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=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 autolearn=unavailable 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 D3986C433DF for ; Tue, 23 Jun 2020 14:03:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B8CBB20723 for ; Tue, 23 Jun 2020 14:03:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732760AbgFWODs (ORCPT ); Tue, 23 Jun 2020 10:03:48 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:36534 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732727AbgFWODs (ORCPT ); Tue, 23 Jun 2020 10:03:48 -0400 Received: from pps.filterd (m0098396.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 05NE21rl132386; Tue, 23 Jun 2020 10:03:38 -0400 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 31ue3dtgsg-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 23 Jun 2020 10:03:38 -0400 Received: from m0098396.ppops.net (m0098396.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 05NE2Cws133248; Tue, 23 Jun 2020 10:03:37 -0400 Received: from ppma04ams.nl.ibm.com (63.31.33a9.ip4.static.sl-reverse.com [169.51.49.99]) by mx0a-001b2d01.pphosted.com with ESMTP id 31ue3dtgqy-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 23 Jun 2020 10:03:37 -0400 Received: from pps.filterd (ppma04ams.nl.ibm.com [127.0.0.1]) by ppma04ams.nl.ibm.com (8.16.0.42/8.16.0.42) with SMTP id 05NE0qW5022671; Tue, 23 Jun 2020 14:03:34 GMT Received: from b06cxnps3074.portsmouth.uk.ibm.com (d06relay09.portsmouth.uk.ibm.com [9.149.109.194]) by ppma04ams.nl.ibm.com with ESMTP id 31uk4mg031-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 23 Jun 2020 14:03:34 +0000 Received: from d06av24.portsmouth.uk.ibm.com (d06av24.portsmouth.uk.ibm.com [9.149.105.60]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 05NE3WJe34865156 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 23 Jun 2020 14:03:32 GMT Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 3525E42049; Tue, 23 Jun 2020 14:03:32 +0000 (GMT) Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 2D34242056; Tue, 23 Jun 2020 14:03:11 +0000 (GMT) Received: from localhost.localdomain (unknown [9.80.212.185]) by d06av24.portsmouth.uk.ibm.com (Postfix) with ESMTP; Tue, 23 Jun 2020 14:03:11 +0000 (GMT) Message-ID: <1592920990.5437.15.camel@linux.ibm.com> Subject: Re: [PATCH] ima: extend boot_aggregate with kernel measurements From: Mimi Zohar To: Maurizio Drocco Cc: Silviu.Vlasceanu@huawei.com, dmitry.kasatkin@gmail.com, jejb@linux.ibm.com, jmorris@namei.org, linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, mdrocco@linux.vnet.ibm.com, roberto.sassu@huawei.com, serge@hallyn.com Date: Tue, 23 Jun 2020 10:03:10 -0400 In-Reply-To: <20200622045019.1636-1-maurizio.drocco@ibm.com> References: <1592856871.4987.21.camel@linux.ibm.com> <20200622045019.1636-1-maurizio.drocco@ibm.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-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.216,18.0.687 definitions=2020-06-23_06:2020-06-23,2020-06-23 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 mlxlogscore=999 impostorscore=0 cotscore=-2147483648 adultscore=0 mlxscore=0 bulkscore=0 lowpriorityscore=0 clxscore=1015 priorityscore=1501 phishscore=0 suspectscore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2006230108 Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: Hi Maurizio, When re-posting patches, please include the version number (e.g. [PATCH v4] ima: ... ). On Mon, 2020-06-22 at 00:50 -0400, Maurizio Drocco wrote: > IMA is not considering TPM registers 8-9 when calculating the boot > aggregate. This line is unnecessary with the following change. > When registers 8-9 are used to store measurements of the > kernel and its command line (e.g., grub2 bootloader with tpm module > enabled), IMA should include them in the boot aggregate. The "When" clause makes this sound like PCRs 8 & 9 are not always included.  I would split this into two sentences. > Registers > 8-9 are only included in non-SHA1 boot_aggregate digests to avoid > ambiguity. > > Signed-off-by: Maurizio Drocco > --- Missing "Changelog:". Changelog: v2:  - Limit including PCRs 8 & 9 to non-sha1 hashes v1: - Include non zero PCRs 8 & 9 in the boot_aggregate > security/integrity/ima/ima.h | 2 +- > security/integrity/ima/ima_crypto.c | 15 ++++++++++++++- > 2 files changed, 15 insertions(+), 2 deletions(-) > > diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h > index df93ac258e01..9d94080bdad8 100644 > --- a/security/integrity/ima/ima.h > +++ b/security/integrity/ima/ima.h > @@ -30,7 +30,7 @@ > > enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN, > IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII }; > -enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8 }; > +enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8, TPM_PCR10 = 10 }; > > /* digest size for IMA, fits SHA1 or MD5 */ > #define IMA_DIGEST_SIZE SHA1_DIGEST_SIZE > diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c > index 220b14920c37..d02917d85033 100644 > --- a/security/integrity/ima/ima_crypto.c > +++ b/security/integrity/ima/ima_crypto.c > @@ -823,13 +823,26 @@ static int ima_calc_boot_aggregate_tfm(char *digest, u16 alg_id, > if (rc != 0) > return rc; > > - /* cumulative sha1 over tpm registers 0-7 */ > + /* cumulative digest over tpm registers 0-7 */ Please uppercase "tpm" here and below. > for (i = TPM_PCR0; i < TPM_PCR8; i++) { > ima_pcrread(i, &d); > /* now accumulate with current aggregate */ > rc = crypto_shash_update(shash, d.digest, > crypto_shash_digestsize(tfm)); > } > + /* > + * extend cumulative digest over tpm registers 8-9, which contain > + * measurement for the kernel command line (reg. 8) and image (reg. 9) > + * in a typical PCR allocation. Registers 8-9 are only included in > + * non-SHA1 boot_aggregate digests to avoid ambiguity. > + */ Comments that are full sentences should start with an uppercase letter and end with a period (e.g. Extend). thanks, Mimi > + if (alg_id != TPM_ALG_SHA1) { > + for (i = TPM_PCR8; i < TPM_PCR10; i++) { > + ima_pcrread(i, &d); > + rc = crypto_shash_update(shash, d.digest, > + crypto_shash_digestsize(tfm)); > + } > + } > if (!rc) > crypto_shash_final(shash, digest); > return rc;