This adds two new flags to crossystem:
clear_tpm_owner_request
clear_tpm_owner_done
The first one requests that the firmware clear the TPM owner on the
next boot. When the firmware does this, it will set
clear_tpm_owner_request=0, and set clear_tpm_owner_done=1. The OS can
use the done-flag as a hint that trusted things guarded by the TPM are
no longer trustable.
BUG=chromium-os:31974
TEST=manual
crossystem
// both flags initially 0
crossystem clear_tpm_owner_request=1
crossystem clear_tpm_owner_done=1
// request=1, done=0; done can be cleared but not set by crossystem
reboot
tpmc getownership
// owned=no
crossystem
// request=0, done=1
crossystem clear_tpm_owner_done=0
crossystem
// both flags 0 again
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Change-Id: I49f83f3c39c3efc3945116c51a241d255c2e42cd
Reviewed-on: https://gerrit.chromium.org/gerrit/25646
29e8807ea0