| Message ID | 20191011003600.22090-1-prsriva@linux.microsoft.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | Add support for arm64 to carry ima measurement | expand |
Hi Prakhar, (You've CC'd a few folk who work for 'arm.org'...) On 11/10/2019 01:35, Prakhar Srivastava wrote: > Add support to carry ima measurement log > to the next kexec'ed session triggered via kexec_file_load. I don't know much about 'ima', I'm assuming its the list of 'stuff' that has already been fed into the TPM as part of SecureBoot. Please forgive the stupid questions, > Currently during kexec the kernel file signatures are/can be validated > prior to actual load, the information(PE/ima signature) is not carried > to the next session. This lead to loss of information. > > Carrying forward the ima measurement log to the next kexec'ed session > allows a verifying party to get the entire runtime event log since the > last full reboot, since that is when PCRs were last reset. Hmm, You're adding this as a linux-specific thing in the chosen node, which points at a memreserve. The question that normally needs answering when adding to the stuff we have to treat as ABI over kexec is: how would this work from a bootloader that isn't kexec? Does it need to work for non-linux OS? Changing anything other than the chosen node of the DT isn't something the kernel should be doing. I suspect if you need reserved memory for this stuff, it should be carved out by the bootloader, and like all other memreserves: should not be moved or deleted. ('fdt_delete_mem_rsv()' is a terrifying idea, we depend on the memreserve nodes to tell use which 'memory' we shouldn't touch!) Sharing with powerpc is a great starting point ... but, how does this work for ACPI systems? How does this work if I keep kexecing between ACPI and DT? I'd prefer it we only had one way this works on arm64, so whatever we do has to cover both. Does ima work without UEFI secure-boot? If not, the Linux-specific UEFI 'memreserve' table might be a better fit, this would be the same for both DT and ACPI systems. Given U-boot supports the UEFI API too, its probably the right thing to do regardless of secure-boot. It looks like x86 doesn't support this either yet. If we have to add something to support ACPI, it would be good if it covers both firmware mechanisms for arm64, and works for x86 in the same way. (How does this thing interact with EFI's existing efi_tpm_eventlog_init()?) Thanks, James
On 10/14/19 11:02 AM, James Morse wrote: > Hi Prakhar, > > (You've CC'd a few folk who work for 'arm.org'...) > > On 11/10/2019 01:35, Prakhar Srivastava wrote: >> Add support to carry ima measurement log >> to the next kexec'ed session triggered via kexec_file_load. > > I don't know much about 'ima', I'm assuming its the list of 'stuff' that has already been > fed into the TPM as part of SecureBoot. Please forgive the stupid questions, > The IMA logs are event logs for module load time signature validation(based on policies) which are backed by the TPM. No SecureBoot information is present in the log other than the boot aggregate. >> Currently during kexec the kernel file signatures are/can be validated >> prior to actual load, the information(PE/ima signature) is not carried >> to the next session. This lead to loss of information. >> >> Carrying forward the ima measurement log to the next kexec'ed session >> allows a verifying party to get the entire runtime event log since the >> last full reboot, since that is when PCRs were last reset. > > Hmm, You're adding this as a linux-specific thing in the chosen node, which points at a > memreserve. > > The question that normally needs answering when adding to the stuff we have to treat as > ABI over kexec is: how would this work from a bootloader that isn't kexec? Does it need to > work for non-linux OS? > This change is only intended to be executed in the path of kexec_file_load and not intended to be executed by any boot loader.