From patchwork Tue Jun 11 17:06:05 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nayna Jain X-Patchwork-Id: 10987891 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2436776 for ; Tue, 11 Jun 2019 17:06:40 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0E00B28618 for ; Tue, 11 Jun 2019 17:06:40 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 017E22863B; Tue, 11 Jun 2019 17:06:39 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7188228618 for ; Tue, 11 Jun 2019 17:06:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2405821AbfFKRGb (ORCPT ); Tue, 11 Jun 2019 13:06:31 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:41194 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2405814AbfFKRGb (ORCPT ); Tue, 11 Jun 2019 13:06:31 -0400 Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x5BH2iJD059635 for ; Tue, 11 Jun 2019 13:06:30 -0400 Received: from e06smtp07.uk.ibm.com (e06smtp07.uk.ibm.com [195.75.94.103]) by mx0b-001b2d01.pphosted.com with ESMTP id 2t2emjdrm1-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Tue, 11 Jun 2019 13:06:29 -0400 Received: from localhost by e06smtp07.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) Tue, 11 Jun 2019 18:06:24 +0100 Received: from d06av25.portsmouth.uk.ibm.com (d06av25.portsmouth.uk.ibm.com [9.149.105.61]) by b06avi18626390.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x5BH6FWg26214754 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 11 Jun 2019 17:06:16 GMT Received: from d06av25.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id AD24D11C05E; Tue, 11 Jun 2019 17:06:22 +0000 (GMT) Received: from d06av25.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 23A1011C04C; Tue, 11 Jun 2019 17:06:20 +0000 (GMT) Received: from swastik.ibm.com (unknown [9.80.199.191]) by d06av25.portsmouth.uk.ibm.com (Postfix) with ESMTP; Tue, 11 Jun 2019 17:06:19 +0000 (GMT) From: Nayna Jain To: linuxppc-dev@ozlabs.org, linux-efi@vger.kernel.org, linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Michael Ellerman , Paul Mackerras , Benjamin Herrenschmidt , Ard Biesheuvel , Jeremy Kerr , Matthew Garret , Mimi Zohar , Claudio Carvalho , Nayna Jain , Satheesh Rajendran Subject: [PATCH v4 3/3] powerpc: Add support to initialize ima policy rules Date: Tue, 11 Jun 2019 13:06:05 -0400 X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1560272765-5768-1-git-send-email-nayna@linux.ibm.com> References: <1560272765-5768-1-git-send-email-nayna@linux.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 19061117-0028-0000-0000-0000037967E0 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19061117-0029-0000-0000-0000243957E4 Message-Id: <1560272765-5768-4-git-send-email-nayna@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-06-11_08:,, 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-1906110109 Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP PowerNV secure boot relies on the kernel IMA security subsystem to perform the OS kernel image signature verification. Since each secure boot mode has different IMA policy requirements, dynamic definition of the policy rules based on the runtime secure boot mode of the system is required. On systems that support secure boot, but have it disabled, only measurement policy rules of the kernel image and modules are defined. This patch defines the arch-specific implementation to retrieve the secure boot mode of the system and accordingly configures the IMA policy rules. This patch provides arch-specific IMA policies if PPC_SECURE_BOOT config is enabled. Signed-off-by: Nayna Jain --- arch/powerpc/Kconfig | 14 +++++++++ arch/powerpc/kernel/Makefile | 1 + arch/powerpc/kernel/ima_arch.c | 54 ++++++++++++++++++++++++++++++++++ include/linux/ima.h | 3 +- 4 files changed, 71 insertions(+), 1 deletion(-) create mode 100644 arch/powerpc/kernel/ima_arch.c diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 8c1c636308c8..9de77bb14f54 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -902,6 +902,20 @@ config PPC_MEM_KEYS If unsure, say y. +config PPC_SECURE_BOOT + prompt "Enable PowerPC Secure Boot" + bool + default n + depends on PPC64 + depends on OPAL_SECVAR + depends on IMA + depends on IMA_ARCH_POLICY + help + Linux on POWER with firmware secure boot enabled needs to define + security policies to extend secure boot to the OS.This config + allows user to enable OS Secure Boot on PowerPC systems that + have firmware secure boot support. + endmenu config ISA_DMA_API diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile index 0ea6c4aa3a20..75c929b41341 100644 --- a/arch/powerpc/kernel/Makefile +++ b/arch/powerpc/kernel/Makefile @@ -131,6 +131,7 @@ ifdef CONFIG_IMA obj-y += ima_kexec.o endif endif +obj-$(CONFIG_PPC_SECURE_BOOT) += ima_arch.o obj-$(CONFIG_AUDIT) += audit.o obj64-$(CONFIG_AUDIT) += compat_audit.o diff --git a/arch/powerpc/kernel/ima_arch.c b/arch/powerpc/kernel/ima_arch.c new file mode 100644 index 000000000000..1767bf6e6550 --- /dev/null +++ b/arch/powerpc/kernel/ima_arch.c @@ -0,0 +1,54 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 IBM Corporation + * Author: Nayna Jain + * + * ima_arch.c + * - initialize ima policies for PowerPC Secure Boot + */ + +#include +#include + +bool arch_ima_get_secureboot(void) +{ + bool sb_mode; + + sb_mode = get_powerpc_sb_mode(); + if (sb_mode) + return true; + else + return false; +} + +/* + * File signature verification is not needed, include only measurements + */ +static const char *const default_arch_rules[] = { + "measure func=KEXEC_KERNEL_CHECK template=ima-modsig", + "measure func=MODULE_CHECK template=ima-modsig", + NULL +}; + +/* Both file signature verification and measurements are needed */ +static const char *const sb_arch_rules[] = { + "measure func=KEXEC_KERNEL_CHECK template=ima-modsig", + "measure func=MODULE_CHECK template=ima-modsig", + "appraise func=KEXEC_KERNEL_CHECK appraise_type=imasig|modsig template=ima-modsig", +#if !IS_ENABLED(CONFIG_MODULE_SIG) + "appraise func=MODULE_CHECK appraise_type=imasig|modsig template=ima-modsig", +#endif + NULL +}; + +/* + * On PowerPC, file measurements are to be added to the IMA measurement list + * irrespective of the secure boot state of the system. Signature verification + * is conditionally enabled based on the secure boot state. + */ +const char *const *arch_get_ima_policy(void) +{ + if (IS_ENABLED(CONFIG_IMA_ARCH_POLICY) && arch_ima_get_secureboot()) + return sb_arch_rules; + return default_arch_rules; +} diff --git a/include/linux/ima.h b/include/linux/ima.h index fd9f7cf4cdf5..a01df076ecae 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -31,7 +31,8 @@ extern void ima_post_path_mknod(struct dentry *dentry); extern void ima_add_kexec_buffer(struct kimage *image); #endif -#if (defined(CONFIG_X86) && defined(CONFIG_EFI)) || defined(CONFIG_S390) +#if (defined(CONFIG_X86) && defined(CONFIG_EFI)) || defined(CONFIG_S390) \ + || defined(CONFIG_PPC_SECURE_BOOT) extern bool arch_ima_get_secureboot(void); extern const char * const *arch_get_ima_policy(void); #else