DOKK / manpages / debian 12 / libnetpacket-perl / NetPacket::ICMP.3pm.en
NetPacket::ICMP(3pm) User Contributed Perl Documentation NetPacket::ICMP(3pm)

NetPacket::ICMP - Assemble and disassemble ICMP (Internet Control Message Protocol) packets.

version 1.7.2

  use NetPacket::ICMP;
  $icmp_obj = NetPacket::ICMP->decode($raw_pkt);
  $icmp_pkt = NetPacket::ICMP->encode();
  $icmp_data = NetPacket::ICMP::strip($raw_pkt);

"NetPacket::ICMP" provides a set of routines for assembling and disassembling packets using ICMP (Internet Control Message Protocol).

"NetPacket::ICMP->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::ICMP->encode()"
Return an ICMP packet encoded with the instance data specified.

"NetPacket::ICMP::strip([RAW PACKET])"
Return the encapsulated data (or payload) contained in the ICMP packet.

The instance data for the "NetPacket::ICMP" object consists of the following fields.

The ICMP message type of this packet.
The ICMP message code of this packet.
The checksum for this packet.
The encapsulated data (payload) for this packet.

none
ICMP message types:
ICMP_ECHOREPLY ICMP_UNREACH ICMP_SOURCEQUENCH
ICMP_REDIRECT ICMP_ECHO ICMP_ROUTERADVERT
ICMP_ROUTERSOLICIT ICMP_TIMXCEED ICMP_PARAMPROB
ICMP_TSTAMP ICMP_TSTAMPREPLY ICMP_IREQ ICMP_IREQREPLY
ICMP_MASKREQ ICMP_MASKREPLY
The following tags group together related exportable items.
":types"
  ICMP_ECHOREPLY ICMP_UNREACH ICMP_SOURCEQUENCH
  ICMP_REDIRECT ICMP_ECHO ICMP_ROUTERADVERT
  ICMP_ROUTERSOLICIT ICMP_TIMXCEED ICMP_PARAMPROB
  ICMP_TSTAMP ICMP_TSTAMPREPLY ICMP_IREQ
  ICMP_IREQREPLY ICMP_MASKREQ ICMP_MASKREPLY
":strip"
Import the strip function "icmp_strip".
":ALL"
All the above exportable items.

The following example prints the ICMP type, code, and checksum fields.

  #!/usr/bin/perl -w
  use strict;
  use Net::PcapUtils;
  use NetPacket::Ethernet qw(:strip);
  use NetPacket::IP qw(:strip);
  use NetPacket::ICMP;
  sub process_pkt {
      my ($user, $hdr, $pkt) = @_;
      my $ip_obj = NetPacket::IP->decode(eth_strip($pkt));
      my $icmp_obj = NetPacket::ICMP->decode(ip_strip($ip_obj));
      print("Type: $icmp_obj->{type}\n");
      print("Code: $icmp_obj->{code}\n");
      print("Checksum: $icmp_obj->{cksum}\n\n");
  }
  Net::PcapUtils::loop(\&process_pkt, FILTER => 'icmp');

Copyright (c) 2001 Tim Potter and Stephanie Wehner.

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.

Tim Potter <tpot@samba.org>

Stephanie Wehner <atrak@itsx.com>

2022-11-19 perl v5.36.0