端口映射（socket应用）

# coding=gb2312
 
import sys
import time
import socket
import thread
import subprocess
 
################################
 
interfaceName = "本地连接"
portStart = 10000
portNumber = 500
 
################################
 
def getNextIp(ip):
    t = [int(x) for x in ip.split(".")]
    assert len(t) == 4
    t[3] += 1
    for i in range(3, -1, -1):
        if t[i] > 255:
            assert i > 0
            t[i] = 1
            t[i - 1] += 1
        else:
            break
    return ".".join([str(x) for x in t])
 
def print_with_lock(msg):
    lock.acquire()
    print msg
    lock.release()
 
def server(listen_host, listen_port, target_host, target_port):
    print_with_lock("server started, %s, %s, %s, %s" % (listen_host, listen_port, target_host, target_port))
    try:
        dock_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        dock_socket.bind((listen_host, listen_port))
        dock_socket.listen(5)
        while True:
            client_socket, client_address = dock_socket.accept()
            print_with_lock("connection accepted, %s, %s, %s, %s" % (listen_host, listen_port, target_host, target_port))
            server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
            server_socket.connect((target_host, target_port))
            thread.start_new_thread(forward, (client_socket, server_socket, "client -> server" ))
            thread.start_new_thread(forward, (server_socket, client_socket, "server -> client" ))
    finally:
        thread.start_new_thread(server, (listen_host, listen_port, target_host, target_port))
 
def forward(source, destination, description):
    data = 'dummy'
    while data:
        data = source.recv(1024)
        if data:
            destination.sendall(data)
        else:
            source.shutdown(socket.SHUT_RD)
            destination.shutdown(socket.SHUT_WR)
 
lock = thread.allocate_lock()
 
# 启动代理线程
port = portStart
ipin = "127.0.0.2"
for i in range(0, portNumber):
    thread.start_new_thread(server, ("0.0.0.0", port, ipin, 23))
    ipin = getNextIp(ipin)
    port += 1
 
while True:
    time.sleep(1.0)