From owner-freebsd-hackers@FreeBSD.ORG  Thu Dec 24 14:47:08 2009
Return-Path: <owner-freebsd-hackers@FreeBSD.ORG>
Delivered-To: freebsd-hackers@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 79F57106566B
	for <freebsd-hackers@freebsd.org>; Thu, 24 Dec 2009 14:47:08 +0000 (UTC)
	(envelope-from rwmaillists@googlemail.com)
Received: from mail-fx0-f227.google.com (mail-fx0-f227.google.com
	[209.85.220.227])
	by mx1.freebsd.org (Postfix) with ESMTP id 0B86B8FC17
	for <freebsd-hackers@freebsd.org>; Thu, 24 Dec 2009 14:47:07 +0000 (UTC)
Received: by fxm27 with SMTP id 27so8368839fxm.3
	for <freebsd-hackers@freebsd.org>; Thu, 24 Dec 2009 06:47:07 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
	d=googlemail.com; s=gamma;
	h=domainkey-signature:received:received:date:from:to:subject
	:message-id:in-reply-to:references:x-mailer:mime-version
	:content-type:content-transfer-encoding;
	bh=RTf7Rz7bEW3dPURrEN2dWwhhCvXJtifSn5pin+gx0+Y=;
	b=r4YPAkfHqNwcDl17g4hofww6DCPzbVQ2DNT8pkeNMrDxEZNwRJWtKeOTAale9lDXqe
	WjiC9/GhroCk+OAgKNsoatN+7j2DcoKTLK1VltKucFb0ROnv4sd2lSU/70pi9yTyHYEd
	HXBsx4Y8s/duIxhqofRO9VBzSTC41QamdSM14=
DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma;
	h=date:from:to:subject:message-id:in-reply-to:references:x-mailer
	:mime-version:content-type:content-transfer-encoding;
	b=nIXIP9K3RkdnARip7VdBI0uynHR+oU6ygZF8Mum8c4DLBECoOoTv9QSpsJzcFifm31
	7H2J3KAIMQcrvOq8sJV8OEr5fY0D5yXG+TG/zJy/k/VtpYDO3L6AVzJu9vpn01Oq1lpe
	hGdwkWoiQGvQv5Im+Vw+R8dCp6k4xbCjW2TYw=
Received: by 10.223.143.73 with SMTP id t9mr4929870fau.89.1261666026565;
	Thu, 24 Dec 2009 06:47:06 -0800 (PST)
Received: from gumby.homeunix.com (bb-87-81-140-128.ukonline.co.uk
	[87.81.140.128])
	by mx.google.com with ESMTPS id z10sm12840052fka.30.2009.12.24.06.47.05
	(version=SSLv3 cipher=RC4-MD5); Thu, 24 Dec 2009 06:47:05 -0800 (PST)
Date: Thu, 24 Dec 2009 14:47:03 +0000
From: RW <rwmaillists@googlemail.com>
To: freebsd-hackers@freebsd.org
Message-ID: <20091224144703.482896eb@gumby.homeunix.com>
In-Reply-To: <5a5b03660912240445x7df1498dt42e29d93105efebc@mail.gmail.com>
References: <5a5b03660912240445x7df1498dt42e29d93105efebc@mail.gmail.com>
X-Mailer: Claws Mail 3.7.3 (GTK+ 2.18.5; i386-portbld-freebsd8.0)
Mime-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Subject: Re: yarrow random generator
X-BeenThere: freebsd-hackers@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Technical Discussions relating to FreeBSD
	<freebsd-hackers.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>, 
	<mailto:freebsd-hackers-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-hackers>
List-Post: <mailto:freebsd-hackers@freebsd.org>
List-Help: <mailto:freebsd-hackers-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>,
	<mailto:freebsd-hackers-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 24 Dec 2009 14:47:08 -0000

On Thu, 24 Dec 2009 15:45:15 +0300
Paul Graphov <graphov@gmail.com> wrote:

> Hello guys,
> 
> I've looked at FreeBSD 8.0 cryptographically secure pseudorandom
> numbers generator and have a question. It looks like a bug but I'am
> not sure.
> 
> In file sys/dev/randomdev.c, function random_read:
> 
>         if (!random_systat.seeded)
>                 error = (*random_systat.block)(flag);
> 
> It blocks until PRNG is seeded.

random_systat.seeded is initialized to 1 and it's never set to anything
other than 1

I got impression that blocking was something that seemed like a good
idea at the time, but fell-off half-way through coding. It's not a
good idea to block /dev/random, without a separate urandom.