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Date: Fri, 23 Aug 1996 15:57:33 -0500
To: Paul Traina <pst@jnx.com>
From: rkw@dataplex.net (Richard Wackerbarth)
Subject: Re: cvs commit: src/sys/netinet in.h ip_fw.h ip_input.c ip_output.c
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In response to the idea:
>  > for the hook should be something like:
>  >
>  >     for (hook = iphooks.ipinput.lh_first; hook; hook = hook->next) {
>  >             if (!(*hook)(IP_INPUT, &m, &ip))
>  >                     break;
>  >     }

Terry Lamert asks:
>  Question: is there any particular reason this should be IP specific?

To which Paul Traina replys:
>Good point.  It saves re-doing a lot of work (e.g. protocol classification)
>if you do it in the IP stack, but there's nothing *forcing* it to be IP
>specific.

I suspect that Terry's point was that the hook mechanism need not be ip
specific. Rather, any communications stack, for example appletalk, could
use the same mechanism. I would anticipate that the filters would prefer to
do their "type checking" at registration time and only register for those
protocols that they are prepared to handle.