Files
android/libwvdrmengine/cdm/core/include/crypto_session.h
Rahul Frias f6c2a60485 Allow Apps to Voluntarily Downgrade to L3 Crypto
This merges the following changes from the Widevine CDM repository:

564f4cc  Add CdmClientPropertySet to CDM
  Adds an interface to the CDM that allows it to query its client for
  certain properties.  In this case, this includes the ability to
  specify what security level is desired, as well as support for
  service ceritifcate privacy mode.

9cfbd3e  Force Level 3 fallback
  Adds support for voluntarily invoking L3 crypto to the OEMCrypto
  wrapper.

95d12c1  Add pointer to CdmClientPropertySet class to OpenSession.
  Adds support for storing the property set on a session-by-session
  basis and choosing the appropriate crypto level.

17de442  Add Settable Properties for Clank to Android
  Adds support for setting the aforementioned properties to the
  DrmEngine

bbe704d  Fixes to force fallback to level three security
  Corrections to invoke provisioning, OEMCrypto API with configured
  security level rather than the default. Unit tests were also revised.

Note that some parts of this are also support for the ability to use
a service certificate-based privacy mode. The remaining code for
supporting this mode is still forthcoming.

Bug: 10109249
Change-Id: I2755e4dea1de3e8a56cff237360298f7b7f1bddc
2013-08-15 11:31:45 -07:00

101 lines
3.4 KiB
C++

// Copyright 2012 Google Inc. All Rights Reserved.
//
// OEMCrypto Client - wrapper class for C-style OEMCrypto interface
//
#ifndef CDM_BASE_CRYPTO_SESSSION_H_
#define CDM_BASE_CRYPTO_SESSSION_H_
#include <string>
#include <map>
#include "lock.h"
#include "oemcrypto_adapter.h"
#include "OEMCryptoCENC.h"
#include "wv_cdm_types.h"
namespace wvcdm {
class CryptoKey;
typedef std::map<CryptoKeyId, CryptoKey*> CryptoKeyMap;
class CryptoSession {
public:
CryptoSession();
~CryptoSession();
bool ValidateKeybox();
bool GetToken(std::string* token);
CdmSecurityLevel GetSecurityLevel();
bool GetDeviceUniqueId(std::string* device_id);
bool GetSystemId(uint32_t* system_id);
bool GetProvisioningId(std::string* provisioning_id);
CdmResponseType Open() { return Open(kLevelDefault); }
CdmResponseType Open(SecurityLevel requested_security_level);
void Close();
bool IsOpen() { return open_; }
CryptoSessionId oec_session_id() { return oec_session_id_; }
// Key request/response
void GenerateRequestId(std::string& req_id_str);
bool PrepareRequest(const std::string& key_deriv_message,
bool is_provisioning, std::string* signature);
bool PrepareRenewalRequest(const std::string& message,
std::string* signature);
CdmResponseType LoadKeys(const std::string& message,
const std::string& signature,
const std::string& mac_key_iv,
const std::string& mac_key,
int num_keys, const CryptoKey* key_array);
bool LoadCertificatePrivateKey(std::string& wrapped_key);
bool RefreshKeys(const std::string& message, const std::string& signature,
int num_keys, const CryptoKey* key_array);
bool GenerateNonce(uint32_t* nonce);
bool GenerateDerivedKeys(const std::string& message);
bool GenerateDerivedKeys(const std::string& message,
const std::string& session_key);
bool RewrapDeviceRSAKey(const std::string& message,
const std::string& signature,
const std::string& nonce,
const std::string& enc_rsa_key,
const std::string& rsa_key_iv,
std::string* wrapped_rsa_key);
// Media data path
bool SelectKey(const std::string& key_id);
CdmResponseType Decrypt(const CdmDecryptionParameters& parameters);
bool GetRandom(size_t data_length, uint8_t* random_data);
private:
void Init();
void Terminate();
void GenerateMacContext(const std::string& input_context,
std::string* deriv_context);
void GenerateEncryptContext(const std::string& input_context,
std::string* deriv_context);
bool GenerateSignature(const std::string& message, bool use_rsa,
std::string* signature);
size_t GetOffset(std::string message, std::string field);
bool SetDestinationBufferType();
static const size_t kSignatureSize = 32; // size for HMAC-SHA256 signature
static Lock crypto_lock_;
static bool initialized_;
static int session_count_;
bool open_;
CryptoSessionId oec_session_id_;
OEMCryptoBufferType destination_buffer_type_;
bool is_destination_buffer_type_valid_;
SecurityLevel requested_security_level_;
CORE_DISALLOW_COPY_AND_ASSIGN(CryptoSession);
};
}; // namespace wvcdm
#endif // CDM_BASE_CRYPTO_SESSSION_H_