From owner-freebsd-net  Thu Jun 27 16:40:18 2002
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Date: Thu, 27 Jun 2002 16:20:52 -0700 (PDT)
From: Julian Elischer <julian@elischer.org>
To: Arthur Peet <arthur.peet@toltec.biz>
Cc: freebsd-net@FreeBSD.ORG
Subject: Re: bpf/netgraph interaction
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Ipfw divers from within the IP stack
by then it's too late.

you could diver th epackets using netgraph and filter them and then 
pass them back into the eiface netgraph node to continue up.

then you tell your application to listen to the "nge"
interface.. unfortunatly another driver also produces 'nge' interfaces,
but the chance you have htat card is quite small.



[fxp0]<--->[ng_ether]<----->{filter}<--->ng_eiface<---->[IP stack]
                                            \
                                             \---BPF







On Thu, 27 Jun 2002, Arthur Peet wrote:

> At 04:50 PM 6/27/2002, Julian Elischer wrote:
> > > Are there any other taps I may access in order to accomplish this goal?
> >
> >I forget the goal. sorry
> 
> 
> 
> No problem - Hope you don't mind if I restate it.
> I am trying to strip/drop packets before they reach a server process which uses
> BPF for communicating with the network interface.
> I have briefly been looking into using an ipfw/divert socket, but I don't 
> think that is
> going to work either.
> 
> Thanks again!
> -Art
> 
> 
> 
> 
> 
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