From: Bakul Shah <bakul@bitblocks.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
Subject: [9fans] bcm2835 random number generator
Date: Fri, 28 Mar 2014 10:19:30 -0700 [thread overview]
Message-ID: <20140328171930.EB2BCB827@mail.bitblocks.com> (raw)
I have put an initial version of raspberryPi hardware RNG
driver on sources. Supposedly bcm2835 uses a reverse bias
transistor as a noise source (though I couldn't find anything
a definitive source for this). FWIW, I ran the output through
rngtest (does FIPS 140-2 tests) and the failure rate is about
the same as FreeBSD's (about 1 out of 1000). rngtest tests at
a minimum 2*10^6 bits and plan9's stock /dev/random seems far
too slow so I didn't bother testing it.
Just copy /n/sources/contrib/bakul/random.c to sys/src/9/bcm
and rebuild 9pi.
Arguably this should be a new device, /dev/hrng or something,
but plan9's /dev/random code is very simple compared to the
elaborate versions on *BSD's. I have kept this one simple too.
If you are concerned about the quality of RNG or paranoid
about bcm2835's unpublic algorithm, feel free to complexify!
next reply other threads:[~2014-03-28 17:19 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-28 17:19 Bakul Shah [this message]
2014-03-28 21:09 ` erik quanstrom
2014-03-28 21:39 ` Bakul Shah
2014-03-28 23:51 ` erik quanstrom
2014-03-29 0:11 ` Bakul Shah
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