Bug #12372: Resolv::DNS does not fetch authority section resources when calling getresource(s)

• Status: Closed
• Assignee: -
• Target version: -
• ruby -v: All versions (1.1.8 - trunk)
• Backport: 2.1: UNKNOWN, 2.2: UNKNOWN, 2.3: UNKNOWN

[ereslibre (Rafael Fernández López)]

In some cases, for example, when trying to retrieve the nameservers of a domain, you need to ask authoritative servers:

> dig ns org
(...)
;; ANSWER SECTION:
org.			13729	IN	NS	a0.org.afilias-nst.info.
org.			13729	IN	NS	a2.org.afilias-nst.info.
org.			13729	IN	NS	b0.org.afilias-nst.org.
org.			13729	IN	NS	b2.org.afilias-nst.org.
org.			13729	IN	NS	c0.org.afilias-nst.info.
org.			13729	IN	NS	d0.org.afilias-nst.org.

(pick one)

> dig ns ruby-lang.org @a0.org.afilias-nst.info
(...)
;; AUTHORITY SECTION:
ruby-lang.org.		86400	IN	NS	pichu.netlab.jp.
ruby-lang.org.		86400	IN	NS	support.netlab.jp.

The last reply (that returns the nameserver of the ruby-lang.org domain) comes in the authority section of the DNS message reply. Doing this with Resolv::DNS is very tricky right now:

require 'resolv'
dns = Resolv::DNS.new(:nameserver => ['199.19.56.1'])
puts dns.getresources('ruby-lang.org', Resolv::DNS::Resource::IN::NS).map(&:name)

Resolv::DNS is internally calling on extract_resources to each_answer, which only fetches the answer part of the DNS message reply. I created a pull request some time ago (https://github.com/ruby/ruby/pull/797), so it would internally call each_resource that internally collects each_answer, each_authority and each_additional.

[ereslibre (Rafael Fernández López)]

• ruby -v set to All versions (1.1.8 - trunk)

[headius (Charles Nutter)]

Thumbs up from JRuby. We'll merge this in when ruby-core agrees.

[headius (Charles Nutter)]

Ping again.

[akr (Akira Tanaka)]

• Status changed from Open to Closed

fixed at r56583