chromecast/media/base/decrypt_context.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROMECAST_MEDIA_BASE_DECRYPT_CONTEXT_H_
   6 #define CHROMECAST_MEDIA_BASE_DECRYPT_CONTEXT_H_
   7
   8 #include "base/macros.h"
   9 #include "base/memory/ref_counted.h"
  10 #include "chromecast/media/base/key_systems_common.h"
  11
  12 namespace crypto {
  13 class SymmetricKey;
  14 }
  15
  16 namespace chromecast {
  17 namespace media {
  18
  19 // Base class of a decryption context: a decryption context gathers all the
  20 // information needed to decrypt frames with a given key id.
  21 // Each CDM should implement this and add fields needed to fully describe a
  22 // decryption context.
  23 //
  24 class DecryptContext : public base::RefCountedThreadSafe<DecryptContext> {
  25  public:
  26   explicit DecryptContext(CastKeySystem key_system);
  27
  28   CastKeySystem key_system() const { return key_system_; }
  29
  30   // Returns the clear key if available, NULL otherwise.
  31   virtual crypto::SymmetricKey* GetKey() const;
  32
  33  protected:
  34   friend class base::RefCountedThreadSafe<DecryptContext>;
  35   virtual ~DecryptContext();
  36
  37  private:
  38   CastKeySystem key_system_;
  39
  40   DISALLOW_COPY_AND_ASSIGN(DecryptContext);
  41 };
  42
  43 }  // namespace media
  44 }  // namespace chromecast
  45
  46 #endif  // CHROMECAST_MEDIA_BASE_DECRYPT_CONTEXT_H_