Cast: Added support for AES-CTR crypto.

media/cast/audio_receiver/audio_receiver.h

 // Copyright 2013 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 MEDIA_CAST_AUDIO_RECEIVER_AUDIO_RECEIVER_H_
 #define MEDIA_CAST_AUDIO_RECEIVER_AUDIO_RECEIVER_H_
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/threading/non_thread_safe.h"
 #include "base/time/tick_clock.h"
 #include "base/time/time.h"
+#include "crypto/encryptor.h"
 #include "media/cast/cast_config.h"
 #include "media/cast/cast_environment.h"
 #include "media/cast/cast_receiver.h"
 #include "media/cast/rtcp/rtcp.h"  // RtcpCastMessage
 #include "media/cast/rtp_common/rtp_defines.h"  // RtpCastHeader
 
 namespace media {
 namespace cast {
 
 class AudioDecoder;
@@ skipping 48 matching lines @@
 
   // Actual decoding implementation - should be called under the audio decoder
   // thread.
   void DecodeAudioFrameThread(int number_of_10ms_blocks,
                               int desired_frequency,
                               const AudioFrameDecodedCallback callback);
 
   // Return the playout time based on the current time and rtp timestamp.
   base::TimeTicks GetPlayoutTime(base::TimeTicks now, uint32 rtp_timestamp);
 
+  bool DecryptAudioFrame(const EncodedAudioFrame* encrypted_frame,

[Alpha Left Google, 2013/11/07 01:10:11]

Please add a comment about the parameters. Which one is input, which one is
output?

Why not just return scoped_ptr<EncodedAudioFrame> instead of using an output
pointer?

[pwestin, 2013/11/07 17:16:04]

it felt weird allowing the scoped ptr being empty and use that to check for
errors; just my preference  

+                         EncodedAudioFrame* audio_frame);
+
   // Schedule the next RTCP report.
   void ScheduleNextRtcpReport();
 
   // Actually send the next RTCP report.
   void SendNextRtcpReport();
 
   // Schedule timing for the next cast message.
   void ScheduleNextCastMessage();
 
   // Actually send the next cast message.
   void SendNextCastMessage();
 
   scoped_refptr<CastEnvironment> cast_environment_;
   base::WeakPtrFactory<AudioReceiver> weak_factory_;
 
   const AudioCodec codec_;
   const uint32 incoming_ssrc_;
   const int frequency_;
   base::TimeDelta target_delay_delta_;
   scoped_ptr<Framer> audio_buffer_;
   scoped_refptr<AudioDecoder> audio_decoder_;
   scoped_ptr<LocalRtpAudioData> incoming_payload_callback_;
   scoped_ptr<LocalRtpAudioFeedback> incoming_payload_feedback_;
   scoped_ptr<RtpReceiver> rtp_receiver_;
   scoped_ptr<Rtcp> rtcp_;
   scoped_ptr<RtpReceiverStatistics> rtp_audio_receiver_statistics_;
   base::TimeDelta time_offset_;
   base::TimeTicks time_first_incoming_packet_;
   uint32 first_incoming_rtp_timestamp_;
+  scoped_ptr<crypto::Encryptor> decryptor_;
+  std::string iv_mask_;
 
   std::list<AudioFrameEncodedCallback> queued_encoded_callbacks_;
 };
 
 }  // namespace cast
 }  // namespace media
 
 #endif  // MEDIA_CAST_AUDIO_RECEIVER_AUDIO_RECEIVER_H_