#!/usr/bin/python

This is a simple port-forward / proxy, written using only the default python

library. If you want to make a suggestion or fix something you can contact-me

at voorloop_at_gmail.com

Distributed over IDC(I Don't Care) license

import socket import select import time import sys

Changing the buffer_size and delay, you can improve the speed and bandwidth.

But when buffer get to high or delay go too down, you can broke things

buffer_size = 4096 delay = 0.0001 forward_to = ('smtp.zaz.ufsk.br', 25)

class Forward: def init(self): self.forward = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

def start(self, host, port):
    try:
        self.forward.connect((host, port))
        return self.forward
    except Exception, e:
        print e
        return False

class TheServer: input_list = [] channel = {}

def __init__(self, host, port):
    self.server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    self.server.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
    self.server.bind((host, port))
    self.server.listen(200)

def main_loop(self):
    self.input_list.append(self.server)
    while 1:
        time.sleep(delay)
        ss = select.select
        inputready, outputready, exceptready = ss(self.input_list, [], [])
        for self.s in inputready:
            if self.s == self.server:
                self.on_accept()
                break

            self.data = self.s.recv(buffer_size)
            if len(self.data) == 0:
                self.on_close()
                break
            else:
                self.on_recv()

def on_accept(self):
    forward = Forward().start(forward_to[0], forward_to[1])
    clientsock, clientaddr = self.server.accept()
    if forward:
        print clientaddr, "has connected"
        self.input_list.append(clientsock)
        self.input_list.append(forward)
        self.channel[clientsock] = forward
        self.channel[forward] = clientsock
    else:
        print "Can't establish connection with remote server.",
        print "Closing connection with client side", clientaddr
        clientsock.close()

def on_close(self):
    print self.s.getpeername(), "has disconnected"
    #remove objects from input_list
    self.input_list.remove(self.s)
    self.input_list.remove(self.channel[self.s])
    out = self.channel[self.s]
    # close the connection with client
    self.channel[out].close()  # equivalent to do self.s.close()
    # close the connection with remote server
    self.channel[self.s].close()
    # delete both objects from channel dict
    del self.channel[out]
    del self.channel[self.s]

def on_recv(self):
    data = self.data
    # here we can parse and/or modify the data before send forward
    print data
    self.channel[self.s].send(data)

if name == 'main': server = TheServer('', 9090) try: server.main_loop() except KeyboardInterrupt: print "Ctrl C - Stopping server" sys.exit(1)