From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 33142C433F5 for ; Wed, 9 Feb 2022 11:57:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231768AbiBIL5o (ORCPT ); Wed, 9 Feb 2022 06:57:44 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57230 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231811AbiBIL4G (ORCPT ); Wed, 9 Feb 2022 06:56:06 -0500 Received: from isilmar-4.linta.de (isilmar-4.linta.de [136.243.71.142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 95C67E00FA48; Wed, 9 Feb 2022 02:56:33 -0800 (PST) X-isilmar-external: YES X-isilmar-external: YES X-isilmar-external: YES X-isilmar-external: YES X-isilmar-external: YES Received: from owl.dominikbrodowski.net (owl.brodo.linta [10.2.0.111]) by isilmar-4.linta.de (Postfix) with ESMTPSA id 74C4F201432; Wed, 9 Feb 2022 08:31:16 +0000 (UTC) Received: by owl.dominikbrodowski.net (Postfix, from userid 1000) id 5EBE180F74; Wed, 9 Feb 2022 09:30:22 +0100 (CET) Date: Wed, 9 Feb 2022 09:30:22 +0100 From: Dominik Brodowski To: "Jason A. Donenfeld" Cc: linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, tytso@mit.edu, ebiggers@kernel.org Subject: Re: [PATCH v2 8/9] random: use hash function for crng_slow_load() Message-ID: References: <20220209011919.493762-1-Jason@zx2c4.com> <20220209011919.493762-9-Jason@zx2c4.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220209011919.493762-9-Jason@zx2c4.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Wed, Feb 09, 2022 at 02:19:18AM +0100 schrieb Jason A. Donenfeld: > Since we have a hash function that's really fast, and the goal of > crng_slow_load() is reportedly to "touch all of the crng's state", we > can just hash the old state together with the new state and call it a > day. This way we dont need to reason about another LFSR or worry about > various attacks there. This code is only ever used at early boot and > then never again. Reviewed-by: Dominik Brodowski Thanks, Dominik