add udprelay

shadowsocks/udprelay.py

@@ -0,0 +1,117 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+
+# Copyright (c) 2014 clowwindy
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# SOCKS5 UDP Request
+# +----+------+------+----------+----------+----------+
+# |RSV | FRAG | ATYP | DST.ADDR | DST.PORT |   DATA   |
+# +----+------+------+----------+----------+----------+
+# | 2  |  1   |  1   | Variable |    2     | Variable |
+# +----+------+------+----------+----------+----------+
+
+# SOCKS5 UDP Response
+# +----+------+------+----------+----------+----------+
+# |RSV | FRAG | ATYP | DST.ADDR | DST.PORT |   DATA   |
+# +----+------+------+----------+----------+----------+
+# | 2  |  1   |  1   | Variable |    2     | Variable |
+# +----+------+------+----------+----------+----------+
+
+# shadowsocks UDP Request (before encrypted)
+# +------+----------+----------+----------+
+# | ATYP | DST.ADDR | DST.PORT |   DATA   |
+# +------+----------+----------+----------+
+# |  1   | Variable |    2     | Variable |
+# +------+----------+----------+----------+
+
+# shadowsocks UDP Response (before encrypted)
+# +------+----------+----------+----------+
+# | ATYP | DST.ADDR | DST.PORT |   DATA   |
+# +------+----------+----------+----------+
+# |  1   | Variable |    2     | Variable |
+# +------+----------+----------+----------+
+
+# shadowsocks UDP Request and Response (after encrypted)
+# +-------+--------------+
+# |   IV  |    PAYLOAD   |
+# +-------+--------------+
+# | Fixed |   Variable   |
+# +-------+--------------+
+
+# HOW TO NAME THINGS
+# ------------------
+# `dest`    means destination server, which is from DST fields in the SOCKS5
+#           request
+# `local`   means local server of shadowsocks
+# `remote`  means remote server of shadowsocks
+# `client`  means UDP clients that connects to other servers
+# `server`  means the UDP server that handle user requests
+
+
+import threading
+import socket
+import event
+
+
+class UDPRelay(object):
+    def __init__(self, listen_addr='127.0.0.1', listen_port=1080,
+                 remote_addr='127.0.0.1', remote_port=8387, password=None,
+                 method='table', timeout=300, is_local=True):
+        self._listen_addr = listen_addr
+        self._listen_port = listen_port
+        self._remote_addr = remote_addr
+        self._remote_port = remote_port
+        self._password = password
+        self._method = method
+        self._timeout = timeout
+        self._is_local = is_local
+        self._eventloop = event.EventLoop()
+
+    def _handle_server(self, addr, sock, data):
+        # TODO
+        pass
+
+    def _handle_client(self, addr, sock, data):
+        # TODO
+        pass
+
+    def _run(self):
+        eventloop = self._eventloop
+        server_socket = self._server_socket
+        eventloop.add_fd(server_socket, event.MODE_IN)
+        is_local = self._is_local
+        while True:
+            r = eventloop.poll()
+            # TODO
+
+    def start(self):
+        addrs = socket.getaddrinfo(self._listen_addr, self._listen_port, 0,
+                                   socket.SOCK_DGRAM, socket.SOL_UDP)
+        if len(addrs) == 0:
+            raise Exception("can't get addrinfo for %s:%d" %
+                            (self._listen_addr, self._listen_port))
+        af, socktype, proto, canonname, sa = addrs[0]
+        server_socket = socket.socket(af, socktype, proto)
+        server_socket.bind((self._listen_addr, self._listen_port))
+        server_socket.setblocking(False)
+        self._server_socket = server_socket
+
+        threading.Thread(target=self._run).start()