tree 5bbe1097c1e55a42d7af5f21b72e42db2914c298
parent e4db7c02ff8913df0b90445058d8c02e0f14cad6
author Wenhao Wang <wenhaowang@google.com> 1589098407 -0700
committer Wenhao Wang <wenhaowang@google.com> 1600454616 -0700

storage: Support RPMB key provisioning

If the RPMB device has not been programmed with a RPMB key,
a 32 bytes random number is generated. The number is used to
derive a RPMB key with which the RPMB device is programmed.
The random number is written into the first block of the device.

For the situation where the RPMB device has been programmed,
the 32 bytes random number is read from the device.
The RPMB key can be re-derived with the random number.

Bug: 152901318
Change-Id: I91487bfdacb66d18081088b657ba23f4f6e67fd8