diff options
| author | Igor Pstyga <[email protected]> | 2024-04-23 21:04:52 -0700 |
|---|---|---|
| committer | git <[email protected]> | 2024-08-13 21:09:08 +0000 |
| commit | 4be9b72fbb44e7754337f4957f2c7bfe3cd41891 () | |
| tree | f5ddaf35adeec45d3a31d85f1932dc9b754c4dd7 /lib/resolv.rb | |
| parent | 525008cd7879a047e3c310eb63dcef901b23be56 (diff) | |
[ruby/resolv] Fix TCP fallback with multiple nameservers
Under the following conditions the exception `Resolv::DNS::Requester::RequestError: host/port don't match` is raised: - Multiple nameservers are configured for Resolv::DNS - A nameserver falls back from UDP to TCP - TCP request hits Resolv::DNS timeout - Resolv::DNS retries the next nameserver More details here https://bugs.ruby-lang.org/issues/8285 https://.com/ruby/resolv/commit/7d524df80e Co-authored-by: Julian Mehnle <[email protected]>
| -rw-r--r-- | lib/resolv.rb | 47 |
1 files changed, 27 insertions, 20 deletions
@@ -513,22 +513,32 @@ class Resolv def fetch_resource(name, typeclass) lazy_initialize - begin - requester = make_udp_requester - rescue Errno::EACCES - # fall back to TCP - end senders = {} begin - @config.resolv(name) {|candidate, tout, nameserver, port| - requester ||= make_tcp_requester(nameserver, port) msg = Message.new msg.rd = 1 msg.add_question(candidate, typeclass) - unless sender = senders[[candidate, nameserver, port]] sender = requester.sender(msg, candidate, nameserver, port) next if !sender - senders[[candidate, nameserver, port]] = sender end reply, reply_name = requester.request(sender, tout) case reply.rcode @@ -536,12 +546,7 @@ class Resolv if reply.tc == 1 and not Requester::TCP === requester requester.close # Retry via TCP: - requester = make_tcp_requester(nameserver, port) - senders = {} - # This will use TCP for all remaining candidates (assuming the - # current candidate does not already respond successfully via - # TCP). This makes sense because we already know the full - # response will not fit in an untruncated UDP packet. redo else yield(reply, reply_name) @@ -552,9 +557,9 @@ class Resolv else raise Config::OtherResolvError.new(reply_name.to_s) end - } ensure - requester&.close end end @@ -569,6 +574,11 @@ class Resolv def make_tcp_requester(host, port) # :nodoc: return Requester::TCP.new(host, port) end def extract_resources(msg, name, typeclass) # :nodoc: @@ -1800,7 +1810,6 @@ class Resolv end end - ## # Base class for SvcParam. [RFC9460] @@ -2499,7 +2508,6 @@ class Resolv attr_reader :altitude - def encode_rdata(msg) # :nodoc: msg.put_bytes(@version) msg.put_bytes(@ssize.scalar) @@ -3439,4 +3447,3 @@ class Resolv AddressRegex = /(?:#{IPv4::Regex})|(?:#{IPv6::Regex})/ end - |