1 files changed, 607 insertions, 0 deletions
diff --git a/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/drm/DefaultDrmSession.java b/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/drm/DefaultDrmSession.java
new file mode 100644
index 0000000000..ad7ed80580
--- /dev/null
+++ b/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/drm/DefaultDrmSession.java
@@ -0,0 +1,607 @@
+/*
+ * Copyright (C) 2016 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 org.mozilla.thirdparty.com.google.android.exoplayer2.drm;
+
+import android.annotation.SuppressLint;
+import android.annotation.TargetApi;
+import android.media.NotProvisionedException;
+import android.os.Handler;
+import android.os.HandlerThread;
+import android.os.Looper;
+import android.os.Message;
+import android.os.SystemClock;
+import android.util.Pair;
+import androidx.annotation.Nullable;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.C;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.drm.DrmInitData.SchemeData;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.drm.ExoMediaDrm.KeyRequest;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.drm.ExoMediaDrm.ProvisionRequest;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.upstream.LoadErrorHandlingPolicy;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.util.Assertions;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.util.EventDispatcher;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.util.Log;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.util.Util;
+import java.io.IOException;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+import org.checkerframework.checker.nullness.qual.EnsuresNonNullIf;
+import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
+import org.checkerframework.checker.nullness.qual.RequiresNonNull;
+
+/** A {@link DrmSession} that supports playbacks using {@link ExoMediaDrm}. */
+@TargetApi(18)
+/* package */ class DefaultDrmSession<T extends ExoMediaCrypto> implements DrmSession<T> {
+
+  /** Thrown when an unexpected exception or error is thrown during provisioning or key requests. */
+  public static final class UnexpectedDrmSessionException extends IOException {
+
+    public UnexpectedDrmSessionException(Throwable cause) {
+      super("Unexpected " + cause.getClass().getSimpleName() + ": " + cause.getMessage(), cause);
+    }
+  }
+
+  /** Manages provisioning requests. */
+  public interface ProvisioningManager<T extends ExoMediaCrypto> {
+
+    /**
+     * Called when a session requires provisioning. The manager <em>may</em> call {@link
+     * #provision()} to have this session perform the provisioning operation. The manager
+     * <em>will</em> call {@link DefaultDrmSession#onProvisionCompleted()} when provisioning has
+     * completed, or {@link DefaultDrmSession#onProvisionError} if provisioning fails.
+     *
+     * @param session The session.
+     */
+    void provisionRequired(DefaultDrmSession<T> session);
+
+    /**
+     * Called by a session when it fails to perform a provisioning operation.
+     *
+     * @param error The error that occurred.
+     */
+    void onProvisionError(Exception error);
+
+    /** Called by a session when it successfully completes a provisioning operation. */
+    void onProvisionCompleted();
+  }
+
+  /** Callback to be notified when the session is released. */
+  public interface ReleaseCallback<T extends ExoMediaCrypto> {
+
+    /**
+     * Called immediately after releasing session resources.
+     *
+     * @param session The session.
+     */
+    void onSessionReleased(DefaultDrmSession<T> session);
+  }
+
+  private static final String TAG = "DefaultDrmSession";
+
+  private static final int MSG_PROVISION = 0;
+  private static final int MSG_KEYS = 1;
+  private static final int MAX_LICENSE_DURATION_TO_RENEW_SECONDS = 60;
+
+  /** The DRM scheme datas, or null if this session uses offline keys. */
+  @Nullable public final List<SchemeData> schemeDatas;
+
+  private final ExoMediaDrm<T> mediaDrm;
+  private final ProvisioningManager<T> provisioningManager;
+  private final ReleaseCallback<T> releaseCallback;
+  private final @DefaultDrmSessionManager.Mode int mode;
+  private final boolean playClearSamplesWithoutKeys;
+  private final boolean isPlaceholderSession;
+  private final HashMap<String, String> keyRequestParameters;
+  private final EventDispatcher<DefaultDrmSessionEventListener> eventDispatcher;
+  private final LoadErrorHandlingPolicy loadErrorHandlingPolicy;
+
+  /* package */ final MediaDrmCallback callback;
+  /* package */ final UUID uuid;
+  /* package */ final ResponseHandler responseHandler;
+
+  private @DrmSession.State int state;
+  private int referenceCount;
+  @Nullable private HandlerThread requestHandlerThread;
+  @Nullable private RequestHandler requestHandler;
+  @Nullable private T mediaCrypto;
+  @Nullable private DrmSessionException lastException;
+  @Nullable private byte[] sessionId;
+  @MonotonicNonNull private byte[] offlineLicenseKeySetId;
+
+  @Nullable private KeyRequest currentKeyRequest;
+  @Nullable private ProvisionRequest currentProvisionRequest;
+
+  /**
+   * Instantiates a new DRM session.
