Add SPDX license identifiers to source files under the LGPL

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

diff --git a/src/resolve/resolved-dns-server.c b/src/resolve/resolved-dns-server.c
index 5498f7b9cbdcd0f985f626a9652a64b16383b857..d470a645245e44f62590a9f118435df88def3dd2 100644 (file)
--- a/src/resolve/resolved-dns-server.c
+++ b/src/resolve/resolved-dns-server.c
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
 /***
   This file is part of systemd.
 
@@ -17,7 +18,7 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
-#include <sd-messages.h>
+#include "sd-messages.h"
 
 #include "alloc-util.h"
 #include "resolved-dns-server.h"
@@ -70,15 +71,12 @@ int dns_server_new(
 
         s->n_ref = 1;
         s->manager = m;
-        s->verified_feature_level = _DNS_SERVER_FEATURE_LEVEL_INVALID;
-        s->possible_feature_level = DNS_SERVER_FEATURE_LEVEL_BEST;
-        s->features_grace_period_usec = DNS_SERVER_FEATURE_GRACE_PERIOD_MIN_USEC;
-        s->received_udp_packet_max = DNS_PACKET_UNICAST_SIZE_MAX;
         s->type = type;
         s->family = family;
         s->address = *in_addr;
         s->ifindex = ifindex;
-        s->resend_timeout = DNS_TIMEOUT_MIN_USEC;
+
+        dns_server_reset_features(s);
 
         switch (type) {
 
@@ -304,7 +302,10 @@ void dns_server_packet_received(DnsServer *s, int protocol, DnsServerFeatureLeve
         if (s->max_rtt < rtt) {
                 s->max_rtt = rtt;
                 s->resend_timeout = CLAMP(s->max_rtt * 2, DNS_TIMEOUT_MIN_USEC, DNS_TIMEOUT_MAX_USEC);
-        }
+        } else if (s->resend_timeout > rtt)
+                /* If we received the packet faster than the resend_timeout, bias
+                 * the resend_timeout back to the rtt. */
+                s->resend_timeout = CLAMP((2 * s->resend_timeout + rtt) / 3, DNS_TIMEOUT_MIN_USEC, DNS_TIMEOUT_MAX_USEC);
 }
 
 void dns_server_packet_lost(DnsServer *s, int protocol, DnsServerFeatureLevel level, usec_t usec) {
@@ -716,9 +717,9 @@ DnsServer *manager_set_dns_server(Manager *m, DnsServer *s) {
                 return s;
 
         if (s)
-                log_info("Switching to %s DNS server %s.",
-                         dns_server_type_to_string(s->type),
-                         dns_server_string(s));
+                log_debug("Switching to %s DNS server %s.",
+                          dns_server_type_to_string(s->type),
+                          dns_server_string(s));
 
         dns_server_unref(m->current_dns_server);
         m->current_dns_server = dns_server_ref(s);
@@ -825,6 +826,85 @@ void dns_server_flush_cache(DnsServer *s) {
         dns_cache_flush(&scope->cache);
 }
 
+void dns_server_reset_features(DnsServer *s) {
+        assert(s);
+
+        s->max_rtt = 0;
+        s->resend_timeout = DNS_TIMEOUT_MIN_USEC;
+
+        s->verified_feature_level = _DNS_SERVER_FEATURE_LEVEL_INVALID;
+        s->possible_feature_level = DNS_SERVER_FEATURE_LEVEL_BEST;
+
+        s->received_udp_packet_max = DNS_PACKET_UNICAST_SIZE_MAX;
+
+        s->packet_bad_opt = false;
+        s->packet_rrsig_missing = false;
+
+        s->features_grace_period_usec = DNS_SERVER_FEATURE_GRACE_PERIOD_MIN_USEC;
+
+        s->warned_downgrade = false;
+
+        dns_server_reset_counters(s);
+}
+
+void dns_server_reset_features_all(DnsServer *s) {
+        DnsServer *i;
+
+        LIST_FOREACH(servers, i, s)
+                dns_server_reset_features(i);
+}
+
+void dns_server_dump(DnsServer *s, FILE *f) {
+        assert(s);
+
+        if (!f)
+                f = stdout;
+
+        fputs("[Server ", f);
+        fputs(dns_server_string(s), f);
+        fputs(" type=", f);
+        fputs(dns_server_type_to_string(s->type), f);
+
+        if (s->type == DNS_SERVER_LINK) {
+                assert(s->link);
+
+                fputs(" interface=", f);
+                fputs(s->link->name, f);
+        }
+
+        fputs("]\n", f);
+
+        fputs("\tVerified feature level: ", f);
+        fputs(strna(dns_server_feature_level_to_string(s->verified_feature_level)), f);
+        fputc('\n', f);
+
+        fputs("\tPossible feature level: ", f);
+        fputs(strna(dns_server_feature_level_to_string(s->possible_feature_level)), f);
+        fputc('\n', f);
+
+        fputs("\tDNSSEC Mode: ", f);
+        fputs(strna(dnssec_mode_to_string(dns_server_get_dnssec_mode(s))), f);
+        fputc('\n', f);
+
+        fputs("\tCan do DNSSEC: ", f);
+        fputs(yes_no(dns_server_dnssec_supported(s)), f);
+        fputc('\n', f);
+
+        fprintf(f,
+                "\tMaximum UDP packet size received: %zu\n"
+                "\tFailed UDP attempts: %u\n"
+                "\tFailed TCP attempts: %u\n"
+                "\tSeen truncated packet: %s\n"
+                "\tSeen OPT RR getting lost: %s\n"
+                "\tSeen RRSIG RR missing: %s\n",
+                s->received_udp_packet_max,
+                s->n_failed_udp,
+                s->n_failed_tcp,
+                yes_no(s->packet_truncated),
+                yes_no(s->packet_bad_opt),
+                yes_no(s->packet_rrsig_missing));
+}
+
 static const char* const dns_server_type_table[_DNS_SERVER_TYPE_MAX] = {
         [DNS_SERVER_SYSTEM] = "system",
         [DNS_SERVER_FALLBACK] = "fallback",