From: erik quanstrom <quanstro@quanstro.net>
To: 9fans@9fans.net
Subject: Re: [9fans] bcm2835 random number generator
Date: Fri, 28 Mar 2014 17:09:43 -0400 [thread overview]
Message-ID: <51844d0013c4336e5793156d18a91b3e@ladd.quanstro.net> (raw)
In-Reply-To: <20140328171930.EB2BCB827@mail.bitblocks.com>
On Fri Mar 28 13:21:35 EDT 2014, bakul@bitblocks.com wrote:
> 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!
i have not had luck with this. i get data aborts when booting
from flash, and hangs when rebooting via /dev/reboot.
- erik
next prev parent reply other threads:[~2014-03-28 21:09 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-28 17:19 Bakul Shah
2014-03-28 21:09 ` erik quanstrom [this message]
2014-03-28 21:39 ` Bakul Shah
2014-03-28 23:51 ` erik quanstrom
2014-03-29 0:11 ` Bakul Shah
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=51844d0013c4336e5793156d18a91b3e@ladd.quanstro.net \
--to=quanstro@quanstro.net \
--cc=9fans@9fans.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).