On Tue, 27 Nov 2001, Hemant Puri wrote:
> I want to use NetBSD as a router and want to capture/modify the TCP
> packets going out. (Something like a firewall functionality with the
> additional ability to modify packets).
> 
> Any pointers on how it can be done would be appreciated.

Check out the IPfilter Firewall code that comes with NetBSD, it's located
somewhere in /sys. IPfilter uses the packet filter interface, which might
be of interrest too, it's enabled with the kernel option PFIL_HOOKS and
documented in the pfil(9) manpage. There's also the bpf(4) interface that
might be interresting.


 - Hubert (NOT a kernel guru!)

-- 
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* Basics -> http://www.onlamp.com/pub/a/onlamp/2001/05/24/ipv6_tutorial.html
* Setup  -> http://www.onlamp.com/pub/a/onlamp/2001/06/01/ipv6_tutorial.html 
Of course with your #1 IPv6 ready operating system -> http://www.NetBSD.org/