BestAPIdentifier.py

from sys import argv, exit
from os import popen, remove

def findBestAP(ssid, spec, privateConnect = False):
    validAPs = []
    with open('./dump.tmp', 'r') as f:
        while True:
            line = f.readline()
            if not line:
                break
            if 'BSS' in line and '\t' not in line:
                ap = []
                words = line.split(' ')
                BSS = words[1].split('(')
                ap.append(BSS[0])
                line = f.readline().strip()
                protectedNetwork = False
                while 'SSID' not in line:
                    line = f.readline().strip()
                    if 'freq' in line or 'signal' in line:
                        words = line.strip().split(' ')
                        ap.append(float(words[1]))
                    elif 'capability' in line and 'Privacy' in line and privateConnect == False:
                        protectedNetwork = True
                words = line.split(' ')
                if len(words) == 2:
                    ap.append(words[1])
                else:
                    ap.append('Unknown SSID')
                if ap[2] < -70 or (ssid != None and ssid != ap[3]) or protectedNetwork == True:
                    continue
                validAPs.append(tuple(ap))

    strongestSignal = -100
    bestAP = None
    for ap in validAPs:
        BSS, freq, signal, ssid = ap
        if signal > strongestSignal:
            if spec == None:
                strongestSignal = signal
                bestAP = ap
            elif spec == '2.4GHz' and freq < 3000:
                strongestSginal = signal
                bestAP = ap
            elif spec == '5.0GHz' and freq > 3000:
                strongestSginal = signal
                bestAP = ap

    return bestAP

def usage():
    print 'Usage: python bestAP.py NIC [-s SSID] [-f frequencySpectrum] [-p privateConnect]'
    print 'NIC: network interface controller'
    print '\tRun ifconfig and pick one till it works (or try wlan0)'
    print 'SSID: The Name of the Access Points you want to look for'
    print '\tOptional argument'
    print 'frequencySpectrum: the spectrum of frequency you want to connect to'
    print '\tOptional argument; Valid options are \'2.4GHz\' and \'5.0GHz\''
    print 'privateConnect: flag that details if you are want to be informed of private networks'
    print '\tOptional flag'

if __name__ == '__main__':

    if len(argv) < 2 or len(argv) > 6:
        usage()
        exit(0)  

    print 'Executing an external sudo command.'
    print 'If prompted for your password, know that I\'m not trying to steal it.'
    cmd = 'sudo iw dev %s scan > ./dump.tmp' % argv[1]
    print cmd
    popen(cmd)

    ssid = None
    freq = None
    private = False
    if '-s' in argv:
        ssid = argv[argv.index('-s') + 1]
    if '-f' in argv:
        freq = argv[argv.index('-f') + 1]
    if '-p' in argv:
        private = True

    bestAP = findBestAP(ssid, freq, private)
    if bestAP != None:
        BSS, freq, signal, SSID = bestAP
        print "%s (BSSID: %s) is the best AP in your range." % (SSID, BSS)
        print "frequency: %s MHz | signal Strength: %s" % (freq, signal)
    else:
        print "There is no available access point in your range conforming to your provided parameters."

    remove('./dump.tmp')