[Chromecast] Allow CMA backend to notify of key expiry

This allows CMA backend implementations to notify us when
keys have expired.  We will need a corresponding internal
CL to handle this event in the CDM and send keystatuseschange
event upward to JS.

BUG=internal b/22702612

Review URL: https://codereview.chromium.org/1407253007

Cr-Commit-Position: refs/heads/master@{#360523}

chromecast/media/audio/cast_audio_output_stream.cc

@@ -175,6 +175,10 @@ class CastAudioOutputStream::Backend : public MediaPipelineBackend::Delegate {
       OnPushBufferComplete(decoder_, MediaPipelineBackend::kBufferFailed);
   }
 
+  void OnKeyStatusChanged(const std::string& key_id,
+                          CastKeyStatus key_status,
+                          uint32_t system_code) override {}
+
   base::WeakPtr<CastAudioOutputStream::Backend> GetWeakPtr() {
     return weak_factory_.GetWeakPtr();
   }

chromecast/media/cdm/browser_cdm_cast.cc

@@ -126,17 +126,25 @@ void BrowserCdmCast::OnSessionClosed(const std::string& session_id) {
   session_closed_cb_.Run(session_id);
 }
 
-void BrowserCdmCast::OnSessionKeysChange(
-    const std::string& session_id,
-    const ::media::KeyIdAndKeyPairs& keys) {
-  ::media::CdmKeysInfo cdm_keys_info;
+void BrowserCdmCast::OnSessionKeysChange(const std::string& session_id,
+                                         bool newly_usable_keys,
+                                         ::media::CdmKeysInfo keys_info) {
+  session_keys_change_cb_.Run(session_id, newly_usable_keys, keys_info.Pass());
+
+  if (newly_usable_keys)
+    player_tracker_impl_->NotifyNewKey();
+}
+
+void BrowserCdmCast::KeyIdAndKeyPairsToInfo(
+    const ::media::KeyIdAndKeyPairs& keys,
+    ::media::CdmKeysInfo* keys_info) {
+  DCHECK(keys_info);
   for (const std::pair<std::string, std::string>& key : keys) {
-    cdm_keys_info.push_back(new ::media::CdmKeyInformation(
-        key.first, ::media::CdmKeyInformation::USABLE, 0));
+    scoped_ptr<::media::CdmKeyInformation> cdm_key_information(
+        new ::media::CdmKeyInformation(key.first,
+                                       ::media::CdmKeyInformation::USABLE, 0));
+    keys_info->push_back(cdm_key_information.release());
   }
-  session_keys_change_cb_.Run(session_id, true, cdm_keys_info.Pass());
-
-  player_tracker_impl_->NotifyNewKey();
 }
 
 // A macro runs current member function on |task_runner_| thread.

chromecast/media/cdm/browser_cdm_cast.h

@@ -16,6 +16,7 @@
 #include "base/memory/ref_counted.h"
 #include "base/sequenced_task_runner_helpers.h"
 #include "base/threading/thread_checker.h"
+#include "chromecast/public/media/cast_key_status.h"
 #include "media/base/media_keys.h"
 #include "media/base/player_tracker.h"
 #include "media/cdm/json_web_key.h"
@@ -62,6 +63,12 @@ class BrowserCdmCast : public ::media::MediaKeys,
   virtual scoped_ptr<DecryptContextImpl> GetDecryptContext(
       const std::string& key_id) const = 0;
 
+  // Notifies that key status has changed (e.g. if expiry is detected by
+  // hardware decoder).
+  virtual void SetKeyStatus(const std::string& key_id,
+                            CastKeyStatus key_status,
+                            uint32_t system_code) = 0;
+
  protected:
   ~BrowserCdmCast() override;
 
