1476 lines
51 KiB
C
1476 lines
51 KiB
C
/*-*- 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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#include "af-list.h"
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#include "alloc-util.h"
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#include "dns-domain.h"
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#include "fd-util.h"
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#include "random-util.h"
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#include "resolved-dns-cache.h"
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#include "resolved-dns-transaction.h"
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#include "resolved-llmnr.h"
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#include "string-table.h"
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DnsTransaction* dns_transaction_free(DnsTransaction *t) {
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DnsQueryCandidate *c;
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DnsZoneItem *i;
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DnsTransaction *z;
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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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dns_packet_unref(t->sent);
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dns_packet_unref(t->received);
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dns_answer_unref(t->answer);
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sd_event_source_unref(t->dns_udp_event_source);
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safe_close(t->dns_udp_fd);
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dns_server_unref(t->server);
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dns_stream_free(t->stream);
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if (t->scope) {
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hashmap_remove_value(t->scope->transactions_by_key, t->key, t);
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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_transactions, UINT_TO_PTR(t->id));
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}
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dns_resource_key_unref(t->key);
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while ((c = set_steal_first(t->notify_query_candidates)))
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set_remove(c->transactions, t);
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set_free(t->notify_query_candidates);
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while ((i = set_steal_first(t->notify_zone_items)))
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i->probe_transaction = NULL;
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set_free(t->notify_zone_items);
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while ((z = set_steal_first(t->notify_transactions)))
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set_remove(z->dnssec_transactions, t);
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set_free(t->notify_transactions);
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while ((z = set_steal_first(t->dnssec_transactions))) {
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set_remove(z->notify_transactions, t);
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dns_transaction_gc(z);
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}
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set_free(t->dnssec_transactions);
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dns_answer_unref(t->validated_keys);
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free(t);
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return NULL;
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}
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DEFINE_TRIVIAL_CLEANUP_FUNC(DnsTransaction*, dns_transaction_free);
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void dns_transaction_gc(DnsTransaction *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->notify_query_candidates) &&
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set_isempty(t->notify_zone_items) &&
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set_isempty(t->notify_transactions))
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dns_transaction_free(t);
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}
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int dns_transaction_new(DnsTransaction **ret, DnsScope *s, DnsResourceKey *key) {
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_cleanup_(dns_transaction_freep) DnsTransaction *t = NULL;
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int r;
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assert(ret);
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assert(s);
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assert(key);
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/* Don't allow looking up invalid or pseudo RRs */
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if (IN_SET(key->type, DNS_TYPE_OPT, 0, DNS_TYPE_TSIG, DNS_TYPE_TKEY))
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return -EINVAL;
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/* We only support the IN class */
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if (key->class != DNS_CLASS_IN)
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return -EOPNOTSUPP;
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r = hashmap_ensure_allocated(&s->manager->dns_transactions, NULL);
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if (r < 0)
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return r;
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r = hashmap_ensure_allocated(&s->transactions_by_key, &dns_resource_key_hash_ops);
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if (r < 0)
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return r;
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t = new0(DnsTransaction, 1);
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if (!t)
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return -ENOMEM;
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t->dns_udp_fd = -1;
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t->answer_source = _DNS_TRANSACTION_SOURCE_INVALID;
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t->dnssec_result = _DNSSEC_RESULT_INVALID;
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t->key = dns_resource_key_ref(key);
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/* Find a fresh, unused transaction id */
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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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hashmap_get(s->manager->dns_transactions, UINT_TO_PTR(t->id)));
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r = hashmap_put(s->manager->dns_transactions, UINT_TO_PTR(t->id), t);
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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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r = hashmap_replace(s->transactions_by_key, t->key, t);
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if (r < 0) {
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hashmap_remove(s->manager->dns_transactions, UINT_TO_PTR(t->id));
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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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static void dns_transaction_stop(DnsTransaction *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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t->stream = dns_stream_free(t->stream);
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/* Note that we do not drop the UDP socket here, as we want to
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* reuse it to repeat the interaction. */
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}
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static void dns_transaction_tentative(DnsTransaction *t, DnsPacket *p) {
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_cleanup_free_ char *pretty = NULL;
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DnsZoneItem *z;
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assert(t);
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assert(p);
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if (manager_our_packet(t->scope->manager, p) != 0)
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return;
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in_addr_to_string(p->family, &p->sender, &pretty);
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log_debug("Transaction on scope %s on %s/%s got tentative packet from %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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pretty);
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/* RFC 4795, Section 4.1 says that the peer with the
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* lexicographically smaller IP address loses */
