Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 26 Oct 2000 02:21:22 -0700
From:      Kris Kennaway <kris@citusc.usc.edu>
To:        Andrej Cernov <ache@nagual.pp.ru>
Cc:        Terry Lambert <tlambert@primenet.com>, Warner Losh <imp@village.org>, current@FreeBSD.ORG, markm@FreeBSD.ORG
Subject:   Re: entropy reseeding is totally broken
Message-ID:  <20001026022122.C69282@citusc17.usc.edu>
In-Reply-To: <20001025145028.A81143@nagual.pp.ru>; from ache@nagual.pp.ru on Wed, Oct 25, 2000 at 02:50:29PM %2B0400
References:  <200010241816.MAA17356@harmony.village.org> <200010251035.DAA19676@usr02.primenet.com> <20001025145028.A81143@nagual.pp.ru>

next in thread | previous in thread | raw e-mail | index | archive | help
On Wed, Oct 25, 2000 at 02:50:29PM +0400, Andrej Cernov wrote:

> It is because /dev/random totally ignore _time_ and not reseed from it,
> but no other randomness source available at boot time. 

We should probably be using the time since boot as ONE thing we seed
with, but it only provides maybe 3-4 bits of randomness - meaning if
thats all you seed with then your attacker has to brute-force 3-4 bits
of state to break the PRNG state as it was at boot time, hardly a
difficult challenge :-)

Kris


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-current" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20001026022122.C69282>