http://bt3gl.github.io/black-hat-python-infinite-possibilities-with-the-scapy-module.html 

 Black Hat Python: Infinite possibilities with the Scapy Module

Mon 22 December 2014 Category Networking Tags Python scapy Book traceroute PCAP ARP_poisining sniffing Wireshark packet_header

This is a review about one of my favorites libraries in Python: Scapy, which is a very powerful packet manipulation resource.
Scapy is able to forge and decode packets of several protocols, send and capture them, match requests and replies, and much more. It can be used to handle most network tasks such as scanning, tracerouting, probing, attacks, network discovery, to name a few.
Before we start, make sure you have Scapy in your machine:

$ pip install scapy

You can test the installation firing up Scapy iteratively. For example, these are some useful functions:

$ scapy
Welcome to Scapy (2.2.0)
>>> ls()    ---> list protocols/layers
>>> lsc()   ---> list commands
>>> conf    ---> Display configurations
>>> help(sniff)     --> Help for a specific command

This post is divided as the following:

• Scapy 101 (including sniffing, scanning, fuzzing,...),
• Stealing Plain Text Email Data,
• ARP Poisoning a Machine, and
• Processing PCAP Files.