2014-07-16 00:26:02 +02:00
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/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
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/***
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This file is part of systemd.
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Copyright 2014 Lennart Poettering
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systemd is free software; you can redistribute it and/or modify it
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under the terms of the GNU Lesser General Public License as published by
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the Free Software Foundation; either version 2.1 of the License, or
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(at your option) any later version.
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systemd is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public License
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along with systemd; If not, see <http://www.gnu.org/licenses/>.
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***/
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2014-07-29 23:52:23 +02:00
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#include "af-list.h"
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2014-07-16 00:26:02 +02:00
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#include "resolved-dns-query.h"
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#include "resolved-dns-domain.h"
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2014-07-30 01:47:48 +02:00
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/* After how much time to repeat classic DNS requests */
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#define DNS_TRANSACTION_TIMEOUT_USEC (5 * USEC_PER_SEC)
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/* After how much time to repeat LLMNR requests, see RFC 4795 Section 7 */
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#define LLMNR_TRANSACTION_TIMEOUT_USEC (1 * USEC_PER_SEC)
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/* How long to wait for the query in total */
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2014-07-16 00:26:02 +02:00
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#define QUERY_TIMEOUT_USEC (30 * USEC_PER_SEC)
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2014-07-30 01:47:48 +02:00
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/* Maximum attempts to send DNS requests, across all DNS servers */
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#define DNS_TRANSACTION_ATTEMPTS_MAX 8
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/* Maximum attempts to send LLMNR requests, see RFC 4795 Section 2.7 */
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#define LLMNR_TRANSACTION_ATTEMPTS_MAX 3
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2014-07-16 22:09:00 +02:00
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#define CNAME_MAX 8
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2014-07-17 01:58:14 +02:00
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#define QUERIES_MAX 2048
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2014-07-16 22:09:00 +02:00
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2014-07-30 01:47:48 +02:00
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#define TRANSACTION_TIMEOUT_USEC(p) ((t)->scope->protocol == DNS_PROTOCOL_LLMNR ? LLMNR_TRANSACTION_TIMEOUT_USEC : DNS_TRANSACTION_TIMEOUT_USEC)
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#define TRANSACTION_ATTEMPTS_MAX(p) ((t)->scope->protocol == DNS_PROTOCOL_LLMNR ? LLMNR_TRANSACTION_ATTEMPTS_MAX : DNS_TRANSACTION_ATTEMPTS_MAX)
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2014-07-17 19:38:37 +02:00
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static int dns_query_transaction_go(DnsQueryTransaction *t);
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2014-07-16 00:26:02 +02:00
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DnsQueryTransaction* dns_query_transaction_free(DnsQueryTransaction *t) {
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2014-07-22 21:48:41 +02:00
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DnsQuery *q;
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2014-07-16 00:26:02 +02:00
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if (!t)
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return NULL;
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sd_event_source_unref(t->timeout_event_source);
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2014-07-16 20:15:47 +02:00
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2014-07-22 21:48:41 +02:00
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dns_question_unref(t->question);
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2014-07-16 20:15:47 +02:00
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dns_packet_unref(t->sent);
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dns_packet_unref(t->received);
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2014-07-22 21:48:41 +02:00
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dns_answer_unref(t->cached);
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2014-07-17 19:38:37 +02:00
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2014-07-29 14:24:02 +02:00
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dns_stream_free(t->stream);
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2014-07-16 00:26:02 +02:00
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2014-07-22 21:48:41 +02:00
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if (t->scope) {
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LIST_REMOVE(transactions_by_scope, t->scope->transactions, t);
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if (t->id != 0)
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hashmap_remove(t->scope->manager->dns_query_transactions, UINT_TO_PTR(t->id));
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2014-07-16 00:26:02 +02:00
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}
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2014-07-22 21:48:41 +02:00
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while ((q = set_steal_first(t->queries)))
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set_remove(q->transactions, t);
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set_free(t->queries);
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2014-07-16 00:26:02 +02:00
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free(t);
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return NULL;
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}
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DEFINE_TRIVIAL_CLEANUP_FUNC(DnsQueryTransaction*, dns_query_transaction_free);
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2014-07-22 21:48:41 +02:00
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static void dns_query_transaction_gc(DnsQueryTransaction *t) {
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assert(t);
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if (t->block_gc > 0)
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return;
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if (set_isempty(t->queries))
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dns_query_transaction_free(t);
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}
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static int dns_query_transaction_new(DnsQueryTransaction **ret, DnsScope *s, DnsQuestion *q) {
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2014-07-16 00:26:02 +02:00
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_cleanup_(dns_query_transaction_freep) DnsQueryTransaction *t = NULL;
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int r;
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2014-07-22 21:48:41 +02:00
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assert(ret);
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2014-07-16 00:26:02 +02:00
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assert(s);
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2014-07-22 21:48:41 +02:00
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assert(q);
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2014-07-16 00:26:02 +02:00
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2014-07-22 21:48:41 +02:00
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r = hashmap_ensure_allocated(&s->manager->dns_query_transactions, NULL, NULL);
