cryptohome: Add checksum to critical persistent files.
Checksum status does not interfere with cryptohome operation but it does
report a metric and any mismatches are logged.
BUG=chromium:554709
TEST=manual: logged in and verified vault files have checksums
TEST=manual: verified metrics are being recorded
TEST=unit
Change-Id: Iafda6be43cffc21837b7e9e9441fe8ec15dc4a47
Previous-Reviewed-on: https://chromium-review.googlesource.com/312718
(cherry picked from commit ba88aa0890fc3f5453f82ce7af9f144fc05b84b6)
Reviewed-on: https://chromium-review.googlesource.com/313469
Reviewed-by: Utkarsh Sanghi <usanghi@chromium.org>
Tested-by: Darren Krahn <dkrahn@chromium.org>
7 files changed
