Use wpa_cli to print hostnames of nearby cisco APs

wlan-info.py

from subprocess import run, CalledProcessError
from time import sleep

CMD = ["wpa_cli"]

def scan_results(_scan=True):
    res = []

    proc = run(CMD + ["scan_results"],
            check=True, capture_output=True)

    for line in proc.stdout.splitlines():
        if line[2] != ord(':') or line[5] != ord(':'):
            continue

        line = line.split(b'\t')
        res.append((
            line[0].decode('ascii'),
            int(line[1])/1000,
            int(line[2]),
            line[3].decode('ascii'),
            line[4].decode('ascii')))

    if len(res) == 1 and _scan:
        run(CMD + ['scan'], check=True, capture_output=True)
        sleep(10)
        return scan_results(_scan=False)

    return res

def status():
    proc = run(CMD + ['status'], check=True, capture_output=True)
    x = filter(lambda x: x[:3] == b'bssid=', proc.stdout.splitlines())
    return next(x)[6:].decode('ascii')

def get_ie(bssid):
    proc = run(CMD + ['bss', bssid], check=True, capture_output=True)
    x = filter(lambda x: x[:3] == b'ie=', proc.stdout.splitlines())
    x = next(x)[3:]
    ie = []
    while x:
        ie.append(int(x[:2], 16))
        x = x[2:]
    return bytes(ie)

def parse_ie(ie):
    res = []
    while ie:
        t = ie[0]
        l = ie[1]
        v = ie[2:2+l]
        ie = ie[2+l:]
        res.append((t, v))
    return res

def parse_schissko(buf):
    name = buf[10:25].decode('ascii')

    # indicate omission
    if name[-1] != '\0':
        name += '…'

    # remove padding
    while name[-1] == '\0':
        name = name[:-1]

    return name

hexstr = lambda x: ' '.join(["%02x" % y for y in x])

for bssid, freq, signal, flags, ssid in scan_results():
    ies = parse_ie(get_ie(bssid))
    for value in filter(lambda x: x[0] == 133, ies):
        print("%s\t%3.1f\t%5i\t%s" % (
            bssid, freq, signal, parse_schissko(value[1])))