resolved: respond to local resolver requests on 127.0.0.53:53

[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 5acfcb42392e3e35f7b656647bae5501300c4cc7..7226111c075ea922cb165b524f587868edf8f997 100644 (file)
--- a/src/resolve/resolved-dns-server.c
+++ b/src/resolve/resolved-dns-server.c
@@ -21,6 +21,7 @@
 
 #include "alloc-util.h"
 #include "resolved-dns-server.h"
+#include "resolved-dns-stub.h"
 #include "resolved-resolv-conf.h"
 #include "siphash24.h"
 #include "string-table.h"
@@ -517,7 +518,7 @@ int dns_server_adjust_opt(DnsServer *server, DnsPacket *packet, DnsServerFeature
         else
                 packet_size = server->received_udp_packet_max;
 
-        return dns_packet_append_opt(packet, packet_size, edns_do, NULL);
+        return dns_packet_append_opt(packet, packet_size, edns_do, 0, NULL);
 }
 
 int dns_server_ifindex(const DnsServer *s) {
@@ -750,6 +751,19 @@ void manager_next_dns_server(Manager *m) {
                 manager_set_dns_server(m, m->dns_servers);
 }
 
+bool dns_server_address_valid(int family, const union in_addr_union *sa) {
+
+        /* Refuses the 0 IP addresses as well as 127.0.0.53 (which is our own DNS stub) */
+
+        if (in_addr_is_null(family, sa))
+                return false;
+
+        if (family == AF_INET && sa->in.s_addr == htobe32(INADDR_DNS_STUB))
+                return false;
+
+        return true;
+}
+
 static const char* const dns_server_type_table[_DNS_SERVER_TYPE_MAX] = {
         [DNS_SERVER_SYSTEM] = "system",
         [DNS_SERVER_FALLBACK] = "fallback",