From: Phillip Susi <psusi@cfl.rr.com>
To: Theodore Tso <tytso@mit.edu>, Matt Mackall <mpm@selenic.com>,
Marc Haber <mh+linux-kernel@zugschlus.de>,
Eric Dumazet <dada1@cosmosbay.com>,
Alan Cox <alan@lxorguk.ukuu.org.uk>,
Adrian Bunk <bunk@kernel.org>,
linux-kernel@vger.kernel.org, David.S.Mille@vax.1wt.eu
Subject: Re: Why does reading from /dev/urandom deplete entropy so much?
Date: Tue, 11 Dec 2007 14:46:40 -0500 [thread overview]
Message-ID: <475EE920.7000108@cfl.rr.com> (raw)
In-Reply-To: <20071211013414.GS17037@thunk.org>
Theodore Tso wrote:
> Note that even paranoid applicatons should not be using /dev/random
> for session keys; again, /dev/random isn't magic, and entropy isn't
> unlimited. Instead, such an application should pull 16 bytes or so,
> and then use it to seed a cryptographic random number generator.
What good does using multiple levels of RNG do? Why seed one RNG from
another? Wouldn't it be better to have just one RNG that everybody
uses? Doesn't the act of reading from the RNG add entropy to it, since
no one reader has any idea how often and at what times other readers are
stirring the pool?
next prev parent reply other threads:[~2007-12-11 19:46 UTC|newest]
Thread overview: 77+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-12-04 11:41 Why does reading from /dev/urandom deplete entropy so much? Marc Haber
2007-12-04 14:16 ` Eric Dumazet
2007-12-04 16:18 ` Adrian Bunk
2007-12-04 16:47 ` Alan Cox
2007-12-04 18:17 ` Eric Dumazet
2007-12-05 21:26 ` Matt Mackall
2007-12-06 7:02 ` Eric Dumazet
2007-12-06 16:09 ` Matt Mackall
2007-12-09 12:42 ` Marc Haber
2007-12-09 16:16 ` Matt Mackall
2007-12-10 23:06 ` Marc Haber
2007-12-10 23:35 ` Matt Mackall
2007-12-11 1:34 ` Theodore Tso
2007-12-11 19:46 ` Phillip Susi [this message]
2007-12-11 20:02 ` Ray Lee
2007-12-12 5:34 ` David Schwartz
2007-12-04 16:54 ` Ray Lee
2007-12-04 16:55 ` Alan Cox
2007-12-04 18:02 ` Matt Mackall
2007-12-04 19:50 ` Theodore Tso
2007-12-04 20:36 ` Matt Mackall
2007-12-04 20:40 ` Alan Cox
2007-12-04 20:48 ` Mike McGrath
2007-12-04 21:54 ` Matt Mackall
2007-12-04 22:03 ` Theodore Tso
2007-12-04 22:12 ` Mike McGrath
2007-12-04 22:28 ` Matt Mackall
2007-12-04 21:08 ` Matt Mackall
2007-12-04 21:18 ` Mike McGrath
2007-12-04 22:15 ` Matt Mackall
2007-12-04 22:23 ` Mike McGrath
2007-12-04 22:33 ` Matt Mackall
2007-12-05 14:26 ` Mike McGrath
2007-12-05 14:49 ` Theodore Tso
2007-12-08 7:38 ` Jon Masters
2007-12-08 17:32 ` Theodore Tso
2007-12-08 17:33 ` Mike McGrath
2007-12-08 17:49 ` Theodore Tso
2007-12-08 17:54 ` Jon Masters
2007-12-08 18:15 ` Matt Mackall
2007-12-08 18:24 ` Theodore Tso
2007-12-08 19:36 ` entropy gathering (was Re: Why does reading from /dev/urandom deplete entropy so much?) Jeff Garzik
2007-12-08 19:53 ` Matt Mackall
2007-12-08 20:04 ` Jeff Garzik
2007-12-08 20:19 ` Matt Mackall
2007-12-08 21:07 ` Willy Tarreau
2007-12-08 20:31 ` Theodore Tso
2007-12-08 20:47 ` Jeff Garzik
2007-12-08 20:42 ` Willy Tarreau
2007-12-08 23:47 ` Theodore Tso
2007-12-09 1:07 ` Jon Masters
2007-12-08 18:31 ` Why does reading from /dev/urandom deplete entropy so much? Jeff Garzik
2007-12-08 20:26 ` David Schwartz
2007-12-08 17:43 ` Matt Mackall
2007-12-08 17:47 ` Jon Masters
2007-12-08 18:05 ` Theodore Tso
2007-12-08 17:45 ` Jon Masters
2007-12-10 16:37 ` Pavel Machek
2007-12-04 18:01 ` Matt Mackall
2007-12-06 20:08 ` Bill Davidsen
2007-12-05 12:23 ` Marc Haber
2007-12-05 12:29 ` Marc Haber
2007-12-05 13:33 ` Theodore Tso
2007-12-05 15:10 ` Marc Haber
2007-12-06 19:32 ` Bill Davidsen
2007-12-08 22:03 ` Adrian Bunk
2007-12-08 22:10 ` Ismail Dönmez
2007-12-08 23:46 ` Theodore Tso
2007-12-09 5:21 ` Willy Tarreau
2007-12-09 6:52 ` Jon Masters
2007-12-09 6:21 ` Ismail Dönmez
2007-12-09 12:31 ` Theodore Tso
2007-12-09 14:06 ` Ismail Dönmez
2007-12-11 15:42 ` Bill Davidsen
2007-12-20 22:27 ` Marc Haber
2007-12-26 18:27 ` Phillip Susi
2007-12-04 18:49 ` Russ Dill
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