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2014-07-16 00:26:02 +02:00
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if (r < 0)
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return r;
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t = new0(DnsQueryTransaction, 1);
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if (!t)
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return -ENOMEM;
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2014-07-22 21:48:41 +02:00
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t->question = dns_question_ref(q);
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2014-07-16 20:15:47 +02:00
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2014-07-16 00:26:02 +02:00
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do
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random_bytes(&t->id, sizeof(t->id));
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while (t->id == 0 ||
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2014-07-22 21:48:41 +02:00
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hashmap_get(s->manager->dns_query_transactions, UINT_TO_PTR(t->id)));
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2014-07-16 00:26:02 +02:00
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2014-07-22 21:48:41 +02:00
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r = hashmap_put(s->manager->dns_query_transactions, UINT_TO_PTR(t->id), t);
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2014-07-16 00:26:02 +02:00
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if (r < 0) {
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t->id = 0;
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return r;
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}
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LIST_PREPEND(transactions_by_scope, s->transactions, t);
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t->scope = s;
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if (ret)
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*ret = t;
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t = NULL;
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return 0;
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}
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2014-07-16 20:15:47 +02:00
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static void dns_query_transaction_stop(DnsQueryTransaction *t) {
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assert(t);
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t->timeout_event_source = sd_event_source_unref(t->timeout_event_source);
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2014-07-29 14:24:02 +02:00
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t->stream = dns_stream_free(t->stream);
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2014-07-16 20:15:47 +02:00
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}
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2014-07-22 21:48:41 +02:00
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void dns_query_transaction_complete(DnsQueryTransaction *t, DnsQueryState state) {
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DnsQuery *q;
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Iterator i;
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2014-07-16 00:26:02 +02:00
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assert(t);
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2014-07-17 19:38:37 +02:00
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assert(!IN_SET(state, DNS_QUERY_NULL, DNS_QUERY_PENDING));
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assert(IN_SET(t->state, DNS_QUERY_NULL, DNS_QUERY_PENDING));
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2014-07-16 00:26:02 +02:00
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2014-07-17 19:38:37 +02:00
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/* Note that this call might invalidate the query. Callers
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* should hence not attempt to access the query or transaction
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* after calling this function. */
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2014-07-16 00:26:02 +02:00
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2014-07-29 23:52:23 +02:00
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log_debug("Transaction on scope %s on %s/%s now complete with %s",
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dns_protocol_to_string(t->scope->protocol),
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t->scope->link ? t->scope->link->name : "*",
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t->scope->family == AF_UNSPEC ? "*" : af_to_name(t->scope->family),
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dns_query_state_to_string(state));
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2014-07-16 00:26:02 +02:00
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t->state = state;
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2014-07-17 19:38:37 +02:00
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dns_query_transaction_stop(t);
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2014-07-22 21:48:41 +02:00
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/* Notify all queries that are interested, but make sure the
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* transaction isn't freed while we are still looking at it */
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t->block_gc++;
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SET_FOREACH(q, t->queries, i)
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dns_query_ready(q);
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t->block_gc--;
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dns_query_transaction_gc(t);
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2014-07-16 20:15:47 +02:00
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}
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2014-07-29 14:24:02 +02:00
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static int on_stream_complete(DnsStream *s, int error) {
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_cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
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DnsQueryTransaction *t;
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2014-07-16 20:15:47 +02:00
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2014-07-29 14:24:02 +02:00
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assert(s);
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assert(s->transaction);
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2014-07-16 20:15:47 +02:00
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2014-07-29 14:24:02 +02:00
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/* Copy the data we care about out of the stream before we
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* destroy it. */
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t = s->transaction;
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p = dns_packet_ref(s->read_packet);
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2014-07-16 20:15:47 +02:00
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2014-07-29 14:24:02 +02:00
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t->stream = dns_stream_free(t->stream);
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2014-07-16 20:15:47 +02:00
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2014-07-29 14:24:02 +02:00
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if (error != 0) {
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dns_query_transaction_complete(t, DNS_QUERY_RESOURCES);
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return 0;
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2014-07-16 20:15:47 +02:00
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}
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2014-07-29 19:49:45 +02:00
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t->block_gc++;
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2014-07-29 14:24:02 +02:00
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dns_query_transaction_process_reply(t, p);
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2014-07-29 19:49:45 +02:00
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t->block_gc--;
