tracing pf code

[Max Laier]

On Wednesday 15 October 2008 02:47:46 alan yang wrote:
> hello,
>
> for pf port on freebsd, i would like to trace the packet flow, looking
> at from ether_input -> etiher_demux -> ip_input -> tcp_input where /
> how pf handles / process the packet.
>
> can people shed some lights where to start.  really appreciate.

ps hooks into the pfil(9) hook point in ip[6]_{in,out}put().  Look for calls 
to "pfil_run_hooks" in the code.  From there the call proceeds to the hook 
functions defined in pf_ioctl.c pf_check_{in,out}[6].

The processing inside pf is best understood by looking at the following chart: 
http://homepage.mac.com/quension/pf/flow.png

Is this the information you are looking for?

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