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if (memcmp(&p->sender, &p->destination, FAMILY_ADDRESS_SIZE(p->family)) >= 0) {
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log_debug("Peer has lexicographically larger IP address and thus lost in the conflict.");
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return;
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}
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log_debug("We have the lexicographically larger IP address and thus lost in the conflict.");
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t->block_gc++;
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while ((z = set_first(t->notify_zone_items))) {
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/* First, make sure the zone item drops the reference
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* to us */
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dns_zone_item_probe_stop(z);
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/* Secondly, report this as conflict, so that we might
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* look for a different hostname */
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dns_zone_item_conflict(z);
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}
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t->block_gc--;
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dns_transaction_gc(t);
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}
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void dns_transaction_complete(DnsTransaction *t, DnsTransactionState state) {
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DnsQueryCandidate *c;
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DnsZoneItem *z;
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DnsTransaction *d;
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Iterator i;
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assert(t);
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assert(!DNS_TRANSACTION_IS_LIVE(state));
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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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log_debug("Transaction on scope %s on %s/%s now complete with <%s> from %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_transaction_state_to_string(state),
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t->answer_source < 0 ? "none" : dns_transaction_source_to_string(t->answer_source));
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t->state = state;
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dns_transaction_stop(t);
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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(c, t->notify_query_candidates, i)
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dns_query_candidate_notify(c);
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SET_FOREACH(z, t->notify_zone_items, i)
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dns_zone_item_notify(z);
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SET_FOREACH(d, t->notify_transactions, i)
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dns_transaction_notify(d, t);
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t->block_gc--;
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dns_transaction_gc(t);
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}
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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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DnsTransaction *t;
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assert(s);
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assert(s->transaction);
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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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t->stream = dns_stream_free(t->stream);
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if (error != 0) {
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dns_transaction_complete(t, DNS_TRANSACTION_RESOURCES);
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return 0;
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}
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if (dns_packet_validate_reply(p) <= 0) {
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log_debug("Invalid TCP reply packet.");
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dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);
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return 0;
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}
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dns_scope_check_conflicts(t->scope, p);
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t->block_gc++;
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dns_transaction_process_reply(t, p);
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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_TRANSACTION_PENDING)
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dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);
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return 0;
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}
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static int dns_transaction_open_tcp(DnsTransaction *t) {
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DnsServer *server = NULL;
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_cleanup_close_ int fd = -1;
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int r;
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assert(t);
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if (t->stream)
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return 0;
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switch (t->scope->protocol) {
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case DNS_PROTOCOL_DNS:
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fd = dns_scope_tcp_socket(t->scope, AF_UNSPEC, NULL, 53, &server);
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break;
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case DNS_PROTOCOL_LLMNR:
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/* When we already received a reply 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, NULL);
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else {
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union in_addr_union address;
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int family = AF_UNSPEC;
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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_name_address(DNS_RESOURCE_KEY_NAME(t->key), &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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if (family != t->scope->family)
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return -ESRCH;
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fd = dns_scope_tcp_socket(t->scope, family, &address, LLMNR_PORT, NULL);
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}
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break;
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default:
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return -EAFNOSUPPORT;
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}
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if (fd < 0)
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return fd;
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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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fd = -1;
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r = dns_stream_write_packet(t->stream, t->sent);
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if (r < 0) {
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t->stream = dns_stream_free(t->stream);
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return r;
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}
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dns_server_unref(t->server);
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t->server = dns_server_ref(server);
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t->received = dns_packet_unref(t->received);
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t->answer = dns_answer_unref(t->answer);
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t->answer_rcode = 0;
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t->stream->complete = on_stream_complete;
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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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return 0;
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}
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static void dns_transaction_next_dns_server(DnsTransaction *t) {
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assert(t);
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t->server = dns_server_unref(t->server);
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t->dns_udp_event_source = sd_event_source_unref(t->dns_udp_event_source);
