NAME¶
get-oui - Fetch the arp-scan OUI file from the IEEE website
SYNOPSIS¶
get-oui [
options]
DESCRIPTION¶
get-oui fetches the Ethernet OUI file from the IEEE website, and saves it
in the format used by arp-scan.
The OUI file contains all of the OUIs (Organizationally Unique Identifiers) that
have been registered with IEEE. Each OUI entry in the file specifies the first
24-bits of the 48-bit Ethernet hardware address, leaving the remaining 24-bits
for use by the registering organisation. For example the OUI entry
"080020", registered to Sun Microsystems, applies to any Ethernet
hardware address from
08:00:20:00:00:00 to
08:00:20:ff:ff:ff
inclusive. Each OUI assignment represents a total of 2^24 (16,777,216)
Ethernet addresses.
Every major Ethernet hardware vendor registers an OUI for their equipment, and
larger vendors will need to register more than one. For example, 3Com have a
total of 37 OUI entries. Organisations that only produce a small number of
Ethernet devices will often obtain an IAB registration instead. See
get-iab(1) for details.
This script can be used to update the
arp-scan OUI file from the latest
data on the IEEE website. Most of the Ethernet addresses in use belong to an
OUI registration, so this is the most important of the files that
arp-scan uses to decode Ethernet hardware addresses. You should
therefore run
get-oui occasionally to keep the
arp-scan OUI file
up to date.
The OUI data is fetched from the URL
http://standards.ieee.org/regauth/oui/oui.txt and the output file is
saved to the file
ieee-oui.txt in the current directory. The URL to
fetch the data from can be changed with the
-u option, and the output
file name can be changed with the
-f option.
The
ieee-oui.txt file that is produced by this script is used by
arp-scan to determine the Ethernet card vendor from its hardware
address.
The directory that
arp-scan will look for the
ieee-oui.txt file
depends on the options used when it was built. If it was built using the
default options, then it will look in
/usr/local/share/arp-scan.
OPTIONS¶
- -h
- Display a brief usage message and exit.
- -f <fn>
- Write the output to the specified file instead of the
default ieee-oui.txt.
- -u <URL>
- Use the specified URL to fetch the raw OUI data from
instead of the default
http://standards.ieee.org/regauth/oui/oui.txt.
- -v
- Display verbose progress messages.
FILES¶
- ieee-oui.txt
- The default output file.
EXAMPLES¶
$ get-oui -v
Renaming ieee-oui.txt to ieee-oui.txt.bak
Fetching OUI data from http://standards.ieee.org/regauth/oui/oui.txt
Fetched 1467278 bytes
Opening output file ieee-oui.txt
9274 OUI entries written to file ieee-oui.txt
NOTES¶
get-oui is implemented in Perl, so you need to have the Perl interpreter
installed on your system to use it.
get-oui uses the
LWP::Simple Perl module to fetch the data from
the IEEE website. You must have this module installed on your system for it to
work. This module is available on most distributions, often called
libwww-perl. It is also available in source form from CPAN.
You can use a proxy server by defining the
http_proxy environment
variable.
AUTHOR¶
Roy Hills <Roy.Hills@nta-monitor.com>
SEE ALSO¶
- arp-scan(1)
- get-iab(1)
- arp-fingerprint(1)
http://www.nta-monitor.com/wiki/ The arp-scan wiki page.
