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authorTom Rhodes <trhodes@FreeBSD.org>2004-09-19 01:30:24 +0000
committerTom Rhodes <trhodes@FreeBSD.org>2004-09-19 01:30:24 +0000
commitb1e4bd53e00e9694dd378a884abd3f2dd790190d (patch)
tree97706b7f62557da0a2539b026e5cf66008ddf8c6 /contrib/bind9/lib/dns/resolver.c
downloadsrc-b1e4bd53e00e9694dd378a884abd3f2dd790190d.tar.gz
src-b1e4bd53e00e9694dd378a884abd3f2dd790190d.zip
Vender import of BIND 9.3.0rc4.
Notes
Notes: svn path=/vendor/bind9/dist/; revision=135446
Diffstat (limited to 'contrib/bind9/lib/dns/resolver.c')
-rw-r--r--contrib/bind9/lib/dns/resolver.c6473
1 files changed, 6473 insertions, 0 deletions
diff --git a/contrib/bind9/lib/dns/resolver.c b/contrib/bind9/lib/dns/resolver.c
new file mode 100644
index 000000000000..c76631a2bbf1
--- /dev/null
+++ b/contrib/bind9/lib/dns/resolver.c
@@ -0,0 +1,6473 @@
+/*
+ * Copyright (C) 2004 Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) 1999-2003 Internet Software Consortium.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
+ * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
+ * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+ * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+ * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/* $Id: resolver.c,v 1.218.2.18.4.43 2004/08/28 06:25:19 marka Exp $ */
+
+#include <config.h>
+
+#include <isc/print.h>
+#include <isc/string.h>
+#include <isc/task.h>
+#include <isc/timer.h>
+#include <isc/util.h>
+
+#include <dns/acl.h>
+#include <dns/adb.h>
+#include <dns/db.h>
+#include <dns/dispatch.h>
+#include <dns/events.h>
+#include <dns/forward.h>
+#include <dns/keytable.h>
+#include <dns/log.h>
+#include <dns/message.h>
+#include <dns/ncache.h>
+#include <dns/opcode.h>
+#include <dns/peer.h>
+#include <dns/rbt.h>
+#include <dns/rcode.h>
+#include <dns/rdata.h>
+#include <dns/rdataclass.h>
+#include <dns/rdatalist.h>
+#include <dns/rdataset.h>
+#include <dns/rdatastruct.h>
+#include <dns/rdatatype.h>
+#include <dns/resolver.h>
+#include <dns/result.h>
+#include <dns/tsig.h>
+#include <dns/validator.h>
+
+#define DNS_RESOLVER_TRACE
+#ifdef DNS_RESOLVER_TRACE
+#define RTRACE(m) isc_log_write(dns_lctx, \
+ DNS_LOGCATEGORY_RESOLVER, \
+ DNS_LOGMODULE_RESOLVER, \
+ ISC_LOG_DEBUG(3), \
+ "res %p: %s", res, (m))
+#define RRTRACE(r, m) isc_log_write(dns_lctx, \
+ DNS_LOGCATEGORY_RESOLVER, \
+ DNS_LOGMODULE_RESOLVER, \
+ ISC_LOG_DEBUG(3), \
+ "res %p: %s", (r), (m))
+#define FCTXTRACE(m) isc_log_write(dns_lctx, \
+ DNS_LOGCATEGORY_RESOLVER, \
+ DNS_LOGMODULE_RESOLVER, \
+ ISC_LOG_DEBUG(3), \
+ "fctx %p(%s'): %s", fctx, fctx->info, (m))
+#define FCTXTRACE2(m1, m2) \
+ isc_log_write(dns_lctx, \
+ DNS_LOGCATEGORY_RESOLVER, \
+ DNS_LOGMODULE_RESOLVER, \
+ ISC_LOG_DEBUG(3), \
+ "fctx %p(%s): %s %s", \
+ fctx, fctx->info, (m1), (m2))
+#define FTRACE(m) isc_log_write(dns_lctx, \
+ DNS_LOGCATEGORY_RESOLVER, \
+ DNS_LOGMODULE_RESOLVER, \
+ ISC_LOG_DEBUG(3), \
+ "fetch %p (fctx %p(%s)): %s", \
+ fetch, fetch->private, \
+ fetch->private->info, (m))
+#define QTRACE(m) isc_log_write(dns_lctx, \
+ DNS_LOGCATEGORY_RESOLVER, \
+ DNS_LOGMODULE_RESOLVER, \
+ ISC_LOG_DEBUG(3), \
+ "resquery %p (fctx %p(%s)): %s", \
+ query, query->fctx, \
+ query->fctx->info, (m))
+#else
+#define RTRACE(m)
+#define RRTRACE(r, m)
+#define FCTXTRACE(m)
+#define FTRACE(m)
+#define QTRACE(m)
+#endif
+
+/*
+ * Maximum EDNS0 input packet size.
+ */
+#define RECV_BUFFER_SIZE 4096 /* XXXRTH Constant. */
+
+/*
+ * This defines the maximum number of timeouts we will permit before we
+ * disable EDNS0 on the query.
+ */
+#define MAX_EDNS0_TIMEOUTS 3
+
+typedef struct fetchctx fetchctx_t;
+
+typedef struct query {
+ /* Locked by task event serialization. */
+ unsigned int magic;
+ fetchctx_t * fctx;
+ isc_mem_t * mctx;
+ dns_dispatchmgr_t * dispatchmgr;
+ dns_dispatch_t * dispatch;
+ dns_adbaddrinfo_t * addrinfo;
+ isc_socket_t * tcpsocket;
+ isc_time_t start;
+ dns_messageid_t id;
+ dns_dispentry_t * dispentry;
+ ISC_LINK(struct query) link;
+ isc_buffer_t buffer;
+ isc_buffer_t *tsig;
+ dns_tsigkey_t *tsigkey;
+ unsigned int options;
+ unsigned int attributes;
+ unsigned int sends;
+ unsigned int connects;
+ unsigned char data[512];
+} resquery_t;
+
+#define QUERY_MAGIC ISC_MAGIC('Q', '!', '!', '!')
+#define VALID_QUERY(query) ISC_MAGIC_VALID(query, QUERY_MAGIC)
+
+#define RESQUERY_ATTR_CANCELED 0x02
+
+#define RESQUERY_CONNECTING(q) ((q)->connects > 0)
+#define RESQUERY_CANCELED(q) (((q)->attributes & \
+ RESQUERY_ATTR_CANCELED) != 0)
+#define RESQUERY_SENDING(q) ((q)->sends > 0)
+
+typedef enum {
+ fetchstate_init = 0, /* Start event has not run yet. */
+ fetchstate_active,
+ fetchstate_done /* FETCHDONE events posted. */
+} fetchstate;
+
+struct fetchctx {
+ /* Not locked. */
+ unsigned int magic;
+ dns_resolver_t * res;
+ dns_name_t name;
+ dns_rdatatype_t type;
+ unsigned int options;
+ unsigned int bucketnum;
+ char * info;
+ /* Locked by appropriate bucket lock. */
+ fetchstate state;
+ isc_boolean_t want_shutdown;
+ isc_boolean_t cloned;
+ unsigned int references;
+ isc_event_t control_event;
+ ISC_LINK(struct fetchctx) link;
+ ISC_LIST(dns_fetchevent_t) events;
+ /* Locked by task event serialization. */
+ dns_name_t domain;
+ dns_rdataset_t nameservers;
+ unsigned int attributes;
+ isc_timer_t * timer;
+ isc_time_t expires;
+ isc_interval_t interval;
+ dns_message_t * qmessage;
+ dns_message_t * rmessage;
+ ISC_LIST(resquery_t) queries;
+ dns_adbfindlist_t finds;
+ dns_adbfind_t * find;
+ dns_adbfindlist_t altfinds;
+ dns_adbfind_t * altfind;
+ dns_adbaddrinfolist_t forwaddrs;
+ dns_adbaddrinfolist_t altaddrs;
+ isc_sockaddrlist_t forwarders;
+ dns_fwdpolicy_t fwdpolicy;
+ isc_sockaddrlist_t bad;
+ ISC_LIST(dns_validator_t) validators;
+ dns_db_t * cache;
+ dns_adb_t * adb;
+
+ /*
+ * The number of events we're waiting for.
+ */
+ unsigned int pending;
+
+ /*
+ * The number of times we've "restarted" the current
+ * nameserver set. This acts as a failsafe to prevent
+ * us from pounding constantly on a particular set of
+ * servers that, for whatever reason, are not giving
+ * us useful responses, but are responding in such a
+ * way that they are not marked "bad".
+ */
+ unsigned int restarts;
+
+ /*
+ * The number of timeouts that have occurred since we
+ * last successfully received a response packet. This
+ * is used for EDNS0 black hole detection.
+ */
+ unsigned int timeouts;
+ /*
+ * Look aside state for DS lookups.
+ */
+ dns_name_t nsname;
+ dns_fetch_t * nsfetch;
+ dns_rdataset_t nsrrset;
+};
+
+#define FCTX_MAGIC ISC_MAGIC('F', '!', '!', '!')
+#define VALID_FCTX(fctx) ISC_MAGIC_VALID(fctx, FCTX_MAGIC)
+
+#define FCTX_ATTR_HAVEANSWER 0x0001
+#define FCTX_ATTR_GLUING 0x0002
+#define FCTX_ATTR_ADDRWAIT 0x0004
+#define FCTX_ATTR_SHUTTINGDOWN 0x0008
+#define FCTX_ATTR_WANTCACHE 0x0010
+#define FCTX_ATTR_WANTNCACHE 0x0020
+#define FCTX_ATTR_NEEDEDNS0 0x0040
+#define FCTX_ATTR_TRIEDFIND 0x0080
+#define FCTX_ATTR_TRIEDALT 0x0100
+
+#define HAVE_ANSWER(f) (((f)->attributes & FCTX_ATTR_HAVEANSWER) != \
+ 0)
+#define GLUING(f) (((f)->attributes & FCTX_ATTR_GLUING) != \
+ 0)
+#define ADDRWAIT(f) (((f)->attributes & FCTX_ATTR_ADDRWAIT) != \
+ 0)
+#define SHUTTINGDOWN(f) (((f)->attributes & FCTX_ATTR_SHUTTINGDOWN) \
+ != 0)
+#define WANTCACHE(f) (((f)->attributes & FCTX_ATTR_WANTCACHE) != 0)
+#define WANTNCACHE(f) (((f)->attributes & FCTX_ATTR_WANTNCACHE) != 0)
+#define NEEDEDNS0(f) (((f)->attributes & FCTX_ATTR_NEEDEDNS0) != 0)
+#define TRIEDFIND(f) (((f)->attributes & FCTX_ATTR_TRIEDFIND) != 0)
+#define TRIEDALT(f) (((f)->attributes & FCTX_ATTR_TRIEDALT) != 0)
+
+struct dns_fetch {
+ unsigned int magic;
+ fetchctx_t * private;
+};
+
+#define DNS_FETCH_MAGIC ISC_MAGIC('F', 't', 'c', 'h')
+#define DNS_FETCH_VALID(fetch) ISC_MAGIC_VALID(fetch, DNS_FETCH_MAGIC)
+
+typedef struct fctxbucket {
+ isc_task_t * task;
+ isc_mutex_t lock;
+ ISC_LIST(fetchctx_t) fctxs;
+ isc_boolean_t exiting;
+} fctxbucket_t;
+
+typedef struct alternate {
+ isc_boolean_t isaddress;
+ union {
+ isc_sockaddr_t addr;
+ struct {
+ dns_name_t name;
+ in_port_t port;
+ } _n;
+ } _u;
+ ISC_LINK(struct alternate) link;
+} alternate_t;
+
+struct dns_resolver {
+ /* Unlocked. */
+ unsigned int magic;
+ isc_mem_t * mctx;
+ isc_mutex_t lock;
+ isc_mutex_t nlock;
+ isc_mutex_t primelock;
+ dns_rdataclass_t rdclass;
+ isc_socketmgr_t * socketmgr;
+ isc_timermgr_t * timermgr;
+ isc_taskmgr_t * taskmgr;
+ dns_view_t * view;
+ isc_boolean_t frozen;
+ unsigned int options;
+ dns_dispatchmgr_t * dispatchmgr;
+ dns_dispatch_t * dispatchv4;
+ dns_dispatch_t * dispatchv6;
+ unsigned int nbuckets;
+ fctxbucket_t * buckets;
+ isc_uint32_t lame_ttl;
+ ISC_LIST(alternate_t) alternates;
+ isc_uint16_t udpsize;
+#if USE_ALGLOCK
+ isc_rwlock_t alglock;
+#endif
+ dns_rbt_t * algorithms;
+#if USE_MBSLOCK
+ isc_rwlock_t mbslock;
+#endif
+ dns_rbt_t * mustbesecure;
+ /* Locked by lock. */
+ unsigned int references;
+ isc_boolean_t exiting;
+ isc_eventlist_t whenshutdown;
+ unsigned int activebuckets;
+ isc_boolean_t priming;
+ /* Locked by primelock. */
+ dns_fetch_t * primefetch;
+ /* Locked by nlock. */
+ unsigned int nfctx;
+};
+
+#define RES_MAGIC ISC_MAGIC('R', 'e', 's', '!')
+#define VALID_RESOLVER(res) ISC_MAGIC_VALID(res, RES_MAGIC)
+
+/*
+ * Private addrinfo flags. These must not conflict with DNS_FETCHOPT_NOEDNS0,
+ * which we also use as an addrinfo flag.
+ */
+#define FCTX_ADDRINFO_MARK 0x0001
+#define FCTX_ADDRINFO_FORWARDER 0x1000
+#define UNMARKED(a) (((a)->flags & FCTX_ADDRINFO_MARK) \
+ == 0)
+#define ISFORWARDER(a) (((a)->flags & \
+ FCTX_ADDRINFO_FORWARDER) != 0)
+
+#define NXDOMAIN(r) (((r)->attributes & DNS_RDATASETATTR_NXDOMAIN) != 0)
+
+static void destroy(dns_resolver_t *res);
+static void empty_bucket(dns_resolver_t *res);
+static isc_result_t resquery_send(resquery_t *query);
+static void resquery_response(isc_task_t *task, isc_event_t *event);
+static void resquery_connected(isc_task_t *task, isc_event_t *event);
+static void fctx_try(fetchctx_t *fctx);
+static isc_boolean_t fctx_destroy(fetchctx_t *fctx);
+static isc_result_t ncache_adderesult(dns_message_t *message,
+ dns_db_t *cache, dns_dbnode_t *node,
+ dns_rdatatype_t covers,
+ isc_stdtime_t now, dns_ttl_t maxttl,
+ dns_rdataset_t *ardataset,
+ isc_result_t *eresultp);
+
+static isc_boolean_t
+fix_mustbedelegationornxdomain(dns_message_t *message, fetchctx_t *fctx) {
+ dns_name_t *name;
+ dns_name_t *domain = &fctx->domain;
+ dns_rdataset_t *rdataset;
+ dns_rdatatype_t type;
+ isc_result_t result;
+ isc_boolean_t keep_auth = ISC_FALSE;
+
+ if (message->rcode == dns_rcode_nxdomain)
+ return (ISC_FALSE);
+
+ /*
+ * Look for BIND 8 style delegations.
+ * Also look for answers to ANY queries where the duplicate NS RRset
+ * may have been stripped from the authority section.
+ */
+ if (message->counts[DNS_SECTION_ANSWER] != 0 &&
+ (fctx->type == dns_rdatatype_ns ||
+ fctx->type == dns_rdatatype_any)) {
+ result = dns_message_firstname(message, DNS_SECTION_ANSWER);
+ while (result == ISC_R_SUCCESS) {
+ name = NULL;
+ dns_message_currentname(message, DNS_SECTION_ANSWER,
+ &name);
+ for (rdataset = ISC_LIST_HEAD(name->list);
+ rdataset != NULL;
+ rdataset = ISC_LIST_NEXT(rdataset, link)) {
+ type = rdataset->type;
+ if (type != dns_rdatatype_ns)
+ continue;
+ if (dns_name_issubdomain(name, domain))
+ return (ISC_FALSE);
+ }
+ result = dns_message_nextname(message,
+ DNS_SECTION_ANSWER);
+ }
+ }
+
+ /* Look for referral. */
+ if (message->counts[DNS_SECTION_AUTHORITY] == 0)
+ goto munge;
+
+ result = dns_message_firstname(message, DNS_SECTION_AUTHORITY);
+ while (result == ISC_R_SUCCESS) {
+ name = NULL;
+ dns_message_currentname(message, DNS_SECTION_AUTHORITY, &name);
+ for (rdataset = ISC_LIST_HEAD(name->list);
+ rdataset != NULL;
+ rdataset = ISC_LIST_NEXT(rdataset, link)) {
+ type = rdataset->type;
+ if (type == dns_rdatatype_soa &&
+ dns_name_equal(name, domain))
+ keep_auth = ISC_TRUE;
+ if (type != dns_rdatatype_ns &&
+ type != dns_rdatatype_soa)
+ continue;
+ if (dns_name_equal(name, domain))
+ goto munge;
+ if (dns_name_issubdomain(name, domain))
+ return (ISC_FALSE);
+ }
+ result = dns_message_nextname(message, DNS_SECTION_AUTHORITY);
+ }
+
+ munge:
+ message->rcode = dns_rcode_nxdomain;
+ message->counts[DNS_SECTION_ANSWER] = 0;
+ if (!keep_auth)
+ message->counts[DNS_SECTION_AUTHORITY] = 0;
+ message->counts[DNS_SECTION_ADDITIONAL] = 0;
+ return (ISC_TRUE);
+}
+
+static inline isc_result_t
+fctx_starttimer(fetchctx_t *fctx) {
+ /*
+ * Start the lifetime timer for fctx.
+ *
+ * This is also used for stopping the idle timer; in that
+ * case we must purge events already posted to ensure that
+ * no further idle events are delivered.
+ */
+ return (isc_timer_reset(fctx->timer, isc_timertype_once,
+ &fctx->expires, NULL,
+ ISC_TRUE));
+}
+
+static inline void
+fctx_stoptimer(fetchctx_t *fctx) {
+ isc_result_t result;
+
+ /*
+ * We don't return a result if resetting the timer to inactive fails
+ * since there's nothing to be done about it. Resetting to inactive
+ * should never fail anyway, since the code as currently written
+ * cannot fail in that case.
+ */
+ result = isc_timer_reset(fctx->timer, isc_timertype_inactive,
+ NULL, NULL, ISC_TRUE);
+ if (result != ISC_R_SUCCESS) {
+ UNEXPECTED_ERROR(__FILE__, __LINE__,
+ "isc_timer_reset(): %s",
+ isc_result_totext(result));
+ }
+}
+
+
+static inline isc_result_t
+fctx_startidletimer(fetchctx_t *fctx) {
+ /*
+ * Start the idle timer for fctx. The lifetime timer continues
+ * to be in effect.
+ */
+ return (isc_timer_reset(fctx->timer, isc_timertype_once,
+ &fctx->expires, &fctx->interval,
+ ISC_FALSE));
+}
+
+/*
+ * Stopping the idle timer is equivalent to calling fctx_starttimer(), but
+ * we use fctx_stopidletimer for readability in the code below.
+ */
+#define fctx_stopidletimer fctx_starttimer
+
+
+static inline void
+resquery_destroy(resquery_t **queryp) {
+ resquery_t *query;
+
+ REQUIRE(queryp != NULL);
+ query = *queryp;
+ REQUIRE(!ISC_LINK_LINKED(query, link));
+
+ INSIST(query->tcpsocket == NULL);
+
+ query->magic = 0;
+ isc_mem_put(query->mctx, query, sizeof(*query));
+ *queryp = NULL;
+}
+
+static void
+fctx_cancelquery(resquery_t **queryp, dns_dispatchevent_t **deventp,
+ isc_time_t *finish, isc_boolean_t no_response)
+{
+ fetchctx_t *fctx;
+ resquery_t *query;
+ unsigned int rtt;
+ unsigned int factor;
+ dns_adbfind_t *find;
+ dns_adbaddrinfo_t *addrinfo;
+
+ query = *queryp;
+ fctx = query->fctx;
+
+ FCTXTRACE("cancelquery");
+
+ REQUIRE(!RESQUERY_CANCELED(query));
+
+ query->attributes |= RESQUERY_ATTR_CANCELED;
+
+ /*
+ * Should we update the RTT?
+ */
+ if (finish != NULL || no_response) {
+ if (finish != NULL) {
+ /*
+ * We have both the start and finish times for this
+ * packet, so we can compute a real RTT.
+ */
+ rtt = (unsigned int)isc_time_microdiff(finish,
+ &query->start);
+ factor = DNS_ADB_RTTADJDEFAULT;
+ } else {
+ /*
+ * We don't have an RTT for this query. Maybe the
+ * packet was lost, or maybe this server is very
+ * slow. We don't know. Increase the RTT.
+ */
+ INSIST(no_response);
+ rtt = query->addrinfo->srtt +
+ (100000 * fctx->restarts);
+ if (rtt > 10000000)
+ rtt = 10000000;
+ /*
+ * Replace the current RTT with our value.
+ */
+ factor = DNS_ADB_RTTADJREPLACE;
+ }
+ dns_adb_adjustsrtt(fctx->adb, query->addrinfo, rtt, factor);
+ }
+
+ /*
+ * Age RTTs of servers not tried.
+ */
+ factor = DNS_ADB_RTTADJAGE;
+ if (finish != NULL)
+ for (addrinfo = ISC_LIST_HEAD(fctx->forwaddrs);
+ addrinfo != NULL;
+ addrinfo = ISC_LIST_NEXT(addrinfo, publink))
+ if (UNMARKED(addrinfo))
+ dns_adb_adjustsrtt(fctx->adb, addrinfo,
+ 0, factor);
+
+ if (finish != NULL && TRIEDFIND(fctx))
+ for (find = ISC_LIST_HEAD(fctx->finds);
+ find != NULL;
+ find = ISC_LIST_NEXT(find, publink))
+ for (addrinfo = ISC_LIST_HEAD(find->list);
+ addrinfo != NULL;
+ addrinfo = ISC_LIST_NEXT(addrinfo, publink))
+ if (UNMARKED(addrinfo))
+ dns_adb_adjustsrtt(fctx->adb, addrinfo,
+ 0, factor);
+
+ if (finish != NULL && TRIEDALT(fctx)) {
+ for (addrinfo = ISC_LIST_HEAD(fctx->altaddrs);
+ addrinfo != NULL;
+ addrinfo = ISC_LIST_NEXT(addrinfo, publink))
+ if (UNMARKED(addrinfo))
+ dns_adb_adjustsrtt(fctx->adb, addrinfo,
+ 0, factor);
+ for (find = ISC_LIST_HEAD(fctx->altfinds);
+ find != NULL;
+ find = ISC_LIST_NEXT(find, publink))
+ for (addrinfo = ISC_LIST_HEAD(find->list);
+ addrinfo != NULL;
+ addrinfo = ISC_LIST_NEXT(addrinfo, publink))
+ if (UNMARKED(addrinfo))
+ dns_adb_adjustsrtt(fctx->adb, addrinfo,
+ 0, factor);
+ }
+
+ if (query->dispentry != NULL)
+ dns_dispatch_removeresponse(&query->dispentry, deventp);
+
+ ISC_LIST_UNLINK(fctx->queries, query, link);
+
+ if (query->tsig != NULL)
+ isc_buffer_free(&query->tsig);
+
+ if (query->tsigkey != NULL)
+ dns_tsigkey_detach(&query->tsigkey);
+
+ /*
+ * Check for any outstanding socket events. If they exist, cancel
+ * them and let the event handlers finish the cleanup. The resolver
+ * only needs to worry about managing the connect and send events;
+ * the dispatcher manages the recv events.
+ */
+ if (RESQUERY_CONNECTING(query))
+ /*
+ * Cancel the connect.
+ */
+ isc_socket_cancel(query->tcpsocket, NULL,
+ ISC_SOCKCANCEL_CONNECT);
+ else if (RESQUERY_SENDING(query))
+ /*
+ * Cancel the pending send.
+ */
+ isc_socket_cancel(dns_dispatch_getsocket(query->dispatch),
+ NULL, ISC_SOCKCANCEL_SEND);
+
+ if (query->dispatch != NULL)
+ dns_dispatch_detach(&query->dispatch);
+
+ if (! (RESQUERY_CONNECTING(query) || RESQUERY_SENDING(query)))
+ /*
+ * It's safe to destroy the query now.
+ */
+ resquery_destroy(&query);
+}
+
+static void
+fctx_cancelqueries(fetchctx_t *fctx, isc_boolean_t no_response) {
+ resquery_t *query, *next_query;
+
+ FCTXTRACE("cancelqueries");
+
+ for (query = ISC_LIST_HEAD(fctx->queries);
+ query != NULL;
+ query = next_query) {
+ next_query = ISC_LIST_NEXT(query, link);
+ fctx_cancelquery(&query, NULL, NULL, no_response);
+ }
+}
+
+static void
+fctx_cleanupfinds(fetchctx_t *fctx) {
+ dns_adbfind_t *find, *next_find;
+
+ REQUIRE(ISC_LIST_EMPTY(fctx->queries));
+
+ for (find = ISC_LIST_HEAD(fctx->finds);
+ find != NULL;
+ find = next_find) {
+ next_find = ISC_LIST_NEXT(find, publink);
+ ISC_LIST_UNLINK(fctx->finds, find, publink);
+ dns_adb_destroyfind(&find);
+ }
+ fctx->find = NULL;
+}
+
+static void
+fctx_cleanupaltfinds(fetchctx_t *fctx) {
+ dns_adbfind_t *find, *next_find;
+
+ REQUIRE(ISC_LIST_EMPTY(fctx->queries));
+
+ for (find = ISC_LIST_HEAD(fctx->altfinds);
+ find != NULL;
+ find = next_find) {
+ next_find = ISC_LIST_NEXT(find, publink);
+ ISC_LIST_UNLINK(fctx->altfinds, find, publink);
+ dns_adb_destroyfind(&find);
+ }
+ fctx->altfind = NULL;
+}
+
+static void
+fctx_cleanupforwaddrs(fetchctx_t *fctx) {
+ dns_adbaddrinfo_t *addr, *next_addr;
+
+ REQUIRE(ISC_LIST_EMPTY(fctx->queries));
+
+ for (addr = ISC_LIST_HEAD(fctx->forwaddrs);
+ addr != NULL;
+ addr = next_addr) {
+ next_addr = ISC_LIST_NEXT(addr, publink);
+ ISC_LIST_UNLINK(fctx->forwaddrs, addr, publink);
+ dns_adb_freeaddrinfo(fctx->adb, &addr);
+ }
+}
+
+static void
+fctx_cleanupaltaddrs(fetchctx_t *fctx) {
+ dns_adbaddrinfo_t *addr, *next_addr;
+
+ REQUIRE(ISC_LIST_EMPTY(fctx->queries));
+
+ for (addr = ISC_LIST_HEAD(fctx->altaddrs);
+ addr != NULL;
+ addr = next_addr) {
+ next_addr = ISC_LIST_NEXT(addr, publink);
+ ISC_LIST_UNLINK(fctx->altaddrs, addr, publink);
+ dns_adb_freeaddrinfo(fctx->adb, &addr);
+ }
+}
+
+static inline void
+fctx_stopeverything(fetchctx_t *fctx, isc_boolean_t no_response) {
+ FCTXTRACE("stopeverything");
+ fctx_cancelqueries(fctx, no_response);
+ fctx_cleanupfinds(fctx);
+ fctx_cleanupaltfinds(fctx);
+ fctx_cleanupforwaddrs(fctx);
+ fctx_cleanupaltaddrs(fctx);
+ fctx_stoptimer(fctx);
+}
+
+static inline void
+fctx_sendevents(fetchctx_t *fctx, isc_result_t result) {
+ dns_fetchevent_t *event, *next_event;
+ isc_task_t *task;
+
+ /*
+ * Caller must be holding the appropriate bucket lock.
