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To: Robert Watson <rwatson@FreeBSD.ORG>
From: Mark Murray <markm@FreeBSD.ORG>
Date: Thu, 05 Oct 2006 14:54:39 +0100
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Cc: Ricardo Nabinger Sanchez <rnsanchez@wait4.org>, freebsd-arch@FreeBSD.ORG
Subject: Re: PRNG on FreeBSD 
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Robert Watson writes:
> 
> On Wed, 4 Oct 2006, Ricardo Nabinger Sanchez wrote:
> 
> > Snooping around Wikipedia, I got curious about if it'd worth the
> > effort going from Yarrow [1] to Fortuna [2] algorithm, as the
> > authors (seems to) claim that the latter is better/more secure.
> >
> > As someone (me) who knows very little on how to effectively
> > compromise a PRNG, what are the tradeoffs?  Yarrow is simpler/faster
> > than Fortuna?
>
> Yarrow is an older PRNG algorithm, and Fortuna is (as I understand
> it) generally considered its successor.  Mark Murray (CC'd), who
> implemented our current /dev/random and Yarrow code, has been working
> on a Fortuna implementation for FreeBSD.

Indeed. Fortuna is also looking like it is going to be a significant
resource hog WRT memory, particularly on small/embedded devices.

I'm stalled right now (exam mode for two weeks) but its top of my TODO
list to get Fortuna off my chest once I'm done.

I think I'm going to need a hand with the kernel bits; I keep running
into problems I can't think of decent questions for.

M
--
Mark R V Murray - Cert APS(Open) Dip Phys(Open) BSc Open(Open)
What is the most interesting question you have asked?
What, if any, was the answer?