#
# $Id: ICMPv4.pm,v 1.3.2.9 2006/11/12 20:28:34 gomor Exp $
#
package Net::Packet::ICMPv4;
use strict;
use warnings;
use Carp;
require Net::Packet::Layer4;
our @ISA = qw(Net::Packet::Layer4);
use Net::Packet::Env qw($Env);
use Net::Packet::Utils qw(getRandom16bitsInt getRandom32bitsInt inetChecksum
inetAton inetNtoa);
use Net::Packet::Consts qw(:icmpv4 :layer);
require Net::Packet::IPv4;
require Net::Packet::Frame;
our @AS = qw(
type
code
checksum
identifier
sequenceNumber
originateTimestamp
receiveTimestamp
transmitTimestamp
addressMask
gateway
unused
error
data
);
__PACKAGE__->cgBuildIndices;
__PACKAGE__->cgBuildAccessorsScalar(\@AS);
no strict 'vars';
sub new {
shift->SUPER::new(
type => NP_ICMPv4_TYPE_ECHO_REQUEST,
code => NP_ICMPv4_CODE_ZERO,
checksum => 0,
identifier => getRandom16bitsInt(),
sequenceNumber => getRandom16bitsInt(),
originateTimestamp => time(),
receiveTimestamp => 0,
transmitTimestamp => 0,
addressMask => 0,
gateway => '127.0.0.1',
unused => 0,
data => '',
@_,
);
}
sub getKey { 'ICMP' }
sub getKeyReverse { 'ICMP' }
sub recv {
my $self = shift;
my ($frame) = @_;
my $env = $frame->env;
for ($env->dump->frames) {
next unless $_->timestamp ge $frame->timestamp;
if ($frame->l3) {
if ($_->isIcmpv4 && $_->l3->src eq $frame->l3->dst) {
if ($self->[$__type] == NP_ICMPv4_TYPE_ECHO_REQUEST
&& $_->l4->type == NP_ICMPv4_TYPE_ECHO_REPLY) {
return $_;
}
elsif ($self->[$__type] == NP_ICMPv4_TYPE_TIMESTAMP_REQUEST
&& $_->l4->type == NP_ICMPv4_TYPE_TIMESTAMP_REPLY) {
return $_;
}
elsif ($self->[$__type] == NP_ICMPv4_TYPE_INFORMATION_REQUEST
&& $_->l4->type == NP_ICMPv4_TYPE_INFORMATION_REPLY) {
return $_;
}
elsif ($self->[$__type] == NP_ICMPv4_TYPE_ADDRESS_MASK_REQUEST
&& $_->l4->type == NP_ICMPv4_TYPE_ADDRESS_MASK_REPLY) {
return $_;
}
}
}
# DescL4 recv, warning, it may receive a packet targetted at another
# host, since no L3 headers is kept at D4 for packet matching
else {
if ($self->[$__type] == NP_ICMPv4_TYPE_ECHO_REQUEST
&& $_->l4->type == NP_ICMPv4_TYPE_ECHO_REPLY) {
return $_;
}
elsif ($self->[$__type] == NP_ICMPv4_TYPE_TIMESTAMP_REQUEST
&& $_->l4->type == NP_ICMPv4_TYPE_TIMESTAMP_REPLY) {
return $_;
}
elsif ($self->[$__type] == NP_ICMPv4_TYPE_INFORMATION_REQUEST
&& $_->l4->type == NP_ICMPv4_TYPE_INFORMATION_REPLY) {
return $_;
}
elsif ($self->[$__type] == NP_ICMPv4_TYPE_ADDRESS_MASK_REQUEST
&& $_->l4->type == NP_ICMPv4_TYPE_ADDRESS_MASK_REPLY) {
return $_;
}
}
}
undef;
}
my $packTypes = {
NP_ICMPv4_TYPE_ECHO_REQUEST() => \&_packEcho,
NP_ICMPv4_TYPE_ECHO_REPLY() => \&_packEcho,
NP_ICMPv4_TYPE_TIMESTAMP_REQUEST() => \&_packTimestamp,
NP_ICMPv4_TYPE_TIMESTAMP_REPLY() => \&_packTimestamp,
NP_ICMPv4_TYPE_INFORMATION_REQUEST() => \&_packInformation,
NP_ICMPv4_TYPE_INFORMATION_REPLY() => \&_packInformation,
NP_ICMPv4_TYPE_ADDRESS_MASK_REQUEST() => \&_packAddressMask,
NP_ICMPv4_TYPE_ADDRESS_MASK_REPLY() => \&_packAddressMask,
NP_ICMPv4_TYPE_DESTINATION_UNREACHABLE() => \&_packDestUnreach,
NP_ICMPv4_TYPE_REDIRECT() => \&_packRedirect,
