Find TiVos on the LAN

findtivos.py

#!/usr/bin/env python

# The way this is supposed to work is, we broadcast an announcement to 
# port 2190, and wait for responses in kind. But that takes forever. The 
# TiVo Connect Discovery spec says that machines should speed up their 
# broadcast rate when they see a new machine on the network; in 
# practice, it appears that TiVo Desktop does so, but real TiVo boxes 
# don't -- they broadcast at ~65-second intervals, and don't change.
#
# However, they do respond _immediately_ with an HTTP request for a list 
# of services, when the TCD packet says they're available, and it's an 
# identity the TiVo hasn't seen before. So, that's what I've done here: 
# set up a fake HTTP server to catch the requests.

import random
import re
import select
import socket

ANNOUNCE = """tivoconnect=1
method=broadcast
platform=pc
identity=remote%(port)d
services=TiVoMediaServer:%(port)d/http
"""

tcd_id = re.compile('TiVo_TCD_ID: (.*)\r\n').search

tivos = {}

# Find and bind a free port for our fake server.
hsock = socket.socket()
while True:
    port = random.randint(32768, 65535)
    try:
        hsock.bind(('', port))
        break
    except:
        pass

hsock.listen(5)

# Broadcast an announcement.
usock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
usock.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
usock.sendto(ANNOUNCE % locals(), ('255.255.255.255', 2190))
usock.close()

# Collect the queries made in response. These come quickly.
while True:
    isock, junk1, junk2 = select.select([hsock], [], [], 0.1)
    if not isock:
        break
    client, address = hsock.accept()
    message = client.recv(1500)
    client.close()  # This is rather rude.
    print message
    tivos[tcd_id(message).groups()[0]] = address[0]

hsock.close()

for key in tivos:
    print key, tivos[key]