detect-raspis.py

#!/usr/bin/env python3
# -*- coding: utf-8; -*-
# Author: Santiago Saavedra <ssaavedra@gpul.org>
# License: MIT
# Description:
#   This script detects raspberries and sorts them by last-seen time.
#   It also tries to inspect whether they still have their default
#   password set.
#   We found it specially interesting in IoT Hackathons and the like
#   for participants to easily spot theirs (and actively remember
#   them to change their passwords).

from datetime import datetime
import os, pty, re, subprocess
from time import sleep

import urllib2 as request

import pxssh


raspis = []

dhcp_re = re.compile("^.*DHCPACK on ([0-9.]+) to ([a-f0-9:]+).*$")
raspi_manufacturer = 'b8:27:eb'

def hardware_matches(machine):
    return machine[:len(raspi_manufacturer)].lower() == raspi_manufacturer.lower()

def detect_raspis_dhcp():
    ## Modify this URL to point to a DHCP log so that we don't need to poke arp.
    url = "http://hackatoniot/dhcp.txt"
    f = request.urlopen(url)
    data = f.read()
    f.close()
    lines = data.split("\n")
    for line in lines:
	matches = dhcp_re.match(line)
	if matches:
	    if hardware_matches(matches.group(2)):
		# print("{0} matches hw {1}".format(line, matches.group(2)))
		yield matches.group(1)


def detect_raspis_nmap():
    ## Change NMAP range if it is another subnet.
    nmap_cmd = "sudo nmap -T5 -sP 192.168.13.0/24 | awk '/^Nmap/{ip=$NF}/B8:27:EB/{print ip}'"
    result = subprocess.check_output(nmap_cmd, shell=True)
    return result.split("\n")


def add_ordered_raspis(current_hardware=[]):
    for hw in current_hardware:
	if hw not in raspis:
	    raspis.insert(0, hw)

    for hw in list(raspis):
	if hw not in current_hardware:
	    raspis.remove(hw)

def check_default_pw(ip, user="pi", pw="raspberry"):
    s = pxssh.pxssh()
    s.force_password = True

    try:
	s.login(ip, user, pw)
	s.sendline('hostname')
	s.prompt()
	hostname = s.before
	s.logout()
	return "[INSECURE!]"
    except:
	return "[OK]"


def main():
    global raspis
    while True:
	current_hardware = set(detect_raspis_nmap())
	add_ordered_raspis(current_hardware)

	default_pw = {}

	for line in raspis:
	    default_pw[line] = check_default_pw(line)

	os.system('clear')
	print("Connected berries @ {0:%H:%M:%S}".format(datetime.now()))

	for line in raspis:
	    print("{ip} {maybeEnter}".format(ip=line, maybeEnter=default_pw[line]))

	sleep(10)

if __name__ == '__main__':
    main()