+   *
+   * @param uuid The UUID of the drm scheme.
+   * @param mediaDrm The media DRM.
+   * @param provisioningManager The manager for provisioning.
+   * @param releaseCallback The {@link ReleaseCallback}.
+   * @param schemeDatas DRM scheme datas for this session, or null if an {@code
+   *     offlineLicenseKeySetId} is provided or if {@code isPlaceholderSession} is true.
+   * @param mode The DRM mode. Ignored if {@code isPlaceholderSession} is true.
+   * @param isPlaceholderSession Whether this session is not expected to acquire any keys.
+   * @param offlineLicenseKeySetId The offline license key set identifier, or null when not using
+   *     offline keys.
+   * @param keyRequestParameters Key request parameters.
+   * @param callback The media DRM callback.
+   * @param playbackLooper The playback looper.
+   * @param eventDispatcher The dispatcher for DRM session manager events.
+   * @param loadErrorHandlingPolicy The {@link LoadErrorHandlingPolicy} for key and provisioning
+   *     requests.
+   */
+  // the constructor does not initialize fields: sessionId
+  @SuppressWarnings("nullness:initialization.fields.uninitialized")
+  public DefaultDrmSession(
+      UUID uuid,
+      ExoMediaDrm<T> mediaDrm,
+      ProvisioningManager<T> provisioningManager,
+      ReleaseCallback<T> releaseCallback,
+      @Nullable List<SchemeData> schemeDatas,
+      @DefaultDrmSessionManager.Mode int mode,
+      boolean playClearSamplesWithoutKeys,
+      boolean isPlaceholderSession,
+      @Nullable byte[] offlineLicenseKeySetId,
+      HashMap<String, String> keyRequestParameters,
+      MediaDrmCallback callback,
+      Looper playbackLooper,
+      EventDispatcher<DefaultDrmSessionEventListener> eventDispatcher,
+      LoadErrorHandlingPolicy loadErrorHandlingPolicy) {
+    if (mode == DefaultDrmSessionManager.MODE_QUERY
+        || mode == DefaultDrmSessionManager.MODE_RELEASE) {
+      Assertions.checkNotNull(offlineLicenseKeySetId);
+    }
+    this.uuid = uuid;
+    this.provisioningManager = provisioningManager;
+    this.releaseCallback = releaseCallback;
+    this.mediaDrm = mediaDrm;
+    this.mode = mode;
+    this.playClearSamplesWithoutKeys = playClearSamplesWithoutKeys;
+    this.isPlaceholderSession = isPlaceholderSession;
+    if (offlineLicenseKeySetId != null) {
+      this.offlineLicenseKeySetId = offlineLicenseKeySetId;
+      this.schemeDatas = null;
+    } else {
+      this.schemeDatas = Collections.unmodifiableList(Assertions.checkNotNull(schemeDatas));
+    }
+    this.keyRequestParameters = keyRequestParameters;
+    this.callback = callback;
+    this.eventDispatcher = eventDispatcher;
+    this.loadErrorHandlingPolicy = loadErrorHandlingPolicy;
+    state = STATE_OPENING;
+    responseHandler = new ResponseHandler(playbackLooper);
+  }
+
+  public boolean hasSessionId(byte[] sessionId) {
+    return Arrays.equals(this.sessionId, sessionId);
+  }
+
+  public void onMediaDrmEvent(int what) {
+    switch (what) {
+      case ExoMediaDrm.EVENT_KEY_REQUIRED:
+        onKeysRequired();
+        break;
+      default:
+        break;
+    }
+  }
+
+  // Provisioning implementation.
+
+  public void provision() {
+    currentProvisionRequest = mediaDrm.getProvisionRequest();
+    Util.castNonNull(requestHandler)
+        .post(
+            MSG_PROVISION,
+            Assertions.checkNotNull(currentProvisionRequest),
+            /* allowRetry= */ true);
+  }
+
+  public void onProvisionCompleted() {
+    if (openInternal(false)) {
+      doLicense(true);
+    }
+  }
+
+  public void onProvisionError(Exception error) {
+    onError(error);
+  }
+
+  // DrmSession implementation.