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t->dns_udp_fd = safe_close(t->dns_udp_fd);
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dns_scope_next_dns_server(t->scope);
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}
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static void dns_transaction_cache_answer(DnsTransaction *t) {
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unsigned n_cache;
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assert(t);
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/* For mDNS we cache whenever we get the packet, rather than
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* in each transaction. */
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if (!IN_SET(t->scope->protocol, DNS_PROTOCOL_DNS, DNS_PROTOCOL_LLMNR))
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return;
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/* We never cache if this packet is from the local host, under
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* the assumption that a locally running DNS server would
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* cache this anyway, and probably knows better when to flush
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* the cache then we could. */
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if (!DNS_PACKET_SHALL_CACHE(t->received))
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return;
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/* According to RFC 4795, section 2.9. only the RRs from the
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* answer section shall be cached. However, if we know the
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* message is authenticated, we might as well cache
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* everything. */
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if (t->answer_authenticated)
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n_cache = dns_answer_size(t->answer);
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else
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n_cache = DNS_PACKET_ANCOUNT(t->received);
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dns_cache_put(&t->scope->cache,
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t->key,
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t->answer_rcode,
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t->answer,
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n_cache,
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t->answer_authenticated,
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0,
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t->received->family,
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&t->received->sender);
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}
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static void dns_transaction_process_dnssec(DnsTransaction *t) {
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int r;
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assert(t);
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/* Are there ongoing DNSSEC transactions? If so, let's wait for them. */
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if (!set_isempty(t->dnssec_transactions))
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return;
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/* All our auxiliary DNSSEC transactions are complete now. Try
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* to validate our RRset now. */
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r = dns_transaction_validate_dnssec(t);
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if (r < 0) {
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dns_transaction_complete(t, DNS_TRANSACTION_RESOURCES);
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return;
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}
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if (!IN_SET(t->dnssec_result, _DNSSEC_RESULT_INVALID, DNSSEC_VALIDATED, DNSSEC_NO_SIGNATURE /* FOR NOW! */)) {
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dns_transaction_complete(t, DNS_TRANSACTION_DNSSEC_FAILED);
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return;
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}
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dns_transaction_cache_answer(t);
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if (t->answer_rcode == DNS_RCODE_SUCCESS)
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dns_transaction_complete(t, DNS_TRANSACTION_SUCCESS);
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else
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dns_transaction_complete(t, DNS_TRANSACTION_FAILURE);
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}
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void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) {
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usec_t ts;
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int r;
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assert(t);
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assert(p);
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assert(t->state == DNS_TRANSACTION_PENDING);
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assert(t->scope);
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assert(t->scope->manager);
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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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log_debug("Processing incoming packet on transaction %" PRIu16".", t->id);
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switch (t->scope->protocol) {
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case 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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/* Tentative packets are not full responses but still
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* useful for identifying uniqueness conflicts during
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* probing. */
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if (DNS_PACKET_LLMNR_T(p)) {
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dns_transaction_tentative(t, p);
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return;
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}
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break;
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case DNS_PROTOCOL_MDNS:
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assert(t->scope->link);
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/* For mDNS we will not accept any packets from other 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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break;
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case DNS_PROTOCOL_DNS:
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break;
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default:
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assert_not_reached("Invalid DNS protocol.");
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}
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if (t->received != p) {
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dns_packet_unref(t->received);
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t->received = dns_packet_ref(p);
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}
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t->answer_source = DNS_TRANSACTION_NETWORK;
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if (p->ipproto == IPPROTO_TCP) {
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if (DNS_PACKET_TC(p)) {
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/* Truncated via TCP? Somebody must be fucking with us */
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dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);
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return;
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}
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if (DNS_PACKET_ID(p) != t->id) {
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/* Not the reply to our query? Somebody must be fucking with us */
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dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);
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return;
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}
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}
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assert_se(sd_event_now(t->scope->manager->event, clock_boottime_or_monotonic(), &ts) >= 0);
|
|
|
|
switch (t->scope->protocol) {
|
|
|
|
case DNS_PROTOCOL_DNS:
|
|
assert(t->server);
|
|
|
|
if (IN_SET(DNS_PACKET_RCODE(p), DNS_RCODE_FORMERR, DNS_RCODE_SERVFAIL, DNS_RCODE_NOTIMP)) {
|
|
|
|
/* Request failed, immediately try again with reduced features */
|
|
log_debug("Server returned error: %s", dns_rcode_to_string(DNS_PACKET_RCODE(p)));
|
|
|
|
dns_server_packet_failed(t->server, t->current_features);
|
|
|
|
