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From: Darren Reed <avalon@coombs.anu.edu.au>
Subject: DIVERT
To: julian@whistle.com (Julian Elischer)
Date: Thu, 15 Aug 1996 20:23:57 +1000 (EST)
Cc: hackers@FreeBSD.ORG
In-Reply-To: <32129D22.2C67412E@whistle.com> from "Julian Elischer" at Aug 14, 96 08:44:34 pm
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In some mail from Julian Elischer, sie said:
> 
> No, that isn't quite what divert does..
> divert is a bit more powerful than that
> it uses a divert socket type to pass the packets up to the user.
> this allows other info to be passed as well..
> the main difference is that you can using the divert socket, re-inject the
> packet back at the point that it was taken out, and control to a greater
> extent what happens to it..
> 
> divert sockets are an experiment which may or may not survive
> but we have found that they allow us to do things that we couldn't do
> using the tunnel interface.
> 
> firstly sockets are inherrently packet oriented, so you can do
> 'sendto' on them for example to give different sematics to what
> happens to the packet after re-injection.
> 
> there are other problems that are solved by this approach.
> we looked at tun interfaces and decided that it was banging a square
> peg into a round hole.

What was/is the aim of it ?

To me it sounds a lot like what screend does, except there is a way to
open multiple instances for intercepting packets.

Although, I don't quite see how they fit in to the operational scheme of
things.

> each divert socket can be bound to a differnt port, so  you can divert
> different packets to different sockets (with tun, how do you do that?)

Multiple tun devices ?

Darren