From mboxrd@z Thu Jan 1 00:00:00 1970 From: nayna@linux.vnet.ibm.com (Nayna Jain) Date: Wed, 26 Sep 2018 17:52:05 +0530 Subject: [PATCH v4 1/6] x86/ima: define arch_ima_get_secureboot In-Reply-To: <20180926122210.14642-1-nayna@linux.vnet.ibm.com> References: <20180926122210.14642-1-nayna@linux.vnet.ibm.com> Message-ID: <20180926122210.14642-2-nayna@linux.vnet.ibm.com> To: linux-security-module@vger.kernel.org List-Id: linux-security-module.vger.kernel.org Distros are concerned about totally disabling the kexec_load syscall. As a compromise, the kexec_load syscall will only be disabled when CONFIG_KEXEC_VERIFY_SIG is configured and the system is booted with secureboot enabled. This patch defines the new arch specific function called arch_ima_get_secureboot() to retrieve the secureboot state of the system. Signed-off-by: Nayna Jain Suggested-by: Seth Forshee --- arch/x86/kernel/Makefile | 2 ++ arch/x86/kernel/ima_arch.c | 17 +++++++++++++++++ include/linux/ima.h | 9 +++++++++ 3 files changed, 28 insertions(+) create mode 100644 arch/x86/kernel/ima_arch.c diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 02d6f5cf4e70..f32406e51424 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -149,3 +149,5 @@ ifeq ($(CONFIG_X86_64),y) obj-$(CONFIG_MMCONF_FAM10H) += mmconf-fam10h_64.o obj-y += vsmp_64.o endif + +obj-$(CONFIG_IMA) += ima_arch.o diff --git a/arch/x86/kernel/ima_arch.c b/arch/x86/kernel/ima_arch.c new file mode 100644 index 000000000000..bb5a88d2b271 --- /dev/null +++ b/arch/x86/kernel/ima_arch.c @@ -0,0 +1,17 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Copyright (C) 2018 IBM Corporation + */ +#include +#include + +extern struct boot_params boot_params; + +bool arch_ima_get_secureboot(void) +{ + if (efi_enabled(EFI_BOOT) && + (boot_params.secure_boot == efi_secureboot_mode_enabled)) + return true; + else + return false; +} diff --git a/include/linux/ima.h b/include/linux/ima.h index 84806b54b50a..4852255aa4f4 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -30,6 +30,15 @@ extern void ima_post_path_mknod(struct dentry *dentry); extern void ima_add_kexec_buffer(struct kimage *image); #endif +#ifdef CONFIG_X86 +extern bool arch_ima_get_secureboot(void); +#else +static inline bool arch_ima_get_secureboot(void) +{ + return false; +} +#endif + #else static inline int ima_bprm_check(struct linux_binprm *bprm) { -- 2.13.6