r = dns_transaction_go(t);
|
|
if (r < 0) {
|
|
dns_transaction_complete(t, DNS_TRANSACTION_RESOURCES);
|
|
return;
|
|
}
|
|
|
|
return;
|
|
} else
|
|
dns_server_packet_received(t->server, t->current_features, ts - t->start_usec, p->size);
|
|
|
|
break;
|
|
|
|
case DNS_PROTOCOL_LLMNR:
|
|
case DNS_PROTOCOL_MDNS:
|
|
dns_scope_packet_received(t->scope, ts - t->start_usec);
|
|
break;
|
|
|
|
default:
|
|
assert_not_reached("Invalid DNS protocol.");
|
|
}
|
|
|
|
if (DNS_PACKET_TC(p)) {
|
|
|
|
/* Truncated packets for mDNS are not allowed. Give up immediately. */
|
|
if (t->scope->protocol == DNS_PROTOCOL_MDNS) {
|
|
dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);
|
|
return;
|
|
}
|
|
|
|
/* Response was truncated, let's try again with good old TCP */
|
|
r = dns_transaction_open_tcp(t);
|
|
if (r == -ESRCH) {
|
|
/* No servers found? Damn! */
|
|
dns_transaction_complete(t, DNS_TRANSACTION_NO_SERVERS);
|
|
return;
|
|
}
|
|
if (r < 0) {
|
|
/* On LLMNR, if we cannot connect to the host,
|
|
* we immediately give up */
|
|
if (t->scope->protocol == DNS_PROTOCOL_LLMNR) {
|
|
dns_transaction_complete(t, DNS_TRANSACTION_RESOURCES);
|
|
return;
|
|
}
|
|
|
|
/* On DNS, couldn't send? Try immediately again, with a new server */
|
|
dns_transaction_next_dns_server(t);
|
|
|
|
r = dns_transaction_go(t);
|
|
if (r < 0) {
|
|
dns_transaction_complete(t, DNS_TRANSACTION_RESOURCES);
|
|
return;
|
|
}
|
|
|
|
return;
|
|
}
|
|
}
|
|
|
|
/* Parse message, if it isn't parsed yet. */
|
|
r = dns_packet_extract(p);
|
|
if (r < 0) {
|
|
dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);
|
|
return;
|
|
}
|
|
|
|
if (IN_SET(t->scope->protocol, DNS_PROTOCOL_DNS, DNS_PROTOCOL_LLMNR)) {
|
|
|
|
/* Only consider responses with equivalent query section to the request */
|
|
r = dns_packet_is_reply_for(p, t->key);
|
|
if (r < 0) {
|
|
dns_transaction_complete(t, DNS_TRANSACTION_RESOURCES);
|
|
return;
|
|
}
|
|
if (r == 0) {
|
|
dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);
|
|
return;
|
|
}
|
|
|
|
/* Install the answer as answer to the transaction */
|
|
dns_answer_unref(t->answer);
|
|
t->answer = dns_answer_ref(p->answer);
|
|
t->answer_rcode = DNS_PACKET_RCODE(p);
|
|
t->answer_authenticated = t->scope->dnssec_mode == DNSSEC_TRUST && DNS_PACKET_AD(p);
|
|
|
|
r = dns_transaction_request_dnssec_keys(t);
|
|
if (r < 0) {
|
|
dns_transaction_complete(t, DNS_TRANSACTION_RESOURCES);
|
|
return;
|
|
}
|
|
if (r > 0) {
|
|
/* There are DNSSEC transactions pending now. Update the state accordingly. */
|
|
t->state = DNS_TRANSACTION_VALIDATING;
|
|
return;
|
|
}
|
|
}
|
|
|
|
dns_transaction_process_dnssec(t);
|
|
}
|
|
|
|
static int on_dns_packet(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
|
|
_cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
|
|
DnsTransaction *t = userdata;
|
|
int r;
|
|
|
|
assert(t);
|
|
assert(t->scope);
|
|
|
|
r = manager_recv(t->scope->manager, fd, DNS_PROTOCOL_DNS, &p);
|
|
if (r <= 0)
|
|
return r;
|
|
|
|
if (dns_packet_validate_reply(p) > 0 &&
|
|
DNS_PACKET_ID(p) == t->id)
|
|
dns_transaction_process_reply(t, p);
|
|
else
|
|
log_debug("Invalid DNS packet, ignoring.");
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int dns_transaction_emit(DnsTransaction *t) {
|
|
int r;
|
|
|
|
assert(t);
|
|
|
|
if (t->scope->protocol == DNS_PROTOCOL_DNS && !t->server) {
|
|
DnsServer *server = NULL;
|
|
_cleanup_close_ int fd = -1;
|
|
|
|
fd = dns_scope_udp_dns_socket(t->scope, &server);
|
|
if (fd < 0)
|
|
return fd;
|
|
|
|
r = sd_event_add_io(t->scope->manager->event, &t->dns_udp_event_source, fd, EPOLLIN, on_dns_packet, t);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
t->dns_udp_fd = fd;
|
|
fd = -1;
|
|
t->server = dns_server_ref(server);
|
|
}
|
|
|
|
r = dns_scope_emit(t->scope, t->dns_udp_fd, t->server, t->sent);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
if (t->server)
|
|
t->current_features = t->server->possible_features;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int on_transaction_timeout(sd_event_source *s, usec_t usec, void *userdata) {
|
|
DnsTransaction *t = userdata;
|
|
int r;
|
|
|
|
assert(s);
|
|
assert(t);
|
|
|
|
if (!t->initial_jitter_scheduled || t->initial_jitter_elapsed) {
|
|
/* Timeout reached? Increase the timeout for the server used */
|
|
switch (t->scope->protocol) {
|
|
case DNS_PROTOCOL_DNS:
|
|
assert(t->server);
|
|
|
|
dns_server_packet_lost(t->server, t->current_features, usec - t->start_usec);
|
|
|
|
break;
|
|
case DNS_PROTOCOL_LLMNR:
|
|
case DNS_PROTOCOL_MDNS:
|
|
dns_scope_packet_lost(t->scope, usec - t->start_usec);
|
|
|
|
break;
|
|
default:
|
|
assert_not_reached("Invalid DNS protocol.");
|
|
}
|
|
|
|
if (t->initial_jitter_scheduled)
|
|
t->initial_jitter_elapsed = true;
|
|
}
|
|
|
|
/* ...and try again with a new server */
|
|
dns_transaction_next_dns_server(t);
|
|
|
|
r = dns_transaction_go(t);
|
|
if (r < 0)
|
|
dns_transaction_complete(t, DNS_TRANSACTION_RESOURCES);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static usec_t transaction_get_resend_timeout(DnsTransaction *t) {
|
|
assert(t);
|
|
assert(t->scope);
|
|
|
|
switch (t->scope->protocol) {
|
|
case DNS_PROTOCOL_DNS:
|
|
assert(t->server);
|
|
|
|
return t->server->resend_timeout;
|
|
case DNS_PROTOCOL_MDNS:
|
|
assert(t->n_attempts > 0);
|
|
return (1 << (t->n_attempts - 1)) * USEC_PER_SEC;
|
|
case DNS_PROTOCOL_LLMNR:
|
|
return t->scope->resend_timeout;
|
|
default:
|
|
assert_not_reached("Invalid DNS protocol.");
|
|
}
|
|
}
|
|
|
|
static int dns_transaction_prepare_next_attempt(DnsTransaction *t, usec_t ts) {
|
|
bool had_stream;
|
|
int r;
|
|
|
|
assert(t);
|
|
|
|
had_stream = !!t->stream;
|
|
|
|
dns_transaction_stop(t);
|
|
|
|
if (t->n_attempts >= TRANSACTION_ATTEMPTS_MAX(t->scope->protocol)) {
|
|
dns_transaction_complete(t, DNS_TRANSACTION_ATTEMPTS_MAX_REACHED);
|
|
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. */
|
|
dns_transaction_complete(t, DNS_TRANSACTION_ATTEMPTS_MAX_REACHED);
|
|
return 0;
|
|
}
|
|
|
|
t->n_attempts++;
|
|
t->start_usec = ts;
|
|
t->received = dns_packet_unref(t->received);
|
|
t->answer = dns_answer_unref(t->answer);
|
|
t->answer_rcode = 0;
|
|
t->answer_source = _DNS_TRANSACTION_SOURCE_INVALID;
|
|
|
|
/* Check the trust anchor. Do so only on classic DNS, since DNSSEC does not apply otherwise. */
|
|
if (t->scope->protocol == DNS_PROTOCOL_DNS) {
|
|
r = dns_trust_anchor_lookup(&t->scope->manager->trust_anchor, t->key, &t->answer);
|
|
if (r < 0)
|
|
return r;
|
|
if (r > 0) {
|
|
t->answer_rcode = DNS_RCODE_SUCCESS;
|
|
t->answer_source = DNS_TRANSACTION_TRUST_ANCHOR;
|
|
t->answer_authenticated = true;
|
|
dns_transaction_complete(t, DNS_TRANSACTION_SUCCESS);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/* Check the zone, but only if this transaction is not used
|
|
* for probing or verifying a zone item. */
|
|
if (set_isempty(t->notify_zone_items)) {
|
|
|
|
r = dns_zone_lookup(&t->scope->zone, t->key, &t->answer, NULL, NULL);
|
|
if (r < 0)
|
|
return r;
|
|
if (r > 0) {
|
|
t->answer_rcode = DNS_RCODE_SUCCESS;
|
|
t->answer_source = DNS_TRANSACTION_ZONE;
|
|
t->answer_authenticated = true;
|
|
dns_transaction_complete(t, DNS_TRANSACTION_SUCCESS);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/* Check the cache, but only if this transaction is not used
|
|
* for probing or verifying a zone item. */
|
|
if (set_isempty(t->notify_zone_items)) {
|
|
|
|
/* Before trying the cache, let's make sure we figured out a
|
|
* server to use. Should this cause a change of server this
|
|
* might flush the cache. */
|
|
dns_scope_get_dns_server(t->scope);
|
|
|
|
/* Let's then prune all outdated entries */
|
|
dns_cache_prune(&t->scope->cache);
|
|
|
|
r = dns_cache_lookup(&t->scope->cache, t->key, &t->answer_rcode, &t->answer, &t->answer_authenticated);
|
|
if (r < 0)
|
|
return r;
|
|
if (r > 0) {
|
|
t->answer_source = DNS_TRANSACTION_CACHE;
|
|
if (t->answer_rcode == DNS_RCODE_SUCCESS)
|
|
dns_transaction_complete(t, DNS_TRANSACTION_SUCCESS);
|
|
else
|
|
dns_transaction_complete(t, DNS_TRANSACTION_FAILURE);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int dns_transaction_make_packet_mdns(DnsTransaction *t) {
|
|
|
|
_cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
|
|
bool add_known_answers = false;
|
|
DnsTransaction *other;
|
|
unsigned qdcount;
|
|
usec_t ts;
|
|
int r;
|
|
|
|
assert(t);
|
|
assert(t->scope->protocol == DNS_PROTOCOL_MDNS);
|
|
|
|
/* Discard any previously prepared packet, so we can start over and coaleasce again */
|
|
t->sent = dns_packet_unref(t->sent);
|
|
|
|
r = dns_packet_new_query(&p, t->scope->protocol, 0, false);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
r = dns_packet_append_key(p, t->key, NULL);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
qdcount = 1;
|
|
|
|
if (dns_key_is_shared(t->key))
|
|
add_known_answers = true;
|
|
|
|
/*
|
|
* For mDNS, we want to coalesce as many open queries in pending transactions into one single
|
|
* query packet on the wire as possible. To achieve that, we iterate through all pending transactions
|
|
* in our current scope, and see whether their timing contraints allow them to be sent.