+
+  @Override
+  @DrmSession.State
+  public final int getState() {
+    return state;
+  }
+
+  @Override
+  public boolean playClearSamplesWithoutKeys() {
+    return playClearSamplesWithoutKeys;
+  }
+
+  @Override
+  public final @Nullable DrmSessionException getError() {
+    return state == STATE_ERROR ? lastException : null;
+  }
+
+  @Override
+  public final @Nullable T getMediaCrypto() {
+    return mediaCrypto;
+  }
+
+  @Override
+  @Nullable
+  public Map<String, String> queryKeyStatus() {
+    return sessionId == null ? null : mediaDrm.queryKeyStatus(sessionId);
+  }
+
+  @Override
+  @Nullable
+  public byte[] getOfflineLicenseKeySetId() {
+    return offlineLicenseKeySetId;
+  }
+
+  @Override
+  public void acquire() {
+    Assertions.checkState(referenceCount >= 0);
+    if (++referenceCount == 1) {
+      Assertions.checkState(state == STATE_OPENING);
+      requestHandlerThread = new HandlerThread("DrmRequestHandler");
+      requestHandlerThread.start();
+      requestHandler = new RequestHandler(requestHandlerThread.getLooper());
+      if (openInternal(true)) {
+        doLicense(true);
+      }
+    }
+  }
+
+  @Override
+  public void release() {
+    if (--referenceCount == 0) {
+      // Assigning null to various non-null variables for clean-up.
+      state = STATE_RELEASED;
+      Util.castNonNull(responseHandler).removeCallbacksAndMessages(null);
+      Util.castNonNull(requestHandler).removeCallbacksAndMessages(null);
+      requestHandler = null;
+      Util.castNonNull(requestHandlerThread).quit();
+      requestHandlerThread = null;
+      mediaCrypto = null;
+      lastException = null;
+      currentKeyRequest = null;
+      currentProvisionRequest = null;
+      if (sessionId != null) {
+        mediaDrm.closeSession(sessionId);
+        sessionId = null;
+        eventDispatcher.dispatch(DefaultDrmSessionEventListener::onDrmSessionReleased);
+      }
+      releaseCallback.onSessionReleased(this);
+    }
+  }
+
+  // Internal methods.
+
+  /**
+   * Try to open a session, do provisioning if necessary.
+   *
+   * @param allowProvisioning if provisioning is allowed, set this to false when calling from
+   *     processing provision response.
+   * @return true on success, false otherwise.
+   */
+  @EnsuresNonNullIf(result = true, expression = "sessionId")
+  private boolean openInternal(boolean allowProvisioning) {
+    if (isOpen()) {
+      // Already opened
+      return true;
+    }
+
+    try {
+      sessionId = mediaDrm.openSession();
+      mediaCrypto = mediaDrm.createMediaCrypto(sessionId);
+      eventDispatcher.dispatch(DefaultDrmSessionEventListener::onDrmSessionAcquired);
+      state = STATE_OPENED;
+      Assertions.checkNotNull(sessionId);
+      return true;
+    } catch (NotProvisionedException e) {
+      if (allowProvisioning) {
+        provisioningManager.provisionRequired(this);
+      } else {
+        onError(e);
+      }
+    } catch (Exception e) {
+      onError(e);
+    }
+
+    return false;
+  }
+
+  private void onProvisionResponse(Object request, Object response) {
+    if (request != currentProvisionRequest || (state != STATE_OPENING && !isOpen())) {
+      // This event is stale.
