Threaded port scanner for finding chromecasts

portscan.py

#!/usr/bin/env python
"""
Does a quick scan of the current subnet for the specified IP range and ports

- Used to find a listening chromecast

"""
import threading
import time

from Queue import Queue
from socket import *

CURRENT_IP = gethostbyname(gethostname())
IP_BLOCK = CURRENT_IP[:CURRENT_IP.rfind('.')]
START_IP = 1
END_IP = 255
TARGET_PORTS = [8008, ]# 80]
DEBUGGING_PORTS = [9222,]
ALL_PORTS = TARGET_PORTS + DEBUGGING_PORTS

MAX_THREADS = END_IP - START_IP # One thread per IP

print_lock = threading.Lock()
target_ips = Queue()

chromecasts = []
debuggable_chromecasts = []


def worker(target_ip):
    """
    Do the work the thread is trying to accomplish

    """
  
    # Normal Ports
    for target_port in TARGET_PORTS:
      s = socket(AF_INET, SOCK_STREAM)
      result = s.connect_ex((target_ip, target_port))

      if(result == 0) :
        chromecasts.append(target_ip);

      s.close()

    # Debugging ports
    for target_port in DEBUGGING_PORTS:
      s = socket(AF_INET, SOCK_STREAM)
      result = s.connect_ex((target_ip, target_port))

      if(result == 0) :
        debuggable_chromecasts.append(target_ip);

      s.close()



def threader():
  """
  Process the target ip queue using all available threads

  """
  while True:
    target_ip = target_ips.get()
    worker(target_ip)
    target_ips.task_done()


if __name__ == '__main__':
  print 'Starting scan of {}.{}-{} on ports {}...'.format(IP_BLOCK, START_IP, END_IP, ','.join(str(port) for port in ALL_PORTS))

  # Set the default socket timeout.
  setdefaulttimeout(0.1)

  # Create our worker threads
  for thread_number in xrange(MAX_THREADS):
    thread = threading.Thread(target=threader)
    thread.daemon = True
    thread.start()

  start = time.time()

  # Build task queue
  for ip in range(START_IP, END_IP):
    target_ip = '{block}.{ip}'.format(block=IP_BLOCK, ip=ip)
    target_ips.put(target_ip)

  # Wait until threading stops
  target_ips.join()

  if len(chromecasts) > 0:
    print '\nFound running chromecasts at:'

    for chromecast in chromecasts:
      print chromecast
  else:
    print '\nNo running chromecasts could be found.'



  if len(debuggable_chromecasts) > 0:
    print '\nThese chromecasts can be debugged:'

    for chromecast in debuggable_chromecasts:
      print chromecast
  else:
    print '\nNo running chromecasts can be debugged.'

  print('\nScanning took: {:.2f}s'.format(time.time() - start))

Looks for open debugging ports on the current LAN segment so you can figure out the IP of your chromecast.