+ */
+ REQUIRE(fctx->state == fetchstate_done);
+
+ FCTXTRACE("sendevents");
+
+ for (event = ISC_LIST_HEAD(fctx->events);
+ event != NULL;
+ event = next_event) {
+ next_event = ISC_LIST_NEXT(event, ev_link);
+ ISC_LIST_UNLINK(fctx->events, event, ev_link);
+ task = event->ev_sender;
+ event->ev_sender = fctx;
+ if (!HAVE_ANSWER(fctx))
+ event->result = result;
+
+ INSIST(result != ISC_R_SUCCESS ||
+ dns_rdataset_isassociated(event->rdataset) ||
+ fctx->type == dns_rdatatype_any ||
+ fctx->type == dns_rdatatype_rrsig);
+
+ isc_task_sendanddetach(&task, ISC_EVENT_PTR(&event));
+ }
+}
+
+static void
+fctx_done(fetchctx_t *fctx, isc_result_t result) {
+ dns_resolver_t *res;
+ isc_boolean_t no_response;
+
+ FCTXTRACE("done");
+
+ res = fctx->res;
+
+ if (result == ISC_R_SUCCESS)
+ no_response = ISC_TRUE;
+ else
+ no_response = ISC_FALSE;
+ fctx_stopeverything(fctx, no_response);
+
+ LOCK(&res->buckets[fctx->bucketnum].lock);
+
+ fctx->state = fetchstate_done;
+ fctx->attributes &= ~FCTX_ATTR_ADDRWAIT;
+ fctx_sendevents(fctx, result);
+
+ UNLOCK(&res->buckets[fctx->bucketnum].lock);
+}
+
+static void
+resquery_senddone(isc_task_t *task, isc_event_t *event) {
+ isc_socketevent_t *sevent = (isc_socketevent_t *)event;
+ resquery_t *query = event->ev_arg;
+
+ REQUIRE(event->ev_type == ISC_SOCKEVENT_SENDDONE);
+
+ QTRACE("senddone");
+
+ /*
+ * XXXRTH
+ *
+ * Currently we don't wait for the senddone event before retrying
+ * a query. This means that if we get really behind, we may end
+ * up doing extra work!
+ */
+
+ UNUSED(task);
+
+ INSIST(RESQUERY_SENDING(query));
+
+ query->sends--;
+
+ if (RESQUERY_CANCELED(query)) {
+ if (query->sends == 0) {
+ /*
+ * This query was canceled while the
+ * isc_socket_sendto() was in progress.
+ */
+ if (query->tcpsocket != NULL)
+ isc_socket_detach(&query->tcpsocket);
+ resquery_destroy(&query);
+ }
+ } else if (sevent->result != ISC_R_SUCCESS)
+ fctx_cancelquery(&query, NULL, NULL, ISC_FALSE);
+
+ isc_event_free(&event);
+}
+
+static inline isc_result_t
+fctx_addopt(dns_message_t *message, dns_resolver_t *res) {
+ dns_rdataset_t *rdataset;
+ dns_rdatalist_t *rdatalist;
+ dns_rdata_t *rdata;
+ isc_result_t result;
+
+ rdatalist = NULL;
+ result = dns_message_gettemprdatalist(message, &rdatalist);
+ if (result != ISC_R_SUCCESS)
+ return (result);
+ rdata = NULL;
+ result = dns_message_gettemprdata(message, &rdata);
+ if (result != ISC_R_SUCCESS)
+ return (result);
+ rdataset = NULL;
+ result = dns_message_gettemprdataset(message, &rdataset);
+ if (result != ISC_R_SUCCESS)
+ return (result);
+ dns_rdataset_init(rdataset);
+
+ rdatalist->type = dns_rdatatype_opt;
+ rdatalist->covers = 0;
+
+ /*
+ * Set Maximum UDP buffer size.
+ */
+ rdatalist->rdclass = res->udpsize;
+
+ /*
+ * Set EXTENDED-RCODE, VERSION, and Z to 0, and the DO bit to 1.
+ */
+ rdatalist->ttl = DNS_MESSAGEEXTFLAG_DO;
+
+ /*
+ * No EDNS options.
+ */
+ rdata->data = NULL;
+ rdata->length = 0;
+ rdata->rdclass = rdatalist->rdclass;
+ rdata->type = rdatalist->type;
+ rdata->flags = 0;
+
+ ISC_LIST_INIT(rdatalist->rdata);
+ ISC_LIST_APPEND(rdatalist->rdata, rdata, link);
+ RUNTIME_CHECK(dns_rdatalist_tordataset(rdatalist, rdataset) == ISC_R_SUCCESS);
+
+ return (dns_message_setopt(message, rdataset));
+}
+
+static inline void
+fctx_setretryinterval(fetchctx_t *fctx, unsigned int rtt) {
+ unsigned int seconds;
+
+ /*
+ * We retry every 2 seconds the first two times through the address
+ * list, and then we do exponential back-off.
+ */
+ if (fctx->restarts < 3)
+ seconds = 2;
+ else
+ seconds = (2 << (fctx->restarts - 1));
+
+ /*
+ * Double the round-trip time and convert to seconds.
+ */
+ rtt /= 500000;
+
+ /*
+ * Always wait for at least the doubled round-trip time.
+ */
+ if (seconds < rtt)
+ seconds = rtt;
+
+ /*
+ * But don't ever wait for more than 30 seconds.
+ */
+ if (seconds > 30)
+ seconds = 30;
+
+ isc_interval_set(&fctx->interval, seconds, 0);
+}
+
+static isc_result_t
+fctx_query(fetchctx_t *fctx, dns_adbaddrinfo_t *addrinfo,
+ unsigned int options)
+{
+ dns_resolver_t *res;
+ isc_task_t *task;
+ isc_result_t result;
+ resquery_t *query;
+
+ FCTXTRACE("query");
+
+ res = fctx->res;
+ task = res->buckets[fctx->bucketnum].task;
+
+ fctx_setretryinterval(fctx, addrinfo->srtt);
+ result = fctx_startidletimer(fctx);
+ if (result != ISC_R_SUCCESS)
+ return (result);
+
+ dns_message_reset(fctx->rmessage, DNS_MESSAGE_INTENTPARSE);
+
+ query = isc_mem_get(res->mctx, sizeof(*query));
+ if (query == NULL) {
+ result = ISC_R_NOMEMORY;
+ goto stop_idle_timer;
+ }
+ query->mctx = res->mctx;
+ query->options = options;
+ query->attributes = 0;
+ query->sends = 0;
+ query->connects = 0;
+ /*
+ * Note that the caller MUST guarantee that 'addrinfo' will remain
+ * valid until this query is canceled.
+ */
+ query->addrinfo = addrinfo;
+ TIME_NOW(&query->start);
+
+ /*
+ * If this is a TCP query, then we need to make a socket and
+ * a dispatch for it here. Otherwise we use the resolver's
+ * shared dispatch.
+ */
+ query->dispatchmgr = res->dispatchmgr;
+ query->dispatch = NULL;
+ query->tcpsocket = NULL;
+ if ((query->options & DNS_FETCHOPT_TCP) != 0) {
+ isc_sockaddr_t addr;
+ int pf;
+
+ pf = isc_sockaddr_pf(&addrinfo->sockaddr);
+
+ switch (pf) {
+ case PF_INET:
+ result = dns_dispatch_getlocaladdress(res->dispatchv4,
+ &addr);
+ break;
+ case PF_INET6:
+ result = dns_dispatch_getlocaladdress(res->dispatchv6,
+ &addr);
+ break;
+ default:
+ result = ISC_R_NOTIMPLEMENTED;
+ break;
+ }
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_query;
+
+ isc_sockaddr_setport(&addr, 0);
+
+ result = isc_socket_create(res->socketmgr, pf,
+ isc_sockettype_tcp,
+ &query->tcpsocket);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_query;
+
+ result = isc_socket_bind(query->tcpsocket, &addr);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_socket;
+
+ /*
+ * A dispatch will be created once the connect succeeds.
+ */
+ } else {
+ switch (isc_sockaddr_pf(&addrinfo->sockaddr)) {
+ case PF_INET:
+ dns_dispatch_attach(res->dispatchv4, &query->dispatch);
+ break;
+ case PF_INET6:
+ dns_dispatch_attach(res->dispatchv6, &query->dispatch);
+ break;
+ default:
+ result = ISC_R_NOTIMPLEMENTED;
+ goto cleanup_query;
+ }
+ /*
+ * We should always have a valid dispatcher here. If we
+ * don't support a protocol family, then its dispatcher
+ * will be NULL, but we shouldn't be finding addresses for
+ * protocol types we don't support, so the dispatcher
+ * we found should never be NULL.
+ */
+ INSIST(query->dispatch != NULL);
+ }
+
+ query->dispentry = NULL;
+ query->fctx = fctx;
+ query->tsig = NULL;
+ query->tsigkey = NULL;
+ ISC_LINK_INIT(query, link);
+ query->magic = QUERY_MAGIC;
+
+ if ((query->options & DNS_FETCHOPT_TCP) != 0) {
+ /*
+ * Connect to the remote server.
+ *
+ * XXXRTH Should we attach to the socket?
+ */
+ result = isc_socket_connect(query->tcpsocket,
+ &addrinfo->sockaddr, task,
+ resquery_connected, query);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_socket;
+ query->connects++;
+ QTRACE("connecting via TCP");
+ } else {
+ result = resquery_send(query);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_dispatch;
+ }
+
+ ISC_LIST_APPEND(fctx->queries, query, link);
+
+ return (ISC_R_SUCCESS);
+
+ cleanup_socket:
+ isc_socket_detach(&query->tcpsocket);
+
+ cleanup_dispatch:
+ if (query->dispatch != NULL)
+ dns_dispatch_detach(&query->dispatch);
+
+ cleanup_query:
+ query->magic = 0;
+ isc_mem_put(res->mctx, query, sizeof(*query));
+
+ stop_idle_timer:
+ RUNTIME_CHECK(fctx_stopidletimer(fctx) == ISC_R_SUCCESS);
+
+ return (result);
+}
+
+static isc_result_t
+resquery_send(resquery_t *query) {
+ fetchctx_t *fctx;
+ isc_result_t result;
+ dns_name_t *qname = NULL;
+ dns_rdataset_t *qrdataset = NULL;
+ isc_region_t r;
+ dns_resolver_t *res;
+ isc_task_t *task;
+ isc_socket_t *socket;
+ isc_buffer_t tcpbuffer;
+ isc_sockaddr_t *address;
+ isc_buffer_t *buffer;
+ isc_netaddr_t ipaddr;
+ dns_tsigkey_t *tsigkey = NULL;
+ dns_peer_t *peer = NULL;
+ isc_boolean_t useedns;
+ dns_compress_t cctx;
+ isc_boolean_t cleanup_cctx = ISC_FALSE;
+ isc_boolean_t secure_domain;
+
+ fctx = query->fctx;
+ QTRACE("send");
+
+ res = fctx->res;
+ task = res->buckets[fctx->bucketnum].task;
+ address = NULL;
+
+ if ((query->options & DNS_FETCHOPT_TCP) != 0) {
+ /*
+ * Reserve space for the TCP message length.
+ */
+ isc_buffer_init(&tcpbuffer, query->data, sizeof(query->data));
+ isc_buffer_init(&query->buffer, query->data + 2,
+ sizeof(query->data) - 2);
+ buffer = &tcpbuffer;
+ } else {
+ isc_buffer_init(&query->buffer, query->data,
+ sizeof(query->data));
+ buffer = &query->buffer;
+ }
+
+ result = dns_message_gettempname(fctx->qmessage, &qname);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_temps;
+ result = dns_message_gettemprdataset(fctx->qmessage, &qrdataset);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_temps;
+
+ /*
+ * Get a query id from the dispatch.
+ */
+ result = dns_dispatch_addresponse(query->dispatch,
+ &query->addrinfo->sockaddr,
+ task,
+ resquery_response,
+ query,
+ &query->id,
+ &query->dispentry);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_temps;
+
+ fctx->qmessage->opcode = dns_opcode_query;
+
+ /*
+ * Set up question.
+ */
+ dns_name_init(qname, NULL);
+ dns_name_clone(&fctx->name, qname);
+ dns_rdataset_init(qrdataset);
+ dns_rdataset_makequestion(qrdataset, res->rdclass, fctx->type);
+ ISC_LIST_APPEND(qname->list, qrdataset, link);
+ dns_message_addname(fctx->qmessage, qname, DNS_SECTION_QUESTION);
+ qname = NULL;
+ qrdataset = NULL;
+
+ /*
+ * Set RD if the client has requested that we do a recursive query,
+ * or if we're sending to a forwarder.
+ */
+ if ((query->options & DNS_FETCHOPT_RECURSIVE) != 0 ||
+ ISFORWARDER(query->addrinfo))
+ fctx->qmessage->flags |= DNS_MESSAGEFLAG_RD;
+
+ /*
+ * Set CD if the client says don't validate or the question is
+ * under a secure entry point.
+ */
+ if ((query->options & DNS_FETCHOPT_NOVALIDATE) == 0) {
+ result = dns_keytable_issecuredomain(res->view->secroots,
+ &fctx->name,
+ &secure_domain);
+ if (result != ISC_R_SUCCESS)
+ secure_domain = ISC_FALSE;
+ if (res->view->dlv != NULL)
+ secure_domain = ISC_TRUE;
+ if (secure_domain)
+ fctx->qmessage->flags |= DNS_MESSAGEFLAG_CD;
+ } else
+ fctx->qmessage->flags |= DNS_MESSAGEFLAG_CD;
+
+ /*
+ * We don't have to set opcode because it defaults to query.
+ */
+ fctx->qmessage->id = query->id;
+
+ /*
+ * Convert the question to wire format.
+ */
+ result = dns_compress_init(&cctx, -1, fctx->res->mctx);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_message;
+ cleanup_cctx = ISC_TRUE;
+
+ result = dns_message_renderbegin(fctx->qmessage, &cctx,
+ &query->buffer);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_message;
+
+ result = dns_message_rendersection(fctx->qmessage,
+ DNS_SECTION_QUESTION, 0);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_message;
+
+ peer = NULL;
+ isc_netaddr_fromsockaddr(&ipaddr, &query->addrinfo->sockaddr);
+ (void) dns_peerlist_peerbyaddr(fctx->res->view->peers, &ipaddr, &peer);
+
+ /*
+ * The ADB does not know about servers with "edns no". Check this,
+ * and then inform the ADB for future use.
+ */
+ if ((query->addrinfo->flags & DNS_FETCHOPT_NOEDNS0) == 0 &&
+ peer != NULL &&
+ dns_peer_getsupportedns(peer, &useedns) == ISC_R_SUCCESS &&
+ !useedns)
+ {
+ query->options |= DNS_FETCHOPT_NOEDNS0;
+ dns_adb_changeflags(fctx->adb,
+ query->addrinfo,
+ DNS_FETCHOPT_NOEDNS0,
+ DNS_FETCHOPT_NOEDNS0);
+ }
+
+ /*
+ * Use EDNS0, unless the caller doesn't want it, or we know that
+ * the remote server doesn't like it.
+ */
+ if (fctx->timeouts >= MAX_EDNS0_TIMEOUTS &&
+ (query->options & DNS_FETCHOPT_NOEDNS0) == 0) {
+ query->options |= DNS_FETCHOPT_NOEDNS0;
+ FCTXTRACE("too many timeouts, disabling EDNS0");
+ }
+
+ if ((query->options & DNS_FETCHOPT_NOEDNS0) == 0) {
+ if ((query->addrinfo->flags & DNS_FETCHOPT_NOEDNS0) == 0) {
+ result = fctx_addopt(fctx->qmessage, res);
+ if (result != ISC_R_SUCCESS) {
+ /*
+ * We couldn't add the OPT, but we'll press on.
+ * We're not using EDNS0, so set the NOEDNS0
+ * bit.
+ */
+ query->options |= DNS_FETCHOPT_NOEDNS0;
+ }
+ } else {
+ /*
+ * We know this server doesn't like EDNS0, so we
+ * won't use it. Set the NOEDNS0 bit since we're
+ * not using EDNS0.
+ */
+ query->options |= DNS_FETCHOPT_NOEDNS0;
+ }
+ }
+
+ /*
+ * If we need EDNS0 to do this query and aren't using it, we lose.
+ */
+ if (NEEDEDNS0(fctx) && (query->options & DNS_FETCHOPT_NOEDNS0) != 0) {
+ result = DNS_R_SERVFAIL;
+ goto cleanup_message;
+ }
+
+ /*
+ * Add TSIG record tailored to the current recipient.
+ */
+ result = dns_view_getpeertsig(fctx->res->view, &ipaddr, &tsigkey);
+ if (result != ISC_R_SUCCESS && result != ISC_R_NOTFOUND)
+ goto cleanup_message;
+
+ if (tsigkey != NULL) {
+ result = dns_message_settsigkey(fctx->qmessage, tsigkey);
+ dns_tsigkey_detach(&tsigkey);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_message;
+ }
+
+ result = dns_message_rendersection(fctx->qmessage,
+ DNS_SECTION_ADDITIONAL, 0);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_message;
+
+ result = dns_message_renderend(fctx->qmessage);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_message;
+
+ dns_compress_invalidate(&cctx);
+ cleanup_cctx = ISC_FALSE;
+
+ if (dns_message_gettsigkey(fctx->qmessage) != NULL) {
+ dns_tsigkey_attach(dns_message_gettsigkey(fctx->qmessage),
+ &query->tsigkey);
+ result = dns_message_getquerytsig(fctx->qmessage,
+ fctx->res->mctx,
+ &query->tsig);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_message;
+ }
+
+ /*
+ * If using TCP, write the length of the message at the beginning
+ * of the buffer.
+ */
+ if ((query->options & DNS_FETCHOPT_TCP) != 0) {
+ isc_buffer_usedregion(&query->buffer, &r);
+ isc_buffer_putuint16(&tcpbuffer, (isc_uint16_t)r.length);
+ isc_buffer_add(&tcpbuffer, r.length);
+ }
+
+ /*
+ * We're now done with the query message.
+ */
+ dns_message_reset(fctx->qmessage, DNS_MESSAGE_INTENTRENDER);
+
+ socket = dns_dispatch_getsocket(query->dispatch);
+ /*
+ * Send the query!
+ */
+ if ((query->options & DNS_FETCHOPT_TCP) == 0)
+ address = &query->addrinfo->sockaddr;
+ isc_buffer_usedregion(buffer, &r);
+
+ /*
+ * XXXRTH Make sure we don't send to ourselves! We should probably
+ * prune out these addresses when we get them from the ADB.
+ */
+ result = isc_socket_sendto(socket, &r, task, resquery_senddone,
+ query, address, NULL);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_message;
+ query->sends++;
+ QTRACE("sent");
+
+ return (ISC_R_SUCCESS);
+
+ cleanup_message:
+ if (cleanup_cctx)
+ dns_compress_invalidate(&cctx);
+
+ dns_message_reset(fctx->qmessage, DNS_MESSAGE_INTENTRENDER);
+
+ /*
+ * Stop the dispatcher from listening.
+ */
+ dns_dispatch_removeresponse(&query->dispentry, NULL);
+
+ cleanup_temps:
+ if (qname != NULL)
+ dns_message_puttempname(fctx->qmessage, &qname);
+ if (qrdataset != NULL)
+ dns_message_puttemprdataset(fctx->qmessage, &qrdataset);
+
+ return (result);
+}
+
+static void
+resquery_connected(isc_task_t *task, isc_event_t *event) {
+ isc_socketevent_t *sevent = (isc_socketevent_t *)event;
+ resquery_t *query = event->ev_arg;
+ isc_result_t result;
+
+ REQUIRE(event->ev_type == ISC_SOCKEVENT_CONNECT);
+ REQUIRE(VALID_QUERY(query));
+
+ QTRACE("connected");
+
+ UNUSED(task);
+
+ /*
+ * XXXRTH
+ *
+ * Currently we don't wait for the connect event before retrying
+ * a query. This means that if we get really behind, we may end
+ * up doing extra work!
+ */
+
+ query->connects--;
+
+ if (RESQUERY_CANCELED(query)) {
+ /*
+ * This query was canceled while the connect() was in
+ * progress.
+ */
+ isc_socket_detach(&query->tcpsocket);
+ resquery_destroy(&query);
+ } else {
+ if (sevent->result == ISC_R_SUCCESS) {
+ unsigned int attrs;
+
+ /*
+ * We are connected. Create a dispatcher and
+ * send the query.
+ */
+ attrs = 0;
+ attrs |= DNS_DISPATCHATTR_TCP;
+ attrs |= DNS_DISPATCHATTR_PRIVATE;
+ attrs |= DNS_DISPATCHATTR_CONNECTED;
+ if (isc_sockaddr_pf(&query->addrinfo->sockaddr) ==
+ AF_INET)
+ attrs |= DNS_DISPATCHATTR_IPV4;
+ else
+ attrs |= DNS_DISPATCHATTR_IPV6;
+ attrs |= DNS_DISPATCHATTR_MAKEQUERY;
+
+ result = dns_dispatch_createtcp(query->dispatchmgr,
+ query->tcpsocket,
+ query->fctx->res->taskmgr,
+ 4096, 2, 1, 1, 3, attrs,
+ &query->dispatch);
+
+ /*
+ * Regardless of whether dns_dispatch_create()
+ * succeeded or not, we don't need our reference
+ * to the socket anymore.
+ */
+ isc_socket_detach(&query->tcpsocket);
+
+ if (result == ISC_R_SUCCESS)
+ result = resquery_send(query);
+
+ if (result != ISC_R_SUCCESS) {
+ fetchctx_t *fctx = query->fctx;
+ fctx_cancelquery(&query, NULL, NULL,
+ ISC_FALSE);
+ fctx_done(fctx, result);
+ }
+ } else {
+ isc_socket_detach(&query->tcpsocket);
+ fctx_cancelquery(&query, NULL, NULL, ISC_FALSE);
+ }
+ }
+
+ isc_event_free(&event);
+}
+
+
+
+static void
+fctx_finddone(isc_task_t *task, isc_event_t *event) {
+ fetchctx_t *fctx;
+ dns_adbfind_t *find;
+ dns_resolver_t *res;
+ isc_boolean_t want_try = ISC_FALSE;
+ isc_boolean_t want_done = ISC_FALSE;
+ isc_boolean_t bucket_empty = ISC_FALSE;
+ unsigned int bucketnum;
+
+ find = event->ev_sender;
+ fctx = event->ev_arg;
+ REQUIRE(VALID_FCTX(fctx));
+ res = fctx->res;
+
+ UNUSED(task);
+
+ FCTXTRACE("finddone");
+
+ INSIST(fctx->pending > 0);
+ fctx->pending--;
+
+ if (ADDRWAIT(fctx)) {
+ /*
+ * The fetch is waiting for a name to be found.
+ */
+ INSIST(!SHUTTINGDOWN(fctx));
+ fctx->attributes &= ~FCTX_ATTR_ADDRWAIT;
+ if (event->ev_type == DNS_EVENT_ADBMOREADDRESSES)
+ want_try = ISC_TRUE;
+ else if (fctx->pending == 0) {
+ /*
+ * We've got nothing else to wait for and don't
+ * know the answer. There's nothing to do but
+ * fail the fctx.
+ */
+ want_done = ISC_TRUE;
+ }
+ } else if (SHUTTINGDOWN(fctx) && fctx->pending == 0 &&
+ ISC_LIST_EMPTY(fctx->validators)) {
+ bucketnum = fctx->bucketnum;
+ LOCK(&res->buckets[bucketnum].lock);
+ /*
+ * Note that we had to wait until we had the lock before
+ * looking at fctx->references.
+ */
+ if (fctx->references == 0)
+ bucket_empty = fctx_destroy(fctx);
+ UNLOCK(&res->buckets[bucketnum].lock);
+ }
+
+ isc_event_free(&event);
+ dns_adb_destroyfind(&find);
+
+ if (want_try)
+ fctx_try(fctx);
+ else if (want_done)
+ fctx_done(fctx, ISC_R_FAILURE);
+ else if (bucket_empty)
+ empty_bucket(res);
+}
+
+
+static inline isc_boolean_t
+bad_server(fetchctx_t *fctx, isc_sockaddr_t *address) {
+ isc_sockaddr_t *sa;
+
+ for (sa = ISC_LIST_HEAD(fctx->bad);
+ sa != NULL;
+ sa = ISC_LIST_NEXT(sa, link)) {
+ if (isc_sockaddr_equal(sa, address))
+ return (ISC_TRUE);
+ }
+
+ return (ISC_FALSE);
+}
+
+static inline isc_boolean_t
+mark_bad(fetchctx_t *fctx) {
+ dns_adbfind_t *curr;
+ dns_adbaddrinfo_t *addrinfo;
+ isc_boolean_t all_bad = ISC_TRUE;
+
+ /*
+ * Mark all known bad servers, so we don't try to talk to them
+ * again.
+ */
+
+ /*
+ * Mark any bad nameservers.
+ */
+ for (curr = ISC_LIST_HEAD(fctx->finds);
+ curr != NULL;
+ curr = ISC_LIST_NEXT(curr, publink)) {
+ for (addrinfo = ISC_LIST_HEAD(curr->list);
+ addrinfo != NULL;
+ addrinfo = ISC_LIST_NEXT(addrinfo, publink)) {
+ if (bad_server(fctx, &addrinfo->sockaddr))
+ addrinfo->flags |= FCTX_ADDRINFO_MARK;
+ else
+ all_bad = ISC_FALSE;
+ }
+ }
+
+ /*
+ * Mark any bad forwarders.
+ */
+ for (addrinfo = ISC_LIST_HEAD(fctx->forwaddrs);
+ addrinfo != NULL;
+ addrinfo = ISC_LIST_NEXT(addrinfo, publink)) {
+ if (bad_server(fctx, &addrinfo->sockaddr))
+ addrinfo->flags |= FCTX_ADDRINFO_MARK;
+ else
+ all_bad = ISC_FALSE;
+ }
+
+ /*
+ * Mark any bad alternates.
+ */
+ for (curr = ISC_LIST_HEAD(fctx->altfinds);
+ curr != NULL;
+ curr = ISC_LIST_NEXT(curr, publink)) {
+ for (addrinfo = ISC_LIST_HEAD(curr->list);
+ addrinfo != NULL;
+ addrinfo = ISC_LIST_NEXT(addrinfo, publink)) {
+ if (bad_server(fctx, &addrinfo->sockaddr))
+ addrinfo->flags |= FCTX_ADDRINFO_MARK;
+ else
+ all_bad = ISC_FALSE;
+ }
+ }
+
+ for (addrinfo = ISC_LIST_HEAD(fctx->altaddrs);
+ addrinfo != NULL;
+ addrinfo = ISC_LIST_NEXT(addrinfo, publink)) {
+ if (bad_server(fctx, &addrinfo->sockaddr))
+ addrinfo->flags |= FCTX_ADDRINFO_MARK;
+ else
+ all_bad = ISC_FALSE;
+ }
+
+ return (all_bad);
+}
+
+static void
+add_bad(fetchctx_t *fctx, isc_sockaddr_t *address, isc_result_t reason) {
+ char namebuf[DNS_NAME_FORMATSIZE];
+ char addrbuf[ISC_SOCKADDR_FORMATSIZE];
+ char classbuf[64];
+ char typebuf[64];
+ char code[64];
+ isc_buffer_t b;
+ isc_sockaddr_t *sa;
+ const char *sep1, *sep2;
+
+ if (bad_server(fctx, address)) {
+ /*
+ * We already know this server is bad.