NP_ICMPv4_TYPE_TIME_EXCEEDED() => \&_packTimeExceed,
};
my $unpackTypes = {
NP_ICMPv4_TYPE_ECHO_REQUEST() => \&_unpackEcho,
NP_ICMPv4_TYPE_ECHO_REPLY() => \&_unpackEcho,
NP_ICMPv4_TYPE_TIMESTAMP_REQUEST() => \&_unpackTimestamp,
NP_ICMPv4_TYPE_TIMESTAMP_REPLY() => \&_unpackTimestamp,
NP_ICMPv4_TYPE_INFORMATION_REQUEST() => \&_unpackInformation,
NP_ICMPv4_TYPE_INFORMATION_REPLY() => \&_unpackInformation,
NP_ICMPv4_TYPE_ADDRESS_MASK_REQUEST() => \&_unpackAddressMask,
NP_ICMPv4_TYPE_ADDRESS_MASK_REPLY() => \&_unpackAddressMask,
NP_ICMPv4_TYPE_DESTINATION_UNREACHABLE() => \&_unpackDestUnreach,
NP_ICMPv4_TYPE_REDIRECT() => \&_unpackRedirect,
NP_ICMPv4_TYPE_TIME_EXCEEDED() => \&_unpackTimeExceed,
};
sub getDataLength {
my $self = shift;
my $data = $self->[$__data];
$data ? length($data) : 0;
}
sub getLength {
my $self = shift;
my $dataLength = $self->getDataLength;
my $hdrLengths = {
NP_ICMPv4_TYPE_ECHO_REQUEST() => 8 + $dataLength,
NP_ICMPv4_TYPE_ECHO_REPLY() => 8 + $dataLength,
NP_ICMPv4_TYPE_TIMESTAMP_REQUEST() => 20 + $dataLength,
NP_ICMPv4_TYPE_TIMESTAMP_REPLY() => 20 + $dataLength,
NP_ICMPv4_TYPE_INFORMATION_REQUEST() => 8 + $dataLength,
NP_ICMPv4_TYPE_INFORMATION_REPLY() => 8 + $dataLength,
NP_ICMPv4_TYPE_ADDRESS_MASK_REQUEST() => 12 + $dataLength,
NP_ICMPv4_TYPE_ADDRESS_MASK_REPLY() => 12 + $dataLength,
NP_ICMPv4_TYPE_DESTINATION_UNREACHABLE() => 8 + $dataLength,
NP_ICMPv4_TYPE_REDIRECT() => 8 + $dataLength,
NP_ICMPv4_TYPE_TIME_EXCEEDED() => 8 + $dataLength,
};
$hdrLengths->{$self->[$__type]} || 0;
}
sub _handleType {
my $self = shift;
my ($format, $fields, $values) = @_;
if (@$values) {
return($self->SUPER::pack($format, @$values) || undef);
}
else {
my @elts = $self->SUPER::unpack($format, $self->[$__payload])
or return undef;
my $n = 0;
return { map { $_ => $elts[$n++] } @$fields };
}
}
sub _packEcho {
my $self = shift;
$self->_handleType(
'nn', [], [ $self->[$__identifier], $self->[$__sequenceNumber] ]
);
}
sub _unpackEcho {
shift->_handleType('nn a*', [ qw(identifier sequenceNumber data) ], []);
}
sub _packTimestamp {
my $self = shift;
$self->_handleType('nnNNN', [],
[ $self->[$__identifier], $self->[$__sequenceNumber],
$self->[$__originateTimestamp], $self->[$__receiveTimestamp],
$self->[$__transmitTimestamp]
],
);
}
sub _unpackTimestamp {
shift->_handleType(
'nnNNN a*',
[ qw(identifier sequenceNumber originateTimestamp receiveTimestamp
transmitTimestamp data) ],
[],
);
}
# It has same fields as ICMP echo
sub _packInformation { shift->_packEcho }
sub _unpackInformation { shift->_unpackEcho }
sub _packAddressMask {
my $self = shift;
$self->_handleType('nnN', [],
[ $self->[$__identifier], $self->[$__sequenceNumber],
$self->[$__addressMask]
],
);
}
sub _unpackAddressMask {
shift->_handleType(
'nnN a*',
[ qw(identifier sequenceNumber addressMask data) ],
[],
);
}
# Pad ICMP error returned to achieve IP length (from IP request),
# and put it as a Frame into error instance data
sub _dataToFrame {
my $self = shift;
my ($data) = @_;