|
|
*/
|
|
|
|
assert_se(sd_event_now(t->scope->manager->event, clock_boottime_or_monotonic(), &ts) >= 0);
|
|
|
|
LIST_FOREACH(transactions_by_scope, other, t->scope->transactions) {
|
|
|
|
/* Skip ourselves */
|
|
if (other == t)
|
|
continue;
|
|
|
|
if (other->state != DNS_TRANSACTION_PENDING)
|
|
continue;
|
|
|
|
if (other->next_attempt_after > ts)
|
|
continue;
|
|
|
|
if (qdcount >= UINT16_MAX)
|
|
break;
|
|
|
|
r = dns_packet_append_key(p, other->key, NULL);
|
|
|
|
/*
|
|
* If we can't stuff more questions into the packet, just give up.
|
|
* One of the 'other' transactions will fire later and take care of the rest.
|
|
*/
|
|
if (r == -EMSGSIZE)
|
|
break;
|
|
|
|
if (r < 0)
|
|
return r;
|
|
|
|
r = dns_transaction_prepare_next_attempt(other, ts);
|
|
if (r <= 0)
|
|
continue;
|
|
|
|
ts += transaction_get_resend_timeout(other);
|
|
|
|
r = sd_event_add_time(
|
|
other->scope->manager->event,
|
|
&other->timeout_event_source,
|
|
clock_boottime_or_monotonic(),
|
|
ts, 0,
|
|
on_transaction_timeout, other);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
other->state = DNS_TRANSACTION_PENDING;
|
|
other->next_attempt_after = ts;
|
|
|
|
qdcount ++;
|
|
|
|
if (dns_key_is_shared(other->key))
|
|
add_known_answers = true;
|
|
}
|
|
|
|
DNS_PACKET_HEADER(p)->qdcount = htobe16(qdcount);
|
|
DNS_PACKET_HEADER(p)->id = t->id;
|
|
|
|
/* Append known answer section if we're asking for any shared record */
|
|
if (add_known_answers) {
|
|
r = dns_cache_export_shared_to_packet(&t->scope->cache, p);
|
|
if (r < 0)
|
|
return r;
|
|
}
|
|
|
|
t->sent = p;
|
|
p = NULL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int dns_transaction_make_packet(DnsTransaction *t) {
|
|
_cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
|
|
int r;
|
|
|
|
assert(t);
|
|
|
|
if (t->scope->protocol == DNS_PROTOCOL_MDNS)
|
|
return dns_transaction_make_packet_mdns(t);
|
|
|
|
if (t->sent)
|
|
return 0;
|
|
|
|
r = dns_packet_new_query(&p, t->scope->protocol, 0, t->scope->dnssec_mode == DNSSEC_YES);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
r = dns_scope_good_key(t->scope, t->key);
|
|
if (r < 0)
|
|
return r;
|
|
if (r == 0)
|
|
return -EDOM;
|
|
|
|
r = dns_packet_append_key(p, t->key, NULL);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
DNS_PACKET_HEADER(p)->qdcount = htobe16(1);
|
|
DNS_PACKET_HEADER(p)->id = t->id;
|
|
|
|
t->sent = p;
|
|
p = NULL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int dns_transaction_go(DnsTransaction *t) {
|
|
usec_t ts;
|
|
int r;
|
|
|
|
assert(t);
|
|
|
|
assert_se(sd_event_now(t->scope->manager->event, clock_boottime_or_monotonic(), &ts) >= 0);
|
|
|
|
r = dns_transaction_prepare_next_attempt(t, ts);
|
|
if (r <= 0)
|
|
return r;
|
|
|
|
if (log_get_max_level() >= LOG_DEBUG) {
|
|
_cleanup_free_ char *ks = NULL;
|
|
|
|
(void) dns_resource_key_to_string(t->key, &ks);
|
|
|
|
log_debug("Excercising transaction for <%s> on scope %s on %s/%s",
|
|
ks ? strstrip(ks) : "???",
|
|
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));
|
|
}
|
|
|
|
if (!t->initial_jitter_scheduled &&
|
|
(t->scope->protocol == DNS_PROTOCOL_LLMNR ||
|
|
t->scope->protocol == DNS_PROTOCOL_MDNS)) {
|
|
usec_t jitter, accuracy;
|
|
|
|
/* RFC 4795 Section 2.7 suggests all queries should be
|
|
* delayed by a random time from 0 to JITTER_INTERVAL. */
|
|
|
|
t->initial_jitter_scheduled = true;
|
|
|
|
random_bytes(&jitter, sizeof(jitter));
|
|
|
|
switch (t->scope->protocol) {
|
|
case DNS_PROTOCOL_LLMNR:
|
|
jitter %= LLMNR_JITTER_INTERVAL_USEC;
|
|
accuracy = LLMNR_JITTER_INTERVAL_USEC;
|
|
break;
|
|
case DNS_PROTOCOL_MDNS:
|
|
jitter %= MDNS_JITTER_RANGE_USEC;
|
|
jitter += MDNS_JITTER_MIN_USEC;
|
|
accuracy = MDNS_JITTER_RANGE_USEC;
|
|
break;
|
|
default:
|
|
assert_not_reached("bad protocol");
|
|
}
|
|
|
|
r = sd_event_add_time(
|
|
t->scope->manager->event,
|
|
&t->timeout_event_source,
|
|
clock_boottime_or_monotonic(),
|
|
ts + jitter, accuracy,
|
|
on_transaction_timeout, t);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
t->n_attempts = 0;
|
|
t->next_attempt_after = ts;
|
|
t->state = DNS_TRANSACTION_PENDING;
