Add columns for snapshot table

Currently snapshots are held in memory, meaning they must be regenerated
if a reboot occurs before a key sync. Also, when debugging, it is
difficult to know what version of e.g. the server params was associated
with a particular snapshot, as this can be mutated after the snapshot is
generated. This change adds the required columns to the DB contract for
storing snapshots. In subsequent CLs the update SQL will be added.

Test: none, no functionality added
Change-Id: Ica866b06950a5801e8a2c3641e79706bbbf48384

diff --git a/services/core/java/com/android/server/locksettings/recoverablekeystore/storage/RecoverableKeyStoreDbContract.java b/services/core/java/com/android/server/locksettings/recoverablekeystore/storage/RecoverableKeyStoreDbContract.java
index 1cb5d91..8983ec3 100644 (file)
--- a/services/core/java/com/android/server/locksettings/recoverablekeystore/storage/RecoverableKeyStoreDbContract.java
+++ b/services/core/java/com/android/server/locksettings/recoverablekeystore/storage/RecoverableKeyStoreDbContract.java
@@ -70,6 +70,122 @@ class RecoverableKeyStoreDbContract {
     }
 
     /**
+     * Table holding encrypted snapshots of the recoverable key store.
+     */
+    static class SnapshotsEntry implements BaseColumns {
+        static final String TABLE_NAME = "snapshots";
+
+        /**
+         * The version number of the snapshot.
+         */
+        static final String COLUMN_NAME_VERSION = "version";
+
+        /**
+         * The ID of the user whose keystore was snapshotted.
+         */
+        static final String COLUMN_NAME_USER_ID = "user_id";
+
+        /**
+         * The UID of the app that owns the snapshot (i.e., the recovery agent).
+         */
+        static final String COLUMN_NAME_UID = "uid";
+
+        /**
+         * The maximum number of attempts allowed to attempt to decrypt the recovery key.
+         */
+        static final String COLUMN_NAME_MAX_ATTEMPTS = "max_attempts";
+
+        /**
+         * The ID of the counter in the trusted hardware module.
+         */
+        static final String COLUMN_NAME_COUNTER_ID = "counter_id";
+
+        /**
+         * Server parameters used to help identify the device (during recovery).
+         */
+        static final String SERVER_PARAMS = "server_params";
+
+        /**
+         * The public key of the trusted hardware module. This key has been used to encrypt the
+         * snapshot, to ensure that it can only be read by the trusted module.
+         */
+        static final String TRUSTED_HARDWARE_PUBLIC_KEY = "thm_public_key";
+
+        /**
+         * {@link java.security.cert.CertPath} signing the trusted hardware module to whose public
+         * key this snapshot is encrypted.
+         */
+        static final String CERT_PATH = "cert_path";
+
+        /**
+         * The recovery key, encrypted with the user's lock screen and the trusted hardware module's
+         * public key.
+         */
+        static final String ENCRYPTED_RECOVERY_KEY = "encrypted_recovery_key";
+    }
+
+    /**
+     * Table holding encrypted keys belonging to a particular snapshot.
+     */
+    static class SnapshotKeysEntry implements BaseColumns {
+        static final String TABLE_NAME = "snapshot_keys";
+
+        /**
+         * ID of the associated snapshot entry in {@link SnapshotsEntry}.
+         */
+        static final String COLUMN_NAME_SNAPSHOT_ID = "snapshot_id";
+
+        /**
+         * Alias of the key.
+         */
+        static final String COLUMN_NAME_ALIAS = "alias";
+
+        /**
+         * Key material, encrypted with the recovery key from the snapshot.
+         */
+        static final String COLUMN_NAME_ENCRYPTED_BYTES = "encrypted_key_bytes";
+    }
+
+    /**
+     * A layer of protection associated with a snapshot.
+     */
+    static class SnapshotProtectionParams implements BaseColumns {
+        static final String TABLE_NAME = "snapshot_protection_params";
+
+        /**
+         * ID of the associated snapshot entry in {@link SnapshotsEntry}.
+         */
+        static final String COLUMN_NAME_SNAPSHOT_ID = "snapshot_id";
+
+        /**
+         * Type of secret used to generate recovery key. One of
+         * {@link android.security.keystore.recovery.KeyChainProtectionParams#TYPE_LOCKSCREEN} or
+         * {@link android.security.keystore.recovery.KeyChainProtectionParams#TYPE_CUSTOM_PASSWORD}.
+         */
+        static final String COLUMN_NAME_SECRET_TYPE = "secret_type";
+
+        /**
+         * If a lock screen, the type of UI used. One of
+         * {@link android.security.keystore.recovery.KeyChainProtectionParams#UI_FORMAT_PATTERN},
+         * {@link android.security.keystore.recovery.KeyChainProtectionParams#UI_FORMAT_PIN}, or
+         * {@link android.security.keystore.recovery.KeyChainProtectionParams#UI_FORMAT_PASSWORD}.
+         */
+        static final String COLUMN_NAME_LOCKSCREEN_UI_TYPE = "lock_screen_ui_type";
+
+        /**
+         * The algorithm used to derive cryptographic material from the key and salt. One of
+         * {@link android.security.keystore.recovery.KeyDerivationParams#ALGORITHM_SHA256} or
+         * {@link android.security.keystore.recovery.KeyDerivationParams#ALGORITHM_ARGON2ID}.
+         */
+        static final String COLUMN_NAME_KEY_DERIVATION_ALGORITHM = "key_derivation_algorithm";
+
+        /**
+         * The salt used along with the secret to generate cryptographic material.
+         */
+        static final String COLUMN_NAME_KEY_DERIVATION_SALT = "key_derivation_salt";
+    }
+
+    /**
      * Recoverable KeyStore metadata for a specific user profile.
      */
     static class UserMetadataEntry implements BaseColumns {