proxy.py

import sys
import socket
import threading

def proxy_handler(client_socket, remote_host, remote_port, receive_first):
    
    remote_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    remote_socket.connect((remote_host,remote_port))
    
    if receive_first:
        remote_buffer = receive_from(remote_socket)
        hexdump(remote_buffer)
        
        remote_buffer = response_handler(remote_buffer)
        
        if len(remote_buffer):
            print "[<==] Sending %d bytes to localhost." % len(remote_buffer)
            client_socket.send(remote_buffer)
            
        while True:
            
            local_buffer = receive_from(client_socket)
            
            if len(local_buffer):
                print "[==>] Received %d bytes from localhost." % len(local_buffer)
                hexdump(local_buffer)
                local_buffer = request_handler(local_buffer)
            
                remote_socket.send(local_buffer)
                print "[==>] Send to remote."
            remote_buffer = receive_from(remote_socket)
            
            if len(remote_buffer):
                print "[<==] Received %d bytes from remote." % len(remote_buffer)
                hexdump(remote_buffer)
                
                remote_buffer = response_handler(remote_buffer)
                
                client_socket.send(remote_buffer)
                
                print "[<==] Sent to localhost."
            if not len(local_buffer) or not len(remote_buffer):
                client_socket.close()
                remote_socket.close()
                print "[*] No more data. Closing connections."
                break
                
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, lenght*(digits + 1), hexa, text))
        
    print b'\n'.joi(result)
def receive_from(connection):
    
    buffer = ""
    
    connection.settimeout(2)
    
    try:
        while True:
            data = connection.recv(4096)
            if not data:
                break
            buffer += data
    except:
        pass
    return buffer
def request_handler(buffer):
    #change teh packets
    return buffer

def response_handler(buffer):
    #change the packets
    return buffer
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))
        
    except:
        print "[!!] Failed to listen on %s:%d" %(local_host,local_port)
        print "[!!] Check for other listening sockets or correct permissions."
        sys.exit(0)
        
    print "[*] Listening on %s:%d" % (local_host,local_port)
    
    server.listen(5)
    
    while True:
        client_socket, addr = server.accept()
        
        print "[==>] Received incoming connection from %s:%d" % (addr[0], addr[1])
        
        proxy_thread = threading.Thread(target = proxy_handler, args = \
        (client_socket, remote_host, remote_port,receive_first))
        
        proxy_thread.start()
        
def main():
        
    if len(sys.argv[1:])!=5:
        print "Usage: ./proxy.py [localhost] [localport] [remotehost] [remoteport] [receive_first]"
        print "Example: ./proxy.py 127.0.0.1 9000 10.12.132.1 9000 True"
        sys.exit(0)
            
    local_host = sys.argv[1]
    local_port = int(sys.argv[2])
        
    remote_host = sys.argv[3]
    remote_port = int(sys.argv[4])
        
    receive_first = sys.argv[5]
        
    if "True" in receive_first:
        receive_first = True
    else:
        receive_first = False
            
    server_loop(local_host,local_port,remote_host,remote_port,receive_first)
main()