NAME
Net::DNS::ToolKit::RR::SOA - Resource Record Handler
SYNOPSIS
DO NOT use Net::DNS::ToolKit::RR::SOA
DO NOT require Net::DNS::ToolKit::RR::SOA
Net::DNS::ToolKit::RR::SOA is autoloaded by
class Net::DNS::ToolKit::RR and its methods
are instantiated in a 'special' manner.
use Net::DNS::ToolKit::RR;
($get,$put,$parse) = new Net::DNS::ToolKit::RR;
($newoff,$name,$type,$class,$ttl,$rdlength,
) = $get->SOA(\$buffer,$offset);
Note: the $get->SOA method is normally called
via: @stuff = $get->next(\$buffer,$offset);
($newoff,@dnptrs)=$put->SOA(\$buffer,$offset,\@dnptrs,
$name,$type,$class,$ttl,
$mname,$rname,$serial,$refresh,$retry,$expire,$min);
$NAME,$TYPE,$CLASS,$TTL,$rdlength,
$MNAME,$RNAME,$serial,$refresh,$retry,$expire,$min)
= $parse->SOA($name,$type,$class,$ttl,$rdlength,
$mname,$rname,$serial,$refresh,$retry,$expire,$min);DESCRIPTION
Net::DNS::ToolKit::RR:SOA appends an SOA resource record to a DNS packet under construction, recovers an SOA resource record from a packet being decoded, and converts the numeric/binary portions of the resource record to human readable form.
Description from RFC1035.txt
3.2.1. Format
All RRs have the same top level format shown below:
1 1 1 1 1 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| NAME |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| TYPE |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| CLASS |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| TTL |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| RDLENGTH |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--|
| RDATA |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
NAME an owner name, i.e., the name of the node to which this
resource record pertains.
TYPE two octets containing one of the RR TYPE codes.
CLASS two octets containing one of the RR CLASS codes.
TTL a 32 bit signed integer that specifies the time interval
that the resource record may be cached before the source
of the information should again be consulted. Zero
values are interpreted to mean that the RR can only be
used for the transaction in progress, and should not be
cached. For example, SOA records are always distributed
with a zero TTL to prohibit caching. Zero values can
also be used for extremely volatile data.
RDLENGTH an unsigned 16 bit integer that specifies the length
in octets of the RDATA field.
RDATA a variable length string of octets that describes the
resource. The format of this information varies
according to the TYPE and CLASS of the resource record.
3.3.13. SOA RDATA format
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/ MNAME /
/ /
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/ RNAME /
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| SERIAL |
| |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| REFRESH |
| |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| RETRY |
| |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| EXPIRE |
| |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| MINIMUM |
| |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
where:
MNAME The <domain-name> of the name server that was
the original or primary source of data for this
zone.
RNAME A <domain-name> which specifies the mailbox of
the person responsible for this zone.
SERIAL The unsigned 32 bit version number of the
original copy of the zone. Zone transfers
preserve this value. This value wraps and
should be compared using sequence space
arithmetic.
REFRESH A 32 bit time interval before the zone
should be refreshed.
RETRY A 32 bit time interval that should elapse
before a failed refresh should be retried.
EXPIRE A 32 bit time value that specifies the upper
limit on the time interval that can elapse
before the zone is no longer authoritative.
MINIMUM The unsigned 32 bit minimum TTL field that
should be exported with any RR from this zone.SOA records cause no additional section processing.
All times are in units of seconds.
Most of these fields are pertinent only for name server maintenance operations. However, MINIMUM is used in all query operations that retrieve RRs from a zone. Whenever a RR is sent in a response to a query, the TTL field is set to the maximum of the TTL field from the RR and the MINIMUM field in the appropriate SOA. Thus MINIMUM is a lower bound on the TTL field for all RRs in a zone. Note that this use of MINIMUM should occur when the RRs are copied into the response and not when the zone is loaded from a master file or via a zone transfer. The reason for this provison is to allow future dynamic update facilities to change the SOA RR with known semantics.
@stuff = $get->SOA(\$buffer,$offset);
Get the contents of the resource record. USE: @stuff = $get->next(\$buffer,$offset); where: @stuff = ( $newoff $name,$type,$class,$ttl,$rdlength, $mname,$rname,$serial,$refresh,$retry,$expire,$min);All except the last five (5) items, $mname,$rname,$serial,$refresh,$retry,$expire,$min, are provided by the class loader, Net::DNS::ToolKit::RR. The code in this method knows how to retrieve $mname,$rname,$serial,$refresh,$retry,$expire,$min.
input: pointer to buffer, offset into buffer returns: offset to next resource, @common RR elements, primary server name, zone contact, RR serial number, REFRESH timer, RETRY timer, EXPIRE timer, MINIMUM ttl($newoff,@dnptrs)=$put->SOA(\$buffer,$offset,\@dnptrs, $name,$type,$class,$ttl, $mname,$rname,$serial,$refresh,$retry,$expire,$min);
Append an SOA record to $buffer.
where @common = ( $name,$type,$class,$ttl);The method will insert the $rdlength, $mname, $rname, $serial, $refresh, $retry, $expire, and $min, then return the updated pointer to the array of compressed names
The class loader, Net::DNS::ToolKit::RR, inserts the @common elements and returns updated @dnptrs. This module knows how to insert its RDATA and calculate the $rdlength.
input: pointer to buffer, offset (normally end of buffer), pointer to compressed name array, @common RR elements, primary server name, zone contact, RR serial number, REFRESH timer, RETRY timer, EXPIRE timer, MINIMUM ttl output: offset to next RR, new compressed name pointer array, or empty list () on error.(@COMMON,$MNAME,$RNAME,$serial,$refresh,$retry,$expire,$min) = $parse->A(@common, $mname,$rname,$serial,$refresh,$retry,$expire,$min);
Converts binary/numeric field data into human readable form. The common RR elements are supplied by the class loader, Net::DNS::ToolKit::RR. For SOA RR's, this returns $mxdname terminated with '.'
input: primary server name, zone contact, serial number, refresh timer, retry timer, expire timer, minimum ttl returns: SERVER NAME '.' terminated CONTACT NAME '.' terminated serial number, refresh timer, retry timer, expire timer, minimum ttl
DEPENDENCIES
Net::DNS::ToolKit
Net::DNS::CodesEXPORT
noneAUTHOR
Michael Robinton <michael@bizsystems.com>
COPYRIGHT
Copyright 2003 - 2011, Michael Robinton <michael@bizsystems.com>Michael Robinton <michael@bizsystems.com>
All rights reserved.
This program is free software; you can redistribute it and/or modify it under the terms of either:
a) the GNU General Public License as published by the Free
Software Foundation; either version 2, or (at your option) any
later version, or
b) the "Artistic License" which comes with this distribution.This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See either the GNU General Public License or the Artistic License for more details.
You should have received a copy of the Artistic License with this distribution, in the file named "Artistic". If not, I'll be glad to provide one.
You should also have received a copy of the GNU General Public License along with this program in the file named "Copying". If not, write to the
Free Software Foundation, Inc.
59 Temple Place, Suite 330
Boston, MA 02111-1307, USA or visit their web page on the internet at:
http://www.gnu.org/copyleft/gpl.html.See also:
Net::DNS::Codes(3), Net::DNS::ToolKit(3)