Wifi sniffer capability; often asked for, never delivered?

[drgdhorler]

Hello!

Covid -19 has given me time to ressurect my embedded experiments!

I've noted that there are a number of esp32 solutions to "promiscuous" wifi sniffing (mostly in "C"), indeed Zerynth provide a "compiled python solution" that can be targeted to the pycom modules. Over the years there have been requests for this facility in Pycom; so my question is, "Does WIFI sniffing exist, will it ever exist? If it does where is the documentation, examples etc. For sure a "work round" solution can be created that uses a slave esp32 running alongside a Pycom module, but this is not very elegant.

I'm keen to have an answer, please.

Many thanks in advance.

[Xykon]

@drgdhorler We added experimental support for this. Below is some example code to capture MAC addresses.

from network import WLAN
import ubinascii



def pack_cb(pack):
    mac = bytearray(6)
    pk = wlan.wifi_packet()
    control = pk.data[0]
    subtype = (0xF0 & control) >> 4
    type = 0x0C & control
    #print("Control:{}, subtype:{}, type:{}".format(control, subtype, type))
    if subtype == 4:
        for i in range (0,6):
            mac[i] = pk.data[10 + i]
        print ("Wifi Node with MAC: {}".format(ubinascii.hexlify(mac)))

wlan = WLAN(mode=WLAN.STA, antenna=WLAN.EXT_ANT)
wlan.callback(trigger=WLAN.EVENT_PKT_MGMT, handler=pack_cb)
wlan.promiscuous(True)