|
|
|
|
log_debug("Delaying %s transaction for " USEC_FMT "us.", dns_protocol_to_string(t->scope->protocol), jitter);
|
|
return 0;
|
|
}
|
|
|
|
/* Otherwise, we need to ask the network */
|
|
r = dns_transaction_make_packet(t);
|
|
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_transaction_complete(t, DNS_TRANSACTION_NO_SERVERS);
|
|
return 0;
|
|
}
|
|
if (r < 0)
|
|
return r;
|
|
|
|
if (t->scope->protocol == DNS_PROTOCOL_LLMNR &&
|
|
(dns_name_endswith(DNS_RESOURCE_KEY_NAME(t->key), "in-addr.arpa") > 0 ||
|
|
dns_name_endswith(DNS_RESOURCE_KEY_NAME(t->key), "ip6.arpa") > 0)) {
|
|
|
|
/* RFC 4795, Section 2.4. says reverse lookups shall
|
|
* always be made via TCP on LLMNR */
|
|
r = dns_transaction_open_tcp(t);
|
|
} else {
|
|
/* Try via UDP, and if that fails due to large size or lack of
|
|
* support try via TCP */
|
|
r = dns_transaction_emit(t);
|
|
if (r == -EMSGSIZE || r == -EAGAIN)
|
|
r = dns_transaction_open_tcp(t);
|
|
}
|
|
|
|
if (r == -ESRCH) {
|
|
/* No servers to send this to? */
|
|
dns_transaction_complete(t, DNS_TRANSACTION_NO_SERVERS);
|
|
return 0;
|
|
} else if (r < 0) {
|
|
if (t->scope->protocol != DNS_PROTOCOL_DNS) {
|
|
dns_transaction_complete(t, DNS_TRANSACTION_RESOURCES);
|
|
return 0;
|
|
}
|
|
|
|
/* Couldn't send? Try immediately again, with a new server */
|
|
dns_transaction_next_dns_server(t);
|
|
|
|
return dns_transaction_go(t);
|
|
}
|
|
|
|
ts += transaction_get_resend_timeout(t);
|
|
|
|
r = sd_event_add_time(
|
|
t->scope->manager->event,
|
|
&t->timeout_event_source,
|
|
clock_boottime_or_monotonic(),
|
|
ts, 0,
|
|
on_transaction_timeout, t);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
t->state = DNS_TRANSACTION_PENDING;
|
|
t->next_attempt_after = ts;
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int dns_transaction_add_dnssec_transaction(DnsTransaction *t, DnsResourceKey *key, DnsTransaction **ret) {
|
|
DnsTransaction *aux;
|
|
int r;
|
|
|
|
assert(t);
|
|
assert(ret);
|
|
assert(key);
|
|
|
|
aux = dns_scope_find_transaction(t->scope, key, true);
|
|
if (!aux) {
|
|
r = dns_transaction_new(&aux, t->scope, key);
|
|
if (r < 0)
|
|
return r;
|
|
} else {
|
|
if (set_contains(t->dnssec_transactions, aux)) {
|
|
*ret = aux;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
r = set_ensure_allocated(&t->dnssec_transactions, NULL);
|
|
if (r < 0)
|
|
goto gc;
|
|
|
|
r = set_ensure_allocated(&aux->notify_transactions, NULL);
|
|
if (r < 0)
|
|
goto gc;
|
|
|
|
r = set_put(t->dnssec_transactions, aux);
|
|
if (r < 0)
|
|
goto gc;
|
|
|
|
r = set_put(aux->notify_transactions, t);
|
|
if (r < 0) {
|
|
(void) set_remove(t->dnssec_transactions, aux);
|
|
goto gc;
|
|
}
|
|
|
|
*ret = aux;
|
|
return 1;
|
|
|
|
gc:
|
|
dns_transaction_gc(aux);
|
|
return r;
|
|
}
|
|
|
|
static int dns_transaction_request_dnssec_rr(DnsTransaction *t, DnsResourceKey *key) {
|
|
_cleanup_(dns_answer_unrefp) DnsAnswer *a = NULL;
|
|
DnsTransaction *aux;
|
|
int r;
|
|
|
|
assert(t);
|
|
assert(key);
|
|
|
|
/* Try to get the data from the trust anchor */
|
|
r = dns_trust_anchor_lookup(&t->scope->manager->trust_anchor, key, &a);
|
|
if (r < 0)
|
|
return r;
|
|
if (r > 0) {
|
|
r = dns_answer_extend(&t->validated_keys, a);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* This didn't work, ask for it via the network/cache then. */
|
|
r = dns_transaction_add_dnssec_transaction(t, key, &aux);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
if (aux->state == DNS_TRANSACTION_NULL) {
|
|
r = dns_transaction_go(aux);
|
|
if (r < 0)
|
|
return r;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int dns_transaction_request_dnssec_keys(DnsTransaction *t) {
|
|
DnsResourceRecord *rr;
|
|
int r;
|
|
|
|
assert(t);
|
|
|
|
if (t->scope->dnssec_mode != DNSSEC_YES)
|
|
return 0;
|
|
|
|
DNS_ANSWER_FOREACH(rr, t->answer) {
|
|
|
|
switch (rr->key->type) {
|
|
|
|
case DNS_TYPE_RRSIG: {
|
|
/* For each RRSIG we request the matching DNSKEY */
|
|
_cleanup_(dns_resource_key_unrefp) DnsResourceKey *dnskey = NULL;
|
|
|
|
/* If this RRSIG is about a DNSKEY RR and the
|
|
* signer is the same as the owner, then we
