coreboot/src/security
Julius Werner 74a0fad8a1 security: vboot: Clarify PCR extension algorithms/sizes
The PCR algorithms used for vboot are frequently causing confusion (e.g.
see CB:35645) because depending on the circumstances sometimes a
(zero-extended) SHA1 value is interpreted as a SHA256, and sometimes a
SHA256 is interpreted as a SHA1. We can't really "fix" anything here
because the resulting digests are hardcoded in many generations of
Chromebooks, but we can document and isolate it better to reduce
confusion. This patch adds an explanatory comment and fixes both
algorithms and size passed into the lower-level TPM APIs to their actual
values (whereas it previously still relied on the TPM 1.2 TSS not
checking the algorithm type, and the TPM 2.0 TSS only using the size
value for the TCPA log and not the actual TPM operation).

Signed-off-by: Julius Werner <jwerner@chromium.org>
Change-Id: Ib0b6ecb8c7e9a405ae966f1049158f1d3820f7e2
Reviewed-on: https://review.coreboot.org/c/coreboot/+/51720
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Andrey Pronin <apronin@chromium.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2021-03-30 21:07:56 +00:00
..
intel security/intel/cbnt: Add options to generate BPM from Kconfig 2021-03-30 11:46:33 +00:00
lockdown lockdown: Add hint for how to check for lockdown support in boot log 2020-06-22 12:27:18 +00:00
memory src/security: Drop unneeded empty lines 2020-09-21 16:26:17 +00:00
tpm security/tpm/tss/vendor/cr50: Introduce vendor sub-command to reset EC 2021-03-05 10:57:01 +00:00
vboot security: vboot: Clarify PCR extension algorithms/sizes 2021-03-30 21:07:56 +00:00
Kconfig cbfs: Add verification for RO CBFS metadata hash 2020-12-03 00:11:08 +00:00
Makefile.inc security: Add common boot media write protection 2020-04-28 01:19:32 +00:00