resolve-host: use the usual log message when encountering a dbus parse failure

[elogind.git] / src / resolve / resolved-dns-query.c

diff --git a/src/resolve/resolved-dns-query.c b/src/resolve/resolved-dns-query.c
index ecffe069592ac1a7c60cd88bc72bd5b49101c6d5..14ae68395f218ad28a264801a4f80ad4241e4e37 100644 (file)
--- a/src/resolve/resolved-dns-query.c
+++ b/src/resolve/resolved-dns-query.c
@@ -19,15 +19,32 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
+#include "af-list.h"
+
 #include "resolved-dns-query.h"
 #include "resolved-dns-domain.h"
 
-#define TRANSACTION_TIMEOUT_USEC (5 * USEC_PER_SEC)
+/* After how much time to repeat classic DNS requests */
+#define DNS_TRANSACTION_TIMEOUT_USEC (5 * USEC_PER_SEC)
+
+/* After how much time to repeat LLMNR requests, see RFC 4795 Section 7 */
+#define LLMNR_TRANSACTION_TIMEOUT_USEC (1 * USEC_PER_SEC)
+
+/* How long to wait for the query in total */
 #define QUERY_TIMEOUT_USEC (30 * USEC_PER_SEC)
-#define ATTEMPTS_MAX 8
+
+/* Maximum attempts to send DNS requests, across all DNS servers */
+#define DNS_TRANSACTION_ATTEMPTS_MAX 8
+
+/* Maximum attempts to send LLMNR requests, see RFC 4795 Section 2.7 */
+#define LLMNR_TRANSACTION_ATTEMPTS_MAX 3
+
 #define CNAME_MAX 8
 #define QUERIES_MAX 2048
 
+#define TRANSACTION_TIMEOUT_USEC(p) ((t)->scope->protocol == DNS_PROTOCOL_LLMNR ? LLMNR_TRANSACTION_TIMEOUT_USEC : DNS_TRANSACTION_TIMEOUT_USEC)
+#define TRANSACTION_ATTEMPTS_MAX(p) ((t)->scope->protocol == DNS_PROTOCOL_LLMNR ? LLMNR_TRANSACTION_ATTEMPTS_MAX : DNS_TRANSACTION_ATTEMPTS_MAX)
+
 static int dns_query_transaction_go(DnsQueryTransaction *t);
 
 DnsQueryTransaction* dns_query_transaction_free(DnsQueryTransaction *t) {
@@ -132,6 +149,12 @@ void dns_query_transaction_complete(DnsQueryTransaction *t, DnsQueryState state)
          * should hence not attempt to access the query or transaction
          * after calling this function. */
 
+        log_debug("Transaction on scope %s on %s/%s now complete with %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),
+                  dns_query_state_to_string(state));
+
         t->state = state;
 
         dns_query_transaction_stop(t);
@@ -261,17 +284,6 @@ void dns_query_transaction_process_reply(DnsQueryTransaction *t, DnsPacket *p) {
                 if (p->family != t->scope->family)
                         return;
 
-                /* Don't accept UDP packets directed to anything but
-                 * the LLMNR multicast addresses. */
-
-                if (p->ipproto == IPPROTO_UDP) {
-                        if (p->family == AF_INET && !in_addr_equal(AF_INET, &p->destination, (union in_addr_union*) &LLMNR_MULTICAST_IPV4_ADDRESS))
-                                return;
-
-                        if (p->family == AF_INET6 && !in_addr_equal(AF_INET6, &p->destination, (union in_addr_union*) &LLMNR_MULTICAST_IPV6_ADDRESS))
-                                return;
-                }
-
                 /* Tentative replies shall be discarded, see RFC 4795,
                  * 2.1.1 */
 
@@ -347,7 +359,8 @@ void dns_query_transaction_process_reply(DnsQueryTransaction *t, DnsPacket *p) {
                 return;
         }
 
-        dns_cache_put(&t->scope->cache, p->question, DNS_PACKET_RCODE(p), p->answer, 0);
+        /* 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);
 
         if (DNS_PACKET_RCODE(p) == DNS_RCODE_SUCCESS)
                 dns_query_transaction_complete(t, DNS_QUERY_SUCCESS);
@@ -413,13 +426,28 @@ static int dns_query_make_packet(DnsQueryTransaction *t) {
 }
 
 static int dns_query_transaction_go(DnsQueryTransaction *t) {
+        bool had_stream;
         int r;
 
         assert(t);
 
+        had_stream = !!t->stream;
+
         dns_query_transaction_stop(t);
 
-        if (t->n_attempts >= ATTEMPTS_MAX) {
+        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));
+
+        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. */
                 dns_query_transaction_complete(t, DNS_QUERY_ATTEMPTS_MAX);
                 return 0;
         }
@@ -479,7 +507,7 @@ static int dns_query_transaction_go(DnsQueryTransaction *t) {
                 return dns_query_transaction_go(t);
         }
 
-        r = sd_event_add_time(t->scope->manager->event, &t->timeout_event_source, CLOCK_MONOTONIC, now(CLOCK_MONOTONIC) + TRANSACTION_TIMEOUT_USEC, 0, on_transaction_timeout, t);
+        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);
         if (r < 0)
                 return r;
 
@@ -889,3 +917,17 @@ int dns_query_cname_redirect(DnsQuery *q, const char *name) {
 
         return 0;
 }
+
+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);