basic/log: add the log_struct terminator to macro

[thirdparty/systemd.git] / src / resolve / resolved-dns-transaction.c

diff --git a/src/resolve/resolved-dns-transaction.c b/src/resolve/resolved-dns-transaction.c
index 792a16d6930d7f3ae03dde741a90aa336aeb6470..acfe987cbed4929c1041fa88fa69db7e39a56823 100644 (file)
--- a/src/resolve/resolved-dns-transaction.c
+++ b/src/resolve/resolved-dns-transaction.c
@@ -3,19 +3,6 @@
   This file is part of systemd.
 
   Copyright 2014 Lennart Poettering
-
-  systemd is free software; you can redistribute it and/or modify it
-  under the terms of the GNU Lesser General Public License as published by
-  the Free Software Foundation; either version 2.1 of the License, or
-  (at your option) any later version.
-
-  systemd is distributed in the hope that it will be useful, but
-  WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-  Lesser General Public License for more details.
-
-  You should have received a copy of the GNU Lesser General Public License
-  along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
 #include "sd-messages.h"
@@ -326,8 +313,7 @@ void dns_transaction_complete(DnsTransaction *t, DnsTransactionState state) {
                            "DNS_QUESTION=%s", key_str,
                            "DNSSEC_RESULT=%s", dnssec_result_to_string(t->answer_dnssec_result),
                            "DNS_SERVER=%s", dns_server_string(t->server),
-                           "DNS_SERVER_FEATURE_LEVEL=%s", dns_server_feature_level_to_string(t->server->possible_feature_level),
-                           NULL);
+                           "DNS_SERVER_FEATURE_LEVEL=%s", dns_server_feature_level_to_string(t->server->possible_feature_level));
         }
 
         /* Note that this call might invalidate the query. Callers
@@ -408,6 +394,8 @@ static int dns_transaction_pick_server(DnsTransaction *t) {
         dns_server_unref(t->server);
         t->server = dns_server_ref(server);
 
+        t->n_picked_servers ++;
+
         log_debug("Using DNS server %s for transaction %u.", dns_server_string(t->server), t->id);
 
         return 1;
@@ -689,7 +677,6 @@ static int dns_transaction_dnssec_ready(DnsTransaction *t) {
                         dns_transaction_complete(t, DNS_TRANSACTION_DNSSEC_FAILED);
                         return 0;
 
-
                 default:
                         log_debug("Auxiliary DNSSEC RR query failed with %s", dns_transaction_state_to_string(dt->state));
                         goto fail;
@@ -737,8 +724,17 @@ static void dns_transaction_process_dnssec(DnsTransaction *t) {
 
         if (t->answer_dnssec_result == DNSSEC_INCOMPATIBLE_SERVER &&
             t->scope->dnssec_mode == DNSSEC_YES) {
-                /*  We are not in automatic downgrade mode, and the
-                 *  server is bad, refuse operation. */
+
+                /*  We are not in automatic downgrade mode, and the server is bad. Let's try a different server, maybe
+                 *  that works. */
+
+                if (t->n_picked_servers < dns_scope_get_n_dns_servers(t->scope)) {
+                        /* We tried fewer servers on this transaction than we know, let's try another one then */
+                        dns_transaction_retry(t, true);
+                        return;
+                }
+
+                /* OK, let's give up, apparently all servers we tried didn't work. */
                 dns_transaction_complete(t, DNS_TRANSACTION_DNSSEC_FAILED);
                 return;
         }
@@ -913,12 +909,21 @@ void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) {
                         /* Request failed, immediately try again with reduced features */
 
                         if (t->current_feature_level <= DNS_SERVER_FEATURE_LEVEL_UDP) {
+
                                 /* This was already at UDP feature level? If so, it doesn't make sense to downgrade
-                                 * this transaction anymore, hence let's process the response, and accept the
+                                 * this transaction anymore, but let's see if it might make sense to send the request
+                                 * to a different DNS server instead. If not let's process the response, and accept the
                                  * rcode. Note that we don't retry on TCP, since that's a suitable way to mitigate
                                  * packet loss, but is not going to give us better rcodes should we actually have
                                  * managed to get them already at UDP level. */
 
+                                if (t->n_picked_servers < dns_scope_get_n_dns_servers(t->scope)) {
+                                        /* We tried fewer servers on this transaction than we know, let's try another one then */
+                                        dns_transaction_retry(t, true);
+                                        return;
+                                }
+
+                                /* Give up, accept the rcode */
                                 log_debug("Server returned error: %s", dns_rcode_to_string(DNS_PACKET_RCODE(p)));
                                 break;
                         }
@@ -1218,7 +1223,6 @@ static usec_t transaction_get_resend_timeout(DnsTransaction *t) {
         assert(t);
         assert(t->scope);
 
-
         switch (t->scope->protocol) {
 
         case DNS_PROTOCOL_DNS:
@@ -1351,7 +1355,7 @@ static int dns_transaction_prepare(DnsTransaction *t, usec_t ts) {
                 /* 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);
+                (void) dns_scope_get_dns_server(t->scope);
 
                 /* Let's then prune all outdated entries */
                 dns_cache_prune(&t->scope->cache);
@@ -1510,8 +1514,7 @@ static int dns_transaction_make_packet_mdns(DnsTransaction *t) {
         }
         DNS_PACKET_HEADER(p)->nscount = htobe16(nscount);
 
-        t->sent = p;
-        p = NULL;
+        t->sent = TAKE_PTR(p);
 
         return 0;
 }
@@ -1539,8 +1542,7 @@ static int dns_transaction_make_packet(DnsTransaction *t) {
         DNS_PACKET_HEADER(p)->qdcount = htobe16(1);
         DNS_PACKET_HEADER(p)->id = t->id;
 
-        t->sent = p;
-        p = NULL;
+        t->sent = TAKE_PTR(p);
 
         return 0;
 }
@@ -3059,8 +3061,7 @@ int dns_transaction_validate_dnssec(DnsTransaction *t) {
         }
 
         dns_answer_unref(t->answer);
-        t->answer = validated;
-        validated = NULL;
+        t->answer = TAKE_PTR(validated);
 
         /* At this point the answer only contains validated
          * RRsets. Now, let's see if it actually answers the question