+ if (s->protocol == DNS_PROTOCOL_LLMNR) {
+ if (dns_name_endswith(domain, "in-addr.arpa") > 0 ||
+ dns_name_endswith(domain, "ip6.arpa") > 0 ||
+ dns_name_single_label(domain) > 0)
+ return DNS_SCOPE_MAYBE;
+
+ return DNS_SCOPE_NO;
+ }
+
+ assert_not_reached("Unknown scope protocol");
+}
+
+int dns_scope_good_key(DnsScope *s, DnsResourceKey *key) {
+ assert(s);
+ assert(key);
+
+ if (s->protocol == DNS_PROTOCOL_DNS)
+ return true;
+
+ /* On mDNS and LLMNR, send A and AAAA queries only on the
+ * respective scopes */
+
+ if (s->family == AF_INET && key->class == DNS_CLASS_IN && key->type == DNS_TYPE_AAAA)
+ return false;
+
+ if (s->family == AF_INET6 && key->class == DNS_CLASS_IN && key->type == DNS_TYPE_A)
+ return false;
+
+ return true;
+}
+
+int dns_scope_llmnr_membership(DnsScope *s, bool b) {
+ int fd;
+
+ if (s->family == AF_INET) {
+ struct ip_mreqn mreqn = {
+ .imr_multiaddr = LLMNR_MULTICAST_IPV4_ADDRESS,
+ .imr_ifindex = s->link->ifindex,
+ };
+
+ fd = manager_llmnr_ipv4_udp_fd(s->manager);
+ if (fd < 0)
+ return fd;
+
+ /* Always first try to drop membership before we add
+ * one. This is necessary on some devices, such as
+ * veth. */
+ if (b)
+ setsockopt(fd, IPPROTO_IP, IP_DROP_MEMBERSHIP, &mreqn, sizeof(mreqn));
+
+ if (setsockopt(fd, IPPROTO_IP, b ? IP_ADD_MEMBERSHIP : IP_DROP_MEMBERSHIP, &mreqn, sizeof(mreqn)) < 0)
+ return -errno;
+
+ } else if (s->family == AF_INET6) {
+ struct ipv6_mreq mreq = {
+ .ipv6mr_multiaddr = LLMNR_MULTICAST_IPV6_ADDRESS,
+ .ipv6mr_interface = s->link->ifindex,
+ };
+
+ fd = manager_llmnr_ipv6_udp_fd(s->manager);
+ if (fd < 0)
+ return fd;
+
+ if (b)
+ setsockopt(fd, IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP, &mreq, sizeof(mreq));
+
+ if (setsockopt(fd, IPPROTO_IPV6, b ? IPV6_ADD_MEMBERSHIP : IPV6_DROP_MEMBERSHIP, &mreq, sizeof(mreq)) < 0)
+ return -errno;
+ } else
+ return -EAFNOSUPPORT;
+
+ return 0;
+}
+
+int dns_scope_good_dns_server(DnsScope *s, int family, const union in_addr_union *address) {
+ assert(s);
+ assert(address);
+
+ if (s->protocol != DNS_PROTOCOL_DNS)
+ return 1;
+
+ if (s->link)
+ return !!link_find_dns_server(s->link, family, address);
+ else
+ return !!manager_find_dns_server(s->manager, family, address);
+}
+
+static int dns_scope_make_reply_packet(
+ DnsScope *s,
+ uint16_t id,
+ int rcode,
+ DnsQuestion *q,
+ DnsAnswer *answer,
+ DnsAnswer *soa,
+ bool tentative,
+ DnsPacket **ret) {
+
+ _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
+ unsigned i;
+ int r;
+
+ assert(s);
+
+ if ((!q || q->n_keys <= 0)
+ && (!answer || answer->n_rrs <= 0)
+ && (!soa || soa->n_rrs <= 0))
+ return -EINVAL;
+
+ r = dns_packet_new(&p, s->protocol, 0);
+ if (r < 0)
+ return r;
+
+ DNS_PACKET_HEADER(p)->id = id;
+ DNS_PACKET_HEADER(p)->flags = htobe16(DNS_PACKET_MAKE_FLAGS(
+ 1 /* qr */,
+ 0 /* opcode */,
+ 0 /* c */,
+ 0 /* tc */,
+ tentative,
+ 0 /* (ra) */,
+ 0 /* (ad) */,
+ 0 /* (cd) */,
+ rcode));
+
+ if (q) {
+ for (i = 0; i < q->n_keys; i++) {
+ r = dns_packet_append_key(p, q->keys[i], NULL);
+ if (r < 0)
+ return r;
+ }
+
+ DNS_PACKET_HEADER(p)->qdcount = htobe16(q->n_keys);
+ }
+
+ if (answer) {
+ for (i = 0; i < answer->n_rrs; i++) {
+ r = dns_packet_append_rr(p, answer->rrs[i], NULL);
+ if (r < 0)
+ return r;
+ }
+
+ DNS_PACKET_HEADER(p)->ancount = htobe16(answer->n_rrs);
+ }
+
+ if (soa) {
+ for (i = 0; i < soa->n_rrs; i++) {
+ r = dns_packet_append_rr(p, soa->rrs[i], NULL);
+ if (r < 0)
+ return r;
+ }