+ */
+ return;
+ }
+
+ FCTXTRACE("add_bad");
+
+ sa = isc_mem_get(fctx->res->mctx, sizeof(*sa));
+ if (sa == NULL)
+ return;
+ *sa = *address;
+ ISC_LIST_INITANDAPPEND(fctx->bad, sa, link);
+
+ if (reason == DNS_R_LAME) /* already logged */
+ return;
+
+ if (reason == DNS_R_UNEXPECTEDRCODE) {
+ isc_buffer_init(&b, code, sizeof(code) - 1);
+ dns_rcode_totext(fctx->rmessage->rcode, &b);
+ code[isc_buffer_usedlength(&b)] = '\0';
+ sep1 = "(";
+ sep2 = ") ";
+ } else if (reason == DNS_R_UNEXPECTEDOPCODE) {
+ isc_buffer_init(&b, code, sizeof(code) - 1);
+ dns_opcode_totext((dns_opcode_t)fctx->rmessage->opcode, &b);
+ code[isc_buffer_usedlength(&b)] = '\0';
+ sep1 = "(";
+ sep2 = ") ";
+ } else {
+ code[0] = '\0';
+ sep1 = "";
+ sep2 = "";
+ }
+ dns_name_format(&fctx->name, namebuf, sizeof(namebuf));
+ dns_rdatatype_format(fctx->type, typebuf, sizeof(typebuf));
+ dns_rdataclass_format(fctx->res->rdclass, classbuf, sizeof(classbuf));
+ isc_sockaddr_format(address, addrbuf, sizeof(addrbuf));
+ isc_log_write(dns_lctx, DNS_LOGCATEGORY_LAME_SERVERS,
+ DNS_LOGMODULE_RESOLVER, ISC_LOG_INFO,
+ "%s %s%s%sresolving '%s/%s/%s': %s",
+ dns_result_totext(reason), sep1, code, sep2,
+ namebuf, typebuf, classbuf, addrbuf);
+}
+
+static void
+sort_adbfind(dns_adbfind_t *find) {
+ dns_adbaddrinfo_t *best, *curr;
+ dns_adbaddrinfolist_t sorted;
+
+ /*
+ * Lame N^2 bubble sort.
+ */
+
+ ISC_LIST_INIT(sorted);
+ while (!ISC_LIST_EMPTY(find->list)) {
+ best = ISC_LIST_HEAD(find->list);
+ curr = ISC_LIST_NEXT(best, publink);
+ while (curr != NULL) {
+ if (curr->srtt < best->srtt)
+ best = curr;
+ curr = ISC_LIST_NEXT(curr, publink);
+ }
+ ISC_LIST_UNLINK(find->list, best, publink);
+ ISC_LIST_APPEND(sorted, best, publink);
+ }
+ find->list = sorted;
+}
+
+static void
+sort_finds(fetchctx_t *fctx) {
+ dns_adbfind_t *best, *curr;
+ dns_adbfindlist_t sorted;
+ dns_adbaddrinfo_t *addrinfo, *bestaddrinfo;
+
+ /*
+ * Lame N^2 bubble sort.
+ */
+
+ ISC_LIST_INIT(sorted);
+ while (!ISC_LIST_EMPTY(fctx->finds)) {
+ best = ISC_LIST_HEAD(fctx->finds);
+ bestaddrinfo = ISC_LIST_HEAD(best->list);
+ INSIST(bestaddrinfo != NULL);
+ curr = ISC_LIST_NEXT(best, publink);
+ while (curr != NULL) {
+ addrinfo = ISC_LIST_HEAD(curr->list);
+ INSIST(addrinfo != NULL);
+ if (addrinfo->srtt < bestaddrinfo->srtt) {
+ best = curr;
+ bestaddrinfo = addrinfo;
+ }
+ curr = ISC_LIST_NEXT(curr, publink);
+ }
+ ISC_LIST_UNLINK(fctx->finds, best, publink);
+ ISC_LIST_APPEND(sorted, best, publink);
+ }
+ fctx->finds = sorted;
+
+ ISC_LIST_INIT(sorted);
+ while (!ISC_LIST_EMPTY(fctx->altfinds)) {
+ best = ISC_LIST_HEAD(fctx->altfinds);
+ bestaddrinfo = ISC_LIST_HEAD(best->list);
+ INSIST(bestaddrinfo != NULL);
+ curr = ISC_LIST_NEXT(best, publink);
+ while (curr != NULL) {
+ addrinfo = ISC_LIST_HEAD(curr->list);
+ INSIST(addrinfo != NULL);
+ if (addrinfo->srtt < bestaddrinfo->srtt) {
+ best = curr;
+ bestaddrinfo = addrinfo;
+ }
+ curr = ISC_LIST_NEXT(curr, publink);
+ }
+ ISC_LIST_UNLINK(fctx->altfinds, best, publink);
+ ISC_LIST_APPEND(sorted, best, publink);
+ }
+ fctx->altfinds = sorted;
+}
+
+static void
+findname(fetchctx_t *fctx, dns_name_t *name, in_port_t port,
+ unsigned int options, unsigned int flags, isc_stdtime_t now,
+ isc_boolean_t *pruned, isc_boolean_t *need_alternate)
+{
+ dns_adbaddrinfo_t *ai;
+ dns_adbfind_t *find;
+ dns_resolver_t *res;
+ isc_boolean_t unshared;
+ isc_result_t result;
+
+ res = fctx->res;
+ unshared = ISC_TF((fctx->options | DNS_FETCHOPT_UNSHARED) != 0);
+ /*
+ * If this name is a subdomain of the query domain, tell
+ * the ADB to start looking using zone/hint data. This keeps us
+ * from getting stuck if the nameserver is beneath the zone cut
+ * and we don't know its address (e.g. because the A record has
+ * expired).
+ */
+ if (dns_name_issubdomain(name, &fctx->domain))
+ options |= DNS_ADBFIND_STARTATZONE;
+ options |= DNS_ADBFIND_GLUEOK;
+ options |= DNS_ADBFIND_HINTOK;
+
+ /*
+ * See what we know about this address.
+ */
+ find = NULL;
+ result = dns_adb_createfind(fctx->adb,
+ res->buckets[fctx->bucketnum].task,
+ fctx_finddone, fctx, name,
+ &fctx->domain, options, now, NULL,
+ res->view->dstport, &find);
+ if (result != ISC_R_SUCCESS) {
+ if (result == DNS_R_ALIAS) {
+ /*
+ * XXXRTH Follow the CNAME/DNAME chain?
+ */
+ dns_adb_destroyfind(&find);
+ }
+ } else if (!ISC_LIST_EMPTY(find->list)) {
+ /*
+ * We have at least some of the addresses for the
+ * name.
+ */
+ INSIST((find->options & DNS_ADBFIND_WANTEVENT) == 0);
+ sort_adbfind(find);
+ if (flags != 0 || port != 0) {
+ for (ai = ISC_LIST_HEAD(find->list);
+ ai != NULL;
+ ai = ISC_LIST_NEXT(ai, publink)) {
+ ai->flags |= flags;
+ if (port != 0)
+ isc_sockaddr_setport(&ai->sockaddr,
+ port);
+ }
+ }
+ if ((flags & FCTX_ADDRINFO_FORWARDER) != 0)
+ ISC_LIST_APPEND(fctx->altfinds, find, publink);
+ else
+ ISC_LIST_APPEND(fctx->finds, find, publink);
+ } else {
+ /*
+ * We don't know any of the addresses for this
+ * name.
+ */
+ if ((find->options & DNS_ADBFIND_WANTEVENT) != 0) {
+ /*
+ * We're looking for them and will get an
+ * event about it later.
+ */
+ fctx->pending++;
+ /*
+ * Bootstrap.
+ */
+ if (need_alternate != NULL &&
+ !*need_alternate && unshared &&
+ ((res->dispatchv4 == NULL &&
+ find->result_v6 != DNS_R_NXDOMAIN) ||
+ (res->dispatchv6 == NULL &&
+ find->result_v4 != DNS_R_NXDOMAIN)))
+ *need_alternate = ISC_TRUE;
+ } else {
+ /*
+ * If we know there are no addresses for
+ * the family we are using then try to add
+ * an alternative server.
+ */
+ if (need_alternate != NULL && !*need_alternate &&
+ ((res->dispatchv4 == NULL &&
+ find->result_v6 == DNS_R_NXRRSET) ||
+ (res->dispatchv6 == NULL &&
+ find->result_v4 == DNS_R_NXRRSET)))
+ *need_alternate = ISC_TRUE;
+ /*
+ * And ADB isn't going to send us any events
+ * either. This find loses.
+ */
+ if ((find->options & DNS_ADBFIND_LAMEPRUNED) != 0) {
+ /*
+ * The ADB pruned lame servers for
+ * this name. Remember that in case
+ * we get desperate later on.
+ */
+ *pruned = ISC_TRUE;
+ }
+ dns_adb_destroyfind(&find);
+ }
+ }
+}
+
+static isc_result_t
+fctx_getaddresses(fetchctx_t *fctx) {
+ dns_rdata_t rdata = DNS_RDATA_INIT;
+ isc_result_t result;
+ dns_resolver_t *res;
+ isc_stdtime_t now;
+ unsigned int stdoptions;
+ isc_sockaddr_t *sa;
+ dns_adbaddrinfo_t *ai;
+ isc_boolean_t pruned, all_bad;
+ dns_rdata_ns_t ns;
+ isc_boolean_t need_alternate = ISC_FALSE;
+ isc_boolean_t unshared;
+
+ FCTXTRACE("getaddresses");
+
+ /*
+ * Don't pound on remote servers. (Failsafe!)
+ */
+ fctx->restarts++;
+ if (fctx->restarts > 10) {
+ FCTXTRACE("too many restarts");
+ return (DNS_R_SERVFAIL);
+ }
+
+ res = fctx->res;
+ pruned = ISC_FALSE;
+ stdoptions = 0; /* Keep compiler happy. */
+ unshared = ISC_TF((fctx->options | DNS_FETCHOPT_UNSHARED) != 0);
+
+ /*
+ * Forwarders.
+ */
+
+ INSIST(ISC_LIST_EMPTY(fctx->forwaddrs));
+ INSIST(ISC_LIST_EMPTY(fctx->altaddrs));
+
+ /*
+ * If this fctx has forwarders, use them; otherwise use any
+ * selective forwarders specified in the view; otherwise use the
+ * resolver's forwarders (if any).
+ */
+ sa = ISC_LIST_HEAD(fctx->forwarders);
+ if (sa == NULL) {
+ dns_forwarders_t *forwarders = NULL;
+ dns_name_t *name = &fctx->name;
+ dns_name_t suffix;
+ unsigned int labels;
+
+ /*
+ * DS records are found in the parent server.
+ * Strip label to get the correct forwarder (if any).
+ */
+ if (fctx->type == dns_rdatatype_ds &&
+ dns_name_countlabels(name) > 1) {
+ dns_name_init(&suffix, NULL);
+ labels = dns_name_countlabels(name);
+ dns_name_getlabelsequence(name, 1, labels - 1, &suffix);
+ name = &suffix;
+ }
+ result = dns_fwdtable_find(fctx->res->view->fwdtable, name,
+ &forwarders);
+ if (result == ISC_R_SUCCESS) {
+ sa = ISC_LIST_HEAD(forwarders->addrs);
+ fctx->fwdpolicy = forwarders->fwdpolicy;
+ }
+ }
+
+ while (sa != NULL) {
+ ai = NULL;
+ result = dns_adb_findaddrinfo(fctx->adb,
+ sa, &ai, 0); /* XXXMLG */
+ if (result == ISC_R_SUCCESS) {
+ dns_adbaddrinfo_t *cur;
+ ai->flags |= FCTX_ADDRINFO_FORWARDER;
+ cur = ISC_LIST_HEAD(fctx->forwaddrs);
+ while (cur != NULL && cur->srtt < ai->srtt)
+ cur = ISC_LIST_NEXT(cur, publink);
+ if (cur != NULL)
+ ISC_LIST_INSERTBEFORE(fctx->forwaddrs, cur,
+ ai, publink);
+ else
+ ISC_LIST_APPEND(fctx->forwaddrs, ai, publink);
+ }
+ sa = ISC_LIST_NEXT(sa, link);
+ }
+
+ /*
+ * If the forwarding policy is "only", we don't need the addresses
+ * of the nameservers.
+ */
+ if (fctx->fwdpolicy == dns_fwdpolicy_only)
+ goto out;
+
+ /*
+ * Normal nameservers.
+ */
+
+ stdoptions = DNS_ADBFIND_WANTEVENT | DNS_ADBFIND_EMPTYEVENT;
+ if (fctx->restarts == 1) {
+ /*
+ * To avoid sending out a flood of queries likely to
+ * result in NXRRSET, we suppress fetches for address
+ * families we don't have the first time through,
+ * provided that we have addresses in some family we
+ * can use.
+ *
+ * We don't want to set this option all the time, since
+ * if fctx->restarts > 1, we've clearly been having trouble
+ * with the addresses we had, so getting more could help.
+ */
+ stdoptions |= DNS_ADBFIND_AVOIDFETCHES;
+ }
+ if (res->dispatchv4 != NULL)
+ stdoptions |= DNS_ADBFIND_INET;
+ if (res->dispatchv6 != NULL)
+ stdoptions |= DNS_ADBFIND_INET6;
+ isc_stdtime_get(&now);
+
+ restart:
+ INSIST(ISC_LIST_EMPTY(fctx->finds));
+ INSIST(ISC_LIST_EMPTY(fctx->altfinds));
+
+ for (result = dns_rdataset_first(&fctx->nameservers);
+ result == ISC_R_SUCCESS;
+ result = dns_rdataset_next(&fctx->nameservers))
+ {
+ dns_rdataset_current(&fctx->nameservers, &rdata);
+ /*
+ * Extract the name from the NS record.
+ */
+ result = dns_rdata_tostruct(&rdata, &ns, NULL);
+ if (result != ISC_R_SUCCESS)
+ continue;
+
+ findname(fctx, &ns.name, 0, stdoptions, 0, now,
+ &pruned, &need_alternate);
+ dns_rdata_reset(&rdata);
+ dns_rdata_freestruct(&ns);
+ }
+ if (result != ISC_R_NOMORE)
+ return (result);
+
+ /*
+ * Do we need to use 6 to 4?
+ */
+ if (need_alternate) {
+ int family;
+ alternate_t *a;
+ family = (res->dispatchv6 != NULL) ? AF_INET6 : AF_INET;
+ for (a = ISC_LIST_HEAD(fctx->res->alternates);
+ a != NULL;
+ a = ISC_LIST_NEXT(a, link)) {
+ if (!a->isaddress) {
+ findname(fctx, &a->_u._n.name, a->_u._n.port,
+ stdoptions, FCTX_ADDRINFO_FORWARDER,
+ now, &pruned, NULL);
+ continue;
+ }
+ if (isc_sockaddr_pf(&a->_u.addr) != family)
+ continue;
+ ai = NULL;
+ result = dns_adb_findaddrinfo(fctx->adb, &a->_u.addr,
+ &ai, 0);
+ if (result == ISC_R_SUCCESS) {
+ dns_adbaddrinfo_t *cur;
+ ai->flags |= FCTX_ADDRINFO_FORWARDER;
+ cur = ISC_LIST_HEAD(fctx->altaddrs);
+ while (cur != NULL && cur->srtt < ai->srtt)
+ cur = ISC_LIST_NEXT(cur, publink);
+ if (cur != NULL)
+ ISC_LIST_INSERTBEFORE(fctx->altaddrs,
+ cur, ai, publink);
+ else
+ ISC_LIST_APPEND(fctx->altaddrs, ai,
+ publink);
+ }
+ }
+ }
+
+ out:
+ /*
+ * Mark all known bad servers.
+ */
+ all_bad = mark_bad(fctx);
+
+ /*
+ * How are we doing?
+ */
+ if (all_bad) {
+ /*
+ * We've got no addresses.
+ */
+ if (fctx->pending > 0) {
+ /*
+ * We're fetching the addresses, but don't have any
+ * yet. Tell the caller to wait for an answer.
+ */
+ result = DNS_R_WAIT;
+ } else if (pruned) {
+ /*
+ * Some addresses were removed by lame pruning.
+ * Turn pruning off and try again.
+ */
+ FCTXTRACE("restarting with returnlame");
+ INSIST((stdoptions & DNS_ADBFIND_RETURNLAME) == 0);
+ stdoptions |= DNS_ADBFIND_RETURNLAME;
+ pruned = ISC_FALSE;
+ fctx_cleanupaltfinds(fctx);
+ fctx_cleanupfinds(fctx);
+ goto restart;
+ } else {
+ /*
+ * We've lost completely. We don't know any
+ * addresses, and the ADB has told us it can't get
+ * them.
+ */
+ FCTXTRACE("no addresses");
+ result = ISC_R_FAILURE;
+ }
+ } else {
+ /*
+ * We've found some addresses. We might still be looking
+ * for more addresses.
+ */
+ sort_finds(fctx);
+ result = ISC_R_SUCCESS;
+ }
+
+ return (result);
+}
+
+static inline void
+possibly_mark(fetchctx_t *fctx, dns_adbaddrinfo_t *addr)
+{
+ isc_netaddr_t na;
+ char buf[ISC_NETADDR_FORMATSIZE];
+ isc_sockaddr_t *sa;
+ isc_boolean_t aborted = ISC_FALSE;
+ isc_boolean_t bogus;
+ dns_acl_t *blackhole;
+ isc_netaddr_t ipaddr;
+ dns_peer_t *peer = NULL;
+ dns_resolver_t *res;
+ const char *msg = NULL;
+
+ sa = &addr->sockaddr;
+
+ res = fctx->res;
+ isc_netaddr_fromsockaddr(&ipaddr, sa);
+ blackhole = dns_dispatchmgr_getblackhole(res->dispatchmgr);
+ (void) dns_peerlist_peerbyaddr(res->view->peers, &ipaddr, &peer);
+
+ if (blackhole != NULL) {
+ int match;
+
+ if (dns_acl_match(&ipaddr, NULL, blackhole,
+ &res->view->aclenv,
+ &match, NULL) == ISC_R_SUCCESS &&
+ match > 0)
+ aborted = ISC_TRUE;
+ }
+
+ if (peer != NULL &&
+ dns_peer_getbogus(peer, &bogus) == ISC_R_SUCCESS &&
+ bogus)
+ aborted = ISC_TRUE;
+
+ if (aborted) {
+ addr->flags |= FCTX_ADDRINFO_MARK;
+ msg = "ignoring blackholed / bogus server: ";
+ } else if (isc_sockaddr_ismulticast(sa)) {
+ addr->flags |= FCTX_ADDRINFO_MARK;
+ msg = "ignoring multicast address: ";
+ } else if (isc_sockaddr_isexperimental(sa)) {
+ addr->flags |= FCTX_ADDRINFO_MARK;
+ msg = "ignoring experimental address: ";
+ } else if (sa->type.sa.sa_family != AF_INET6) {
+ return;
+ } else if (IN6_IS_ADDR_V4MAPPED(&sa->type.sin6.sin6_addr)) {
+ addr->flags |= FCTX_ADDRINFO_MARK;
+ msg = "ignoring IPv6 mapped IPV4 address: ";
+ } else if (IN6_IS_ADDR_V4COMPAT(&sa->type.sin6.sin6_addr)) {
+ addr->flags |= FCTX_ADDRINFO_MARK;
+ msg = "ignoring IPv6 compatibility IPV4 address: ";
+ } else
+ return;
+
+ if (!isc_log_wouldlog(dns_lctx, ISC_LOG_DEBUG(3)))
+ return;
+
+ isc_netaddr_fromsockaddr(&na, sa);
+ isc_netaddr_format(&na, buf, sizeof(buf));
+ FCTXTRACE2(msg, buf);
+}
+
+static inline dns_adbaddrinfo_t *
+fctx_nextaddress(fetchctx_t *fctx) {
+ dns_adbfind_t *find, *start;
+ dns_adbaddrinfo_t *addrinfo;
+ dns_adbaddrinfo_t *faddrinfo;
+
+ /*
+ * Return the next untried address, if any.
+ */
+
+ /*
+ * Find the first unmarked forwarder (if any).
+ */
+ for (addrinfo = ISC_LIST_HEAD(fctx->forwaddrs);
+ addrinfo != NULL;
+ addrinfo = ISC_LIST_NEXT(addrinfo, publink)) {
+ if (!UNMARKED(addrinfo))
+ continue;
+ possibly_mark(fctx, addrinfo);
+ if (UNMARKED(addrinfo)) {
+ addrinfo->flags |= FCTX_ADDRINFO_MARK;
+ fctx->find = NULL;
+ return (addrinfo);
+ }
+ }
+
+ /*
+ * No forwarders. Move to the next find.
+ */
+
+ fctx->attributes |= FCTX_ATTR_TRIEDFIND;
+
+ find = fctx->find;
+ if (find == NULL)
+ find = ISC_LIST_HEAD(fctx->finds);
+ else {
+ find = ISC_LIST_NEXT(find, publink);
+ if (find == NULL)
+ find = ISC_LIST_HEAD(fctx->finds);
+ }
+
+ /*
+ * Find the first unmarked addrinfo.
+ */
+ addrinfo = NULL;
+ if (find != NULL) {
+ start = find;
+ do {
+ for (addrinfo = ISC_LIST_HEAD(find->list);
+ addrinfo != NULL;
+ addrinfo = ISC_LIST_NEXT(addrinfo, publink)) {
+ if (!UNMARKED(addrinfo))
+ continue;
+ possibly_mark(fctx, addrinfo);
+ if (UNMARKED(addrinfo)) {
+ addrinfo->flags |= FCTX_ADDRINFO_MARK;
+ break;
+ }
+ }
+ if (addrinfo != NULL)
+ break;
+ find = ISC_LIST_NEXT(find, publink);
+ if (find == NULL)
+ find = ISC_LIST_HEAD(fctx->finds);
+ } while (find != start);
+ }
+
+ fctx->find = find;
+ if (addrinfo != NULL)
+ return (addrinfo);
+
+ /*
+ * No nameservers left. Try alternates.
+ */
+
+ fctx->attributes |= FCTX_ATTR_TRIEDALT;
+
+ find = fctx->altfind;
+ if (find == NULL)
+ find = ISC_LIST_HEAD(fctx->altfinds);
+ else {
+ find = ISC_LIST_NEXT(find, publink);
+ if (find == NULL)
+ find = ISC_LIST_HEAD(fctx->altfinds);
+ }
+
+ /*
+ * Find the first unmarked addrinfo.
+ */
+ addrinfo = NULL;
+ if (find != NULL) {
+ start = find;
+ do {
+ for (addrinfo = ISC_LIST_HEAD(find->list);
+ addrinfo != NULL;
+ addrinfo = ISC_LIST_NEXT(addrinfo, publink)) {
+ if (!UNMARKED(addrinfo))
+ continue;
+ possibly_mark(fctx, addrinfo);
+ if (UNMARKED(addrinfo)) {
+ addrinfo->flags |= FCTX_ADDRINFO_MARK;
+ break;
+ }
+ }
+ if (addrinfo != NULL)
+ break;
+ find = ISC_LIST_NEXT(find, publink);
+ if (find == NULL)
+ find = ISC_LIST_HEAD(fctx->altfinds);
+ } while (find != start);
+ }
+
+ faddrinfo = addrinfo;
+
+ /*
+ * See if we have a better alternate server by address.
+ */
+
+ for (addrinfo = ISC_LIST_HEAD(fctx->altaddrs);
+ addrinfo != NULL;
+ addrinfo = ISC_LIST_NEXT(addrinfo, publink)) {
+ if (!UNMARKED(addrinfo))
+ continue;
+ possibly_mark(fctx, addrinfo);
+ if (UNMARKED(addrinfo) &&
+ (faddrinfo == NULL ||
+ addrinfo->srtt < faddrinfo->srtt)) {
+ if (faddrinfo != NULL)
+ faddrinfo->flags &= ~FCTX_ADDRINFO_MARK;
+ addrinfo->flags |= FCTX_ADDRINFO_MARK;
+ break;
+ }
+ }
+
+ if (addrinfo == NULL) {
+ addrinfo = faddrinfo;
+ fctx->altfind = find;
+ }
+
+ return (addrinfo);
+}
+
+static void
+fctx_try(fetchctx_t *fctx) {
+ isc_result_t result;
+ dns_adbaddrinfo_t *addrinfo;
+
+ FCTXTRACE("try");
+
+ REQUIRE(!ADDRWAIT(fctx));
+
+ addrinfo = fctx_nextaddress(fctx);
+ if (addrinfo == NULL) {
+ /*
+ * We have no more addresses. Start over.
+ */
+ fctx_cancelqueries(fctx, ISC_TRUE);
+ fctx_cleanupfinds(fctx);
+ fctx_cleanupaltfinds(fctx);
+ fctx_cleanupforwaddrs(fctx);
+ fctx_cleanupaltaddrs(fctx);
+ result = fctx_getaddresses(fctx);
+ if (result == DNS_R_WAIT) {
+ /*
+ * Sleep waiting for addresses.
+ */
+ FCTXTRACE("addrwait");
+ fctx->attributes |= FCTX_ATTR_ADDRWAIT;
+ return;
+ } else if (result != ISC_R_SUCCESS) {
+ /*
+ * Something bad happened.
+ */
+ fctx_done(fctx, result);
+ return;
+ }
+
+ addrinfo = fctx_nextaddress(fctx);
+ /*
+ * While we may have addresses from the ADB, they
+ * might be bad ones. In this case, return SERVFAIL.
+ */
+ if (addrinfo == NULL) {
+ fctx_done(fctx, DNS_R_SERVFAIL);
+ return;
+ }
+ }
+
+ result = fctx_query(fctx, addrinfo, fctx->options);
+ if (result != ISC_R_SUCCESS)
+ fctx_done(fctx, result);
+}
+
+static isc_boolean_t
+fctx_destroy(fetchctx_t *fctx) {
+ dns_resolver_t *res;
+ unsigned int bucketnum;
+ isc_sockaddr_t *sa, *next_sa;
+
+ /*
+ * Caller must be holding the bucket lock.
+ */
+
+ REQUIRE(VALID_FCTX(fctx));
+ REQUIRE(fctx->state == fetchstate_done ||
+ fctx->state == fetchstate_init);
+ REQUIRE(ISC_LIST_EMPTY(fctx->events));
+ REQUIRE(ISC_LIST_EMPTY(fctx->queries));
+ REQUIRE(ISC_LIST_EMPTY(fctx->finds));
+ REQUIRE(ISC_LIST_EMPTY(fctx->altfinds));
+ REQUIRE(fctx->pending == 0);
+ REQUIRE(ISC_LIST_EMPTY(fctx->validators));
+ REQUIRE(fctx->references == 0);
+
+ FCTXTRACE("destroy");
+
+ res = fctx->res;
+ bucketnum = fctx->bucketnum;
+
+ ISC_LIST_UNLINK(res->buckets[bucketnum].fctxs, fctx, link);
+
+ /*
+ * Free bad.
+ */
+ for (sa = ISC_LIST_HEAD(fctx->bad);
+ sa != NULL;
+ sa = next_sa) {
+ next_sa = ISC_LIST_NEXT(sa, link);
+ ISC_LIST_UNLINK(fctx->bad, sa, link);
+ isc_mem_put(res->mctx, sa, sizeof(*sa));
+ }
+
+ isc_timer_detach(&fctx->timer);
+ dns_message_destroy(&fctx->rmessage);
+ dns_message_destroy(&fctx->qmessage);
+ if (dns_name_countlabels(&fctx->domain) > 0)
+ dns_name_free(&fctx->domain, res->mctx);
+ if (dns_rdataset_isassociated(&fctx->nameservers))
+ dns_rdataset_disassociate(&fctx->nameservers);
+ dns_name_free(&fctx->name, res->mctx);
+ dns_db_detach(&fctx->cache);
+ dns_adb_detach(&fctx->adb);
+ isc_mem_free(res->mctx, fctx->info);
+ isc_mem_put(res->mctx, fctx, sizeof(*fctx));
+
+ LOCK(&res->nlock);
+ res->nfctx--;
+ UNLOCK(&res->nlock);
+
+ if (res->buckets[bucketnum].exiting &&
+ ISC_LIST_EMPTY(res->buckets[bucketnum].fctxs))
+ return (ISC_TRUE);
+
+ return (ISC_FALSE);
+}
+
+/*
+ * Fetch event handlers.
+ */
+
+static void
+fctx_timeout(isc_task_t *task, isc_event_t *event) {
+ fetchctx_t *fctx = event->ev_arg;
+
+ REQUIRE(VALID_FCTX(fctx));
+
+ UNUSED(task);
+
+ FCTXTRACE("timeout");
+
+ if (event->ev_type == ISC_TIMEREVENT_LIFE) {
+ fctx_done(fctx, ISC_R_TIMEDOUT);
+ } else {
+ isc_result_t result;
+
+ fctx->timeouts++;
+ /*
+ * We could cancel the running queries here, or we could let
+ * them keep going. Right now we choose the latter...