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/* If the response wasn't useful, then complete the transition now */
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if (t->state == DNS_QUERY_PENDING)
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dns_query_transaction_complete(t, DNS_QUERY_INVALID_REPLY);
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2014-07-16 20:15:47 +02:00
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return 0;
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}
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2014-07-17 19:38:37 +02:00
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static int dns_query_transaction_open_tcp(DnsQueryTransaction *t) {
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2014-07-29 14:24:02 +02:00
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_cleanup_close_ int fd = -1;
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2014-07-16 20:15:47 +02:00
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int r;
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assert(t);
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2014-07-29 14:24:02 +02:00
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if (t->stream)
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return 0;
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2014-07-18 12:34:02 +02:00
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if (t->scope->protocol == DNS_PROTOCOL_DNS)
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2014-07-29 14:24:02 +02:00
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fd = dns_scope_tcp_socket(t->scope, AF_UNSPEC, NULL, 53);
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else if (t->scope->protocol == DNS_PROTOCOL_LLMNR) {
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2014-07-18 12:34:02 +02:00
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2014-07-29 19:49:45 +02:00
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/* When we already received a query to this (but it was truncated), send to its sender address */
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if (t->received)
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fd = dns_scope_tcp_socket(t->scope, t->received->family, &t->received->sender, t->received->sender_port);
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else {
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union in_addr_union address;
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int family;
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/* Otherwise, try to talk to the owner of a
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* the IP address, in case this is a reverse
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* PTR lookup */
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r = dns_question_extract_reverse_address(t->question, &family, &address);
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if (r < 0)
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return r;
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if (r == 0)
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return -EINVAL;
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fd = dns_scope_tcp_socket(t->scope, family, &address, 5355);
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}
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2014-07-29 14:24:02 +02:00
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} else
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return -EAFNOSUPPORT;
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2014-07-16 20:15:47 +02:00
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2014-07-29 14:24:02 +02:00
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if (fd < 0)
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return fd;
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2014-07-16 20:15:47 +02:00
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2014-07-29 14:24:02 +02:00
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r = dns_stream_new(t->scope->manager, &t->stream, t->scope->protocol, fd);
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if (r < 0)
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return r;
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2014-07-16 20:15:47 +02:00
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2014-07-29 14:24:02 +02:00
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fd = -1;
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r = dns_stream_write_packet(t->stream, t->sent);
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2014-07-16 20:15:47 +02:00
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if (r < 0) {
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2014-07-29 14:24:02 +02:00
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t->stream = dns_stream_free(t->stream);
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2014-07-16 20:15:47 +02:00
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return r;
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}
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2014-07-16 00:26:02 +02:00
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2014-07-29 14:24:02 +02:00
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t->received = dns_packet_unref(t->received);
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t->stream->complete = on_stream_complete;
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2014-07-29 19:49:45 +02:00
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t->stream->transaction = t;
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/* The interface index is difficult to determine if we are
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* connecting to the local host, hence fill this in right away
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* instead of determining it from the socket */
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if (t->scope->link)
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t->stream->ifindex = t->scope->link->ifindex;
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2014-07-29 14:24:02 +02:00
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2014-07-16 20:15:47 +02:00
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return 0;
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2014-07-16 00:26:02 +02:00
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}
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2014-07-22 21:48:41 +02:00
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void dns_query_transaction_process_reply(DnsQueryTransaction *t, DnsPacket *p) {
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2014-07-16 20:15:47 +02:00
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int r;
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2014-07-16 00:26:02 +02:00
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assert(t);
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assert(p);
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2014-07-17 19:38:37 +02:00
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assert(t->state == DNS_QUERY_PENDING);
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2014-07-16 00:26:02 +02:00
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2014-07-17 19:38:37 +02:00
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/* Note that this call might invalidate the query. Callers
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* should hence not attempt to access the query or transaction
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* after calling this function. */
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2014-07-16 20:15:47 +02:00
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2014-07-29 14:24:02 +02:00
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if (t->scope->protocol == DNS_PROTOCOL_LLMNR) {
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assert(t->scope->link);
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/* For LLMNR we will not accept any packets from other
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* interfaces */
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if (p->ifindex != t->scope->link->ifindex)
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return;
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if (p->family != t->scope->family)
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return;
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2014-07-29 19:50:28 +02:00
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/* Tentative replies shall be discarded, see RFC 4795,
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* 2.1.1 */
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if (DNS_PACKET_T(p))
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return;
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2014-07-29 14:24:02 +02:00
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}
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if (t->scope->protocol == DNS_PROTOCOL_DNS) {
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/* For DNS we are fine with accepting packets on any
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* interface, but the source IP address must be one of
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* a valid DNS server */
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if (!dns_scope_good_dns_server(t->scope, p->family, &p->sender))
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return;
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if (p->sender_port != 53)
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return;
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}
|
|
|
|
|
2014-07-16 20:15:47 +02:00
|
|
|
if (t->received != p) {
|
|
|
|
dns_packet_unref(t->received);
|
|
|
|
t->received = dns_packet_ref(p);
|
|
|
|
}
|
|
|
|
|
2014-07-29 14:24:02 +02:00
|
|
|
if (p->ipproto == IPPROTO_TCP) {
|
2014-07-16 20:15:47 +02:00
|
|
|
if (DNS_PACKET_TC(p)) {
|
|
|
|
/* Truncated via TCP? Somebody must be fucking with us */
|
2014-07-17 19:38:37 +02:00
|
|
|
dns_query_transaction_complete(t, DNS_QUERY_INVALID_REPLY);
|
2014-07-16 20:15:47 +02:00
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (DNS_PACKET_ID(p) != t->id) {
|
|
|
|
/* Not the reply to our query? Somebody must be fucking with us */
|
2014-07-17 19:38:37 +02:00
|
|
|
dns_query_transaction_complete(t, DNS_QUERY_INVALID_REPLY);
|
2014-07-16 20:15:47 +02:00
|
|
|
return;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
if (DNS_PACKET_TC(p)) {
|
|
|
|
/* Response was truncated, let's try again with good old TCP */
|
2014-07-17 19:38:37 +02:00
|
|
|
r = dns_query_transaction_open_tcp(t);
|
2014-07-16 22:09:00 +02:00
|
|
|
if (r == -ESRCH) {
|
|
|
|
/* No servers found? Damn! */
|
2014-07-17 19:38:37 +02:00
|
|
|
dns_query_transaction_complete(t, DNS_QUERY_NO_SERVERS);
|
2014-07-16 22:09:00 +02:00
|
|
|
return;
|
|
|
|
}
|
2014-07-16 20:15:47 +02:00
|
|
|
if (r < 0) {
|
2014-07-29 14:24:02 +02:00
|
|
|
/* On LLMNR, if we cannot connect to the host,
|
|
|
|
* we immediately give up */
|
|
|
|
if (t->scope->protocol == DNS_PROTOCOL_LLMNR) {
|
|
|
|
dns_query_transaction_complete(t, DNS_QUERY_RESOURCES);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* On DNS, couldn't send? Try immediately again, with a new server */
|
2014-07-16 22:09:00 +02:00
|
|
|
dns_scope_next_dns_server(t->scope);
|
|
|
|
|
2014-07-17 19:38:37 +02:00
|
|
|
r = dns_query_transaction_go(t);
|
2014-07-16 22:09:00 +02:00
|
|
|
if (r < 0) {
|
2014-07-17 19:38:37 +02:00
|
|
|
dns_query_transaction_complete(t, DNS_QUERY_RESOURCES);
|
2014-07-16 22:09:00 +02:00
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
2014-07-16 20:15:47 +02:00
|
|
|
return;
|
|
|
|
}
|
|
|
|
}
|
2014-07-16 00:26:02 +02:00
|
|
|
|
2014-07-17 19:38:37 +02:00
|
|
|
/* Parse and update the cache */
|
2014-07-22 21:48:41 +02:00
|
|
|
r = dns_packet_extract(p);
|
2014-07-17 19:38:37 +02:00
|
|
|
if (r < 0) {
|
|
|
|
dns_query_transaction_complete(t, DNS_QUERY_INVALID_REPLY);
|
|
|
|
return;
|
2014-07-23 01:59:36 +02:00
|
|
|
}
|
|
|
|
|
2014-07-30 01:46:27 +02:00
|
|
|
/* According to RFC 4795, section 2.9. only the RRs from the answer section shall be cached */
|
|
|
|
dns_cache_put(&t->scope->cache, p->question, DNS_PACKET_RCODE(p), p->answer, DNS_PACKET_ANCOUNT(p), 0);
|
2014-07-17 19:38:37 +02:00
|
|
|
|
2014-07-16 03:28:18 +02:00
|
|
|
if (DNS_PACKET_RCODE(p) == DNS_RCODE_SUCCESS)
|
2014-07-17 19:38:37 +02:00
|
|
|
dns_query_transaction_complete(t, DNS_QUERY_SUCCESS);
|
2014-07-16 03:28:18 +02:00
|
|
|
else
|
2014-07-17 19:38:37 +02:00
|
|
|
dns_query_transaction_complete(t, DNS_QUERY_FAILURE);
|
2014-07-16 00:26:02 +02:00
|
|
|
}
|
|
|
|
|
|
|
|
static int on_transaction_timeout(sd_event_source *s, usec_t usec, void *userdata) {
|
|
|
|
DnsQueryTransaction *t = userdata;
|
|
|
|
int r;
|
|
|
|
|
|
|
|
assert(s);
|
|
|
|
assert(t);
|
|
|
|
|
|
|
|
/* Timeout reached? Try again, with a new server */
|
|
|
|
dns_scope_next_dns_server(t->scope);
|
|
|
|
|
2014-07-17 19:38:37 +02:00
|
|
|
r = dns_query_transaction_go(t);
|
2014-07-16 00:26:02 +02:00
|
|
|
if (r < 0)
|
2014-07-17 19:38:37 +02:00
|
|
|
dns_query_transaction_complete(t, DNS_QUERY_RESOURCES);
|
2014-07-16 00:26:02 +02:00
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2014-07-16 20:15:47 +02:00
|
|
|
static int dns_query_make_packet(DnsQueryTransaction *t) {
|
2014-07-16 00:26:02 +02:00
|
|
|
_cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
|
2014-07-18 12:34:02 +02:00
|
|
|
unsigned n, added = 0;
|
2014-07-16 00:26:02 +02:00
|
|
|
int r;
|
|
|
|
|
|
|
|
assert(t);
|
|
|
|
|
2014-07-16 20:15:47 +02:00
|
|
|
if (t->sent)
|
2014-07-16 00:26:02 +02:00
|
|
|
return 0;
|
|
|
|
|
2014-07-18 12:34:02 +02:00
|
|
|
r = dns_packet_new_query(&p, t->scope->protocol, 0);
|
2014-07-16 00:26:02 +02:00
|
|
|
if (r < 0)
|
|
|
|
return r;
|
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
for (n = 0; n < t->question->n_keys; n++) {
|
|
|
|
r = dns_scope_good_key(t->scope, t->question->keys[n]);
|
2014-07-18 12:34:02 +02:00
|
|
|
if (r < 0)
|
|
|
|
return r;
|
|
|
|
if (r == 0)
|
|
|
|
continue;
|
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
r = dns_packet_append_key(p, t->question->keys[n], NULL);
|
2014-07-16 00:26:02 +02:00
|
|
|
if (r < 0)
|
|
|
|
return r;
|
2014-07-18 12:34:02 +02:00
|
|
|
|
|
|
|
added++;
|
2014-07-16 00:26:02 +02:00
|
|
|
}
|
|
|
|
|
2014-07-18 12:34:02 +02:00
|
|
|
if (added <= 0)
|
|
|
|
return -EDOM;
|
|
|
|
|
|
|
|
DNS_PACKET_HEADER(p)->qdcount = htobe16(added);
|
2014-07-16 00:26:02 +02:00
|
|
|
DNS_PACKET_HEADER(p)->id = t->id;
|
|
|
|
|
2014-07-16 20:15:47 +02:00
|
|
|
t->sent = p;
|
|
|
|
p = NULL;
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2014-07-17 19:38:37 +02:00
|
|
|
static int dns_query_transaction_go(DnsQueryTransaction *t) {
|
2014-07-30 01:47:48 +02:00
|
|
|
bool had_stream;
|
2014-07-16 20:15:47 +02:00
|
|
|
int r;
|
|
|
|
|
|
|
|
assert(t);
|
|
|
|
|
2014-07-30 01:47:48 +02:00
|
|
|
had_stream = !!t->stream;
|
|
|
|
|
2014-07-16 20:15:47 +02:00
|
|
|
dns_query_transaction_stop(t);
|
|
|
|
|
2014-07-29 23:52:23 +02:00
|
|
|
log_debug("Beginning transaction on scope %s on %s/%s",
|
|
|
|
dns_protocol_to_string(t->scope->protocol),
|
|
|
|
t->scope->link ? t->scope->link->name : "*",
|
|
|
|
t->scope->family == AF_UNSPEC ? "*" : af_to_name(t->scope->family));
|
|
|
|
|
2014-07-30 01:47:48 +02:00
|
|
|
if (t->n_attempts >= TRANSACTION_ATTEMPTS_MAX(t)) {
|
|
|
|
dns_query_transaction_complete(t, DNS_QUERY_ATTEMPTS_MAX);
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (t->scope->protocol == DNS_PROTOCOL_LLMNR && had_stream) {
|
|
|
|
/* If we already tried via a stream, then we don't
|
|
|
|
* retry on LLMNR. See RFC 4795, Section 2.7. */
|
2014-07-17 19:38:37 +02:00
|
|
|
dns_query_transaction_complete(t, DNS_QUERY_ATTEMPTS_MAX);
|
2014-07-16 20:15:47 +02:00
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2014-07-17 19:38:37 +02:00
|
|
|
t->n_attempts++;
|
|
|
|
t->received = dns_packet_unref(t->received);
|
2014-07-22 21:48:41 +02:00
|
|
|
t->cached = dns_answer_unref(t->cached);
|
2014-07-23 00:57:25 +02:00
|
|
|
t->cached_rcode = 0;
|
2014-07-17 19:38:37 +02:00
|
|
|
|
|
|
|
/* First, let's try the cache */
|
|
|
|
dns_cache_prune(&t->scope->cache);
|
2014-07-23 00:57:25 +02:00
|
|
|
r = dns_cache_lookup(&t->scope->cache, t->question, &t->cached_rcode, &t->cached);
|
2014-07-16 20:15:47 +02:00
|
|
|
if (r < 0)
|
|
|
|
return r;
|
2014-07-17 19:38:37 +02:00
|
|
|
if (r > 0) {
|
2014-07-23 00:57:25 +02:00
|
|
|
if (t->cached_rcode == DNS_RCODE_SUCCESS)
|
|
|
|
dns_query_transaction_complete(t, DNS_QUERY_SUCCESS);
|
|
|
|
else
|
|
|
|
dns_query_transaction_complete(t, DNS_QUERY_FAILURE);
|
2014-07-17 19:38:37 +02:00
|
|
|
return 0;
|
|
|
|
}
|
2014-07-16 20:15:47 +02:00
|
|
|
|
2014-07-17 19:38:37 +02:00
|
|
|
/* Otherwise, we need to ask the network */
|
|
|
|
r = dns_query_make_packet(t);
|
2014-07-18 12:34:02 +02:00
|
|
|
if (r == -EDOM) {
|
|
|
|
/* Not the right request to make on this network?
