From owner-freebsd-net@FreeBSD.ORG  Mon Jan 19 03:58:02 2004
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To: Maxim Konovalov <maxim@macomnet.ru>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Mon, 19 Jan 2004 14:39:20 +0300."
             <20040119143315.N81347@news1.macomnet.ru> 
Date: Mon, 19 Jan 2004 12:58:00 +0100
Message-ID: <92245.1074513480@critter.freebsd.dk>
cc: net@freebsd.org
Subject: Re: Multihomed UDP server 
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In message <20040119143315.N81347@news1.macomnet.ru>, Maxim Konovalov writes:
>On Mon, 19 Jan 2004, 12:07+0100, Poul-Henning Kamp wrote:
>
>> Simple question:
>>
>> Very simple UDP server daemon.
>>
>> Many clients (connect(2)'ing a socket for each is not an option)
>>
>> Multihomed machine.
>>
>> What's the simple trick to replying with the same source-IP as the
>> client used as destination-IP ?
>
>Probably bin/58012 worth to look (Multihomed tftpd enhancement).  Yes,
>it relies on protocol but still.

But that's not a general solution, and it certainly doesn't solve
the problem for my application.

I'm considering ways to make sendmsg(2)/recvmsg(2) DTRT, and my
current candidate is give them a flag bit which says "msg_name has
both addresses".

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.