+ */
+ fctx->attributes &= ~FCTX_ATTR_ADDRWAIT;
+ /*
+ * Our timer has triggered. Reestablish the fctx lifetime
+ * timer.
+ */
+ result = fctx_starttimer(fctx);
+ if (result != ISC_R_SUCCESS)
+ fctx_done(fctx, result);
+ else
+ /*
+ * Keep trying.
+ */
+ fctx_try(fctx);
+ }
+
+ isc_event_free(&event);
+}
+
+static void
+fctx_shutdown(fetchctx_t *fctx) {
+ isc_event_t *cevent;
+
+ /*
+ * Start the shutdown process for fctx, if it isn't already underway.
+ */
+
+ FCTXTRACE("shutdown");
+
+ /*
+ * The caller must be holding the appropriate bucket lock.
+ */
+
+ if (fctx->want_shutdown)
+ return;
+
+ fctx->want_shutdown = ISC_TRUE;
+
+ /*
+ * Unless we're still initializing (in which case the
+ * control event is still outstanding), we need to post
+ * the control event to tell the fetch we want it to
+ * exit.
+ */
+ if (fctx->state != fetchstate_init) {
+ cevent = &fctx->control_event;
+ isc_task_send(fctx->res->buckets[fctx->bucketnum].task,
+ &cevent);
+ }
+}
+
+static void
+fctx_doshutdown(isc_task_t *task, isc_event_t *event) {
+ fetchctx_t *fctx = event->ev_arg;
+ isc_boolean_t bucket_empty = ISC_FALSE;
+ dns_resolver_t *res;
+ unsigned int bucketnum;
+ dns_validator_t *validator;
+
+ REQUIRE(VALID_FCTX(fctx));
+
+ UNUSED(task);
+
+ res = fctx->res;
+ bucketnum = fctx->bucketnum;
+
+ FCTXTRACE("doshutdown");
+
+ /*
+ * An fctx that is shutting down is no longer in ADDRWAIT mode.
+ */
+ fctx->attributes &= ~FCTX_ATTR_ADDRWAIT;
+
+ /*
+ * Cancel all pending validators. Note that this must be done
+ * without the bucket lock held, since that could cause deadlock.
+ */
+ validator = ISC_LIST_HEAD(fctx->validators);
+ while (validator != NULL) {
+ dns_validator_cancel(validator);
+ validator = ISC_LIST_NEXT(validator, link);
+ }
+
+ if (fctx->nsfetch != NULL)
+ dns_resolver_cancelfetch(fctx->nsfetch);
+
+ /*
+ * Shut down anything that is still running on behalf of this
+ * fetch. To avoid deadlock with the ADB, we must do this
+ * before we lock the bucket lock.
+ */
+ fctx_stopeverything(fctx, ISC_FALSE);
+
+ LOCK(&res->buckets[bucketnum].lock);
+
+ fctx->attributes |= FCTX_ATTR_SHUTTINGDOWN;
+
+ INSIST(fctx->state == fetchstate_active ||
+ fctx->state == fetchstate_done);
+ INSIST(fctx->want_shutdown);
+
+ if (fctx->state != fetchstate_done) {
+ fctx->state = fetchstate_done;
+ fctx_sendevents(fctx, ISC_R_CANCELED);
+ }
+
+ if (fctx->references == 0 && fctx->pending == 0 &&
+ ISC_LIST_EMPTY(fctx->validators))
+ bucket_empty = fctx_destroy(fctx);
+
+ UNLOCK(&res->buckets[bucketnum].lock);
+
+ if (bucket_empty)
+ empty_bucket(res);
+}
+
+static void
+fctx_start(isc_task_t *task, isc_event_t *event) {
+ fetchctx_t *fctx = event->ev_arg;
+ isc_boolean_t done = ISC_FALSE, bucket_empty = ISC_FALSE;
+ dns_resolver_t *res;
+ unsigned int bucketnum;
+
+ REQUIRE(VALID_FCTX(fctx));
+
+ UNUSED(task);
+
+ res = fctx->res;
+ bucketnum = fctx->bucketnum;
+
+ FCTXTRACE("start");
+
+ LOCK(&res->buckets[bucketnum].lock);
+
+ INSIST(fctx->state == fetchstate_init);
+ if (fctx->want_shutdown) {
+ /*
+ * We haven't started this fctx yet, and we've been requested
+ * to shut it down.
+ */
+ fctx->attributes |= FCTX_ATTR_SHUTTINGDOWN;
+ fctx->state = fetchstate_done;
+ fctx_sendevents(fctx, ISC_R_CANCELED);
+ /*
+ * Since we haven't started, we INSIST that we have no
+ * pending ADB finds and no pending validations.
+ */
+ INSIST(fctx->pending == 0);
+ INSIST(ISC_LIST_EMPTY(fctx->validators));
+ if (fctx->references == 0) {
+ /*
+ * It's now safe to destroy this fctx.
+ */
+ bucket_empty = fctx_destroy(fctx);
+ }
+ done = ISC_TRUE;
+ } else {
+ /*
+ * Normal fctx startup.
+ */
+ fctx->state = fetchstate_active;
+ /*
+ * Reset the control event for later use in shutting down
+ * the fctx.
+ */
+ ISC_EVENT_INIT(event, sizeof(*event), 0, NULL,
+ DNS_EVENT_FETCHCONTROL, fctx_doshutdown, fctx,
+ NULL, NULL, NULL);
+ }
+
+ UNLOCK(&res->buckets[bucketnum].lock);
+
+ if (!done) {
+ isc_result_t result;
+
+ /*
+ * All is well. Start working on the fetch.
+ */
+ result = fctx_starttimer(fctx);
+ if (result != ISC_R_SUCCESS)
+ fctx_done(fctx, result);
+ else
+ fctx_try(fctx);
+ } else if (bucket_empty)
+ empty_bucket(res);
+}
+
+/*
+ * Fetch Creation, Joining, and Cancelation.
+ */
+
+static inline isc_result_t
+fctx_join(fetchctx_t *fctx, isc_task_t *task, isc_taskaction_t action,
+ void *arg, dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset,
+ dns_fetch_t *fetch)
+{
+ isc_task_t *clone;
+ dns_fetchevent_t *event;
+
+ FCTXTRACE("join");
+
+ /*
+ * We store the task we're going to send this event to in the
+ * sender field. We'll make the fetch the sender when we actually
+ * send the event.
+ */
+ clone = NULL;
+ isc_task_attach(task, &clone);
+ event = (dns_fetchevent_t *)
+ isc_event_allocate(fctx->res->mctx, clone,
+ DNS_EVENT_FETCHDONE,
+ action, arg, sizeof(*event));
+ if (event == NULL) {
+ isc_task_detach(&clone);
+ return (ISC_R_NOMEMORY);
+ }
+ event->result = DNS_R_SERVFAIL;
+ event->qtype = fctx->type;
+ event->db = NULL;
+ event->node = NULL;
+ event->rdataset = rdataset;
+ event->sigrdataset = sigrdataset;
+ event->fetch = fetch;
+ dns_fixedname_init(&event->foundname);
+
+ /*
+ * Make sure that we can store the sigrdataset in the
+ * first event if it is needed by any of the events.
+ */
+ if (event->sigrdataset != NULL)
+ ISC_LIST_PREPEND(fctx->events, event, ev_link);
+ else
+ ISC_LIST_APPEND(fctx->events, event, ev_link);
+ fctx->references++;
+
+ fetch->magic = DNS_FETCH_MAGIC;
+ fetch->private = fctx;
+
+ return (ISC_R_SUCCESS);
+}
+
+static isc_result_t
+fctx_create(dns_resolver_t *res, dns_name_t *name, dns_rdatatype_t type,
+ dns_name_t *domain, dns_rdataset_t *nameservers,
+ unsigned int options, unsigned int bucketnum, fetchctx_t **fctxp)
+{
+ fetchctx_t *fctx;
+ isc_result_t result = ISC_R_SUCCESS;
+ isc_result_t iresult;
+ isc_interval_t interval;
+ dns_fixedname_t qdomain;
+ unsigned int findoptions = 0;
+ char buf[DNS_NAME_FORMATSIZE + DNS_RDATATYPE_FORMATSIZE];
+ char typebuf[DNS_RDATATYPE_FORMATSIZE];
+ dns_name_t suffix;
+
+ /*
+ * Caller must be holding the lock for bucket number 'bucketnum'.
+ */
+ REQUIRE(fctxp != NULL && *fctxp == NULL);
+
+ fctx = isc_mem_get(res->mctx, sizeof(*fctx));
+ if (fctx == NULL)
+ return (ISC_R_NOMEMORY);
+ dns_name_format(name, buf, sizeof(buf));
+ dns_rdatatype_format(type, typebuf, sizeof(typebuf));
+ strcat(buf, "/"); /* checked */
+ strcat(buf, typebuf); /* checked */
+ fctx->info = isc_mem_strdup(res->mctx, buf);
+ if (fctx->info == NULL)
+ goto cleanup_fetch;
+ FCTXTRACE("create");
+ dns_name_init(&fctx->name, NULL);
+ result = dns_name_dup(name, res->mctx, &fctx->name);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_info;
+ dns_name_init(&fctx->domain, NULL);
+ dns_rdataset_init(&fctx->nameservers);
+
+ fctx->type = type;
+ fctx->options = options;
+ /*
+ * Note! We do not attach to the task. We are relying on the
+ * resolver to ensure that this task doesn't go away while we are
+ * using it.
+ */
+ fctx->res = res;
+ fctx->references = 0;
+ fctx->bucketnum = bucketnum;
+ fctx->state = fetchstate_init;
+ fctx->want_shutdown = ISC_FALSE;
+ fctx->cloned = ISC_FALSE;
+ ISC_LIST_INIT(fctx->queries);
+ ISC_LIST_INIT(fctx->finds);
+ ISC_LIST_INIT(fctx->altfinds);
+ ISC_LIST_INIT(fctx->forwaddrs);
+ ISC_LIST_INIT(fctx->altaddrs);
+ ISC_LIST_INIT(fctx->forwarders);
+ fctx->fwdpolicy = dns_fwdpolicy_none;
+ ISC_LIST_INIT(fctx->bad);
+ ISC_LIST_INIT(fctx->validators);
+ fctx->find = NULL;
+ fctx->altfind = NULL;
+ fctx->pending = 0;
+ fctx->restarts = 0;
+ fctx->timeouts = 0;
+ fctx->attributes = 0;
+
+ dns_name_init(&fctx->nsname, NULL);
+ fctx->nsfetch = NULL;
+ dns_rdataset_init(&fctx->nsrrset);
+
+ if (domain == NULL) {
+ dns_forwarders_t *forwarders = NULL;
+ unsigned int labels;
+
+ /*
+ * DS records are found in the parent server.
+ * Strip label to get the correct forwarder (if any).
+ */
+ if (fctx->type == dns_rdatatype_ds &&
+ dns_name_countlabels(name) > 1) {
+ dns_name_init(&suffix, NULL);
+ labels = dns_name_countlabels(name);
+ dns_name_getlabelsequence(name, 1, labels - 1, &suffix);
+ name = &suffix;
+ }
+ result = dns_fwdtable_find(fctx->res->view->fwdtable, name,
+ &forwarders);
+ if (result == ISC_R_SUCCESS)
+ fctx->fwdpolicy = forwarders->fwdpolicy;
+
+ if (fctx->fwdpolicy != dns_fwdpolicy_only) {
+ /*
+ * The caller didn't supply a query domain and
+ * nameservers, and we're not in forward-only mode,
+ * so find the best nameservers to use.
+ */
+ if (dns_rdatatype_atparent(type))
+ findoptions |= DNS_DBFIND_NOEXACT;
+ dns_fixedname_init(&qdomain);
+ result = dns_view_findzonecut(res->view, name,
+ dns_fixedname_name(&qdomain), 0,
+ findoptions, ISC_TRUE,
+ &fctx->nameservers,
+ NULL);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_name;
+ result = dns_name_dup(dns_fixedname_name(&qdomain),
+ res->mctx, &fctx->domain);
+ if (result != ISC_R_SUCCESS) {
+ dns_rdataset_disassociate(&fctx->nameservers);
+ goto cleanup_name;
+ }
+ } else {
+ /*
+ * We're in forward-only mode. Set the query domain
+ * to ".".
+ */
+ result = dns_name_dup(dns_rootname, res->mctx,
+ &fctx->domain);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_name;
+ }
+ } else {
+ result = dns_name_dup(domain, res->mctx, &fctx->domain);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_name;
+ dns_rdataset_clone(nameservers, &fctx->nameservers);
+ }
+
+ INSIST(dns_name_issubdomain(&fctx->name, &fctx->domain));
+
+ fctx->qmessage = NULL;
+ result = dns_message_create(res->mctx, DNS_MESSAGE_INTENTRENDER,
+ &fctx->qmessage);
+
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_domain;
+
+ fctx->rmessage = NULL;
+ result = dns_message_create(res->mctx, DNS_MESSAGE_INTENTPARSE,
+ &fctx->rmessage);
+
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_qmessage;
+
+ /*
+ * Compute an expiration time for the entire fetch.
+ */
+ isc_interval_set(&interval, 30, 0); /* XXXRTH constant */
+ iresult = isc_time_nowplusinterval(&fctx->expires, &interval);
+ if (iresult != ISC_R_SUCCESS) {
+ UNEXPECTED_ERROR(__FILE__, __LINE__,
+ "isc_time_nowplusinterval: %s",
+ isc_result_totext(iresult));
+ result = ISC_R_UNEXPECTED;
+ goto cleanup_rmessage;
+ }
+
+ /*
+ * Default retry interval initialization. We set the interval now
+ * mostly so it won't be uninitialized. It will be set to the
+ * correct value before a query is issued.
+ */
+ isc_interval_set(&fctx->interval, 2, 0);
+
+ /*
+ * Create an inactive timer. It will be made active when the fetch
+ * is actually started.
+ */
+ fctx->timer = NULL;
+ iresult = isc_timer_create(res->timermgr, isc_timertype_inactive,
+ NULL, NULL,
+ res->buckets[bucketnum].task, fctx_timeout,
+ fctx, &fctx->timer);
+ if (iresult != ISC_R_SUCCESS) {
+ UNEXPECTED_ERROR(__FILE__, __LINE__,
+ "isc_timer_create: %s",
+ isc_result_totext(iresult));
+ result = ISC_R_UNEXPECTED;
+ goto cleanup_rmessage;
+ }
+
+ /*
+ * Attach to the view's cache and adb.
+ */
+ fctx->cache = NULL;
+ dns_db_attach(res->view->cachedb, &fctx->cache);
+ fctx->adb = NULL;
+ dns_adb_attach(res->view->adb, &fctx->adb);
+
+ ISC_LIST_INIT(fctx->events);
+ ISC_LINK_INIT(fctx, link);
+ fctx->magic = FCTX_MAGIC;
+
+ ISC_LIST_APPEND(res->buckets[bucketnum].fctxs, fctx, link);
+
+ LOCK(&res->nlock);
+ res->nfctx++;
+ UNLOCK(&res->nlock);
+
+ *fctxp = fctx;
+
+ return (ISC_R_SUCCESS);
+
+ cleanup_rmessage:
+ dns_message_destroy(&fctx->rmessage);
+
+ cleanup_qmessage:
+ dns_message_destroy(&fctx->qmessage);
+
+ cleanup_domain:
+ if (dns_name_countlabels(&fctx->domain) > 0)
+ dns_name_free(&fctx->domain, res->mctx);
+ if (dns_rdataset_isassociated(&fctx->nameservers))
+ dns_rdataset_disassociate(&fctx->nameservers);
+
+ cleanup_name:
+ dns_name_free(&fctx->name, res->mctx);
+
+ cleanup_info:
+ isc_mem_free(res->mctx, fctx->info);
+
+ cleanup_fetch:
+ isc_mem_put(res->mctx, fctx, sizeof(*fctx));
+
+ return (result);
+}
+
+/*
+ * Handle Responses
+ */
+static inline isc_boolean_t
+is_lame(fetchctx_t *fctx) {
+ dns_message_t *message = fctx->rmessage;
+ dns_name_t *name;
+ dns_rdataset_t *rdataset;
+ isc_result_t result;
+
+ if (message->rcode != dns_rcode_noerror &&
+ message->rcode != dns_rcode_nxdomain)
+ return (ISC_FALSE);
+
+ if (message->counts[DNS_SECTION_ANSWER] != 0)
+ return (ISC_FALSE);
+
+ if (message->counts[DNS_SECTION_AUTHORITY] == 0)
+ return (ISC_FALSE);
+
+ result = dns_message_firstname(message, DNS_SECTION_AUTHORITY);
+ while (result == ISC_R_SUCCESS) {
+ name = NULL;
+ dns_message_currentname(message, DNS_SECTION_AUTHORITY, &name);
+ for (rdataset = ISC_LIST_HEAD(name->list);
+ rdataset != NULL;
+ rdataset = ISC_LIST_NEXT(rdataset, link)) {
+ dns_namereln_t namereln;
+ int order;
+ unsigned int labels;
+ if (rdataset->type != dns_rdatatype_ns)
+ continue;
+ namereln = dns_name_fullcompare(name, &fctx->domain,
+ &order, &labels);
+ if (namereln == dns_namereln_equal &&
+ (message->flags & DNS_MESSAGEFLAG_AA) != 0)
+ return (ISC_FALSE);
+ if (namereln == dns_namereln_subdomain)
+ return (ISC_FALSE);
+ return (ISC_TRUE);
+ }
+ result = dns_message_nextname(message, DNS_SECTION_AUTHORITY);
+ }
+
+ return (ISC_FALSE);
+}
+
+static inline void
+log_lame(fetchctx_t *fctx, dns_adbaddrinfo_t *addrinfo) {
+ char namebuf[DNS_NAME_FORMATSIZE];
+ char domainbuf[DNS_NAME_FORMATSIZE];
+ char addrbuf[ISC_SOCKADDR_FORMATSIZE];
+
+ dns_name_format(&fctx->name, namebuf, sizeof(namebuf));
+ dns_name_format(&fctx->domain, domainbuf, sizeof(domainbuf));
+ isc_sockaddr_format(&addrinfo->sockaddr, addrbuf, sizeof(addrbuf));
+ isc_log_write(dns_lctx, DNS_LOGCATEGORY_LAME_SERVERS,
+ DNS_LOGMODULE_RESOLVER, ISC_LOG_INFO,
+ "lame server resolving '%s' (in '%s'?): %s",
+ namebuf, domainbuf, addrbuf);
+}
+
+static inline isc_result_t
+same_question(fetchctx_t *fctx) {
+ isc_result_t result;
+ dns_message_t *message = fctx->rmessage;
+ dns_name_t *name;
+ dns_rdataset_t *rdataset;
+
+ /*
+ * Caller must be holding the fctx lock.
+ */
+
+ /*
+ * XXXRTH Currently we support only one question.
+ */
+ if (message->counts[DNS_SECTION_QUESTION] != 1)
+ return (DNS_R_FORMERR);
+
+ result = dns_message_firstname(message, DNS_SECTION_QUESTION);
+ if (result != ISC_R_SUCCESS)
+ return (result);
+ name = NULL;
+ dns_message_currentname(message, DNS_SECTION_QUESTION, &name);
+ rdataset = ISC_LIST_HEAD(name->list);
+ INSIST(rdataset != NULL);
+ INSIST(ISC_LIST_NEXT(rdataset, link) == NULL);
+ if (fctx->type != rdataset->type ||
+ fctx->res->rdclass != rdataset->rdclass ||
+ !dns_name_equal(&fctx->name, name))
+ return (DNS_R_FORMERR);
+
+ return (ISC_R_SUCCESS);
+}
+
+static void
+clone_results(fetchctx_t *fctx) {
+ dns_fetchevent_t *event, *hevent;
+ isc_result_t result;
+ dns_name_t *name, *hname;
+
+ FCTXTRACE("clone_results");
+
+ /*
+ * Set up any other events to have the same data as the first
+ * event.
+ *
+ * Caller must be holding the appropriate lock.
+ */
+
+ fctx->cloned = ISC_TRUE;
+ hevent = ISC_LIST_HEAD(fctx->events);
+ if (hevent == NULL)
+ return;
+ hname = dns_fixedname_name(&hevent->foundname);
+ for (event = ISC_LIST_NEXT(hevent, ev_link);
+ event != NULL;
+ event = ISC_LIST_NEXT(event, ev_link)) {
+ name = dns_fixedname_name(&event->foundname);
+ result = dns_name_copy(hname, name, NULL);
+ if (result != ISC_R_SUCCESS)
+ event->result = result;
+ else
+ event->result = hevent->result;
+ dns_db_attach(hevent->db, &event->db);
+ dns_db_attachnode(hevent->db, hevent->node, &event->node);
+ INSIST(hevent->rdataset != NULL);
+ INSIST(event->rdataset != NULL);
+ if (dns_rdataset_isassociated(hevent->rdataset))
+ dns_rdataset_clone(hevent->rdataset, event->rdataset);
+ INSIST(! (hevent->sigrdataset == NULL &&
+ event->sigrdataset != NULL));
+ if (hevent->sigrdataset != NULL &&
+ dns_rdataset_isassociated(hevent->sigrdataset) &&
+ event->sigrdataset != NULL)
+ dns_rdataset_clone(hevent->sigrdataset,
+ event->sigrdataset);
+ }
+}
+
+#define CACHE(r) (((r)->attributes & DNS_RDATASETATTR_CACHE) != 0)
+#define ANSWER(r) (((r)->attributes & DNS_RDATASETATTR_ANSWER) != 0)
+#define ANSWERSIG(r) (((r)->attributes & DNS_RDATASETATTR_ANSWERSIG) != 0)
+#define EXTERNAL(r) (((r)->attributes & DNS_RDATASETATTR_EXTERNAL) != 0)
+#define CHAINING(r) (((r)->attributes & DNS_RDATASETATTR_CHAINING) != 0)
+#define CHASE(r) (((r)->attributes & DNS_RDATASETATTR_CHASE) != 0)
+#define CHECKNAMES(r) (((r)->attributes & DNS_RDATASETATTR_CHECKNAMES) != 0)
+
+
+/*
+ * Destroy '*fctx' if it is ready to be destroyed (i.e., if it has
+ * no references and is no longer waiting for any events). If this
+ * was the last fctx in the resolver, destroy the resolver.
+ *
+ * Requires:
+ * '*fctx' is shutting down.
+ */
+static void
+maybe_destroy(fetchctx_t *fctx) {
+ unsigned int bucketnum;
+ isc_boolean_t bucket_empty = ISC_FALSE;
+ dns_resolver_t *res = fctx->res;
+
+ REQUIRE(SHUTTINGDOWN(fctx));
+
+ if (fctx->pending != 0 || !ISC_LIST_EMPTY(fctx->validators))
+ return;
+
+ bucketnum = fctx->bucketnum;
+ LOCK(&res->buckets[bucketnum].lock);
+ if (fctx->references == 0)
+ bucket_empty = fctx_destroy(fctx);
+ UNLOCK(&res->buckets[bucketnum].lock);
+
+ if (bucket_empty)
+ empty_bucket(res);
+}
+
+/*
+ * The validator has finished.
+ */
+static void
+validated(isc_task_t *task, isc_event_t *event) {
+ isc_result_t result = ISC_R_SUCCESS;
+ isc_result_t eresult = ISC_R_SUCCESS;
+ isc_stdtime_t now;
+ fetchctx_t *fctx;
+ dns_validatorevent_t *vevent;
+ dns_fetchevent_t *hevent;
+ dns_rdataset_t *ardataset = NULL;
+ dns_rdataset_t *asigrdataset = NULL;
+ dns_dbnode_t *node = NULL;
+ isc_boolean_t negative;
+ isc_boolean_t chaining;
+ isc_boolean_t sentresponse;
+ isc_uint32_t ttl;
+ dns_dbnode_t *nsnode = NULL;
+ dns_name_t *name;
+ dns_rdataset_t *rdataset;
+ dns_rdataset_t *sigrdataset;
+
+ UNUSED(task); /* for now */
+
+ REQUIRE(event->ev_type == DNS_EVENT_VALIDATORDONE);
+ fctx = event->ev_arg;
+ REQUIRE(VALID_FCTX(fctx));
+ REQUIRE(!ISC_LIST_EMPTY(fctx->validators));
+
+ vevent = (dns_validatorevent_t *)event;
+
+ FCTXTRACE("received validation completion event");
+
+ ISC_LIST_UNLINK(fctx->validators, vevent->validator, link);
+
+ /*
+ * Destroy the validator early so that we can
+ * destroy the fctx if necessary.
+ */
+ dns_validator_destroy(&vevent->validator);
+
+ negative = ISC_TF(vevent->rdataset == NULL);
+
+ sentresponse = ISC_TF((fctx->options & DNS_FETCHOPT_NOVALIDATE) != 0);
+
+ /*
+ * If shutting down, ignore the results. Check to see if we're
+ * done waiting for validator completions and ADB pending events; if
+ * so, destroy the fctx.
+ */
+ if (SHUTTINGDOWN(fctx) && !sentresponse) {
+ maybe_destroy(fctx);
+ goto cleanup_event;
+ }
+
+ /*
+ * If chaining, we need to make sure that the right result code is
+ * returned, and that the rdatasets are bound.
+ */
+ if (vevent->result == ISC_R_SUCCESS &&
+ !negative &&
+ vevent->rdataset != NULL &&
+ CHAINING(vevent->rdataset))
+ {
+ if (vevent->rdataset->type == dns_rdatatype_cname)
+ eresult = DNS_R_CNAME;
+ else {
+ INSIST(vevent->rdataset->type == dns_rdatatype_dname);
+ eresult = DNS_R_DNAME;
+ }
+ chaining = ISC_TRUE;
+ } else
+ chaining = ISC_FALSE;
+
+ /*
+ * Either we're not shutting down, or we are shutting down but want
+ * to cache the result anyway (if this was a validation started by
+ * a query with cd set)
+ */
+
+ hevent = ISC_LIST_HEAD(fctx->events);
+ if (hevent != NULL) {
+ if (!negative && !chaining &&
+ (fctx->type == dns_rdatatype_any ||
+ fctx->type == dns_rdatatype_rrsig)) {
+ /*
+ * Don't bind rdatasets; the caller
+ * will iterate the node.
+ */
+ } else {
+ ardataset = hevent->rdataset;
+ asigrdataset = hevent->sigrdataset;
+ }
+ }
+
+ if (vevent->result != ISC_R_SUCCESS) {
+ FCTXTRACE("validation failed");
+ if (vevent->rdataset != NULL) {
+ result = dns_db_findnode(fctx->cache, vevent->name,
+ ISC_TRUE, &node);
+ if (result != ISC_R_SUCCESS)
+ goto noanswer_response;
+ (void)dns_db_deleterdataset(fctx->cache, node, NULL,
+ vevent->type, 0);
+ if (vevent->sigrdataset != NULL)
+ (void)dns_db_deleterdataset(fctx->cache,
+ node, NULL,
+ dns_rdatatype_rrsig,
+ vevent->type);
+ }
+ result = vevent->result;
+ goto noanswer_response;
+ }
+
+ isc_stdtime_get(&now);
+
+ if (negative) {
+ dns_rdatatype_t covers;
+ FCTXTRACE("nonexistence validation OK");
+
+ if (fctx->rmessage->rcode == dns_rcode_nxdomain)
+ covers = dns_rdatatype_any;
+ else
+ covers = fctx->type;
+
+ result = dns_db_findnode(fctx->cache, vevent->name, ISC_TRUE,
+ &node);
+ if (result != ISC_R_SUCCESS)
+ goto noanswer_response;
+
+ /*
+ * If we are asking for a SOA record set the cache time
+ * to zero to facilitate locating the containing zone of
+ * a arbitary zone.
