drm/1.2/IDrmPlugin.hal

/**
 * Copyright (C) 2018 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package android.hardware.drm@1.2;

import @1.1::IDrmPlugin;
import @1.0::Status;

/**
 * IDrmPlugin is used to interact with a specific drm plugin that was created by
 * IDrm::createPlugin. A drm plugin provides methods for obtaining drm keys that
 * may be used by a codec to decrypt protected video content.
 */
interface IDrmPlugin extends @1.1::IDrmPlugin {

    /**
     * The keys in an offline license allow protected content to be
     * played even if the device is not connected to a network.
     * Offline licenses are stored on the device after a key
     * request/response exchange when the key request KeyType is
     * OFFLINE. Normally each app is responsible for keeping track of
     * the KeySetIds it has created. In some situations however, it
     * may be necessary to request the list of stored offline license
     * KeySetIds. If an app loses the KeySetId for any stored licenses
     * that it created, for example, it must be able to recover the
     * stored KeySetIds so those licenses can be removed when they
     * expire or when the app is uninstalled.
     * <p>
     * This method returns a list of the KeySetIds for all offline
     * licenses. The offline license KeySetId may be used to query
     * the status of an offline license or remove it.
     *
     * @return status the status of the call. May be OK or
     *     ERROR_DRM_INVALID_STATE if the HAL is in a state where the
     *     KeySetIds can't be returned.
     * @return a list of offline license keySetIds. If there are no offline
     *     licenses, the list must be empty and OK must be returned as the
     *     status.
     */
    getOfflineLicenseKeySetIds() generates (Status status, vec<KeySetId> keySetIds);

    /**
     * Normally offline licenses are released using a key
     * request/response exchange using getKeyRequest where the KeyType
     * is RELEASE, followed by provideKeyResponse. This allows the
     * server to cryptographically confirm that the license has been
     * removed and then adjust the count of offline licenses allocated
     * to the device.
     * <p>
     * In some exceptional situations it may be necessary to directly
     * remove offline licenses without notifying the server, which may
     * be performed using this method.
     *
     * @param keySetId the id of the offline license to remove
     * @return status the status of the call. May be one of OK on
     *     success, BAD_VALUE if the license is not found or
     *     ERROR_DRM_INVALID_STATE if the HAL is in a state where the
     *     KeySetIds can't be returned.
     */
    removeOfflineLicense(KeySetId keySetId) generates (Status status);

    /**
     * Request the state of an offline license. An offline license may
     * be usable or inactive. The keys in a usable offline license are
     * available for decryption. When the offline license state is
     * inactive, the keys have been marked for release using
     * getKeyRequest with KeyType RELEASE but the key response has not
     * been received. The keys in an inactive offline license are not
     * usable for decryption.
     *
     * @param keySetId the id of the offline license
     * @return status the status of the call. May be one of OK on
     *     success, BAD_VALUE if the license is not found or
     *     ERROR_DRM_INVALID_STATE if the HAL is in a state where the
     *     offline license state can't be queried.
     * @return the offline license state, one of USABLE or INACTIVE.
     *     If the return status is not OK then state must be set to
     *     UNKNOWN.
     */
    getOfflineLicenseState(KeySetId keySetId) generates (Status status,
            OfflineLicenseState state);
};