package Net::DNS::ToolKit::RR::MINFO; use strict; #use warnings; use Net::DNS::ToolKit qw( get16 get32 put16 put32 dn_comp dn_expand ); use Net::DNS::Codes qw(:constants); use vars qw($VERSION); $VERSION = do { my @r = (q$Revision: 0.01 $ =~ /\d+/g); sprintf "%d."."%02d" x $#r, @r }; =head1 NAME Net::DNS::ToolKit::RR::MINFO - Resource Record Handler =head1 SYNOPSIS DO NOT use Net::DNS::ToolKit::RR::MINFO DO NOT require Net::DNS::ToolKit::RR::MINFO Net::DNS::ToolKit::RR::MINFO is autoloaded by class Net::DNS::ToolKit::RR and its methods are instantiated in a 'special' manner. use Net::DNS::ToolKit::RR; ($get,$put,$parse) = new Net::DNS::ToolKit::RR; ($newoff,$name,$type,$class,$ttl,$rdlength, ) = $get->MINFO(\$buffer,$offset); Note: the $get->MINFO method is normally called via: @stuff = $get->next(\$buffer,$offset); ($newoff,@dnptrs)=$put->MINFO(\$buffer,$offset,\@dnptrs, $name,$type,$class,$ttl, $mname,$errname); $NAME,$TYPE,$CLASS,$TTL,$rdlength, $MNAME,$RNAME,$serial,$refresh,$retry,$expire,$min) = $parse->MINFO($name,$type,$class,$ttl,$rdlength, $mname,$errname); =head1 DESCRIPTION B appends an MINFO resource record to a DNS packet under construction, recovers an MINFO 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, MINFO 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. MINFO RDATA format +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ / RMAILBX / +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ / EMAILBX / +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ where: RMAILBX A which specifies a mailbox which is responsible for the mailing list or mailbox. If this domain name names the root, the owner of the MINFO RR is responsible for itself. Note that many existing mailing lists use a mailbox X-request for the RMAILBX field of mailing list X, e.g., Msgroup-request for Msgroup. This field provides a more general mechanism. EMAILBX A which specifies a mailbox which is to receive error messages related to the mailing list or mailbox specified by the owner of the MINFO RR (similar to the ERRORS-TO: field which has been proposed). If this domain name names the root, errors should be returned to the sender of the message. MINFO records cause no additional section processing. =over 4 =item * @stuff = $get->MINFO(\$buffer,$offset); Get the contents of the resource record. USE: @stuff = $get->next(\$buffer,$offset); where: @stuff = ( $newoff $name,$type,$class,$ttl,$rdlength, $rname,$errname); All except the last five (2) items, B<$mname,$errname>, are provided by the class loader, B. The code in this method knows how to retrieve B<$mname,$errname>. input: pointer to buffer, offset into buffer returns: offset to next resource, @common RR elements, responsible.mail.box error.mail.box =cut sub get { my($self,$bp,$offset) = @_; $offset += INT16SZ; # don't need rdlength ($offset, my $mname) = dn_expand($bp,$offset); ($offset, my $errname) = dn_expand($bp,$offset); return($offset,$mname,$errname); } =item * ($newoff,@dnptrs)=$put->MINFO(\$buffer,$offset,\@dnptrs, $name,$type,$class,$ttl, $mname,$errname); Append an MINFO record to $buffer. where @common = ( $name,$type,$class,$ttl); The method will insert the $rdlength, $mname, $errname then return the updated pointer to the array of compressed names The class loader, B, inserts the @common elements and returns updated @dnptrs. This module knows how to insert its RDATA and calculate the $rdlength. input: pointer to buffer, offset (normally end of buffer), pointer to compressed name array, @common RR elements, responsible.mail.box error.mail.box output: offset to next RR, new compressed name pointer array, or empty list () on error. =cut sub put { return () unless @_; # always return on error my($self,$bp,$off,$dnp,$mname,$errname) = @_; my $rdlp = $off; # save pointer to rdlength my ($doff,@dnptrs); # data start, pointer array return () unless # check for valid and get ($doff = put16($bp,$off,0)) && # offset for names (($off,@dnptrs) = dn_comp($bp,$doff,\$mname,$dnp)) && (($off,@dnptrs) = dn_comp($bp,$off,\$errname,\@dnptrs)); # rdlength = new offset - previous offset put16($bp,$rdlp, $off - $doff); return($off,@dnptrs); } =item * (@COMMON,$MNAME,$ERRNAME) = $parse->A(@common, $mname,$errname); Converts binary/numeric field data into human readable form. The common RR elements are supplied by the class loader, B. For MINFO RR's, this returns $mxdname terminated with '.' input: responsible.mail.box error.mail.box returns: responsible.mail.box '.' terminated error.mail.box '.' terminated =back =cut sub parse { my($self,$mname,$errname) = @_; return($mname.'.',$errname.'.'); } =head1 DEPENDENCIES Net::DNS::ToolKit Net::DNS::Codes =head1 EXPORT none =head1 AUTHOR Michael Robinton =head1 COPYRIGHT Copyright 2006, Michael Robinton This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. 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 the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. =head1 See also: Net::DNS::Codes(3), Net::DNS::ToolKit(3) =cut 1;