+      return;
+    }
+    currentProvisionRequest = null;
+
+    if (response instanceof Exception) {
+      provisioningManager.onProvisionError((Exception) response);
+      return;
+    }
+
+    try {
+      mediaDrm.provideProvisionResponse((byte[]) response);
+    } catch (Exception e) {
+      provisioningManager.onProvisionError(e);
+      return;
+    }
+
+    provisioningManager.onProvisionCompleted();
+  }
+
+  @RequiresNonNull("sessionId")
+  private void doLicense(boolean allowRetry) {
+    if (isPlaceholderSession) {
+      return;
+    }
+    byte[] sessionId = Util.castNonNull(this.sessionId);
+    switch (mode) {
+      case DefaultDrmSessionManager.MODE_PLAYBACK:
+      case DefaultDrmSessionManager.MODE_QUERY:
+        if (offlineLicenseKeySetId == null) {
+          postKeyRequest(sessionId, ExoMediaDrm.KEY_TYPE_STREAMING, allowRetry);
+        } else if (state == STATE_OPENED_WITH_KEYS || restoreKeys()) {
+          long licenseDurationRemainingSec = getLicenseDurationRemainingSec();
+          if (mode == DefaultDrmSessionManager.MODE_PLAYBACK
+              && licenseDurationRemainingSec <= MAX_LICENSE_DURATION_TO_RENEW_SECONDS) {
+            Log.d(
+                TAG,
+                "Offline license has expired or will expire soon. "
+                    + "Remaining seconds: "
+                    + licenseDurationRemainingSec);
+            postKeyRequest(sessionId, ExoMediaDrm.KEY_TYPE_OFFLINE, allowRetry);
+          } else if (licenseDurationRemainingSec <= 0) {
+            onError(new KeysExpiredException());
+          } else {
+            state = STATE_OPENED_WITH_KEYS;
+            eventDispatcher.dispatch(DefaultDrmSessionEventListener::onDrmKeysRestored);
+          }
+        }
+        break;
+      case DefaultDrmSessionManager.MODE_DOWNLOAD:
+        if (offlineLicenseKeySetId == null || restoreKeys()) {
+          postKeyRequest(sessionId, ExoMediaDrm.KEY_TYPE_OFFLINE, allowRetry);
+        }
+        break;
+      case DefaultDrmSessionManager.MODE_RELEASE:
+        Assertions.checkNotNull(offlineLicenseKeySetId);
+        Assertions.checkNotNull(this.sessionId);
+        // It's not necessary to restore the key (and open a session to do that) before releasing it
+        // but this serves as a good sanity/fast-failure check.
+        if (restoreKeys()) {
+          postKeyRequest(offlineLicenseKeySetId, ExoMediaDrm.KEY_TYPE_RELEASE, allowRetry);
+        }
+        break;
+      default:
+        break;
+    }
+  }
+
+  @RequiresNonNull({"sessionId", "offlineLicenseKeySetId"})
+  private boolean restoreKeys() {
+    try {
+      mediaDrm.restoreKeys(sessionId, offlineLicenseKeySetId);
+      return true;
+    } catch (Exception e) {
+      Log.e(TAG, "Error trying to restore keys.", e);
+      onError(e);
+    }
+    return false;
+  }
+
+  private long getLicenseDurationRemainingSec() {
+    if (!C.WIDEVINE_UUID.equals(uuid)) {
+      return Long.MAX_VALUE;
+    }
+    Pair<Long, Long> pair =
+        Assertions.checkNotNull(WidevineUtil.getLicenseDurationRemainingSec(this));
+    return Math.min(pair.first, pair.second);
+  }
+
+  private void postKeyRequest(byte[] scope, int type, boolean allowRetry) {
+    try {
+      currentKeyRequest = mediaDrm.getKeyRequest(scope, schemeDatas, type, keyRequestParameters);
+      Util.castNonNull(requestHandler)
+          .post(MSG_KEYS, Assertions.checkNotNull(currentKeyRequest), allowRetry);
+    } catch (Exception e) {
+      onKeysError(e);
+    }
+  }
+
+  private void onKeyResponse(Object request, Object response) {
+    if (request != currentKeyRequest || !isOpen()) {
+      // This event is stale.
+      return;
+    }
+    currentKeyRequest = null;
+
+    if (response instanceof Exception) {
+      onKeysError((Exception) response);
+      return;
+    }
+
+    try {
+      byte[] responseData = (byte[]) response;
+      if (mode == DefaultDrmSessionManager.MODE_RELEASE) {
+        mediaDrm.provideKeyResponse(Util.castNonNull(offlineLicenseKeySetId), responseData);
+        eventDispatcher.dispatch(DefaultDrmSessionEventListener::onDrmKeysRestored);
+      } else {
+        byte[] keySetId = mediaDrm.provideKeyResponse(sessionId, responseData);
+        if ((mode == DefaultDrmSessionManager.MODE_DOWNLOAD
+                || (mode == DefaultDrmSessionManager.MODE_PLAYBACK
+                    && offlineLicenseKeySetId != null))
+            && keySetId != null
+            && keySetId.length != 0) {
+          offlineLicenseKeySetId = keySetId;
+        }
+        state = STATE_OPENED_WITH_KEYS;
+        eventDispatcher.dispatch(DefaultDrmSessionEventListener::onDrmKeysLoaded);
+      }
+    } catch (Exception e) {
+      onKeysError(e);
+    }
+  }
+
+  private void onKeysRequired() {
+    if (mode == DefaultDrmSessionManager.MODE_PLAYBACK && state == STATE_OPENED_WITH_KEYS) {
+      Util.castNonNull(sessionId);
+      doLicense(/* allowRetry= */ false);
+    }
+  }
+
+  private void onKeysError(Exception e) {
+    if (e instanceof NotProvisionedException) {
+      provisioningManager.provisionRequired(this);
+    } else {
+      onError(e);
+    }
+  }
+
+  private void onError(final Exception e) {
+    lastException = new DrmSessionException(e);
+    eventDispatcher.dispatch(listener -> listener.onDrmSessionManagerError(e));
+    if (state != STATE_OPENED_WITH_KEYS) {
+      state = STATE_ERROR;
+    }
+  }
+
+  @EnsuresNonNullIf(result = true, expression = "sessionId")
+  @SuppressWarnings("contracts.conditional.postcondition.not.satisfied")
+  private boolean isOpen() {
+    return state == STATE_OPENED || state == STATE_OPENED_WITH_KEYS;
+  }
+
+  // Internal classes.
