jbize/python-arpreq

Query the Kernel ARP cache for the MAC address of an IP address

arpreq

Python C extension to query the Kernel ARP cache for the MAC address of a given IP address.

Usage

The arpreq module exposes a single function arpreq, that will resolve a given IPv4 address into a MAC address.

An IP address can only be resolved to a MAC address if it is on the same subnet as your machine.

Let's assume your current machine has the address 192.168.1.10 and another machine with the address 192.168.1.1 is on the same subnet:

>>> import arpreq
>>> arpreq.arpreq('192.168.1.1')
'00:11:22:33:44:55'

If a IP address can not be resolved to an MAC address, None is returned.

>>> arpreq.arpreq('8.8.8.8') is None
True

IP addresses may be also be specified as int or rich IP address data type of the common ipaddr, ipaddress, or netaddr modules.

>>> arpreq.arpreq(0x7F000001)
'00:00:00:00:00:00'
>>> import netaddr
>>> arpreq.arpreq(netaddr.IPAddress('127.0.0.1'))
'00:00:00:00:00:00'
>>> import ipaddr # on Python 2
>>> arpreq.arpreq(ipaddr.IPv4Address('127.0.0.1'))
'00:00:00:00:00:00'
>>> import ipaddress
>>> arpreq.arpreq(ipaddress.IPv4Address(u'127.0.0.1'))
'00:00:00:00:00:00'

Supported Platforms

This extension has only been tested on Linux, it should however work on any platform that supports the SIOCGARP ioctl, which is virtually every BSD, Linux and Mac OS.

Changelog

v0.3.3 (2017-05-03)

• Disable PEP-489 on PyPy3
• Disable PyModule_GetState on PyPy3
• Provide a Debian package

v0.3.2 (2017-05-03)

• Support point-to-point veth pairs (See #6)
• Accept unicode objects on Python 2 and bytes objects on Python 3 (See #5)
• Some test improvements

v0.3.1 (2016-07-06)

• Don't use private _PyErr_ChainExceptions (breaks on Debian Jessie)

v0.3.0 (2016-06-26)

• Use PEP 489 multi-phase extension module initialization on Python 3.5+
• Close socket if module initialization failed
• Code cleanup

v0.2.1 (2016-06-26)

• Fix memset overflow

v0.2.0 (2016-06-09)

• Provide Python wheels
• Support int and rich IP address objects as IP address arguments
• Release the GIL during arpreq
• Add units tests
• Rework MAC string creation
• Restructure module initialization

v0.1.0 (2015-11-28)

• Initial release