(Not very aware of boot loader calls.). The logs are non intended to be injected by the boot loader at all. The change is configurable(CONFIG_IMA_KEXEC) under the IMA subsection and can be disabled if not needed. > Changing anything other than the chosen node of the DT isn't something the kernel should > be doing. I suspect if you need reserved memory for this stuff, it should be carved out by > the bootloader, and like all other memreserves: should not be moved or deleted. > > ('fdt_delete_mem_rsv()' is a terrifying idea, we depend on the memreserve nodes to tell > use which 'memory' we shouldn't touch!) > fdt_delete_mem_rsv - is to cleanup any memory that's been mistakenly still lying around in the same session while creating the fdt. memblock_free is actually used to free up the reserved memory. Thiago may have more insight, This is primarily a code that's been ported from existing kernel for PowerPC. https://github.com/torvalds/linux/blob/master/arch/powerpc/kernel/machine_kexec_file_64.c > > Sharing with powerpc is a great starting point ... but, how does this work for ACPI systems? > How does this work if I keep kexecing between ACPI and DT? > I don't have an answer to this, just going through the call stack i dont believe it depends on ACPI as such. I am not the expert here, but more than willing to try out the scenario in question.(Can you point me to some documentation to setup some environment to test this.) Kexec_file_load call depends purely on DT implementation. > I'd prefer it we only had one way this works on arm64, so whatever we do has to cover both. I can move the code to be only part of arm64 arch if absolutely necessary. Thiago do you have any concerns on going back the path of multiple code paths? > > Does ima work without UEFI secure-boot? Yes, IMA, the measurement is not dependent on any hardware capabilities. TPM is needed to back the measurements but the IMA module will not fail if TPM is not available. In short Secure-boot has no impact on IMA. > If not, the Linux-specific UEFI 'memreserve' table might be a better fit, this would be > the same for both DT and ACPI systems. Given U-boot supports the UEFI API too, its > probably the right thing to do regardless of secure-boot. > > It looks like x86 doesn't support this either yet. If we have to add something to support > ACPI, it would be good if it covers both firmware mechanisms for arm64, and works for x86 > in the same way. > > (How does this thing interact with EFI's existing efi_tpm_eventlog_init()?) > IMA does not interact with the TPM event log. Only one of the PCR's is extended but not logged in the TPM logs. The logging is done in IMA. The IMA measurement log in question is whats needed to be carried over to via kexec_file_load call. I am not sure if i addressed all your concerns, please let me know if i missed anything. To me most concerns look to be towards the kexec case and dependency on hardware(ACPI/TPM) during boot and early boot services, where as carrying the logs is only during the kexec_file_load sys call and does not interfere with that code path. IMA documentation: https://sourceforge.net/p/linux-ima/wiki/Home/ Prakhar Srivastava > > Thanks, > > James >
Hi Prakhar, (CC: +Ard : passing reserved memory between kernels using Kexec?) On 15/10/2019 02:31, prsriva wrote: > On 10/14/19 11:02 AM, James Morse wrote: >> On 11/10/2019 01:35, Prakhar Srivastava wrote: >>> Add support to carry ima measurement log >>> to the next kexec'ed session triggered via kexec_file_load. >> >> I don't know much about 'ima', I'm assuming its the list of 'stuff' that has already been >> fed into the TPM as part of SecureBoot. Please forgive the stupid questions, >> > The IMA logs are event logs for module load time signature validation(based on policies) > which are backed by the TPM. No SecureBoot information is present in the log other than > the boot aggregate. Okay, so SecureBoot is optional with this thing. >>> Currently during kexec the kernel file signatures are/can be validated >>> prior to actual load, the information(PE/ima signature) is not carried >>> to the next session. This lead to loss of information. >>> >>> Carrying forward the ima measurement log to the next kexec'ed session >>> allows a verifying party to get the entire runtime event log since the >>> last full reboot, since that is when PCRs were last reset. >> >> Hmm, You're adding this as a linux-specific thing in the chosen node, which points at a >> memreserve. >> >> The question that normally needs answering when adding to the stuff we have to treat as >> ABI over kexec is: how would this work from a bootloader that isn't kexec? Does it need to >> work for non-linux OS? > This change is only intended to be executed in the path of kexec_file_load and not > intended to be executed by any boot loader.