#
# $Id: ARP.pm 1640 2009-11-09 17:58:27Z gomor $
#
package Net::Packet::ARP;
use strict;
use warnings;
require Net::Packet::Layer3;
our @ISA = qw(Net::Packet::Layer3);
our @AS = qw(
hType
pType
hSize
pSize
opCode
src
srcIp
dst
dstIp
);
__PACKAGE__->cgBuildIndices;
__PACKAGE__->cgBuildAccessorsScalar(\@AS);
no strict 'vars';
use Net::Packet::Env qw($Env);
use Net::Packet::Utils qw(convertMac inetAton inetNtoa);
use Net::Packet::Consts qw(:arp :layer);
sub new {
my $self = shift->SUPER::new(
hType => NP_ARP_HTYPE_ETH,
pType => NP_ARP_PTYPE_IPv4,
hSize => NP_ARP_HSIZE_ETH,
pSize => NP_ARP_PSIZE_IPv4,
opCode => NP_ARP_OPCODE_REQUEST,
src => $Env->mac,
dst => NP_ARP_ADDR_BROADCAST,
srcIp => $Env->ip,
dstIp => "127.0.0.1",
@_,
);
$self->[$__src] = lc($self->[$__src]) if $self->[$__src];
$self->[$__dst] = lc($self->[$__dst]) if $self->[$__dst];
$self;
}
sub getLength { NP_ARP_HDR_LEN }
sub pack {
my $self = shift;
(my $srcMac = $self->[$__src]) =~ s/://g;
(my $dstMac = $self->[$__dst]) =~ s/://g;
$self->[$__raw] = $self->SUPER::pack('nnUUnH12a4H12a4',
$self->[$__hType],
$self->[$__pType],
$self->[$__hSize],
$self->[$__pSize],
$self->[$__opCode],
$srcMac,
inetAton($self->[$__srcIp]),
$dstMac,
inetAton($self->[$__dstIp]),
) or return undef;
1;
}
sub unpack {
my $self = shift;
my ($hType, $pType, $hSize, $pSize, $opCode, $srcMac, $srcIp, $dstMac,
$dstIp) = $self->SUPER::unpack('nnUUnH12a4H12a4', $self->[$__raw])
or return undef;
$self->[$__hType] = $hType;
$self->[$__pType] = $pType;
$self->[$__hSize] = $hSize;
$self->[$__pSize] = $pSize;
$self->[$__opCode] = $opCode;
$self->[$__src] = convertMac($srcMac);
$self->[$__srcIp] = inetNtoa($srcIp);
$self->[$__dst] = convertMac($dstMac);
$self->[$__dstIp] = inetNtoa($dstIp);
1;
}
sub recv {
my $self = shift;
my ($frame) = @_;
my $src = $self->[$__src];
my $srcIp = $self->[$__srcIp];
my $dstIp = $self->[$__dstIp];
my $opCode = $self->[$__opCode];
for ($frame->env->dump->framesFor($frame)) {
if ($opCode == NP_ARP_OPCODE_REQUEST) {
if ($_->l3->opCode == NP_ARP_OPCODE_REPLY
&& $_->l3->dst eq $src
&& $_->l3->srcIp eq $dstIp
&& $_->l3->dstIp eq $srcIp) {
return $_ if $_->timestamp ge $frame->timestamp;
}
}
}
undef;
}
sub encapsulate { NP_LAYER_NONE }
sub print {
my $self = shift;
my $l = $self->layer;
my $i = $self->is;
sprintf
"$l:+$i: hType:0x%04x pType:0x%04x hSize:0x%02x pSize:0x%02x".
" opCode:0x%04x\n".
"$l: $i: src:%s srcIp:%s\n".
"$l: $i: dst:%s dstIp:%s",
$self->[$__hType], $self->[$__pType], $self->[$__hSize],
$self->[$__pSize], $self->[$__opCode], $self->[$__src],
$self->[$__srcIp], $self->[$__dst], $self->[$__dstIp];
}
#
# Helpers
#
sub _isOpCode { shift->[$__opCode] == shift }
sub isRequest { shift->_isOpCode(NP_ARP_OPCODE_REQUEST) }
sub isReply { shift->_isOpCode(NP_ARP_OPCODE_REPLY) }
1;
__END__
=head1 NAME
Net::Packet::ARP - Address Resolution Protocol layer 3 object
=head1 SYNOPSIS
use Net::Packet::Consts qw(:arp);
require Net::Packet::ARP;
# Build a layer
my $layer = Net::Packet::ARP->new(
dstIp => "192.168.0.1",
);
$layer->pack;
print 'RAW: '.unpack('H*', $layer->raw)."\n";
# Read a raw layer
my $layer = Net::Packet::ARP->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 ARP layer.
RFC: ftp://ftp.rfc-editor.org/in-notes/rfc826.txt
See also B<Net::Packet::Layer> and B<Net::Packet::Layer3> for other attributes and methods.
=head1 ATTRIBUTES
=over 4
=item B<hType>
=item B<pType>
Hardware and protocol address types.
=item B<hSize>
=item B<pSize>
Hardware and protocol address sizes in bytes.
=item B<opCode>
The operation code number to perform.
=item B<src>
=item B<dst>
Source and destination hardware addresses.
=item B<srcIp>
=item B<dstIp>
Source and destination IP addresses.
=back
=head1 METHODS
=over 4
=item B<new>
Object constructor. You can pass attributes that will overwrite default ones. Default values:
hType: NP_ARP_HTYPE_ETH
pType: NP_ARP_PTYPE_IPv4
hSize: NP_ARP_HSIZE_ETH
pSize: NP_ARP_PSIZE_IPv4
opCode: NP_ARP_OPCODE_REQUEST
src: $Env->mac
dst: NP_ARP_ADDR_BROADCAST
srcIp: $Env->ip
dstIp: 127.0.0.1
=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.
=item B<recv>
Will search for a matching replies in B<framesSorted> or B<frames> from a B<Net::Packet::Dump> object.
=item B<isRequest>
=item B<isReply>
Returns 1 if the B<opCode> attribute is of specified type.
=back
=head1 CONSTANTS
Load them: use Net::Packet::Consts qw(:arp);
=over 4
=item B<NP_ARP_HTYPE_ETH>
=item B<NP_ARP_PTYPE_IPv4>
Hardware and protocol address types.
=item B<NP_ARP_HSIZE_ETH>
=item B<NP_ARP_PSIZE_IPv4>
Hardware and protocol address sizes.
=item B<NP_ARP_OPCODE_REQUEST>
=item B<NP_ARP_OPCODE_REPLY>
Operation code numbers.
=item B<NP_ARP_ADDR_BROADCAST>
Broadcast address for B<src> or B<dst> attributes.
=back
=head1 AUTHOR
Patrice E<lt>GomoRE<gt> Auffret
=head1 COPYRIGHT AND LICENSE
Copyright (c) 2004-2009, 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