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 X-Spam-Level: X-Spam-Status: No, score=-3.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_NEOMUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 26D72C43444 for ; Sat, 12 Jan 2019 09:56:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EADCE2086C for ; Sat, 12 Jan 2019 09:56:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726647AbfALJ4e (ORCPT ); Sat, 12 Jan 2019 04:56:34 -0500 Received: from orcrist.hmeau.com ([104.223.48.154]:36280 "EHLO deadmen.hmeau.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725816AbfALJ4d (ORCPT ); Sat, 12 Jan 2019 04:56:33 -0500 Received: from gondobar.mordor.me.apana.org.au ([192.168.128.4] helo=gondobar) by deadmen.hmeau.com with esmtps (Exim 4.89 #2 (Debian)) id 1giG16-0004BP-FG; Sat, 12 Jan 2019 17:55:48 +0800 Received: from herbert by gondobar with local (Exim 4.89) (envelope-from ) id 1giG0t-0001Ye-PR; Sat, 12 Jan 2019 17:55:35 +0800 Date: Sat, 12 Jan 2019 17:55:35 +0800 From: Herbert Xu To: Eric Biggers Cc: Stephan =?iso-8859-1?Q?M=FCller?= , James Bottomley , Andy Lutomirski , "Lee, Chun-Yi" , "Rafael J . Wysocki" , Pavel Machek , linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, keyrings@vger.kernel.org, "Rafael J. Wysocki" , Chen Yu , Oliver Neukum , Ryan Chen , David Howells , Giovanni Gherdovich , Randy Dunlap , Jann Horn , Andy Lutomirski , linux-crypto@vger.kernel.org Subject: Re: [PATCH 4/6] crypto: hkdf - RFC5869 Key Derivation Function Message-ID: <20190112095535.36rh3ptnrf7yxacv@gondor.apana.org.au> References: <20190103143227.9138-1-jlee@suse.com> <20190109082103.GA8586@sol.localdomain> <9733066.Vrs4h5eWcW@positron.chronox.de> <2423373.Zd5ThvQH5g@positron.chronox.de> <20190112051252.GA639@sol.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20190112051252.GA639@sol.localdomain> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jan 11, 2019 at 09:12:54PM -0800, Eric Biggers wrote: > Hi Stephan, > > On Fri, Jan 11, 2019 at 08:10:39PM +0100, Stephan Müller wrote: > > The RFC5869 compliant Key Derivation Function is implemented as a > > random number generator considering that it behaves like a deterministic > > RNG. > > > > Thanks for the proof of concept! I guess it ended up okay. But can you explain > more the benefits of using the crypto_rng interface, as opposed to just some > crypto_hkdf_*() helper functions that are exported for modules to use? I agree. I see no benefit in adding this through the RNG API as opposed to just providing it as a helper. If some form of hardware acceleration were to eventuate in the future we could always revisit this. Cheers, -- Email: Herbert Xu Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt