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| author | Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl> | 2017-02-12 15:38:51 -0500 |
|---|---|---|
| committer | Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl> | 2017-02-12 15:38:51 -0500 |
| commit | 01c901e257521a7a3ff6fc5945a3e5a4a7409a94 (patch) | |
| tree | 5cddf7c13988f6e96ef18fa7638e35dce0e26c8e /src/resolve/resolved-mdns.c | |
| parent | 9606bc4b4b09a4d1bff3f047d5ca5ac4cf3fe073 (diff) | |
| parent | fa8b44999406ace5f44376c1be1c75edfdde5a03 (diff) | |
Merge pull request #4832 from rojkov/mdns
Diffstat (limited to 'src/resolve/resolved-mdns.c')
| -rw-r--r-- | src/resolve/resolved-mdns.c | 61 |
1 files changed, 60 insertions, 1 deletions
diff --git a/src/resolve/resolved-mdns.c b/src/resolve/resolved-mdns.c index b13b1d0144..f5cae6f682 100644 --- a/src/resolve/resolved-mdns.c +++ b/src/resolve/resolved-mdns.c @@ -67,6 +67,52 @@ eaddrinuse: return 0; } +static int mdns_scope_process_query(DnsScope *s, DnsPacket *p) { + _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL, *soa = NULL; + _cleanup_(dns_packet_unrefp) DnsPacket *reply = NULL; + DnsResourceKey *key = NULL; + bool tentative = false; + int r; + + assert(s); + assert(p); + + r = dns_packet_extract(p); + if (r < 0) { + log_debug_errno(r, "Failed to extract resource records from incoming packet: %m"); + return r; + } + + /* TODO: there might be more than one question in mDNS queries. */ + assert_return((dns_question_size(p->question) > 0), -EINVAL); + key = p->question->keys[0]; + + r = dns_zone_lookup(&s->zone, key, 0, &answer, &soa, &tentative); + if (r < 0) { + log_debug_errno(r, "Failed to lookup key: %m"); + return r; + } + if (r == 0) + return 0; + + r = dns_scope_make_reply_packet(s, DNS_PACKET_ID(p), DNS_RCODE_SUCCESS, NULL, answer, NULL, false, &reply); + if (r < 0) { + log_debug_errno(r, "Failed to build reply packet: %m"); + return r; + } + + if (!ratelimit_test(&s->ratelimit)) + return 0; + + r = dns_scope_emit_udp(s, -1, reply); + if (r < 0) { + log_debug_errno(r, "Failed to send reply packet: %m"); + return r; + } + + return 0; +} + static int on_mdns_packet(sd_event_source *s, int fd, uint32_t revents, void *userdata) { _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL; Manager *m = userdata; @@ -77,6 +123,9 @@ static int on_mdns_packet(sd_event_source *s, int fd, uint32_t revents, void *us if (r <= 0) return r; + if (manager_our_packet(m, p)) + return 0; + scope = manager_find_scope(m, p); if (!scope) { log_warning("Got mDNS UDP packet on unknown scope. Ignoring."); @@ -115,6 +164,12 @@ static int on_mdns_packet(sd_event_source *s, int fd, uint32_t revents, void *us dns_name_endswith(name, "local") > 0)) return 0; + if (rr->ttl == 0) { + log_debug("Got a goodbye packet"); + /* See the section 10.1 of RFC6762 */ + rr->ttl = 1; + } + t = dns_scope_find_transaction(scope, rr->key, false); if (t) dns_transaction_process_reply(t, p); @@ -125,7 +180,11 @@ static int on_mdns_packet(sd_event_source *s, int fd, uint32_t revents, void *us } else if (dns_packet_validate_query(p) > 0) { log_debug("Got mDNS query packet for id %u", DNS_PACKET_ID(p)); - dns_scope_process_query(scope, NULL, p); + r = mdns_scope_process_query(scope, p); + if (r < 0) { + log_debug("mDNS query processing failed."); + return 0; + } } else log_debug("Invalid mDNS UDP packet."); |