Интерактивная система просмотра системных руководств (man-ов)
NetPacket::ARP (3)
>> NetPacket::ARP (3) ( Разные man: Библиотечные вызовы )
NAME
"NetPacket::ARP" - Assemble and disassemble ARP (Address Resolution
Protocol) packets.
SYNOPSIS
use NetPacket::ARP;
$tcp_obj = NetPacket::ARP->decode($raw_pkt);
$tcp_pkt = NetPacket::ARP->encode(params...); # Not implemented
DESCRIPTION
"NetPacket::ARP" provides a set of routines for assembling and
disassembling packets using ARP (Address Resolution Protocol).
Methods
NetPacket::ARP->decode([RAW PACKET])
Decode the raw packet data given and return an object containing
instance data. This method will quite happily decode garbage input.
It is the responsibility of the programmer to ensure valid packet data
is passed to this method.
NetPacket::ARP->encode(param => value)
Return a ARP packet encoded with the instance data specified. Not
implemented.
Functions
NetPacket::ARP::strip([RAW PACKET])
Return the encapsulated data (or payload) contained in the TCP packet.
Since no payload data is encapulated in an ARP packet (only instance
data), this function returns undef.
Instance data
The instance data for the "NetPacket::ARP" object consists of
the following fields.
htype
Hardware type.
proto
Protocol type.
hlen
Header length.
plen
Protocol length.
opcode
One of the following constants:
* ARP_OPCODE_REQUEST
* ARP_OPCODE_REPLY
* RARP_OPCODE_REQUEST
* RARP_OPCODE_REPLY
sha
Source hardware address.
spa
Source protocol address.
tha
Target hardware address.
tpa
Target protocol address.
Exports
default
none
exportable
none
tags
The following tags group together related exportable items.
:ALL
All the above exportable items.
EXAMPLE
Print out arp requests on the local network.
#!/usr/bin/perl -w
use Net::PcapUtils;
use NetPacket::Ethernet qw(:types);
use NetPacket::ARP;
sub process_pkt {
my ($arg, $hdr, $pkt) = @_;
my $eth_obj = NetPacket::Ethernet->decode($pkt);
if ($eth_obj->{type} == ETH_TYPE_ARP) {
my $arp_obj = NetPacket::ARP->decode($eth_obj->{data}, $eth_obj);
print("source hw addr=$arp_obj->{sha}, " .
"dest hw addr=$arp_obj->{tha}\n");
}
}
Net::PcapUtils::loop(\&process_pkt);
TODO
Implement encode() function
Does this work for protocols other than IP? Need to read RFC.
Example is a bit silly
COPYRIGHT
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.