cookinglinux

Happy kernel hacking !

Since I'm interested by the linux network stack, I raised some documents. It can be a good starting point in the studying of the linux stack.
If hacking at iptables/netfilter is interesting you too, you're at the right place. Here are some very good docs about it.

Netfilter

The links below are in a 'beginner to hacker' order. If you just got hooked into netfilter, consider following this order. There's probably some old docs, but they're still important to fully understand and assimilate the bases concepts.

ipchains: Packet Filtering for linux 2.2 Rusty Russell • Spring 1999
Fragments: Small Packets, Big Problems Rusty Russell • June 1999
Keeping the TCP/IP Stream Flowing Rusty Russell • August 1999
Anatomy Of A Patch Rusty Russell • September 1999
Beyond IPchains Rusty Russell • October 1999
Network Security With Linux 2.4 Rusty Russell •
Writing a Module for netfilter Rusty Russell • April 2000
Packet Filtering in the 2.4 Kernel Rusty Russell • September 2001
Netfilter Hacking Howto Rusty Russell and Harald Welte • July 2002
Netfilter connection tracking and nat helper modules Harald Welte • October 2000

Linux networking stack

Going further, it becomes very interesting to deeply understand how does the linux's networking stack work.

Packet Journey linux 2.4 Harald Welte • October 2000
eth dev init
init example
ip recv 1
ip recv 2
ip recv 3
ip rev 4
ip routing
NAPI
linux network subsystem
recv path
skb
sock include
udp recv