TCP: bind the IP which connecting in, or set the IP by config file

allow setting method/bind/bindv6 for each port

shadowsocks/server.py

@@ -65,10 +65,13 @@ def main():
     config_password = config.get('password', 'm')
     del config['port_password']
     for port, password_obfs in port_password.items():
+        method = config["method"]
         protocol = config.get("protocol", 'origin')
         protocol_param = config.get("protocol_param", '')
         obfs = config.get("obfs", 'plain')
         obfs_param = config.get("obfs_param", '')
+        bind = config.get("bind", '')
+        bindv6 = config.get("bindv6", '')
         if type(password_obfs) == list:
             password = password_obfs[0]
             obfs = password_obfs[1]
@@ -76,10 +79,13 @@ def main():
                 protocol = password_obfs[2]
         elif type(password_obfs) == dict:
             password = password_obfs.get('password', config_password)
+            method = password_obfs.get('method', method)
             protocol = password_obfs.get('protocol', protocol)
             protocol_param = password_obfs.get('protocol_param', protocol_param)
             obfs = password_obfs.get('obfs', obfs)
             obfs_param = password_obfs.get('obfs_param', obfs_param)
+            bind = password_obfs.get('bind', bind)
+            bindv6 = password_obfs.get('bindv6', bindv6)
         else:
             password = password_obfs
         a_config = config.copy()
@@ -92,10 +98,13 @@ def main():
                     a_config['server_ipv6'] = a_config['server_ipv6'][1:-1]
                 a_config['server_port'] = int(port)
                 a_config['password'] = password
+                a_config['method'] = method
                 a_config['protocol'] = protocol
                 a_config['protocol_param'] = protocol_param
                 a_config['obfs'] = obfs
                 a_config['obfs_param'] = obfs_param
+                a_config['bind'] = bind
+                a_config['bindv6'] = bindv6
                 a_config['server'] = a_config['server_ipv6']
                 logging.info("starting server at [%s]:%d" %
                              (a_config['server'], int(port)))
@@ -110,10 +119,13 @@ def main():
             a_config = config.copy()
             a_config['server_port'] = int(port)
             a_config['password'] = password
+            a_config['method'] = method
             a_config['protocol'] = protocol
             a_config['protocol_param'] = protocol_param
             a_config['obfs'] = obfs
             a_config['obfs_param'] = obfs_param
+            a_config['bind'] = bind
+            a_config['bindv6'] = bindv6
             logging.info("starting server at %s:%d" %
                          (a_config['server'], int(port)))
             tcp_servers.append(tcprelay.TCPRelay(a_config, dns_resolver, False))

shadowsocks/tcprelay.py

@@ -138,6 +138,8 @@ class TCPRelayHandler(object):
         self._protocol.set_server_info(server_info)
 
         self._redir_list = config.get('redirect', ["0.0.0.0:0"])
+        self._bind = config.get('bind', '')
+        self._bindv6 = config.get('bindv6', '')
 
         self._fastopen_connected = False
         self._data_to_write_to_local = []
@@ -516,6 +518,20 @@ class TCPRelayHandler(object):
             remote_sock_v6.setblocking(False)
         else:
             remote_sock.setsockopt(socket.SOL_TCP, socket.TCP_NODELAY, 1)
+            if not self._is_local:
+                bind_addr = ''
+                if self._bind and af == socket.AF_INET:
+                    bind_addr = self._bind
+                elif self._bindv6 and af == socket.AF_INET:
+                    bind_addr = self._bindv6
+                else:
+                    bind_addr = self._local_sock.getsockname()[0]
+
+                bind_addr = bind_addr.replace("::ffff:", "")
+                local_addrs = socket.getaddrinfo(bind_addr, port, 0, socket.SOCK_STREAM, socket.SOL_TCP)
+                if local_addrs[0][0] == af:
+                    logging.debug("bind %s" % (bind_addr,))
+                    remote_sock.bind((bind_addr, 0))
         return remote_sock
 
     def _handle_dns_resolved(self, result, error):