Is there a Python library than can simulate network traffic from different addresses

Question

Is there a python library out there than can allow me to send UDP packets to a machine (sending to localhost is ok) from different source addresses and ports? I remember that one existed, but can't find it anymore.

Answer 1

You can spoof an IP address using Scapy library.

Here's an example from Packet Wizardry: Ruling the Network with Python:

  #!/usr/bin/env python
  import sys
  from scapy import *
  conf.verb=0

  if len(sys.argv) != 4:
      print "Usage: ./spoof.py <target> <spoofed_ip> <port>"
      sys.exit(1)

  target = sys.argv[1]
  spoofed_ip = sys.argv[2]
  port = int(sys.argv[3])

  p1=IP(dst=target,src=spoofed_ip)/TCP(dport=port,sport=5000,flags='S')
  send(p1)
  print "Okay, SYN sent. Enter the sniffed sequence number now: "

  seq=sys.stdin.readline()
  print "Okay, using sequence number " + seq

  seq=int(seq[:-1])
  p2=IP(dst=target,src=spoofed_ip)/TCP(dport=port,sport=5000,flags='A',
                                       ack=seq+1,seq=1)
  send(p2)

  print "Okay, final ACK sent. Check netstat on your target :-)"