|
|
|
|
* (i.e. an A request made on IPv6 or an AAAA request
|
|
|
|
* made on IPv4, on LLMNR or mDNS.) */
|
|
|
|
dns_query_transaction_complete(t, DNS_QUERY_NO_SERVERS);
|
|
|
|
return 0;
|
|
|
|
}
|
2014-07-17 19:38:37 +02:00
|
|
|
if (r < 0)
|
|
|
|
return r;
|
2014-07-16 22:09:00 +02:00
|
|
|
|
2014-07-29 19:49:45 +02:00
|
|
|
if (t->scope->protocol == DNS_PROTOCOL_LLMNR &&
|
|
|
|
(dns_question_endswith(t->question, "in-addr.arpa") > 0 ||
|
|
|
|
dns_question_endswith(t->question, "ip6.arpa") > 0)) {
|
|
|
|
|
|
|
|
/* RFC 4795, Section 2.4. says reverse lookups shall
|
|
|
|
* always be made via TCP on LLMNR */
|
2014-07-17 19:38:37 +02:00
|
|
|
r = dns_query_transaction_open_tcp(t);
|
2014-07-29 19:49:45 +02:00
|
|
|
} else {
|
|
|
|
/* Try via UDP, and if that fails due to large size try via TCP */
|
|
|
|
r = dns_scope_send(t->scope, t->sent);
|
|
|
|
if (r == -EMSGSIZE)
|
|
|
|
r = dns_query_transaction_open_tcp(t);
|
|
|
|
}
|
2014-07-16 20:15:47 +02:00
|
|
|
if (r == -ESRCH) {
|
2014-07-18 12:34:02 +02:00
|
|
|
/* No servers to send this to? */
|
2014-07-17 19:38:37 +02:00
|
|
|
dns_query_transaction_complete(t, DNS_QUERY_NO_SERVERS);
|
2014-07-16 20:15:47 +02:00
|
|
|
return 0;
|
|
|
|
}
|
2014-07-16 00:26:02 +02:00
|
|
|
if (r < 0) {
|
|
|
|
/* Couldn't send? Try immediately again, with a new server */
|
|
|
|
dns_scope_next_dns_server(t->scope);
|
|
|
|
|
2014-07-17 19:38:37 +02:00
|
|
|
return dns_query_transaction_go(t);
|
2014-07-16 00:26:02 +02:00
|
|
|
}
|
|
|
|
|
2014-07-30 01:47:48 +02:00
|
|
|
r = sd_event_add_time(t->scope->manager->event, &t->timeout_event_source, CLOCK_MONOTONIC, now(CLOCK_MONOTONIC) + TRANSACTION_TIMEOUT_USEC(t), 0, on_transaction_timeout, t);
|
2014-07-16 20:15:47 +02:00
|
|
|
if (r < 0)
|
|
|
|
return r;
|
2014-07-16 00:26:02 +02:00
|
|
|
|
2014-07-17 19:38:37 +02:00
|
|
|
t->state = DNS_QUERY_PENDING;
|
2014-07-16 20:15:47 +02:00
|
|
|
return 1;
|
2014-07-16 00:26:02 +02:00
|
|
|
}
|
|
|
|
|
|
|
|
DnsQuery *dns_query_free(DnsQuery *q) {
|
2014-07-22 21:48:41 +02:00
|
|
|
DnsQueryTransaction *t;
|
2014-07-16 00:26:02 +02:00
|
|
|
|
|
|
|
if (!q)
|
|
|
|
return NULL;
|
|
|
|
|
|
|
|
sd_bus_message_unref(q->request);
|
2014-07-17 19:38:37 +02:00
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
dns_question_unref(q->question);
|
|
|
|
dns_answer_unref(q->answer);
|
2014-07-17 19:38:37 +02:00
|
|
|
|
2014-07-16 00:26:02 +02:00
|
|
|
sd_event_source_unref(q->timeout_event_source);
|
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
while ((t = set_steal_first(q->transactions))) {
|
|
|
|
set_remove(t->queries, q);
|
|
|
|
dns_query_transaction_gc(t);
|
|
|
|
}
|
|
|
|
|
|
|
|
set_free(q->transactions);
|
2014-07-16 00:26:02 +02:00
|
|
|
|
2014-07-17 01:58:14 +02:00
|
|
|
if (q->manager) {
|
2014-07-16 00:26:02 +02:00
|
|
|
LIST_REMOVE(queries, q->manager->dns_queries, q);
|
2014-07-17 01:58:14 +02:00
|
|
|
q->manager->n_dns_queries--;
|
|
|
|
}
|
2014-07-16 00:26:02 +02:00
|
|
|
|
|
|
|
free(q);
|
|
|
|
|
|
|
|
return NULL;
|
|
|
|
}
|
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
int dns_query_new(Manager *m, DnsQuery **ret, DnsQuestion *question) {
|
2014-07-16 00:26:02 +02:00
|
|
|
_cleanup_(dns_query_freep) DnsQuery *q = NULL;
|
2014-07-22 21:48:41 +02:00
|
|
|
unsigned i;
|
|
|
|
int r;
|
2014-07-16 00:26:02 +02:00
|
|
|
|
|
|
|
assert(m);
|
2014-07-22 21:48:41 +02:00
|
|
|
assert(question);
|
2014-07-16 00:26:02 +02:00
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
r = dns_question_is_valid(question);
|
|
|
|
if (r < 0)
|
|
|
|
return r;
|
2014-07-16 00:26:02 +02:00
|
|
|
|
2014-07-17 01:58:14 +02:00
|
|
|
if (m->n_dns_queries >= QUERIES_MAX)
|
|
|
|
return -EBUSY;
|
|
|
|
|
2014-07-16 00:26:02 +02:00
|
|
|
q = new0(DnsQuery, 1);
|
|
|
|
if (!q)
|
|
|
|
return -ENOMEM;
|
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
q->question = dns_question_ref(question);
|
2014-07-17 19:38:37 +02:00
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
for (i = 0; i < question->n_keys; i++) {
|
2014-07-17 19:38:37 +02:00
|
|
|
log_debug("Looking up RR for %s %s %s",
|
2014-07-22 21:48:41 +02:00
|
|
|
strna(dns_class_to_string(question->keys[i]->class)),
|
|
|
|
strna(dns_type_to_string(question->keys[i]->type)),
|
|
|
|
DNS_RESOURCE_KEY_NAME(question->keys[i]));
|
2014-07-16 00:26:02 +02:00
|
|
|
}
|
|
|
|
|
|
|
|
LIST_PREPEND(queries, m->dns_queries, q);
|