|
|
* already have the DNSKEY, and we don't have
|
|
* to look for more. */
|
|
if (rr->rrsig.type_covered == DNS_TYPE_DNSKEY) {
|
|
r = dns_name_equal(rr->rrsig.signer, DNS_RESOURCE_KEY_NAME(rr->key));
|
|
if (r < 0)
|
|
return r;
|
|
if (r > 0)
|
|
continue;
|
|
}
|
|
|
|
/* If the signer is not a parent of the owner,
|
|
* then the signature is bogus, let's ignore
|
|
* it. */
|
|
r = dns_name_endswith(DNS_RESOURCE_KEY_NAME(rr->key), rr->rrsig.signer);
|
|
if (r < 0)
|
|
return r;
|
|
if (r == 0)
|
|
continue;
|
|
|
|
dnskey = dns_resource_key_new(rr->key->class, DNS_TYPE_DNSKEY, rr->rrsig.signer);
|
|
if (!dnskey)
|
|
return -ENOMEM;
|
|
|
|
log_debug("Requesting DNSKEY to validate transaction %" PRIu16" (key tag: %" PRIu16 ").", t->id, rr->rrsig.key_tag);
|
|
|
|
r = dns_transaction_request_dnssec_rr(t, dnskey);
|
|
if (r < 0)
|
|
return r;
|
|
break;
|
|
}
|
|
|
|
case DNS_TYPE_DNSKEY: {
|
|
/* For each DNSKEY we request the matching DS */
|
|
_cleanup_(dns_resource_key_unrefp) DnsResourceKey *ds = NULL;
|
|
|
|
ds = dns_resource_key_new(rr->key->class, DNS_TYPE_DS, DNS_RESOURCE_KEY_NAME(rr->key));
|
|
if (!ds)
|
|
return -ENOMEM;
|
|
|
|
log_debug("Requesting DS to validate transaction %" PRIu16" (key tag: %" PRIu16 ").", t->id, dnssec_keytag(rr));
|
|
|
|
r = dns_transaction_request_dnssec_rr(t, ds);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
break;
|
|
}}
|
|
}
|
|
|
|
return !set_isempty(t->dnssec_transactions);
|
|
}
|
|
|
|
void dns_transaction_notify(DnsTransaction *t, DnsTransaction *source) {
|
|
int r;
|
|
|
|
assert(t);
|
|
assert(IN_SET(t->state, DNS_TRANSACTION_PENDING, DNS_TRANSACTION_VALIDATING));
|
|
assert(source);
|
|
|
|
/* Invoked whenever any of our auxiliary DNSSEC transactions
|
|
completed its work. We simply copy the answer from that
|
|
transaction over. */
|
|
|
|
if (source->state != DNS_TRANSACTION_SUCCESS) {
|
|
log_debug("Auxiliary DNSSEC RR query failed.");
|
|
t->dnssec_result = DNSSEC_FAILED_AUXILIARY;
|
|
} else {
|
|
r = dns_answer_extend(&t->validated_keys, source->answer);
|
|
if (r < 0) {
|
|
log_error_errno(r, "Failed to merge validated DNSSEC key data: %m");
|
|
t->dnssec_result = DNSSEC_FAILED_AUXILIARY;
|
|
}
|
|
}
|
|
|
|
/* Detach us from the DNSSEC transaction. */
|
|
(void) set_remove(t->dnssec_transactions, source);
|
|
(void) set_remove(source->notify_transactions, t);
|
|
|
|
/* If the state is still PENDING, we are still in the loop
|
|
* that adds further DNSSEC transactions, hence don't check if
|
|
* we are ready yet. If the state is VALIDATING however, we
|
|
* should check if we are complete now. */
|
|
if (t->state == DNS_TRANSACTION_VALIDATING)
|
|
dns_transaction_process_dnssec(t);
|
|
}
|
|
|
|
int dns_transaction_validate_dnssec(DnsTransaction *t) {
|
|
_cleanup_(dns_answer_unrefp) DnsAnswer *validated = NULL;
|
|
DnsResourceRecord *rr;
|
|
int ifindex, r;
|
|
|
|
assert(t);
|
|
|
|
/* We have now collected all DS and DNSKEY RRs in
|
|
* t->validated_keys, let's see which RRs we can now
|
|
* authenticate with that. */
|
|
|
|
if (t->scope->dnssec_mode != DNSSEC_YES)
|
|
return 0;
|
|
|
|
/* Already validated */
|
|
if (t->dnssec_result != _DNSSEC_RESULT_INVALID)
|
|
return 0;
|
|
|
|
if (IN_SET(t->answer_source, DNS_TRANSACTION_ZONE, DNS_TRANSACTION_TRUST_ANCHOR)) {
|
|
t->dnssec_result = DNSSEC_VALIDATED;
|
|
t->answer_authenticated = true;
|
|
return 0;
|
|
}
|
|
|
|
if (log_get_max_level() >= LOG_DEBUG) {
|
|
_cleanup_free_ char *ks = NULL;
|
|
|
|
(void) dns_resource_key_to_string(t->key, &ks);
|
|
log_debug("Validating response from transaction %" PRIu16 " (%s).", t->id, ks ? strstrip(ks) : "???");
|
|
}
|
|
|
|
/* First see if there are DNSKEYs we already known a validated DS for. */
|
|
DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, t->answer) {
|
|
|
|
r = dnssec_verify_dnskey_search(rr, t->validated_keys);
|
|
if (r < 0)
|
|
return r;
|
|
if (r == 0)
|
|
continue;
|
|
|
|
/* If so, the DNSKEY is validated too. */
|
|
r = dns_answer_add_extend(&t->validated_keys, rr, ifindex);
|
|
if (r < 0)
|
|
return r;
|
|
}
|
|
|
|
for (;;) {
|
|