@@ -71,7 +78,11 @@ class BrowserCdmCast : public ::media::MediaKeys,
                         ::media::MediaKeys::MessageType message_type);
   void OnSessionClosed(const std::string& session_id);
   void OnSessionKeysChange(const std::string& session_id,
-                           const ::media::KeyIdAndKeyPairs& keys);
+                           bool newly_usable_keys,
+                           ::media::CdmKeysInfo keys_info);
+
+  void KeyIdAndKeyPairsToInfo(const ::media::KeyIdAndKeyPairs& keys,
+                              ::media::CdmKeysInfo* key_info);
 
  private:
   friend class BrowserCdmCastUi;

chromecast/media/cma/backend/audio_video_pipeline_device_unittest.cc

@@ -99,6 +99,9 @@ class AudioVideoPipelineDeviceTest : public testing::Test,
                             MediaPipelineBackend::BufferStatus status) override;
   void OnEndOfStream(MediaPipelineBackend::Decoder* decoder) override;
   void OnDecoderError(MediaPipelineBackend::Decoder* decoder) override;
+  void OnKeyStatusChanged(const std::string& key_id,
+                          CastKeyStatus key_status,
+                          uint32_t system_code) override;
 
  private:
   void Initialize();
@@ -342,6 +345,12 @@ void AudioVideoPipelineDeviceTest::OnDecoderError(
   ASSERT_TRUE(false);
 }
 
+void AudioVideoPipelineDeviceTest::OnKeyStatusChanged(const std::string& key_id,
+                                                      CastKeyStatus key_status,
+                                                      uint32_t system_code) {
+  ASSERT_TRUE(false);
+}
+
 void AudioVideoPipelineDeviceTest::OnPushBufferComplete(
     MediaPipelineBackend::Decoder* decoder,
     MediaPipelineBackend::BufferStatus status) {

chromecast/media/cma/pipeline/media_pipeline_impl.cc

@@ -155,6 +155,15 @@ void MediaPipelineImpl::OnDecoderError(MediaPipelineBackend::Decoder* decoder) {
   }
 }
 
+void MediaPipelineImpl::OnKeyStatusChanged(const std::string& key_id,
+                                           CastKeyStatus key_status,
+                                           uint32_t system_code) {
+  CMALOG(kLogControl) << __FUNCTION__;
+  DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(cdm_);
+  cdm_->SetKeyStatus(key_id, key_status, system_code);
+}
+
 void MediaPipelineImpl::SetCdm(BrowserCdmCast* cdm) {
   CMALOG(kLogControl) << __FUNCTION__;
   DCHECK(thread_checker_.CalledOnValidThread());

chromecast/media/cma/pipeline/media_pipeline_impl.h

@@ -51,6 +51,9 @@ class MediaPipelineImpl : public MediaPipelineBackend::Delegate {
                             MediaPipelineBackend::BufferStatus status) override;
   void OnEndOfStream(MediaPipelineBackend::Decoder* decoder) override;
   void OnDecoderError(MediaPipelineBackend::Decoder* decoder) override;
+  void OnKeyStatusChanged(const std::string& key_id,
+                          CastKeyStatus key_status,
+                          uint32_t system_code) override;
 
   void InitializeAudio(const ::media::AudioDecoderConfig& config,
                        const AvPipelineClient& client,

chromecast/public/media/cast_key_status.h

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROMECAST_PUBLIC_MEDIA_CAST_KEY_STATUS_H_
+#define CHROMECAST_PUBLIC_MEDIA_CAST_KEY_STATUS_H_
+
+namespace chromecast {
+namespace media {
+
+// Status of encryption key.  See EME spec for details:
+// https://w3c.github.io/encrypted-media/  - not all key status values
+// are supported currently.
+enum CastKeyStatus { KEY_STATUS_USABLE = 0, KEY_STATUS_EXPIRED };
+
+}  // namespace media
+}  // namespace chromecast
+
+#endif  // CHROMECAST_PUBLIC_MEDIA_CAST_KEY_STATUS_H_

chromecast/public/media/media_pipeline_backend.h

@@ -5,6 +5,10 @@
 #ifndef CHROMECAST_PUBLIC_MEDIA_MEDIA_PIPELINE_BACKEND_H_
 #define CHROMECAST_PUBLIC_MEDIA_MEDIA_PIPELINE_BACKEND_H_
 
+#include <stdint.h>
+#include <string>
+
+#include "cast_key_status.h"
 #include "decoder_config.h"
 
 namespace chromecast {
@@ -142,6 +146,11 @@ class MediaPipelineBackend {
     // will be made after this is called.
     virtual void OnDecoderError(Decoder* decoder) = 0;
 
+    // Must be called when a decryption key status changes.
+    virtual void OnKeyStatusChanged(const std::string& key_id,
+                                    CastKeyStatus key_status,
+                                    uint32_t system_code) = 0;
+
    protected:
     virtual ~Delegate() {}
   };