From owner-freebsd-arch@FreeBSD.ORG Fri Aug 9 07:46:25 2013 Return-Path: Delivered-To: freebsd-arch@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id DC6D0204 for ; Fri, 9 Aug 2013 07:46:24 +0000 (UTC) (envelope-from fabient@freebsd.org) Received: from work.netasq.com (gwlille.netasq.com [91.212.116.1]) by mx1.freebsd.org (Postfix) with ESMTP id 7612F2445 for ; Fri, 9 Aug 2013 07:46:23 +0000 (UTC) Received: from work.netasq.com (localhost [127.0.0.1]) by work.netasq.com (Postfix) with ESMTP id 234AF2706321; Fri, 9 Aug 2013 09:46:17 +0200 (CEST) Received: from [10.2.1.1] (unknown [91.212.116.2]) by work.netasq.com (Postfix) with ESMTPSA id EB5AA2706092; Fri, 9 Aug 2013 09:46:16 +0200 (CEST) Subject: Re: random(4) plugin infrastructure for mulitple RNG in a modular fashion Mime-Version: 1.0 (Apple Message framework v1283) From: Fabien Thomas In-Reply-To: <50BE6942-CC39-413C-8E14-C6B93440901B@grondar.org> Date: Fri, 9 Aug 2013 09:46:16 +0200 Message-Id: References: <20130807182858.GA79286@dragon.NUXI.org> <20130807192736.GA7099@troutmask.apl.washington.edu> <5203968D.7060508@freebsd.org> <7018AAA9-0A88-430F-96B7-867E5F529B36@bsdimp.com> <50BE6942-CC39-413C-8E14-C6B93440901B@grondar.org> To: Mark R V Murray X-Mailer: Apple Mail (2.1283) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.14 Cc: freebsd-arch@freebsd.org X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 09 Aug 2013 07:46:25 -0000 >>=20 >> On Aug 8, 2013, at 7:01 AM, Andrey Chernov wrote: >>=20 >>> Many years ago I already suggest to de-modularize random (making it = not >>> optional), with fallback to yarrow if hardware RNGs can't be probed = or >>> not configured. >>=20 >> I think that the 'fallback to yarrow' is necessary here. >=20 > My current inclination is to make Yarrow the basic device (or "Fortuna = Lite", but that is a problem for MUCH later), and make the hardware = devices feed Yarrow, if they are present. I also think this is the best option to have as a default: - Keep a good software random - Add more source of entropy at early boot - Dont trust HW random (keep it as one probed source of seed) User can choose to switch to pure HW random to replace SW. A good source of information here: = http://th.informatik.uni-mannheim.de/people/lucks/papers/Ferguson/Fortuna.= pdf Fabien=