# Keep old behaviour for backward compat
if (! $Env->doFrameReturnList) {
my $ip = Net::Packet::IPv4->new(raw => $data);
$data .= "\x00" x $ip->length;
my $f = Net::Packet::Frame->new(
raw => $data, encapsulate => NP_LAYER_IPv4
) or return undef;
return $f;
}
else {
$self->[$__payload] = $data;
}
undef;
}
sub _packDestUnreach {
my $self = shift;
$self->_handleType(
'N',
[],
[ $self->[$__unused] ],
);
}
sub _unpackDestUnreach {
my $self = shift;
my $href = $self->_handleType(
'N a*',
[ qw(unused data) ],
[],
);
$href->{error} = $self->_dataToFrame($href->{data}) if $href->{data};
$href;
}
sub _packRedirect {
my $self = shift;
$self->_handleType(
'a4',
[],
[ inetAton($self->[$__gateway]) ],
);
}
sub _unpackRedirect {
my $self = shift;
my $href = $self->_handleType(
'a4 a*',
[ qw(gateway data) ],
[],
);
$href->{gateway} = inetNtoa($href->{gateway});
$href->{error} = $self->_dataToFrame($href->{data}) if $href->{data};
$href;
}
sub _packTimeExceed {
my $self = shift;
$self->_handleType(
'N',
[],
[ $self->unused ],
);
}
sub _unpackTimeExceed {
my $self = shift;
my $href = $self->_handleType(
'N a*',
[ qw(unused data) ],
[],
);
$href->{error} = $self->_dataToFrame($href->{data}) if $href->{data};
$href;
}
sub _decodeError {
my $self = shift;
carp("@{[(caller(0))[3]]}: unknown ICMPv4: ".
"type: @{[$self->type]}, code: @{[$self->code]}\n");
undef;
}
sub pack {
my $self = shift;
# Keep old behaviour for backward compat
if (! $Env->doFrameReturnList) {
my $error = $self->[$__error];
$self->[$__data] = $error->raw if $error;
}
$self->[$__raw] = $self->SUPER::pack('CCn',
$self->[$__type],
$self->[$__code],
$self->[$__checksum],
) or return undef;
my $sub = $packTypes->{$self->[$__type]} || \&_decodeError;
my $raw = $self->$sub or return undef;
if ($self->[$__data]) {
$raw .= $self->SUPER::pack('a*', $self->[$__data])
or return undef;
}
$self->[$__raw] = $self->[$__raw].$raw;
1;
}
sub unpack {
my $self = shift;
my ($type, $code, $checksum, $payload) =
$self->SUPER::unpack('CCS a*', $self->[$__raw])
or return undef;
$self->[$__type] = $type;
$self->[$__code] = $code;
$self->[$__checksum] = $checksum;
$self->[$__payload] = $payload;
# unpack specific ICMPv4 types
my $sub = $unpackTypes->{$self->[$__type]} || \&_decodeError;
my $href = $self->$sub or return undef;
$self->$_($href->{$_}) for keys %$href;
# Keep old behaviour for backward compat
if (! $Env->doFrameReturnList) {
# payload has been handled by previous chunk of code
$self->[$__payload] = undef;
}
1;
}
sub computeChecksums {
my $self = shift;
my $sub = $packTypes->{$self->[$__type]} || \&_decodeError;
my $raw = $self->$sub or return undef;
if (my $data = $self->[$__data]) {
$raw .= $self->SUPER::pack('a*', $data)
or return undef;
}
my $packed = $self->SUPER::pack('CCn', $self->[$__type], $self->[$__code], 0)
or return undef;
$self->[$__checksum] = inetChecksum($packed.$raw);
1;
}
sub encapsulate {
# Keep old behaviour for backward compat
if (! $Env->doFrameReturnList) {
return NP_LAYER_NONE;
}
my $types = {
