python实现端口转发器的方法

本文实例讲述了python实现端口转发器的方法。分享给大家供大家参考。具体如下：

下面的python代码实现端口转发器，支持udp端口转发

由于工作需要用到一个端口转发器，并且要求支持TCP和UDP协议。在网上找了蛮久，但没有中意的。于是就自己写了一个。这个转发器是基于python cookbook的一个示例改写的，原先的这个示例只支持TCP协议，我这里增加了UDP协议的支持，程序写的不怎么好，不过它确实能用！

portmap.py代码如下：

#-* -coding: UTF-8 -* -

'''

Created on 2012-5-8

@author: qh

'''

import time,socket,threading

def log(strLog):

    strs=time.strftime("%Y-%m-%d %H:%M:%S")

    print strs+"->"+strLog

class pipethread(threading.Thread):

    '''

    classdocs

    '''

    def __init__(self,source,sink):

        '''

        Constructor

        '''

        threading.Thread.__init__(self)

        self.source=source

        self.sink=sink

        log("New Pipe create:%s->%s" % (self.source.getpeername(),self.sink.getpeername()))

    def run(self):

        while True:

            try:

                data=self.source.recv(1024)

                if not data: break

                self.sink.send(data)

            except Exception ,ex:

                log("redirect error:"+str(ex))

                break

        self.source.close()

        self.sink.close()

class portmap(threading.Thread):

    def __init__(self,port,newhost,newport,local_ip=''):

        threading.Thread.__init__(self)

        self.newhost=newhost

        self.newport=newport

        self.port=port

        self.local_ip=local_ip

        self.sock=None

        self.sock=socket.socket(socket.AF_INET,socket.SOCK_STREAM)

        self.sock.bind((self.local_ip,port))

        self.sock.listen(5)

        log("start listen protocol:%s,port:%d " % ('tcp',port))

    def run(self):

        while True:

            fwd=None

            newsock=None

            newsock,address=self.sock.accept()

            log("new connection->protocol:%s,local port:%d,remote address:%s" % ('tcp',self.port,address[0]))

            fwd=socket.socket(socket.AF_INET,socket.SOCK_STREAM)

            try:

                fwd.connect((self.newhost,self.newport))

            except Exception ,ex:

                log("connet newhost error:"+str(ex))

                break

            p1=pipethread(newsock,fwd,self.protocol)

            p1.start()

            p2=pipethread(fwd,newsock,self.protocol)

            p2.start()

class pipethreadUDP(threading.Thread):

    def __init__(self,connection,connectionTable,table_lock):

        threading.Thread.__init__(self)

        self.connection=connection

        self.connectionTable=connectionTable

        self.table_lock=table_lock

        log('new thread for new connction')

    def run(self):

        while True:

            try:

                data,addr=self.connection['socket'].recvfrom(4096)

                #log('recv from addr"%s' % str(addr))

            except Exception ,ex:

                log("recvfrom error:"+str(ex))

                break

            try:

                self.connection['lock'].acquire()

                self.connection['Serversocket'].sendto(data,self.connection['address'])

                #log('sendto address:%s' % str(self.connection['address']))

            except Exception ,ex:

                log("sendto error:"+str(ex))

                break

            finally:self.connection['lock'].release()

            self.connection['time']=time.time()

        self.connection['socket'].close()

        log("thread exit for: %s" % str(self.connection['address']))

        self.table_lock.acquire()

        self.connectionTable.pop(self.connection['address'])

        self.table_lock.release()

        log('Release udp connection for timeout:%s' % str(self.connection['address']))

class portmapUDP(threading.Thread):

    def __init__(self,port,newhost,newport,local_ip=''):

        threading.Thread.__init__(self)

        self.newhost=newhost

        self.newport=newport

        self.port=port

        self.local_ip=local_ip

        self.sock=socket.socket(socket.AF_INET,socket.SOCK_DGRAM)

        self.sock.bind((self.local_ip,port))

        self.connetcTable={}

        self.port_lock=threading.Lock()

        self.table_lock=threading.Lock()

        self.timeout=300

        #ScanUDP(self.connetcTable,self.table_lock).start()

        log('udp port redirect run->local_ip:%s,local_port:%d,remote_ip:%s,remote_port:%d' % (local_ip,port,newhost,newport))

    def run(self):

        while True:

            data,addr=self.sock.recvfrom(4096)

            connection=None

            newsock=None

            self.table_lock.acquire()

            connection=self.connetcTable.get(addr)

            newconn=False

            if connection is None:

                connection={}

                connection['address']=addr

                newsock=socket.socket(socket.AF_INET,socket.SOCK_DGRAM)

                newsock.settimeout(self.timeout)

                connection['socket']=newsock

                connection['lock']=self.port_lock

                connection['Serversocket']=self.sock

                connection['time']=time.time()

                newconn=True

                log('new connection:%s' % str(addr))

            self.table_lock.release()

            try:

                connection['socket'].sendto(data,(self.newhost,self.newport))

            except Exception ,ex:

                log("sendto error:"+str(ex))

                #break

            if newconn:

                self.connetcTable[addr]=connection

                t1=pipethreadUDP(connection,self.connetcTable,self.table_lock)

                t1.start()

        log('main thread exit')

        for key in self.connetcTable.keys():

            self.connetcTable[key]['socket'].close()

if __name__=='__main__':

    myp=portmapUDP(10061,'10.0.1.29',161)

    myp.start()

    #myp.__stop()

希望本文所述对大家的Python程序设计有所帮助。