(Not very aware of boot loader calls.). kexec_file_load only means something to the first kernel. If you boot something that isn't linux, does it need to delete this stuff from the DT? Even if you kexec_file_load linux, it could go on to regular-kexec something that is not... what should that do with these things? Other than the chosen node, the DT is treated as a cast-iron description of the platform, we shouldn't be tinkering with it. If its not describing hardware, it probably doesn't belong in the DT. > The logs are non intended to be injected by the boot loader at all. You're using linux as a bootloader with kexec. We have to treat the stuff that gets passed between kernels as ABI, as people expect to be able to kexec to a newer kernel. Is linux-as-a-bootloader special? Or should we work out what any bootloader should do here first. This avoids having to change this when it turns out someone wants to log UEFI DXE-drivers/modules in the TPM too. From the git-log of the ima code it looks like this is some linux-specific format. Are we certain it will never change, and nothing else ever needs to support it? (e.g. the DXE driver example above. Is there another way that sort of thing would work?). > The change is configurable(CONFIG_IMA_KEXEC) under the IMA subsection and can be disabled > if not needed. Sure, but not needed isn't the same as not supported. If we support it at all, we need to cover everything that needs supporting. If its ABI (we treat data passed between kernels as if it is), we need to get it right first time. (my point? We need to get the ACPI story sorted before we add any support... otherwise we end up with two incompatible ways of doing this). [...] >> Sharing with powerpc is a great starting point ... but, how does this work for ACPI >> systems? >> How does this work if I keep kexecing between ACPI and DT? > I don't have an answer to this, just going through the call stack i dont believe it > depends on ACPI as such. I am not the expert here, but more than willing to try out the > scenario in question.(Can you point me to some documentation to setup some environment to > test this.) Yup: Documentation/arm64/arm-acpi.rst Arm64's ACPI support depends on UEFI. As a starter: https://wiki.ubuntu.com/ARM64/QEMU You may need to pass 'acpi=on' on the commandline if your UEFI build supports both DT and ACPI. The x86 name for UEFI-in-Qemu is OVMF, which helps when googling. > Kexec_file_load call depends purely on DT implementation. Heh. And it works with ACPI too! You'll note it only touches things in the chosen node... An ACPI system boots without a DT. Linux's EFI-stub can make API calls and poke around in the UEFI structures to find out about the system. When it finishes, the EFI-stub needs to pass on a set of values to the kernel... we need some kind of key-value store ... To avoid re-inventing the wheel, the EFI-stub creates an empty DT, and shoves the cmdline, the initrd etc in there... just like a DT bootloader would have done. From drivers/firmware/efi/libstub/arm-stub.c::efi_entry() | if (!fdt_addr) | pr_efi(sys_table, "Generating empty DTB\n"); (you will see this message on an ACPI-only system) On an ACPI system there won't be anything else in the DT, other than the chosen node. When booted with UEFI, the memory is described in the UEFI memory-map. An ACPI system doesn't know to look for memreserve nodes in the DT. (it might work by accident, but I wouldn't rely on it). >> I'd prefer it we only had one way this works on arm64, so whatever we do