Messages in this thread | | | Date | Thu, 12 Sep 2013 17:31:48 -0400 | From | Jörn Engel <> | Subject | Re: [PATCH] /dev/random: Insufficient of entropy on many architectures |
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On Tue, 10 September 2013 15:08:12 -0700, John Stultz wrote: > Though > I probably should be hesitant with my suggestions, as I'm not well > versed in RNG theory.
The basic principle of Ted's RNG is very simple and quite sane: - You collect as much data as possible, some of which is (hopefully) unpredictable. - All the data gets dumped into a small buffer. - When reading from the buffer, you create a crypto-hash of the entire buffer. Even if most of the buffer is predictable, the few unpredictable bits will randomly flip every output bit. - Half of the hash gets returned to the reader, the other half gets added back into the pool.
It doesn't matter if you collect predictable data - it neither helps nor hurts. But you should collect as much unpredictable data as possible and do it as cheaply as possible. If you want to improve the RNG, you either collect more data, collect better (less predictable) data or make the collection cheaper.
Jörn
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