NAME¶
NetPacket::IGMP - Assemble and disassemble IGMP (Internet Group Mangement
Protocol) packets.
VERSION¶
version 1.3.0
SYNOPSIS¶
use NetPacket::IGMP;
$igmp_obj = NetPacket::IGMP->decode($raw_pkt);
$igmp_pkt = NetPacket::IGMP->encode(params...); # Not implemented
$igmp_data = NetPacket::IGMP::strip($raw_pkt);
DESCRIPTION¶
"NetPacket::IGMP" provides a set of routines for assembling and
disassembling packets using IGMP (Internet Group Mangement Protocol).
Methods¶
- "NetPacket::IGMP->decode([RAW PACKET])"
- Decode the raw packet data given and return an object
containing instance data. This method will quite happily decode garbage
input. It is the responsibility of the programmer to ensure valid packet
data is passed to this method.
- "NetPacket::IGMP->encode(param =>
value)"
- Return an IGMP packet encoded with the instance data
specified. Not implemented.
Functions¶
- "NetPacket::IGMP::strip([RAW PACKET])"
- Return the encapsulated data (or payload) contained in the
IGMP packet. This function returns undef as there is no encapsulated data
in an IGMP packet.
Instance data¶
The instance data for the "NetPacket::IGMP" object consists of the
following fields.
- version
- The IGMP version of this packet.
- type
- The message type for this packet.
- len
- The length (including length of header) in bytes for this
packet.
- subtype
- The message subtype for this packet.
- cksum
- The checksum for this packet.
- group_addr
- The group address specified in this packet.
- data
- The encapsulated data (payload) for this packet.
Exports¶
- default
- none
- exportable
- IGMP_VERSION_RFC998 IGMP_VERSION_RFC1112 IGMP_HOST_MQUERY
IGMP_HOST_MREPORT IGMP_IP_NO_HOSTS IGMP_IP_ALL_HOSTS
IGMP_IP_ALL_ROUTERS
- tags
- The following tags group together related exportable
items.
- ":strip"
- Import the strip function "igmp_strip".
- ":versions"
- IGMP_VERSION_RFC998 IGMP_VERSION_RFC1112
- ":msgtypes"
- IGMP_HOST_MQUERY IGMP_HOST_MREPORT
- ":group_addrs"
- IGMP_IP_NO_HOSTS IGMP_IP_ALL_HOSTS IGMP_IP_ALL_ROUTERS
- ":ALL"
- All the above exportable items.
EXAMPLE¶
The following script dumps UDP frames by IP address and UDP port to standard
output.
#!/usr/bin/perl -w
use strict;
use Net::PcapUtils;
use NetPacket::Ethernet qw(:strip);
use NetPacket::IP;
use NetPacket::IGMP;
sub process_pkt {
my($arg, $hdr, $pkt) = @_;
my $ip_obj = NetPacket::IP->decode(eth_strip($pkt));
my $igmp_obj = NetPacket::IGMP->decode($ip_obj->{data});
print("$ip_obj->{src_ip} -> $ip_obj->{dest_ip} ",
"$igmp_obj->{type}/$igmp_obj->{subtype} ",
"$igmp_obj->{group_addr}\n");
}
Net::PcapUtils::loop(\&process_pkt, FILTER => 'igmp');
TODO¶
- Implement encode() function
COPYRIGHT¶
Copyright (c) 2001 Tim Potter.
Copyright (c) 1995,1996,1997,1998,1999 ANU and CSIRO on behalf of the
participants in the CRC for Advanced Computational Systems ('ACSys').
This module is free software. You can redistribute it and/or modify it under the
terms of the Artistic License 2.0.
This program is distributed in the hope that it will be useful, but without any
warranty; without even the implied warranty of merchantability or fitness for
a particular purpose.
AUTHOR¶
Tim Potter <tpot@samba.org>