+ */
+ ttl = fctx->res->view->maxncachettl;
+ if (fctx->type == dns_rdatatype_soa &&
+ covers == dns_rdatatype_any)
+ ttl = 0;
+
+ result = ncache_adderesult(fctx->rmessage, fctx->cache, node,
+ covers, now, ttl,
+ ardataset, &eresult);
+ if (result != ISC_R_SUCCESS)
+ goto noanswer_response;
+ goto answer_response;
+ }
+
+ FCTXTRACE("validation OK");
+
+ if (vevent->proofs[DNS_VALIDATOR_NOQNAMEPROOF] != NULL) {
+
+ result = dns_rdataset_addnoqname(vevent->rdataset,
+ vevent->proofs[DNS_VALIDATOR_NOQNAMEPROOF]);
+ RUNTIME_CHECK(result == ISC_R_SUCCESS);
+ vevent->sigrdataset->ttl = vevent->rdataset->ttl;
+ }
+
+ /*
+ * The data was already cached as pending data.
+ * Re-cache it as secure and bind the cached
+ * rdatasets to the first event on the fetch
+ * event list.
+ */
+ result = dns_db_findnode(fctx->cache, vevent->name, ISC_TRUE, &node);
+ if (result != ISC_R_SUCCESS)
+ goto noanswer_response;
+
+ result = dns_db_addrdataset(fctx->cache, node, NULL, now,
+ vevent->rdataset, 0, ardataset);
+ if (result != ISC_R_SUCCESS &&
+ result != DNS_R_UNCHANGED)
+ goto noanswer_response;
+ if (vevent->sigrdataset != NULL) {
+ result = dns_db_addrdataset(fctx->cache, node, NULL, now,
+ vevent->sigrdataset, 0,
+ asigrdataset);
+ if (result != ISC_R_SUCCESS &&
+ result != DNS_R_UNCHANGED)
+ goto noanswer_response;
+ }
+
+ if (sentresponse) {
+ /*
+ * If we only deferred the destroy because we wanted to cache
+ * the data, destroy now.
+ */
+ if (SHUTTINGDOWN(fctx))
+ maybe_destroy(fctx);
+
+ goto cleanup_event;
+ }
+
+ if (!ISC_LIST_EMPTY(fctx->validators)) {
+ INSIST(!negative);
+ INSIST(fctx->type == dns_rdatatype_any ||
+ fctx->type == dns_rdatatype_rrsig);
+ /*
+ * Don't send a response yet - we have
+ * more rdatasets that still need to
+ * be validated.
+ */
+ goto cleanup_event;
+ }
+
+ answer_response:
+ /*
+ * Cache any NS/NSEC records that happened to be validated.
+ */
+ result = dns_message_firstname(fctx->rmessage, DNS_SECTION_AUTHORITY);
+ while (result == ISC_R_SUCCESS) {
+ name = NULL;
+ dns_message_currentname(fctx->rmessage, DNS_SECTION_AUTHORITY,
+ &name);
+ for (rdataset = ISC_LIST_HEAD(name->list);
+ rdataset != NULL;
+ rdataset = ISC_LIST_NEXT(rdataset, link)) {
+ if ((rdataset->type != dns_rdatatype_ns &&
+ rdataset->type != dns_rdatatype_nsec) ||
+ rdataset->trust != dns_trust_secure)
+ continue;
+ for (sigrdataset = ISC_LIST_HEAD(name->list);
+ sigrdataset != NULL;
+ sigrdataset = ISC_LIST_NEXT(sigrdataset, link)) {
+ if (sigrdataset->type != dns_rdatatype_rrsig ||
+ sigrdataset->covers != rdataset->type)
+ continue;
+ break;
+ }
+ if (sigrdataset == NULL ||
+ sigrdataset->trust != dns_trust_secure)
+ continue;
+ result = dns_db_findnode(fctx->cache, name, ISC_TRUE,
+ &nsnode);
+ if (result != ISC_R_SUCCESS)
+ continue;
+
+ result = dns_db_addrdataset(fctx->cache, nsnode, NULL,
+ now, rdataset, 0, NULL);
+ if (result == ISC_R_SUCCESS)
+ result = dns_db_addrdataset(fctx->cache, nsnode,
+ NULL, now,
+ sigrdataset, 0,
+ NULL);
+ dns_db_detachnode(fctx->cache, &nsnode);
+ }
+ result = dns_message_nextname(fctx->rmessage,
+ DNS_SECTION_AUTHORITY);
+ }
+
+ result = ISC_R_SUCCESS;
+
+ /*
+ * Respond with an answer, positive or negative,
+ * as opposed to an error. 'node' must be non-NULL.
+ */
+
+ fctx->attributes |= FCTX_ATTR_HAVEANSWER;
+
+ if (hevent != NULL) {
+ hevent->result = eresult;
+ RUNTIME_CHECK(dns_name_copy(vevent->name,
+ dns_fixedname_name(&hevent->foundname), NULL)
+ == ISC_R_SUCCESS);
+ dns_db_attach(fctx->cache, &hevent->db);
+ hevent->node = node;
+ node = NULL;
+ clone_results(fctx);
+ }
+
+ noanswer_response:
+ if (node != NULL)
+ dns_db_detachnode(fctx->cache, &node);
+
+ fctx_done(fctx, result);
+
+ cleanup_event:
+ isc_event_free(&event);
+}
+
+static inline isc_result_t
+cache_name(fetchctx_t *fctx, dns_name_t *name, isc_stdtime_t now) {
+ dns_rdataset_t *rdataset, *sigrdataset;
+ dns_rdataset_t *addedrdataset, *ardataset, *asigrdataset;
+ dns_rdataset_t *valrdataset = NULL, *valsigrdataset = NULL;
+ dns_dbnode_t *node, **anodep;
+ dns_db_t **adbp;
+ dns_name_t *aname;
+ dns_resolver_t *res;
+ isc_boolean_t need_validation, secure_domain, have_answer;
+ isc_result_t result, eresult;
+ dns_fetchevent_t *event;
+ unsigned int options;
+ isc_task_t *task;
+ dns_validator_t *validator;
+ isc_boolean_t fail;
+
+ /*
+ * The appropriate bucket lock must be held.
+ */
+
+ res = fctx->res;
+ need_validation = ISC_FALSE;
+ secure_domain = ISC_FALSE;
+ have_answer = ISC_FALSE;
+ eresult = ISC_R_SUCCESS;
+ task = res->buckets[fctx->bucketnum].task;
+
+ /*
+ * Is DNSSEC validation required for this name?
+ */
+ result = dns_keytable_issecuredomain(res->view->secroots, name,
+ &secure_domain);
+ if (result != ISC_R_SUCCESS)
+ return (result);
+
+ if (res->view->dlv != NULL)
+ secure_domain = ISC_TRUE;
+
+ if ((fctx->options & DNS_FETCHOPT_NOVALIDATE) != 0)
+ need_validation = ISC_FALSE;
+ else
+ need_validation = secure_domain;
+
+ adbp = NULL;
+ aname = NULL;
+ anodep = NULL;
+ ardataset = NULL;
+ asigrdataset = NULL;
+ event = NULL;
+ if ((name->attributes & DNS_NAMEATTR_ANSWER) != 0 &&
+ !need_validation) {
+ have_answer = ISC_TRUE;
+ event = ISC_LIST_HEAD(fctx->events);
+ if (event != NULL) {
+ adbp = &event->db;
+ aname = dns_fixedname_name(&event->foundname);
+ result = dns_name_copy(name, aname, NULL);
+ if (result != ISC_R_SUCCESS)
+ return (result);
+ anodep = &event->node;
+ /*
+ * If this is an ANY or SIG query, we're not going
+ * to return any rdatasets, unless we encountered
+ * a CNAME or DNAME as "the answer". In this case,
+ * we're going to return DNS_R_CNAME or DNS_R_DNAME
+ * and we must set up the rdatasets.
+ */
+ if ((fctx->type != dns_rdatatype_any &&
+ fctx->type != dns_rdatatype_rrsig) ||
+ (name->attributes & DNS_NAMEATTR_CHAINING) != 0) {
+ ardataset = event->rdataset;
+ asigrdataset = event->sigrdataset;
+ }
+ }
+ }
+
+ /*
+ * Find or create the cache node.
+ */
+ node = NULL;
+ result = dns_db_findnode(fctx->cache, name, ISC_TRUE, &node);
+ if (result != ISC_R_SUCCESS)
+ return (result);
+
+ /*
+ * Cache or validate each cacheable rdataset.
+ */
+ fail = (fctx->res->options & DNS_RESOLVER_CHECKNAMESFAIL) != 0;
+ for (rdataset = ISC_LIST_HEAD(name->list);
+ rdataset != NULL;
+ rdataset = ISC_LIST_NEXT(rdataset, link)) {
+ if (!CACHE(rdataset))
+ continue;
+ if (CHECKNAMES(rdataset)) {
+ char namebuf[DNS_NAME_FORMATSIZE];
+ char typebuf[DNS_RDATATYPE_FORMATSIZE];
+ char classbuf[DNS_RDATATYPE_FORMATSIZE];
+
+ dns_name_format(name, namebuf, sizeof(namebuf));
+ dns_rdatatype_format(rdataset->type, typebuf,
+ sizeof(typebuf));
+ dns_rdataclass_format(rdataset->rdclass, classbuf,
+ sizeof(classbuf));
+ isc_log_write(dns_lctx, DNS_LOGCATEGORY_RESOLVER,
+ DNS_LOGMODULE_RESOLVER, ISC_LOG_NOTICE,
+ "check-names %s %s/%s/%s",
+ fail ? "failure" : "warning",
+ namebuf, typebuf, classbuf);
+ if (fail) {
+ if (ANSWER(rdataset))
+ return (DNS_R_BADNAME);
+ continue;
+ }
+ }
+
+ /*
+ * Enforce the configure maximum cache TTL.
+ */
+ if (rdataset->ttl > res->view->maxcachettl)
+ rdataset->ttl = res->view->maxcachettl;
+
+ /*
+ * If this rrset is in a secure domain, do DNSSEC validation
+ * for it, unless it is glue.
+ */
+ if (secure_domain && rdataset->trust != dns_trust_glue) {
+ /*
+ * SIGs are validated as part of validating the
+ * type they cover.
+ */
+ if (rdataset->type == dns_rdatatype_rrsig)
+ continue;
+ /*
+ * Find the SIG for this rdataset, if we have it.
+ */
+ for (sigrdataset = ISC_LIST_HEAD(name->list);
+ sigrdataset != NULL;
+ sigrdataset = ISC_LIST_NEXT(sigrdataset, link)) {
+ if (sigrdataset->type == dns_rdatatype_rrsig &&
+ sigrdataset->covers == rdataset->type)
+ break;
+ }
+ if (sigrdataset == NULL) {
+ if (!ANSWER(rdataset) && need_validation) {
+ /*
+ * Ignore non-answer rdatasets that
+ * are missing signatures.
+ */
+ continue;
+ }
+ }
+
+ /*
+ * Normalize the rdataset and sigrdataset TTLs.
+ */
+ if (sigrdataset != NULL) {
+ rdataset->ttl = ISC_MIN(rdataset->ttl,
+ sigrdataset->ttl);
+ sigrdataset->ttl = rdataset->ttl;
+ }
+
+ /*
+ * Cache this rdataset/sigrdataset pair as
+ * pending data.
+ */
+ rdataset->trust = dns_trust_pending;
+ if (sigrdataset != NULL)
+ sigrdataset->trust = dns_trust_pending;
+ if (!need_validation)
+ addedrdataset = ardataset;
+ else
+ addedrdataset = NULL;
+ result = dns_db_addrdataset(fctx->cache, node, NULL,
+ now, rdataset, 0,
+ addedrdataset);
+ if (result == DNS_R_UNCHANGED)
+ result = ISC_R_SUCCESS;
+ if (result != ISC_R_SUCCESS)
+ break;
+ if (sigrdataset != NULL) {
+ if (!need_validation)
+ addedrdataset = asigrdataset;
+ else
+ addedrdataset = NULL;
+ result = dns_db_addrdataset(fctx->cache,
+ node, NULL, now,
+ sigrdataset, 0,
+ addedrdataset);
+ if (result == DNS_R_UNCHANGED)
+ result = ISC_R_SUCCESS;
+ if (result != ISC_R_SUCCESS)
+ break;
+ } else if (!ANSWER(rdataset))
+ continue;
+
+ if (ANSWER(rdataset) && need_validation) {
+ if (fctx->type != dns_rdatatype_any &&
+ fctx->type != dns_rdatatype_rrsig) {
+ /*
+ * This is The Answer. We will
+ * validate it, but first we cache
+ * the rest of the response - it may
+ * contain useful keys.
+ */
+ INSIST(valrdataset == NULL &&
+ valsigrdataset == NULL);
+ valrdataset = rdataset;
+ valsigrdataset = sigrdataset;
+ } else {
+ /*
+ * This is one of (potentially)
+ * multiple answers to an ANY
+ * or SIG query. To keep things
+ * simple, we just start the
+ * validator right away rather
+ * than caching first and
+ * having to remember which
+ * rdatasets needed validation.
+ */
+ validator = NULL;
+ result = dns_validator_create(
+ res->view,
+ name,
+ rdataset->type,
+ rdataset,
+ sigrdataset,
+ fctx->rmessage,
+ 0,
+ task,
+ validated,
+ fctx,
+ &validator);
+ if (result == ISC_R_SUCCESS)
+ ISC_LIST_APPEND(
+ fctx->validators,
+ validator, link);
+ }
+ }
+ } else if (!EXTERNAL(rdataset)) {
+ /*
+ * It's OK to cache this rdataset now.
+ */
+ if (ANSWER(rdataset))
+ addedrdataset = ardataset;
+ else if (ANSWERSIG(rdataset))
+ addedrdataset = asigrdataset;
+ else
+ addedrdataset = NULL;
+ if (CHAINING(rdataset)) {
+ if (rdataset->type == dns_rdatatype_cname)
+ eresult = DNS_R_CNAME;
+ else {
+ INSIST(rdataset->type ==
+ dns_rdatatype_dname);
+ eresult = DNS_R_DNAME;
+ }
+ }
+ if (rdataset->trust == dns_trust_glue &&
+ (rdataset->type == dns_rdatatype_ns ||
+ (rdataset->type == dns_rdatatype_rrsig &&
+ rdataset->covers == dns_rdatatype_ns))) {
+ /*
+ * If the trust level is 'dns_trust_glue'
+ * then we are adding data from a referral
+ * we got while executing the search algorithm.
+ * New referral data always takes precedence
+ * over the existing cache contents.
+ */
+ options = DNS_DBADD_FORCE;
+ } else
+ options = 0;
+ /*
+ * Now we can add the rdataset.
+ */
+ result = dns_db_addrdataset(fctx->cache,
+ node, NULL, now,
+ rdataset,
+ options,
+ addedrdataset);
+ if (result == DNS_R_UNCHANGED) {
+ if (ANSWER(rdataset) &&
+ ardataset != NULL &&
+ ardataset->type == 0) {
+ /*
+ * The answer in the cache is better
+ * than the answer we found, and is
+ * a negative cache entry, so we
+ * must set eresult appropriately.
+ */
+ if (NXDOMAIN(ardataset))
+ eresult =
+ DNS_R_NCACHENXDOMAIN;
+ else
+ eresult =
+ DNS_R_NCACHENXRRSET;
+ }
+ result = ISC_R_SUCCESS;
+ } else if (result != ISC_R_SUCCESS)
+ break;
+ }
+ }
+
+ if (valrdataset != NULL) {
+ validator = NULL;
+ result = dns_validator_create(res->view,
+ name,
+ fctx->type,
+ valrdataset,
+ valsigrdataset,
+ fctx->rmessage,
+ 0,
+ task,
+ validated,
+ fctx,
+ &validator);
+ if (result == ISC_R_SUCCESS)
+ ISC_LIST_APPEND(fctx->validators, validator, link);
+ }
+
+ if (result == ISC_R_SUCCESS && have_answer) {
+ fctx->attributes |= FCTX_ATTR_HAVEANSWER;
+ if (event != NULL) {
+ event->result = eresult;
+ dns_db_attach(fctx->cache, adbp);
+ *anodep = node;
+ node = NULL;
+ clone_results(fctx);
+ }
+ }
+
+ if (node != NULL)
+ dns_db_detachnode(fctx->cache, &node);
+
+ return (result);
+}
+
+static inline isc_result_t
+cache_message(fetchctx_t *fctx, isc_stdtime_t now) {
+ isc_result_t result;
+ dns_section_t section;
+ dns_name_t *name;
+
+ FCTXTRACE("cache_message");
+
+ fctx->attributes &= ~FCTX_ATTR_WANTCACHE;
+
+ LOCK(&fctx->res->buckets[fctx->bucketnum].lock);
+
+ for (section = DNS_SECTION_ANSWER;
+ section <= DNS_SECTION_ADDITIONAL;
+ section++) {
+ result = dns_message_firstname(fctx->rmessage, section);
+ while (result == ISC_R_SUCCESS) {
+ name = NULL;
+ dns_message_currentname(fctx->rmessage, section,
+ &name);
+ if ((name->attributes & DNS_NAMEATTR_CACHE) != 0) {
+ result = cache_name(fctx, name, now);
+ if (result != ISC_R_SUCCESS)
+ break;
+ }
+ result = dns_message_nextname(fctx->rmessage, section);
+ }
+ if (result != ISC_R_NOMORE)
+ break;
+ }
+ if (result == ISC_R_NOMORE)
+ result = ISC_R_SUCCESS;
+
+ UNLOCK(&fctx->res->buckets[fctx->bucketnum].lock);
+
+ return (result);
+}
+
+/*
+ * Do what dns_ncache_add() does, and then compute an appropriate eresult.
+ */
+static isc_result_t
+ncache_adderesult(dns_message_t *message, dns_db_t *cache, dns_dbnode_t *node,
+ dns_rdatatype_t covers, isc_stdtime_t now, dns_ttl_t maxttl,
+ dns_rdataset_t *ardataset,
+ isc_result_t *eresultp)
+{
+ isc_result_t result;
+ result = dns_ncache_add(message, cache, node, covers, now,
+ maxttl, ardataset);
+ if (result == DNS_R_UNCHANGED) {
+ /*
+ * The data in the cache are better than the negative cache
+ * entry we're trying to add.
+ */
+ if (ardataset != NULL && ardataset->type == 0) {
+ /*
+ * The cache data is also a negative cache
+ * entry.
+ */
+ if (NXDOMAIN(ardataset))
+ *eresultp = DNS_R_NCACHENXDOMAIN;
+ else
+ *eresultp = DNS_R_NCACHENXRRSET;
+ result = ISC_R_SUCCESS;
+ } else {
+ /*
+ * Either we don't care about the nature of the
+ * cache rdataset (because no fetch is interested
+ * in the outcome), or the cache rdataset is not
+ * a negative cache entry. Whichever case it is,
+ * we can return success.
+ *
+ * XXXRTH There's a CNAME/DNAME problem here.
+ */
+ *eresultp = ISC_R_SUCCESS;
+ result = ISC_R_SUCCESS;
+ }
+ } else if (result == ISC_R_SUCCESS) {
+ if (NXDOMAIN(ardataset))
+ *eresultp = DNS_R_NCACHENXDOMAIN;
+ else
+ *eresultp = DNS_R_NCACHENXRRSET;
+ }
+
+ return (result);
+}
+
+static inline isc_result_t
+ncache_message(fetchctx_t *fctx, dns_rdatatype_t covers, isc_stdtime_t now) {
+ isc_result_t result, eresult;
+ dns_name_t *name;
+ dns_resolver_t *res;
+ dns_db_t **adbp;
+ dns_dbnode_t *node, **anodep;
+ dns_rdataset_t *ardataset;
+ isc_boolean_t need_validation, secure_domain;
+ dns_name_t *aname;
+ dns_fetchevent_t *event;
+ isc_uint32_t ttl;
+
+ FCTXTRACE("ncache_message");
+
+ fctx->attributes &= ~FCTX_ATTR_WANTNCACHE;
+
+ res = fctx->res;
+ need_validation = ISC_FALSE;
+ secure_domain = ISC_FALSE;
+ eresult = ISC_R_SUCCESS;
+ name = &fctx->name;
+ node = NULL;
+
+ /*
+ * XXXMPA remove when we follow cnames and adjust the setting
+ * of FCTX_ATTR_WANTNCACHE in noanswer_response().
+ */
+ INSIST(fctx->rmessage->counts[DNS_SECTION_ANSWER] == 0);
+
+ /*
+ * Is DNSSEC validation required for this name?
+ */
+ result = dns_keytable_issecuredomain(res->view->secroots, name,
+ &secure_domain);
+ if (result != ISC_R_SUCCESS)
+ return (result);
+
+ if (res->view->dlv != NULL)
+ secure_domain = ISC_TRUE;
+
+ if ((fctx->options & DNS_FETCHOPT_NOVALIDATE) != 0)
+ need_validation = ISC_FALSE;
+ else
+ need_validation = secure_domain;
+
+ if (secure_domain) {
+ /*
+ * Mark all rdatasets as pending.
+ */
+ dns_rdataset_t *trdataset;
+ dns_name_t *tname;
+
+ result = dns_message_firstname(fctx->rmessage,
+ DNS_SECTION_AUTHORITY);
+ while (result == ISC_R_SUCCESS) {
+ tname = NULL;
+ dns_message_currentname(fctx->rmessage,
+ DNS_SECTION_AUTHORITY,
+ &tname);
+ for (trdataset = ISC_LIST_HEAD(tname->list);
+ trdataset != NULL;
+ trdataset = ISC_LIST_NEXT(trdataset, link))
+ trdataset->trust = dns_trust_pending;
+ result = dns_message_nextname(fctx->rmessage,
+ DNS_SECTION_AUTHORITY);
+ }
+ if (result != ISC_R_NOMORE)
+ return (result);
+
+ }
+
+ if (need_validation) {
+ /*
+ * Do negative response validation.
+ */
+ dns_validator_t *validator = NULL;
+ isc_task_t *task = res->buckets[fctx->bucketnum].task;
+
+ result = dns_validator_create(res->view, name, fctx->type,
+ NULL, NULL,
+ fctx->rmessage, 0, task,
+ validated, fctx,
+ &validator);
+ if (result != ISC_R_SUCCESS)
+ return (result);
+ ISC_LIST_APPEND(fctx->validators, validator, link);
+ /*
+ * If validation is necessary, return now. Otherwise continue
+ * to process the message, letting the validation complete
+ * in its own good time.
+ */
+ return (ISC_R_SUCCESS);
+ }
+
+ LOCK(&res->buckets[fctx->bucketnum].lock);
+
+ adbp = NULL;
+ aname = NULL;
+ anodep = NULL;
+ ardataset = NULL;
+ if (!HAVE_ANSWER(fctx)) {
+ event = ISC_LIST_HEAD(fctx->events);
+ if (event != NULL) {
+ adbp = &event->db;
+ aname = dns_fixedname_name(&event->foundname);
+ result = dns_name_copy(name, aname, NULL);
+ if (result != ISC_R_SUCCESS)
+ goto unlock;
+ anodep = &event->node;
+ ardataset = event->rdataset;
+ }
+ } else
+ event = NULL;
+
+ result = dns_db_findnode(fctx->cache, name, ISC_TRUE, &node);
+ if (result != ISC_R_SUCCESS)
+ goto unlock;
+
+ /*
+ * If we are asking for a SOA record set the cache time
+ * to zero to facilitate locating the containing zone of
+ * a arbitary zone.
+ */
+ ttl = fctx->res->view->maxncachettl;
+ if (fctx->type == dns_rdatatype_soa &&
+ covers == dns_rdatatype_any)
+ ttl = 0;
+
+ result = ncache_adderesult(fctx->rmessage, fctx->cache, node,
+ covers, now, ttl, ardataset, &eresult);
+ if (result != ISC_R_SUCCESS)
+ goto unlock;
+
+ if (!HAVE_ANSWER(fctx)) {
+ fctx->attributes |= FCTX_ATTR_HAVEANSWER;
+ if (event != NULL) {
+ event->result = eresult;
+ dns_db_attach(fctx->cache, adbp);
+ *anodep = node;
+ node = NULL;
+ clone_results(fctx);
+ }
+ }
+
+ unlock:
+ UNLOCK(&res->buckets[fctx->bucketnum].lock);
+
+ if (node != NULL)
+ dns_db_detachnode(fctx->cache, &node);
+
+ return (result);
+}
+
+static inline void
+mark_related(dns_name_t *name, dns_rdataset_t *rdataset,
+ isc_boolean_t external, isc_boolean_t gluing)
+{
+ name->attributes |= DNS_NAMEATTR_CACHE;
+ if (gluing) {
+ rdataset->trust = dns_trust_glue;
+ /*
+ * Glue with 0 TTL causes problems. We force the TTL to
+ * 1 second to prevent this.
+ */
+ if (rdataset->ttl == 0)
+ rdataset->ttl = 1;
+ } else
+ rdataset->trust = dns_trust_additional;
+ /*
+ * Avoid infinite loops by only marking new rdatasets.
+ */
+ if (!CACHE(rdataset)) {
+ name->attributes |= DNS_NAMEATTR_CHASE;
+ rdataset->attributes |= DNS_RDATASETATTR_CHASE;
+ }
+ rdataset->attributes |= DNS_RDATASETATTR_CACHE;
+ if (external)
+ rdataset->attributes |= DNS_RDATASETATTR_EXTERNAL;
+}
+
+static isc_result_t
+check_related(void *arg, dns_name_t *addname, dns_rdatatype_t type) {
+ fetchctx_t *fctx = arg;
+ isc_result_t result;
+ dns_name_t *name;
+ dns_rdataset_t *rdataset;
+ isc_boolean_t external;
+ dns_rdatatype_t rtype;
+ isc_boolean_t gluing;
+
+ REQUIRE(VALID_FCTX(fctx));
+
+ if (GLUING(fctx))
+ gluing = ISC_TRUE;
+ else
+ gluing = ISC_FALSE;
+ name = NULL;
+ rdataset = NULL;
+ result = dns_message_findname(fctx->rmessage, DNS_SECTION_ADDITIONAL,
+ addname, dns_rdatatype_any, 0, &name,
+ NULL);
+ if (result == ISC_R_SUCCESS) {
+ external = ISC_TF(!dns_name_issubdomain(name, &fctx->domain));
+ if (type == dns_rdatatype_a) {
+ for (rdataset = ISC_LIST_HEAD(name->list);
+ rdataset != NULL;
+ rdataset = ISC_LIST_NEXT(rdataset, link)) {
+ if (rdataset->type == dns_rdatatype_rrsig)
+ rtype = rdataset->covers;
+ else
+ rtype = rdataset->type;
+ if (rtype == dns_rdatatype_a ||
+ rtype == dns_rdatatype_aaaa)
+ mark_related(name, rdataset, external,
+ gluing);
+ }
+ } else {
+ result = dns_message_findtype(name, type, 0,
+ &rdataset);
+ if (result == ISC_R_SUCCESS) {
+ mark_related(name, rdataset, external, gluing);
+ /*
+ * Do we have its SIG too?