2014-07-17 01:58:14 +02:00
|
|
|
m->n_dns_queries++;
|
2014-07-16 00:26:02 +02:00
|
|
|
q->manager = m;
|
|
|
|
|
2014-07-16 22:09:00 +02:00
|
|
|
if (ret)
|
|
|
|
*ret = q;
|
|
|
|
q = NULL;
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void dns_query_stop(DnsQuery *q) {
|
2014-07-22 21:48:41 +02:00
|
|
|
DnsQueryTransaction *t;
|
|
|
|
|
2014-07-16 22:09:00 +02:00
|
|
|
assert(q);
|
|
|
|
|
|
|
|
q->timeout_event_source = sd_event_source_unref(q->timeout_event_source);
|
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
while ((t = set_steal_first(q->transactions))) {
|
|
|
|
set_remove(t->queries, q);
|
|
|
|
dns_query_transaction_gc(t);
|
|
|
|
}
|
2014-07-16 22:09:00 +02:00
|
|
|
}
|
|
|
|
|
2014-07-17 19:38:37 +02:00
|
|
|
static void dns_query_complete(DnsQuery *q, DnsQueryState state) {
|
2014-07-16 22:09:00 +02:00
|
|
|
assert(q);
|
2014-07-17 19:38:37 +02:00
|
|
|
assert(!IN_SET(state, DNS_QUERY_NULL, DNS_QUERY_PENDING));
|
|
|
|
assert(IN_SET(q->state, DNS_QUERY_NULL, DNS_QUERY_PENDING));
|
2014-07-16 22:09:00 +02:00
|
|
|
|
2014-07-17 19:38:37 +02:00
|
|
|
/* Note that this call might invalidate the query. Callers
|
|
|
|
* should hence not attempt to access the query or transaction
|
|
|
|
* after calling this function. */
|
2014-07-16 22:09:00 +02:00
|
|
|
|
|
|
|
q->state = state;
|
|
|
|
|
2014-07-17 19:38:37 +02:00
|
|
|
dns_query_stop(q);
|
|
|
|
if (q->complete)
|
|
|
|
q->complete(q);
|
2014-07-16 22:09:00 +02:00
|
|
|
}
|
|
|
|
|
|
|
|
static int on_query_timeout(sd_event_source *s, usec_t usec, void *userdata) {
|
|
|
|
DnsQuery *q = userdata;
|
|
|
|
|
|
|
|
assert(s);
|
|
|
|
assert(q);
|
|
|
|
|
2014-07-17 19:38:37 +02:00
|
|
|
dns_query_complete(q, DNS_QUERY_TIMEOUT);
|
2014-07-16 22:09:00 +02:00
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2014-07-23 01:59:36 +02:00
|
|
|
static int dns_query_add_transaction(DnsQuery *q, DnsScope *s, DnsResourceKey *key) {
|
|
|
|
_cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
|
2014-07-22 21:48:41 +02:00
|
|
|
DnsQueryTransaction *t;
|
|
|
|
int r;
|
|
|
|
|
|
|
|
assert(q);
|
|
|
|
|
|
|
|
r = set_ensure_allocated(&q->transactions, NULL, NULL);
|
|
|
|
if (r < 0)
|
|
|
|
return r;
|
|
|
|
|
2014-07-23 01:59:36 +02:00
|
|
|
if (key) {
|
|
|
|
question = dns_question_new(1);
|
|
|
|
if (!question)
|
|
|
|
return -ENOMEM;
|
|
|
|
|
|
|
|
r = dns_question_add(question, key);
|
|
|
|
if (r < 0)
|
|
|
|
return r;
|
|
|
|
} else
|
|
|
|
question = dns_question_ref(q->question);
|
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
LIST_FOREACH(transactions_by_scope, t, s->transactions)
|
2014-07-23 01:59:36 +02:00
|
|
|
if (dns_question_is_superset(t->question, question))
|
2014-07-22 21:48:41 +02:00
|
|
|
break;
|
|
|
|
|
|
|
|
if (!t) {
|
2014-07-23 01:59:36 +02:00
|
|
|
r = dns_query_transaction_new(&t, s, question);
|
2014-07-22 21:48:41 +02:00
|
|
|
if (r < 0)
|
|
|
|
return r;
|
|
|
|
}
|
|
|
|
|
|
|
|
r = set_ensure_allocated(&t->queries, NULL, NULL);
|
|
|
|
if (r < 0)
|
|
|
|
goto fail;
|
|
|
|
|
|
|
|
r = set_put(t->queries, q);
|
|
|
|
if (r < 0)
|
|
|
|
goto fail;
|
|
|
|
|
|
|
|
r = set_put(q->transactions, t);
|
|
|
|
if (r < 0) {
|
|
|
|
set_remove(t->queries, q);
|
|
|
|
goto fail;
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
fail:
|
|
|
|
dns_query_transaction_gc(t);
|
|
|
|
return r;
|
|
|
|
}
|
|
|
|
|
2014-07-23 01:59:36 +02:00
|
|
|
static int dns_query_add_transaction_split(DnsQuery *q, DnsScope *s) {
|
|
|
|
int r;
|
|
|
|
|
|
|
|
assert(q);
|
|
|
|
assert(s);
|
|
|
|
|
|
|
|
if (s->protocol == DNS_PROTOCOL_MDNS) {
|
|
|
|
r = dns_query_add_transaction(q, s, NULL);
|
|
|
|
if (r < 0)
|
|
|
|
return r;
|
|
|
|
} else {
|
|
|
|
unsigned i;
|
|
|
|
|
|
|
|
/* On DNS and LLMNR we can only send a single
|
|
|
|
* question per datagram, hence issue multiple
|
|
|
|
* transactions. */
|
|
|
|
|
|
|
|
for (i = 0; i < q->question->n_keys; i++) {
|
|
|
|
r = dns_query_add_transaction(q, s, q->question->keys[i]);
|
|
|
|
if (r < 0)
|
|
|
|
return r;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2014-07-17 19:38:37 +02:00
|
|
|
int dns_query_go(DnsQuery *q) {
|
2014-07-16 22:09:00 +02:00
|
|
|
DnsScopeMatch found = DNS_SCOPE_NO;
|
|
|
|
DnsScope *s, *first = NULL;
|
|
|
|
DnsQueryTransaction *t;
|
2014-07-22 21:48:41 +02:00
|
|
|
const char *name;
|
|
|
|
Iterator i;
|
2014-07-16 22:09:00 +02:00
|
|
|
int r;
|
|
|
|
|
