You’re in the city and there are all sorts of wifi networks crackling around you! Well, good news, you can analyze and map all of it like you would with nmap. Except there’s no need to connect to these wifi networks or even have them broadcast an SSID.
The tool that allows this feat is called TrackerJacker. It’s a command-line tool that simply allows you to do 802.11 monitoring on Linux (including Raspberry Pi) and macOS.
This allows you to not only have a list of wifi networks, but also all the devices connected to them. On your own wifi network, this can also help you find the device that’s hogging all the bandwidth.
To install it:
pip3 install trackerjacker
You can also track certain MAC addresses if needed and then trigger alerts or any kind of scripts. Imagine, you have someone’s MAC address who needs to stay away from you… Well, you can instantly know if they’re around when they connect to a wifi network around you :-).
To map everything around you, you can also use the following command, specifying the network interface to use (here eth0):
trackerjacker -i eth0 --map
You’ll then get a YAML file named wifi_map.yaml.
In short, a nice little tool developed in Python to try out. The entire documentation is available on Github.”