[PATCH v3] ima: add a new CONFIG for loading arch-specific policies
From: Nayna Jain <nayna@linux.ibm.com>
Date: 2020-03-09 00:58:08
From: Nayna Jain <redacted> Every time a new architecture defines the IMA architecture specific functions - arch_ima_get_secureboot() and arch_ima_get_policy(), the IMA include file needs to be updated. To avoid this "noise", this patch defines a new IMA Kconfig IMA_SECURE_AND_OR_TRUSTED_BOOT option, allowing the different architectures to select it. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Nayna Jain <nayna@linux.ibm.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Philipp Rudo <redacted> Cc: Michael Ellerman <mpe@ellerman.id.au> --- v3: * Removes CONFIG_IMA dependency. Thanks Ard. * Updated the patch with improvements suggested by Michael. It now uses "imply" instead of "select". Thanks Michael. * Replaced the CONFIG_IMA in x86 and s390 with new config, else it was resulting in redefinition when the IMA_SECURE_AND_OR_TRUSTED_BOOT is not enabled. Thanks to Mimi for identifying the problem. * Removed "#ifdef EFI" check in the arch/x86/Makefile for compiling ima_arch.c file. * Ard, Thanks for your Acked-by. I have changed the arch/x86/Makefile in this version. Can you please review again and confirm ? * Rudo, Thanks for your review. I have changed arch/s390/Makefile as well. Can you also please review again ? v2: * Fixed the issue identified by Mimi. Thanks Mimi, Ard, Heiko and Michael for discussing the fix. arch/powerpc/Kconfig | 1 + arch/s390/Kconfig | 1 + arch/s390/kernel/Makefile | 2 +- arch/x86/Kconfig | 1 + arch/x86/kernel/Makefile | 4 +--- include/linux/ima.h | 3 +-- security/integrity/ima/Kconfig | 7 +++++++ 7 files changed, 13 insertions(+), 6 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 497b7d0b2d7e..5b9f1cba2a44 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig@@ -979,6 +979,7 @@ config PPC_SECURE_BOOT bool depends on PPC_POWERNV depends on IMA_ARCH_POLICY + imply IMA_SECURE_AND_OR_TRUSTED_BOOT help Systems with firmware secure boot enabled need to define security policies to extend secure boot to the OS. This config allows a user
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 8abe77536d9d..59c216af6264 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig@@ -195,6 +195,7 @@ config S390 select ARCH_HAS_FORCE_DMA_UNENCRYPTED select SWIOTLB select GENERIC_ALLOCATOR + imply IMA_SECURE_AND_OR_TRUSTED_BOOT config SCHED_OMIT_FRAME_POINTER
diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile
index 2b1203cf7be6..578a6fa82ea4 100644
--- a/arch/s390/kernel/Makefile
+++ b/arch/s390/kernel/Makefile@@ -70,7 +70,7 @@ obj-$(CONFIG_JUMP_LABEL) += jump_label.o obj-$(CONFIG_KEXEC_FILE) += machine_kexec_file.o kexec_image.o obj-$(CONFIG_KEXEC_FILE) += kexec_elf.o -obj-$(CONFIG_IMA) += ima_arch.o +obj-$(CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT) += ima_arch.o obj-$(CONFIG_PERF_EVENTS) += perf_event.o perf_cpum_cf_common.o obj-$(CONFIG_PERF_EVENTS) += perf_cpum_cf.o perf_cpum_sf.o
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index beea77046f9b..dcf5b1729f7c 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig@@ -230,6 +230,7 @@ config X86 select VIRT_TO_BUS select X86_FEATURE_NAMES if PROC_FS select PROC_PID_ARCH_STATUS if PROC_FS + imply IMA_SECURE_AND_OR_TRUSTED_BOOT if EFI config INSTRUCTION_DECODER def_bool y
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 9b294c13809a..cfef37a27def 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile@@ -154,6 +154,4 @@ ifeq ($(CONFIG_X86_64),y) obj-y += vsmp_64.o endif -ifdef CONFIG_EFI -obj-$(CONFIG_IMA) += ima_arch.o -endif +obj-$(CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT) += ima_arch.o
diff --git a/include/linux/ima.h b/include/linux/ima.h
index 1659217e9b60..aefe758f4466 100644
--- a/include/linux/ima.h
+++ b/include/linux/ima.h@@ -30,8 +30,7 @@ extern void ima_kexec_cmdline(const void *buf, int size); extern void ima_add_kexec_buffer(struct kimage *image); #endif -#if (defined(CONFIG_X86) && defined(CONFIG_EFI)) || defined(CONFIG_S390) \ - || defined(CONFIG_PPC_SECURE_BOOT) +#ifdef CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT extern bool arch_ima_get_secureboot(void); extern const char * const *arch_get_ima_policy(void); #else
diff --git a/security/integrity/ima/Kconfig b/security/integrity/ima/Kconfig
index 3f3ee4e2eb0d..edde88dbe576 100644
--- a/security/integrity/ima/Kconfig
+++ b/security/integrity/ima/Kconfig@@ -327,3 +327,10 @@ config IMA_QUEUE_EARLY_BOOT_KEYS depends on IMA_MEASURE_ASYMMETRIC_KEYS depends on SYSTEM_TRUSTED_KEYRING default y + +config IMA_SECURE_AND_OR_TRUSTED_BOOT + bool + depends on IMA_ARCH_POLICY + help + This option is selected by architectures to enable secure and/or + trusted boot based on IMA runtime policies.
--
2.17.1