DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id
	:list-unsubscribe:list-subscribe:list-archive:list-post
	:list-help:sender:message-id:date:to:from:subject:in-reply-to
	:references:mime-version:content-type; q=dns; s=default; b=iMHay
	ttCFnrQK59e7PTjUhIDfjsL4EcpQmWulH+/vap/uZ4x0TOQaL0mrrg/2tLbRDrGW
	gyYjWkTtzlcK491xAowddxYM+576/P9wL8vYNh5PbWJtoedkYDS4qAca7wt39h4X
	ib3fQ+SjW9BH5YmJNXx4gODRk9EJOz8ZAHtiRE=
Mailing-List: contact cygwin-help@cygwin.com; run by ezmlm
Sender: cygwin-owner@cygwin.com
Mail-Followup-To: cygwin@cygwin.com
Message-Id: <6.2.5.6.2.20131015100723.066d3e48@binnacle.cx>
Date: Tue, 15 Oct 2013 10:19:21 -0400
To: cygwin@cygwin.com
From: starlight.2013z3@binnacle.cx
Subject: Re: /dev/random does not block, emits poor entropy
In-Reply-To: <20131015140052.GE19383@calimero.vinschen.de>
References: <6.2.5.6.2.20130919015353.03a25398@binnacle.cx> <20131015140052.GE19383@calimero.vinschen.de>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Received-SPF: pass (mx.binnacle.cx: 172.29.87.10 is whitelisted by SPF-milter whitelist entry)

Yes, this is great.  Thank you!

Subsequent to my post I learned more
on the topic.  Is complex and loaded
with controversy.  Many cryptographers
assert that Linux's blocking
implementation creates vulnerability
to various timing attacks and that
/dev/urandom is essentially the same
as /dev/random on a practical level
--is better for not blocking.

But the Linex devs are smart folks
and have yet to be convinced. . .

Hardware RNG marketing is deceiving
when it talks about "true" RNG since
even quantum-effect number generators
have non-random patterns that must
be algorithmically cleansed.
Rather than a "true" RNG or TRNG, one
wants as CSPRNG (cryptographically
secure pseudorandom number generator)
that combines a good source of hardware
entropy and appropriate purifying
algorithms.

People get quite hot about the topic,
and apparently the Dilbert cartoon
applies at all times, regardless:

http://dilbert.com/strips/comic/2001-10-25/

When the Federal government shutdown ends
the pages here will contain good information
(NSA influence over NIST not withstanding):

http://csrc.nist.gov/groups/ST/toolkit/rng/index.html


At 16:00 10/15/2013 +0200, Corinna Vinschen wrote:
>/dev/random.  The new results with /dev/random are
>now along the lines of:
>
>  rngtest: bits received from input: 3059180032
>  rngtest: FIPS 140-2 successes: 152857
>  rngtest: FIPS 140-2 failures: 102
>  [...]
>
>which is another ~30% better result.  That
>should be sufficient, IMHO.
>
>
>Corinna
>


--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple