`NetPacket::IGMP' - Assemble and disassemble IGMP (Internet Group Mangement Protocol) packets. 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); `NetPacket::IGMP' provides a set of routines for assembling and disassembling packets using IGMP (Internet Group Mangement Protocol).

Methods
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. Return an IGMP packet encoded with the instance data specified. Not implemented.

Functions
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. The IGMP version of this packet. The message type for this packet. The length (including length of header) in bytes for this packet. The message subtype for this packet. The checksum for this packet. The group address specified in this packet. The encapsulated data (payload) for this packet.

Exports
none IGMP_VERSION_RFC998 IGMP_VERSION_RFC1112 IGMP_HOST_MQUERY IGMP_HOST_MREPORT IGMP_IP_NO_HOSTS IGMP_IP_ALL_HOSTS IGMP_IP_ALL_ROUTERS The following tags group together related exportable items. Import the strip function `igmp_strip'. IGMP_VERSION_RFC998 IGMP_VERSION_RFC1112 IGMP_HOST_MQUERY IGMP_HOST_MREPORT IGMP_IP_NO_HOSTS IGMP_IP_ALL_HOSTS IGMP_IP_ALL_ROUTERS All the above exportable items. 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'); Copyright (c) 2001 Tim Potter. This package is free software and is provided "as is" without express or implied warranty. It may be used, redistributed and/or modified under the terms of the Perl Artistic License (see http://www.perl.com/perl/misc/Artistic.html) Copyright (c) 1995,1996,1997,1998,1999 ANU and CSIRO on behalf of the participants in the CRC for Advanced Computational Systems ('ACSys'). ACSys makes this software and all associated data and documentation ('Software') available free of charge. You may make copies of the Software but you must include all of this notice on any copy. The Software was developed for research purposes and ACSys does not warrant that it is error free or fit for any purpose. ACSys disclaims any liability for all claims, expenses, losses, damages and costs any user may incur as a result of using, copying or modifying the Software. Tim Potter <tpot@samba.org>