NAME

Net::MAC::Vendor - look up the vendor for a MAC

SYNOPSIS

use Net::MAC::Vendor;

my $mac = "00:0d:93:29:f6:c2";

my $array = Net::MAC::Vendor::lookup( $mac );

You can also run this as a script with as many arguments as you like. The module realizes it is a script, looks up the information for each MAC, and outputs it.

perl Net/MAC/Vendor.pm 00:0d:93:29:f6:c2 00:0d:93:29:f6:c5

DESCRIPTION

The Institute of Electrical and Electronics Engineers (IEEE) assigns an Organizational Unique Identifier (OUI) to manufacturers of network interfaces. Each interface has a Media Access Control (MAC) address of six bytes. The first three bytes are the OUI.

This module allows you to take a MAC address and turn it into the OUI and vendor information. You can, for instance, scan a network, collect MAC addresses, and turn those addresses into vendors. With vendor information, you can often guess at what what you are looking at (e.g. an Apple product).

You can use this as a module as its individual functions, or call it as a script with a list of MAC addresses as arguments. The module can figure it out.

This module tries to persistently cache with DBM::Deep the OUI information so it can avoid using the network. If it cannot load DBM::Deep, it uses a normal hash (which is lost when the process finishes). You can preload this cache with the load_cache() function. So far, the module looks in the current working directory for a file named mac_oui.db to find the cache. I need to come up with a way to let the user set that location.

Functions

run( @macs )

If I call this module as a script, this class method automatically runs. It takes the MAC addresses and prints the registered vendor information for each address. I can pass it a list of MAC addresses and run() processes each one of them. It prints out what it discovers.

This method does try to use a cache of OUI to cut down on the times it has to access the network. If the cache is fully loaded (perhaps using load_cache), it may not even use the network at all.

lookup( MAC )

Given the MAC address, return an anonymous array with the vendor information. The first element is the OUI, the second element is the vendor name, and the remaining elements are the address lines. Different records may have different numbers of lines, although the first two should be consistent.

The normalize_mac() function explains the possible formants for MAC.

normalize_mac( MAC )

Takes a MAC address and turns it into the form I need to send to the IEEE lookup, which is the first six bytes in hex separated by hyphens. For instance, 00:0d:93:29:f6:c2 turns into 00-0D-93.

The input string can be a separated by colons or hyphens. They can omit leading 0's (which might make things look odd). We only need the first three bytes

00:0d:93:29:f6:c2   # usual form

00-0d-93-29-f6-c2   # with hyphens

00:0d:93            # first three bytes

0:d:93              # missing leading zero

:d:93               # missing all leading zeros

fetch_oui( MAC )

Looks up the OUI information on the IEEE website, or uses a cached version of it. Pass it the result of normalize_mac() and you should be fine.

The normalize_mac() function explains the possible formants for MAC.

To avoid multiple calls on the network, use load_cache to preload the entire OUI space into an in-memory cache. This can take a long time over a slow network, thoug; the file is about 60,000 lines.

fetch_oui_from_ieee( MAC )

Looks up the OUI information on the IEEE website. Pass it the result of normalize_mac() and you should be fine.

The normalize_mac() function explains the possible formants for MAC.

fetch_oui_from_cache( MAC )

Looks up the OUI information in the cached OUI information (see load_cache).

The normalize_mac() function explains the possible formats for MAC.

To avoid multiple calls on the network, use load_cache to preload the entire OUI space into an in-memory cache.

If it doesn't find the MAC in the cache, it returns nothing.

extract_oui_from_html( HTML )

Gets rid of the HTML around the OUI information. It may still be ugly. The HTML is the search results page of the IEEE ouisearch lookup.

Returns false if it could not extract the information. This could mean unexpected input or a change in format.

parse_oui( STRING )

Takes a string that looks like

00-03-93   (hex)            Apple Computer, Inc.
000393     (base 16)        Apple Computer, Inc.
							20650 Valley Green Dr.
							Cupertino CA 95014
							UNITED STATES

and turns it into an array of lines. It discards the first line, strips the leading information from the second line, and strips the leading whitespace from all of the lines.

With no arguments, it returns an empty anonymous array.

load_cache( [ SOURCE ] )

Downloads the current list of all OUIs, parses it with parse_oui(), and stores it in $Cached anonymous hash keyed by the OUIs (i.e. 00-0D-93). The fetch_oui() will use this cache if it exists. The cache is stored as a DBM::Deep file named after the NET_MAC_VENDOR_CACHE environment variable, or mac_oui.db by default.

By default, this uses http://standards.ieee.org/regauth/oui/oui.txt , but given an argument, it tries to use that. To load from a local file, use the file:// scheme.

If load_cache cannot load the data, it issues a warning and returns nothing.

SEE ALSO

Net::MacMap

SOURCE AVAILABILITY

This source is part of a SourceForge project which always has the latest sources in CVS, as well as all of the previous releases.

http://sourceforge.net/projects/brian-d-foy/

If, for some reason, I disappear from the world, one of the other members of the project can shepherd this module appropriately.

AUTHOR

brian d foy <bdfoy@cpan.org>

COPYRIGHT AND LICENSE

Copyright (c) 2004-2007 brian d foy. All rights reserved.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.