|
|
|
assert(q);
|
|
|
|
|
|
|
|
if (q->state != DNS_QUERY_NULL)
|
|
|
|
return 0;
|
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
assert(q->question);
|
|
|
|
assert(q->question->n_keys > 0);
|
|
|
|
|
|
|
|
name = DNS_RESOURCE_KEY_NAME(q->question->keys[0]);
|
2014-07-16 22:09:00 +02:00
|
|
|
|
|
|
|
LIST_FOREACH(scopes, s, q->manager->dns_scopes) {
|
2014-07-16 00:26:02 +02:00
|
|
|
DnsScopeMatch match;
|
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
match = dns_scope_good_domain(s, name);
|
2014-07-16 00:26:02 +02:00
|
|
|
if (match < 0)
|
|
|
|
return match;
|
|
|
|
|
|
|
|
if (match == DNS_SCOPE_NO)
|
|
|
|
continue;
|
|
|
|
|
|
|
|
found = match;
|
|
|
|
|
|
|
|
if (match == DNS_SCOPE_YES) {
|
|
|
|
first = s;
|
|
|
|
break;
|
|
|
|
} else {
|
|
|
|
assert(match == DNS_SCOPE_MAYBE);
|
|
|
|
|
|
|
|
if (!first)
|
|
|
|
first = s;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
if (found == DNS_SCOPE_NO)
|
2014-07-16 22:09:00 +02:00
|
|
|
return -ESRCH;
|
2014-07-16 00:26:02 +02:00
|
|
|
|
2014-07-23 01:59:36 +02:00
|
|
|
r = dns_query_add_transaction_split(q, first);
|
2014-07-16 00:26:02 +02:00
|
|
|
if (r < 0)
|
|
|
|
return r;
|
|
|
|
|
|
|
|
LIST_FOREACH(scopes, s, first->scopes_next) {
|
|
|
|
DnsScopeMatch match;
|
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
match = dns_scope_good_domain(s, name);
|
2014-07-16 00:26:02 +02:00
|
|
|
if (match < 0)
|
|
|
|
return match;
|
|
|
|
|
|
|
|
if (match != found)
|
|
|
|
continue;
|
|
|
|
|
2014-07-23 01:59:36 +02:00
|
|
|
r = dns_query_add_transaction_split(q, s);
|
2014-07-16 00:26:02 +02:00
|
|
|
if (r < 0)
|
|
|
|
return r;
|
|
|
|
}
|
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
q->answer = dns_answer_unref(q->answer);
|
|
|
|
q->answer_ifindex = 0;
|
|
|
|
q->answer_rcode = 0;
|
2014-07-16 00:26:02 +02:00
|
|
|
|
|
|
|
r = sd_event_add_time(q->manager->event, &q->timeout_event_source, CLOCK_MONOTONIC, now(CLOCK_MONOTONIC) + QUERY_TIMEOUT_USEC, 0, on_query_timeout, q);
|
|
|
|
if (r < 0)
|
|
|
|
goto fail;
|
|
|
|
|
2014-07-17 19:38:37 +02:00
|
|
|
q->state = DNS_QUERY_PENDING;
|
2014-07-22 21:48:41 +02:00
|
|
|
q->block_ready++;
|
2014-07-16 00:26:02 +02:00
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
SET_FOREACH(t, q->transactions, i) {
|
|
|
|
if (t->state == DNS_QUERY_NULL) {
|
|
|
|
r = dns_query_transaction_go(t);
|
|
|
|
if (r < 0)
|
|
|
|
goto fail;
|
|
|
|
}
|
2014-07-16 00:26:02 +02:00
|
|
|
}
|
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
q->block_ready--;
|
|
|
|
dns_query_ready(q);
|
2014-07-17 19:38:37 +02:00
|
|
|
|
2014-07-16 22:09:00 +02:00
|
|
|
return 1;
|
2014-07-16 00:26:02 +02:00
|
|
|
|
|
|
|
fail:
|
2014-07-16 22:09:00 +02:00
|
|
|
dns_query_stop(q);
|
2014-07-16 00:26:02 +02:00
|
|
|
return r;
|
|
|
|
}
|
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
void dns_query_ready(DnsQuery *q) {
|
2014-07-16 00:26:02 +02:00
|
|
|
DnsQueryTransaction *t;
|
2014-07-16 20:15:47 +02:00
|
|
|
DnsQueryState state = DNS_QUERY_NO_SERVERS;
|
2014-07-23 01:59:36 +02:00
|
|
|
_cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL;
|
|
|
|
int rcode = 0;
|
|
|
|
DnsScope *scope = NULL;
|
2014-07-22 21:48:41 +02:00
|
|
|
Iterator i;
|
2014-07-16 00:26:02 +02:00
|
|
|
|
|
|
|
assert(q);
|
2014-07-17 19:38:37 +02:00
|
|
|
assert(IN_SET(q->state, DNS_QUERY_NULL, DNS_QUERY_PENDING));
|
2014-07-16 00:26:02 +02:00
|
|
|
|
2014-07-17 19:38:37 +02:00
|
|
|
/* Note that this call might invalidate the query. Callers
|
|
|
|
* should hence not attempt to access the query or transaction
|
2014-07-22 21:48:41 +02:00
|
|
|
* after calling this function, unless the block_ready
|
2014-07-17 19:38:37 +02:00
|
|
|
* counter was explicitly bumped before doing so. */
|
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
if (q->block_ready > 0)
|
2014-07-16 00:26:02 +02:00
|
|
|
return;
|
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
SET_FOREACH(t, q->transactions, i) {
|
2014-07-16 00:26:02 +02:00
|
|
|
|
2014-07-23 01:59:36 +02:00
|
|
|
/* If we found a successful answer, ignore all answers from other scopes */
|
|
|
|
if (state == DNS_QUERY_SUCCESS && t->scope != scope)
|
|
|
|
continue;
|
|
|
|
|
2014-07-16 00:26:02 +02:00
|
|
|
/* One of the transactions is still going on, let's wait for it */
|
2014-07-16 22:09:00 +02:00
|
|
|
if (t->state == DNS_QUERY_PENDING || t->state == DNS_QUERY_NULL)
|
