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=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 95F8CC433E1 for ; Tue, 18 Aug 2020 13:51:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7D346206DA for ; Tue, 18 Aug 2020 13:51:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726747AbgHRNvg (ORCPT ); Tue, 18 Aug 2020 09:51:36 -0400 Received: from helcar.hmeau.com ([216.24.177.18]:42790 "EHLO fornost.hmeau.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726482AbgHRNvd (ORCPT ); Tue, 18 Aug 2020 09:51:33 -0400 Received: from gwarestrin.arnor.me.apana.org.au ([192.168.0.7]) by fornost.hmeau.com with smtp (Exim 4.92 #5 (Debian)) id 1k821Q-0006gY-He; Tue, 18 Aug 2020 23:51:29 +1000 Received: by gwarestrin.arnor.me.apana.org.au (sSMTP sendmail emulation); Tue, 18 Aug 2020 23:51:28 +1000 Date: Tue, 18 Aug 2020 23:51:28 +1000 From: Herbert Xu To: Ard Biesheuvel Cc: Linux Crypto Mailing List , Eric Biggers , Ben Greear Subject: Re: [PATCH 0/5] crypto: Implement cmac based on cbc skcipher Message-ID: <20200818135128.GA25652@gondor.apana.org.au> References: <20200802090616.1328-1-ardb@kernel.org> <20200818082410.GA24497@gondor.apana.org.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-crypto-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org On Tue, Aug 18, 2020 at 10:31:39AM +0200, Ard Biesheuvel wrote: > > What do you mean? You cannot implement cbcmac using a cbc skcipher > unless you provide a scratch buffer of arbitrary size as the > destination, in order to capture the skcipher output IV as the MAC. Please have a look at patch 6. The trick is to use an SG list chained to itself. Cheers, -- Email: Herbert Xu Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt