Tunneling TCP traffic over ICMP with Libnet

Good Morning,

I'm new to libnet programming and would like to see if I've picked the appropriate tool for the task at hand. I would like to demonstrate the ability to send traffic (ASCII, file xfers, etc.) into a "secured" (lab) network using NetCat and an ICMP tunnel (ttl-exceeded or echo-reply). I have taken a look at icmptunnel (http://www.detached.net/icmptunnel/ ), but am looking to program one from scratch. Here's what I had in mind:

Server Side:
./tunnel y.y.y.y | nc -l -p 12345

Client Side:
nc x.x.x.x 12345 | ./tunnel x.x.x.x

So basically, I would like to be able to pipe packets from NetCat into the application and on the Client side, have it encapsulate the original datagram within the ICMP packet, sending it to the server. At the server, I would like to have it extract the payload (original TCP packet) and pass it to NetCat on the other side where it can be interpreted.

It appears that libnet allows this type of packet manipulation. Let me know what you think. And thanks for taking the time to take a look at this!

-Jeremy