update_engine: Add functions for reading/writing TPM values for rollback.
- Adds function to read the minimum allowed kernel key version
ie. crossystem tpm_kernver
- Adds function to set the maximum kernel key version roll forward
value. ie. crossystem max_kernel_rollforward
- Future CL will set max_kernel_rollforward to tpm_kerver as a temporary
measure to preserve the rollback window until server side changes
are made.
BUG=chromium:814090
TEST=FEATURES=test emerge-samus update_engine
Change-Id: I8d0c7db438cbc892745917ad56ea013e87361898
Reviewed-on: https://chromium-review.googlesource.com/927827
Commit-Ready: Zentaro Kavanagh <zentaro@chromium.org>
Tested-by: Zentaro Kavanagh <zentaro@chromium.org>
Reviewed-by: Amin Hassani <ahassani@chromium.org>
Reviewed-by: Sen Jiang <senj@chromium.org>
7 files changed