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 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 formats 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, though; 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, OUI )
- 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 this:
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.
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.
This previously used DBM::Deep if it was installed, but that was much too
slow. Instead, if you want persistence, you can play with
$Net::MAC::Vendor::Cached yourself.
SEE ALSO¶
Net::MacMap
SOURCE AVAILABILITY¶
The source is in Github:
git://github.com/briandfoy/net-mac-vendor.git
AUTHOR¶
brian d foy "<bdfoy@cpan.org>"
COPYRIGHT AND LICENSE¶
Copyright (c) 2004-2014 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.