Roland Smith wrote:
On Thu, Sep 13, 2007 at 05:31:55PM +0100, RW wrote:
On Thu, 13 Sep 2007 17:36:30 +0200
Roland Smith <[EMAIL PROTECTED]> wrote:

On Thu, Sep 13, 2007 at 04:56:26PM +0200, Per olof Ljungmark wrote:
Hi,

Could someone on the list point me to a document that explains the functionality of /dev/random in FreeBSD in a little more depth than
the man page? In other OS's I've looked at random and urandom are
different, here it's a symlink (talking about RELENG-6 onwards).
FreeBSD uses the yarrow algorithm, as mentioned in random(4). See http://en.wikipedia.org/wiki/Yarrow_algorithm
http://www.schneier.com/yarrow.html
Yarrow is reseeded with interrupt entropy, and is supposedly good
enough not to require the amount of entropy to be tracked.
So /dev/random need not block, and there's no need for a separate
non-blocking device.

On the website it says that the original yarrow algorithm is no longer
supported. It seems to have been replaced by the fortuna algorithm.

I can't see from the source if /usr/src/sys/dev/random/yarrow.* use the
original yarrow algorithm, or the improved yarrow-160 aka fortuna. The use of
crypto/rijndael/rijndael-api-fst.h and crypto/sha2/sha2.h seem to
indicate the latter though.

Should I conclude then that randomness is sufficient and performance is a non-issue?

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