#
# $Id: Lsa.pm,v 1.9 2007/03/13 18:19:52 gomor Exp $
#
package Net::Frame::Layer::OSPF::Lsa;
use strict;
use warnings;
use Net::Frame::Layer qw(:consts :subs);
our @ISA = qw(Net::Frame::Layer);
our @AS = qw(
lsAge
options
lsType
linkStateId
advertisingRouter
lsSequenceNumber
lsChecksum
length
lsa
full
);
__PACKAGE__->cgBuildIndices;
__PACKAGE__->cgBuildAccessorsScalar(\@AS);
use Net::Frame::Layer::OSPF qw(:consts);
require Net::Frame::Layer::OSPF::Lsa::Opaque;
require Net::Frame::Layer::OSPF::Lsa::Router;
require Net::Frame::Layer::OSPF::Lsa::Network;
require Net::Frame::Layer::OSPF::Lsa::SummaryIp;
sub new {
shift->SUPER::new(
lsAge => 30,
options => 0,
lsType => NF_OSPF_LSTYPE_ROUTER,
linkStateId => '0.0.0.0',
advertisingRouter => '0.0.0.0',
lsSequenceNumber => 0,
lsChecksum => 0,
length => NF_OSPF_LSA_HDR_LEN,
full => 1,
@_,
);
}
# Lsa begins with standard 20 bytes header
sub getLength {
my $self = shift;
my $len = NF_OSPF_LSA_HDR_LEN;
$len += $self->lsa->getLength if $self->lsa;
$len;
}
sub computeLengths {
my $self = shift;
my $len = $self->getLength;
$self->length($len);
}
sub computeChecksums {
my $self = shift;
$self->lsChecksum(0);
my $raw = $self->pack;
my $data = substr($raw, 2);
# We pad the data to the possibly fake length
my @chars = unpack('C*', $data.("0"x($self->length - length($data))));
my $c0 = 0;
my $c1 = 0;
my $length = $self->length - 2;
my $MODX = 4102;
my ($sp, $ep, $p, $q);
$sp = 0;
for ($ep = $length; $sp < $ep; $sp = $q) {
$q = $sp + $MODX;
if ($q > $ep) {
$q = $ep;
}
for ($p = $sp; $p < $q; $p++) {
$c0 += $chars[$p];
$c1 += $c0;
}
$c0 %= 255;
$c1 %= 255;
}
my $x = (($length - 15) * $c0 - $c1) % 255;
if ($x <= 0) {
$x += 255;
}
my $y = 510 - $c0 - $x;
if ($y > 255) {
$y -= 255;
}
$self->lsChecksum(($x << 8) + $y);
}
sub pack {
my $self = shift;
my $raw = $self->SUPER::pack('nCCa4a4Nnn a*',
$self->lsAge, $self->options, $self->lsType, inetAton($self->linkStateId),
inetAton($self->advertisingRouter), $self->lsSequenceNumber,
$self->lsChecksum, $self->length,
) or return undef;
$raw .= $self->lsa->pack if $self->lsa;
$self->raw($raw);
}
sub unpack {
my $self = shift;
my ($lsAge, $options, $lsType, $linkStateId, $advertisingRouter,
$lsSequenceNumber, $lsChecksum, $length, $payload)
= $self->SUPER::unpack('nCCa4a4Nnn a*', $self->raw)
or return undef;
$self->lsAge($lsAge);
$self->options($options);
$self->lsType($lsType);
$self->linkStateId(inetNtoa($linkStateId));
$self->advertisingRouter(inetNtoa($advertisingRouter));
$self->lsSequenceNumber($lsSequenceNumber);
$self->lsChecksum($lsChecksum);
$self->length($length);
my $next;
if ($self->full && $payload) {
if ($lsType == NF_OSPF_LSTYPE_OPAQUELINKLOCAL
|| $lsType == NF_OSPF_LSTYPE_OPAQUEAREALOCAL
|| $lsType == NF_OSPF_LSTYPE_OPAQUEDOMAIN) {
my $pLen = length($payload);
if ($length > $pLen) {
my $oLen = $length - NF_OSPF_LSA_HDR_LEN;
my $opaque = substr($payload, 0, $oLen);
$next = Net::Frame::Layer::OSPF::Lsa::Opaque->new(raw => $opaque);
$payload = substr($payload, $oLen);
$next->payload($payload);
}
}
elsif ($lsType == NF_OSPF_LSTYPE_ROUTER) {
$next = Net::Frame::Layer::OSPF::Lsa::Router->new(raw => $payload);
}
elsif ($lsType == NF_OSPF_LSTYPE_NETWORK) {
$next = Net::Frame::Layer::OSPF::Lsa::Network->new(raw => $payload);
}
elsif ($lsType == NF_OSPF_LSTYPE_SUMMARYIP) {
$next = Net::Frame::Layer::OSPF::Lsa::SummaryIp->new(raw => $payload);
}
}
if ($next) {
$next->unpack;
$self->lsa($next);
$payload = $next->payload;
}
$self->payload($payload);
$self;
}
sub print {
my $self = shift;
my $l = $self->layer;
my $buf = sprintf
"$l: lsAge:%d options:0x%02x lsType:0x%02x linkStateId:%s\n".
