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=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS 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 725B5C46475 for ; Mon, 5 Nov 2018 10:20:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 38DA220825 for ; Mon, 5 Nov 2018 10:20:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=linaro.org header.i=@linaro.org header.b="KJptL+Xj" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 38DA220825 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728928AbeKETj3 (ORCPT ); Mon, 5 Nov 2018 14:39:29 -0500 Received: from mail-it1-f195.google.com ([209.85.166.195]:53832 "EHLO mail-it1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726086AbeKETj2 (ORCPT ); Mon, 5 Nov 2018 14:39:28 -0500 Received: by mail-it1-f195.google.com with SMTP id r12-v6so9107232ita.3 for ; Mon, 05 Nov 2018 02:20:29 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=VhdvL1uLGtlLDhJabG/pQgJeee3A3ZGaGzNYTsDl2cM=; b=KJptL+XjWSYq2VyQ5VSBPJbYELstFfzzcNH1PN0wN0+4Htju18DiCreXlTg+RfXJ/0 k0EvS31NWZO9qX+w2y/VGE/Ib1LvIQ6X4TuvkgotpG6H7TjcmmDnNbQiFRQUVgDt0VLj BCl3ehT87z4DF3paIKe7DQnDkveaWU7OJZb10= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=VhdvL1uLGtlLDhJabG/pQgJeee3A3ZGaGzNYTsDl2cM=; b=VNkxywa9y5zc6WFQqGgcsAk57y+rHVAhBnkX3zlm6eRMgVwsiH6CPVKRn9HocAoCVy iqhNRQYjm/PjXEvURZKC+ean+ECD4KiqjyX2CZQbWeq6EzXziZi1BgRgXkys1Xs29qFQ J5h421AVHSlg+fBs84N9kOYpjg9hnUHhQ5MNA3lMAwzLdsPO8V8H2RT8NZozVY1CFpQl qs522F2VWXg6D4Zq8wS2qcVb+JfpJb/Kx26z/XwnvMUc911Q/nYuxmOI1MTMB3i7iIPX 4EsDRy/Jz5HtiO1++Rc3GHcTqsh8cqT3SHg3DITDpLndRfw9ezbWJKF0RxUKrNso0Nye y9Fw== X-Gm-Message-State: AGRZ1gKtLNQENCLfupAdY70eeXVisgMChqP18VKIwCmZcEOFhllafBT3 /gwJXpOEcUN13yQxqH4thJH99+075zeNf7NF1JuGaA== X-Google-Smtp-Source: AJdET5dmfRinnApLdMyfoDOXhe3vPmm2qAbVebEfDu/sdrxQyplaybCZ1YwVAW8Z+PLkMJJbcOFBb5LJHcYr2adGmdE= X-Received: by 2002:a02:9f85:: with SMTP id a5-v6mr19822545jam.2.1541413228819; Mon, 05 Nov 2018 02:20:28 -0800 (PST) MIME-Version: 1.0 Received: by 2002:a6b:4f16:0:0:0:0:0 with HTTP; Mon, 5 Nov 2018 02:20:28 -0800 (PST) In-Reply-To: References: <1541325924-14777-1-git-send-email-gilad@benyossef.com> <2578248.XAorIH2ink@tauon.chronox.de> From: Ard Biesheuvel Date: Mon, 5 Nov 2018 11:20:28 +0100 Message-ID: Subject: Re: [PATCH] crypto: mark cts(cbc(aes)) as FIPS allowed To: Gilad Ben-Yossef Cc: =?UTF-8?Q?Stephan_M=C3=BCller?= , Herbert Xu , David Miller , Ofir Drang , Yael Chemla , Linux Crypto Mailing List , Linux kernel mailing list Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 5 November 2018 at 10:18, Gilad Ben-Yossef wrote: > Hi Stephan, > > On Mon, Nov 5, 2018 at 10:50 AM Stephan Mueller wrote: >> >> Am Sonntag, 4. November 2018, 11:05:24 CET schrieb Gilad Ben-Yossef: >> >> Hi Gilad, >> >> > As per Sp800-38A addendum from Oct 2010[1], cts(cbc(aes)) is >> > allowed as a FIPS mode algorithm. Mark it as such. >> > >> > [1] https://csrc.nist.gov/publications/detail/sp/800-38a/addendum/final >> >> There are several types of CTS approaches. Only three of those are listed in >> the SP800-38A addendum. The source code only refers to some RFCs. >> >> Did you check whether the CTS implementation matches one or more of the types >> listed in the addendum? If yes, may I suggest to add a small statement in the >> code noting this fact? > > Yes, AFAIK the software implements CBC-CS3 as described in the document. > You have a very good point about this not document anywhere. I will > send a patch. > I agree that it makes sense to document this. > While we're at it, does someone find it useful if I implemented the > other two modes? > They are part of the standard as well, although I am not sure that in > itself is sufficient cause. > Nope. The linux crypto API is not a general purpose cryptography toolkit, it should only offer what we actually use in the kernel, or we'll either end up with bitrot or with a disproportionate maintenance burden for stuff nobody actually uses.