| Message ID | 2595b4f6ce49cc3d413c75f86a63ad9d26f0f1fd.camel@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [GIT,PULL] tpmdd updates for Linux v5.3 | expand |
The pull request you sent on Thu, 27 Jun 2019 01:50:47 +0300:
> git://git.infradead.org/users/jjs/linux-tpmdd.git tags/tpmdd-next-20190625
has been merged into torvalds/linux.git:
https://git.kernel.org/torvalds/c/884922591e2b58fd7f1018701f957446d1ffac4d
Thank you!
Hi, My v5.3 PR contains two critical bug fixes and support for obtaining TPM events triggered by ExitBootServices(). For the latter I have to give a quite verbose explanation not least because I had to revisit all the details myself to remember what was going on in Matthew's patches. The preboot software stack maintains an event log that gets entries every time something gets hashed to any of the PCR registers. What gets hashed could be a component to be run or perhaps log of some actions taken just to give couple of coarse examples. In general, anything relevant for the boot process that the preboot software does gets hashed and a log entry with a specific event type [1]. The main application for this is remote attestation and the reason why it is useful is nicely put in the very first section of [1]: "Attestation is used to provide information about the platform’s state to a challenger. However, PCR contents are difficult to interpret; therefore, attestation is typically more useful when the PCR contents are accompanied by a measurement log. While not trusted on their own, the measurement log contains a richer set of information than do the PCR contents. The PCR contents are used to provide the validation of the measurement log." Because EFI_TCG2_PROTOCOL.GetEventLog() is not available after calling ExitBootServices(), Linux EFI stub copies the event log to a custom configuration table. Unfortunately, ExitBootServices() also generates events and obviously these events do not get copied to that table. Luckily firmware does this for us by providing a configuration table identified by EFI_TCG2_FINAL_EVENTS_TABLE_GUID. This PR essentially contains necessary changes to provide the full event log for the use the user space that is concatenated from these two partial event logs [2]. [1] https://trustedcomputinggroup.org/resource/pc-client-specific-platform-firmware-profile-specification/ [2] The final concatenation is done in drivers/char/tpm/eventlog/efi.c /Jarkko The following changes since commit c88e40e07cd967dcdf37321a63ab6e8b0d881100: Merge tag 'mfd-fixes-5.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd (2019-06-25 03:41:03 +0800) are available in the Git repository at: git://git.infradead.org/users/jjs/linux-tpmdd.git tags/tpmdd-next-20190625 for you to fetch changes up to 166a2809d65b282272c474835ec22c882a39ca1b: tpm: Don't duplicate events from the final event log in the TCG2 log (2019-06- 24 23:57:50 +0300) ---------------------------------------------------------------- tpmdd updates for Linux v5.3 ---------------------------------------------------------------- Kees Cook (1): tpm: Actually fail on TPM errors during "get random" Matthew Garrett (6): tpm: Abstract crypto agile event size calculations tpm: Reserve the TPM final events table tpm: Append the final event log to the TPM event log efi: Attempt to get the TCG2 event log in the boot stub Abstract out support for locating an EFI config table tpm: Don't duplicate events from the final event log in the TCG2 log Vadim Sukhomlinov (1): tpm: Fix TPM 1.2 Shutdown sequence to prevent future TPM operations drivers/char/tpm/eventlog/efi.c | 59 ++++++++-- drivers/char/tpm/eventlog/tpm2.c | 47 +------- drivers/char/tpm/tpm-chip.c | 6 +- drivers/char/tpm/tpm1-cmd.c | 7 +- drivers/char/tpm/tpm2-cmd.c | 7 +- drivers/firmware/efi/efi.c | 2 + drivers/firmware/efi/libstub/efi-stub-helper.c | 15 +++ drivers/firmware/efi/libstub/efistub.h | 2 + drivers/firmware/efi/libstub/fdt.c | 27 ++--- drivers/firmware/efi/libstub/tpm.c | 80 ++++++++++--- drivers/firmware/efi/tpm.c | 63 +++++++++- include/linux/efi.h | 10 ++ include/linux/tpm_eventlog.h | 152 +++++++++++++++++++++++++ 13 files changed, 378 insertions(+), 99 deletions(-)