Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 27 Jun 2001 16:42:45 -0700
From:      Stuart Eichert <seichert@coopcomp.com>
To:        net@freebsd.org
Subject:   Re: Am I missing something?
Message-ID:  <20010627164245.B48973@gourdy.coopcomp.com>

next in thread | raw e-mail | index | archive | help
On Wed, Jun 27, 2001 at 02:30:42PM -0500, Alfred Perlstein wrote:
<snip, my old comment>
> Why not provide a patch that allows one to add callbacks to the list?
> 
> for ether_output under the default case you would walk the list
> looking for your type, since for the most part packets will be in
> AF_INET and when no callbacks are registered the array will be
> short, transmit should be cheap.  For recieve if you look in
> the default case you can see ng_ether_input_orphan_p being used to
> input packets that don't match a known type.

	It was my feeling that a good idea might be to set aside a
range of ETHERTYPEs for research/testing use.  Put them after the normal ones,
so that AF_INET and others will get checked for first (thus hopefully not
harming performance for the normal case).  The last case statement could be
something that sees if the type is in the research range, and then if it
is it could do some sort of lookup in a hash table/cache deal and then
call the appropriate callback funcs.  

	My goal for this project is to not only provide code for adding a
network protocol to FreeBSD, but also document the process so that others
can learn how to modify the network subsystem.  In addition I would like to
provide a framework for people to dynamically add and remove new protocols.
If I was able to patch if_ethersubr (and probably a few others) to allow for
these dynamically available protocols, what are the chances that the code
would be committed and become part of FreeBSD 4.4 or 5.0?  The reason I ask
is that I would like to reduce the barriers to people using FreeBSD for this
purpose.  I would like to say to them "Hey install FreeBSD 4.4 with default
settings, nothing special, download a few of these network protocol modules,
load them, try the test apps"  After they do that, hopefully they will
read the documents about how to add protocols to FreeBSD, or at least use
of the tools/libs I provide to add their own protocols.  The intended market
is researchers who may or may not currently use FreeBSD in their research.

-- 
------------
Stuart Eichert
Cooperative Computers, Inc.
seichert@coopcomp.com
(650)938-0730 x 15


----- End forwarded message -----

-- 
------------
Stuart Eichert
Cooperative Computers, Inc.
seichert@coopcomp.com
(650)938-0730 x 15


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-net" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20010627164245.B48973>