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。