has to cover both. > I can move the code to be only part of arm64 arch if absolutely necessary. Thiago do you > have any concerns on going back the path of multiple code paths? Because arm64 needs to support ACPI too, I think its support for this will always look different to PowerPCs. I think the UEFI persistent-memory-reservations thing is a better fit for this [0][1]. As U-boot supports booting the kernel via the UEFI stub, I think this is all we need to support this. (If your platform supports LPIs, you also need this UEFI table to kexec safely anyway. See [1]) Removing something that was reserved memory might be tricky, I don't think we do this anywhere else. Why do you need to remove the reservations? >> Does ima work without UEFI secure-boot? > Yes, IMA, the measurement is not dependent on any hardware capabilities. > TPM is needed to back the measurements but the IMA module will not fail if TPM is not > available. > In short Secure-boot has no impact on IMA. (thanks) >> If not, the Linux-specific UEFI 'memreserve' table might be a better fit, this would be >> the same for both DT and ACPI systems. Given U-boot supports the UEFI API too, its >> probably the right thing to do regardless of secure-boot. >> >> It looks like x86 doesn't support this either yet. If we have to add something to support >> ACPI, it would be good if it covers both firmware mechanisms for arm64, and works for x86 >> in the same way. >> >> (How does this thing interact with EFI's existing efi_tpm_eventlog_init()?) > IMA does not interact with the TPM event log. > Only one of the PCR's is extended but not logged in the TPM logs. The logging is done in > IMA. The IMA measurement log in question is whats needed to be carried over to via > kexec_file_load call. If SecureBoot isn't relevant, I'm confused as to why kexec_file_load() is. I thought kexec_file_load() only existed because SecureBoot systems need to validate the new OS images's signature before loading it, and we can't trust user-space calling Kexec to do this. If there is no secure boot, why does this thing only work with kexec_file_load()? (good news! With the UEFI memreseve table, it should work transparently with regular kexec too) > I am not sure if i addressed all your concerns, please let me know > if i missed anything. To me most concerns look to be towards the kexec case and dependency > on hardware(ACPI/TPM) during boot and early boot services, where as carrying the logs is > only during the kexec_file_load sys call and does not interfere with that code path. > IMA documentation: https://sourceforge.net/p/linux-ima/wiki/Home/ Supporting ACPI in the same way is something we need to do from day one. kexec_file_load() already does this. I'm not sure "only kexec_file_load()" is a justifiable restriction... Thanks, James [0] https://marc.info/?l=linux-efi&m=153754757208163&w=2 [1] https://lore.kernel.org/lkml/20180921195954.21574-1-marc.zyngier@arm.com/
> I think the UEFI persistent-memory-reservations thing is a better fit for this [0][1].
Hi James,
Thank you for your thought. As I understand you propose the to use the
existing method as such:
1. Use the existing kexec ABI to pass reservation from kernel to
kernel using EFI the same as is done for GICv3 tables.
2. Allow this memory to be reservable only during first Linux boot via
EFI memory reserve
3. Allow to have this memory pre-reserved by firmware or to be
embedded into device tree.
A question I have is how to tell that a reserved region is reserved
for IMA use. With GICv3 it is done by reading the registers, finding
the interrupt tables memory, and check that the memory ranges are
indeed pre-reserved.
Is there a way to name memory with the current ABI that you think is acceptable?
Thank you,
Pasha
On Tue, 15 Oct 2019, James Morse wrote: > > The IMA logs are event logs for module load time signature validation(based on policies) > > which are backed by the TPM. No SecureBoot information is present in the log other than > > the boot aggregate. > > Okay, so SecureBoot is optional with this thing. Correct. Verified boot is one alternative.
