Search for host with MAC-address using Python

Question

I'd like to search for a given MAC address on my network, all from within a Python script. I already have a map of all the active IP addresses in the network but I cannot figure out how to glean the MAC address. Any ideas?

Answer 1

Depends on your platform. If you're using *nix, you can use the 'arp' command to look up the mac address for a given IP (assuming IPv4) address. If that doesn't work, you could ping the address and then look, or if you have access to the raw network (using BPF or some other mechanism), you could send your own ARP packets (but that is probably overkill).

Answer 2

You would want to parse the output of 'arp', but the kernel ARP cache will only contain those IP address(es) if those hosts have communicated with the host where the Python script is running.

ifconfig can be used to display the MAC addresses of local interfaces, but not those on the LAN.

Answer 3

If you want a pure Python solution, you can take a look at Scapy to craft packets (you need to send ARP request, and inspect replies). Or if you don't mind invoking external program, you can use arping (on Un*x systems, I don't know of a Windows equivalent).

Answer 4

You need ARP. Python's standard library doesn't include any code for that, so you either need to call an external program (your OS may have an 'arp' utility) or you need to build the packets yourself (possibly with a tool like Scapy.

Answer 5

It seems that there is not a native way of doing this with Python. Your best bet would be to parse the output of "ipconfig /all" on Windows, or "ifconfig" on Linux. Consider using os.popen() with some regexps.

Answer 6

I don't think there is a built in way to get it from Python itself.

My question is, how are you getting the IP information from your network?

To get it from your local machine you could parse ifconfig (unix) or ipconfig (windows) with little difficulty.