From mboxrd@z Thu Jan 1 00:00:00 1970 From: ludo@gnu.org (Ludovic =?utf-8?Q?Court=C3=A8s?=) Subject: Re: /dev/urandom Date: Wed, 11 Jul 2018 00:18:21 +0200 Message-ID: <87muuypweq.fsf@gnu.org> References: <20180710182211.75442f8b@scratchpost.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Return-path: Received: from eggs.gnu.org ([2001:4830:134:3::10]:38911) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fd0xj-0003Zy-C6 for guix-devel@gnu.org; Tue, 10 Jul 2018 18:18:24 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fd0xi-0000nb-LR for guix-devel@gnu.org; Tue, 10 Jul 2018 18:18:23 -0400 In-Reply-To: <20180710182211.75442f8b@scratchpost.org> (Danny Milosavljevic's message of "Tue, 10 Jul 2018 18:22:11 +0200") List-Id: "Development of GNU Guix and the GNU System distribution." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org Sender: "Guix-devel" To: Danny Milosavljevic Cc: guix-devel@gnu.org Hello Danny, Danny Milosavljevic skribis: > u-boot tools/sunxi-spl-image-builder.c reads from /dev/urandom . > > For reproducibility I'd like this to be a static file. Do we already hav= e one > for this purpose? I=E2=80=99d be wary of introducing a static /dev/urandom. It could do more= than we want, or we could leave it around in places where it shouldn=E2=80=99t b= e. For reproducibility purposes, (gnu system vm) precomputes file system UUIDs, for instance, instead of letting them be computed as a function of /dev/urandom. Dunno if a similar technique could be used here. Otherwise, what about patching U-Boot so that the file above honors and environment variable or something that would allow us to specify a seed? Ludo=E2=80=99.