IP Injection - This is raw stuff, human!

• Injecting IP packets is historically done using "raw sockets".
• These sockets work at the IP protocol level:
  1. They see everything (coming to the machine).
  2. They allow creating packets (at the IP protocol level).
  3. Two modes of operation:
     1. Mode I - we let the kernel form the IP header.
     2. Mode II - we form the entire IP header ourselves.

Originally written by guy keren