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From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@des.no>
To: Pawel Jakub Dawidek <pjd@FreeBSD.org>
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Date: Tue, 25 Sep 2012 12:58:37 +0200
In-Reply-To: <20120925102240.GC1571@garage.freebsd.pl> (Pawel Jakub Dawidek's
	message of "Tue, 25 Sep 2012 12:22:41 +0200")
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Cc: Jonathan Anderson <jonathan.anderson@cl.cam.ac.uk>,
	John Baldwin <jhb@freebsd.org>, Ben Laurie <benl@freebsd.org>,
	freebsd-security@freebsd.org, RW <rwmaillists@googlemail.com>,
	Mariusz Gromada <mariusz.gromada@gmail.com>
Subject: Re: Collecting entropy from device_attach() times.
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Pawel Jakub Dawidek <pjd@FreeBSD.org> writes:
> Note that this fake data is the hardest to gather entropy from, as it
> doesn't interact with any external hardware. I'm all for testing it on
> real hardware and I expect to be able to gather even more entropy from
> it (so discarding less than top 7 bits). The problem with making
> observations during boot takes much, much longer, so it will limit the
> number os samples significantly, and as you know the more samples the
> better.

I have a handful of SFF machines which support PXE.  I can easily set up
an NFS root where /etc/rc just remounts / rw, dumps the data and
reboots.  With a sub-minute cycle time, I can get a couple of hundred
thousand samples per machine over the weekend.

(I don't even need PXE - they'll probably boot faster from USB sticks or
disks)

DES
--=20
Dag-Erling Sm=C3=B8rgrav - des@des.no