bool changed = false, missing_key_for_transaction = false;
|
|
|
|
DNS_ANSWER_FOREACH(rr, t->answer) {
|
|
DnssecResult result;
|
|
|
|
if (rr->key->type == DNS_TYPE_RRSIG)
|
|
continue;
|
|
|
|
r = dnssec_verify_rrset_search(t->answer, rr->key, t->validated_keys, USEC_INFINITY, &result);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
if (log_get_max_level() >= LOG_DEBUG) {
|
|
_cleanup_free_ char *rrs = NULL;
|
|
|
|
(void) dns_resource_record_to_string(rr, &rrs);
|
|
log_debug("Looking at %s: %s", rrs ? strstrip(rrs) : "???", dnssec_result_to_string(result));
|
|
}
|
|
|
|
switch (result) {
|
|
|
|
case DNSSEC_VALIDATED:
|
|
|
|
/* Add the validated RRset to the new list of validated RRsets */
|
|
r = dns_answer_copy_by_key(&validated, t->answer, rr->key);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
if (rr->key->type == DNS_TYPE_DNSKEY) {
|
|
/* If we just validated a
|
|
* DNSKEY RRset, then let's
|
|
* add these keys to the set
|
|
* of validated keys for this
|
|
* transaction. */
|
|
|
|
r = dns_answer_copy_by_key(&t->validated_keys, t->answer, rr->key);
|
|
if (r < 0)
|
|
return r;
|
|
}
|
|
|
|
/* Now, remove this RRset from the RRs still to process */
|
|
r = dns_answer_remove_by_key(&t->answer, rr->key);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
changed = true;
|
|
break;
|
|
|
|
case DNSSEC_INVALID:
|
|
case DNSSEC_NO_SIGNATURE:
|
|
case DNSSEC_SIGNATURE_EXPIRED:
|
|
|
|
/* Is this the RRset that we were looking for? If so, this is fatal for the whole transaction */
|
|
r = dns_resource_key_match_rr(t->key, rr, NULL);
|
|
if (r < 0)
|
|
return r;
|
|
if (r > 0) {
|
|
t->dnssec_result = result;
|
|
return 0;
|
|
}
|
|
|
|
/* Is this a CNAME for a record we were looking for? If so, it's also fatal for the whole transaction */
|
|
r = dns_resource_key_match_cname(t->key, rr, NULL);
|
|
if (r < 0)
|
|
return r;
|
|
if (r > 0) {
|
|
t->dnssec_result = result;
|
|
return 0;
|
|
}
|
|
|
|
/* This is just something auxiliary. Just remove the RRset and continue. */
|
|
r = dns_answer_remove_by_key(&t->answer, rr->key);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
changed = true;
|
|
break;
|
|
|
|
case DNSSEC_MISSING_KEY:
|
|
/* They key is missing? Let's continue
|
|
* with the next iteration, maybe
|
|
* we'll find it in an DNSKEY RRset
|
|
* later on. */
|
|
|
|
r = dns_resource_key_equal(rr->key, t->key);
|
|
if (r < 0)
|
|
return r;
|
|
if (r > 0)
|
|
missing_key_for_transaction = true;
|
|
|
|
break;
|
|
|
|
default:
|
|
assert_not_reached("Unexpected DNSSEC result");
|
|
}
|
|
|
|
if (changed)
|
|
break;
|
|
}
|
|
|
|
if (changed)
|
|
continue;
|
|
|
|
/* This didn't work either, there's no point in
|
|
* continuing. */
|
|
if (missing_key_for_transaction) {
|
|
t->dnssec_result = DNSSEC_MISSING_KEY;
|
|
return 0;
|
|
}
|
|
|
|
break;
|
|
}
|
|
|
|
dns_answer_unref(t->answer);
|
|
t->answer = validated;
|
|
validated = NULL;
|
|
|
|
t->answer_authenticated = true;
|
|
t->dnssec_result = DNSSEC_VALIDATED;
|
|
return 1;
|
|
}
|
|
|
|
static const char* const dns_transaction_state_table[_DNS_TRANSACTION_STATE_MAX] = {
|
|
[DNS_TRANSACTION_NULL] = "null",
|
|
[DNS_TRANSACTION_PENDING] = "pending",
|
|
[DNS_TRANSACTION_VALIDATING] = "validating",
|
|
[DNS_TRANSACTION_FAILURE] = "failure",
|
|
[DNS_TRANSACTION_SUCCESS] = "success",
|
|
[DNS_TRANSACTION_NO_SERVERS] = "no-servers",
|
|
[DNS_TRANSACTION_TIMEOUT] = "timeout",
|
|
[DNS_TRANSACTION_ATTEMPTS_MAX_REACHED] = "attempts-max-reached",
|
|
[DNS_TRANSACTION_INVALID_REPLY] = "invalid-reply",
|
|
[DNS_TRANSACTION_RESOURCES] = "resources",
|
|
[DNS_TRANSACTION_ABORTED] = "aborted",
|
|
[DNS_TRANSACTION_DNSSEC_FAILED] = "dnssec-failed",
|
|
};
|
|
DEFINE_STRING_TABLE_LOOKUP(dns_transaction_state, DnsTransactionState);
|
|
|
|
static const char* const dns_transaction_source_table[_DNS_TRANSACTION_SOURCE_MAX] = {
|
|
[DNS_TRANSACTION_NETWORK] = "network",
|
|
[DNS_TRANSACTION_CACHE] = "cache",
|
|
[DNS_TRANSACTION_ZONE] = "zone",
|
|
[DNS_TRANSACTION_TRUST_ANCHOR] = "trust-anchor",
|
|
};
|
|
DEFINE_STRING_TABLE_LOOKUP(dns_transaction_source, DnsTransactionSource);
|