Use stem's new circuit timeout feature in 1.6.0-dev (1102cbd5) · Commits · The Tor Project / Network Health / sbws

sbws/lib/circuitbuilder.py

+7 −80

Original line number	Diff line number	Diff line
		from stem import CircuitExtensionFailed, InvalidRequest, ProtocolError
		from stem import CircuitExtensionFailed, InvalidRequest, ProtocolError, Timeout
		from stem import InvalidArguments
		from stem.control import CircStatus, EventType
		import random
		@@ -48,6 +48,7 @@ class CircuitBuilder:
		self.relay_list = RelayList(args, conf, self.controller)
		self.built_circuits = set()
		self.close_circuits_on_exit = close_circuits_on_exit
		self.circuit_timeout = conf.getint('general', 'circuit_timeout')

		@property
		def relays(self):
		@@ -82,93 +83,19 @@ class CircuitBuilder:
		raise PathLengthException()
		c = self.controller
		assert stem_utils.is_controller_okay(c)
		timeout = self.circuit_timeout
		fp_path = '[' + ' -> '.join([p[0:8] for p in path]) + ']'
		log.debug('Building %s', fp_path)
		ignore_events = [CircStatus.LAUNCHED, CircStatus.EXTENDED]
		event_queue = queue.Queue(maxsize=3)

		def event_listener(event):
		event_queue.put(event)

		stem_utils.add_event_listener(c, event_listener, EventType.CIRC)
		for _ in range(0, 3):
		circ_built = False
		# The time we started trying to build the circuit. An offset of
		# this is when we know we should give up
		start_time = time.time()
		try:
		# To work around ORCONNs not timing out for a long time, we
		# need to NOT let stem block on the circuit to be built, but do
		# the blocking ourselves.
		circ_id = c.new_circuit(path, await_build=False)
		while True:
		try:
		# If the timeout is hit, this will throw queue.Empty.
		# Otherwise it will return the event
		circ = event_queue.get(block=True, timeout=1)
		except queue.Empty:
		circ = None
		# This is the common place to allow ourselves to give
		# up. We will usually not get an event at roughly the
		# same time we want to give up
		if start_time + 10 < time.time():
		log.warning(
		'Could not build circ %s %s fast enough. '
		'Giving up on it.', circ_id, fp_path)
		break
		else:
		# If it isn't time to give up, we need to skip the
		# remaining part of this loop because we don't have
		# a circ event.
		continue
		# We have a circ event! Make sure it is for the circuit
		# we are waiting on
		if circ.id != circ_id:
		pass
		# Make sure it isn't an uninterseting event
		elif circ.status in ignore_events:
		pass
		# This is the good case! We are finally done
		elif circ.status == CircStatus.BUILT:
		circ_built = True
		break
		# This is a bad case. We are done, but the circuit doesn't
		# exist
		elif circ.status == CircStatus.FAILED:
		break
		# This is a bad case. We are done, but the circuit doesn't
		# exist
		elif circ.status == CircStatus.CLOSED:
		break
		# This is a case we weren't expecting
		else:
		log.warning(
		'We weren\'t expecting to get a circ status '
		'of %s when waiting for circ %s %s to build. '
		'Ignoring.',
		circ.status, circ_id, fp_path)
		pass
		# If we made it this far, we always want to check if we
		# should give up and return the build status that we've
		# determined
		if start_time + 10 < time.time():
		log.warning(
		'We\'ve waited long enough for circ %s %s. %s',
		circ_id, fp_path, 'It became built at the last '
		'second.' if circ_built else 'It was never '
		'built.')
		break
		circ_id = c.new_circuit(
		path, await_build=True, timeout=timeout)
		except (InvalidRequest, CircuitExtensionFailed,
		ProtocolError) as e:
		ProtocolError, Timeout) as e:
		log.warning(e)
		continue
		if circ_built:
		stem_utils.remove_event_listener(c, event_listener)
		self.built_circuits.add(circ_id)
		return circ_id
		else:
		self.close_circuit(circ_id)
		stem_utils.remove_event_listener(c, event_listener)
		return circ_id
		return None

		def __del__(self):

sbws/util/stem.py

+8 −9

Original line number	Diff line number	Diff line
		@@ -114,17 +114,16 @@ def _init_controller_socket(socket):

		def launch_tor(conf):
		assert isinstance(conf, ConfigParser)
		section = conf['tor']
		os.makedirs(section['datadir'], mode=0o700, exist_ok=True)
		os.makedirs(conf['tor']['datadir'], mode=0o700, exist_ok=True)
		# Bare minimum things, more or less
		torrc = copy.deepcopy(TORRC_STARTING_POINT)
		# Very important and/or common settings that we don't know until runtime
		torrc.update({
		'DataDirectory': section['datadir'],
		'PidFile': os.path.join(section['datadir'], 'tor.pid'),
		'ControlSocket': section['control_socket'],
		'DataDirectory': conf['tor']['datadir'],
		'PidFile': os.path.join(conf['tor']['datadir'], 'tor.pid'),
		'ControlSocket': conf['tor']['control_socket'],
		'Log': [
		'NOTICE file {}'.format(section['log']),
		'NOTICE file {}'.format(conf['tor']['log']),
		],
		# Things needed to make circuits fail a little faster. We get the
		# circuit_timeout as a string instead of an int on purpose: stem only
		@@ -147,7 +146,7 @@ def launch_tor(conf):
		# extra_lines =
		# Log debug file /tmp/tor-debug.log
		# NumCPUs 1
		for line in section['extra_lines'].split('\n'):
		for line in conf['tor']['extra_lines'].split('\n'):
		# Remove leading and trailing whitespace, if any
		line = line.strip()
		# Ignore blank lines
		@@ -183,13 +182,13 @@ def launch_tor(conf):
		stem.process.launch_tor_with_config(
		torrc, init_msg_handler=log.debug, take_ownership=True)
		# And return a controller to it
		cont = _init_controller_socket(section['control_socket'])
		cont = _init_controller_socket(conf['tor']['control_socket'])
		assert is_controller_okay(cont)
		# Because we build things by hand and can't set these before Tor bootstraps
		cont.set_conf('__DisablePredictedCircuits', '1')
		cont.set_conf('__LeaveStreamsUnattached', '1')
		log.info('Started and connected to Tor %s via %s', cont.get_version(),
		section['control_socket'])
		conf['tor']['control_socket'])
		return cont