On Fri, Nov 13, 2020 at 11:22:35AM -0800, Lakshmi Ramasubramanian wrote:
> On kexec file load Integrity Measurement Architecture (IMA) subsystem
> may verify the IMA signature of the kernel and initramfs, and measure
> it. The command line parameters passed to the kernel in the kexec call
> may also be measured by IMA. A remote attestation service can verify
> a TPM quote based on the TPM event log, the IMA measurement list, and
> the TPM PCR data. This can be achieved only if the IMA measurement log
> is carried over from the current kernel to the next kernel across
> the kexec call.
>
> powerpc already supports carrying forward the IMA measurement log on
> kexec. This patch set adds support for carrying forward the IMA
> measurement log on kexec on ARM64.
>
> This patch set moves the platform independent code defined for powerpc
> such that it can be reused for other platforms as well. A chosen node
> namely "linux,ima-kexec-buffer" is added to the DTB for ARM64 to hold
> the address and the size of the memory reserved to carry
> the IMA measurement log.
>
> This patch set has been tested for ARM64 platform using QEMU.
> I would like help from the community for testing this change on powerpc.
> Thanks.
As I mentioned previously, please move the kexec code to drivers/of/. Or
at least put the infrastructure in place so we're not defining public
IMA functions and then making them static later.
> This patch set is based on
> commit af5043c89a8e ("Merge tag 'acpi-5.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm")
> in https://github.com/torvalds/linux "master" branch.
>
> Changelog:
>
> v9
> - Moved delete_fdt_mem_rsv() to drivers/of/kexec_fdt.c
> - Defined a new function get_ima_kexec_buffer() in
> drivers/of/ima_kexec.c to replace do_get_kexec_buffer()
> - Changed remove_ima_kexec_buffer() to the original function name
> remove_ima_buffer()
> - Moved remove_ima_buffer() to drivers/of/ima_kexec.c
> - Moved ima_get_kexec_buffer() and ima_free_kexec_buffer()
> to security/integrity/ima/ima_kexec.c
>
> v8:
> - Moved remove_ima_kexec_buffer(), do_get_kexec_buffer(), and
> delete_fdt_mem_rsv() to drivers/of/fdt.c
> - Moved ima_dump_measurement_list() and ima_add_kexec_buffer()
> back to security/integrity/ima/ima_kexec.c
>
> v7:
> - Renamed remove_ima_buffer() to remove_ima_kexec_buffer() and moved
> this function definition to kernel.
> - Moved delete_fdt_mem_rsv() definition to kernel
> - Moved ima_dump_measurement_list() and ima_add_kexec_buffer() to
> a new file namely ima_kexec_fdt.c in IMA
>
> v6:
> - Remove any existing FDT_PROP_IMA_KEXEC_BUFFER property in the device
> tree and also its corresponding memory reservation in the currently
> running kernel.
> - Moved the function remove_ima_buffer() defined for powerpc to IMA
> and renamed the function to ima_remove_kexec_buffer(). Also, moved
> delete_fdt_mem_rsv() from powerpc to IMA.
>
> v5:
> - Merged get_addr_size_cells() and do_get_kexec_buffer() into a single
> function when moving the arch independent code from powerpc to IMA
> - Reverted the change to use FDT functions in powerpc code and added
> back the original code in get_addr_size_cells() and
> do_get_kexec_buffer() for powerpc.
> - Added fdt_add_mem_rsv() for ARM64 to reserve the memory for
> the IMA log buffer during kexec.
> - Fixed the warning reported by kernel test bot for ARM64
> arch_ima_add_kexec_buffer() - moved this function to a new file
> namely arch/arm64/kernel/ima_kexec.c
>
> v4:
> - Submitting the patch series on behalf of the original author
> Prakhar Srivastava <prsriva@xxxxxxxxxxxxxxxxxxx>
> - Moved FDT_PROP_IMA_KEXEC_BUFFER ("linux,ima-kexec-buffer") to
> libfdt.h so that it can be shared by multiple platforms.
>
> v3:
> Breakup patches further into separate patches.
> - Refactoring non architecture specific code out of powerpc
> - Update powerpc related code to use fdt functions
> - Update IMA buffer read related code to use of functions
> - Add support to store the memory information of the IMA
> measurement logs to be carried forward.
> - Update the property strings to align with documented nodes
> https://github.com/devicetree-org/dt-schema/pull/46
>
> v2:
> Break patches into separate patches.
> - Powerpc related Refactoring
> - Updating the docuemntation for chosen node
> - Updating arm64 to support IMA buffer pass
>
> v1:
> Refactoring carrying over IMA measuremnet logs over Kexec. This patch
> moves the non-architecture specific code out of powerpc and adds to
> security/ima.(Suggested by Thiago)
> Add Documentation regarding the ima-kexec-buffer node in the chosen
> node documentation
>
> v0:
> Add a layer of abstraction to use the memory reserved by device tree
> for ima buffer pass.
> Add support for ima buffer pass using reserved memory for arm64 kexec.
> Update the arch sepcific code path in kexec file load to store the
> ima buffer in the reserved memory. The same reserved memory is read
> on kexec or cold boot.
>
> Lakshmi Ramasubramanian (8):
> powerpc: fix compiler warnings and errors
> powerpc: Move delete_fdt_mem_rsv() to drivers/of
> ima: Define get_ima_kexec_buffer() in drivers/of
> powerpc: Use get_ima_kexec_buffer to get ima kexec buffer
> powerpc: Move remove_ima_buffer() to drivers/of
> powerpc: Move ima_get_kexec_buffer() and ima_free_kexec_buffer() to
> ima
> arm64: Store IMA log information in kimage used for kexec
> arm64: Add IMA kexec buffer to DTB
>
> arch/arm64/Kconfig | 1 +
> arch/arm64/include/asm/ima.h | 18 +++++
> arch/arm64/include/asm/kexec.h | 3 +
> arch/arm64/kernel/Makefile | 1 +
> arch/arm64/kernel/ima_kexec.c | 34 ++++++++
> arch/arm64/kernel/machine_kexec_file.c | 18 +++++
> arch/powerpc/include/asm/ima.h | 11 +--
> arch/powerpc/include/asm/kexec.h | 1 -
> arch/powerpc/kexec/Makefile | 7 +-
> arch/powerpc/kexec/file_load.c | 32 --------
> arch/powerpc/kexec/ima.c | 106 ++-----------------------
> drivers/of/Makefile | 9 +++
> drivers/of/ima_kexec.c | 91 +++++++++++++++++++++
> drivers/of/kexec_fdt.c | 55 +++++++++++++
Does this need to be 2 files? Just kexec.c?
> include/linux/kexec.h | 24 ++++++
> security/integrity/ima/ima_kexec.c | 51 ++++++++++++
> 16 files changed, 313 insertions(+), 149 deletions(-)
> create mode 100644 arch/arm64/include/asm/ima.h
> create mode 100644 arch/arm64/kernel/ima_kexec.c
> create mode 100644 drivers/of/ima_kexec.c
> create mode 100644 drivers/of/kexec_fdt.c
>
> --
> 2.29.2
>
