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Date: Thu, 19 Sep 2013 01:55:58 -0400
To: cygwin AT cygwin DOT com
From: starlight DOT 2013z3 AT binnacle DOT cx
Subject: /dev/random does not block, emits poor entropy
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For contrast, here is a 'rngtest' run against a
3.1.8 Linux kernel with /dev/random enhanced by
the output of a STMicroelectronics ST33 TPM PRNG
(via 'rngd' v4).

bits received from input: 62380032
FIPS 140-2 successes: 3115
FIPS 140-2 failures: 4
FIPS 140-2(2001-10-10) Monobit: 0
FIPS 140-2(2001-10-10) Poker: 0
FIPS 140-2(2001-10-10) Runs: 3
FIPS 140-2(2001-10-10) Long run: 1
FIPS 140-2(2001-10-10) Continuous run: 0
input channel speed: (min=21.119; avg=42.165; max=136.844)Kibits/s
FIPS tests speed: (min=41.374; avg=104.495; max=107.154)Mibits/s
Program run time: 1445.324494 seconds

That's three bit runs and one long bit run
in close to 8MB of random data.  Is well
inside the FIPS 140-2 document requirements.
Would likely be bad if there were none.
ST claims their PRNG is a

   AIS-31 Class P2 compliant true random
   number generator (TRNG)

The 'rngtest' output above is edited slightly
for better reading.


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