resolved: degrade the feature level on explicit failure

Previously, we would only degrade on packet loss, but when adding EDNS0 support,
we also have to handle the case where the server replies with an explicit error.

1 files changed, 10 insertions, 0 deletions

diff --git a/src/resolve/resolved-dns-server.c b/src/resolve/resolved-dns-server.c
index 5fc7c3187f..c5396a03c8 100644
--- a/src/resolve/resolved-dns-server.c
+++ b/src/resolve/resolved-dns-server.c
@@ -253,6 +253,16 @@ void dns_server_packet_lost(DnsServer *s, DnsServerFeatureLevel features, usec_t
         s->resend_timeout = MIN(s->resend_timeout * 2, DNS_TIMEOUT_MAX_USEC);
 }
 
+void dns_server_packet_failed(DnsServer *s, DnsServerFeatureLevel features) {
+        assert(s);
+        assert(s->manager);
+
+        if (s->possible_features != features)
+                return;
+
+        s->n_failed_attempts  = (unsigned) -1;
+}
+
 static bool dns_server_grace_period_expired(DnsServer *s) {
         usec_t ts;