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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 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 DEA38C3F2D1 for ; Mon, 2 Mar 2020 14:46:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B452D2166E for ; Mon, 2 Mar 2020 14:46:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727159AbgCBOqo (ORCPT ); Mon, 2 Mar 2020 09:46:44 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:22996 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727032AbgCBOqo (ORCPT ); Mon, 2 Mar 2020 09:46:44 -0500 Received: from pps.filterd (m0098416.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 022EjKFZ192922 for ; Mon, 2 Mar 2020 09:46:42 -0500 Received: from e06smtp04.uk.ibm.com (e06smtp04.uk.ibm.com [195.75.94.100]) by mx0b-001b2d01.pphosted.com with ESMTP id 2yfjf3y9pd-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 02 Mar 2020 09:46:42 -0500 Received: from localhost by e06smtp04.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Mon, 2 Mar 2020 14:46:37 -0000 Received: from d06av21.portsmouth.uk.ibm.com (d06av21.portsmouth.uk.ibm.com [9.149.105.232]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 022EkarV55705680 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 2 Mar 2020 14:46:36 GMT Received: from d06av21.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 248075204F; Mon, 2 Mar 2020 14:46:36 +0000 (GMT) Received: from localhost.localdomain (unknown [9.80.229.179]) by d06av21.portsmouth.uk.ibm.com (Postfix) with ESMTP id 105105204E; Mon, 2 Mar 2020 14:46:34 +0000 (GMT) Subject: Re: [PATCH v3 2/8] ima: Switch to ima_hash_algo for boot aggregate From: Mimi Zohar To: Roberto Sassu , "James.Bottomley@HansenPartnership.com" , "jarkko.sakkinen@linux.intel.com" , Dmitry Kasatkin Cc: "linux-integrity@vger.kernel.org" , "linux-security-module@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Silviu Vlasceanu , "stable@vger.kernel.org" Date: Mon, 02 Mar 2020 09:46:34 -0500 In-Reply-To: <8a6fb34e18b147fa811e82c78fb30d66@huawei.com> References: <20200210100048.21448-1-roberto.sassu@huawei.com> <20200210100048.21448-3-roberto.sassu@huawei.com> <1581373420.5585.920.camel@linux.ibm.com> <6955307747034265bd282bf68c368f34@huawei.com> <1583156506.8544.60.camel@linux.ibm.com> <8a6fb34e18b147fa811e82c78fb30d66@huawei.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.20.5 (3.20.5-1.fc24) Mime-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 x-cbid: 20030214-0016-0000-0000-000002EC4EF2 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 20030214-0017-0000-0000-0000334F91DB Message-Id: <1583160394.8544.89.camel@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.572 definitions=2020-03-02_04:2020-03-02,2020-03-02 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 suspectscore=0 malwarescore=0 bulkscore=0 phishscore=0 mlxscore=0 mlxlogscore=999 clxscore=1015 impostorscore=0 spamscore=0 adultscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2003020105 Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: > > > > On Mon, 2020-02-10 at 11:00 +0100, Roberto Sassu wrote: > > My initial patch attempted to use any common TPM and kernel hash > > algorithm to calculate the boot_aggregate.  The discussion with James > > was pretty clear, which you even stated in the Changelog.  Either we > > use the IMA default hash algorithm, SHA256 for TPM 2.0 or SHA1 for TPM > > 1.2 for the boot-aggregate. > > Ok, I didn't understand fully. I thought we should use the default IMA > algorithm and select SHA256 as fallback choice for TPM 2.0 if there is no > PCR bank for default algorithm. Yes, preference is given to the IMA default algorithm, but it should fall back to using SHA256 or SHA1, based on the TPM. > I additionally implemented the logic to > select the first PCR bank if the SHA256 PCR bank is not available but I can > remove it. > > SHA256 should be the minimum requirement for boot aggregate. The > advantage of using the default IMA algorithm is that it will be possible to > select stronger algorithms when they are supported by the TPM. We might > introduce a new option to specify only the algorithm for boot aggregate, > like James suggested to support embedded systems. Let me know which > option you prefer. I don't remember James saying that, but if the community really wants that support, then it should be upstreamed independently, as a separate patch.  Let's first get the basics working. thanks, Mimi