zone. This needs to be + * considered for the case where the NS of + * the static-stub zone and the cached NS + * are different. We still need to contact + * the nameservers configured in the + * static-stub zone. + */ + ns_client_releasename(qctx->client, &qctx->fname); + + /* + * We've already done ns_client_keepname() on + * qctx->zfname, so we must set dbuf to NULL to + * prevent query_addrrset() from trying to + * call ns_client_keepname() again. + */ + qctx->dbuf = NULL; + ns_client_putrdataset(qctx->client, &qctx->rdataset); + if (qctx->sigrdataset != NULL) { + ns_client_putrdataset(qctx->client, &qctx->sigrdataset); + } + qctx->version = NULL; + + dns_db_detachnode(qctx->db, &qctx->node); + dns_db_detach(&qctx->db); + RESTORE(qctx->db, qctx->zdb); + RESTORE(qctx->node, qctx->znode); + RESTORE(qctx->fname, qctx->zfname); + RESTORE(qctx->version, qctx->zversion); + RESTORE(qctx->rdataset, qctx->zrdataset); + RESTORE(qctx->sigrdataset, qctx->zsigrdataset); + } + + result = query_delegation_recurse(qctx); + if (result != ISC_R_COMPLETE) { + return (result); + } + + return (query_prepare_delegation_response(qctx)); + +cleanup: + return (result); +} + +/*% + * Handle recursive queries that are triggered as part of the + * delegation process. + */ +static isc_result_t +query_delegation_recurse(query_ctx_t *qctx) { + isc_result_t result = ISC_R_UNSET; + dns_name_t *qname = qctx->client->query.qname; + + CCTRACE(ISC_LOG_DEBUG(3), "query_delegation_recurse"); + + if (!RECURSIONOK(qctx->client)) { + return (ISC_R_COMPLETE); + } + + CALL_HOOK(NS_QUERY_DELEGATION_RECURSE_BEGIN, qctx); + + /* + * We have a delegation and recursion is allowed, + * so we call ns_query_recurse() to follow it. + * This phase of the query processing is done; + * we'll resume via fetch_callback() and + * query_resume() when the recursion is complete. + */ + + INSIST(!REDIRECT(qctx->client)); + + if (dns_rdatatype_atparent(qctx->type)) { + /* + * Parent is authoritative for this RDATA type (i.e. DS). + */ + result = ns_query_recurse(qctx->client, qctx->qtype, qname, + NULL, NULL, qctx->resuming); + } else if (qctx->dns64) { + /* + * Look up an A record so we can synthesize DNS64. + */ + result = ns_query_recurse(qctx->client, dns_rdatatype_a, qname, + NULL, NULL, qctx->resuming); + } else { + /* + * Any other recursion. + */ + result = ns_query_recurse(qctx->client, qctx->qtype, qname, + qctx->fname, qctx->rdataset, + qctx->resuming); + } + + if (result == ISC_R_SUCCESS) { + qctx->client->query.attributes |= NS_QUERYATTR_RECURSING; + if (qctx->dns64) { + qctx->client->query.attributes |= NS_QUERYATTR_DNS64; + } + if (qctx->dns64_exclude) { + qctx->client->query.attributes |= + NS_QUERYATTR_DNS64EXCLUDE; + } + } else if (query_usestale(qctx, result)) { + /* + * If serve-stale is enabled, query_usestale() already set up + * 'qctx' for looking up a stale response. + */ + return (query_lookup(qctx)); + } else { + QUERY_ERROR(qctx, result); + } + + return (ns_query_done(qctx)); + +cleanup: + return (result); +} + +/*% + * Add DS/NSEC(3) record(s) if needed. + */ +static void +query_addds(query_ctx_t *qctx) { + ns_client_t *client = qctx->client; + dns_fixedname_t fixed; + dns_name_t *fname = NULL; + dns_name_t *rname = NULL; + dns_name_t *name; + dns_rdataset_t *rdataset = NULL, *sigrdataset = NULL; + isc_buffer_t *dbuf, b; + isc_result_t result; + unsigned int count; + + CTRACE(ISC_LOG_DEBUG(3), "query_addds"); + + /* + * DS not needed. + */ + if (!WANTDNSSEC(client)) { + return; + } + + /* + * We'll need some resources... + */ + rdataset = ns_client_newrdataset(client); + sigrdataset = ns_client_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(qctx->db, qctx->node, qctx->version, + 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( + qctx->db, qctx->node, qctx->version, dns_rdatatype_nsec, + 0, client->now, rdataset, sigrdataset); + } + if (result != ISC_R_SUCCESS && result != ISC_R_NOTFOUND) { + goto addnsec3; + } + if (!dns_rdataset_isassociated(rdataset) || + !dns_rdataset_isassociated(sigrdataset)) + { + goto addnsec3; + } + + /* + * We've already added the NS record, so if the name's not there, + * we have other problems. + */ + result = dns_message_firstname(client->message, DNS_SECTION_AUTHORITY); + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + + /* + * Find the delegation in the response message - it is not necessarily + * the first name in the AUTHORITY section when wildcard processing is + * involved. + */ + while (result == ISC_R_SUCCESS) { + 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) { + break; + } + result = dns_message_nextname(client->message, + DNS_SECTION_AUTHORITY); + } + + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + + /* + * Add the relevant RRset (DS or NSEC) to the delegation. + */ + query_addrrset(qctx, &rname, &rdataset, &sigrdataset, NULL, + DNS_SECTION_AUTHORITY); + goto cleanup; + +addnsec3: + if (!dns_db_iszone(qctx->db)) { + goto cleanup; + } + /* + * Add the NSEC3 which proves the DS does not exist. + */ + dbuf = ns_client_getnamebuf(client); + if (dbuf == NULL) { + goto cleanup; + } + fname = ns_client_newname(client, dbuf, &b); + dns_fixedname_init(&fixed); + if (dns_rdataset_isassociated(rdataset)) { + dns_rdataset_disassociate(rdataset); + } + if (dns_rdataset_isassociated(sigrdataset)) { + dns_rdataset_disassociate(sigrdataset); + } + name = dns_fixedname_name(&qctx->dsname); + query_findclosestnsec3(name, qctx->db, qctx->version, client, rdataset, + sigrdataset, fname, true, + dns_fixedname_name(&fixed)); + if (!dns_rdataset_isassociated(rdataset)) { + goto cleanup; + } + query_addrrset(qctx, &fname, &rdataset, &sigrdataset, dbuf, + DNS_SECTION_AUTHORITY); + /* + * Did we find the closest provable encloser instead? + * If so add the nearest to the closest provable encloser. + */ + if (!dns_name_equal(name, dns_fixedname_name(&fixed))) { + count = dns_name_countlabels(dns_fixedname_name(&fixed)) + 1; + dns_name_getlabelsequence(name, + dns_name_countlabels(name) - count, + count, dns_fixedname_name(&fixed)); + fixfname(client, &fname, &dbuf, &b); + fixrdataset(client, &rdataset); + fixrdataset(client, &sigrdataset); + if (fname == NULL || rdataset == NULL || sigrdataset == NULL) { + goto cleanup; + } + query_findclosestnsec3(dns_fixedname_name(&fixed), qctx->db, + qctx->version, client, rdataset, + sigrdataset, fname, false, NULL); + if (!dns_rdataset_isassociated(rdataset)) { + goto cleanup; + } + query_addrrset(qctx, &fname, &rdataset, &sigrdataset, dbuf, + DNS_SECTION_AUTHORITY); + } + +cleanup: + if (rdataset != NULL) { + ns_client_putrdataset(client, &rdataset); + } + if (sigrdataset != NULL) { + ns_client_putrdataset(client, &sigrdataset); + } + if (fname != NULL) { + ns_client_releasename(client, &fname); + } +} + +/*% + * Handle authoritative NOERROR/NODATA responses. + */ +static isc_result_t +query_nodata(query_ctx_t *qctx, isc_result_t res) { + isc_result_t result = res; + + CCTRACE(ISC_LOG_DEBUG(3), "query_nodata"); + + CALL_HOOK(NS_QUERY_NODATA_BEGIN, qctx); + +#ifdef dns64_bis_return_excluded_addresses + if (qctx->dns64) +#else /* ifdef dns64_bis_return_excluded_addresses */ + if (qctx->dns64 && !qctx->dns64_exclude) +#endif /* ifdef dns64_bis_return_excluded_addresses */ + { + isc_buffer_t b; + /* + * Restore the answers from the previous AAAA lookup. + */ + if (qctx->rdataset != NULL) { + ns_client_putrdataset(qctx->client, &qctx->rdataset); + } + if (qctx->sigrdataset != NULL) { + ns_client_putrdataset(qctx->client, &qctx->sigrdataset); + } + RESTORE(qctx->rdataset, qctx->client->query.dns64_aaaa); + RESTORE(qctx->sigrdataset, qctx->client->query.dns64_sigaaaa); + if (qctx->fname == NULL) { + qctx->dbuf = ns_client_getnamebuf(qctx->client); + if (qctx->dbuf == NULL) { + CCTRACE(ISC_LOG_ERROR, "query_nodata: " + "ns_client_getnamebuf " + "failed (3)"); + QUERY_ERROR(qctx, ISC_R_NOMEMORY); + return (ns_query_done(qctx)); + } + qctx->fname = ns_client_newname(qctx->client, + qctx->dbuf, &b); + if (qctx->fname == NULL) { + CCTRACE(ISC_LOG_ERROR, "query_nodata: " + "ns_client_newname " + "failed (3)"); + QUERY_ERROR(qctx, ISC_R_NOMEMORY); + return (ns_query_done(qctx)); + } + } + dns_name_copy(qctx->client->query.qname, qctx->fname); + qctx->dns64 = false; +#ifdef dns64_bis_return_excluded_addresses + /* + * Resume the diverted processing of the AAAA response? + */ + if (qctx->dns64_exclude) { + return (query_prepresponse(qctx)); + } +#endif /* ifdef dns64_bis_return_excluded_addresses */ + } else if ((result == DNS_R_NXRRSET || result == DNS_R_NCACHENXRRSET) && + !ISC_LIST_EMPTY(qctx->view->dns64) && !qctx->nxrewrite && + qctx->client->message->rdclass == dns_rdataclass_in && + qctx->qtype == dns_rdatatype_aaaa) + { + /* + * Look to see if there are A records for this name. + */ + switch (result) { + case DNS_R_NCACHENXRRSET: + /* + * This is from the negative cache; if the ttl is + * zero, we need to work out whether we have just + * decremented to zero or there was no negative + * cache ttl in the answer. + */ + if (qctx->rdataset->ttl != 0) { + qctx->client->query.dns64_ttl = + qctx->rdataset->ttl; + break; + } + if (dns_rdataset_first(qctx->rdataset) == ISC_R_SUCCESS) + { + qctx->client->query.dns64_ttl = 0; + } + break; + case DNS_R_NXRRSET: + qctx->client->query.dns64_ttl = + dns64_ttl(qctx->db, qctx->version); + break; + default: + UNREACHABLE(); + } + + SAVE(qctx->client->query.dns64_aaaa, qctx->rdataset); + SAVE(qctx->client->query.dns64_sigaaaa, qctx->sigrdataset); + ns_client_releasename(qctx->client, &qctx->fname); + dns_db_detachnode(qctx->db, &qctx->node); + qctx->type = qctx->qtype = dns_rdatatype_a; + qctx->dns64 = true; + return (query_lookup(qctx)); + } + + if (qctx->is_zone) { + return (query_sign_nodata(qctx)); + } else { + /* + * We don't call query_addrrset() because we don't need any + * of its extra features (and things would probably break!). + */ + if (dns_rdataset_isassociated(qctx->rdataset)) { + ns_client_keepname(qctx->client, qctx->fname, + qctx->dbuf); + dns_message_addname(qctx->client->message, qctx->fname, + DNS_SECTION_AUTHORITY); + ISC_LIST_APPEND(qctx->fname->list, qctx->rdataset, + link); + qctx->fname = NULL; + qctx->rdataset = NULL; + } + } + + return (ns_query_done(qctx)); + +cleanup: + return (result); +} + +/*% + * Add RRSIGs for NOERROR/NODATA responses when answering authoritatively. + */ +isc_result_t +query_sign_nodata(query_ctx_t *qctx) { + isc_result_t result; + + CCTRACE(ISC_LOG_DEBUG(3), "query_sign_nodata"); + + /* + * Look for a NSEC3 record if we don't