title: Python Scapy Intercept Packets before sending them on
body: <p>I have three virtual machines all on Centos 6.5. </p>
  
  <p>The current setup is as follows:</p>
  
  <p>A ------(eth0) B (eth1)------- C</p>
  
  <p>Currently, when A pings C, it is routed through B as they are on different networks.</p>
  
  <p>I want to write a script using python and scapy (Used on machine B) that will intercept the packet that passes through eth0.<br>
  By intercepting the packet, I can hold it for some time (delay) or do some packet manipulation. 
  I then want to send the packet to its destined destination.</p>
  
  <p>Does anyone know how I can intercept packets before they reach their end destination using Python and Scapy?</p>
  
  <p>I have read a lot about Netfilter and iptables but not exactly sure how I can intercept the packets and change them.</p>
  
  <p>Thank you in advance</p>