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From: Mark Murray <markm@FreeBSD.org>
Date: Sat, 15 Sep 2012 09:13:49 +0100
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Cc: Arthur Mesh <arthurmesh@gmail.com>,
	Ian Lepore <freebsd@damnhippie.dyndns.org>,
	Doug Barton <dougb@freebsd.org>, Ben Laurie <benl@freebsd.org>,
	freebsd-security@freebsd.org, "Bjoern A. Zeeb" <bz@freebsd.org>
Subject: Re: svn commit: r239569 - head/etc/rc.d
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RW writes:
> So far no one has come up with a single cogent argument for
> compression. If you replace compression with hashing then the need
> modifying the kernel code is eliminated.

Compression reduces file size without losing entropy; in fact it serves
as an entropy concentrator. That said, I agree that its output is still
not small enough and its speed is unacceptable.

As for modifying kernel code,

$ cat /dev/zero > /dev/random

... can swamp entropy harvesting. Its an obvious attack and easily
spotted/thwarted, but I'd like to defend against it; the current code is
a bit too naive.

M
--
Mark R V Murray
Cert APS(Open) Dip Phys(Open) BSc Open(Open) BSc(Hons)(Open)
Pi: 132511160