Hi James, On Tue, 2019-10-15 at 18:39 +0100, James Morse wrote: > If SecureBoot isn't relevant, I'm confused as to why kexec_file_load() is. > > I thought kexec_file_load() only existed because SecureBoot systems need to validate the > new OS images's signature before loading it, and we can't trust user-space calling Kexec > to do this. > > If there is no secure boot, why does this thing only work with kexec_file_load()? > (good news! With the UEFI memreseve table, it should work transparently with regular kexec > too) I'm so sorry for the confusion. IMA was originally limited to extending trusted boot concepts to the OS. As of Linux 3.10, IMA added support for extending secure boot concepts and auditing file hashes (commit e7c568e0fd0cf). True, kexec_file_load is required for verifying the kexec kernel image, but it is also required for measuring the kexec kernel image as well. After reading the kernel image into memory (kernel_read_file_from_fd), the hash is calculated and then added to the IMA measurement list and used to extend the TPM. All of this is based on the IMA policy, including the TPM PCR. > > > I am not sure if i addressed all your concerns, please let me know > > if i missed anything. To me most concerns look to be towards the kexec case and dependency > > on hardware(ACPI/TPM) during boot and early boot services, where as carrying the logs is > > only during the kexec_file_load sys call and does not interfere with that code path. > > IMA documentation: https://sourceforge.net/p/linux-ima/wiki/Home/ > > Supporting ACPI in the same way is something we need to do from day one. kexec_file_load() > already does this. I'm not sure "only kexec_file_load()" is a justifiable restriction... The TPM PCRs are not reset on a soft reboot. As a result, in order to validate the IMA measurement list against the TPM PCRs, the IMA measurement list is saved on kexec load, restored on boot, and then the memory allocated for carrying the measurement list across kexec is freed. Where/how to save the IMA measurement list is architecture dependent. Thiago Bauermann implemented allocating and freeing the measurement list memory for Power. Mimi
On 10/15/19 11:47 AM, Pavel Tatashin wrote: >> I think the UEFI persistent-memory-reservations thing is a better fit for this [0][1]. > > Hi James, > > Thank you for your thought. As I understand you propose the to use the > existing method as such: > 1. Use the existing kexec ABI to pass reservation from kernel to > kernel using EFI the same as is done for GICv3 tables. > 2. Allow this memory to be reservable only during first Linux boot via > EFI memory reserve > 3. Allow to have this memory pre-reserved by firmware or to be > embedded into device tree. > > A question I have is how to tell that a reserved region is reserved > for IMA use. With GICv3 it is done by reading the registers, finding > the interrupt tables memory, and check that the memory ranges are > indeed pre-reserved. > > Is there a way to name memory with the current ABI that you think is acceptable? > > Thank you, > Pasha > Friendly ping. Thanks, Prakhar Srivastava
Hi Mimi, On 16/10/2019 02:44, Mimi Zohar wrote: > On Tue, 2019-10-15 at 18:39 +0100, James Morse wrote: >> If SecureBoot isn't relevant, I'm confused as to why kexec_file_load() is. >> >> I thought kexec_file_load() only existed because SecureBoot systems need to validate the >> new OS images's signature before loading it, and we can't trust user-space calling Kexec >> to do this. >> >> If there is no secure boot, why does this thing only work with kexec_file_load()? >> (good news! With the UEFI memreseve table, it should work transparently with regular kexec >> too) > I'm so sorry for the confusion. IMA was originally limited to > extending trusted boot concepts to the OS. As of Linux 3.10, IMA > added support for extending secure boot concepts and auditing file > hashes (commit e7c568e0fd0cf). > > True, kexec_file_load is required for verifying the kexec kernel > image, but it is also required for measuring the kexec kernel image as > well. > > After reading the kernel image into memory (kernel_read_file_from_fd), > the hash is calculated and then added to the IMA measurement list and > used to extend the TPM. All of this is based on the IMA policy, > including the TPM PCR. Don't we get a set of segments with the regular kexec syscall? These could equally be hashed and measured, and logged via IMA and/or extending the TPMs measurements. (obviously this would include the command-line and maybe purgatory, which makes it less predictable, but