DNS::ZoneParse - Parse and manipulate DNS Zone Files.

    use DNS::ZoneParse;

    my $zonefile = DNS::ZoneParse->new("/path/to/dns/zonefile.db", $origin);

    # Get a reference to the MX records
    my $mx = $zonefile->mx;

    # Change the first mailserver on the list
    $mx->[0] = { host => 'mail.localhost.com',
                 priority => 10,
                 name => '@' };

    # update the serial number
    $zonefile->new_serial();

    # write the new zone file to disk 
    open NEWZONE, ">/path/to/dns/zonefile.db" or die "error";
    print NEWZONE $zonefile->output();
    close NEWZONE;

   perl Makefile.PL
   make
   make test
   make install

Win32 users substitute make with nmake or equivalent. nmake is available at http://download.microsoft.com/download/vc15/Patch/1.52/W95/EN-US/Nmake15.exe

This module will parse a Zone File and put all the Resource Records (RRs) into an anonymous hash structure. At the moment, the following types of RRs are supported: SOA, NS, MX, A, CNAME, TXT, PTR. It could be useful for maintaining DNS zones, or for transferring DNS zones to other servers. If you want to generate an XML-friendly version of your zone files, it is easy to use XML::Simple with this module once you have parsed the zonefile.

DNS::ZoneParse scans the DNS zonefile - removes comments and seperates the file into its constituent records. It then parses each record and stores the records internally. See below for information on the accessor methods.

new

This creates the DNS::ZoneParse Object and loads the zonefile Example: my CW$zonefile = DNS::ZoneParse->new(/path/to/zonefile.db); You can also initialise the object with the contents of a file: my CW$zonefile = DNS::ZoneParse->new( \$zone_contents ); You can pass a second, optional parameter to the constructor to supply an CW$origin if none can be found in the zone file.

    my $zonefile = DNS::ZoneParse->new( \$zone_contents, $origin );

a(), cname(), mx(), ns(), ptr()

These methods return references to the resource records. For example:

    my $mx = $zonefile->mx;

Returns the mx records in an array reference. A, CNAME, NS, MX and PTR records have the following properties: 'ttl', 'class', 'host', 'name' MX records also have a 'priority' property.

soa()

Returns a hash reference with the following properties: 'serial', 'origin', 'primary', 'refresh', 'retry', 'ttl', 'minimumTTL', 'email', 'expire'

dump

Returns a copy of the datastructute that stores all the resource records. This might be useful if you want to quickly transform the data into another format, such as XML.

new_serial

CWnew_serial() incriments the Zone serial number. It will generate a date-based serial number. Or you can pass a positive number to add to the current serial number. Examples:

    $zonefile->new_serial();    # generates a new serial number based on date:
                               # YYYYmmddHH format, incriments current serial
                               # by 1 if the new serial is still smaller

    $zonefile->new_serial(5);  # adds 50 to the original serial number

output

CWoutput() returns the new zonefile output as a string. If you wish your output formatted differently, you can pass the output of CWdump() to your favourite templating module.

This script will print the A records in a zone file, add a new A record for the name new and then return the zone file.

    use strict;
    use DNS::ZoneParse;

    my $zonefile = DNS::ZoneParse->new("/path/to/zonefile.db");

    print "Current A Records\n";
    my $a_records = $zonefile->a();

    foreach my $record (@$a_records) {
        print "$record->{name} resolves at $record->{host}\n";
    }

    push (@$a_records, { name => 'new', class => 'IN',
                         host => '127.0.0.1', ttl => '' });

    $zonefile->new_serial();
    my $newfile = $zonefile->output();

This script will convert a DNS Zonefile to an XML file using XML::Simple.

    use strict;
    use DNS::ZoneParse;
    use XML::Simple;

    my $zonefile = DNS::ZoneParse->new("/path/to/zonefile.db");

    my $new_xml = XMLout($zonefile->dump,
                         noattr => 1,
                         suppressempty => 1,
                         rootname => $zonefile->origin);

see Changes

The DNS::ZoneParse API may change in future versions. At present, the parsing is not as strict as it should be and support for CW$ORIGIN and CW$TTL is quite basic. It would also be nice to support the CWINCLUDE statement. Furthermore, parsing large zonefiles with thousands of records can use lots of memory - some people have requested a callback interface.

I can squash more bugs with your help. Please let me know if you spot something that doesn't work as expected.

You can report bugs via the CPAN RT: <http://rt.cpan.org/NoAuth/Bugs.html?Dist=DNS-ZoneParse>

If possible, please provide a diff against t/dns-zoneparse.t and t/test-zone.db that demonstrates the bug(s).

Other modules with similar functionality:

Net::DNS::ZoneParser, Net::DNS::ZoneFile, DNS::ZoneFile

Simon Flack

DNS::ZoneParse is free software which you can redistribute and/or modify under the same terms as Perl itself.