summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorDaniel Mack <daniel@zonque.org>2015-09-03 12:09:11 +0200
committerDaniel Mack <daniel@zonque.org>2015-12-08 16:51:41 +0100
commit547493c5ad5c82032e247609970f96be76c2d661 (patch)
tree7ae351c13f032b59ae1b95a5a15227b0732beb90
parenta20b9592178ff728ddeefa13c77e00be91af14c4 (diff)
resolved: handle more mDNS protocol details
-rw-r--r--src/resolve/resolved-dns-transaction.c55
1 files changed, 32 insertions, 23 deletions
diff --git a/src/resolve/resolved-dns-transaction.c b/src/resolve/resolved-dns-transaction.c
index 22ea88ab0b..22a7a5340c 100644
--- a/src/resolve/resolved-dns-transaction.c
+++ b/src/resolve/resolved-dns-transaction.c
@@ -458,6 +458,13 @@ void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) {
}
if (DNS_PACKET_TC(p)) {
+
+ /* Truncated packets for mDNS are not allowed. Give up immediately. */
+ if (t->scope->protocol == DNS_PROTOCOL_MDNS) {
+ dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);
+ return;
+ }
+
/* Response was truncated, let's try again with good old TCP */
r = dns_transaction_open_tcp(t);
if (r == -ESRCH) {
@@ -466,7 +473,7 @@ void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) {
return;
}
if (r < 0) {
- /* On LLMNR, if we cannot connect to the host,
+ /* On LLMNR and mDNS, if we cannot connect to the host,
* we immediately give up */
if (t->scope->protocol == DNS_PROTOCOL_LLMNR) {
dns_transaction_complete(t, DNS_TRANSACTION_RESOURCES);
@@ -493,29 +500,31 @@ void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) {
return;
}
- /* Only consider responses with equivalent query section to the request */
- if (p->question->n_keys != 1 || dns_resource_key_equal(p->question->keys[0], t->key) <= 0) {
- dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);
- return;
- }
+ if (t->scope->protocol == DNS_PROTOCOL_DNS) {
+ /* Only consider responses with equivalent query section to the request */
+ if (p->question->n_keys != 1 || dns_resource_key_equal(p->question->keys[0], t->key) <= 0) {
+ dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);
+ return;
+ }
- /* Install the answer as answer to the transaction */
- dns_answer_unref(t->answer);
- t->answer = dns_answer_ref(p->answer);
- t->answer_rcode = DNS_PACKET_RCODE(p);
- t->answer_authenticated = t->scope->dnssec_mode == DNSSEC_TRUST && DNS_PACKET_AD(p);
-
- /* According to RFC 4795, section 2.9. only the RRs from the answer section shall be cached */
- if (DNS_PACKET_SHALL_CACHE(p))
- dns_cache_put(&t->scope->cache,
- t->key,
- DNS_PACKET_RCODE(p),
- p->answer,
- DNS_PACKET_ANCOUNT(p),
- t->answer_authenticated,
- 0,
- p->family,
- &p->sender);
+ /* Install the answer as answer to the transaction */
+ dns_answer_unref(t->answer);
+ t->answer = dns_answer_ref(p->answer);
+ t->answer_rcode = DNS_PACKET_RCODE(p);
+ t->answer_authenticated = t->scope->dnssec_mode == DNSSEC_TRUST && DNS_PACKET_AD(p);
+
+ /* According to RFC 4795, section 2.9. only the RRs from the answer section shall be cached */
+ if (DNS_PACKET_SHALL_CACHE(p))
+ dns_cache_put(&t->scope->cache,
+ t->key,
+ DNS_PACKET_RCODE(p),
+ p->answer,
+ DNS_PACKET_ANCOUNT(p),
+ t->answer_authenticated,
+ 0,
+ p->family,
+ &p->sender);
+ }
if (DNS_PACKET_RCODE(p) == DNS_RCODE_SUCCESS)
dns_transaction_complete(t, DNS_TRANSACTION_SUCCESS);