diff options
| -rw-r--r-- | src/resolve/resolved-dns-scope.c | 6 | ||||
| -rw-r--r-- | src/resolve/resolved-dns-transaction.c | 1 | ||||
| -rw-r--r-- | src/resolve/resolved-mdns.c | 12 |
3 files changed, 13 insertions, 6 deletions
diff --git a/src/resolve/resolved-dns-scope.c b/src/resolve/resolved-dns-scope.c index ac44cf2343..61bca04b94 100644 --- a/src/resolve/resolved-dns-scope.c +++ b/src/resolve/resolved-dns-scope.c @@ -822,7 +822,11 @@ static int dns_scope_make_conflict_packet( 0 /* (ad) */, 0 /* (cd) */, 0)); - random_bytes(&DNS_PACKET_HEADER(p)->id, sizeof(uint16_t)); + + /* For mDNS, the transaction ID should always be 0 */ + if (s->protocol != DNS_PROTOCOL_MDNS) + random_bytes(&DNS_PACKET_HEADER(p)->id, sizeof(uint16_t)); + DNS_PACKET_HEADER(p)->qdcount = htobe16(1); DNS_PACKET_HEADER(p)->arcount = htobe16(1); diff --git a/src/resolve/resolved-dns-transaction.c b/src/resolve/resolved-dns-transaction.c index efed761001..c03aa5d287 100644 --- a/src/resolve/resolved-dns-transaction.c +++ b/src/resolve/resolved-dns-transaction.c @@ -919,7 +919,6 @@ static int dns_transaction_make_packet_mdns(DnsTransaction *t) { } DNS_PACKET_HEADER(p)->qdcount = htobe16(qdcount); - DNS_PACKET_HEADER(p)->id = t->id; /* Append known answer section if we're asking for any shared record */ if (add_known_answers) { diff --git a/src/resolve/resolved-mdns.c b/src/resolve/resolved-mdns.c index abe63d58c1..d6973a6999 100644 --- a/src/resolve/resolved-mdns.c +++ b/src/resolve/resolved-mdns.c @@ -86,7 +86,7 @@ static int on_mdns_packet(sd_event_source *s, int fd, uint32_t revents, void *us } if (dns_packet_validate_reply(p) > 0) { - unsigned i; + DnsResourceRecord *rr; log_debug("Got mDNS reply packet"); @@ -107,11 +107,15 @@ static int on_mdns_packet(sd_event_source *s, int fd, uint32_t revents, void *us dns_scope_check_conflicts(scope, p); - for (i = 0; i < p->answer->n_rrs; i++) { - DnsResourceRecord *rr; + DNS_ANSWER_FOREACH(rr, p->answer) { + const char *name = DNS_RESOURCE_KEY_NAME(rr->key); DnsTransaction *t; - rr = p->answer->items[i].rr; + /* If the received reply packet contains ANY record that is not .local or .in-addr.arpa, + * we assume someone's playing tricks on us and discard the packet completely. */ + if (!(dns_name_endswith(name, "in-addr.arpa") > 0 || + dns_name_endswith(name, "local") > 0)) + return 0; t = dns_scope_find_transaction(scope, rr->key, false); if (t) |