On Mon, 2 Mar 2020 at 15:48, Mimi Zohar <zohar@xxxxxxxxxxxxx> wrote: > > On Wed, 2020-02-26 at 14:10 -0500, 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@xxxxxxxxxxxxxxxxxxxx> > > Signed-off-by: Nayna Jain <nayna@xxxxxxxxxxxxx> > > Cc: Ard Biesheuvel <ardb@xxxxxxxxxx> > > Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> > > Cc: Philipp Rudo <prudo@xxxxxxxxxxxxx> > > Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> > > --- > > arch/powerpc/Kconfig | 2 +- > > arch/s390/Kconfig | 1 + > > arch/x86/Kconfig | 1 + > > include/linux/ima.h | 3 +-- > > security/integrity/ima/Kconfig | 9 +++++++++ > > 5 files changed, 13 insertions(+), 3 deletions(-) > > > > diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig > > index 497b7d0b2d7e..b8ce1b995633 100644 > > --- a/arch/powerpc/Kconfig > > +++ b/arch/powerpc/Kconfig > > @@ -246,6 +246,7 @@ config PPC > > select SYSCTL_EXCEPTION_TRACE > > select THREAD_INFO_IN_TASK > > select VIRT_TO_BUS if !PPC64 > > + select IMA_SECURE_AND_OR_TRUSTED_BOOT if PPC_SECURE_BOOT > > # > > # Please keep this list sorted alphabetically. > > # > > @@ -978,7 +979,6 @@ config PPC_SECURE_BOOT > > prompt "Enable secure boot support" > > bool > > depends on PPC_POWERNV > > - depends on IMA_ARCH_POLICY > > 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..90ff3633ade6 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 > > > > > > config SCHED_OMIT_FRAME_POINTER > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > > index beea77046f9b..cafa66313fe2 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 > > Not everyone is interested in enabling IMA or requiring IMA runtime > policies. With this patch, enabling IMA_ARCH_POLICY is therefore > still left up to the person building the kernel. As a result, I'm > seeing the following warning, which is kind of cool. > > WARNING: unmet direct dependencies detected for > IMA_SECURE_AND_OR_TRUSTED_BOOT > Depends on [n]: INTEGRITY [=y] && IMA [=y] && IMA_ARCH_POLICY [=n] > Selected by [y]: > - X86 [=y] && EFI [=y] > > Ard, Michael, Martin, just making sure this type of warning is > acceptable before upstreaming this patch. I would appreciate your > tags. > Ehm, no, warnings like these are not really acceptable. It means there is an inconsistency in the way the Kconfig dependencies are defined. Does this help: select IMA_SECURE_AND_OR_TRUSTED_BOOT if EFI && IMA_ARCH_POLICY ? > > > > > config INSTRUCTION_DECODER > > def_bool y > > 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..d17972aa413a 100644 > > --- a/security/integrity/ima/Kconfig > > +++ b/security/integrity/ima/Kconfig > > @@ -327,3 +327,12 @@ 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 > > + 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. > > > >