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=-6.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 2DD1AC67839 for ; Wed, 12 Dec 2018 18:15:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E53342084E for ; Wed, 12 Dec 2018 18:15:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E53342084E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-integrity-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728220AbeLLSPH (ORCPT ); Wed, 12 Dec 2018 13:15:07 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:36796 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728213AbeLLSPH (ORCPT ); Wed, 12 Dec 2018 13:15:07 -0500 Received: from pps.filterd (m0098414.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id wBCIDbmn060550 for ; Wed, 12 Dec 2018 13:15:06 -0500 Received: from e34.co.us.ibm.com (e34.co.us.ibm.com [32.97.110.152]) by mx0b-001b2d01.pphosted.com with ESMTP id 2pb6uvhs25-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Wed, 12 Dec 2018 13:15:05 -0500 Received: from localhost by e34.co.us.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) Wed, 12 Dec 2018 18:15:01 -0000 Received: from b03ledav005.gho.boulder.ibm.com (b03ledav005.gho.boulder.ibm.com [9.17.130.236]) by b03cxnp08025.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id wBCIF0rP29032522 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Wed, 12 Dec 2018 18:15:00 GMT Received: from b03ledav005.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 338D0BE051; Wed, 12 Dec 2018 18:15:00 +0000 (GMT) Received: from b03ledav005.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id CEBEBBE04F; Wed, 12 Dec 2018 18:14:52 +0000 (GMT) Received: from morokweng.localdomain (unknown [9.85.201.40]) by b03ledav005.gho.boulder.ibm.com (Postfix) with ESMTPS; Wed, 12 Dec 2018 18:14:52 +0000 (GMT) References: <20181208202705.18673-1-nayna@linux.ibm.com> <20181208202705.18673-8-nayna@linux.ibm.com> User-agent: mu4e 1.0; emacs 26.1 From: Thiago Jung Bauermann To: Nayna Jain Cc: linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, zohar@linux.ibm.com, dhowells@redhat.com, jforbes@redhat.com, seth.forshee@canonical.com, kexec@lists.infradead.org, keyrings@vger.kernel.org, vgoyal@redhat.com, ebiederm@xmission.com, mpe@ellerman.id.au Subject: Re: [PATCH v2 7/7] ima: Support platform keyring for kernel appraisal In-reply-to: <20181208202705.18673-8-nayna@linux.ibm.com> Date: Wed, 12 Dec 2018 16:14:47 -0200 MIME-Version: 1.0 Content-Type: text/plain X-TM-AS-GCONF: 00 x-cbid: 18121218-0016-0000-0000-000009637388 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00010215; HX=3.00000242; KW=3.00000007; PH=3.00000004; SC=3.00000270; SDB=6.01130792; UDB=6.00587619; IPR=6.00910926; MB=3.00024670; MTD=3.00000008; XFM=3.00000015; UTC=2018-12-12 18:15:04 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18121218-0017-0000-0000-000041619E9B Message-Id: <8736r2fw88.fsf@morokweng.localdomain> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-12-12_04:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1812120156 Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org Hello, Nayna Jain writes: > On secure boot enabled systems, the bootloader verifies the kernel > image and possibly the initramfs signatures based on a set of keys. A > soft reboot(kexec) of the system, with the same kernel image and > initramfs, requires access to the original keys to verify the > signatures. > > This patch allows IMA-appraisal access to those original keys, now > loaded on the platform keyring, needed for verifying the kernel image > and initramfs signatures. > > Signed-off-by: Nayna Jain > Reviewed-by: Mimi Zohar > Acked-by: Serge Hallyn > - replace 'rc' with 'xattr_len' when calling integrity_digsig_verify() > with INTEGRITY_KEYRING_IMA for readability > Suggested-by: Serge Hallyn > --- > Changelog: > > v2: > - replace 'rc' with 'xattr_len' when calling integrity_digsig_verify() > with INTEGRITY_KEYRING_IMA for readability > > security/integrity/ima/ima_appraise.c | 13 +++++++++++-- > 1 file changed, 11 insertions(+), 2 deletions(-) > > diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c > index deec1804a00a..e8f520450895 100644 > --- a/security/integrity/ima/ima_appraise.c > +++ b/security/integrity/ima/ima_appraise.c > @@ -289,12 +289,21 @@ int ima_appraise_measurement(enum ima_hooks func, > case EVM_IMA_XATTR_DIGSIG: > set_bit(IMA_DIGSIG, &iint->atomic_flags); > rc = integrity_digsig_verify(INTEGRITY_KEYRING_IMA, > - (const char *)xattr_value, rc, > + (const char *)xattr_value, > + xattr_len, > iint->ima_hash->digest, > iint->ima_hash->length); > if (rc == -EOPNOTSUPP) { > status = INTEGRITY_UNKNOWN; > - } else if (rc) { > + break; > + } > + if (rc && func == KEXEC_KERNEL_CHECK) > + rc = integrity_digsig_verify(INTEGRITY_KEYRING_PLATFORM, > + (const char *)xattr_value, > + xattr_len, > + iint->ima_hash->digest, > + iint->ima_hash->length); If CONFIG_INTEGRITY_PLATFORM_KEYRING=n the second call to integrity_digsig_verify() above will always fail, and the audit message of failed signature verifications for KEXEC_KERNEL will always log the same rc value, which is whatever request_key() returns when asked to look for an inexistent keyring. Here is a patch which only performs the second try if the platform keyring is enabled. >From d5fb94ab9eb13f6294f8dc44d1344cb85dfa41b8 Mon Sep 17 00:00:00 2001 From: Thiago Jung Bauermann Date: Wed, 12 Dec 2018 16:02:09 -0200 Subject: [PATCH] ima: Only use the platform keyring if it's enabled Signed-off-by: Thiago Jung Bauermann --- security/integrity/ima/ima_appraise.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c index e8f520450895..f6ac405daabb 100644 --- a/security/integrity/ima/ima_appraise.c +++ b/security/integrity/ima/ima_appraise.c @@ -297,7 +297,8 @@ int ima_appraise_measurement(enum ima_hooks func, status = INTEGRITY_UNKNOWN; break; } - if (rc && func == KEXEC_KERNEL_CHECK) + if (IS_ENABLED(CONFIG_INTEGRITY_PLATFORM_KEYRING) && rc && + func == KEXEC_KERNEL_CHECK) rc = integrity_digsig_verify(INTEGRITY_KEYRING_PLATFORM, (const char *)xattr_value, xattr_len,