NP_ICMPv4_TYPE_ECHO_REQUEST() => NP_LAYER_NONE(),
NP_ICMPv4_TYPE_ECHO_REPLY() => NP_LAYER_NONE(),
NP_ICMPv4_TYPE_TIMESTAMP_REQUEST() => NP_LAYER_NONE(),
NP_ICMPv4_TYPE_TIMESTAMP_REPLY() => NP_LAYER_NONE(),
NP_ICMPv4_TYPE_INFORMATION_REQUEST() => NP_LAYER_NONE(),
NP_ICMPv4_TYPE_INFORMATION_REPLY() => NP_LAYER_NONE(),
NP_ICMPv4_TYPE_ADDRESS_MASK_REQUEST() => NP_LAYER_NONE(),
NP_ICMPv4_TYPE_ADDRESS_MASK_REPLY() => NP_LAYER_NONE(),
NP_ICMPv4_TYPE_DESTINATION_UNREACHABLE() => NP_LAYER_IPv4(),
NP_ICMPv4_TYPE_REDIRECT() => NP_LAYER_IPv4(),
NP_ICMPv4_TYPE_TIME_EXCEEDED() => NP_LAYER_IPv4(),
};
$types->{shift->type} || NP_LAYER_UNKNOWN();
}
sub print {
my $self = shift;
my $i = $self->is;
my $l = $self->layer;
my $buf = sprintf
"$l:+$i: type:%d code:%d checksum:0x%04x headerLength:%d",
$self->[$__type], $self->[$__code], $self->[$__checksum],
$self->getLength;
if ($self->data) {
$buf .= sprintf("\n$l: $i: dataLength:%d data:%s",
$self->getDataLength,
$self->SUPER::unpack('H*', $self->data))
or return undef;
}
$buf;
}
#
# Helpers
#
sub _isType { shift->[$__type] == shift() }
sub isTypeEchoRequest { shift->_isType(NP_ICMPv4_TYPE_ECHO_REQUEST) }
sub isTypeEchoReply { shift->_isType(NP_ICMPv4_TYPE_ECHO_REPLY) }
sub isTypeTimestampRequest {
shift->_isType(NP_ICMPv4_TYPE_TIMESTAMP_REQUEST);
}
sub isTypeTimestampReply {
shift->_isType(NP_ICMPv4_TYPE_TIMESTAMP_REPLY);
}
sub isTypeInformationRequest {
shift->_isType(NP_ICMPv4_TYPE_INFORMATION_REQUEST);
}
sub isTypeInformationReply {
shift->_isType(NP_ICMPv4_TYPE_INFORMATION_REPLY);
}
sub isTypeAddressMaskRequest {
shift->_isType(NP_ICMPv4_TYPE_ADDRESS_MASK_REQUEST);
}
sub isTypeAddressMaskReply {
shift->_isType(NP_ICMPv4_TYPE_ADDRESS_MASK_REPLY);
}
sub isTypeDestinationUnreachable {
shift->_isType(NP_ICMPv4_TYPE_DESTINATION_UNREACHABLE);
}
1;
__END__
=head1 NAME
Net::Packet::ICMPv4 - Internet Control Message Protocol v4 layer 4 object
=head1 SYNOPSIS
use Net::Packet::Consts qw(:icmpv4);
require Net::Packet::ICMPv4;
# Build echo-request header
my $echo = Net::Packet::ICMPv4->new(data => '0123456789');
# Build information-request header
my $info = Net::Packet::ICMPv4->new(
type => NP_ICMPv4_TYPE_INFORMATION_REQUEST,
data => '0123456789',
);
# Build address-mask request header
my $mask = Net::Packet::ICMPv4->new(
type => NP_ICMPv4_TYPE_ADDRESS_MASK_REQUEST,
data => '0123456789',
);
# Build timestamp request header
my $timestamp = Net::Packet::ICMPv4->new(
type => NP_ICMPv4_TYPE_TIMESTAMP_REQUEST,
data => '0123456789',
);
$timestamp->pack;
print 'RAW: '.unpack('H*', $timestamp->raw)."\n";
# Read a raw layer
my $layer = Net::Packet::ICMPv4->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 ICMPv4 layer.
RFC: ftp://ftp.rfc-editor.org/in-notes/rfc792.txt
See also B<Net::Packet::Layer> and B<Net::Packet::Layer4> for other attributes a
nd methods.
=head1 ATTRIBUTES
=over 4
=item B<type>
=item B<code>
Type and code fields. See B<CONSTANTS>.
=item B<checksum>
The checksum of ICMPv4 header.
=item B<identifier>
Identification number.