have a NSEC record. + */ + if (qctx->redirected) { + return (ns_query_done(qctx)); + } + if (!dns_rdataset_isassociated(qctx->rdataset) && + WANTDNSSEC(qctx->client)) + { + if ((qctx->fname->attributes & DNS_NAMEATTR_WILDCARD) == 0) { + dns_name_t *found; + dns_name_t *qname; + dns_fixedname_t fixed; + isc_buffer_t b; + + found = dns_fixedname_initname(&fixed); + qname = qctx->client->query.qname; + + query_findclosestnsec3(qname, qctx->db, qctx->version, + qctx->client, qctx->rdataset, + qctx->sigrdataset, qctx->fname, + true, found); + /* + * Did we find the closest provable encloser + * instead? If so add the nearest to the + * closest provable encloser. + */ + if (dns_rdataset_isassociated(qctx->rdataset) && + !dns_name_equal(qname, found) && + (((qctx->client->sctx->options & + NS_SERVER_NONEAREST) == 0) || + qctx->qtype == dns_rdatatype_ds)) + { + unsigned int count; + unsigned int skip; + + /* + * Add the closest provable encloser. + */ + query_addrrset(qctx, &qctx->fname, + &qctx->rdataset, + &qctx->sigrdataset, qctx->dbuf, + DNS_SECTION_AUTHORITY); + + count = dns_name_countlabels(found) + 1; + skip = dns_name_countlabels(qname) - count; + dns_name_getlabelsequence(qname, skip, count, + found); + + fixfname(qctx->client, &qctx->fname, + &qctx->dbuf, &b); + fixrdataset(qctx->client, &qctx->rdataset); + fixrdataset(qctx->client, &qctx->sigrdataset); + if (qctx->fname == NULL || + qctx->rdataset == NULL || + qctx->sigrdataset == NULL) + { + CCTRACE(ISC_LOG_ERROR, "query_sign_" + "nodata: " + "failure " + "getting " + "closest " + "encloser"); + QUERY_ERROR(qctx, ISC_R_NOMEMORY); + return (ns_query_done(qctx)); + } + /* + * 'nearest' doesn't exist so + * 'exist' is set to false. + */ + query_findclosestnsec3( + found, qctx->db, qctx->version, + qctx->client, qctx->rdataset, + qctx->sigrdataset, qctx->fname, false, + NULL); + } + } else { + ns_client_releasename(qctx->client, &qctx->fname); + query_addwildcardproof(qctx, false, true); + } + } + if (dns_rdataset_isassociated(qctx->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. + */ + ns_client_keepname(qctx->client, qctx->fname, qctx->dbuf); + } else if (qctx->fname != NULL) { + /* + * We're not going to use fname, and need to release + * our hold on the name buffer so query_addsoa() + * may use it. + */ + ns_client_releasename(qctx->client, &qctx->fname); + } + + /* + * The RPZ SOA has already been added to the additional section + * if this was an RPZ rewrite, but if it wasn't, add it now. + */ + if (!qctx->nxrewrite) { + result = query_addsoa(qctx, UINT32_MAX, DNS_SECTION_AUTHORITY); + if (result != ISC_R_SUCCESS) { + QUERY_ERROR(qctx, result); + return (ns_query_done(qctx)); + } + } + + /* + * Add NSEC record if we found one. + */ + if (WANTDNSSEC(qctx->client) && + dns_rdataset_isassociated(qctx->rdataset)) + { + query_addnxrrsetnsec(qctx); + } + + return (ns_query_done(qctx)); +} + +static void +query_addnxrrsetnsec(query_ctx_t *qctx) { + ns_client_t *client = qctx->client; + 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; + + INSIST(qctx->fname != NULL); + + if ((qctx->fname->attributes & DNS_NAMEATTR_WILDCARD) == 0) { + query_addrrset(qctx, &qctx->fname, &qctx->rdataset, + &qctx->sigrdataset, NULL, DNS_SECTION_AUTHORITY); + return; + } + + if (qctx->sigrdataset == NULL || + !dns_rdataset_isassociated(qctx->sigrdataset)) + { + return; + } + + if (dns_rdataset_first(qctx->sigrdataset) != ISC_R_SUCCESS) { + return; + } + + dns_rdata_init(&sigrdata); + dns_rdataset_current(qctx->sigrdataset, &sigrdata); + result = dns_rdata_tostruct(&sigrdata, &sig, NULL); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + + labels = dns_name_countlabels(qctx->fname); + if ((unsigned int)sig.labels + 1 >= labels) { + return; + } + + query_addwildcardproof(qctx, true, false); + + /* + * We'll need some resources... + */ + dbuf = ns_client_getnamebuf(client); + if (dbuf == NULL) { + return; + } + + fname = ns_client_newname(client, dbuf, &b); + if (fname == NULL) { + return; + } + + dns_name_split(qctx->fname, 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(qctx, &fname, &qctx->rdataset, &qctx->sigrdataset, dbuf, + DNS_SECTION_AUTHORITY); +} + +/*% + * Handle NXDOMAIN and empty wildcard responses. + */ +static isc_result_t +query_nxdomain(query_ctx_t *qctx, isc_result_t res) { + dns_section_t section; + uint32_t ttl; + isc_result_t result = res; + bool empty_wild = (res == DNS_R_EMPTYWILD); + + CCTRACE(ISC_LOG_DEBUG(3), "query_nxdomain"); + + CALL_HOOK(NS_QUERY_NXDOMAIN_BEGIN, qctx); + + INSIST(qctx->is_zone || REDIRECT(qctx->client)); + + if (!empty_wild) { + result = query_redirect(qctx); + if (result != ISC_R_COMPLETE) { + return (result); + } + } + + if (dns_rdataset_isassociated(qctx->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. + */ + ns_client_keepname(qctx->client, qctx->fname, qctx->dbuf); + } else if (qctx->fname != NULL) { + /* + * We're not going to use fname, and need to release + * our hold on the name buffer so query_addsoa() + * may use it. + */ + ns_client_releasename(qctx->client, &qctx->fname); + } + + /* + * Add SOA to the additional section if generated by a + * RPZ rewrite. + * + * 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. + */ + section = qctx->nxrewrite ? DNS_SECTION_ADDITIONAL + : DNS_SECTION_AUTHORITY; + ttl = UINT32_MAX; + if (!qctx->nxrewrite && qctx->qtype == dns_rdatatype_soa && + qctx->zone != NULL && dns_zone_getzeronosoattl(qctx->zone)) + { + ttl = 0; + } + if (!qctx->nxrewrite || + (qctx->rpz_st != NULL && qctx->rpz_st->m.rpz->addsoa)) + { + result = query_addsoa(qctx, ttl, section); + if (result != ISC_R_SUCCESS) { + QUERY_ERROR(qctx, result); + return (ns_query_done(qctx)); + } + } + + if (WANTDNSSEC(qctx->client)) { + /* + * Add NSEC record if we found one. + */ + if (dns_rdataset_isassociated(qctx->rdataset)) { + query_addrrset(qctx, &qctx->fname, &qctx->rdataset, + &qctx->sigrdataset, NULL, + DNS_SECTION_AUTHORITY); + } + query_addwildcardproof(qctx, false, false); + } + + /* + * Set message rcode. + */ + if (empty_wild) { + qctx->client->message->rcode = dns_rcode_noerror; + } else { + qctx->client->message->rcode = dns_rcode_nxdomain; + } + + return (ns_query_done(qctx)); + +cleanup: + return (result); +} + +/* + * Handle both types of NXDOMAIN redirection, calling redirect() + * (which implements type redirect zones) and redirect2() (which + * implements recursive nxdomain-redirect lookups). + * + * Any result code other than ISC_R_COMPLETE means redirection was + * successful and the result code should be returned up the call stack. + * + * ISC_R_COMPLETE means we reached the end of this function without + * redirecting, so query processing should continue past it. + */ +static isc_result_t +query_redirect(query_ctx_t *qctx) { + isc_result_t result; + + CCTRACE(ISC_LOG_DEBUG(3), "query_redirect"); + + result = redirect(qctx->client, qctx->fname, qctx->rdataset, + &qctx->node, &qctx->db, &qctx->version, qctx->type); + switch (result) { + case ISC_R_SUCCESS: + inc_stats(qctx->client, ns_statscounter_nxdomainredirect); + return (query_prepresponse(qctx)); + case DNS_R_NXRRSET: + qctx->redirected = true; + qctx->is_zone = true; + return (query_nodata(qctx, DNS_R_NXRRSET)); + case DNS_R_NCACHENXRRSET: + qctx->redirected = true; + qctx->is_zone = false; + return (query_ncache(qctx, DNS_R_NCACHENXRRSET)); + default: + break; + } + + result = redirect2(qctx->client, qctx->fname, qctx->rdataset, + &qctx->node, &qctx->db, &qctx->version, qctx->type, + &qctx->is_zone); + switch (result) { + case ISC_R_SUCCESS: + inc_stats(qctx->client, ns_statscounter_nxdomainredirect); + return (query_prepresponse(qctx)); + case DNS_R_CONTINUE: + inc_stats(qctx->client, + ns_statscounter_nxdomainredirect_rlookup); + SAVE(qctx->client->query.redirect.db, qctx->db); + SAVE(qctx->client->query.redirect.node, qctx->node); + SAVE(qctx->client->query.redirect.zone, qctx->zone); + qctx->client->query.redirect.qtype = qctx->qtype; + INSIST(qctx->rdataset != NULL); + SAVE(qctx->client->query.redirect.rdataset, qctx->rdataset); + SAVE(qctx->client->query.redirect.sigrdataset, + qctx->sigrdataset); + qctx->client->query.redirect.result = DNS_R_NCACHENXDOMAIN; + dns_name_copy(qctx->fname, qctx->client->query.redirect.fname); + qctx->client->query.redirect.authoritative = + qctx->authoritative; + qctx->client->query.redirect.is_zone = qctx->is_zone; + return (ns_query_done(qctx)); + case DNS_R_NXRRSET: + qctx->redirected = true; + qctx->is_zone = true; + return (query_nodata(qctx, DNS_R_NXRRSET)); + case DNS_R_NCACHENXRRSET: + qctx->redirected = true; + qctx->is_zone = false; + return (query_ncache(qctx, DNS_R_NCACHENXRRSET)); + default: + break; + } + + return (ISC_R_COMPLETE); +} + +/*% + * Logging function to be passed to dns_nsec_noexistnodata. + */ +static void +log_noexistnodata(void *val, int level, const char *fmt, ...) { + query_ctx_t *qctx = val; + va_list ap; + + va_start(ap, fmt); + ns_client_logv(qctx->client, NS_LOGCATEGORY_QUERIES, NS_LOGMODULE_QUERY, + level, fmt, ap); + va_end(ap); +} + +static dns_ttl_t +query_synthttl(dns_rdataset_t *soardataset, dns_rdataset_t *sigsoardataset, + dns_rdataset_t *p1rdataset, dns_rdataset_t *sigp1rdataset, + dns_rdataset_t *p2rdataset, dns_rdataset_t *sigp2rdataset) { + dns_rdata_soa_t soa; + dns_rdata_t rdata = DNS_RDATA_INIT; + dns_ttl_t ttl; + isc_result_t result; + + REQUIRE(soardataset != NULL); + REQUIRE(sigsoardataset != NULL); + REQUIRE(p1rdataset != NULL); + REQUIRE(sigp1rdataset != NULL); + + result = dns_rdataset_first(soardataset); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + dns_rdataset_current(soardataset, &rdata); + result = dns_rdata_tostruct(&rdata, &soa, NULL); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + + ttl = ISC_MIN(soa.minimum, soardataset->ttl); + ttl = ISC_MIN(ttl, sigsoardataset->ttl); + ttl = ISC_MIN(ttl, p1rdataset->ttl); + ttl = ISC_MIN(ttl, sigp1rdataset->ttl); + if (p2rdataset != NULL) { + ttl = ISC_MIN(ttl, p2rdataset->ttl); + } + if (sigp2rdataset != NULL) { + ttl = ISC_MIN(ttl, sigp2rdataset->ttl); + } + + return (ttl); +} + +/* + * Synthesize a NODATA response from the SOA and covering NSEC in cache. + */ +static isc_result_t +query_synthnodata(query_ctx_t *qctx, const dns_name_t *signer, + dns_rdataset_t **soardatasetp, + dns_rdataset_t **sigsoardatasetp) { + dns_name_t *name = NULL; + dns_ttl_t ttl; + isc_buffer_t *dbuf, b; + isc_result_t result; + + /* + * Determine the correct TTL to use for the SOA and RRSIG + */ + ttl = query_synthttl(*soardatasetp, *sigsoardatasetp, qctx->rdataset, + qctx->sigrdataset, NULL, NULL); + (*soardatasetp)->ttl = (*sigsoardatasetp)->ttl = ttl; + + /* + * We want the SOA record to be first, so save the + * NODATA proof's name now or else discard it. + */ + if (WANTDNSSEC(qctx->client)) { + ns_client_keepname(qctx->client, qctx->fname, qctx->dbuf); + } else { + ns_client_releasename(qctx->client, &qctx->fname); + } + + dbuf = ns_client_getnamebuf(qctx->client); + if (dbuf == NULL) { + result = ISC_R_NOMEMORY; + goto cleanup; + } + + name = ns_client_newname(qctx->client, dbuf, &b); + if (name == NULL) { + result = ISC_R_NOMEMORY; + goto cleanup; + } + + dns_name_copy(signer, name); + + /* + * Add SOA record. Omit the RRSIG if DNSSEC was not requested. + */ + if (!WANTDNSSEC(qctx->client)) { + sigsoardatasetp = NULL; + } + query_addrrset(qctx, &name, soardatasetp, sigsoardatasetp, dbuf, + DNS_SECTION_AUTHORITY); + + if (WANTDNSSEC(qctx->client)) { + /* + * Add NODATA proof. + */ + query_addrrset(qctx, &qctx->fname, &qctx->rdataset, + &qctx->sigrdataset, NULL, DNS_SECTION_AUTHORITY); + } + + result = ISC_R_SUCCESS; + inc_stats(qctx->client, ns_statscounter_nodatasynth); + +cleanup: + if (name != NULL) { + ns_client_releasename(qctx->client, &name); + } + return (result); +} + +/* + * Synthesize a wildcard answer using the contents of 'rdataset'. + * qctx contains the NODATA proof. + */ +static isc_result_t +query_synthwildcard(query_ctx_t *qctx, dns_rdataset_t *rdataset, + dns_rdataset_t *sigrdataset) { + dns_name_t *name = NULL; + isc_buffer_t *dbuf, b; + isc_result_t result; + dns_rdataset_t *cloneset = NULL, *clonesigset = NULL; + dns_rdataset_t **sigrdatasetp; + + CCTRACE(ISC_LOG_DEBUG(3), "query_synthwildcard"); + + /* + * We want the answer to be first, so save the + * NOQNAME proof's name now or else discard it. + */ + if (WANTDNSSEC(qctx->client)) { + ns_client_keepname(qctx->client, qctx->fname, qctx->dbuf); + } else { + ns_client_releasename(qctx->client, &qctx->fname); + } + + dbuf = ns_client_getnamebuf(qctx->client); + if (dbuf == NULL) { + result = ISC_R_NOMEMORY; + goto cleanup; + } + + name = ns_client_newname(qctx->client, dbuf, &b); + if (name == NULL) { + result = ISC_R_NOMEMORY; + goto cleanup; + } + dns_name_copy(qctx->client->query.qname, name); + + cloneset = ns_client_newrdataset(qctx->client); + if (cloneset == NULL) { + result = ISC_R_NOMEMORY; + goto cleanup; + } + dns_rdataset_clone(rdataset, cloneset); + + /* + * Add answer RRset. Omit the RRSIG if DNSSEC was not requested. + */ + if (WANTDNSSEC(qctx->client)) { + clonesigset = ns_client_newrdataset(qctx->client); + if (clonesigset == NULL) { + result = ISC_R_NOMEMORY; + goto cleanup; + } + dns_rdataset_clone(sigrdataset, clonesigset); + sigrdatasetp = &clonesigset; + } else { + sigrdatasetp = NULL; + } + + query_addrrset(qctx, &name, &cloneset, sigrdatasetp, dbuf, + DNS_SECTION_ANSWER); + + if (WANTDNSSEC(qctx->client)) { + /* + * Add NOQNAME proof. + */ + query_addrrset(qctx, &qctx->fname, &qctx->rdataset, + &qctx->sigrdataset, NULL, DNS_SECTION_AUTHORITY); + } + + result = ISC_R_SUCCESS; + inc_stats(qctx->client, ns_statscounter_wildcardsynth); + +cleanup: + if (name != NULL) { + ns_client_releasename(qctx->client, &name); + } + if (cloneset != NULL) { + ns_client_putrdataset(qctx->client, &cloneset); + } + if (clonesigset != NULL) { + ns_client_putrdataset(qctx->client, &clonesigset); + } + return (result); +} + +/* + * Add a synthesized CNAME record from the wildard RRset (rdataset) + * and NODATA proof by calling query_synthwildcard then setup to + * follow the CNAME. + */ +static isc_result_t +query_synthcnamewildcard(query_ctx_t *qctx, dns_rdataset_t *rdataset, + dns_rdataset_t *sigrdataset) { + isc_result_t result; + dns_name_t *tname = NULL; + dns_rdata_t rdata = DNS_RDATA_INIT; + dns_rdata_cname_t cname; + + result = query_synthwildcard(qctx, rdataset, sigrdataset); + if (result != ISC_R_SUCCESS) { + return (result); + } + + qctx->client->query.attributes |= NS_QUERYATTR_PARTIALANSWER; + + /* + * Reset qname to be the target name of the CNAME and restart + * the query. + */ + result = dns_message_gettempname(qctx->client->message, &tname); + if (result != ISC_R_SUCCESS) { + return (result); + } + + result = dns_rdataset_first(rdataset); + if (result != ISC_R_SUCCESS) { + dns_message_puttempname(qctx->client->message, &tname); + return (result); + } + + dns_rdataset_current(rdataset, &rdata); + result = dns_rdata_tostruct(&rdata, &cname, NULL); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + dns_rdata_reset(&rdata); + + if (dns_name_equal(qctx->client->query.qname, &cname.cname)) { + dns_message_puttempname(qctx->client->message, &tname); + dns_rdata_freestruct(&cname); + return (ISC_R_SUCCESS); + } + + dns_name_copy(&cname.cname, tname); + + dns_rdata_freestruct(&cname); + ns_client_qnamereplace(qctx->client, tname); + qctx->want_restart = true; + if (!WANTRECURSION(qctx->client)) { + qctx->options |= DNS_GETDB_NOLOG; + } + + return (result); +} + +/* + * Synthesize a NXDOMAIN or NODATA response from qctx (which contains the + * NOQNAME proof), nowild + nowildrdataset + signowildrdataset (which + * contains the NOWILDCARD proof or NODATA at wildcard) and + * signer + soardatasetp + sigsoardatasetp which contain the + * SOA record + RRSIG for the negative answer. + */ +static isc_result_t +query_synthnxdomainnodata(query_ctx_t *qctx, bool nodata, dns_name_t *nowild, + dns_rdataset_t *nowildrdataset, + dns_rdataset_t *signowildrdataset, dns_name_t *signer, + dns_rdataset_t **soardatasetp, + dns_rdataset_t **sigsoardatasetp) { + dns_name_t *name = NULL; + dns_ttl_t ttl; + isc_buffer_t *dbuf, b; + isc_result_t result; + dns_rdataset_t *cloneset = NULL, *clonesigset = NULL; + + CCTRACE(ISC_LOG_DEBUG(3), "query_synthnxdomain"); + + /* + * Determine the correct TTL to use for the SOA and RRSIG + */ + ttl = query_synthttl(*soardatasetp, *sigsoardatasetp, qctx->rdataset, + qctx->sigrdataset, nowildrdataset, + signowildrdataset); + (*soardatasetp)->ttl = (*sigsoardatasetp)->ttl = ttl; + + /* + * We want the SOA record to be first, so save the + * NOQNAME proof's name now or else discard it. + */ + if (WANTDNSSEC(qctx->client)) { + ns_client_keepname(qctx->client, qctx->fname, qctx->dbuf); + } else { + ns_client_releasename(qctx->client, &qctx->fname); + } + + dbuf = ns_client_getnamebuf(qctx->client); + if (dbuf == NULL) { + result = ISC_R_NOMEMORY; + goto cleanup; + } + + name = ns_client_newname(qctx->client, dbuf, &b); + if (name == NULL) { + result = ISC_R_NOMEMORY; + goto cleanup; + } + + dns_name_copy(signer, name); + + /* + * Add SOA record. Omit the RRSIG if DNSSEC was not requested. + */ + if (!WANTDNSSEC(qctx->client)) { + sigsoardatasetp = NULL; + } + query_addrrset(qctx, &name, soardatasetp, sigsoardatasetp, dbuf, + DNS_SECTION_AUTHORITY); + + if (WANTDNSSEC(qctx->client)) { + /* + * Add NOQNAME proof. + */ + query_addrrset(qctx, &qctx->fname, &qctx->rdataset, + &qctx->sigrdataset, NULL, DNS_SECTION_AUTHORITY); + + dbuf = ns_client_getnamebuf(qctx->client); + if (dbuf == NULL) { + result = ISC_R_NOMEMORY; + goto cleanup; + } + + name = ns_client_newname(qctx->client, dbuf, &b); + if (name == NULL) { + result = ISC_R_NOMEMORY; + goto cleanup; + } + + dns_name_copy(nowild, name); + + cloneset = ns_client_newrdataset(qctx->client); + clonesigset = ns_client_newrdataset(qctx->client); + if (cloneset == NULL || clonesigset == NULL) { + result = ISC_R_NOMEMORY; + goto cleanup; + } + + dns_rdataset_clone(nowildrdataset, cloneset); + dns_rdataset_clone(signowildrdataset, clonesigset); + + /* + * Add NOWILDCARD proof. + */ + query_addrrset(qctx, &name, &cloneset, &clonesigset, dbuf, + DNS_SECTION_AUTHORITY); + } + + if (nodata) { + inc_stats(qctx->client, ns_statscounter_nodatasynth); + } else { + qctx->client->message->rcode = dns_rcode_nxdomain; + inc_stats(qctx->client, ns_statscounter_nxdomainsynth); + } + result = ISC_R_SUCCESS; + +cleanup: + if (name != NULL) { + ns_client_releasename(qctx->client, &name); + } + if (cloneset != NULL) { + ns_client_putrdataset(qctx->client, &cloneset); + } + if (clonesigset != NULL) { + ns_client_putrdataset(qctx->client, &clonesigset); + } + return (result); +} + +/* + * Check that all signer names in sigrdataset match the expected signer. + */ +static isc_result_t +checksignames(dns_name_t *signer, dns_rdataset_t *sigrdataset) { + isc_result_t result; + + for (result = dns_rdataset_first(sigrdataset); result == ISC_R_SUCCESS; + result = dns_rdataset_next(sigrdataset)) + { + dns_rdata_t rdata = DNS_RDATA_INIT; + dns_rdata_rrsig_t rrsig; + + dns_rdataset_current(sigrdataset, &rdata); + result = dns_rdata_tostruct(&rdata, &rrsig, NULL); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + if (dns_name_countlabels(signer) == 0) { + dns_name_copy(&rrsig.signer, signer); + } else if (!dns_name_equal(signer, &rrsig.signer)) { + return (ISC_R_FAILURE); + } + } + + return (ISC_R_SUCCESS); +} + +/*% + * Handle covering NSEC responses. + * + * Verify the NSEC record is appropriate for the QNAME; if not, + * redo the initial query without DNS_DBFIND_COVERINGNSEC. + * + * If the covering NSEC proves that the name exists but not the type, + * synthesize a NODATA response. + * + * If the name doesn't exist, compute the wildcard record and check whether + * the wildcard name exists or not. If we can't determine this, redo the + * initial query without DNS_DBFIND_COVERINGNSEC. + * + * If the wildcard name does not exist, compute the SOA name and look that + * up. If the SOA record does not exist, redo the initial query without + * DNS_DBFIND_COVERINGNSEC. If the SOA record exists, synthesize an + * NXDOMAIN response from the found records. + * + * If the wildcard name does exist, perform a lookup for the requested + * type at the wildcard name. + */ +static isc_result_t +query_coveringnsec(query_ctx_t *qctx) { + dns_db_t *db = NULL; + dns_clientinfo_t ci; + dns_clientinfomethods_t cm; + dns_dbnode_t *node = NULL; + dns_fixedname_t fixed; + dns_fixedname_t fnamespace; + dns_fixedname_t fnowild; + dns_fixedname_t fsigner; + dns_fixedname_t fwild; + dns_name_t *fname = NULL; + dns_name_t *namespace = NULL; + dns_name_t *nowild = NULL; + dns_name_t *signer = NULL; + dns_name_t *wild = NULL; + dns_name_t qname; + dns_rdataset_t *soardataset = NULL, *sigsoardataset = NULL; + dns_rdataset_t rdataset, sigrdataset; + bool done = false; + bool exists = true, data = true; + bool redirected = false; + isc_result_t result = ISC_R_SUCCESS; + unsigned int dboptions = qctx->client->query.dboptions; + unsigned int labels; + + CCTRACE(ISC_LOG_DEBUG(3), "query_coveringnsec"); + + dns_name_init(&qname, NULL); + dns_rdataset_init(&rdataset); + dns_rdataset_init(&sigrdataset); + namespace = dns_fixedname_initname(&fnamespace); + + /* + * Check that the NSEC record is from the correct namespace. + * For records that belong to the parent zone (i.e. DS), + * remove a label to find the correct namespace. + */ + dns_name_clone(qctx->client->query.qname, &qname); + labels = dns_name_countlabels(&qname); + if (dns_rdatatype_atparent(qctx->qtype) && labels > 1) { + dns_name_getlabelsequence(&qname, 1, labels - 1, &qname); + } + dns_view_sfd_find(qctx->view, &qname, namespace); + if (!dns_name_issubdomain(qctx->fname, namespace)) { + goto cleanup; + } + + /* + * If we have no signer name, stop immediately. + */ + if (!dns_rdataset_isassociated(qctx->sigrdataset)) { + goto cleanup; + } + + wild = dns_fixedname_initname(&fwild); + fname = dns_fixedname_initname(&fixed); + signer = dns_fixedname_initname(&fsigner); + nowild = dns_fixedname_initname(&fnowild); + + dns_clientinfomethods_init(&cm, ns_client_sourceip); + dns_clientinfo_init(&ci, qctx->client, NULL); + + /* + * All signer names must be the same to accept. + */ + result = checksignames(signer, qctx->sigrdataset); + if (result != ISC_R_SUCCESS) { + result = ISC_R_SUCCESS; + goto cleanup; + } + + /* + * If NSEC or RRSIG are missing from the type map + * reject the NSEC RRset. + */ + if (!dns_nsec_requiredtypespresent(qctx->rdataset)) { + goto cleanup; + } + + /* + * Check that we have the correct NOQNAME NSEC record. + */ + result = dns_nsec_noexistnodata(qctx->qtype, qctx->client->query.qname, + qctx->fname, qctx->rdataset, &exists, + &data, wild, log_noexistnodata, qctx); + + if (result != ISC_R_SUCCESS || (exists && data)) { + goto cleanup; + } + + if (exists) { + if (qctx->type == dns_rdatatype_any) { /* XXX not yet */ + goto cleanup; + } + if (!ISC_LIST_EMPTY(qctx->view->dns64) && + (qctx->type == dns_rdatatype_a || + qctx->type == dns_rdatatype_aaaa)) /* XXX not yet */ + { + goto cleanup; + } + if (!qctx->resuming && !STALE(qctx->rdataset) && + qctx->rdataset->ttl == 0 && RECURSIONOK(qctx->client)) + { + goto cleanup; + } + + soardataset = ns_client_newrdataset(qctx->client); + sigsoardataset = ns_client_newrdataset(qctx->client); + if (soardataset == NULL || sigsoardataset == NULL) { + goto cleanup; + } + + /* + * Look for SOA record to construct NODATA response. + */ + dns_db_attach(qctx->db, &db); + result = dns_db_findext(db, signer, qctx->version, + dns_rdatatype_soa, dboptions, + qctx->client->now, &node, fname, &cm, + &ci, soardataset, sigsoardataset); + + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + (void)query_synthnodata(qctx, signer, &soardataset, + &sigsoardataset); + done = true; + goto cleanup; + } + + /* + * Look up the no-wildcard proof. + */ + dns_db_attach(qctx->db, &db); + result = dns_db_findext(db, wild, qctx->version, qctx->type, + dboptions | DNS_DBFIND_COVERINGNSEC, + qctx->client->now, &node, nowild, &cm, &ci, + &rdataset, &sigrdataset); + + if (rdataset.trust != dns_trust_secure || + sigrdataset.trust != dns_trust_secure) + { + goto cleanup; + } + + /* + * Zero TTL handling of wildcard record. + * + * We don't yet have code to handle synthesis and type ANY or dns64 + * processing so we abort the synthesis here if there would be a + * interaction. + */ + switch (result) { + case ISC_R_SUCCESS: + if (qctx->type == dns_rdatatype_any) { /* XXX not yet */ + goto cleanup; + } + if (!ISC_LIST_EMPTY(qctx->view->dns64) && + (qctx->type == dns_rdatatype_a || + qctx->type == dns_rdatatype_aaaa)) /* XXX not yet */ + { + goto cleanup; + } + FALLTHROUGH; + case DNS_R_CNAME: + if (!qctx->resuming && !STALE(&rdataset) && rdataset.ttl == 0 && + RECURSIONOK(qctx->client)) + { + goto cleanup; + } + default: + break; + } + + switch (result) { + case DNS_R_COVERINGNSEC: + /* + * Check that the covering NSEC record is from the right + * namespace. + */ + if (!dns_name_issubdomain(nowild, namespace)) { + goto cleanup; + } + result = dns_nsec_noexistnodata(qctx->qtype, wild, nowild, + &rdataset, &exists, &data, NULL, + log_noexistnodata, qctx); + if (result != ISC_R_SUCCESS || (exists && data)) { + goto cleanup; + } + break; + case ISC_R_SUCCESS: /* wild card match */ + (void)query_synthwildcard(qctx, &rdataset, &sigrdataset); + done = true; + goto cleanup; + case DNS_R_CNAME: /* wild card cname */ + (void)query_synthcnamewildcard(qctx, &rdataset, &sigrdataset); + done = true; + goto cleanup; + case DNS_R_NCACHENXRRSET: /* wild card nodata */ + case DNS_R_NCACHENXDOMAIN: /* direct nxdomain */ + default: + goto cleanup; + } + + /* + * We now have the proof that we have an NXDOMAIN. Apply + * NXDOMAIN redirection if configured. + */ + result = query_redirect(qctx); + if (result != ISC_R_COMPLETE) { + redirected = true; + goto cleanup; + } + + /* + * Must be signed to accept. + */ + if (!dns_rdataset_isassociated(&sigrdataset)) { + goto cleanup; + } + + /* + * Check signer signer names again. + */ + result = checksignames(signer, &sigrdataset); + if (result != ISC_R_SUCCESS) { + result = ISC_R_SUCCESS; + goto cleanup; + } + + if (node != NULL) { + dns_db_detachnode(db, &node); + } + + soardataset = ns_client_newrdataset(qctx->client); + sigsoardataset = ns_client_newrdataset(qctx->client); + if (soardataset == NULL || sigsoardataset == NULL) { + goto cleanup; + } + + /* + * Look for SOA record to construct NXDOMAIN response. + */ + result = dns_db_findext(db, signer, qctx->version, dns_rdatatype_soa, + dboptions, qctx->client->now, &node, fname, &cm, + &ci, soardataset, sigsoardataset); + + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + (void)query_synthnxdomainnodata(qctx, exists, nowild, &rdataset, + &sigrdataset, signer, &soardataset, + &sigsoardataset); + done = true; + +cleanup: + if (dns_rdataset_isassociated(&rdataset)) { + dns_rdataset_disassociate(&rdataset); + } + if (dns_rdataset_isassociated(&sigrdataset)) { + dns_rdataset_disassociate(&sigrdataset); + } + if (soardataset != NULL) { + ns_client_putrdataset(qctx->client, &soardataset); + } + if (sigsoardataset != NULL) { + ns_client_putrdataset(qctx->client, &sigsoardataset); + } + if (db != NULL) { + if (node != NULL) { + dns_db_detachnode(db, &node); + } + dns_db_detach(&db); + } + + if (redirected) { + return (result); + } + + if (!done) { + /* + * No covering NSEC was found; proceed with recursion. + */ + qctx->findcoveringnsec = false; + if (qctx->fname != NULL) { + ns_client_releasename(qctx->client, &qctx->fname); + } + if (qctx->node != NULL) { + dns_db_detachnode(qctx->db, &qctx->node); + } + ns_client_putrdataset(qctx->client, &qctx->rdataset); + if (qctx->sigrdataset != NULL) { + ns_client_putrdataset(qctx->client, &qctx->sigrdataset); + } + return (query_lookup(qctx)); + } + + return (ns_query_done(qctx)); +} + +/*% + * Handle negative cache responses, DNS_R_NCACHENXRRSET or + * DNS_R_NCACHENXDOMAIN. (Note: may also be called with result + * set to DNS_R_NXDOMAIN when handling DNS64 lookups.) + */ +static isc_result_t +query_ncache(query_ctx_t *qctx, isc_result_t result) { + INSIST(!qctx->is_zone); + INSIST(result == DNS_R_NCACHENXDOMAIN || + result == DNS_R_NCACHENXRRSET || result == DNS_R_NXDOMAIN); + + CCTRACE(ISC_LOG_DEBUG(3), "query_ncache"); + + CALL_HOOK(NS_QUERY_NCACHE_BEGIN, qctx); + + qctx->authoritative = false; + + if (result == DNS_R_NCACHENXDOMAIN) { + /* + * Set message rcode. (This is not done when + * result == DNS_R_NXDOMAIN because that means we're + * being called after a DNS64 lookup and don't want + * to update the rcode now.) + */ + qctx->client->message->rcode = dns_rcode_nxdomain; + + /* Look for RFC 1918 leakage from Internet. */ + if (qctx->qtype == dns_rdatatype_ptr && + qctx->client->message->rdclass == dns_rdataclass_in && + dns_name_countlabels(qctx->fname) == 7) + { + warn_rfc1918(qctx->client, qctx->fname, qctx->rdataset); + } + } + + return (query_nodata(qctx, result)); + +cleanup: + return (result); +} + +/* + * If we have a zero ttl from the cache, refetch. + */ +static isc_result_t +query_zerottl_refetch(query_ctx_t *qctx) { + isc_result_t result; + + CCTRACE(ISC_LOG_DEBUG(3), "query_zerottl_refetch"); + + if (qctx->is_zone || qctx->resuming || STALE(qctx->rdataset) || + qctx->rdataset->ttl != 0 || !RECURSIONOK(qctx->client)) + { + return (ISC_R_COMPLETE); + } + + qctx_clean(qctx); + + INSIST(!REDIRECT(qctx->client)); + + result = ns_query_recurse(qctx->client, qctx->qtype, + qctx->client->query.qname, NULL, NULL, + qctx->resuming); + if (result == ISC_R_SUCCESS) { + CALL_HOOK(NS_QUERY_ZEROTTL_RECURSE, qctx); + qctx->client->query.attributes |= NS_QUERYATTR_RECURSING; + + if (qctx->dns64) { + qctx->client->query.attributes |= NS_QUERYATTR_DNS64; + } + if (qctx->dns64_exclude) { + qctx->client->query.attributes |= + NS_QUERYATTR_DNS64EXCLUDE; + } + } else { + /* + * There was a zero ttl from the cache, don't fallback to + * serve-stale lookup. + */ + QUERY_ERROR(qctx, result); + } + + return (ns_query_done(qctx)); + +cleanup: + return (result); +} + +/* + * Handle CNAME responses. + */ +static isc_result_t +query_cname(query_ctx_t *qctx) { + isc_result_t result = ISC_R_UNSET; + dns_name_t *tname = NULL; + dns_rdataset_t *trdataset = NULL; + dns_rdataset_t **sigrdatasetp = NULL; + dns_rdata_t rdata = DNS_RDATA_INIT; + dns_rdata_cname_t cname; + + CCTRACE(ISC_LOG_DEBUG(3), "query_cname"); + + CALL_HOOK(NS_QUERY_CNAME_BEGIN, qctx); + + result = query_zerottl_refetch(qctx); + if (result != ISC_R_COMPLETE) { + return (result); + } + + /* + * 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 = qctx->rdataset; + + /* + * Add the CNAME to the answer section. + */ + if (WANTDNSSEC(qctx->client) && qctx->sigrdataset != NULL) { + sigrdatasetp = &qctx->sigrdataset; + } + + if (WANTDNSSEC(qctx->client) && + (qctx->fname->attributes & DNS_NAMEATTR_WILDCARD) != 0) + { + dns_fixedname_init(&qctx->wildcardname); + dns_name_copy(qctx->fname, + dns_fixedname_name(&qctx->wildcardname)); + qctx->need_wildcardproof = true; + } + + if (NOQNAME(qctx->rdataset) && WANTDNSSEC(qctx->client)) { + qctx->noqname = qctx->rdataset; + } else { + qctx->noqname = NULL; + } + + if (!qctx->is_zone && RECURSIONOK(qctx->client)) { + query_prefetch(qctx->client, qctx->fname, qctx->rdataset); + } + + query_addrrset(qctx, &qctx->fname, &qctx->rdataset, sigrdatasetp, + qctx->dbuf, DNS_SECTION_ANSWER); + + query_addnoqnameproof(qctx); + + /* + * We set the PARTIALANSWER attribute so that if anything goes + * wrong later on, we'll return what we've got so far. + */ + qctx->client->query.attributes |= NS_QUERYATTR_PARTIALANSWER; + + /* + * Reset qname to be the target name of the CNAME and restart + * the query. + */ + result = dns_message_gettempname(qctx->client->message, &tname); + if (result != ISC_R_SUCCESS) { + return (ns_query_done(qctx)); + } + + result = dns_rdataset_first(trdataset); + if (result != ISC_R_SUCCESS) { + dns_message_puttempname(qctx->client->message, &tname); + return (ns_query_done(qctx)); + } + + dns_rdataset_current(trdataset, &rdata); + result = dns_rdata_tostruct(&rdata, &cname, NULL); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + dns_rdata_reset(&rdata); + + dns_name_copy(&cname.cname, tname); + + dns_rdata_freestruct(&cname); + ns_client_qnamereplace(qctx->client, tname); + qctx->want_restart = true; + if (!WANTRECURSION(qctx->client)) { + qctx->options |= DNS_GETDB_NOLOG; + } + + query_addauth(qctx); + + return (ns_query_done(qctx)); + +cleanup: + return (result); +} + +/* + * Handle DNAME responses. + */ +static isc_result_t +query_dname(query_ctx_t *qctx) { + dns_name_t *tname, *prefix; + dns_rdata_t rdata = DNS_RDATA_INIT; + dns_rdata_dname_t dname; + dns_fixedname_t fixed; + dns_rdataset_t *trdataset; + dns_rdataset_t **sigrdatasetp = NULL; + dns_namereln_t namereln; + isc_buffer_t b; + int order; + isc_result_t result = ISC_R_UNSET; + unsigned int nlabels; + + CCTRACE(ISC_LOG_DEBUG(3), "query_dname"); + + CALL_HOOK(NS_QUERY_DNAME_BEGIN, qctx); + + /* + * 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(qctx->client->query.qname, qctx->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 = qctx->rdataset; + + /* + * Add the DNAME to the answer section. + */ + if (WANTDNSSEC(qctx->client) && qctx->sigrdataset != NULL) { + sigrdatasetp = &qctx->sigrdataset; + } + + if (WANTDNSSEC(qctx->client) && + (qctx->fname->attributes & DNS_NAMEATTR_WILDCARD) != 0) + { + dns_fixedname_init(&qctx->wildcardname); + dns_name_copy(qctx->fname, + dns_fixedname_name(&qctx->wildcardname)); + qctx->need_wildcardproof = true; + } + + if (!qctx->is_zone && RECURSIONOK(qctx->client)) { + query_prefetch(qctx->client, qctx->fname, qctx->rdataset); + } + query_addrrset(qctx, &qctx->fname, &qctx->rdataset, sigrdatasetp, + qctx->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. + */ + qctx->client->query.attributes |= NS_QUERYATTR_PARTIALANSWER; + + /* + * Get the target name of the DNAME. + */ + tname = NULL; + result = dns_message_gettempname(qctx->client->message, &tname); + if (result != ISC_R_SUCCESS) { + return (ns_query_done(qctx)); + } + + result = dns_rdataset_first(trdataset); + if (result != ISC_R_SUCCESS) { + dns_message_puttempname(qctx->client->message, &tname); + return (ns_query_done(qctx)); + } + + dns_rdataset_current(trdataset, &rdata); + result = dns_rdata_tostruct(&rdata, &dname, NULL); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + dns_rdata_reset(&rdata); + + dns_name_copy(&dname.dname, tname); + dns_rdata_freestruct(&dname); + + /* + * Construct the new qname consisting of + * <found name prefix>.<dname target> + */ + prefix = dns_fixedname_initname(&fixed); + dns_name_split(qctx->client->query.qname, nlabels, prefix, NULL); + INSIST(qctx->fname == NULL); + qctx->dbuf = ns_client_getnamebuf(qctx->client); + if (qctx->dbuf == NULL) { + dns_message_puttempname(qctx->client->message, &tname); + return (ns_query_done(qctx)); + } + qctx->fname = ns_client_newname(qctx->client, qctx->dbuf, &b); + if (qctx->fname == NULL) { + dns_message_puttempname(qctx->client->message, &tname); + return (ns_query_done(qctx)); + } + result = dns_name_concatenate(prefix, tname, qctx->fname, NULL); + dns_message_puttempname(qctx->client->message, &tname); + + /* + * RFC2672, section 4.1, subsection 3c says + * we should return YXDOMAIN if the constructed + * name would be too long. + */ + if (result == DNS_R_NAMETOOLONG) { + qctx->client->message->rcode = dns_rcode_yxdomain; + } + if (result != ISC_R_SUCCESS) { + return (ns_query_done(qctx)); + } + + ns_client_keepname(qctx->client, qctx->fname, qctx->dbuf); + + /* + * Synthesize a CNAME consisting of + * <old qname> <dname ttl> CNAME <new qname> + * with <dname trust value> + * + * Synthesize a CNAME so old old clients that don't understand + * DNAME can chain. + * + * 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. + */ + result = query_addcname(qctx, trdataset->trust, trdataset->ttl); + if (result != ISC_R_SUCCESS) { + return (ns_query_done(qctx)); + } + + /* + * If the original query was not for a CNAME or ANY then follow the + * CNAME. + */ + if (qctx->qtype != dns_rdatatype_cname && + qctx->qtype != dns_rdatatype_any) + { + /* + * Switch to the new qname and restart. + */ + ns_client_qnamereplace(qctx->client, qctx->fname); + qctx->fname = NULL; + qctx->want_restart = true; + if (!WANTRECURSION(qctx->client)) { + qctx->options |= DNS_GETDB_NOLOG; + } + } + + query_addauth(qctx); + + return (ns_query_done(qctx)); + +cleanup: + return (result); +} + +/*% + * Add CNAME to response. + */ +static isc_result_t +query_addcname(query_ctx_t *qctx, dns_trust_t trust, dns_ttl_t ttl) { + ns_client_t *client = qctx->client; + dns_rdataset_t *rdataset = NULL; + dns_rdatalist_t *rdatalist = NULL; + dns_rdata_t *rdata = NULL; + isc_region_t r; + dns_name_t *aname = NULL; + isc_result_t result; + + result = dns_message_gettempname(client->message, &aname); + if (result != ISC_R_SUCCESS) { + return (result); + } + + dns_name_copy(client->query.qname, aname); + + result = dns_message_gettemprdatalist(client->message, &rdatalist); + if (result != ISC_R_SUCCESS) { + dns_message_puttempname(client->message, &aname); + return (result); + } + + result = dns_message_gettemprdata(client->message, &rdata); + if (result != ISC_R_SUCCESS) { + dns_message_puttempname(client->message, &aname); + dns_message_puttemprdatalist(client->message, &rdatalist); + return (result); + } + + result = dns_message_gettemprdataset(client->message, &rdataset); + if (result != ISC_R_SUCCESS) { + dns_message_puttempname(client->message, &aname); + dns_message_puttemprdatalist(client->message, &rdatalist); + dns_message_puttemprdata(client->message, &rdata); + return (result); + } + + rdatalist->type = dns_rdatatype_cname; + rdatalist->rdclass = client->message->rdclass; + rdatalist->ttl = ttl; + + dns_name_toregion(qctx->fname, &r); + rdata->data = r.base; + rdata->length = r.length; + rdata->rdclass = client->message->rdclass; + rdata->type = dns_rdatatype_cname; + + ISC_LIST_APPEND(rdatalist->rdata, rdata, link); + RUNTIME_CHECK(dns_rdatalist_tordataset(rdatalist, rdataset) == + ISC_R_SUCCESS); + rdataset->trust = trust; + dns_rdataset_setownercase(rdataset, aname); + + query_addrrset(qctx, &aname, &rdataset, NULL, NULL, DNS_SECTION_ANSWER); + if (rdataset != NULL) { + if (dns_rdataset_isassociated(rdataset)) { + dns_rdataset_disassociate(rdataset); + } + dns_message_puttemprdataset(client->message, &rdataset); + } + if (aname != NULL) { + dns_message_puttempname(client->message, &aname); + } + + return (ISC_R_SUCCESS); +} + +/*% + * Prepare to respond: determine whether a wildcard proof is needed, + * then hand off to query_respond() or (for type ANY queries) + * query_respond_any(). + */ +static isc_result_t +query_prepresponse(query_ctx_t *qctx) { + isc_result_t result = ISC_R_UNSET; + + CCTRACE(ISC_LOG_DEBUG(3), "query_prepresponse"); + + CALL_HOOK(NS_QUERY_PREP_RESPONSE_BEGIN, qctx); + + if (WANTDNSSEC(qctx->client) && + (qctx->fname->attributes & DNS_NAMEATTR_WILDCARD) != 0) + { + dns_fixedname_init(&qctx->wildcardname); + dns_name_copy(qctx->fname, + dns_fixedname_name(&qctx->wildcardname)); + qctx->need_wildcardproof = true; + } + + if (qctx->type == dns_rdatatype_any) { + return (query_respond_any(qctx)); + } + + result = query_zerottl_refetch(qctx); + if (result != ISC_R_COMPLETE) { + return (result); + } + + return (query_respond(qctx)); + +cleanup: + return (result); +} + +/*% + * Add SOA to the authority section when sending negative responses + * (or to the additional section if sending negative responses triggered + * by RPZ rewriting.) + */ +static isc_result_t +query_addsoa(query_ctx_t *qctx, unsigned int override_ttl, + dns_section_t section) { + ns_client_t *client = qctx->client; + dns_name_t *name = NULL; + dns_dbnode_t *node = NULL; + isc_result_t result, eresult = ISC_R_SUCCESS; + dns_rdataset_t *rdataset = NULL, *sigrdataset = NULL; + dns_rdataset_t **sigrdatasetp = NULL; + dns_clientinfomethods_t cm; + dns_clientinfo_t ci; + + CTRACE(ISC_LOG_DEBUG(3), "query_addsoa"); + + dns_clientinfomethods_init(&cm, ns_client_sourceip); + dns_clientinfo_init(&ci, client, NULL); + + /* + * Don't add the SOA record for test which set "-T nosoa". + */ + if (((client->sctx->options & NS_SERVER_NOSOA) != 0) && + (!WANTDNSSEC(client) || !dns_rdataset_isassociated(qctx->rdataset))) + { + return (ISC_R_SUCCESS); + } + + /* + * Get resources and make 'name' be the database origin. + */ + result = dns_message_gettempname(client->message, &name); + if (result != ISC_R_SUCCESS) { + return (result); + } + + /* + * We'll be releasing 'name' before returning, so it's safe to + * use clone instead of copying here. + */ + dns_name_clone(dns_db_origin(qctx->db), name); + + rdataset = ns_client_newrdataset(client); + if (rdataset == NULL) { + CTRACE(ISC_LOG_ERROR, "unable to allocate rdataset"); + eresult = DNS_R_SERVFAIL; + goto cleanup; + } + if (WANTDNSSEC(client) && dns_db_issecure(qctx->db)) { + sigrdataset = ns_client_newrdataset(client); + if (sigrdataset == NULL) { + CTRACE(ISC_LOG_ERROR, "unable to allocate sigrdataset"); + eresult = DNS_R_SERVFAIL; + goto cleanup; + } + } + + /* + * Find the SOA. + */ + result = dns_db_getoriginnode(qctx->db, &node); + if (result == ISC_R_SUCCESS) { + result = dns_db_findrdataset(qctx->db, node, qctx->version, + dns_rdatatype_soa, 0, client->now, + rdataset, sigrdataset); + } else { + dns_fixedname_t foundname; + dns_name_t *fname; + + fname = dns_fixedname_initname(&foundname); + + result = dns_db_findext(qctx->db, name, qctx->version, + dns_rdatatype_soa, + client->query.dboptions, 0, &node, + fname, &cm, &ci, 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! + */ + CTRACE(ISC_LOG_ERROR, "unable to find SOA RR at zone apex"); + 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); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + + if (override_ttl != UINT32_MAX && override_ttl < rdataset->ttl) + { + rdataset->ttl = override_ttl; + if (sigrdataset != NULL) { + sigrdataset->ttl = override_ttl; + } + } + + /* + * 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; + } + + if (section == DNS_SECTION_ADDITIONAL) { + rdataset->attributes |= DNS_RDATASETATTR_REQUIRED; + } + query_addrrset(qctx, &name, &rdataset, sigrdatasetp, NULL, + section); + } + +cleanup: + ns_client_putrdataset(client, &rdataset); + if (sigrdataset != NULL) { + ns_client_putrdataset(client, &sigrdataset); + } + if (name != NULL) { + ns_client_releasename(client, &name); + } + if (node != NULL) { + dns_db_detachnode(qctx->db, &node); + } + + return (eresult); +} + +/*% + * Add NS to authority section (used when the zone apex is already known). + */ +static isc_result_t +query_addns(query_ctx_t *qctx) { + ns_client_t *client = qctx->client; + isc_result_t result, eresult; + dns_name_t *name = NULL, *fname; + dns_dbnode_t *node = NULL; + dns_fixedname_t foundname; + dns_rdataset_t *rdataset = NULL, *sigrdataset = NULL; + dns_rdataset_t **sigrdatasetp = NULL; + dns_clientinfomethods_t cm; + dns_clientinfo_t ci; + + CTRACE(ISC_LOG_DEBUG(3), "query_addns"); + + /* + * Initialization. + */ + eresult = ISC_R_SUCCESS; + fname = dns_fixedname_initname(&foundname); + + dns_clientinfomethods_init(&cm, ns_client_sourceip); + dns_clientinfo_init(&ci, client, NULL); + + /* + * Get resources and make 'name' be the database origin. + */ + result = dns_message_gettempname(client->message, &name); + if (result != ISC_R_SUCCESS) { + CTRACE(ISC_LOG_DEBUG(3), "query_addns: dns_message_gettempname " + "failed: done"); + return (result); + } + dns_name_clone(dns_db_origin(qctx->db), name); + rdataset = ns_client_newrdataset(client); + if (rdataset == NULL) { + CTRACE(ISC_LOG_ERROR, "query_addns: ns_client_newrdataset " + "failed"); + eresult = DNS_R_SERVFAIL; + goto cleanup; + } + + if (WANTDNSSEC(client) && dns_db_issecure(qctx->db)) { + sigrdataset = ns_client_newrdataset(client); + if (sigrdataset == NULL) { + CTRACE(ISC_LOG_ERROR, "query_addns: " + "ns_client_newrdataset failed"); + eresult = DNS_R_SERVFAIL; + goto cleanup; + } + } + + /* + * Find the NS rdataset. + */ + result = dns_db_getoriginnode(qctx->db, &node); + if (result == ISC_R_SUCCESS) { + result = dns_db_findrdataset(qctx->db, node, qctx->version, + dns_rdatatype_ns, 0, client->now, + rdataset, sigrdataset); + } else { + CTRACE(ISC_LOG_DEBUG(3), "query_addns: calling dns_db_find"); + result = dns_db_findext(qctx->db, name, NULL, dns_rdatatype_ns, + client->query.dboptions, 0, &node, + fname, &cm, &ci, rdataset, sigrdataset); + CTRACE(ISC_LOG_DEBUG(3), "query_addns: dns_db_find complete"); + } + if (result != ISC_R_SUCCESS) { + CTRACE(ISC_LOG_ERROR, "query_addns: " + "dns_db_findrdataset or 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; + } + query_addrrset(qctx, &name, &rdataset, sigrdatasetp, NULL, + DNS_SECTION_AUTHORITY); + } + +cleanup: + CTRACE(ISC_LOG_DEBUG(3), "query_addns: cleanup"); + ns_client_putrdataset(client, &rdataset); + if (sigrdataset != NULL) { + ns_client_putrdataset(client, &sigrdataset); + } + if (name != NULL) { + ns_client_releasename(client, &name); + } + if (node != NULL) { + dns_db_detachnode(qctx->db, &node); + } + + CTRACE(ISC_LOG_DEBUG(3), "query_addns: done"); + return (eresult); +} + +/*% + * Find the zone cut and add the best NS rrset to the authority section. + */ +static void +query_addbestns(query_ctx_t *qctx) { + ns_client_t *client = qctx->client; + dns_db_t *db = NULL, *zdb = NULL; + dns_dbnode_t *node = NULL; + dns_name_t *fname = NULL, *zfname = NULL; + dns_rdataset_t *rdataset = NULL, *sigrdataset = NULL; + dns_rdataset_t *zrdataset = NULL, *zsigrdataset = NULL; + bool is_zone = false, use_zone = false; + isc_buffer_t *dbuf = NULL; + isc_result_t result; + dns_dbversion_t *version = NULL; + dns_zone_t *zone = NULL; + isc_buffer_t b; + dns_clientinfomethods_t cm; + dns_clientinfo_t ci; + + CTRACE(ISC_LOG_DEBUG(3), "query_addbestns"); + + dns_clientinfomethods_init(&cm, ns_client_sourceip); + dns_clientinfo_init(&ci, client, NULL); + + /* + * 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 = ns_client_getnamebuf(client); + if (dbuf == NULL) { + goto cleanup; + } + fname = ns_client_newname(client, dbuf, &b); + rdataset = ns_client_newrdataset(client); + if (fname == NULL || rdataset == NULL) { + goto cleanup; + } + + /* + * Get the RRSIGs if the client requested them or if we may + * need to validate answers from the cache. + */ + if (WANTDNSSEC(client) || !is_zone) { + sigrdataset = ns_client_newrdataset(client); + if (sigrdataset == NULL) { + goto cleanup; + } + } + + /* + * Now look for the zonecut. + */ + if (is_zone) { + result = dns_db_findext( + db, client->query.qname, version, dns_rdatatype_ns, + client->query.dboptions, client->now, &node, fname, &cm, + &ci, rdataset, sigrdataset); + if (result != DNS_R_DELEGATION) { + goto cleanup; + } + if (USECACHE(client)) { + ns_client_keepname(client, fname, dbuf); + dns_db_detachnode(db, &node); + SAVE(zdb, db); + SAVE(zfname, fname); + SAVE(zrdataset, rdataset); + SAVE(zsigrdataset, sigrdataset); + version = NULL; + dns_db_attach(client->view->cachedb, &db); + is_zone = false; + goto db_find; + } + } else { + result = dns_db_findzonecut( + db, client->query.qname, client->query.dboptions, + client->now, &node, fname, NULL, 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 = 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 = true; + } else { + goto cleanup; + } + } + + if (use_zone) { + ns_client_releasename(client, &fname); + /* + * We've already done ns_client_keepname() on + * zfname, so we must set dbuf to NULL to + * prevent query_addrrset() from trying to + * call ns_client_keepname() again. + */ + dbuf = NULL; + ns_client_putrdataset(client, &rdataset); + if (sigrdataset != NULL) { + ns_client_putrdataset(client, &sigrdataset); + } + + if (node != NULL) { + dns_db_detachnode(db, &node); + } + dns_db_detach(&db); + + RESTORE(db, zdb); + RESTORE(fname, zfname); + RESTORE(rdataset, zrdataset); + RESTORE(sigrdataset, zsigrdataset); + } + + /* + * Attempt to validate RRsets that are pending or that are glue. + */ + if ((DNS_TRUST_PENDING(rdataset->trust) || + (sigrdataset != NULL && DNS_TRUST_PENDING(sigrdataset->trust))) && + !validate(client, db, fname, rdataset, sigrdataset) && + !PENDINGOK(client->query.dboptions)) + { + goto cleanup; + } + + if ((DNS_TRUST_GLUE(rdataset->trust) || + (sigrdataset != NULL && DNS_TRUST_GLUE(sigrdataset->trust))) && + !validate(client, db, fname, rdataset, sigrdataset) && + SECURE(client) && WANTDNSSEC(client)) + { + goto cleanup; + } + + /* + * If the answer is secure only add NS records if they are secure + * when the client may be looking for AD in the response. + */ + if (SECURE(client) && (WANTDNSSEC(client) || WANTAD(client)) && + ((rdataset->trust != dns_trust_secure) || + (sigrdataset != NULL && sigrdataset->trust != dns_trust_secure))) + { + goto cleanup; + } + + /* + * If the client doesn't want DNSSEC we can discard the sigrdataset + * now. + */ + if (!WANTDNSSEC(client)) { + ns_client_putrdataset(client, &sigrdataset); + } + + query_addrrset(qctx, &fname, &rdataset, &sigrdataset, dbuf, + DNS_SECTION_AUTHORITY); + +cleanup: + if (rdataset != NULL) { + ns_client_putrdataset(client, &rdataset); + } + if (sigrdataset != NULL) { + ns_client_putrdataset(client, &sigrdataset); + } + if (fname != NULL) { + ns_client_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) { + ns_client_putrdataset(client, &zrdataset); + if (zsigrdataset != NULL) { + ns_client_putrdataset(client, &zsigrdataset); + } + if (zfname != NULL) { + ns_client_releasename(client, &zfname); + } + dns_db_detach(&zdb); + } +} + +static void +query_addwildcardproof(query_ctx_t *qctx, bool ispositive, bool nodata) { + ns_client_t *client = qctx->client; + isc_buffer_t *dbuf, b; + dns_name_t *name; + dns_name_t *fname = NULL; + dns_rdataset_t *rdataset = NULL, *sigrdataset = NULL; + dns_fixedname_t wfixed; + dns_name_t *wname; + dns_dbnode_t *node = NULL; + unsigned int options; + unsigned int olabels, nlabels, labels; + isc_result_t result; + dns_rdata_t rdata = DNS_RDATA_INIT; + dns_rdata_nsec_t nsec; + bool have_wname; + int order; + dns_fixedname_t cfixed; + dns_name_t *cname; + dns_clientinfomethods_t cm; + dns_clientinfo_t ci; + + CTRACE(ISC_LOG_DEBUG(3), "query_addwildcardproof"); + + dns_clientinfomethods_init(&cm, ns_client_sourceip); + dns_clientinfo_init(&ci, client, NULL); + + /* + * If a name has been specifically flagged as needing + * a wildcard proof then it will have been copied to + * qctx->wildcardname. Otherwise we just use the client + * QNAME. + */ + if (qctx->need_wildcardproof) { + name = dns_fixedname_name(&qctx->wildcardname); + } else { + name = client->query.qname; + } + + /* + * Get the NOQNAME proof then if !ispositive + * 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 *.example + */ + options = client->query.dboptions | DNS_DBFIND_NOWILD; + wname = dns_fixedname_initname(&wfixed); +again: + have_wname = false; + /* + * We'll need some resources... + */ + dbuf = ns_client_getnamebuf(client); + if (dbuf == NULL) { + goto cleanup; + } + fname = ns_client_newname(client, dbuf, &b); + rdataset = ns_client_newrdataset(client); + sigrdataset = ns_client_newrdataset(client); + if (fname == NULL || rdataset == NULL || sigrdataset == NULL) { + goto cleanup; + } + + result = dns_db_findext(qctx->db, name, qctx->version, + dns_rdatatype_nsec, options, 0, &node, fname, + &cm, &ci, rdataset, sigrdataset); + if (node != NULL) { + dns_db_detachnode(qctx->db, &node); + } + + if (!dns_rdataset_isassociated(rdataset)) { + /* + * No NSEC proof available, return NSEC3 proofs instead. + */ + cname = dns_fixedname_initname(&cfixed); + /* + * Find the closest encloser. + */ + dns_name_copy(name, cname); + while (result == DNS_R_NXDOMAIN) { + labels = dns_name_countlabels(cname) - 1; + /* + * Sanity check. + */ + if (labels == 0U) { + goto cleanup; + } + dns_name_split(cname, labels, NULL, cname); + result = dns_db_findext(qctx->db, cname, qctx->version, + dns_rdatatype_nsec, options, 0, + NULL, fname, &cm, &ci, NULL, + NULL); + } + /* + * Add closest (provable) encloser NSEC3. + */ + query_findclosestnsec3(cname, qctx->db, qctx->version, client, + rdataset, sigrdataset, fname, true, + cname); + if (!dns_rdataset_isassociated(rdataset)) { + goto cleanup; + } + if (!ispositive) { + query_addrrset(qctx, &fname, &rdataset, &sigrdataset, + dbuf, DNS_SECTION_AUTHORITY); + } + + /* + * Replace resources which were consumed by query_addrrset. + */ + if (fname == NULL) { + dbuf = ns_client_getnamebuf(client); + if (dbuf == NULL) { + goto cleanup; + } + fname = ns_client_newname(client, dbuf, &b); + } + + if (rdataset == NULL) { + rdataset = ns_client_newrdataset(client); + } else if (dns_rdataset_isassociated(rdataset)) { + dns_rdataset_disassociate(rdataset); + } + + if (sigrdataset == NULL) { + sigrdataset = ns_client_newrdataset(client); + } else if (dns_rdataset_isassociated(sigrdataset)) { + dns_rdataset_disassociate(sigrdataset); + } + + if (fname == NULL || rdataset == NULL || sigrdataset == NULL) { + goto cleanup; + } + /* + * Add no qname proof. + */ + labels = dns_name_countlabels(cname) + 1; + if (dns_name_countlabels(name) == labels) { + dns_name_copy(name, wname); + } else { + dns_name_split(name, labels, NULL, wname); + } + + query_findclosestnsec3(wname, qctx->db, qctx->version, client, + rdataset, sigrdataset, fname, false, + NULL); + if (!dns_rdataset_isassociated(rdataset)) { + goto cleanup; + } + query_addrrset(qctx, &fname, &rdataset, &sigrdataset, dbuf, + DNS_SECTION_AUTHORITY); + + if (ispositive) { + goto cleanup; + } + + /* + * Replace resources which were consumed by query_addrrset. + */ + if (fname == NULL) { + dbuf = ns_client_getnamebuf(client); + if (dbuf == NULL) { + goto cleanup; + } + fname = ns_client_newname(client, dbuf, &b); + } + + if (rdataset == NULL) { + rdataset = ns_client_newrdataset(client); + } else if (dns_rdataset_isassociated(rdataset)) { + dns_rdataset_disassociate(rdataset); + } + + if (sigrdataset == NULL) { + sigrdataset = ns_client_newrdataset(client); + } else if (dns_rdataset_isassociated(sigrdataset)) { + dns_rdataset_disassociate(sigrdataset); + } + + if (fname == NULL || rdataset == NULL || sigrdataset == NULL) { + goto cleanup; + } + /* + * Add the no wildcard proof. + */ + result = dns_name_concatenate(dns_wildcardname, cname, wname, + NULL); + if (result != ISC_R_SUCCESS) { + goto cleanup; + } + + query_findclosestnsec3(wname, qctx->db, qctx->version, client, + rdataset, sigrdataset, fname, nodata, + NULL); + if (!dns_rdataset_isassociated(rdataset)) { + goto cleanup; + } + query_addrrset(qctx, &fname, &rdataset, &sigrdataset, dbuf, + DNS_SECTION_AUTHORITY); + + goto cleanup; + } else 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); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + (void)dns_name_fullcompare(name, fname, &order, + &olabels); + (void)dns_name_fullcompare(name, &nsec.next, &order, + &nlabels); + /* + * Check for a pathological condition created when + * serving some malformed signed zones and bail out. + */ + if (dns_name_countlabels(name) == nlabels) { + goto cleanup; + } + + 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 = true; + } + dns_rdata_freestruct(&nsec); + } + query_addrrset(qctx, &fname, &rdataset, &sigrdataset, dbuf, + DNS_SECTION_AUTHORITY); + } + if (rdataset != NULL) { + ns_client_putrdataset(client, &rdataset); + } + if (sigrdataset != NULL) { + ns_client_putrdataset(client, &sigrdataset); + } + if (fname != NULL) { + ns_client_releasename(client, &fname); + } + if (have_wname) { + ispositive = true; /* prevent loop */ + if (!dns_name_equal(name, wname)) { + name = wname; + goto again; + } + } +cleanup: + if (rdataset != NULL) { + ns_client_putrdataset(client, &rdataset); + } + if (sigrdataset != NULL) { + ns_client_putrdataset(client, &sigrdataset); + } + if (fname != NULL) { + ns_client_releasename(client, &fname); + } +} + +/*% + * Add NS records, and NSEC/NSEC3 wildcard proof records if needed, + * to the authority section. + */ +static void +query_addauth(query_ctx_t *qctx) { + CCTRACE(ISC_LOG_DEBUG(3), "query_addauth"); + /* + * Add NS records to the authority section (if we haven't already + * added them to the answer section). + */ + if (!qctx->want_restart && !NOAUTHORITY(qctx->client)) { + if (qctx->is_zone) { + if (!qctx->answer_has_ns) { + (void)query_addns(qctx); + } + } else if (!qctx->answer_has_ns && + qctx->qtype != dns_rdatatype_ns) + { + if (qctx->fname != NULL) { + ns_client_releasename(qctx->client, + &qctx->fname); + } + query_addbestns(qctx); + } + } + + /* + * Add NSEC records to the authority section if they're needed for + * DNSSEC wildcard proofs. + */ + if (qctx->need_wildcardproof && dns_db_issecure(qctx->db)) { + query_addwildcardproof(qctx, true, false); + } +} + +/* + * 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 +query_setup_sortlist(query_ctx_t *qctx) { + isc_netaddr_t netaddr; + ns_client_t *client = qctx->client; + dns_aclenv_t *env = client->manager->aclenv; + dns_acl_t *acl = NULL; + dns_aclelement_t *elt = NULL; + void *order_arg = NULL; + + isc_netaddr_fromsockaddr(&netaddr, &client->peeraddr); + switch (ns_sortlist_setup(client->view->sortlist, env, &netaddr, + &order_arg)) + { + case NS_SORTLISTTYPE_1ELEMENT: + elt = order_arg; + dns_message_setsortorder(client->message, + query_sortlist_order_1element, env, + NULL, elt); + break; + case NS_SORTLISTTYPE_2ELEMENT: + acl = order_arg; + dns_message_setsortorder(client->message, + query_sortlist_order_2element, env, + acl, NULL); + dns_acl_detach(&acl); + break; + case NS_SORTLISTTYPE_NONE: + break; + default: + UNREACHABLE(); + } +} + +/* + * When sending a referral, if the answer to the question is + * in the glue, sort it to the start of the additional section. + */ +static void +query_glueanswer(query_ctx_t *qctx) { + const dns_namelist_t *secs = qctx->client->message->sections; + const dns_section_t section = DNS_SECTION_ADDITIONAL; + dns_name_t *name; + dns_message_t *msg; + dns_rdataset_t *rdataset = NULL; + + if (!ISC_LIST_EMPTY(secs[DNS_SECTION_ANSWER]) || + qctx->client->message->rcode != dns_rcode_noerror || + (qctx->qtype != dns_rdatatype_a && + qctx->qtype != dns_rdatatype_aaaa)) + { + return; + } + + msg = qctx->client->message; + for (name = ISC_LIST_HEAD(msg->sections[section]); name != NULL; + name = ISC_LIST_NEXT(name, link)) + { + if (dns_name_equal(name, qctx->client->query.qname)) { + for (rdataset = ISC_LIST_HEAD(name->list); + rdataset != NULL; + rdataset = ISC_LIST_NEXT(rdataset, link)) + { + if (rdataset->type == qctx->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_REQUIRED; + } +} + +isc_result_t +ns_query_done(query_ctx_t *qctx) { + isc_result_t result = ISC_R_UNSET; + const dns_namelist_t *secs = qctx->client->message->sections; + bool nodetach; + + CCTRACE(ISC_LOG_DEBUG(3), "ns_query_done"); + + CALL_HOOK(NS_QUERY_DONE_BEGIN, qctx); + + /* + * General cleanup. + */ + qctx->rpz_st = qctx->client->query.rpz_st; + if (qctx->rpz_st != NULL && + (qctx->rpz_st->state & DNS_RPZ_RECURSING) == 0) + { + rpz_match_clear(qctx->rpz_st); + qctx->rpz_st->state &= ~DNS_RPZ_DONE_QNAME; + } + + qctx_clean(qctx); + qctx_freedata(qctx); + + if (qctx->client->query.gluedb != NULL) { + dns_db_detach(&qctx->client->query.gluedb); + } + + /* + * Clear the AA bit if we're not authoritative. + */ + if (qctx->client->query.restarts == 0 && !qctx->authoritative) { + qctx->client->message->flags &= ~DNS_MESSAGEFLAG_AA; + } + + /* + * Do we need to restart the query (e.g. for CNAME chaining)? + */ + if (qctx->want_restart && qctx->client->query.restarts < MAX_RESTARTS) { + qctx->client->query.restarts++; + return (ns__query_start(qctx)); + } + + if (qctx->result != ISC_R_SUCCESS && + (!PARTIALANSWER(qctx->client) || WANTRECURSION(qctx->client) || + qctx->result == DNS_R_DROP)) + { + if (qctx->result == DNS_R_DUPLICATE || + qctx->result == DNS_R_DROP) + { + /* + * This was a duplicate query that we are + * recursing on or the result of rate limiting. + * Don't send a response now for a duplicate query, + * because the original will still cause a response. + */ + query_next(qctx->client, qctx->result); + } else { + /* + * 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. + */ + INSIST(qctx->line >= 0); + query_error(qctx->client, qctx->result, qctx->line); + } + + qctx->detach_client = true; + return (qctx->result); + } + + /* + * If we're recursing then just return; the query will + * resume when recursion ends. + */ + if (RECURSING(qctx->client) && + (!QUERY_STALETIMEOUT(&qctx->client->query) || + ((qctx->options & DNS_GETDB_STALEFIRST) != 0))) + { + return (qctx->result); + } + + /* + * We are done. Set up sortlist data for the message + * rendering code, sort the answer to the front of the + * additional section if necessary, make a final tweak + * to the AA bit if the auth-nxdomain config option + * says so, then render and send the response. + */ + query_setup_sortlist(qctx); + query_glueanswer(qctx); + + if (qctx->client->message->rcode == dns_rcode_nxdomain && + qctx->view->auth_nxdomain) + { + qctx->client->message->flags |= DNS_MESSAGEFLAG_AA; + } + + /* + * If the response is somehow unexpected for the client and this + * is a result of recursion, return an error to the caller + * to indicate it may need to be logged. + */ + if (qctx->resuming && + (ISC_LIST_EMPTY(secs[DNS_SECTION_ANSWER]) || + qctx->client->message->rcode != dns_rcode_noerror)) + { + qctx->result = ISC_R_FAILURE; + } + + CALL_HOOK(NS_QUERY_DONE_SEND, qctx); + + /* + * Client may have been detached after query_send(), so + * we test and store the flag state here, for safety. + */ + nodetach = qctx->client->nodetach; + query_send(qctx->client); + + if (qctx->refresh_rrset) { + /* + * If we reached this point then it means that we have found a + * stale RRset entry in cache and BIND is configured to allow + * queries to be answered with stale data if no active RRset + * is available, i.e. "stale-anwer-client-timeout 0". But, we + * still need to refresh the RRset. To prevent adding duplicate + * RRsets, clear the RRsets from the message before doing the + * refresh. + */ + message_clearrdataset(qctx->client->message, 0); + query_refresh_rrset(qctx); + } + + if (!nodetach) { + qctx->detach_client = true; + } + return (qctx->result); + +cleanup: + return (result); +} + +static void +log_tat(ns_client_t *client) { + char namebuf[DNS_NAME_FORMATSIZE]; + char clientbuf[ISC_NETADDR_FORMATSIZE]; + char classbuf[DNS_RDATACLASS_FORMATSIZE]; + isc_netaddr_t netaddr; + char *tags = NULL; + size_t taglen = 0; + + if (!isc_log_wouldlog(ns_lctx, ISC_LOG_INFO)) { + return; + } + + if ((client->query.qtype != dns_rdatatype_null || + !dns_name_istat(client->query.qname)) && + (client->keytag == NULL || + client->query.qtype != dns_rdatatype_dnskey)) + { + return; + } + + isc_netaddr_fromsockaddr(&netaddr, &client->peeraddr); + dns_name_format(client->query.qname, namebuf, sizeof(namebuf)); + isc_netaddr_format(&netaddr, clientbuf, sizeof(clientbuf)); + dns_rdataclass_format(client->view->rdclass, classbuf, + sizeof(classbuf)); + + if (client->query.qtype == dns_rdatatype_dnskey) { + uint16_t keytags = client->keytag_len / 2; + size_t len = taglen = sizeof("65000") * keytags + 1; + char *cp = tags = isc_mem_get(client->mctx, taglen); + int i = 0; + + INSIST(client->keytag != NULL); + if (tags != NULL) { + while (keytags-- > 0U) { + int n; + uint16_t keytag; + keytag = (client->keytag[i * 2] << 8) | + client->keytag[i * 2 + 1]; + n = snprintf(cp, len, " %u", keytag); + if (n > 0 && (size_t)n <= len) { + cp += n; + len -= n; + i++; + } else { + break; + } + } + } + } + + isc_log_write(ns_lctx, NS_LOGCATEGORY_TAT, NS_LOGMODULE_QUERY, + ISC_LOG_INFO, "trust-anchor-telemetry '%s/%s' from %s%s", + namebuf, classbuf, clientbuf, tags != NULL ? tags : ""); + if (tags != NULL) { + isc_mem_put(client->mctx, tags, taglen); + } +} + +static void +log_query(ns_client_t *client, unsigned int flags, unsigned int extflags) { + char namebuf[DNS_NAME_FORMATSIZE]; + char typebuf[DNS_RDATATYPE_FORMATSIZE]; + char classbuf[DNS_RDATACLASS_FORMATSIZE]; + char onbuf[ISC_NETADDR_FORMATSIZE]; + char ecsbuf[DNS_ECS_FORMATSIZE + sizeof(" [ECS ]") - 1] = { 0 }; + char ednsbuf[sizeof("E(65535)")] = { 0 }; + dns_rdataset_t *rdataset; + int level = ISC_LOG_INFO; + + if (!isc_log_wouldlog(ns_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, classbuf, sizeof(classbuf)); + dns_rdatatype_format(rdataset->type, typebuf, sizeof(typebuf)); + isc_netaddr_format(&client->destaddr, onbuf, sizeof(onbuf)); + + if (client->ednsversion >= 0) { + snprintf(ednsbuf, sizeof(ednsbuf), "E(%hd)", + client->ednsversion); + } + + if (HAVEECS(client)) { + strlcpy(ecsbuf, " [ECS ", sizeof(ecsbuf)); + dns_ecs_format(&client->ecs, ecsbuf + 6, sizeof(ecsbuf) - 6); + strlcat(ecsbuf, "]", sizeof(ecsbuf)); + } + + ns_client_log(client, NS_LOGCATEGORY_QUERIES, NS_LOGMODULE_QUERY, level, + "query: %s %s %s %s%s%s%s%s%s%s (%s)%s", namebuf, + classbuf, typebuf, WANTRECURSION(client) ? "+" : "-", + (client->signer != NULL) ? "S" : "", ednsbuf, + TCP(client) ? "T" : "", + ((extflags & DNS_MESSAGEEXTFLAG_DO) != 0) ? "D" : "", + ((flags & DNS_MESSAGEFLAG_CD) != 0) ? "C" : "", + HAVECOOKIE(client) ? "V" + : WANTCOOKIE(client) ? "K" + : "", + onbuf, ecsbuf); +} + +static void +log_queryerror(ns_client_t *client, isc_result_t result, int line, int level) { + char namebuf[DNS_NAME_FORMATSIZE]; + char typebuf[DNS_RDATATYPE_FORMATSIZE]; + char classbuf[DNS_RDATACLASS_FORMATSIZE]; + const char *namep, *typep, *classp, *sep1, *sep2; + dns_rdataset_t *rdataset; + + if (!isc_log_wouldlog(ns_lctx, level)) { + return; + } + + namep = typep = classp = sep1 = sep2 = ""; + + /* + * Query errors can happen for various reasons. In some cases we cannot + * even assume the query contains a valid question section, so we should + * expect exceptional cases. + */ + if (client->query.origqname != NULL) { + dns_name_format(client->query.origqname, namebuf, + sizeof(namebuf)); + namep = namebuf; + sep1 = " for "; + + rdataset = ISC_LIST_HEAD(client->query.origqname->list); + if (rdataset != NULL) { + dns_rdataclass_format(rdataset->rdclass, classbuf, + sizeof(classbuf)); + classp = classbuf; + dns_rdatatype_format(rdataset->type, typebuf, + sizeof(typebuf)); + typep = typebuf; + sep2 = "/"; + } + } + + ns_client_log(client, NS_LOGCATEGORY_QUERY_ERRORS, NS_LOGMODULE_QUERY, + level, "query failed (%s)%s%s%s%s%s%s at %s:%d", + isc_result_totext(result), sep1, namep, sep2, classp, + sep2, typep, __FILE__, line); +} + +void +ns_query_start(ns_client_t *client, isc_nmhandle_t *handle) { + isc_result_t result; + dns_message_t *message; + dns_rdataset_t *rdataset; + dns_rdatatype_t qtype; + unsigned int saved_extflags; + unsigned int saved_flags; + + REQUIRE(NS_CLIENT_VALID(client)); + + /* + * Attach to the request handle + */ + isc_nmhandle_attach(handle, &client->reqhandle); + + message = client->message; + saved_extflags = client->extflags; + saved_flags = client->message->flags; + + CTRACE(ISC_LOG_DEBUG(3), "ns_query_start"); + + /* + * Ensure that appropriate cleanups occur. + */ + client->cleanup = query_cleanup; + + 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; + } + + switch (client->view->minimalresponses) { + case dns_minimal_no: + break; + case dns_minimal_yes: + client->query.attributes |= (NS_QUERYATTR_NOAUTHORITY | + NS_QUERYATTR_NOADDITIONAL); + break; + case dns_minimal_noauth: + client->query.attributes |= NS_QUERYATTR_NOAUTHORITY; + break; + case dns_minimal_noauthrec: + if ((message->flags & DNS_MESSAGEFLAG_RD) != 0) { + client->query.attributes |= NS_QUERYATTR_NOAUTHORITY; + } + break; + } + + if (client->view->cachedb == NULL || !client->view->recursion) { + /* + * We don't have a cache. Turn off cache support and + * recursion. + */ + client->query.attributes &= ~(NS_QUERYATTR_RECURSIONOK | + NS_QUERYATTR_CACHEOK); + client->attributes |= NS_CLIENTATTR_NOSETFC; + } 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; + client->attributes |= NS_CLIENTATTR_NOSETFC; + } + + /* + * Check for multiple question queries, since edns1 is dead. + */ + if (message->counts[DNS_SECTION_QUESTION] > 1) { + query_error(client, DNS_R_FORMERR, __LINE__); + return; + } + + /* + * Get the question name. + */ + result = dns_message_firstname(message, DNS_SECTION_QUESTION); + if (result != ISC_R_SUCCESS) { + query_error(client, result, __LINE__); + 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, __LINE__); + } else { + query_error(client, result, __LINE__); + } + return; + } + + if ((client->sctx->options & NS_SERVER_LOGQUERIES) != 0) { + log_query(client, saved_flags, saved_extflags); + } + + /* + * Check for meta-queries like IXFR and AXFR. + */ + rdataset = ISC_LIST_HEAD(client->query.qname->list); + INSIST(rdataset != NULL); + client->query.qtype = qtype = rdataset->type; + dns_rdatatypestats_increment(client->sctx->rcvquerystats, qtype); + + log_tat(client); + + if (dns_rdatatype_ismeta(qtype)) { + switch (qtype) { + case dns_rdatatype_any: + break; /* Let the query logic handle it. */ + case dns_rdatatype_ixfr: + case dns_rdatatype_axfr: + if (isc_nm_is_http_handle(handle)) { + /* + * We cannot use DoH for zone transfers. + * According to RFC 8484 a DoH request contains + * exactly one DNS message (see Section 6: + * Definition of the "application/dns-message" + * Media Type). + * + * This makes DoH unsuitable for zone transfers + * as often (and usually!) these need more than + * one DNS message, especially for larger zones. + * As zone transfers over DoH are not (yet) + * standardised, nor discussed in RFC 8484, + * the best thing we can do is to return "not + * implemented". + */ + query_error(client, DNS_R_NOTIMP, __LINE__); + return; + } + if (isc_nm_socket_type(handle) == isc_nm_tlsdnssocket) { + /* + * Currently this code is here for DoT, which + * has more complex requirements for zone + * transfers compared to other stream + * protocols. See RFC 9103 for details. + */ + switch (isc_nm_xfr_checkperm(handle)) { + case ISC_R_SUCCESS: + break; + case ISC_R_DOTALPNERROR: + query_error(client, DNS_R_NOALPN, + __LINE__); + return; + default: + query_error(client, DNS_R_REFUSED, + __LINE__); + return; + } + } + ns_xfr_start(client, rdataset->type); + return; + case dns_rdatatype_maila: + case dns_rdatatype_mailb: + query_error(client, DNS_R_NOTIMP, __LINE__); + return; + case dns_rdatatype_tkey: + result = dns_tkey_processquery( + client->message, client->sctx->tkeyctx, + client->view->dynamickeys); + if (result == ISC_R_SUCCESS) { + query_send(client); + } else { + query_error(client, result, __LINE__); + } + return; + default: /* TSIG, etc. */ + query_error(client, DNS_R_FORMERR, __LINE__); + return; + } + } + + /* + * Turn on minimal response for (C)DNSKEY and (C)DS queries. + */ + if (qtype == dns_rdatatype_dnskey || qtype == dns_rdatatype_ds || + qtype == dns_rdatatype_cdnskey || qtype == dns_rdatatype_cds) + { + client->query.attributes |= (NS_QUERYATTR_NOAUTHORITY | + NS_QUERYATTR_NOADDITIONAL); + } else if (qtype == dns_rdatatype_ns) { + /* + * Always turn on additional records for NS queries. + */ + client->query.attributes &= ~(NS_QUERYATTR_NOAUTHORITY | + NS_QUERYATTR_NOADDITIONAL); + } + + /* + * Maybe turn on minimal responses for ANY queries. + */ + if (qtype == dns_rdatatype_any && client->view->minimal_any && + !TCP(client)) + { + client->query.attributes |= (NS_QUERYATTR_NOAUTHORITY | + NS_QUERYATTR_NOADDITIONAL); + } + + /* + * Turn on minimal responses for EDNS/UDP bufsize 512 queries. + */ + if (client->ednsversion >= 0 && client->udpsize <= 512U && !TCP(client)) + { + client->query.attributes |= (NS_QUERYATTR_NOAUTHORITY | + NS_QUERYATTR_NOADDITIONAL); + } + + /* + * 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. + * + * We don't need to set DNS_DBFIND_PENDINGOK when validation is + * disabled as there will be no pending data. + */ + if ((message->flags & DNS_MESSAGEFLAG_CD) != 0 || + qtype == dns_rdatatype_rrsig) + { + client->query.dboptions |= DNS_DBFIND_PENDINGOK; + client->query.fetchoptions |= DNS_FETCHOPT_NOVALIDATE; + } else if (!client->view->enablevalidation) { + client->query.fetchoptions |= DNS_FETCHOPT_NOVALIDATE; + } + + if (client->view->qminimization) { + client->query.fetchoptions |= DNS_FETCHOPT_QMINIMIZE | + DNS_FETCHOPT_QMIN_SKIP_IP6A; + if (client->view->qmin_strict) { + client->query.fetchoptions |= DNS_FETCHOPT_QMIN_STRICT; + } + } + + /* + * Allow glue NS records to be added to the authority section + * if the answer is secure. + */ + if ((message->flags & DNS_MESSAGEFLAG_CD) != 0) { + client->query.attributes &= ~NS_QUERYATTR_SECURE; + } + + /* + * Set NS_CLIENTATTR_WANTAD if the client has set AD in the query. + * This allows AD to be returned on queries without DO set. + */ + if ((message->flags & DNS_MESSAGEFLAG_AD) != 0) { + client->attributes |= NS_CLIENTATTR_WANTAD; + } + + /* + * This is an ordinary query. + */ + result = dns_message_reply(message, true); + if (result != ISC_R_SUCCESS) { + query_next(client, result); + return; + } + + /* + * Assume authoritative response until it is known to be + * otherwise. + * + * If "-T noaa" has been set on the command line don't set + * AA on authoritative answers. + */ + if ((client->sctx->options & NS_SERVER_NOAA) == 0) { + message->flags |= DNS_MESSAGEFLAG_AA; + } + + /* + * Set AD. We must clear it if we add non-validated data to a + * response. + */ + if (WANTDNSSEC(client) || WANTAD(client)) { + message->flags |= DNS_MESSAGEFLAG_AD; + } + + (void)query_setup(client, qtype); +} |