how to create a linux kernel module that intercepts outgoingIP packets

[Mohamedali]

hi all,

I am currently working in the compression of IP header packets
I use a library which is called RoHC ( Robust Header Compression)

well, I want to create a 2.6 Linux kernel module that inetercepts outgoing packets in order to compress them using RoHC and then resent them


Please anybody can help me or send me a source code of kernel module which intercepts IP packets ??
I can't find many things in nthe net about how to proceed !!
I hope you can help me
my email is medaliziedi(at)hotmail.com

Thanks a lot
Regards

[Rubberman]

IPv4 or IPv6? You can find this stuff in the kernel source/net/ipv4 or ipv6 directories.

[Mohamedali]

Thanks Rubberman for response,
In fact i Want to compress an IPv6 header packet
I used RoHC library ( see launchpad.net/rohc ) and it works well but it works only in userland
so i need to convert all its code to a kernel code
that 's why i want to know how to proceed to create a kernel module that intercepts outgoing packets and uses the RoHC ( after being transformed into kernel)
any help ??
regards

[Rubberman]

It's possible, but not trivial. You really should read up on kernel module programming before you start. The O'Reilly book "Linux Device Drivers, 3rd Edition" - it's available freely online. Here is a link to the PDF: http://www.davehylands.com/Misc/Linu...rd-Edition.pdf

or here: Linux Device Drivers, Third Edition [LWN.net]

[Mohamedali]

Thanksssss Robberman for your help !!!

[nplusplus]

You might also check out the Netfilter/Iptables project.

netfilter/iptables project homepage - The netfilter.org project