From owner-freebsd-net  Thu Aug  9 20:52: 8 2001
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Date: Thu, 9 Aug 2001 20:51:56 -0700 (PDT)
From: Yu-Shun Wang <yushunwa@isi.edu>
To: Warner Losh <imp@harmony.village.org>
Cc: Jonathan Chen <jon@FreeBSD.ORG>, <net@FreeBSD.ORG>,
	<hackers@FreeBSD.ORG>
Subject: Re: forwarding broadcast 
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Hi,
	Sorry for not making it clear. I believe RFC 2644
	actually suggested that routers MUST default to
	disabling directed broadcast except explicitly
	configured to do so. But I guess one can never
	be too careful. :-)

	yushun.

____________________________________________________________________________
Yu-Shun Wang <yushunwa@isi.edu>               Information Sciences Institute
                                           University of Southern California

On Thu, 9 Aug 2001, Warner Losh wrote:

> In message <20010809102555.Y42772-100000@amc.isi.edu> Yu-Shun Wang writes:
> : 	I think it's specified in RFC 2644. It might be useful
> : 	to site it in the comments of the code.
>
> There were several incidents in the early days of the internet when
> this functionality was in place that caused all kinds of problems.
> Look at the trouble that Jordan got into in 1983 (search the RISKS
> archives) when he send a broadcast to all (which sent the wall to the
> entire internet at the time).  While this wasn't exactly a network
> level broadcast, consider carefully the ramifications.
>
> There are many cases where could be useful turns into a security
> nightmare, so I'd be extremely reluctant to include this patch...
>
> Warner
>


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