【发布时间】：2018-05-20 06:03:43
【问题描述】：
我正在尝试构建一个发送和接收数据的 TCP 代理脚本，我设法让它监听，但它似乎没有正确连接......我的代码在我看来是正确的，在检查了 python 之后docs（我正在尝试在 python 2.7 和 3.6 中运行它）我收到此超时消息：
输出：
anon@kali:~/Desktop/python scripts$ sudo python TCP\ proxy.py 127.0.0.1 21 ftp.target.ca 21 True
[*] Listening on 127.0.0.1:21d
[==>] Received incoming connection from 127.0.0.1:44806d
Exception in thread Thread-1:
Traceback (most recent call last):
File "/usr/lib/python2.7/threading.py", line 801, in __bootstrap_inner
self.run()
File "/usr/lib/python2.7/threading.py", line 754, in run
self.__target(*self.__args, **self.__kwargs)
File "TCP proxy.py", line 60, in proxy_handler
remote_socket.connect((remote_host,remote_port))
File "/usr/lib/python2.7/socket.py", line 228, in meth
return getattr(self._sock,name)(*args)
error: [Errno 110] Connection timed out
我查看了文件“/usr/lib/python2.7/socket.py”，但无法真正理解我在寻找什么，因为当我将它与 python 文档和我的脚本进行比较时，它似乎是正确的
我的代码：
# import the modules
import sys
import socket
import threading
#define the server
def server_loop(local_host,local_port,remote_host,remote_port,receive_first):
server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
try:
server.bind((local_host, local_port))
server.listen(5)
print ("[*] Listening on %s:%sd" % (local_host, local_port))
except:
print("[!!] Failed to listen on %s:%sd" % (local_host,local_port))
print ("[!!] Check for others listening sockets or correct permissions")
sys.exit(0)
while True:
client_socket, addr = server.accept()
#print out the local connection information
print ("[==>] Received incoming connection from %s:%sd" % (addr[0],addr[1]))
#start a thread to talk to the remote host
proxy_thread = threading.Thread(target=proxy_handler,args=(client_socket,remote_host,remote_port,receive_first))
proxy_thread.start()
else:
print ("something went wrong")
def main():
#no fancy command-line parasing here
if len(sys.argv[1:]) !=5:
print ("Usage: ./TCP proxy.py [localhost] [localport] [remotehost] [remoteport] [receive_first]")
print("Example: ./TCP proxy.py 127.0.0.1 9000 10.12.132.1 9000 True")
#set up local listening parameters
local_host = sys.argv[1]
local_port = int(sys.argv[2])
#set up remote target
remote_host = sys.argv[3]
remote_port = int(sys.argv[4])
#this tells proxy to connect and receive data before sending to remote host
receive_first = sys.argv[5]
if "True" in receive_first:
receive_first = True
else:
receive_first = False
#now spin up our listening socket
server_loop(local_host,local_port,remote_host,remote_port,receive_first)
def proxy_handler(client_socket, remote_host, remote_port, receive_first):
#connect to the remote host
remote_socket = socket.socket(socket.AF_INET,socket.SOCK_STREAM)
remote_socket.connect((remote_host,remote_port))
#receive data from the remote end if necessary
if receive_first:
remote_buffer = receive_from(remote_socket)
hexdump(remote_buffer)
#send it to the repsonse handler
remote_buffer = respsonse_handler(remote_buffer)
#if data is able to be sent to local client, send it
if len(remote_buffer):
print ("[<==] Sending %d bytes to localhost." % len(remote_buffer))
client_socket.send(remote_buffer)
#now loop and read from local,sent to remote,send to local,rinse/wash/repeat
while True:
#read from local host
local_buffer = receive_from(client_socket)
if len(local_buffer):
print ("[==>] Received %d bytes from localhost." % len(local_buffer))
#send it to request handler
local_buffer = request_handler(local_buffer)
#send data to remote host
remote_socket.send(local_buffer)
print ("[==>] Sent to remote.")
#receive back response
remote_buffer = receive_from(remote_socket)
if len(remote_buffer):
print ("[<==] Received %d bytes from remote." % len(remote_buffer))
hexdump(remote_buffer)
#send response to handler
remote_buffer = response_handler(remote_buffer)
#send response to local socket
client_socket.send(remote_buffer)
print ("[<==] Sent to localhost.")
#if no data left on either side, close connection
if not len(local_buffer) or not len(remote_buffer):
client_socket.close()
remote_socket.close()
print ("[*] No more data, closing connections.")
break
#this is a pretty hex dumping function taken from the comments of http://code.activestate.com/recipes/142812-hex-dumper/
def hexdump(src, length=16):
result = []
digits = 4 if isinstance(src,unicode) else 2
for i in xrange(0,len(src), length):
s = src[i:i+length]
hexa = b' '.join(["%0*X" % (digits, ord(x)) for x in s])
text = b' '.join([x if 0x20 <= ord(x) < 0x7F else b'.' for x in s])
result.append( b"%04X %-*s %s" % (i, length*(digits + 1), hexa, text) )
print (b'/n'.join(result))
def receive_from(connection):
buffer = ""
#set a 2 second timeout; depending on your target this may need to be adjusted
connection.settimeout(2)
try:
#keep reading the buffer until no more data is there or it times out
while True:
data = connection.recv(4096)
if not data:
break
buffer += data
except:
pass
return buffer
#modify any requested destined for the remote host
def request_handler(buffer):
#perform packet modifications
return buffer
#modify any responses destined for the local host
def response_handler(buffer):
#perform packet modifications
return buffer
main()
我尝试了不同的 ftp 服务器/站点等，但得到了相同的结果，我的代码哪里出错了？任何意见或方向将不胜感激。
【问题讨论】：
标签： python python-3.x python-2.7 tcp proxy