+
+  @SuppressLint("HandlerLeak")
+  private class ResponseHandler extends Handler {
+
+    public ResponseHandler(Looper looper) {
+      super(looper);
+    }
+
+    @Override
+    @SuppressWarnings("unchecked")
+    public void handleMessage(Message msg) {
+      Pair<Object, Object> requestAndResponse = (Pair<Object, Object>) msg.obj;
+      Object request = requestAndResponse.first;
+      Object response = requestAndResponse.second;
+      switch (msg.what) {
+        case MSG_PROVISION:
+          onProvisionResponse(request, response);
+          break;
+        case MSG_KEYS:
+          onKeyResponse(request, response);
+          break;
+        default:
+          break;
+      }
+    }
+  }
+
+  @SuppressLint("HandlerLeak")
+  private class RequestHandler extends Handler {
+
+    public RequestHandler(Looper backgroundLooper) {
+      super(backgroundLooper);
+    }
+
+    void post(int what, Object request, boolean allowRetry) {
+      RequestTask requestTask =
+          new RequestTask(allowRetry, /* startTimeMs= */ SystemClock.elapsedRealtime(), request);
+      obtainMessage(what, requestTask).sendToTarget();
+    }
+
+    @Override
+    public void handleMessage(Message msg) {
+      RequestTask requestTask = (RequestTask) msg.obj;
+      Object response;
+      try {
+        switch (msg.what) {
+          case MSG_PROVISION:
+            response =
+                callback.executeProvisionRequest(uuid, (ProvisionRequest) requestTask.request);
+            break;
+          case MSG_KEYS:
+            response = callback.executeKeyRequest(uuid, (KeyRequest) requestTask.request);
+            break;
+          default:
+            throw new RuntimeException();
+        }
+      } catch (Exception e) {
+        if (maybeRetryRequest(msg, e)) {
+          return;
+        }
+        response = e;
+      }
+      responseHandler
+          .obtainMessage(msg.what, Pair.create(requestTask.request, response))
+          .sendToTarget();
+    }
+
+    private boolean maybeRetryRequest(Message originalMsg, Exception e) {
+      RequestTask requestTask = (RequestTask) originalMsg.obj;
+      if (!requestTask.allowRetry) {
+        return false;
+      }
+      requestTask.errorCount++;
+      if (requestTask.errorCount
+          > loadErrorHandlingPolicy.getMinimumLoadableRetryCount(C.DATA_TYPE_DRM)) {
+        return false;
+      }
+      IOException ioException =
+          e instanceof IOException ? (IOException) e : new UnexpectedDrmSessionException(e);
+      long retryDelayMs =
+          loadErrorHandlingPolicy.getRetryDelayMsFor(
+              C.DATA_TYPE_DRM,
+              /* loadDurationMs= */ SystemClock.elapsedRealtime() - requestTask.startTimeMs,
+              ioException,
+              requestTask.errorCount);
+      if (retryDelayMs == C.TIME_UNSET) {
+        // The error is fatal.
+        return false;
+      }
+      sendMessageDelayed(Message.obtain(originalMsg), retryDelayMs);
+      return true;
+    }
+  }
+
+  private static final class RequestTask {
+
+    public final boolean allowRetry;
+    public final long startTimeMs;
+    public final Object request;
+    public int errorCount;
+
+    public RequestTask(boolean allowRetry, long startTimeMs, Object request) {
+      this.allowRetry = allowRetry;
+      this.startTimeMs = startTimeMs;
+      this.request = request;
+    }
+  }
+}