NAME

Net::Packet - a framework to easily send and receive frames from layer 2 to layer 7

SYNOPSIS

# Load all modules, it also initializes a Net::Packet::Env object, 
# and imports all utility subs and constants in current namespace
# WARNING: this is not the prefered way to use Net::Packet
use Net::Packet;

# Build IPv4 header
my $ip = Net::Packet::IPv4->new(dst => '192.168.0.1');

# Build TCP header
my $tcp = Net::Packet::TCP->new(dst => 22);

# Assamble frame, it will also open a Net::Packet::DescL3 descriptor
# and a Net::Packet::Dump object
my $frame = Net::Packet::Frame->new(l3 => $ip, l4 => $tcp);

$frame->send;

# Print the reply just when it has been received
until ($Env->dump->timeout) {
   if ($frame->recv) {
      print $frame->reply->l3, "\n";
      print $frame->reply->l4, "\n";
      last;
   }
}

# Alternative way of using Net::Packet, which is the recommanded way
# First thing to do, get a default Env object. It will contain all 
# information regarding your default interface setup and some 
# specific options regarding Net::Packet framework behaviour
use Net::Packet::Env qw($Env);

# Then, load modules you need to accomplish your work
require Net::Packet::DescL3;
require Net::Packet::Dump;
require Net::Packet::Frame;
require Net::Packet::IPv4;
require Net::Packet::TCP;

# We manually create Desc and Dump objects to have complete control 
# on Net::Packet framework behaviour
my $desc = Net::Packet::DescL3->new(
   target => '192.168.0.1',
);

my $dump = Net::Packet::Dump->new(
   filter        => 'tcp',
   keepTimestamp => 1,
);
$dump->start;

# Build IPv4 header
my $ip = Net::Packet::IPv4->new(dst => '192.168.0.1');

# Build TCP header
my $tcp = Net::Packet::TCP->new(dst => 22);

# Assamble frame. Because we have created Desc and Dump objects, 
# they will not be automatically created here
my $frame = Net::Packet::Frame->new(l3 => $ip, l4 => $tcp);
$frame->send;

until ($dump->timeout) {
   if ($frame->recv) {
      print $frame->reply->l3, "\n";
      print $frame->reply->l4, "\n";
      last;
   }
}

$dump->stop;
$dump->clean;

CLASS HIERARCHY

Net::Packet

Net::Packet::Env

Net::Packet::Dump

Net::Packet::Utils

Net::Packet::Desc
   |
   +---Net::Packet::DescL2
   |
   +---Net::Packet::DescL3
   |
   +---Net::Packet::DescL4

Net::Packet::Frame

Net::Packet::Layer
   |
   +---Net::Packet::Layer2
   |      |
   |      +---Net::Packet::ETH
   |      |
   |      +---Net::Packet::NULL
   |      |
   |      +---Net::Packet::RAW
   |      |
   |      +---Net::Packet::SLL
   |
   +---Net::Packet::Layer3
   |      |
   |      +---Net::Packet::ARP
   |      |
   |      +---Net::Packet::IPv4
   |      |
   |      +---Net::Packet::IPv6
   |      |
   |      +---Net::Packet::VLAN
   |      |
   |      +---Net::Packet::PPPoE
   |      |
   |      +---Net::Packet::PPP
   |      |
   |      +---Net::Packet::LLC
   |
   +---Net::Packet::Layer4
   |      |
   |      +---Net::Packet::TCP
   |      |
   |      +---Net::Packet::UDP
   |      |
   |      +---Net::Packet::ICMPv4
   |      |
   |      +---Net::Packet::PPPLCP
   |      |
   |      +---Net::Packet::CDP
   |
   +---Net::Packet::Layer7

DESCRIPTION

This module is a unified framework to craft, send and receive packets at layers 2, 3, 4 and 7.

Basically, you forge each layer of a frame (Net::Packet::IPv4 for layer 3, Net::Packet::TCP for layer 4; for example), and pack all of this into a Net::Packet::Frame object. Then, you can send the frame to the network, and receive its response easily, because the response is automatically searched for and matched against the request (not implemented for all layers).

If you want some layer 2, 3 or 4 protocol encoding/decoding to be added, just ask, and give a corresponding .pcap file ;). You can also subscribe to netpacket-users@gomor.org by sumply sending an e-mail requesting for it.

You should study various pod found in all classes, example files found in examples directory that come with this tarball, and also tests in t directory.

AUTHOR

Patrice <GomoR> Auffret

COPYRIGHT AND LICENSE

Copyright (c) 2004-2006, Patrice <GomoR> Auffret

You may distribute this module under the terms of the Artistic license. See LICENSE.Artistic file in the source distribution archive.

RELATED MODULES

NetPacket, Net::RawIP, Net::RawSock