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=-6.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 A27E8C433E6 for ; Wed, 10 Mar 2021 21:40:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 65D9364E33 for ; Wed, 10 Mar 2021 21:40:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230215AbhCJVkE (ORCPT ); Wed, 10 Mar 2021 16:40:04 -0500 Received: from mail.kernel.org ([198.145.29.99]:42384 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229563AbhCJVjg (ORCPT ); Wed, 10 Mar 2021 16:39:36 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3D14864FC4; Wed, 10 Mar 2021 21:39:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1615412375; bh=UdFxVt64TzjKasA+NMSYVTgOVpISnwKFURrW8ppuVck=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=El7iw81ezSJi4ARA7ejwk5ECH5c2j22Aay12Zi77N7B5T7/Fdw7c3wOJk35JlyBBW H8WtGS3rFYrYVYZcXQBFzQXDoeYjMeQ0/ElxndxpDnp1HpkvBz4CVjJ5952mcg7tgn LFZ9hXoZuTr4QdTJU7dhoKWkgOR2hOpRdFhAu/XGuywTu87XwgQhE7/37TEDLe92/Y +W762Xh/CO/ZL4zcdqk7e6VMUgL2uy4RpzpNeeVfTVLHhuh5UcUUNTSH1RGuoyMweZ sDCpsIkSFxOruGMEWq92/6GdUo/G748CQ/UqHa06QogWLJ/SqVhsm3M93XDkKmBOMJ vODf01DZHbIog== Date: Wed, 10 Mar 2021 23:39:11 +0200 From: Jarkko Sakkinen To: Jia Zhang Cc: Andy Lutomirski , Tianjia Zhang , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , Sean Christopherson , Shuah Khan , X86 ML , linux-sgx@vger.kernel.org, "open list:KERNEL SELFTEST FRAMEWORK" , LKML Subject: Re: [PATCH] selftests/sgx: fix EINIT failure dueto SGX_INVALID_SIGNATURE Message-ID: References: <20210301051836.30738-1-tianjia.zhang@linux.alibaba.com> <3bcdcf04-4bed-ed95-84b6-790675f18240@linux.alibaba.com> <1f5c2375-39e2-65a8-3ad3-8dc43422f568@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1f5c2375-39e2-65a8-3ad3-8dc43422f568@linux.alibaba.com> Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org On Wed, Mar 10, 2021 at 08:44:44PM +0800, Jia Zhang wrote: > > > On 2021/3/2 下午9:47, Jarkko Sakkinen wrote: > > On Mon, Mar 01, 2021 at 09:54:37PM -0800, Andy Lutomirski wrote: > >> On Mon, Mar 1, 2021 at 9:06 PM Tianjia Zhang > >> wrote: > >>> > >>> > >>> > >>> On 3/1/21 5:54 PM, Jarkko Sakkinen wrote: > >>>> On Mon, Mar 01, 2021 at 01:18:36PM +0800, Tianjia Zhang wrote: > >>>>> q2 is not always 384-byte length. Sometimes it only has 383-byte. > >>>> > >>>> What does determine this? > >>>> > >>>>> In this case, the valid portion of q2 is reordered reversely for > >>>>> little endian order, and the remaining portion is filled with zero. > >>>> > >>>> I'm presuming that you want to say "In this case, q2 needs to be reversed because...". > >>>> > >>>> I'm lacking these details: > >>>> > >>>> 1. Why the length of Q2 can vary? > >>>> 2. Why reversing the bytes is the correct measure to counter-measure > >>>> this variation? > >>>> > >>>> /Jarkko > >>>> > >>> > >>> When use openssl to generate a key instead of using the built-in > >>> sign_key.pem, there is a probability that will encounter this problem. > >>> > >>> Here is a problematic key I encountered. The calculated q1 and q2 of > >>> this key are both 383 bytes, If the length is not processed, the > >>> hardware signature will fail. > >> > >> Presumably the issue is that some keys have parameters that have > >> enough leading 0 bits to be effectively shorter. The openssl API > >> (and, sadly, a bunch of the ASN.1 stuff) treats these parameters as > >> variable-size integers. > > > > But the test uses a static key. It used to generate a key on fly but > > IMO even though the test code, it comes from the linux kernel, meaning > that its quality has a certain guarantee and it is a good reference, so > the test code still needs to ensure its correctness. Hmm... what is working incorrectly then? /Jarkko