+ */
+ rdataset = NULL;
+ result = dns_message_findtype(name,
+ dns_rdatatype_rrsig,
+ type, &rdataset);
+ if (result == ISC_R_SUCCESS)
+ mark_related(name, rdataset, external,
+ gluing);
+ }
+ }
+ }
+
+ return (ISC_R_SUCCESS);
+}
+
+static void
+chase_additional(fetchctx_t *fctx) {
+ isc_boolean_t rescan;
+ dns_section_t section = DNS_SECTION_ADDITIONAL;
+ isc_result_t result;
+
+ again:
+ rescan = ISC_FALSE;
+
+ for (result = dns_message_firstname(fctx->rmessage, section);
+ result == ISC_R_SUCCESS;
+ result = dns_message_nextname(fctx->rmessage, section)) {
+ dns_name_t *name = NULL;
+ dns_rdataset_t *rdataset;
+ dns_message_currentname(fctx->rmessage, DNS_SECTION_ADDITIONAL,
+ &name);
+ if ((name->attributes & DNS_NAMEATTR_CHASE) == 0)
+ continue;
+ name->attributes &= ~DNS_NAMEATTR_CHASE;
+ for (rdataset = ISC_LIST_HEAD(name->list);
+ rdataset != NULL;
+ rdataset = ISC_LIST_NEXT(rdataset, link)) {
+ if (CHASE(rdataset)) {
+ rdataset->attributes &= ~DNS_RDATASETATTR_CHASE;
+ (void)dns_rdataset_additionaldata(rdataset,
+ check_related,
+ fctx);
+ rescan = ISC_TRUE;
+ }
+ }
+ }
+ if (rescan)
+ goto again;
+}
+
+static inline isc_result_t
+cname_target(dns_rdataset_t *rdataset, dns_name_t *tname) {
+ isc_result_t result;
+ dns_rdata_t rdata = DNS_RDATA_INIT;
+ dns_rdata_cname_t cname;
+
+ result = dns_rdataset_first(rdataset);
+ if (result != ISC_R_SUCCESS)
+ return (result);
+ dns_rdataset_current(rdataset, &rdata);
+ result = dns_rdata_tostruct(&rdata, &cname, NULL);
+ if (result != ISC_R_SUCCESS)
+ return (result);
+ dns_name_init(tname, NULL);
+ dns_name_clone(&cname.cname, tname);
+ dns_rdata_freestruct(&cname);
+
+ return (ISC_R_SUCCESS);
+}
+
+static inline isc_result_t
+dname_target(dns_rdataset_t *rdataset, dns_name_t *qname, dns_name_t *oname,
+ dns_fixedname_t *fixeddname)
+{
+ isc_result_t result;
+ dns_rdata_t rdata = DNS_RDATA_INIT;
+ unsigned int nlabels;
+ int order;
+ dns_namereln_t namereln;
+ dns_rdata_dname_t dname;
+ dns_fixedname_t prefix;
+
+ /*
+ * Get the target name of the DNAME.
+ */
+
+ result = dns_rdataset_first(rdataset);
+ if (result != ISC_R_SUCCESS)
+ return (result);
+ dns_rdataset_current(rdataset, &rdata);
+ result = dns_rdata_tostruct(&rdata, &dname, NULL);
+ if (result != ISC_R_SUCCESS)
+ return (result);
+
+ /*
+ * Get the prefix of qname.
+ */
+ namereln = dns_name_fullcompare(qname, oname, &order, &nlabels);
+ if (namereln != dns_namereln_subdomain) {
+ dns_rdata_freestruct(&dname);
+ return (DNS_R_FORMERR);
+ }
+ dns_fixedname_init(&prefix);
+ dns_name_split(qname, nlabels, dns_fixedname_name(&prefix), NULL);
+ dns_fixedname_init(fixeddname);
+ result = dns_name_concatenate(dns_fixedname_name(&prefix),
+ &dname.dname,
+ dns_fixedname_name(fixeddname), NULL);
+ dns_rdata_freestruct(&dname);
+ return (result);
+}
+
+/*
+ * Handle a no-answer response (NXDOMAIN, NXRRSET, or referral).
+ * If bind8_ns_resp is ISC_TRUE, this is a suspected BIND 8
+ * response to an NS query that should be treated as a referral
+ * even though the NS records occur in the answer section
+ * rather than the authority section.
+ */
+static isc_result_t
+noanswer_response(fetchctx_t *fctx, dns_name_t *oqname,
+ isc_boolean_t bind8_ns_resp)
+{
+ isc_result_t result;
+ dns_message_t *message;
+ dns_name_t *name, *qname, *ns_name, *soa_name, *ds_name;
+ dns_rdataset_t *rdataset, *ns_rdataset;
+ isc_boolean_t done, aa, negative_response;
+ dns_rdatatype_t type;
+ dns_section_t section =
+ bind8_ns_resp ? DNS_SECTION_ANSWER : DNS_SECTION_AUTHORITY;
+
+ FCTXTRACE("noanswer_response");
+
+ message = fctx->rmessage;
+
+ /*
+ * Setup qname.
+ */
+ if (oqname == NULL) {
+ /*
+ * We have a normal, non-chained negative response or
+ * referral.
+ */
+ if ((message->flags & DNS_MESSAGEFLAG_AA) != 0)
+ aa = ISC_TRUE;
+ else
+ aa = ISC_FALSE;
+ qname = &fctx->name;
+ } else {
+ /*
+ * We're being invoked by answer_response() after it has
+ * followed a CNAME/DNAME chain.
+ */
+ qname = oqname;
+ aa = ISC_FALSE;
+ /*
+ * If the current qname is not a subdomain of the query
+ * domain, there's no point in looking at the authority
+ * section without doing DNSSEC validation.
+ *
+ * Until we do that validation, we'll just return success
+ * in this case.
+ */
+ if (!dns_name_issubdomain(qname, &fctx->domain))
+ return (ISC_R_SUCCESS);
+ }
+
+ /*
+ * We have to figure out if this is a negative response, or a
+ * referral.
+ */
+
+ /*
+ * Sometimes we can tell if its a negative response by looking at
+ * the message header.
+ */
+ negative_response = ISC_FALSE;
+ if (message->rcode == dns_rcode_nxdomain ||
+ (message->counts[DNS_SECTION_ANSWER] == 0 &&
+ message->counts[DNS_SECTION_AUTHORITY] == 0))
+ negative_response = ISC_TRUE;
+
+ /*
+ * Process the authority section.
+ */
+ done = ISC_FALSE;
+ ns_name = NULL;
+ ns_rdataset = NULL;
+ soa_name = NULL;
+ ds_name = NULL;
+ result = dns_message_firstname(message, section);
+ while (!done && result == ISC_R_SUCCESS) {
+ name = NULL;
+ dns_message_currentname(message, section, &name);
+ if (dns_name_issubdomain(name, &fctx->domain)) {
+ /*
+ * Look for NS RRset first.
+ */
+ for (rdataset = ISC_LIST_HEAD(name->list);
+ rdataset != NULL;
+ rdataset = ISC_LIST_NEXT(rdataset, link)) {
+ type = rdataset->type;
+ if (type == dns_rdatatype_rrsig)
+ type = rdataset->covers;
+ if (((type == dns_rdatatype_ns ||
+ type == dns_rdatatype_soa) &&
+ !dns_name_issubdomain(qname, name)))
+ return (DNS_R_FORMERR);
+ if (type == dns_rdatatype_ns) {
+ /*
+ * NS or SIG NS.
+ *
+ * Only one set of NS RRs is allowed.
+ */
+ if (rdataset->type ==
+ dns_rdatatype_ns) {
+ if (ns_name != NULL &&
+ name != ns_name)
+ return (DNS_R_FORMERR);
+ ns_name = name;
+ ns_rdataset = rdataset;
+ }
+ name->attributes |=
+ DNS_NAMEATTR_CACHE;
+ rdataset->attributes |=
+ DNS_RDATASETATTR_CACHE;
+ rdataset->trust = dns_trust_glue;
+ }
+ }
+ for (rdataset = ISC_LIST_HEAD(name->list);
+ rdataset != NULL;
+ rdataset = ISC_LIST_NEXT(rdataset, link)) {
+ type = rdataset->type;
+ if (type == dns_rdatatype_rrsig)
+ type = rdataset->covers;
+ if (type == dns_rdatatype_soa ||
+ type == dns_rdatatype_nsec) {
+ /*
+ * SOA, RRSIG SOA, NSEC, or RRSIG NSEC.
+ *
+ * Only one SOA is allowed.
+ */
+ if (rdataset->type ==
+ dns_rdatatype_soa) {
+ if (soa_name != NULL &&
+ name != soa_name)
+ return (DNS_R_FORMERR);
+ soa_name = name;
+ }
+ if (ns_name == NULL) {
+ negative_response = ISC_TRUE;
+ name->attributes |=
+ DNS_NAMEATTR_NCACHE;
+ rdataset->attributes |=
+ DNS_RDATASETATTR_NCACHE;
+ } else {
+ name->attributes |=
+ DNS_NAMEATTR_CACHE;
+ rdataset->attributes |=
+ DNS_RDATASETATTR_CACHE;
+ }
+ if (aa)
+ rdataset->trust =
+ dns_trust_authauthority;
+ else
+ rdataset->trust =
+ dns_trust_additional;
+ /*
+ * No additional data needs to be
+ * marked.
+ */
+ } else if (type == dns_rdatatype_ds) {
+ /*
+ * DS or SIG DS.
+ *
+ * These should only be here if
+ * this is a referral, and there
+ * should only be one DS.
+ */
+ if (negative_response)
+ return (DNS_R_FORMERR);
+ if (rdataset->type ==
+ dns_rdatatype_ds) {
+ if (ds_name != NULL &&
+ name != ds_name)
+ return (DNS_R_FORMERR);
+ ds_name = name;
+ }
+ name->attributes |=
+ DNS_NAMEATTR_CACHE;
+ rdataset->attributes |=
+ DNS_RDATASETATTR_CACHE;
+ if (aa)
+ rdataset->trust =
+ dns_trust_authauthority;
+ else
+ rdataset->trust =
+ dns_trust_additional;
+ }
+ }
+ }
+ result = dns_message_nextname(message, section);
+ if (result == ISC_R_NOMORE)
+ break;
+ else if (result != ISC_R_SUCCESS)
+ return (result);
+ }
+
+ /*
+ * Trigger lookups for DNS nameservers.
+ */
+ if (negative_response && message->rcode == dns_rcode_noerror &&
+ fctx->type == dns_rdatatype_ds && soa_name != NULL &&
+ dns_name_equal(soa_name, qname) &&
+ !dns_name_equal(qname, dns_rootname))
+ return (DNS_R_CHASEDSSERVERS);
+
+ /*
+ * Did we find anything?
+ */
+ if (!negative_response && ns_name == NULL) {
+ /*
+ * Nope.
+ */
+ if (oqname != NULL) {
+ /*
+ * We've already got a partial CNAME/DNAME chain,
+ * and haven't found else anything useful here, but
+ * no error has occurred since we have an answer.
+ */
+ return (ISC_R_SUCCESS);
+ } else {
+ /*
+ * The responder is insane.
+ */
+ return (DNS_R_FORMERR);
+ }
+ }
+
+ /*
+ * If we found both NS and SOA, they should be the same name.
+ */
+ if (ns_name != NULL && soa_name != NULL && ns_name != soa_name)
+ return (DNS_R_FORMERR);
+
+ /*
+ * Do we have a referral? (We only want to follow a referral if
+ * we're not following a chain.)
+ */
+ if (!negative_response && ns_name != NULL && oqname == NULL) {
+ /*
+ * We already know ns_name is a subdomain of fctx->domain.
+ * If ns_name is equal to fctx->domain, we're not making
+ * progress. We return DNS_R_FORMERR so that we'll keep
+ * trying other servers.
+ */
+ if (dns_name_equal(ns_name, &fctx->domain))
+ return (DNS_R_FORMERR);
+
+ /*
+ * If the referral name is not a parent of the query
+ * name, consider the responder insane.
+ */
+ if (! dns_name_issubdomain(&fctx->name, ns_name)) {
+ FCTXTRACE("referral to non-parent");
+ return (DNS_R_FORMERR);
+ }
+
+ /*
+ * Mark any additional data related to this rdataset.
+ * It's important that we do this before we change the
+ * query domain.
+ */
+ INSIST(ns_rdataset != NULL);
+ fctx->attributes |= FCTX_ATTR_GLUING;
+ (void)dns_rdataset_additionaldata(ns_rdataset, check_related,
+ fctx);
+ fctx->attributes &= ~FCTX_ATTR_GLUING;
+ /*
+ * NS rdatasets with 0 TTL cause problems.
+ * dns_view_findzonecut() will not find them when we
+ * try to follow the referral, and we'll SERVFAIL
+ * because the best nameservers are now above QDOMAIN.
+ * We force the TTL to 1 second to prevent this.
+ */
+ if (ns_rdataset->ttl == 0)
+ ns_rdataset->ttl = 1;
+ /*
+ * Set the current query domain to the referral name.
+ *
+ * XXXRTH We should check if we're in forward-only mode, and
+ * if so we should bail out.
+ */
+ INSIST(dns_name_countlabels(&fctx->domain) > 0);
+ dns_name_free(&fctx->domain, fctx->res->mctx);
+ if (dns_rdataset_isassociated(&fctx->nameservers))
+ dns_rdataset_disassociate(&fctx->nameservers);
+ dns_name_init(&fctx->domain, NULL);
+ result = dns_name_dup(ns_name, fctx->res->mctx, &fctx->domain);
+ if (result != ISC_R_SUCCESS)
+ return (result);
+ fctx->attributes |= FCTX_ATTR_WANTCACHE;
+ return (DNS_R_DELEGATION);
+ }
+
+ /*
+ * Since we're not doing a referral, we don't want to cache any
+ * NS RRs we may have found.
+ */
+ if (ns_name != NULL)
+ ns_name->attributes &= ~DNS_NAMEATTR_CACHE;
+
+ if (negative_response && oqname == NULL)
+ fctx->attributes |= FCTX_ATTR_WANTNCACHE;
+
+ return (ISC_R_SUCCESS);
+}
+
+static isc_result_t
+answer_response(fetchctx_t *fctx) {
+ isc_result_t result;
+ dns_message_t *message;
+ dns_name_t *name, *qname, tname;
+ dns_rdataset_t *rdataset;
+ isc_boolean_t done, external, chaining, aa, found, want_chaining;
+ isc_boolean_t have_answer, found_cname, found_type, wanted_chaining;
+ unsigned int aflag;
+ dns_rdatatype_t type;
+ dns_fixedname_t dname, fqname;
+
+ FCTXTRACE("answer_response");
+
+ message = fctx->rmessage;
+
+ /*
+ * Examine the answer section, marking those rdatasets which are
+ * part of the answer and should be cached.
+ */
+
+ done = ISC_FALSE;
+ found_cname = ISC_FALSE;
+ found_type = ISC_FALSE;
+ chaining = ISC_FALSE;
+ have_answer = ISC_FALSE;
+ want_chaining = ISC_FALSE;
+ if ((message->flags & DNS_MESSAGEFLAG_AA) != 0)
+ aa = ISC_TRUE;
+ else
+ aa = ISC_FALSE;
+ qname = &fctx->name;
+ type = fctx->type;
+ result = dns_message_firstname(message, DNS_SECTION_ANSWER);
+ while (!done && result == ISC_R_SUCCESS) {
+ name = NULL;
+ dns_message_currentname(message, DNS_SECTION_ANSWER, &name);
+ external = ISC_TF(!dns_name_issubdomain(name, &fctx->domain));
+ if (dns_name_equal(name, qname)) {
+ wanted_chaining = ISC_FALSE;
+ for (rdataset = ISC_LIST_HEAD(name->list);
+ rdataset != NULL;
+ rdataset = ISC_LIST_NEXT(rdataset, link)) {
+ found = ISC_FALSE;
+ want_chaining = ISC_FALSE;
+ aflag = 0;
+ if (rdataset->type == type && !found_cname) {
+ /*
+ * We've found an ordinary answer.
+ */
+ found = ISC_TRUE;
+ found_type = ISC_TRUE;
+ done = ISC_TRUE;
+ aflag = DNS_RDATASETATTR_ANSWER;
+ } else if (type == dns_rdatatype_any) {
+ /*
+ * We've found an answer matching
+ * an ANY query. There may be
+ * more.
+ */
+ found = ISC_TRUE;
+ aflag = DNS_RDATASETATTR_ANSWER;
+ } else if (rdataset->type == dns_rdatatype_rrsig
+ && rdataset->covers == type
+ && !found_cname) {
+ /*
+ * We've found a signature that
+ * covers the type we're looking for.
+ */
+ found = ISC_TRUE;
+ found_type = ISC_TRUE;
+ aflag = DNS_RDATASETATTR_ANSWERSIG;
+ } else if (rdataset->type ==
+ dns_rdatatype_cname
+ && !found_type) {
+ /*
+ * We're looking for something else,
+ * but we found a CNAME.
+ *
+ * Getting a CNAME response for some
+ * query types is an error.
+ */
+ if (type == dns_rdatatype_rrsig ||
+ type == dns_rdatatype_dnskey ||
+ type == dns_rdatatype_nsec)
+ return (DNS_R_FORMERR);
+ found = ISC_TRUE;
+ found_cname = ISC_TRUE;
+ want_chaining = ISC_TRUE;
+ aflag = DNS_RDATASETATTR_ANSWER;
+ result = cname_target(rdataset,
+ &tname);
+ if (result != ISC_R_SUCCESS)
+ return (result);
+ } else if (rdataset->type == dns_rdatatype_rrsig
+ && rdataset->covers ==
+ dns_rdatatype_cname
+ && !found_type) {
+ /*
+ * We're looking for something else,
+ * but we found a SIG CNAME.
+ */
+ found = ISC_TRUE;
+ found_cname = ISC_TRUE;
+ aflag = DNS_RDATASETATTR_ANSWERSIG;
+ }
+
+ if (found) {
+ /*
+ * We've found an answer to our
+ * question.
+ */
+ name->attributes |=
+ DNS_NAMEATTR_CACHE;
+ rdataset->attributes |=
+ DNS_RDATASETATTR_CACHE;
+ rdataset->trust = dns_trust_answer;
+ if (!chaining) {
+ /*
+ * This data is "the" answer
+ * to our question only if
+ * we're not chaining (i.e.
+ * if we haven't followed
+ * a CNAME or DNAME).
+ */
+ INSIST(!external);
+ if (aflag ==
+ DNS_RDATASETATTR_ANSWER)
+ have_answer = ISC_TRUE;
+ name->attributes |=
+ DNS_NAMEATTR_ANSWER;
+ rdataset->attributes |= aflag;
+ if (aa)
+ rdataset->trust =
+ dns_trust_authanswer;
+ } else if (external) {
+ /*
+ * This data is outside of
+ * our query domain, and
+ * may only be cached if it
+ * comes from a secure zone
+ * and validates.
+ */
+ rdataset->attributes |=
+ DNS_RDATASETATTR_EXTERNAL;
+ }
+
+ /*
+ * Mark any additional data related
+ * to this rdataset.
+ */
+ (void)dns_rdataset_additionaldata(
+ rdataset,
+ check_related,
+ fctx);
+
+ /*
+ * CNAME chaining.
+ */
+ if (want_chaining) {
+ wanted_chaining = ISC_TRUE;
+ name->attributes |=
+ DNS_NAMEATTR_CHAINING;
+ rdataset->attributes |=
+ DNS_RDATASETATTR_CHAINING;
+ qname = &tname;
+ }
+ }
+ /*
+ * We could add an "else" clause here and
+ * log that we're ignoring this rdataset.
+ */
+ }
+ /*
+ * If wanted_chaining is true, we've done
+ * some chaining as the result of processing
+ * this node, and thus we need to set
+ * chaining to true.
+ *
+ * We don't set chaining inside of the
+ * rdataset loop because doing that would
+ * cause us to ignore the signatures of
+ * CNAMEs.
+ */
+ if (wanted_chaining)
+ chaining = ISC_TRUE;
+ } else {
+ /*
+ * Look for a DNAME (or its SIG). Anything else is
+ * ignored.
+ */
+ wanted_chaining = ISC_FALSE;
+ for (rdataset = ISC_LIST_HEAD(name->list);
+ rdataset != NULL;
+ rdataset = ISC_LIST_NEXT(rdataset, link)) {
+ isc_boolean_t found_dname = ISC_FALSE;
+ found = ISC_FALSE;
+ aflag = 0;
+ if (rdataset->type == dns_rdatatype_dname) {
+ /*
+ * We're looking for something else,
+ * but we found a DNAME.
+ *
+ * If we're not chaining, then the
+ * DNAME should not be external.
+ */
+ if (!chaining && external)
+ return (DNS_R_FORMERR);
+ found = ISC_TRUE;
+ want_chaining = ISC_TRUE;
+ aflag = DNS_RDATASETATTR_ANSWER;
+ result = dname_target(rdataset,
+ qname, name,
+ &dname);
+ if (result == ISC_R_NOSPACE) {
+ /*
+ * We can't construct the
+ * DNAME target. Do not
+ * try to continue.
+ */
+ want_chaining = ISC_FALSE;
+ } else if (result != ISC_R_SUCCESS)
+ return (result);
+ else
+ found_dname = ISC_TRUE;
+ } else if (rdataset->type == dns_rdatatype_rrsig
+ && rdataset->covers ==
+ dns_rdatatype_dname) {
+ /*
+ * We've found a signature that
+ * covers the DNAME.
+ */
+ found = ISC_TRUE;
+ aflag = DNS_RDATASETATTR_ANSWERSIG;
+ }
+
+ if (found) {
+ /*
+ * We've found an answer to our
+ * question.
+ */
+ name->attributes |=
+ DNS_NAMEATTR_CACHE;
+ rdataset->attributes |=
+ DNS_RDATASETATTR_CACHE;
+ rdataset->trust = dns_trust_answer;
+ if (!chaining) {
+ /*
+ * This data is "the" answer
+ * to our question only if
+ * we're not chaining.
+ */
+ INSIST(!external);
+ if (aflag ==
+ DNS_RDATASETATTR_ANSWER)
+ have_answer = ISC_TRUE;
+ name->attributes |=
+ DNS_NAMEATTR_ANSWER;
+ rdataset->attributes |= aflag;
+ if (aa)
+ rdataset->trust =
+ dns_trust_authanswer;
+ } else if (external) {
+ rdataset->attributes |=
+ DNS_RDATASETATTR_EXTERNAL;
+ }
+
+ /*
+ * DNAME chaining.
+ */
+ if (found_dname) {
+ /*
+ * Copy the the dname into the
+ * qname fixed name.
+ *
+ * Although we check for
+ * failure of the copy
+ * operation, in practice it
+ * should never fail since
+ * we already know that the
+ * result fits in a fixedname.
+ */
+ dns_fixedname_init(&fqname);
+ result = dns_name_copy(
+ dns_fixedname_name(&dname),
+ dns_fixedname_name(&fqname),
+ NULL);
+ if (result != ISC_R_SUCCESS)
+ return (result);
+ wanted_chaining = ISC_TRUE;
+ name->attributes |=
+ DNS_NAMEATTR_CHAINING;
+ rdataset->attributes |=
+ DNS_RDATASETATTR_CHAINING;
+ qname = dns_fixedname_name(
+ &fqname);
+ }
+ }
+ }
+ if (wanted_chaining)
+ chaining = ISC_TRUE;
+ }
+ result = dns_message_nextname(message, DNS_SECTION_ANSWER);
+ }
+ if (result == ISC_R_NOMORE)
+ result = ISC_R_SUCCESS;
+ if (result != ISC_R_SUCCESS)
+ return (result);
+
+ /*
+ * We should have found an answer.
+ */
+ if (!have_answer)
+ return (DNS_R_FORMERR);
+
+ /*
+ * This response is now potentially cacheable.
+ */
+ fctx->attributes |= FCTX_ATTR_WANTCACHE;
+
+ /*
+ * Did chaining end before we got the final answer?
+ */
+ if (chaining) {
+ /*
+ * Yes. This may be a negative reply, so hand off
+ * authority section processing to the noanswer code.
+ * If it isn't a noanswer response, no harm will be
+ * done.
+ */
+ return (noanswer_response(fctx, qname, ISC_FALSE));
+ }
+
+ /*
+ * We didn't end with an incomplete chain, so the rcode should be
+ * "no error".
+ */
+ if (message->rcode != dns_rcode_noerror)
+ return (DNS_R_FORMERR);
+
+ /*
+ * Examine the authority section (if there is one).
+ *
+ * We expect there to be only one owner name for all the rdatasets
+ * in this section, and we expect that it is not external.
+ */
+ done = ISC_FALSE;
+ result = dns_message_firstname(message, DNS_SECTION_AUTHORITY);
+ while (!done && result == ISC_R_SUCCESS) {
+ name = NULL;
+ dns_message_currentname(message, DNS_SECTION_AUTHORITY, &name);
+ external = ISC_TF(!dns_name_issubdomain(name, &fctx->domain));
+ if (!external) {
+ /*
+ * We expect to find NS or SIG NS rdatasets, and
+ * nothing else.
+ */
+ for (rdataset = ISC_LIST_HEAD(name->list);
+ rdataset != NULL;
+ rdataset = ISC_LIST_NEXT(rdataset, link)) {
+ if (rdataset->type == dns_rdatatype_ns ||
+ (rdataset->type == dns_rdatatype_rrsig &&
+ rdataset->covers == dns_rdatatype_ns)) {
+ name->attributes |=
+ DNS_NAMEATTR_CACHE;
+ rdataset->attributes |=
+ DNS_RDATASETATTR_CACHE;
+ if (aa && !chaining)
+ rdataset->trust =
+ dns_trust_authauthority;
+ else
+ rdataset->trust =
+ dns_trust_additional;
+
+ /*
+ * Mark any additional data related
+ * to this rdataset.
+ */
+ (void)dns_rdataset_additionaldata(
+ rdataset,
+ check_related,
+ fctx);
+ done = ISC_TRUE;
+ }
+ }
+ }
+ result = dns_message_nextname(message, DNS_SECTION_AUTHORITY);
+ }
+ if (result == ISC_R_NOMORE)
+ result = ISC_R_SUCCESS;
+
+ return (result);
+}
+
+static void
+resume_dslookup(isc_task_t *task, isc_event_t *event) {
+ dns_fetchevent_t *fevent;
+ dns_resolver_t *res;
+ fetchctx_t *fctx;
+ isc_result_t result;
+ isc_boolean_t bucket_empty = ISC_FALSE;
+ isc_boolean_t locked = ISC_FALSE;
+ unsigned int bucketnum;
+ dns_rdataset_t nameservers;
+ dns_fixedname_t fixed;
+ dns_name_t *domain;
+
+ REQUIRE(event->ev_type == DNS_EVENT_FETCHDONE);
+ fevent = (dns_fetchevent_t *)event;
+ fctx = event->ev_arg;
+ REQUIRE(VALID_FCTX(fctx));
+ res = fctx->res;
+
+ UNUSED(task);
+ FCTXTRACE("resume_dslookup");
+
+ if (fevent->node != NULL)
+ dns_db_detachnode(fevent->db, &fevent->node);
+ if (fevent->db != NULL)
+ dns_db_detach(&fevent->db);
+
+ dns_rdataset_init(&nameservers);
+
+ bucketnum = fctx->bucketnum;
+ if (fevent->result == ISC_R_CANCELED) {
+ dns_resolver_destroyfetch(&fctx->nsfetch);
+ fctx_done(fctx, ISC_R_CANCELED);
+ } else if (fevent->result == ISC_R_SUCCESS) {
+
+ FCTXTRACE("resuming DS lookup");
+
+ dns_resolver_destroyfetch(&fctx->nsfetch);
+ if (dns_rdataset_isassociated(&fctx->nameservers))
+ dns_rdataset_disassociate(&fctx->nameservers);
+ dns_rdataset_clone(fevent->rdataset, &fctx->nameservers);
+ dns_name_free(&fctx->domain, fctx->res->mctx);
+ dns_name_init(&fctx->domain, NULL);
+ result = dns_name_dup(&fctx->nsname, fctx->res->mctx,
+ &fctx->domain);
+ if (result != ISC_R_SUCCESS) {
+ fctx_done(fctx, DNS_R_SERVFAIL);
+ goto cleanup;
+ }
+ /*
+ * Try again.
+ */
+ fctx_try(fctx);
+ } else {
+ unsigned int n;
+
+ /*
+ * Retrieve state from fctx->nsfetch before we destroy it.