=item B<sequenceNumber>
Sequence number.
=item B<originateTimestamp>
=item B<receiveTimestamp>
=item B<transmitTimestamp>
Three timestamps used by the B<NP_ICMPv4_TYPE_TIMESTAMP_REQUEST> message.
=item B<addressMask>
Used by the B<NP_ICMPv4_TYPE_ADDRESS_MASK_REQUEST> message.
=item B<gateway>
Used by the B<NP_ICMPv4_TYPE_REDIRECT> message.
=item B<unused>
Zero value field used in various ICMP messages.
=item B<error>
A pointer to a B<Net::Packet::Frame> object, usually set when an ICMP error message has been returned.
=item B<data>
Additionnal data can be added to an ICMP message, traditionnaly used in B<NP_ICMPv4_TYPE_ECHO_REQUEST>.
=back
=head1 METHODS
=over 4
=item B<new>
Object constructor. You can pass attributes that will overwrite default ones. Default values:
type: NP_ICMPv4_TYPE_ECHO_REQUEST
code: NP_ICMPv4_CODE_ZERO
checksum: 0
identifier: getRandom16bitsInt()
sequenceNumber: getRandom16bitsInt()
originateTimestamp: time()
receiveTimestamp: 0
transmitTimestamp: 0
addressMask: 0
gateway: "127.0.0.1"
unused: 0
data: ""
=item B<recv>
Will search for a matching replies in B<framesSorted> or B<frames> from a B<Net::Packet::Dump> object.
=item B<getDataLength>
Returns the length in bytes of B<data> attribute.
=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<isTypeEchoRequest>
=item B<isTypeEchoReply>
=item B<isTypeTimestampRequest>
=item B<isTypeTimestampReply>
=item B<isTypeInformationRequest>
=item B<isTypeInformationReply>
=item B<isTypeAddressMaskRequest>
=item B<isTypeAddressMaskReply>
=item B<isTypeDestinationUnreachable>
Returns 1 if the B<type> attribute is of specified type.
=back
=head1 CONSTANTS
Load them: use Net::Packet::Consts qw(:icmpv4);
=over 4
=item B<NP_ICMPv4_CODE_ZERO>
ICMP code zero, used by various ICMP messages.
=item B<NP_ICMPv4_TYPE_DESTINATION_UNREACHABLE>
=item B<NP_ICMPv4_CODE_NETWORK>
=item B<NP_ICMPv4_CODE_HOST>
=item B<NP_ICMPv4_CODE_PROTOCOL>
=item B<NP_ICMPv4_CODE_PORT>
=item B<NP_ICMPv4_CODE_FRAGMENTATION_NEEDED>
=item B<NP_ICMPv4_CODE_SOURCE_ROUTE_FAILED>
Destination unreachable type, with possible code numbers.
=item B<NP_ICMPv4_TYPE_REDIRECT>
=item B<NP_ICMPv4_CODE_FOR_NETWORK>
=item B<NP_ICMPv4_CODE_FOR_HOST>
=item B<NP_ICMPv4_CODE_FOR_TOS_AND_NETWORK>
=item B<NP_ICMPv4_CODE_FOR_TOS_AND_HOST>
Redirect type message, with possible code numbers.
=item B<NP_ICMPv4_TYPE_TIME_EXCEEDED>
=item B<NP_ICMPv4_CODE_TTL_IN_TRANSIT>
=item B<NP_ICMPv4_CODE_FRAGMENT_REASSEMBLY>
Time exceeded message, with possible code numbers.
=item B<NP_ICMPv4_TYPE_ECHO_REQUEST>
=item B<NP_ICMPv4_TYPE_ECHO_REPLY>
=item B<NP_ICMPv4_TYPE_TIMESTAMP_REQUEST>
=item B<NP_ICMPv4_TYPE_TIMESTAMP_REPLY>
=item B<NP_ICMPv4_TYPE_INFORMATION_REQUEST>
=item B<NP_ICMPv4_TYPE_INFORMATION_REPLY>
=item B<NP_ICMPv4_TYPE_ADDRESS_MASK_REQUEST>
=item B<NP_ICMPv4_TYPE_ADDRESS_MASK_REPLY>
Other request/reply ICMP messages types.
=back
=head1 AUTHOR
Patrice E<lt>GomoRE<gt> Auffret
=head1 COPYRIGHT AND LICENSE
Copyright (c) 2004-2006, 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
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