"$l: advertisingRouter:%s lsSequenceNumber:0x%08x\n".
"$l: lsChecksum:0x%04x length:%d",
$self->lsAge,
$self->options,
$self->lsType,
$self->linkStateId,
$self->advertisingRouter,
$self->lsSequenceNumber,
$self->lsChecksum,
$self->length,
;
if ($self->lsa) {
$buf .= "\n".$self->lsa->print;
}
$buf;
}
1;
__END__
=head1 NAME
Net::Frame::Layer::OSPF::Lsa - OSPF Lsa type object
=head1 SYNOPSIS
use Net::Frame::Layer::OSPF qw(:consts);
use Net::Frame::Layer::OSPF::Lsa;
use Net::Frame::Layer::OSPF::Lsa::Router;
# Build a LSA-Router
my $lsa = Net::Frame::Layer::OSPF::Lsa->new(
lsAge => 30,
options => 0,
lsType => NF_OSPF_LSTYPE_ROUTER,
linkStateId => '0.0.0.0',
advertisingRouter => '0.0.0.0',
lsSequenceNumber => 0,
lsChecksum => 0,
length => NF_OSPF_LSA_HDR_LEN,
full => 1,
);
my $router = Net::Frame::Layer::OSPF::Lsa::Router->new(
flags => 0,
zero => 0,
nLink => 1,
linkId => $ip,
linkData => $netmask,
type => 0x03,
nTos => 0,
metric => 10,
);
$lsa->lsa($router);
$lsa->computeLengths;
$lsa->computeChecksums;
print $lsa->print."\n";
=head1 DESCRIPTION
This modules implements the encoding and decoding of the OSPF Lsa object.
See also B<Net::Frame::Layer> for other attributes and methods.
=head1 ATTRIBUTES
=over 4
=item B<lsAge>
=item B<options>
=item B<lsType>
=item B<linkStateId>
=item B<advertisingRouter>
=item B<lsSequenceNumber>
=item B<lsChecksum>
=item B<length>
=item B<lsa>
=item B<full>
=back
The following are inherited attributes. See B<Net::Frame::Layer> for more information.
=over 4
=item B<raw>
=item B<payload>
=item B<nextLayer>
=back
=head1 METHODS
=over 4
=item B<new>
=item B<new> (hash)
Object constructor. You can pass attributes that will overwrite default ones. See B<SYNOPSIS> for default values.
=back
The following are inherited methods. Some of them may be overriden in this layer, and some others may not be meaningful in this layer. See B<Net::Frame::Layer> for more information.
=over 4
=item B<layer>
=item B<computeLengths>
=item B<computeChecksums>
=item B<pack>
=item B<unpack>
=item B<encapsulate>
=item B<getLength>
=item B<getPayloadLength>
=item B<print>
=item B<dump>
=back
=head1 CONSTANTS
No constants here.
=head1 SEE ALSO
L<Net::Frame::Layer::OSPF>, L<Net::Frame::Layer>
=head1 AUTHOR
Patrice E<lt>GomoRE<gt> Auffret
=head1 COPYRIGHT AND LICENSE
Copyright (c) 2006-2007, Patrice E<lt>GomoRE<gt> Auffret
You may distribute this module under the terms of the Artistic license.
See LICENSE.Artistic file in the source distribution archive.
=cut