2014-07-16 00:26:02 +02:00
|
|
|
return;
|
|
|
|
|
2014-07-17 19:38:37 +02:00
|
|
|
/* One of the transactions is successful, let's use
|
|
|
|
* it, and copy its data out */
|
2014-07-16 00:26:02 +02:00
|
|
|
if (t->state == DNS_QUERY_SUCCESS) {
|
2014-07-23 01:59:36 +02:00
|
|
|
DnsAnswer *a;
|
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
if (t->received) {
|
2014-07-23 01:59:36 +02:00
|
|
|
rcode = DNS_PACKET_RCODE(t->received);
|
|
|
|
a = t->received->answer;
|
2014-07-22 21:48:41 +02:00
|
|
|
} else {
|
2014-07-23 01:59:36 +02:00
|
|
|
rcode = t->cached_rcode;
|
|
|
|
a = t->cached;
|
2014-07-22 21:48:41 +02:00
|
|
|
}
|
2014-07-17 19:38:37 +02:00
|
|
|
|
2014-07-23 01:59:36 +02:00
|
|
|
if (state == DNS_QUERY_SUCCESS) {
|
|
|
|
DnsAnswer *merged;
|
|
|
|
|
|
|
|
merged = dns_answer_merge(answer, a);
|
|
|
|
if (!merged) {
|
|
|
|
dns_query_complete(q, DNS_QUERY_RESOURCES);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
dns_answer_unref(answer);
|
|
|
|
answer = merged;
|
|
|
|
} else {
|
|
|
|
dns_answer_unref(answer);
|
|
|
|
answer = dns_answer_ref(a);
|
|
|
|
}
|
|
|
|
|
|
|
|
scope = t->scope;
|
|
|
|
state = DNS_QUERY_SUCCESS;
|
|
|
|
continue;
|
2014-07-16 00:26:02 +02:00
|
|
|
}
|
|
|
|
|
2014-07-16 20:15:47 +02:00
|
|
|
/* One of the transactions has failed, let's see
|
|
|
|
* whether we find anything better, but if not, return
|
2014-07-23 01:59:36 +02:00
|
|
|
* its response data */
|
|
|
|
if (state != DNS_QUERY_SUCCESS && t->state == DNS_QUERY_FAILURE) {
|
|
|
|
DnsAnswer *a;
|
|
|
|
|
2014-07-23 00:57:25 +02:00
|
|
|
if (t->received) {
|
2014-07-23 01:59:36 +02:00
|
|
|
rcode = DNS_PACKET_RCODE(t->received);
|
|
|
|
a = t->received->answer;
|
2014-07-23 00:57:25 +02:00
|
|
|
} else {
|
2014-07-23 01:59:36 +02:00
|
|
|
rcode = t->cached_rcode;
|
|
|
|
a = t->cached;
|
2014-07-23 00:57:25 +02:00
|
|
|
}
|
|
|
|
|
2014-07-23 01:59:36 +02:00
|
|
|
dns_answer_unref(answer);
|
|
|
|
answer = dns_answer_ref(a);
|
|
|
|
|
|
|
|
scope = t->scope;
|
2014-07-16 00:26:02 +02:00
|
|
|
state = DNS_QUERY_FAILURE;
|
2014-07-16 20:15:47 +02:00
|
|
|
continue;
|
|
|
|
}
|
2014-07-16 00:26:02 +02:00
|
|
|
|
2014-07-16 20:15:47 +02:00
|
|
|
if (state == DNS_QUERY_NO_SERVERS && t->state != DNS_QUERY_NO_SERVERS)
|
2014-07-16 00:26:02 +02:00
|
|
|
state = t->state;
|
|
|
|
}
|
|
|
|
|
2014-07-23 01:59:36 +02:00
|
|
|
if (IN_SET(state, DNS_QUERY_SUCCESS, DNS_QUERY_FAILURE)) {
|
|
|
|
q->answer = dns_answer_ref(answer);
|
|
|
|
q->answer_rcode = rcode;
|
|
|
|
q->answer_ifindex = (scope && scope->link) ? scope->link->ifindex : 0;
|
2014-07-22 21:48:41 +02:00
|
|
|
}
|
2014-07-16 00:26:02 +02:00
|
|
|
|
2014-07-17 19:38:37 +02:00
|
|
|
dns_query_complete(q, state);
|
2014-07-16 00:26:02 +02:00
|
|
|
}
|
2014-07-16 22:09:00 +02:00
|
|
|
|
2014-07-17 19:38:37 +02:00
|
|
|
int dns_query_cname_redirect(DnsQuery *q, const char *name) {
|
2014-07-22 21:48:41 +02:00
|
|
|
_cleanup_(dns_question_unrefp) DnsQuestion *nq = NULL;
|
|
|
|
int r;
|
2014-07-16 22:09:00 +02:00
|
|
|
|
|
|
|
assert(q);
|
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
if (q->n_cname_redirects > CNAME_MAX)
|
2014-07-16 22:09:00 +02:00
|
|
|
return -ELOOP;
|
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
r = dns_question_cname_redirect(q->question, name, &nq);
|
|
|
|
if (r < 0)
|
|
|
|
return r;
|
2014-07-16 22:09:00 +02:00
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
dns_question_unref(q->question);
|
|
|
|
q->question = nq;
|
|
|
|
nq = NULL;
|
2014-07-16 22:09:00 +02:00
|
|
|
|
2014-07-22 21:48:41 +02:00
|
|
|
q->n_cname_redirects++;
|
2014-07-16 22:09:00 +02:00
|
|
|
|
2014-07-17 19:38:37 +02:00
|
|
|
dns_query_stop(q);
|
|
|
|
q->state = DNS_QUERY_NULL;
|
|
|
|
|
2014-07-16 22:09:00 +02:00
|
|
|
return 0;
|
|
|
|
}
|
2014-07-29 23:52:23 +02:00
|
|
|
|
|
|
|
static const char* const dns_query_state_table[_DNS_QUERY_STATE_MAX] = {
|
|
|
|
[DNS_QUERY_NULL] = "null",
|
|
|
|
[DNS_QUERY_PENDING] = "pending",
|
|
|
|
[DNS_QUERY_FAILURE] = "failure",
|
|
|
|
[DNS_QUERY_SUCCESS] = "success",
|
|
|
|
[DNS_QUERY_NO_SERVERS] = "no-servers",
|
|
|
|
[DNS_QUERY_TIMEOUT] = "timeout",
|
|
|
|
[DNS_QUERY_ATTEMPTS_MAX] = "attempts-max",
|
|
|
|
[DNS_QUERY_INVALID_REPLY] = "invalid-reply",
|
|
|
|
[DNS_QUERY_RESOURCES] = "resources",
|
|
|
|
[DNS_QUERY_ABORTED] = "aborted",
|
|
|
|
};
|
|
|
|
DEFINE_STRING_TABLE_LOOKUP(dns_query_state, DnsQueryState);
|