def _try_request(self):
"""
Try to consume a REQUEST message and respond whether we will accept the
request.
Will setup a TCP relay or an UDP socket to accommodate TCP RELAY and
UDP ASSOCIATE requests. After a TCP relay is set up the handler will
deactivate itself and change the Connection to a TcpRelayConnection.
Further data will be passed on to that handler.
:return: False if command could not been processes due to lack of bytes, True otherwise
"""
self._logger.debug("Client has sent PROXY REQUEST")
offset, request = conversion.decode_request(0, self.buffer)
if request is None:
return False
self.buffer = self.buffer[offset:]
assert isinstance(request, conversion.Request)
self.state = ConnectionState.PROXY_REQUEST_RECEIVED
try:
if request.cmd == conversion.REQ_CMD_UDP_ASSOCIATE:
self.on_udp_associate_request(self, request)
elif request.cmd == conversion.REQ_CMD_BIND:
response = conversion.encode_reply(
0x05, conversion.REP_SUCCEEDED, 0x00,
conversion.ADDRESS_TYPE_IPV4, "127.0.0.1", 1081)
self.transport.write(response)
self.state = ConnectionState.PROXY_REQUEST_ACCEPTED
elif request.cmd == conversion.REQ_CMD_CONNECT:
self._logger.info(
"TCP req to %s:%d support it. Returning HOST UNREACHABLE",
*request.destination)
response = conversion.encode_reply(
0x05, conversion.REP_HOST_UNREACHABLE, 0x00,
conversion.ADDRESS_TYPE_IPV4, "0.0.0.0", 0)
self.transport.write(response)
else:
self.deny_request(request, "CMD not recognized")
except:
response = conversion.encode_reply(
0x05, conversion.REP_COMMAND_NOT_SUPPORTED, 0x00,
conversion.ADDRESS_TYPE_IPV4, "0.0.0.0", 0)
self.transport.write(response)
self._logger.exception(
"Exception thrown, returning unsupported command response")
return True
def _try_request(self):
"""
Try to consume a REQUEST message and respond whether we will accept the
request.
Will setup a TCP relay or an UDP socket to accommodate TCP RELAY and
UDP ASSOCIATE requests. After a TCP relay is set up the handler will
deactivate itself and change the Connection to a TcpRelayConnection.
Further data will be passed on to that handler.
:return: False if command could not been processes due to lack of bytes, True otherwise
"""
self._logger.debug("Client has sent PROXY REQUEST")
offset, request = conversion.decode_request(0, self.buffer)
if request is None:
return False
self.buffer = self.buffer[offset:]
assert isinstance(request, conversion.Request)
self.state = ConnectionState.PROXY_REQUEST_RECEIVED
try:
if request.cmd == conversion.REQ_CMD_UDP_ASSOCIATE:
self.on_udp_associate_request(self, request)
elif request.cmd == conversion.REQ_CMD_BIND:
response = conversion.encode_reply(0x05, conversion.REP_SUCCEEDED, 0x00,
conversion.ADDRESS_TYPE_IPV4, "127.0.0.1", 1081)
self.transport.write(response)
self.state = ConnectionState.PROXY_REQUEST_ACCEPTED
elif request.cmd == conversion.REQ_CMD_CONNECT:
self._logger.info("TCP req to %s:%d support it. Returning HOST UNREACHABLE",
*request.destination)
response = conversion.encode_reply(0x05, conversion.REP_HOST_UNREACHABLE, 0x00,
conversion.ADDRESS_TYPE_IPV4, "0.0.0.0", 0)
self.transport.write(response)
else:
self.deny_request(request, "CMD not recognized")
except:
response = conversion.encode_reply(0x05, conversion.REP_COMMAND_NOT_SUPPORTED, 0x00,
conversion.ADDRESS_TYPE_IPV4, "0.0.0.0", 0)
self.transport.write(response)
self._logger.exception("Exception thrown, returning unsupported command response")
return True
def deny_request(self, request, reason):
"""
Deny SOCKS5 request
@param Request request: the request to deny
"""
self.state = ConnectionState.CONNECTED
response = conversion.encode_reply(0x05, conversion.REP_COMMAND_NOT_SUPPORTED, 0x00,
conversion.ADDRESS_TYPE_IPV4, "0.0.0.0", 0)
self.transport.write(response)
self._logger.error("DENYING SOCKS5 request, reason: %s" % reason)
def on_udp_associate_request(self, connection, request):
# The DST.ADDR and DST.PORT fields contain the address and port that the client expects
# to use to send UDP datagrams on for the association. The server MAY use this information
# to limit access to the association.
self._udp_socket = SocksUDPConnection(self, request.destination)
ip = self.transport.getHost().host
port = self._udp_socket.get_listen_port()
self._logger.info("Accepting UDP ASSOCIATE request to %s:%d", ip, port)
response = conversion.encode_reply(0x05, conversion.REP_SUCCEEDED,
0x00, conversion.ADDRESS_TYPE_IPV4,
ip, port)
self.transport.write(response)
def on_udp_associate_request(self, connection, request):
if self.selection_strategy.has_options(self.hops):
# The DST.ADDR and DST.PORT fields contain the address and port that the client expects
# to use to send UDP datagrams on for the association. The server MAY use this information
# to limit access to the association.
self._udp_socket = SocksUDPConnection(self, request.destination)
ip = self.transport.getHost().host
port = self._udp_socket.get_listen_port()
self._logger.info("Accepting UDP ASSOCIATE request to %s:%d", ip, port)
response = conversion.encode_reply(
0x05, conversion.REP_SUCCEEDED, 0x00, conversion.ADDRESS_TYPE_IPV4, ip, port)
self.transport.write(response)
else:
reason = "not enough circuits"
self.deny_request(request, reason)
self.close(reason)
