[PATCH v3] ima: add a new CONFIG for loading arch-specific policies

[Nayna]

Oops,  Please ignore this patch.

By mistake I posted the wrong version. I am sorry for the confusion,  I 
will resend the right version.

Thanks & Regards,

      - Nayna

On 3/6/20 12:39 PM, Nayna Jain wrote:
> 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 at linux-foundation.org>
> Signed-off-by: Nayna Jain <nayna at linux.ibm.com>
> Cc: Ard Biesheuvel <ardb at kernel.org>
> Cc: Philipp Rudo <prudo at linux.ibm.com>
> Cc: Michael Ellerman <mpe at ellerman.id.au>
> ---
> v3:
> * Updated and tested the patch with improvements suggested by Michael.
> It now uses "imply" instead of "select". Thanks Michael.
> * Have missed replacing the CONFIG_IMA in x86 and s390 with new config,
> that was resulting in redefinition when the IMA_SECURE_AND_OR_TRUSTED_BOOT
> is not enabled. Thanks to Mimi for recognizing the problem.
>
> 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       | 2 +-
>   include/linux/ima.h            | 3 +--
>   security/integrity/ima/Kconfig | 8 ++++++++
>   7 files changed, 14 insertions(+), 4 deletions(-)
>
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index 497b7d0b2d7e..a5cfde432983 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
> +	select 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..4a502fbcb800 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
> +	select IMA_SECURE_AND_OR_TRUSTED_BOOT if IMA_ARCH_POLICY
>   
>   
>   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-$(CONFIG_PERF_EVENTS)	+= perf_cpum_cf.o perf_cpum_sf.o
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index beea77046f9b..7f5bfaf0cbd2 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -230,6 +230,7 @@ config X86
>   	select VIRT_TO_BUS
>   	select X86_FEATURE_NAMES		if PROC_FS
>   	select PROC_PID_ARCH_STATUS		if PROC_FS
> +	select IMA_SECURE_AND_OR_TRUSTED_BOOT	if EFI && IMA_ARCH_POLICY
>   
>   config INSTRUCTION_DECODER
>   	def_bool y
> diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
> index 9b294c13809a..7f131ceba136 100644
> --- a/arch/x86/kernel/Makefile
> +++ b/arch/x86/kernel/Makefile
> @@ -155,5 +155,5 @@ ifeq ($(CONFIG_X86_64),y)
>   endif
>   
>   ifdef CONFIG_EFI
> -obj-$(CONFIG_IMA)			+= ima_arch.o
> +obj-$(CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT)	+= ima_arch.o
>   endif
> 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..2baaf196c6d8 100644
> --- a/security/integrity/ima/Kconfig
> +++ b/security/integrity/ima/Kconfig
> @@ -327,3 +327,11 @@ 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
> +	default n
> +	help
> +	   This option is selected by architectures to enable secure and/or
> +	   trusted boot based on IMA runtime policies.