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Date: Sat, 8 Dec 2007 12:32:04 -0500
From: Theodore Tso <tytso@mit.edu>
To: Jon Masters <jonathan@jonmasters.org>
Cc: Mike McGrath <mmcgrath@redhat.com>, Matt Mackall <mpm@selenic.com>,
       Alan Cox <alan@lxorguk.ukuu.org.uk>, Ray Lee <ray@madrabbit.org>,
       Adrian Bunk <bunk@kernel.org>,
       Marc Haber <mh+linux-kernel@zugschlus.de>, linux-kernel@vger.kernel.org
Subject: Re: Why does reading from /dev/urandom deplete entropy so much?
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On Sat, Dec 08, 2007 at 02:37:57AM -0500, Jon Masters wrote:
> > BTW, You may be better off using "uuidgen -t" to generate the UUID in
> > the smolt RPM, since that will use 12 bits of randomness from
> > /dev/random, plus the MAC, address and timestamp.  So even if there is
> > zero randomness in /dev/random, and the time is January 1, 1970, at
> > least the MAC will contribute some uniqueness to the UUID.
> 
> I haven't checked how uuidgen uses the MAC, but I would suggest that
> that is not something Fedora should jump at doing - although it would
> help ensure unique UUIDs, it also contributes to the tinfoil hat
> responses that usually come up with things like smolt.

Huh?  What's the concern?  All you are submitting is a list of
hardware devices in your system.  That's hardly anything sensitive....

	 	    	 	  	 - Ted
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