[RFC PATCH v1 0/4] tsm: Runtime measurement registers ABI

From: Samuel Ortiz
Date: Sun Jan 14 2024 - 17:37:16 EST


Some confidential computing architectures (Intel TDX, ARM CCA, RISC-V
CoVE) provide their guests with a set of measurements registers that can
be extended at runtime, i.e. after the initial, host-initiated
measurements of the TVM are finalized. Those runtime measurement
registers (RTMR) are isolated from the host accessible ones but TSMs
include them in their signed attestation reports.

All architectures supporting RTMRs expose a similar interface to their
TVMs: An extension command/call that takes a measurement value and an
RTMR index to extend it with, and a readback command for reading an RTMR
value back (taking an RTMR index as an argument as well). This patch series
builds an architecture agnostic, configfs-based ABI for userspace to extend
and read RTMR values back. It extends the current TSM ops structure and
each confidential computing architecture can implement this extension to
provide RTMR support.

---
Samuel Ortiz (4):
tsm: Runtime measurement register support
tsm: Add RTMRs to the configfs-tsm hierarchy
tsm: Allow for mapping RTMRs to TCG TPM PCRs
tsm: Allow for extending and reading configured RTMRs

drivers/virt/coco/Kconfig | 1 +
drivers/virt/coco/tsm.c | 362 ++++++++++++++++++++++++++++++++++++++
include/linux/tsm.h | 28 ++-
3 files changed, 390 insertions(+), 1 deletion(-)

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2.42.0