+ */
+ dns_fixedname_init(&fixed);
+ domain = dns_fixedname_name(&fixed);
+ dns_name_copy(&fctx->nsfetch->private->domain, domain, NULL);
+ dns_rdataset_clone(&fctx->nsfetch->private->nameservers,
+ &nameservers);
+ dns_resolver_destroyfetch(&fctx->nsfetch);
+ if (dns_name_equal(&fctx->nsname, domain)) {
+ fctx_done(fctx, DNS_R_SERVFAIL);
+ goto cleanup;
+ }
+ n = dns_name_countlabels(&fctx->nsname);
+ dns_name_getlabelsequence(&fctx->nsname, 1, n - 1,
+ &fctx->nsname);
+
+ if (dns_rdataset_isassociated(fevent->rdataset))
+ dns_rdataset_disassociate(fevent->rdataset);
+ FCTXTRACE("continuing to look for parent's NS records");
+ result = dns_resolver_createfetch(fctx->res, &fctx->nsname,
+ dns_rdatatype_ns, domain,
+ &nameservers, NULL, 0, task,
+ resume_dslookup, fctx,
+ &fctx->nsrrset, NULL,
+ &fctx->nsfetch);
+ if (result != ISC_R_SUCCESS)
+ fctx_done(fctx, result);
+ else {
+ LOCK(&res->buckets[bucketnum].lock);
+ locked = ISC_TRUE;
+ fctx->references++;
+ }
+ }
+
+ cleanup:
+ if (dns_rdataset_isassociated(&nameservers))
+ dns_rdataset_disassociate(&nameservers);
+ if (dns_rdataset_isassociated(fevent->rdataset))
+ dns_rdataset_disassociate(fevent->rdataset);
+ INSIST(fevent->sigrdataset == NULL);
+ isc_event_free(&event);
+ if (!locked)
+ LOCK(&res->buckets[bucketnum].lock);
+ fctx->references--;
+ if (fctx->references == 0)
+ bucket_empty = fctx_destroy(fctx);
+ UNLOCK(&res->buckets[bucketnum].lock);
+ if (bucket_empty)
+ empty_bucket(res);
+}
+
+static inline void
+checknamessection(dns_message_t *message, dns_section_t section) {
+ isc_result_t result;
+ dns_name_t *name;
+ dns_rdata_t rdata = DNS_RDATA_INIT;
+ dns_rdataset_t *rdataset;
+
+ for (result = dns_message_firstname(message, section);
+ result == ISC_R_SUCCESS;
+ result = dns_message_nextname(message, section))
+ {
+ name = NULL;
+ dns_message_currentname(message, section, &name);
+ for (rdataset = ISC_LIST_HEAD(name->list);
+ rdataset != NULL;
+ rdataset = ISC_LIST_NEXT(rdataset, link)) {
+ for (result = dns_rdataset_first(rdataset);
+ result == ISC_R_SUCCESS;
+ result = dns_rdataset_next(rdataset)) {
+ dns_rdataset_current(rdataset, &rdata);
+ if (!dns_rdata_checkowner(name, rdata.rdclass,
+ rdata.type,
+ ISC_FALSE) ||
+ !dns_rdata_checknames(&rdata, name, NULL))
+ {
+ rdataset->attributes |=
+ DNS_RDATASETATTR_CHECKNAMES;
+ }
+ dns_rdata_reset(&rdata);
+ }
+ }
+ }
+}
+
+static void
+checknames(dns_message_t *message) {
+
+ checknamessection(message, DNS_SECTION_ANSWER);
+ checknamessection(message, DNS_SECTION_AUTHORITY);
+ checknamessection(message, DNS_SECTION_ADDITIONAL);
+}
+
+static void
+resquery_response(isc_task_t *task, isc_event_t *event) {
+ isc_result_t result = ISC_R_SUCCESS;
+ resquery_t *query = event->ev_arg;
+ dns_dispatchevent_t *devent = (dns_dispatchevent_t *)event;
+ isc_boolean_t keep_trying, get_nameservers, resend;
+ isc_boolean_t truncated;
+ dns_message_t *message;
+ fetchctx_t *fctx;
+ dns_name_t *fname;
+ dns_fixedname_t foundname;
+ isc_stdtime_t now;
+ isc_time_t tnow, *finish;
+ dns_adbaddrinfo_t *addrinfo;
+ unsigned int options;
+ unsigned int findoptions;
+ isc_result_t broken_server;
+
+ REQUIRE(VALID_QUERY(query));
+ fctx = query->fctx;
+ options = query->options;
+ REQUIRE(VALID_FCTX(fctx));
+ REQUIRE(event->ev_type == DNS_EVENT_DISPATCH);
+
+ QTRACE("response");
+
+ (void)isc_timer_touch(fctx->timer);
+
+ keep_trying = ISC_FALSE;
+ broken_server = ISC_R_SUCCESS;
+ get_nameservers = ISC_FALSE;
+ resend = ISC_FALSE;
+ truncated = ISC_FALSE;
+ finish = NULL;
+
+ if (fctx->res->exiting) {
+ result = ISC_R_SHUTTINGDOWN;
+ goto done;
+ }
+
+ fctx->timeouts = 0;
+
+ /*
+ * XXXRTH We should really get the current time just once. We
+ * need a routine to convert from an isc_time_t to an
+ * isc_stdtime_t.
+ */
+ TIME_NOW(&tnow);
+ finish = &tnow;
+ isc_stdtime_get(&now);
+
+ /*
+ * Did the dispatcher have a problem?
+ */
+ if (devent->result != ISC_R_SUCCESS) {
+ if (devent->result == ISC_R_EOF &&
+ (query->options & DNS_FETCHOPT_NOEDNS0) == 0) {
+ /*
+ * The problem might be that they
+ * don't understand EDNS0. Turn it
+ * off and try again.
+ */
+ options |= DNS_FETCHOPT_NOEDNS0;
+ resend = ISC_TRUE;
+ /*
+ * Remember that they don't like EDNS0.
+ */
+ dns_adb_changeflags(fctx->adb,
+ query->addrinfo,
+ DNS_FETCHOPT_NOEDNS0,
+ DNS_FETCHOPT_NOEDNS0);
+ } else {
+ /*
+ * There's no hope for this query.
+ */
+ keep_trying = ISC_TRUE;
+ }
+ goto done;
+ }
+
+ message = fctx->rmessage;
+
+ if (query->tsig != NULL) {
+ result = dns_message_setquerytsig(message, query->tsig);
+ if (result != ISC_R_SUCCESS)
+ goto done;
+ }
+
+ if (query->tsigkey) {
+ result = dns_message_settsigkey(message, query->tsigkey);
+ if (result != ISC_R_SUCCESS)
+ goto done;
+ }
+
+ result = dns_message_parse(message, &devent->buffer, 0);
+ if (result != ISC_R_SUCCESS) {
+ switch (result) {
+ case ISC_R_UNEXPECTEDEND:
+ if (!message->question_ok ||
+ (message->flags & DNS_MESSAGEFLAG_TC) == 0 ||
+ (options & DNS_FETCHOPT_TCP) != 0) {
+ /*
+ * Either the message ended prematurely,
+ * and/or wasn't marked as being truncated,
+ * and/or this is a response to a query we
+ * sent over TCP. In all of these cases,
+ * something is wrong with the remote
+ * server and we don't want to retry using
+ * TCP.
+ */
+ if ((query->options & DNS_FETCHOPT_NOEDNS0)
+ == 0) {
+ /*
+ * The problem might be that they
+ * don't understand EDNS0. Turn it
+ * off and try again.
+ */
+ options |= DNS_FETCHOPT_NOEDNS0;
+ resend = ISC_TRUE;
+ /*
+ * Remember that they don't like EDNS0.
+ */
+ dns_adb_changeflags(
+ fctx->adb,
+ query->addrinfo,
+ DNS_FETCHOPT_NOEDNS0,
+ DNS_FETCHOPT_NOEDNS0);
+ } else {
+ broken_server = result;
+ keep_trying = ISC_TRUE;
+ }
+ goto done;
+ }
+ /*
+ * We defer retrying via TCP for a bit so we can
+ * check out this message further.
+ */
+ truncated = ISC_TRUE;
+ break;
+ case DNS_R_FORMERR:
+ if ((query->options & DNS_FETCHOPT_NOEDNS0) == 0) {
+ /*
+ * The problem might be that they
+ * don't understand EDNS0. Turn it
+ * off and try again.
+ */
+ options |= DNS_FETCHOPT_NOEDNS0;
+ resend = ISC_TRUE;
+ /*
+ * Remember that they don't like EDNS0.
+ */
+ dns_adb_changeflags(fctx->adb,
+ query->addrinfo,
+ DNS_FETCHOPT_NOEDNS0,
+ DNS_FETCHOPT_NOEDNS0);
+ } else {
+ broken_server = DNS_R_UNEXPECTEDRCODE;
+ keep_trying = ISC_TRUE;
+ }
+ goto done;
+ default:
+ /*
+ * Something bad has happened.
+ */
+ goto done;
+ }
+ }
+
+ /*
+ * If the message is signed, check the signature. If not, this
+ * returns success anyway.
+ */
+ result = dns_message_checksig(message, fctx->res->view);
+ if (result != ISC_R_SUCCESS)
+ goto done;
+
+ /*
+ * The dispatcher should ensure we only get responses with QR set.
+ */
+ INSIST((message->flags & DNS_MESSAGEFLAG_QR) != 0);
+ /*
+ * INSIST() that the message comes from the place we sent it to,
+ * since the dispatch code should ensure this.
+ *
+ * INSIST() that the message id is correct (this should also be
+ * ensured by the dispatch code).
+ */
+
+
+ /*
+ * Deal with truncated responses by retrying using TCP.
+ */
+ if ((message->flags & DNS_MESSAGEFLAG_TC) != 0)
+ truncated = ISC_TRUE;
+
+ if (truncated) {
+ if ((options & DNS_FETCHOPT_TCP) != 0) {
+ broken_server = DNS_R_TRUNCATEDTCP;
+ keep_trying = ISC_TRUE;
+ } else {
+ options |= DNS_FETCHOPT_TCP;
+ resend = ISC_TRUE;
+ }
+ goto done;
+ }
+
+ /*
+ * Is it a query response?
+ */
+ if (message->opcode != dns_opcode_query) {
+ /* XXXRTH Log */
+ broken_server = DNS_R_UNEXPECTEDOPCODE;
+ keep_trying = ISC_TRUE;
+ goto done;
+ }
+
+ /*
+ * Is the remote server broken, or does it dislike us?
+ */
+ if (message->rcode != dns_rcode_noerror &&
+ message->rcode != dns_rcode_nxdomain) {
+ if ((message->rcode == dns_rcode_formerr ||
+ message->rcode == dns_rcode_notimp ||
+ message->rcode == dns_rcode_servfail) &&
+ (query->options & DNS_FETCHOPT_NOEDNS0) == 0) {
+ /*
+ * It's very likely they don't like EDNS0.
+ *
+ * XXXRTH We should check if the question
+ * we're asking requires EDNS0, and
+ * if so, we should bail out.
+ */
+ options |= DNS_FETCHOPT_NOEDNS0;
+ resend = ISC_TRUE;
+ /*
+ * Remember that they don't like EDNS0.
+ */
+ if (message->rcode != dns_rcode_servfail)
+ dns_adb_changeflags(fctx->adb, query->addrinfo,
+ DNS_FETCHOPT_NOEDNS0,
+ DNS_FETCHOPT_NOEDNS0);
+ } else if (message->rcode == dns_rcode_formerr) {
+ if (ISFORWARDER(query->addrinfo)) {
+ /*
+ * This forwarder doesn't understand us,
+ * but other forwarders might. Keep trying.
+ */
+ broken_server = DNS_R_REMOTEFORMERR;
+ keep_trying = ISC_TRUE;
+ } else {
+ /*
+ * The server doesn't understand us. Since
+ * all servers for a zone need similar
+ * capabilities, we assume that we will get
+ * FORMERR from all servers, and thus we
+ * cannot make any more progress with this
+ * fetch.
+ */
+ result = DNS_R_FORMERR;
+ }
+ } else if (message->rcode == dns_rcode_yxdomain) {
+ /*
+ * DNAME mapping failed because the new name
+ * was too long. There's no chance of success
+ * for this fetch.
+ */
+ result = DNS_R_YXDOMAIN;
+ } else {
+ /*
+ * XXXRTH log.
+ */
+ broken_server = DNS_R_UNEXPECTEDRCODE;
+ INSIST(broken_server != ISC_R_SUCCESS);
+ keep_trying = ISC_TRUE;
+ }
+ goto done;
+ }
+
+ /*
+ * Is the question the same as the one we asked?
+ */
+ result = same_question(fctx);
+ if (result != ISC_R_SUCCESS) {
+ /* XXXRTH Log */
+ if (result == DNS_R_FORMERR)
+ keep_trying = ISC_TRUE;
+ goto done;
+ }
+
+ /*
+ * Is the server lame?
+ */
+ if (fctx->res->lame_ttl != 0 && !ISFORWARDER(query->addrinfo) &&
+ is_lame(fctx)) {
+ log_lame(fctx, query->addrinfo);
+ result = dns_adb_marklame(fctx->adb, query->addrinfo,
+ &fctx->domain,
+ now + fctx->res->lame_ttl);
+ if (result != ISC_R_SUCCESS)
+ isc_log_write(dns_lctx, DNS_LOGCATEGORY_RESOLVER,
+ DNS_LOGMODULE_RESOLVER, ISC_LOG_ERROR,
+ "could not mark server as lame: %s",
+ isc_result_totext(result));
+ broken_server = DNS_R_LAME;
+ keep_trying = ISC_TRUE;
+ goto done;
+ }
+
+ /*
+ * Enforce delegations only zones like NET and COM.
+ */
+ if (!ISFORWARDER(query->addrinfo) &&
+ dns_view_isdelegationonly(fctx->res->view, &fctx->domain) &&
+ !dns_name_equal(&fctx->domain, &fctx->name) &&
+ fix_mustbedelegationornxdomain(message, fctx)) {
+ char namebuf[DNS_NAME_FORMATSIZE];
+ char domainbuf[DNS_NAME_FORMATSIZE];
+ char addrbuf[ISC_SOCKADDR_FORMATSIZE];
+ char classbuf[64];
+ char typebuf[64];
+
+ dns_name_format(&fctx->name, namebuf, sizeof(namebuf));
+ dns_name_format(&fctx->domain, domainbuf, sizeof(domainbuf));
+ dns_rdatatype_format(fctx->type, typebuf, sizeof(typebuf));
+ dns_rdataclass_format(fctx->res->rdclass, classbuf,
+ sizeof(classbuf));
+ isc_sockaddr_format(&query->addrinfo->sockaddr, addrbuf,
+ sizeof(addrbuf));
+
+ isc_log_write(dns_lctx, DNS_LOGCATEGORY_DELEGATION_ONLY,
+ DNS_LOGMODULE_RESOLVER, ISC_LOG_NOTICE,
+ "enforced delegation-only for '%s' (%s/%s/%s) "
+ "from %s",
+ domainbuf, namebuf, typebuf, classbuf, addrbuf);
+ }
+
+ if ((fctx->res->options | DNS_RESOLVER_CHECKNAMES) != 0)
+ checknames(message);
+
+ /*
+ * Did we get any answers?
+ */
+ if (message->counts[DNS_SECTION_ANSWER] > 0 &&
+ (message->rcode == dns_rcode_noerror ||
+ message->rcode == dns_rcode_nxdomain)) {
+ /*
+ * We've got answers. However, if we sent
+ * a BIND 8 server an NS query, it may have
+ * incorrectly responded with a non-authoritative
+ * answer instead of a referral. Since this
+ * answer lacks the SIGs necessary to do DNSSEC
+ * validation, we must invoke the following special
+ * kludge to treat it as a referral.
+ */
+ if (fctx->type == dns_rdatatype_ns &&
+ (message->flags & DNS_MESSAGEFLAG_AA) == 0 &&
+ !ISFORWARDER(query->addrinfo))
+ {
+ result = noanswer_response(fctx, NULL, ISC_TRUE);
+ if (result != DNS_R_DELEGATION) {
+ /*
+ * The answer section must have contained
+ * something other than the NS records
+ * we asked for. Since AA is not set
+ * and the server is not a forwarder,
+ * it is technically lame and it's easier
+ * to treat it as such than to figure out
+ * some more elaborate course of action.
+ */
+ broken_server = DNS_R_LAME;
+ keep_trying = ISC_TRUE;
+ goto done;
+ }
+ goto force_referral;
+ }
+ result = answer_response(fctx);
+ if (result != ISC_R_SUCCESS) {
+ if (result == DNS_R_FORMERR)
+ keep_trying = ISC_TRUE;
+ goto done;
+ }
+ } else if (message->counts[DNS_SECTION_AUTHORITY] > 0 ||
+ message->rcode == dns_rcode_noerror ||
+ message->rcode == dns_rcode_nxdomain) {
+ /*
+ * NXDOMAIN, NXRDATASET, or referral.
+ */
+ result = noanswer_response(fctx, NULL, ISC_FALSE);
+ if (result == DNS_R_CHASEDSSERVERS) {
+ } else if (result == DNS_R_DELEGATION) {
+ force_referral:
+ /*
+ * We don't have the answer, but we know a better
+ * place to look.
+ */
+ get_nameservers = ISC_TRUE;
+ keep_trying = ISC_TRUE;
+ /*
+ * We have a new set of name servers, and it
+ * has not experienced any restarts yet.
+ */
+ fctx->restarts = 0;
+ result = ISC_R_SUCCESS;
+ } else if (result != ISC_R_SUCCESS) {
+ /*
+ * Something has gone wrong.
+ */
+ if (result == DNS_R_FORMERR)
+ keep_trying = ISC_TRUE;
+ goto done;
+ }
+ } else {
+ /*
+ * The server is insane.
+ */
+ /* XXXRTH Log */
+ broken_server = DNS_R_UNEXPECTEDRCODE;
+ keep_trying = ISC_TRUE;
+ goto done;
+ }
+
+ /*
+ * Follow additional section data chains.
+ */
+ chase_additional(fctx);
+
+ /*
+ * Cache the cacheable parts of the message. This may also cause
+ * work to be queued to the DNSSEC validator.
+ */
+ if (WANTCACHE(fctx)) {
+ result = cache_message(fctx, now);
+ if (result != ISC_R_SUCCESS)
+ goto done;
+ }
+
+ /*
+ * Ncache the negatively cacheable parts of the message. This may
+ * also cause work to be queued to the DNSSEC validator.
+ */
+ if (WANTNCACHE(fctx)) {
+ dns_rdatatype_t covers;
+ if (message->rcode == dns_rcode_nxdomain)
+ covers = dns_rdatatype_any;
+ else
+ covers = fctx->type;
+
+ /*
+ * Cache any negative cache entries in the message.
+ */
+ result = ncache_message(fctx, covers, now);
+ }
+
+ done:
+ /*
+ * Remember the query's addrinfo, in case we need to mark the
+ * server as broken.
+ */
+ addrinfo = query->addrinfo;
+
+ /*
+ * Cancel the query.
+ *
+ * XXXRTH Don't cancel the query if waiting for validation?
+ */
+ fctx_cancelquery(&query, &devent, finish, ISC_FALSE);
+
+ if (keep_trying) {
+ if (result == DNS_R_FORMERR)
+ broken_server = DNS_R_FORMERR;
+ if (broken_server != ISC_R_SUCCESS) {
+ /*
+ * Add this server to the list of bad servers for
+ * this fctx.
+ */
+ add_bad(fctx, &addrinfo->sockaddr, broken_server);
+ }
+
+ if (get_nameservers) {
+ dns_name_t *name;
+ dns_fixedname_init(&foundname);
+ fname = dns_fixedname_name(&foundname);
+ if (result != ISC_R_SUCCESS) {
+ fctx_done(fctx, DNS_R_SERVFAIL);
+ return;
+ }
+ findoptions = 0;
+ if ((options & DNS_FETCHOPT_UNSHARED) == 0)
+ name = &fctx->name;
+ else
+ name = &fctx->domain;
+ result = dns_view_findzonecut(fctx->res->view,
+ name, fname,
+ now, 0, ISC_TRUE,
+ &fctx->nameservers,
+ NULL);
+ if (result != ISC_R_SUCCESS) {
+ FCTXTRACE("couldn't find a zonecut");
+ fctx_done(fctx, DNS_R_SERVFAIL);
+ return;
+ }
+ if (!dns_name_issubdomain(fname, &fctx->domain)) {
+ /*
+ * The best nameservers are now above our
+ * QDOMAIN.
+ */
+ FCTXTRACE("nameservers now above QDOMAIN");
+ fctx_done(fctx, DNS_R_SERVFAIL);
+ return;
+ }
+ dns_name_free(&fctx->domain, fctx->res->mctx);
+ dns_name_init(&fctx->domain, NULL);
+ result = dns_name_dup(fname, fctx->res->mctx,
+ &fctx->domain);
+ if (result != ISC_R_SUCCESS) {
+ fctx_done(fctx, DNS_R_SERVFAIL);
+ return;
+ }
+ fctx_cancelqueries(fctx, ISC_TRUE);
+ fctx_cleanupfinds(fctx);
+ fctx_cleanupaltfinds(fctx);
+ fctx_cleanupforwaddrs(fctx);
+ fctx_cleanupaltaddrs(fctx);
+ }
+ /*
+ * Try again.
+ */
+ fctx_try(fctx);
+ } else if (resend) {
+ /*
+ * Resend (probably with changed options).
+ */
+ FCTXTRACE("resend");
+ result = fctx_query(fctx, addrinfo, options);
+ if (result != ISC_R_SUCCESS)
+ fctx_done(fctx, result);
+ } else if (result == ISC_R_SUCCESS && !HAVE_ANSWER(fctx)) {
+ /*
+ * All has gone well so far, but we are waiting for the
+ * DNSSEC validator to validate the answer.
+ */
+ FCTXTRACE("wait for validator");
+ fctx_cancelqueries(fctx, ISC_TRUE);
+ /*
+ * We must not retransmit while the validator is working;
+ * it has references to the current rmessage.
+ */
+ result = fctx_stopidletimer(fctx);
+ if (result != ISC_R_SUCCESS)
+ fctx_done(fctx, result);
+ } else if (result == DNS_R_CHASEDSSERVERS) {
+ unsigned int n;
+ add_bad(fctx, &addrinfo->sockaddr, result);
+ fctx_cancelqueries(fctx, ISC_TRUE);
+ fctx_cleanupfinds(fctx);
+ fctx_cleanupforwaddrs(fctx);
+
+ n = dns_name_countlabels(&fctx->name);
+ dns_name_getlabelsequence(&fctx->name, 1, n - 1, &fctx->nsname);
+
+ FCTXTRACE("suspending DS lookup to find parent's NS records");
+
+ result = dns_resolver_createfetch(fctx->res, &fctx->nsname,
+ dns_rdatatype_ns,
+ NULL, NULL, NULL, 0, task,
+ resume_dslookup, fctx,
+ &fctx->nsrrset, NULL,
+ &fctx->nsfetch);
+ if (result != ISC_R_SUCCESS)
+ fctx_done(fctx, result);
+ LOCK(&fctx->res->buckets[fctx->bucketnum].lock);
+ fctx->references++;
+ UNLOCK(&fctx->res->buckets[fctx->bucketnum].lock);
+ result = fctx_stopidletimer(fctx);
+ if (result != ISC_R_SUCCESS)
+ fctx_done(fctx, result);
+ } else {
+ /*
+ * We're done.
+ */
+ fctx_done(fctx, result);
+ }
+}
+
+
+/***
+ *** Resolver Methods
+ ***/
+
+static void
+destroy(dns_resolver_t *res) {
+ unsigned int i;
+ alternate_t *a;
+
+ REQUIRE(res->references == 0);
+ REQUIRE(!res->priming);
+ REQUIRE(res->primefetch == NULL);
+
+ RTRACE("destroy");
+
+ INSIST(res->nfctx == 0);
+
+ DESTROYLOCK(&res->primelock);
+ DESTROYLOCK(&res->nlock);
+ DESTROYLOCK(&res->lock);
+ for (i = 0; i < res->nbuckets; i++) {
+ INSIST(ISC_LIST_EMPTY(res->buckets[i].fctxs));
+ isc_task_shutdown(res->buckets[i].task);
+ isc_task_detach(&res->buckets[i].task);
+ DESTROYLOCK(&res->buckets[i].lock);
+ }
+ isc_mem_put(res->mctx, res->buckets,
+ res->nbuckets * sizeof(fctxbucket_t));
+ if (res->dispatchv4 != NULL)
+ dns_dispatch_detach(&res->dispatchv4);
+ if (res->dispatchv6 != NULL)
+ dns_dispatch_detach(&res->dispatchv6);
+ while ((a = ISC_LIST_HEAD(res->alternates)) != NULL) {
+ ISC_LIST_UNLINK(res->alternates, a, link);
+ if (!a->isaddress)
+ dns_name_free(&a->_u._n.name, res->mctx);
+ isc_mem_put(res->mctx, a, sizeof(*a));
+ }
+ dns_resolver_reset_algorithms(res);
+ dns_resolver_resetmustbesecure(res);
+#if USE_ALGLOCK
+ isc_rwlock_destroy(&res->alglock);
+#endif
+#if USE_MBSLOCK
+ isc_rwlock_destroy(&res->mbslock);
+#endif
+ res->magic = 0;
+ isc_mem_put(res->mctx, res, sizeof(*res));
+}
+
+static void
+send_shutdown_events(dns_resolver_t *res) {
+ isc_event_t *event, *next_event;
+ isc_task_t *etask;
+
+ /*
+ * Caller must be holding the resolver lock.
+ */
+
+ for (event = ISC_LIST_HEAD(res->whenshutdown);
+ event != NULL;
+ event = next_event) {
+ next_event = ISC_LIST_NEXT(event, ev_link);
+ ISC_LIST_UNLINK(res->whenshutdown, event, ev_link);
+ etask = event->ev_sender;
+ event->ev_sender = res;
+ isc_task_sendanddetach(&etask, &event);
+ }
+}
+
+static void
+empty_bucket(dns_resolver_t *res) {
+ RTRACE("empty_bucket");
+
+ LOCK(&res->lock);
+
+ INSIST(res->activebuckets > 0);
+ res->activebuckets--;
+ if (res->activebuckets == 0)
+ send_shutdown_events(res);
+
+ UNLOCK(&res->lock);
+}
+
+isc_result_t
+dns_resolver_create(dns_view_t *view,
+ isc_taskmgr_t *taskmgr, unsigned int ntasks,
+ isc_socketmgr_t *socketmgr,
+ isc_timermgr_t *timermgr,
+ unsigned int options,
+ dns_dispatchmgr_t *dispatchmgr,
+ dns_dispatch_t *dispatchv4,
+ dns_dispatch_t *dispatchv6,
+ dns_resolver_t **resp)
+{
+ dns_resolver_t *res;
+ isc_result_t result = ISC_R_SUCCESS;
+ unsigned int i, buckets_created = 0;
+ char name[16];
+
+ /*
+ * Create a resolver.
