From owner-freebsd-current Fri Jul 21 8:58:55 2000 Delivered-To: freebsd-current@freebsd.org Received: from spirit.jaded.net (shortbus.jaded.net [216.94.132.8]) by hub.freebsd.org (Postfix) with ESMTP id 8DC8B37BCAC; Fri, 21 Jul 2000 08:58:51 -0700 (PDT) (envelope-from dan@spirit.jaded.net) Received: (from dan@localhost) by spirit.jaded.net (8.9.3/8.9.3) id LAA00864; Fri, 21 Jul 2000 11:58:46 -0400 (EDT) (envelope-from dan) Date: Fri, 21 Jul 2000 11:58:46 -0400 From: Dan Moschuk To: Kris Kennaway Cc: Mark Murray , current@FreeBSD.org Subject: Re: randomdev entropy gathering is really weak Message-ID: <20000721115846.C489@spirit.jaded.net> References: <20000718103729.A1221@spirit.jaded.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2i In-Reply-To: ; from kris@FreeBSD.org on Fri, Jul 21, 2000 at 03:46:31AM -0700 Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG | > | Gotcha - fix coming; I need to stash some randomness at shutdown time, and | > | use that to reseed the RNG at reboot time. | > | > What about saving the state of the RNG and re-reading it on bootup? That | > will allow Yarrow to continue right where it left off. :-) | | That's a bad thing. You don't want someone to be able to examine the exact | PRNG state at next boot by looking at your hard disk after the machine has | shut down. I don't see how. If the attacker has physical access to the machine, there are plenty worse things to be done than just reading the state of a PRNG. If the random device is initialized in single user mode, and the file is then unlink()ed, I don't see any problems with that. -Dan To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message