#
# $Id: LLC.pm 2002 2015-02-15 16:50:35Z gomor $
#
package Net::Packet::LLC;
use strict;
use warnings;
require Net::Packet::Layer3;
our @ISA = qw(Net::Packet::Layer3);
use Net::Packet::Consts qw(:llc :layer);
require Bit::Vector;
our @AS = qw(
dsap
ig
ssap
cr
control
oui
pid
);
__PACKAGE__->cgBuildIndices;
__PACKAGE__->cgBuildAccessorsScalar(\@AS);
no strict 'vars';
sub new {
shift->SUPER::new(
dsap => NP_LLC_DSAP_SNAP,
ig => 1,
ssap => NP_LLC_SSAP_SNAP,
cr => 1,
control => 0x03,
oui => NP_LLC_OUI_CISCO,
pid => NP_LLC_PID_CDP,
@_,
);
}
sub getLength { NP_LLC_HDR_LEN }
sub pack {
my $self = shift;
my $dsap = Bit::Vector->new_Dec(7, $self->[$__dsap]);
my $ig = Bit::Vector->new_Dec(1, $self->[$__ig]);
my $ssap = Bit::Vector->new_Dec(7, $self->[$__ssap]);
my $cr = Bit::Vector->new_Dec(1, $self->[$__cr]);
my $v16 = $dsap->Concat_List($ig, $ssap, $cr);
my $oui = Bit::Vector->new_Dec(24, $self->[$__oui]);
$self->[$__raw] = $self->SUPER::pack('nCB24n',
$v16->to_Dec,
$self->[$__control],
$oui->to_Bin,
$self->[$__pid],
) or return undef;
1;
}
sub unpack {
my $self = shift;
my ($dsapIgSsapCr, $control, $oui, $pid, $payload) =
$self->SUPER::unpack('nCB24n a*', $self->[$__raw])
or return undef;
my $v16 = Bit::Vector->new_Dec(16, $dsapIgSsapCr);
$self->[$__dsap] = $v16->Chunk_Read(7, 0);
$self->[$__ig] = $v16->Chunk_Read(1, 7);
$self->[$__ssap] = $v16->Chunk_Read(7, 8);
$self->[$__cr] = $v16->Chunk_Read(1, 15);
$self->[$__control] = $control;
my $v24 = Bit::Vector->new_Bin(24, $oui);
$self->[$__oui] = $v24->to_Dec;
$self->[$__pid] = $pid;
$self->[$__payload] = $payload;
1;
}
sub encapsulate {
my $types = {
NP_LLC_PID_CDP() => NP_LAYER_CDP(),
NP_LLC_PID_STP() => NP_LAYER_STP(),
};
$types->{shift->[$__pid]} || NP_LAYER_UNKNOWN();
}
sub print {
my $self = shift;
my $l = $self->layer;
my $i = $self->is;
sprintf "$l:+$i: dsap:0x%02x ig:%d ssap:0x%02x cr:%d control:0x%02x\n".
"$l: $i: oui:0x%06x pid:0x%04x",
$self->[$__dsap], $self->[$__ig], $self->[$__ssap], $self->[$__cr],
$self->[$__control], $self->[$__oui], $self->[$__pid];
}
1;
__END__
=head1 NAME
Net::Packet::LLC - Logical-Link Control layer 3 object
=head1 SYNOPSIS
use Net::Packet::Consts qw(:llc);
require Net::Packet::LLC;
# Build a layer
my $layer = Net::Packet::LLC->new(
dsap => NP_LLC_DSAP_SNAP,
ig => 1,
ssap => NP_LLC_SSAP_SNAP,
cr => 1,
control => 0x03,
oui => NP_LLC_OUI_CISCO,
pid => NP_LLC_PID_CDP,
);
$layer->pack;
print 'RAW: '.unpack('H*', $layer->raw)."\n";
# Read a raw layer
my $layer = Net::Packet::LLC->new(raw => $raw);
print $layer->print."\n";
print 'PAYLOAD: '.unpack('H*', $layer->payload)."\n"
if $layer->payload;
=head1 DESCRIPTION
This modules implements the encoding and decoding of the Logical-Link Control layer.
See also B<Net::Packet::Layer> and B<Net::Packet::Layer3> for other attributes and methods.
=head1 ATTRIBUTES
=over 4
=item B<dsap> - 7 bits
=item B<ig> - 1 bit
=item B<ssap> - 7 bits
=item B<cr> - 1 bit
=item B<control> - 8 bits
=item B<oui> - 24 bits
=item B<pid> - 16 bits
=back
=head1 METHODS
=over 4
=item B<new>
Object constructor. You can pass attributes that will overwrite default ones. Default values:
dsap: NP_LLC_DSAP_SNAP
ig: 1
ssap: NP_LLC_SSAP_SNAP
cr: 1
control: 0x03
oui: NP_LLC_OUI_CISCO
pid: NP_LLC_PID_CDP
=item B<pack>
Packs all attributes into a raw format, in order to inject to network. Returns 1 on success, undef otherwise.
=item B<unpack>
Unpacks raw data from network and stores attributes into the object. Returns 1 on success, undef otherwise.
=back
=head1 CONSTANTS
Load them: use Net::Packet::Consts qw(:llc);
=over 4
=item B<NP_LLC_HDR_LEN>
LLC header length.
=item B<NP_LLC_OUI_CISCO>
Oui attribute constants.
=item B<NP_LLC_PID_CDP>
=item B<NP_LLC_PID_STP>
Pid attribute constants.
=item B<NP_LLC_DSAP_SNAP>
Dsap attribute constants.
=item B<NP_LLC_SSAP_SNAP>
Ssap attribute constants.
=back
=head1 AUTHOR
Patrice E<lt>GomoRE<gt> Auffret
=head1 COPYRIGHT AND LICENSE
Copyright (c) 2004-2015, 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.
=head1 RELATED MODULES
L<NetPacket>, L<Net::RawIP>, L<Net::RawSock>
=cut