android/libwvdrmengine/cdm/include/wv_content_decryption_module.h

// Copyright 2013 Google Inc. All Rights Reserved.

#ifndef CDM_BASE_WV_CONTENT_DECRYPTION_MODULE_H_
#define CDM_BASE_WV_CONTENT_DECRYPTION_MODULE_H_

#include <map>

#include <UniquePtr.h>
#include <utils/RefBase.h>

#include "cdm_identifier.h"
#include "file_store.h"
#include "lock.h"
#include "metrics.pb.h"
#include "timer.h"
#include "wv_cdm_types.h"

namespace wvcdm {

class CdmClientPropertySet;
class CdmEngine;
class WvCdmEventListener;

class WvContentDecryptionModule : public android::RefBase, public TimerHandler {
 public:
  WvContentDecryptionModule();
  virtual ~WvContentDecryptionModule();

  // Static methods
  static bool IsSupported(const std::string& init_data_type);
  static bool IsCenc(const std::string& init_data_type);
  static bool IsWebm(const std::string& init_data_type);
  static bool IsHls(const std::string& init_data_type);

  // Session related methods
  virtual CdmResponseType OpenSession(const CdmKeySystem& key_system,
                                      CdmClientPropertySet* property_set,
                                      const CdmIdentifier& identifier,
                                      WvCdmEventListener* event_listener,
                                      CdmSessionId* session_id);
  virtual CdmResponseType CloseSession(const CdmSessionId& session_id);
  virtual bool IsOpenSession(const CdmSessionId& session_id);

  // Construct a valid license request.
  virtual CdmResponseType GenerateKeyRequest(const CdmSessionId& session_id,
                                             const CdmKeySetId& key_set_id,
                                             const std::string& init_data_type,
                                             const CdmInitData& init_data,
                                             const CdmLicenseType license_type,
                                             CdmAppParameterMap& app_parameters,
                                             CdmClientPropertySet* property_set,
                                             const CdmIdentifier& identifier,
                                             CdmKeyRequest* key_request);

  // Accept license response and extract key info.
  virtual CdmResponseType AddKey(const CdmSessionId& session_id,
                                 const CdmKeyResponse& key_data,
                                 CdmKeySetId* key_set_id);

  // Setup keys for offline usage which were retrived in an earlier key request
  virtual CdmResponseType RestoreKey(const CdmSessionId& session_id,
                                     const CdmKeySetId& key_set_id);

  // Cancel session
  virtual CdmResponseType RemoveKeys(const CdmSessionId& session_id);

  // Query system information
  virtual CdmResponseType QueryStatus(SecurityLevel security_level,
                                      const std::string& key,
                                      std::string* value);
  // Query session information
  virtual CdmResponseType QuerySessionStatus(const CdmSessionId& session_id,
                                             CdmQueryMap* key_info);

  // Query license information
  virtual CdmResponseType QueryKeyStatus(const CdmSessionId& session_id,
                                         CdmQueryMap* key_info);

  // Query OEMCrypto session ID
  virtual CdmResponseType QueryOemCryptoSessionId(const CdmSessionId& session_id,
                                                  CdmQueryMap* response);

  // Provisioning related methods
  virtual CdmResponseType GetProvisioningRequest(
      CdmCertificateType cert_type,
      const std::string& cert_authority,
      const CdmIdentifier& identifier,
      CdmProvisioningRequest* request,
      std::string* default_url);

  virtual CdmResponseType HandleProvisioningResponse(
      const CdmIdentifier& identifier,
      CdmProvisioningResponse& response,
      std::string* cert,
      std::string* wrapped_key);

  virtual CdmResponseType Unprovision(CdmSecurityLevel level,
                                      const CdmIdentifier& identifier);

  // Secure stop related methods
  virtual CdmResponseType GetUsageInfo(const std::string& app_id,
                                       const CdmIdentifier& identifier,
                                       CdmUsageInfo* usage_info);
  virtual CdmResponseType GetUsageInfo(const std::string& app_id,
                                       const CdmSecureStopId& ssid,
                                       const CdmIdentifier& identifier,
                                       CdmUsageInfo* usage_info);
  virtual CdmResponseType ReleaseAllUsageInfo(const std::string& app_id,
                                              const CdmIdentifier& identifier);
  virtual CdmResponseType ReleaseUsageInfo(
      const CdmUsageInfoReleaseMessage& message,
      const CdmIdentifier& identifier);

  // Accept encrypted buffer and decrypt data.
  // Decryption parameters that need to be specified are
  // is_encrypted, is_secure, key_id, encrypt_buffer, encrypt_length,
  // iv, block_offset, decrypt_buffer, decrypt_buffer_length,
  // decrypt_buffer_offset and subsample_flags
  virtual CdmResponseType Decrypt(const CdmSessionId& session_id,
                                  bool validate_key_id,
                                  const CdmDecryptionParameters& parameters);

  virtual void NotifyResolution(const CdmSessionId& session_id, uint32_t width,
                                uint32_t height);

  // Validate a passed-in service certificate
  virtual bool IsValidServiceCertificate(const std::string& certificate);

  // Retrieve the serialized metrics from CdmEngine and CdmSession instances
  // that have been closed.
  virtual void GetSerializedMetrics(std::string* serialized_metrics);

 private:
  struct CdmInfo {
    CdmInfo();

    FileSystem file_system;
    UniquePtr<CdmEngine> cdm_engine;
  };

  // Finds the CdmEngine instance for the given identifier, creating one if
  // needed.
  CdmEngine* EnsureCdmForIdentifier(const CdmIdentifier& identifier);
  // Finds the CdmEngine instance for the given session id, returning NULL if
  // not found.
  CdmEngine* GetCdmForSessionId(const std::string& session_id);
  // Closes CdmEngine instances that don't have any open sessions. Also stores
  // metrics data for closed CdmEngine instances.
  // Callers must acquire the cdms_lock_ before calling this method.
  void CloseCdmsWithoutSessions();

  uint32_t GenerateSessionSharingId();

  // timer related methods to drive policy decisions
  void EnablePolicyTimer();
  void DisablePolicyTimer();  // Disable if all cdm engines are closed.
  void ForceDisablePolicyTimer();  // Force disable the policy timer.
  void OnTimerEvent();

  static Lock session_sharing_id_generation_lock_;
  Lock policy_timer_lock_;
  Timer policy_timer_;

  // instance variables
  // This manages the lifetime of the CDM instances.
  std::map<CdmIdentifier, CdmInfo> cdms_;
  Lock cdms_lock_;

  // This contains weak pointers to the CDM instances contained in |cdms_|.
  std::map<std::string, CdmEngine*> cdm_by_session_id_;

  // The metrics for cdm engines and sessions that have been closed.
  drm_metrics::MetricsGroup metrics_;

  CORE_DISALLOW_COPY_AND_ASSIGN(WvContentDecryptionModule);
};

}  // namespace wvcdm

#endif  // CDM_BASE_WV_CONTENT_DECRYPTION_MODULE_H_