these are still the binary blobs that were given privileged access to the system). >>> I am not sure if i addressed all your concerns, please let me know >>> if i missed anything. To me most concerns look to be towards the kexec case and dependency >>> on hardware(ACPI/TPM) during boot and early boot services, where as carrying the logs is >>> only during the kexec_file_load sys call and does not interfere with that code path. >>> IMA documentation: https://sourceforge.net/p/linux-ima/wiki/Home/ >> >> Supporting ACPI in the same way is something we need to do from day one. kexec_file_load() >> already does this. I'm not sure "only kexec_file_load()" is a justifiable restriction... > The TPM PCRs are not reset on a soft reboot. As a result, in order to > validate the IMA measurement list against the TPM PCRs, the IMA > measurement list is saved on kexec load, restored on boot, and then > the memory allocated for carrying the measurement list across kexec is > freed. Hmm, this is why the reserved memory gets freed. What happens to stuff that happens between kexec-load and boot? There is a comment: | /* segment size can't change between kexec load and execute */ But I can't see anywhere that enforces that. I guess those measurements will go missing, and the TPM value will not match after kexec. Thanks, James
Hi Pavel, On 15/10/2019 19:47, Pavel Tatashin wrote: >> I think the UEFI persistent-memory-reservations thing is a better fit for this [0][1]. > Thank you for your thought. As I understand you propose the to use the > existing method as such: > 1. Use the existing kexec ABI to pass reservation from kernel to > kernel using EFI the same as is done for GICv3 tables. > 2. Allow this memory to be reservable only during first Linux boot via > EFI memory reserve > 3. Allow to have this memory pre-reserved by firmware or to be > embedded into device tree. > > A question I have is how to tell that a reserved region is reserved > for IMA use. With GICv3 it is done by reading the registers, finding > the interrupt tables memory, and check that the memory ranges are > indeed pre-reserved. Good point, efi_mem_reserve_persistent() has no way of describing what a region is for, you have to know that from somewhere else. > Is there a way to name memory with the current ABI that you think is acceptable? This would need to go in the chosen node of the DT, like power-pc already does. This would work on arm64:ACPI systems too (because they have a DT chosen node). I'd like to understand why removing these entries is needed, it doesn't look like we have an API call to remove them from the efi mem-reserve... If it had a fixed position in memory its the sort of thing we'd expect firmware to reserved during boot. (e.g. ramoops). ~ From ima_add_kexec_buffer() this really is a transient memory reservation over kexec. I think the efi mem-reserve and a DT-chosen node entry with the PA is the only way to make this work smoothly between DT<->ACPI systems. We'd need a way of removing the efi mem-reserve in ima_free_kexec_buffer(), otherwise the memory remains lost. The DT-chosen node entry should have its pointer zero'd out once we've done this. (like we do for the KASLR seed). Not considered is parsing the DT-chosen node entry as if it were a memreserve during early boot. This wouldn't work if you kexec something that doesn't know what the node is, it would overwrite the the memory and may not remove the node for the next kexec, which does. Thanks, James
On Fri, 2019-10-25 at 18:07 +0100, James Morse wrote: > Hi Mimi, > > On 16/10/2019 02:44, Mimi Zohar wrote: > > On Tue, 2019-10-15 at 18:39 +0100, James Morse wrote: > >> If SecureBoot isn't relevant, I'm confused as to why kexec_file_load() is. > >> > >> I thought kexec_file_load() only existed because SecureBoot systems need to validate the > >> new OS images's signature before loading it, and we can't trust user-space calling Kexec > >> to do this. > >> > >> If there is no secure boot, why does this thing only work with kexec_file_load()? > >> (good news! With the UEFI memreseve table, it should work transparently with regular kexec > >> too) > > > I'm so sorry for the confusion. IMA was originally limited to > > extending trusted boot concepts to the OS. As of Linux 3.10, IMA > > added support for extending secure boot concepts and auditing file > > hashes (commit e7c568e0fd0cf). > > > > True, kexec_file_load is required for verifying the kexec kernel > > image, but it is also required for measuring the kexec kernel image as > > well. > > > > After reading the kernel