#!/usr/bin/env python # # Copyright 2013 Jeff Rebeiro (jeff@rebeiro.net) All rights reserved # Simple SSDP implementation for PC Autobackup __author__ = 'jeff@rebeiro.net (Jeff Rebeiro)' import ConfigParser import logging import re from twisted.internet import reactor from twisted.internet.protocol import DatagramProtocol import common MSEARCH = re.compile(r'^M-SEARCH \* HTTP/1.1', re.DOTALL) MSEARCH_DATA = re.compile(r'^([^:]+):\s+(.*)') SSDP_RESPONSE = ('HTTP/1.1 200 OK\r\n' 'CACHE-CONTROL: max-age = 1800\r\n' 'EXT:\r\n' 'LOCATION: http://%s:52235/DMS/SamsungDmsDesc.xml\r\n' 'SERVER: MS-Windows/XP UPnP/1.0 PROTOTYPE/1.0\r\n' 'ST: urn:schemas-upnp-org:device:MediaServer:1\r\n' 'USN: %s::urn:schemas-upnp-org:device:MediaServer:1\r\n') class SSDPServer(DatagramProtocol): def __init__(self): self.logger = logging.getLogger('SSDPServer') self.config = common.LoadOrCreateConfig() def startProtocol(self): self.transport.setTTL(5) self.transport.joinGroup('239.255.255.250') def datagramReceived(self, datagram, address): m = MSEARCH.match(datagram) if m: # TODO(jrebeiro): Verify that MediaServer is the only discovery request # PCAutoBackup responds to. msearch_data = self.ParseSSDPDiscovery(datagram) address_info = ':'.join([str(x) for x in address]) if msearch_data.get('discovery_type'): self.logger.debug('Received SSDP M-SEARCH for %s from %s', msearch_data.get('discovery_type'), address_info) else: self.logger.debug('Received SSDP M-SEARCH from %s', address_info) if msearch_data.get('discovery_type') == 'MediaServer': self.SendSSDPResponse(address) def ParseSSDPDiscovery(self, datagram): parsed_data = {} for line in datagram.splitlines(): if line.startswith('M-SEARCH'): continue m = MSEARCH_DATA.match(line) if m: parsed_data[m.group(1)] = m.group(2) # ST: urn:schemas-upnp-org:device:MediaServer:1 if m.group(1) == 'ST': parsed_data['discovery_type'] = m.group(2).split(':')[3] return parsed_data def SendSSDPResponse(self, address): """Send a response to an SSDP MediaServer discovery request. Args: address: A tuple of destination IP and Port as strings """ response = SSDP_RESPONSE % (self.config.get('AUTOBACKUP', 'default_interface'), self.config.get('AUTOBACKUP', 'uuid')) address_info = ':'.join([str(x) for x in address]) self.logger.info('Sending SSDP response to %s', address_info) self.logger.debug('Response: %s', response) self.transport.write(response, address) def StartSSDPServer(): logging.info('SSDPServer started') reactor.listenMulticast(1900, SSDPServer()) reactor.run() def main(): logging_options = common.LOG_DEFAULTS logging_options['filename'] = 'ssdpserver.log' logging_options['level'] = logging.DEBUG logging.basicConfig(**logging_options) StartSSDPServer() if __name__ == "__main__": main()