From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932779AbcFTQnh (ORCPT ); Mon, 20 Jun 2016 12:43:37 -0400 Received: from mail.eperm.de ([89.247.134.16]:37408 "EHLO mail.eperm.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752500AbcFTQn2 (ORCPT ); Mon, 20 Jun 2016 12:43:28 -0400 From: Stephan Mueller To: "Theodore Ts'o" Cc: Herbert Xu , Linux Kernel Developers List , linux-crypto@vger.kernel.org, andi@firstfloor.org, sandyinchina@gmail.com, jsd@av8n.com, hpa@zytor.com Subject: Re: [PATCH 5/7] random: replace non-blocking pool with a Chacha20-based CRNG Date: Mon, 20 Jun 2016 17:49:17 +0200 Message-ID: <2101992.L9gKN5cFdv@tauon.atsec.com> User-Agent: KMail/4.14.10 (Linux/4.4.9-300.fc23.x86_64; KDE/4.14.20; x86_64; ; ) In-Reply-To: <20160620150147.GD9848@thunk.org> References: <1465832919-11316-1-git-send-email-tytso@mit.edu> <20160620051917.GA8719@gondor.apana.org.au> <20160620150147.GD9848@thunk.org> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Montag, 20. Juni 2016, 11:01:47 schrieb Theodore Ts'o: Hi Theodore, > > So simply doing chacha20 encryption in a tight loop in the kernel > might not be a good proxy for what would actually happen in real life > when someone calls getrandom(2). (Another good question to ask is > when someone might be needing to generate millions of 256-bit session > keys per second, when the D-H setup, even if you were using ECCDH, > would be largely dominating the time for the connection setup anyway.) Is speed everything we should care about? What about: - offloading of crypto operation from the CPU - potentially additional security features a hardware cipher may provide like cache coloring attack resistance? Ciao Stephan