image into memory (kernel_read_file_from_fd), > > the hash is calculated and then added to the IMA measurement list and > > used to extend the TPM. All of this is based on the IMA policy, > > including the TPM PCR. > > Don't we get a set of segments with the regular kexec syscall? These could equally be > hashed and measured, and logged via IMA and/or extending the TPMs measurements. IMA works at the file level. I'm not sure what it would mean to measure "segments". Originally, kexec_file_load read the KEXEC kernel image twice, once to calculate the file hash, and again to verify the signature. Now kexec_file_load calls kernel_read_file_from_fd, which reads the file into memory, before IMA calculates the file buffer hash. > > (obviously this would include the command-line and maybe purgatory, which makes it less > predictable, but these are still the binary blobs that were given privileged access to the > system). > > > >>> I am not sure if i addressed all your concerns, please let me know > >>> if i missed anything. To me most concerns look to be towards the kexec case and dependency > >>> on hardware(ACPI/TPM) during boot and early boot services, where as carrying the logs is > >>> only during the kexec_file_load sys call and does not interfere with that code path. > >>> IMA documentation: https://sourceforge.net/p/linux-ima/wiki/Home/ > >> > >> Supporting ACPI in the same way is something we need to do from day one. kexec_file_load() > >> already does this. I'm not sure "only kexec_file_load()" is a justifiable restriction... > > > The TPM PCRs are not reset on a soft reboot. As a result, in order to > > validate the IMA measurement list against the TPM PCRs, the IMA > > measurement list is saved on kexec load, restored on boot, and then > > the memory allocated for carrying the measurement list across kexec is > > freed. > > Hmm, this is why the reserved memory gets freed. Yes > > What happens to stuff that happens between kexec-load and boot? > There is a comment: > | /* segment size can't change between kexec load and execute */ Right, the original version addressed this, but was nixed by Eric, saying it was unnecessary. The current version allocates more memory than needed to hopefully compensate. > > But I can't see anywhere that enforces that. I guess those measurements will go missing, > and the TPM value will not match after kexec. No, the kexec load will succeed, but if there isn't enough memory to store the measurement list, the exec should fail. Mimi
Add support to carry ima measurement log to the next kexec'ed session triggered via kexec_file_load. - Top of Linux 5.3-rc6 Currently during kexec the kernel file signatures are/can be validated prior to actual load, the information(PE/ima signature) is not carried to the next session. This lead to loss of information. Carrying forward the ima measurement log to the next kexec'ed session allows a verifying party to get the entire runtime event log since the last full reboot, since that is when PCRs were last reset. Tested for arm64 qemu and real hardware. I have not been unable to test the patch for powerpc 64bit. Any testing is greatly appretiated. TODO: Add support for 32 bit in the of_ima.c v4: - Fix issue with HAVE_* config wrongly used. v3: - Fix build breaks due to bad config. v2: - move common code to drivers/of/of_ima.c. - point arm64 to use of_ima implementation. - point powerpc to use of_ima implementation v1: - add new fdt porperties to mark start and end for ima measurement log. - use fdt_* functions to add/remove fdt properties and memory allocations. - remove additional check for endian-ness as they are checked in fdt_* functions. v0: - Add support to carry ima measurement log in arm64, uses same code as powerpc. Prakhar Srivastava (2): Add support for arm64 to carry ima measurement log in kexec_file_load update powerpc implementation to call into of_ima* arch/arm64/Kconfig | 1 + arch/arm64/include/asm/ima.h | 24 +++ arch/arm64/include/asm/kexec.h | 5 + arch/arm64/kernel/Makefile | 1 + arch/arm64/kernel/ima_kexec.c | 78 ++++++++++ arch/arm64/kernel/machine_kexec_file.c | 6 + arch/powerpc/include/asm/ima.h | 5 - arch/powerpc/kernel/Makefile | 3 - arch/powerpc/kernel/ima_kexec.c | 170 ++------------------- drivers/of/Kconfig | 6 + drivers/of/Makefile | 1 + drivers/of/of_ima.c | 204 +++++++++++++++++++++++++ include/linux/of.h | 31 ++++ 13 files changed, 371 insertions(+), 164 deletions(-) create mode 100644 arch/arm64/include/asm/ima.h create mode 100644 arch/arm64/kernel/ima_kexec.c create mode 100644 drivers/of/of_ima.c