Date: Wed, 25 Oct 2000 14:50:29 +0400 From: =?koi8-r?B?4c7E0sXKIP7F0s7P1w==?= <ache@nagual.pp.ru> To: Terry Lambert <tlambert@primenet.com> Cc: Warner Losh <imp@village.org>, current@FreeBSD.ORG, markm@FreeBSD.ORG Subject: Re: entropy reseeding is totally broken Message-ID: <20001025145028.A81143@nagual.pp.ru> In-Reply-To: <200010251035.DAA19676@usr02.primenet.com>; from tlambert@primenet.com on Wed, Oct 25, 2000 at 10:35:55AM %2B0000 References: <200010241816.MAA17356@harmony.village.org> <200010251035.DAA19676@usr02.primenet.com>
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On Wed, Oct 25, 2000 at 10:35:55AM +0000, Terry Lambert wrote: > > I see the opposite. I see that without writing to the /dev/random > > device I get a cons is an object that cares fortune 99+% of the time > > on my first login. With it, I see more decently random fortunes (but > > I haven't done a statistical analysis of them to see how random things > > are). > > Is it just me, or have there been more problems achieving > real statistical randomness since /dev/random went in, than > at any other time in BSD history? > > I booted a 1.5 system a couple of times for grins. > > It gives you a different fortune each time. > > Note that 1.5 "lacked" /dev/random. It is because /dev/random totally ignore _time_ and not reseed from it, but no other randomness source available at boot time. At the boot /dev/random tries to reseed from other sources (excepting time), but: 1) Reseed code is broken, in come case (as I describe) all reseeding data is ignored, only its size is counted until it was as big as 16384. Mark not fix it yet at this moment nor confirm he is able to reproduce this bug. 2) Reseeding state may not preserve across the boot due to various reasons like panic, etc. Since _time_ is ignored, all other data /etc/rc tries to collect now can be non-random _easily_! Unless _time_ will be used, /dev/random is plain unusable for production usage. -- Andrey A. Chernov http://ache.pp.ru/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message
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