DNS::Zonefile

The format of a DNS Zonefile is defined in RFC 1035 section 5 and RFC 1034 section 3.6.1. To anyone who’s using BIND they’ll look very familiar.

This is an attempt to use Ruby parse them into an object graph which can be investigated programatically, manipulated, validated or printed into some canonical form.

Getting setup


Well, you’ll need the treetop and polyglot gems installed. They do all the hard work. Thanks!

sudo gem install treetop polyglot

Now you’ll need to generate the Treetop parser from the Zonefile grammar that I’ve hacked together.

rake generate_grammar

Okay, you’re ready to move onto the examples now.

The above steps should not be necessary if you install the gem via rubygems.

Examples


Using raw data from the parser. Note that “@” isn’t translated in this mode. Nor are inherited TTLs interpreted.

zonefile = "/path/to/file.zone"
zone_string = File.read(zonefile)
zone = DNS::Zonefile.parse(zone_string)

puts zone.soa.origin.to_s
puts zone.soa.ns.to_s
puts zone.rr[0].to_s

Using more structure data. @, TTLs, and empty hostname inheritance are all handled in this mode.

zonefile = "/path/to/file.zone"
zone_string = File.read(zonefile)
zone = DNS::Zonefile.load(zone_string)
# or, if no $origin is in the zone file
zone = DNS::Zonefile.load(zone_string, 'example.com.')

puts zone.soa.origin
puts zone.soa.nameserver
puts zone.records[1]
# get all MX records
puts zone.records_of(DNS::MX)

Authors


Original code and concept: Craig R Webster <barkingiguana.com/>

Additions: t.e.morgan <zerigo.com/>

Contributing


See the TODO. Send me patches or pull request either by email or on GitHub.