+ */
+
+ REQUIRE(DNS_VIEW_VALID(view));
+ REQUIRE(ntasks > 0);
+ REQUIRE(resp != NULL && *resp == NULL);
+ REQUIRE(dispatchmgr != NULL);
+ REQUIRE(dispatchv4 != NULL || dispatchv6 != NULL);
+
+ res = isc_mem_get(view->mctx, sizeof(*res));
+ if (res == NULL)
+ return (ISC_R_NOMEMORY);
+ RTRACE("create");
+ res->mctx = view->mctx;
+ res->rdclass = view->rdclass;
+ res->socketmgr = socketmgr;
+ res->timermgr = timermgr;
+ res->taskmgr = taskmgr;
+ res->dispatchmgr = dispatchmgr;
+ res->view = view;
+ res->options = options;
+ res->lame_ttl = 0;
+ ISC_LIST_INIT(res->alternates);
+ res->udpsize = RECV_BUFFER_SIZE;
+ res->algorithms = NULL;
+ res->mustbesecure = NULL;
+
+ res->nbuckets = ntasks;
+ res->activebuckets = ntasks;
+ res->buckets = isc_mem_get(view->mctx,
+ ntasks * sizeof(fctxbucket_t));
+ if (res->buckets == NULL) {
+ result = ISC_R_NOMEMORY;
+ goto cleanup_res;
+ }
+ for (i = 0; i < ntasks; i++) {
+ result = isc_mutex_init(&res->buckets[i].lock);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_buckets;
+ res->buckets[i].task = NULL;
+ result = isc_task_create(taskmgr, 0, &res->buckets[i].task);
+ if (result != ISC_R_SUCCESS) {
+ DESTROYLOCK(&res->buckets[i].lock);
+ goto cleanup_buckets;
+ }
+ snprintf(name, sizeof(name), "res%u", i);
+ isc_task_setname(res->buckets[i].task, name, res);
+ ISC_LIST_INIT(res->buckets[i].fctxs);
+ res->buckets[i].exiting = ISC_FALSE;
+ buckets_created++;
+ }
+
+ res->dispatchv4 = NULL;
+ if (dispatchv4 != NULL)
+ dns_dispatch_attach(dispatchv4, &res->dispatchv4);
+ res->dispatchv6 = NULL;
+ if (dispatchv6 != NULL)
+ dns_dispatch_attach(dispatchv6, &res->dispatchv6);
+
+ res->references = 1;
+ res->exiting = ISC_FALSE;
+ res->frozen = ISC_FALSE;
+ ISC_LIST_INIT(res->whenshutdown);
+ res->priming = ISC_FALSE;
+ res->primefetch = NULL;
+ res->nfctx = 0;
+
+ result = isc_mutex_init(&res->lock);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_dispatches;
+
+ result = isc_mutex_init(&res->nlock);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_lock;
+
+ result = isc_mutex_init(&res->primelock);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_nlock;
+
+#if USE_ALGLOCK
+ result = isc_rwlock_init(&res->alglock, 0, 0);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_primelock;
+#endif
+#if USE_MBSLOCK
+ result = isc_rwlock_init(&res->mbslock, 0, 0);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_alglock;
+#endif
+
+ res->magic = RES_MAGIC;
+
+ *resp = res;
+
+ return (ISC_R_SUCCESS);
+
+#if USE_MBSLOCK
+ cleanup_alglock:
+#if USE_ALGLOCK
+ isc_rwlock_destroy(&res->alglock);
+#endif
+#endif
+#if USE_ALGLOCK || USE_MBSLOCK
+ cleanup_primelock:
+ DESTROYLOCK(&res->primelock);
+#endif
+
+ cleanup_nlock:
+ DESTROYLOCK(&res->nlock);
+
+ cleanup_lock:
+ DESTROYLOCK(&res->lock);
+
+ cleanup_dispatches:
+ if (res->dispatchv6 != NULL)
+ dns_dispatch_detach(&res->dispatchv6);
+ if (res->dispatchv4 != NULL)
+ dns_dispatch_detach(&res->dispatchv4);
+
+ cleanup_buckets:
+ for (i = 0; i < buckets_created; i++) {
+ DESTROYLOCK(&res->buckets[i].lock);
+ isc_task_shutdown(res->buckets[i].task);
+ isc_task_detach(&res->buckets[i].task);
+ }
+ isc_mem_put(view->mctx, res->buckets,
+ res->nbuckets * sizeof(fctxbucket_t));
+
+ cleanup_res:
+ isc_mem_put(view->mctx, res, sizeof(*res));
+
+ return (result);
+}
+
+static void
+prime_done(isc_task_t *task, isc_event_t *event) {
+ dns_resolver_t *res;
+ dns_fetchevent_t *fevent;
+ dns_fetch_t *fetch;
+
+ REQUIRE(event->ev_type == DNS_EVENT_FETCHDONE);
+ fevent = (dns_fetchevent_t *)event;
+ res = event->ev_arg;
+ REQUIRE(VALID_RESOLVER(res));
+
+ UNUSED(task);
+
+ LOCK(&res->lock);
+
+ INSIST(res->priming);
+ res->priming = ISC_FALSE;
+ LOCK(&res->primelock);
+ fetch = res->primefetch;
+ res->primefetch = NULL;
+ UNLOCK(&res->primelock);
+
+ UNLOCK(&res->lock);
+
+ if (fevent->node != NULL)
+ dns_db_detachnode(fevent->db, &fevent->node);
+ if (fevent->db != NULL)
+ dns_db_detach(&fevent->db);
+ if (dns_rdataset_isassociated(fevent->rdataset))
+ dns_rdataset_disassociate(fevent->rdataset);
+ INSIST(fevent->sigrdataset == NULL);
+
+ isc_mem_put(res->mctx, fevent->rdataset, sizeof(*fevent->rdataset));
+
+ isc_event_free(&event);
+ dns_resolver_destroyfetch(&fetch);
+}
+
+void
+dns_resolver_prime(dns_resolver_t *res) {
+ isc_boolean_t want_priming = ISC_FALSE;
+ dns_rdataset_t *rdataset;
+ isc_result_t result;
+
+ REQUIRE(VALID_RESOLVER(res));
+ REQUIRE(res->frozen);
+
+ RTRACE("dns_resolver_prime");
+
+ LOCK(&res->lock);
+
+ if (!res->exiting && !res->priming) {
+ INSIST(res->primefetch == NULL);
+ res->priming = ISC_TRUE;
+ want_priming = ISC_TRUE;
+ }
+
+ UNLOCK(&res->lock);
+
+ if (want_priming) {
+ /*
+ * To avoid any possible recursive locking problems, we
+ * start the priming fetch like any other fetch, and holding
+ * no resolver locks. No one else will try to start it
+ * because we're the ones who set res->priming to true.
+ * Any other callers of dns_resolver_prime() while we're
+ * running will see that res->priming is already true and
+ * do nothing.
+ */
+ RTRACE("priming");
+ rdataset = isc_mem_get(res->mctx, sizeof(*rdataset));
+ if (rdataset == NULL) {
+ LOCK(&res->lock);
+ INSIST(res->priming);
+ INSIST(res->primefetch == NULL);
+ res->priming = ISC_FALSE;
+ UNLOCK(&res->lock);
+ return;
+ }
+ dns_rdataset_init(rdataset);
+ LOCK(&res->primelock);
+ result = dns_resolver_createfetch(res, dns_rootname,
+ dns_rdatatype_ns,
+ NULL, NULL, NULL, 0,
+ res->buckets[0].task,
+ prime_done,
+ res, rdataset, NULL,
+ &res->primefetch);
+ UNLOCK(&res->primelock);
+ if (result != ISC_R_SUCCESS) {
+ LOCK(&res->lock);
+ INSIST(res->priming);
+ res->priming = ISC_FALSE;
+ UNLOCK(&res->lock);
+ }
+ }
+}
+
+void
+dns_resolver_freeze(dns_resolver_t *res) {
+
+ /*
+ * Freeze resolver.
+ */
+
+ REQUIRE(VALID_RESOLVER(res));
+ REQUIRE(!res->frozen);
+
+ res->frozen = ISC_TRUE;
+}
+
+void
+dns_resolver_attach(dns_resolver_t *source, dns_resolver_t **targetp) {
+ REQUIRE(VALID_RESOLVER(source));
+ REQUIRE(targetp != NULL && *targetp == NULL);
+
+ RRTRACE(source, "attach");
+ LOCK(&source->lock);
+ REQUIRE(!source->exiting);
+
+ INSIST(source->references > 0);
+ source->references++;
+ INSIST(source->references != 0);
+ UNLOCK(&source->lock);
+
+ *targetp = source;
+}
+
+void
+dns_resolver_whenshutdown(dns_resolver_t *res, isc_task_t *task,
+ isc_event_t **eventp)
+{
+ isc_task_t *clone;
+ isc_event_t *event;
+
+ REQUIRE(VALID_RESOLVER(res));
+ REQUIRE(eventp != NULL);
+
+ event = *eventp;
+ *eventp = NULL;
+
+ LOCK(&res->lock);
+
+ if (res->exiting && res->activebuckets == 0) {
+ /*
+ * We're already shutdown. Send the event.
+ */
+ event->ev_sender = res;
+ isc_task_send(task, &event);
+ } else {
+ clone = NULL;
+ isc_task_attach(task, &clone);
+ event->ev_sender = clone;
+ ISC_LIST_APPEND(res->whenshutdown, event, ev_link);
+ }
+
+ UNLOCK(&res->lock);
+}
+
+void
+dns_resolver_shutdown(dns_resolver_t *res) {
+ unsigned int i;
+ fetchctx_t *fctx;
+ isc_socket_t *sock;
+
+ REQUIRE(VALID_RESOLVER(res));
+
+ RTRACE("shutdown");
+
+ LOCK(&res->lock);
+
+ if (!res->exiting) {
+ RTRACE("exiting");
+ res->exiting = ISC_TRUE;
+
+ for (i = 0; i < res->nbuckets; i++) {
+ LOCK(&res->buckets[i].lock);
+ for (fctx = ISC_LIST_HEAD(res->buckets[i].fctxs);
+ fctx != NULL;
+ fctx = ISC_LIST_NEXT(fctx, link))
+ fctx_shutdown(fctx);
+ if (res->dispatchv4 != NULL) {
+ sock = dns_dispatch_getsocket(res->dispatchv4);
+ isc_socket_cancel(sock, res->buckets[i].task,
+ ISC_SOCKCANCEL_ALL);
+ }
+ if (res->dispatchv6 != NULL) {
+ sock = dns_dispatch_getsocket(res->dispatchv6);
+ isc_socket_cancel(sock, res->buckets[i].task,
+ ISC_SOCKCANCEL_ALL);
+ }
+ res->buckets[i].exiting = ISC_TRUE;
+ if (ISC_LIST_EMPTY(res->buckets[i].fctxs)) {
+ INSIST(res->activebuckets > 0);
+ res->activebuckets--;
+ }
+ UNLOCK(&res->buckets[i].lock);
+ }
+ if (res->activebuckets == 0)
+ send_shutdown_events(res);
+ }
+
+ UNLOCK(&res->lock);
+}
+
+void
+dns_resolver_detach(dns_resolver_t **resp) {
+ dns_resolver_t *res;
+ isc_boolean_t need_destroy = ISC_FALSE;
+
+ REQUIRE(resp != NULL);
+ res = *resp;
+ REQUIRE(VALID_RESOLVER(res));
+
+ RTRACE("detach");
+
+ LOCK(&res->lock);
+
+ INSIST(res->references > 0);
+ res->references--;
+ if (res->references == 0) {
+ INSIST(res->exiting && res->activebuckets == 0);
+ need_destroy = ISC_TRUE;
+ }
+
+ UNLOCK(&res->lock);
+
+ if (need_destroy)
+ destroy(res);
+
+ *resp = NULL;
+}
+
+static inline isc_boolean_t
+fctx_match(fetchctx_t *fctx, dns_name_t *name, dns_rdatatype_t type,
+ unsigned int options)
+{
+ if (fctx->type != type || fctx->options != options)
+ return (ISC_FALSE);
+ return (dns_name_equal(&fctx->name, name));
+}
+
+static inline void
+log_fetch(dns_name_t *name, dns_rdatatype_t type) {
+ char namebuf[DNS_NAME_FORMATSIZE];
+ char typebuf[DNS_RDATATYPE_FORMATSIZE];
+ int level = ISC_LOG_DEBUG(1);
+
+ if (! isc_log_wouldlog(dns_lctx, level))
+ return;
+
+ dns_name_format(name, namebuf, sizeof(namebuf));
+ dns_rdatatype_format(type, typebuf, sizeof(typebuf));
+
+ isc_log_write(dns_lctx, DNS_LOGCATEGORY_RESOLVER,
+ DNS_LOGMODULE_RESOLVER, level,
+ "createfetch: %s %s", namebuf, typebuf);
+}
+
+isc_result_t
+dns_resolver_createfetch(dns_resolver_t *res, dns_name_t *name,
+ dns_rdatatype_t type,
+ dns_name_t *domain, dns_rdataset_t *nameservers,
+ dns_forwarders_t *forwarders,
+ unsigned int options, isc_task_t *task,
+ isc_taskaction_t action, void *arg,
+ dns_rdataset_t *rdataset,
+ dns_rdataset_t *sigrdataset,
+ dns_fetch_t **fetchp)
+{
+ dns_fetch_t *fetch;
+ fetchctx_t *fctx = NULL;
+ isc_result_t result;
+ unsigned int bucketnum;
+ isc_boolean_t new_fctx = ISC_FALSE;
+ isc_event_t *event;
+
+ UNUSED(forwarders);
+
+ REQUIRE(VALID_RESOLVER(res));
+ REQUIRE(res->frozen);
+ /* XXXRTH Check for meta type */
+ if (domain != NULL) {
+ REQUIRE(DNS_RDATASET_VALID(nameservers));
+ REQUIRE(nameservers->type == dns_rdatatype_ns);
+ } else
+ REQUIRE(nameservers == NULL);
+ REQUIRE(forwarders == NULL);
+ REQUIRE(!dns_rdataset_isassociated(rdataset));
+ REQUIRE(sigrdataset == NULL ||
+ !dns_rdataset_isassociated(sigrdataset));
+ REQUIRE(fetchp != NULL && *fetchp == NULL);
+
+ log_fetch(name, type);
+
+ /*
+ * XXXRTH use a mempool?
+ */
+ fetch = isc_mem_get(res->mctx, sizeof(*fetch));
+ if (fetch == NULL)
+ return (ISC_R_NOMEMORY);
+
+ bucketnum = dns_name_hash(name, ISC_FALSE) % res->nbuckets;
+
+ LOCK(&res->buckets[bucketnum].lock);
+
+ if (res->buckets[bucketnum].exiting) {
+ result = ISC_R_SHUTTINGDOWN;
+ goto unlock;
+ }
+
+ if ((options & DNS_FETCHOPT_UNSHARED) == 0) {
+ for (fctx = ISC_LIST_HEAD(res->buckets[bucketnum].fctxs);
+ fctx != NULL;
+ fctx = ISC_LIST_NEXT(fctx, link)) {
+ if (fctx_match(fctx, name, type, options))
+ break;
+ }
+ }
+
+ /*
+ * If we didn't have a fetch, would attach to a done fetch, this
+ * fetch has already cloned its results, or if the fetch has gone
+ * "idle" (no one was interested in it), we need to start a new
+ * fetch instead of joining with the existing one.
+ */
+ if (fctx == NULL ||
+ fctx->state == fetchstate_done ||
+ fctx->cloned ||
+ ISC_LIST_EMPTY(fctx->events)) {
+ fctx = NULL;
+ result = fctx_create(res, name, type, domain, nameservers,
+ options, bucketnum, &fctx);
+ if (result != ISC_R_SUCCESS)
+ goto unlock;
+ new_fctx = ISC_TRUE;
+ }
+
+ result = fctx_join(fctx, task, action, arg,
+ rdataset, sigrdataset, fetch);
+ if (new_fctx) {
+ if (result == ISC_R_SUCCESS) {
+ /*
+ * Launch this fctx.
+ */
+ event = &fctx->control_event;
+ ISC_EVENT_INIT(event, sizeof(*event), 0, NULL,
+ DNS_EVENT_FETCHCONTROL,
+ fctx_start, fctx, NULL,
+ NULL, NULL);
+ isc_task_send(res->buckets[bucketnum].task, &event);
+ } else {
+ /*
+ * We don't care about the result of fctx_destroy()
+ * since we know we're not exiting.
+ */
+ (void)fctx_destroy(fctx);
+ }
+ }
+
+ unlock:
+ UNLOCK(&res->buckets[bucketnum].lock);
+
+ if (result == ISC_R_SUCCESS) {
+ FTRACE("created");
+ *fetchp = fetch;
+ } else
+ isc_mem_put(res->mctx, fetch, sizeof(*fetch));
+
+ return (result);
+}
+
+void
+dns_resolver_cancelfetch(dns_fetch_t *fetch) {
+ fetchctx_t *fctx;
+ dns_resolver_t *res;
+ dns_fetchevent_t *event, *next_event;
+ isc_task_t *etask;
+
+ REQUIRE(DNS_FETCH_VALID(fetch));
+ fctx = fetch->private;
+ REQUIRE(VALID_FCTX(fctx));
+ res = fctx->res;
+
+ FTRACE("cancelfetch");
+
+ LOCK(&res->buckets[fctx->bucketnum].lock);
+
+ /*
+ * Find the completion event for this fetch (as opposed
+ * to those for other fetches that have joined the same
+ * fctx) and send it with result = ISC_R_CANCELED.
+ */
+ event = NULL;
+ if (fctx->state != fetchstate_done) {
+ for (event = ISC_LIST_HEAD(fctx->events);
+ event != NULL;
+ event = next_event) {
+ next_event = ISC_LIST_NEXT(event, ev_link);
+ if (event->fetch == fetch) {
+ ISC_LIST_UNLINK(fctx->events, event, ev_link);
+ break;
+ }
+ }
+ }
+ if (event != NULL) {
+ etask = event->ev_sender;
+ event->ev_sender = fctx;
+ event->result = ISC_R_CANCELED;
+ isc_task_sendanddetach(&etask, ISC_EVENT_PTR(&event));
+ }
+ /*
+ * The fctx continues running even if no fetches remain;
+ * the answer is still cached.
+ */
+
+ UNLOCK(&res->buckets[fctx->bucketnum].lock);
+}
+
+void
+dns_resolver_destroyfetch(dns_fetch_t **fetchp) {
+ dns_fetch_t *fetch;
+ dns_resolver_t *res;
+ dns_fetchevent_t *event, *next_event;
+ fetchctx_t *fctx;
+ unsigned int bucketnum;
+ isc_boolean_t bucket_empty = ISC_FALSE;
+
+ REQUIRE(fetchp != NULL);
+ fetch = *fetchp;
+ REQUIRE(DNS_FETCH_VALID(fetch));
+ fctx = fetch->private;
+ REQUIRE(VALID_FCTX(fctx));
+ res = fctx->res;
+
+ FTRACE("destroyfetch");
+
+ bucketnum = fctx->bucketnum;
+ LOCK(&res->buckets[bucketnum].lock);
+
+ /*
+ * Sanity check: the caller should have gotten its event before
+ * trying to destroy the fetch.
+ */
+ event = NULL;
+ if (fctx->state != fetchstate_done) {
+ for (event = ISC_LIST_HEAD(fctx->events);
+ event != NULL;
+ event = next_event) {
+ next_event = ISC_LIST_NEXT(event, ev_link);
+ RUNTIME_CHECK(event->fetch != fetch);
+ }
+ }
+
+ INSIST(fctx->references > 0);
+ fctx->references--;
+ if (fctx->references == 0) {
+ /*
+ * No one cares about the result of this fetch anymore.
+ */
+ if (fctx->pending == 0 && ISC_LIST_EMPTY(fctx->validators) &&
+ SHUTTINGDOWN(fctx)) {
+ /*
+ * This fctx is already shutdown; we were just
+ * waiting for the last reference to go away.
+ */
+ bucket_empty = fctx_destroy(fctx);
+ } else {
+ /*
+ * Initiate shutdown.
+ */
+ fctx_shutdown(fctx);
+ }
+ }
+
+ UNLOCK(&res->buckets[bucketnum].lock);
+
+ isc_mem_put(res->mctx, fetch, sizeof(*fetch));
+ *fetchp = NULL;
+
+ if (bucket_empty)
+ empty_bucket(res);
+}
+
+dns_dispatchmgr_t *
+dns_resolver_dispatchmgr(dns_resolver_t *resolver) {
+ REQUIRE(VALID_RESOLVER(resolver));
+ return (resolver->dispatchmgr);
+}
+
+dns_dispatch_t *
+dns_resolver_dispatchv4(dns_resolver_t *resolver) {
+ REQUIRE(VALID_RESOLVER(resolver));
+ return (resolver->dispatchv4);
+}
+
+dns_dispatch_t *
+dns_resolver_dispatchv6(dns_resolver_t *resolver) {
+ REQUIRE(VALID_RESOLVER(resolver));
+ return (resolver->dispatchv6);
+}
+
+isc_socketmgr_t *
+dns_resolver_socketmgr(dns_resolver_t *resolver) {
+ REQUIRE(VALID_RESOLVER(resolver));
+ return (resolver->socketmgr);
+}
+
+isc_taskmgr_t *
+dns_resolver_taskmgr(dns_resolver_t *resolver) {
+ REQUIRE(VALID_RESOLVER(resolver));
+ return (resolver->taskmgr);
+}
+
+isc_uint32_t
+dns_resolver_getlamettl(dns_resolver_t *resolver) {
+ REQUIRE(VALID_RESOLVER(resolver));
+ return (resolver->lame_ttl);
+}
+
+void
+dns_resolver_setlamettl(dns_resolver_t *resolver, isc_uint32_t lame_ttl) {
+ REQUIRE(VALID_RESOLVER(resolver));
+ resolver->lame_ttl = lame_ttl;
+}
+
+unsigned int
+dns_resolver_nrunning(dns_resolver_t *resolver) {
+ unsigned int n;
+ LOCK(&resolver->nlock);
+ n = resolver->nfctx;
+ UNLOCK(&resolver->nlock);
+ return (n);
+}
+
+isc_result_t
+dns_resolver_addalternate(dns_resolver_t *resolver, isc_sockaddr_t *alt,
+ dns_name_t *name, in_port_t port) {
+ alternate_t *a;
+ isc_result_t result;
+
+ REQUIRE(VALID_RESOLVER(resolver));
+ REQUIRE(!resolver->frozen);
+ REQUIRE((alt == NULL) ^ (name == NULL));
+
+ a = isc_mem_get(resolver->mctx, sizeof(*a));
+ if (a == NULL)
+ return (ISC_R_NOMEMORY);
+ if (alt != NULL) {
+ a->isaddress = ISC_TRUE;
+ a->_u.addr = *alt;
+ } else {
+ a->isaddress = ISC_FALSE;
+ a->_u._n.port = port;
+ dns_name_init(&a->_u._n.name, NULL);
+ result = dns_name_dup(name, resolver->mctx, &a->_u._n.name);
+ if (result != ISC_R_SUCCESS) {
+ isc_mem_put(resolver->mctx, a, sizeof(*a));
+ return (result);
+ }
+ }
+ ISC_LINK_INIT(a, link);
+ ISC_LIST_APPEND(resolver->alternates, a, link);
+
+ return (ISC_R_SUCCESS);
+}
+
+void
+dns_resolver_setudpsize(dns_resolver_t *resolver, isc_uint16_t udpsize) {
+ REQUIRE(VALID_RESOLVER(resolver));
+ resolver->udpsize = udpsize;
+}
+
+isc_uint16_t
+dns_resolver_getudpsize(dns_resolver_t *resolver) {
+ REQUIRE(VALID_RESOLVER(resolver));
+ return (resolver->udpsize);
+}
+
+static void
+free_algorithm(void *node, void *arg) {
+ unsigned char *algorithms = node;
+ isc_mem_t *mctx = arg;
+
+ isc_mem_put(mctx, algorithms, *algorithms);
+}
+
+void
+dns_resolver_reset_algorithms(dns_resolver_t *resolver) {
+
+ REQUIRE(VALID_RESOLVER(resolver));
+
+#if USE_ALGLOCK
+ RWLOCK(&resolver->alglock, isc_rwlocktype_write);
+#endif
+ if (resolver->algorithms != NULL)
+ dns_rbt_destroy(&resolver->algorithms);
+#if USE_ALGLOCK
+ RWUNLOCK(&resolver->alglock, isc_rwlocktype_write);
+#endif
+}
+
+isc_result_t
+dns_resolver_disable_algorithm(dns_resolver_t *resolver, dns_name_t *name,
+ unsigned int alg)
+{
+ unsigned int len, mask;
+ unsigned char *new;
+ unsigned char *algorithms;
+ isc_result_t result;
+ dns_rbtnode_t *node = NULL;
+
+ REQUIRE(VALID_RESOLVER(resolver));
+ if (alg > 255)
+ return (ISC_R_RANGE);
+
+#if USE_ALGLOCK
+ RWLOCK(&resolver->alglock, isc_rwlocktype_write);
+#endif
+ if (resolver->algorithms == NULL) {
+ result = dns_rbt_create(resolver->mctx, free_algorithm,
+ resolver->mctx, &resolver->algorithms);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup;
+ }
+
+ len = alg/8 + 2;
+ mask = 1 << (alg%8);
+
+ result = dns_rbt_addnode(resolver->algorithms, name, &node);
+
+ if (result == ISC_R_SUCCESS || result == ISC_R_EXISTS) {
+ algorithms = node->data;
+ if (algorithms == NULL || len > *algorithms) {
+ new = isc_mem_get(resolver->mctx, len);
+ if (new == NULL) {
+ result = ISC_R_NOMEMORY;
+ goto cleanup;
+ }
+ memset(new, 0, len);
+ if (algorithms != NULL)
+ memcpy(new, algorithms, *algorithms);
+ new[len-1] |= mask;
+ *new = len;
+ node->data = new;
+ if (algorithms != NULL)
+ isc_mem_put(resolver->mctx, algorithms,
+ *algorithms);
+ } else
+ algorithms[len-1] |= mask;
+ }
+ result = ISC_R_SUCCESS;
+ cleanup:
+#if USE_ALGLOCK
+ RWUNLOCK(&resolver->alglock, isc_rwlocktype_write);
+#endif
+ return (result);
+}
+
+isc_boolean_t
+dns_resolver_algorithm_supported(dns_resolver_t *resolver, dns_name_t *name,
+ unsigned int alg)
+{
+ unsigned int len, mask;
+ unsigned char *algorithms;
+ void *data = NULL;
+ isc_result_t result;
+ isc_boolean_t found = ISC_FALSE;
+
+ REQUIRE(VALID_RESOLVER(resolver));
+
+#if USE_ALGLOCK
+ RWLOCK(&resolver->alglock, isc_rwlocktype_read);
+#endif
+ if (resolver->algorithms == NULL)
+ goto unlock;
+ result = dns_rbt_findname(resolver->algorithms, name, 0, NULL, &data);
+ if (result == ISC_R_SUCCESS || result == DNS_R_PARTIALMATCH) {
+ len = alg/8 + 2;
+ mask = 1 << (alg%8);
+ algorithms = data;
+ if (len <= *algorithms && (algorithms[len-1] & mask) != 0)
+ found = ISC_TRUE;
+ }
+ unlock:
+#if USE_ALGLOCK
+ RWUNLOCK(&resolver->alglock, isc_rwlocktype_read);
+#endif
+ if (found)
+ return (ISC_FALSE);
+ return (dst_algorithm_supported(alg));
+}
+
+void
+dns_resolver_resetmustbesecure(dns_resolver_t *resolver) {
+
+ REQUIRE(VALID_RESOLVER(resolver));
+
+#if USE_MBSLOCK
+ RWLOCK(&resolver->mbslock, isc_rwlocktype_write);
+#endif
+ if (resolver->mustbesecure != NULL)
+ dns_rbt_destroy(&resolver->mustbesecure);
+#if USE_MBSLOCK
+ RWUNLOCK(&resolver->mbslock, isc_rwlocktype_write);
+#endif
+}
+
+static isc_boolean_t yes = ISC_TRUE, no = ISC_FALSE;
+
+isc_result_t
+dns_resolver_setmustbesecure(dns_resolver_t *resolver, dns_name_t *name,
+ isc_boolean_t value)
+{
+ isc_result_t result;
+
+ REQUIRE(VALID_RESOLVER(resolver));
+
+#if USE_MBSLOCK
+ RWLOCK(&resolver->mbslock, isc_rwlocktype_write);
+#endif
+ if (resolver->mustbesecure == NULL) {
+ result = dns_rbt_create(resolver->mctx, NULL, NULL,
+ &resolver->mustbesecure);
+ if (result != ISC_R_SUCCESS)
+ goto cleanup;
+ }
+ result = dns_rbt_addname(resolver->mustbesecure, name,
+ value ? &yes : &no);
+ cleanup:
+#if USE_MBSLOCK
+ RWUNLOCK(&resolver->mbslock, isc_rwlocktype_write);
+#endif
+ return (result);
+}
+
+isc_boolean_t
+dns_resolver_getmustbesecure(dns_resolver_t *resolver, dns_name_t *name) {
+ void *data = NULL;
+ isc_boolean_t value = ISC_FALSE;
+ isc_result_t result;
+
+ REQUIRE(VALID_RESOLVER(resolver));
+
+#if USE_MBSLOCK
+ RWLOCK(&resolver->mbslock, isc_rwlocktype_read);
+#endif
+ if (resolver->mustbesecure == NULL)
+ goto unlock;
+ result = dns_rbt_findname(resolver->mustbesecure, name, 0, NULL, &data);
+ if (result == ISC_R_SUCCESS || result == DNS_R_PARTIALMATCH)
+ value = *(isc_boolean_t*)data;
+ unlock:
+#if USE_MBSLOCK
+ RWUNLOCK(&resolver->mbslock, isc_rwlocktype_read);
+#endif
+ return (value);
+}