本文實例講述了python實現簡單的TCP代理服務器的方法，分享給大家供大家參考。

具體實現代碼如下：

# -*- coding: utf-8 -*-'''filename:rtcp.py@desc:利用python的socket端口轉發，用于遠程維護如果連接不到遠程，會sleep 36s，最多嘗試200(即兩小時)@usage:./rtcp.py stream1 stream2stream為：l:port或c:host:portl:port表示監聽指定的本地端口c:host:port表示監聽遠程指定的端口@author: watercloud, zd, knownsec team@web: www.knownsec.com, blog.knownsec.com@date: 2009-7'''import socketimport sysimport threadingimport timestreams = [None, None] # 存放需要進行數據轉發的兩個數據流（都是SocketObj對象）debug = 1 # 調試狀態 0 or 1def _usage(): print 'Usage: ./rtcp.py stream1 stream2/nstream : l:port or c:host:port'def _get_another_stream(num): ''' 從streams獲取另外一個流對象，如果當前為空，則等待 ''' if num == 0: num = 1 elif num == 1: num = 0 else: raise "ERROR" while True: if streams[num] == 'quit':  print("can't connect to the target, quit now!")  sys.exit(1) if streams[num] != None:  return streams[num] else:  time.sleep(1)def _xstream(num, s1, s2): ''' 交換兩個流的數據 num為當前流編號,主要用于調試目的，區分兩個回路狀態用。 ''' try: while True:  #注意，recv函數會阻塞，直到對端完全關閉（close后還需要一定時間才能關閉，最快關閉方法是shutdow）  buff = s1.recv(1024)  if debug > 0:  print num,"recv"  if len(buff) == 0: #對端關閉連接，讀不到數據  print num,"one closed"  break  s2.sendall(buff)  if debug > 0:  print num,"sendall" except : print num,"one connect closed." try: s1.shutdown(socket.SHUT_RDWR) s1.close() except: pass try: s2.shutdown(socket.SHUT_RDWR) s2.close() except: pass streams[0] = None streams[1] = None print num, "CLOSED"def _server(port, num): ''' 處理服務情況,num為流編號（第0號還是第1號） ''' srv = socket.socket(socket.AF_INET, socket.SOCK_STREAM) srv.bind(('0.0.0.0', port)) srv.listen(1) while True: conn, addr = srv.accept() print "connected from:", addr streams[num] = conn # 放入本端流對象 s2 = _get_another_stream(num) # 獲取另一端流對象 _xstream(num, conn, s2)def _connect(host, port, num): ''' 處理連接，num為流編號（第0號還是第1號） @note: 如果連接不到遠程，會sleep 36s，最多嘗試200(即兩小時) ''' not_connet_time = 0 wait_time = 36 try_cnt = 199 while True: if not_connet_time > try_cnt:  streams[num] = 'quit'  print('not connected')  return None conn = socket.socket(socket.AF_INET, socket.SOCK_STREAM) try:  conn.connect((host, port)) except Exception, e:  print ('can not connect %s:%s!' % (host, port))  not_connet_time += 1  time.sleep(wait_time)  continue print "connected to %s:%i" % (host, port) streams[num] = conn #放入本端流對象 s2 = _get_another_stream(num) #獲取另一端流對象 _xstream(num, conn, s2)if __name__ == '__main__': if len(sys.argv) != 3: _usage() sys.exit(1) tlist = [] # 線程列表，最終存放兩個線程對象 targv = [sys.argv[1], sys.argv[2] ] for i in [0, 1]: s = targv[i] # stream描述 c:ip:port 或 l:port sl = s.split(':') if len(sl) == 2 and (sl[0] == 'l' or sl[0] == 'L'): # l:port  t = threading.Thread(target=_server, args=(int(sl[1]), i))  tlist.append(t) elif len(sl) == 3 and (sl[0] == 'c' or sl[0] == 'C'): # c:host:port  t = threading.Thread(target=_connect, args=(sl[1], int(sl[2]), i))  tlist.append(t) else:  _usage()  sys.exit(1) for t in tlist: t.start() for t in tlist: t.join() sys.exit(0)