We are currently working on a project, where we want to see the packets sent over WiFi. We are using an RPi zero w as a sniffer, and we have managed to use ioctl calls to get ssid and other informations, but only for the network we are currently connected to. How would we manage to scan for wifi packets from all incoming networks? And how would we go about getting the signal strength of those packets? If you have any links or suggestions to point us in the right direction, those would be very much appreciated.
We are using an RPi zero w with Raspbian Lite (Buster).