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Date: Wed, 01 Aug 2007 15:34:32 +0100
From: "Bruce M. Simpson" <bms@incunabulum.net>
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To: "Christian S.J. Peron" <csjp@FreeBSD.org>
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Cc: freebsd-net@freebsd.org, rwatson@freebsd.org,
	Julian Elischer <julian@elischer.org>
Subject: Re: divert and deadlock issues
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Christian S.J. Peron wrote:
> Well, it's still the intent to keep the ability to divert and re-inject
> multicast packets.  This change would basically say: "You cant specify
> multicast options via the divert socket". Which in practice doesn't
> happen anyway (where I looked).
>
> I dont think we should be specifying multicast options on divert sockets.
> It's not the right place to be manipulating multicast parameters.  Multicast
> parameters should be set on the sockets that originally transmitted or
> received the packets.  I dont think divert falls into this category.
>   
Correct.

The definition of what a divert socket is and does, falls outside the 
definition of what a multicast socket endpoint is.
Divert sockets exist to munge packets as they flow up or down the stack.

If the additional complexity of treating divert sockets as multicast 
endpoints causes locking issues in the stack, common sense suggests we 
should deprecate that behaviour.

BMS