Keystore 2.0: Key garbage collection.
This patch introduces a key life cycle state in the keyentry table. We
use this to implement key garbage collection.
This patch:
* Introduces the key lifecycle.
* Database functionality for marking a key unreferenced, getting an
unreferenced key, and purging keys from the database.
* Implements the deleteKey API call of IKeyStoreService.
* Implements async_task, a singke on-demand worker thread.
* Implements a garbage collector that collects unreferenced
keys and disposes off sensitive key material.
* Remove security level from the blobentry table.
Bug: 159340471
Test: keystore2_test
Change-Id: I84ffd64eaae1b86c645b50f100b1b399b9e16e40
7 files changed