/* * Copyright (C) 2013 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #ifndef DRM_API_H_ #define DRM_API_H_ #include #include #include #include #include #include // Loadable DrmEngine shared libraries should define the entry points // createDrmFactory and createCryptoFactory as shown below: // // extern "C" { // extern android::DrmFactory *createDrmFactory(); // extern android::CryptoFactory *createCryptoFactory(); // } namespace android { struct DrmPlugin; // DRMs are implemented in DrmEngine plugins, which are dynamically // loadable shared libraries that implement the entry points // createDrmFactory and createCryptoFactory. createDrmFactory // constructs and returns an instance of a DrmFactory object. Similarly, // createCryptoFactory creates an instance of a CryptoFactory object. // When a MediaCrypto or MediaDrm object needs to be constructed, all // available DrmEngines present in the plugins directory on the device // are scanned for a matching DrmEngine that can support the crypto // scheme. When a match is found, the DrmEngine's createCryptoPlugin and // createDrmPlugin methods are used to create CryptoPlugin or // DrmPlugin instances to support that DRM scheme. class DrmFactory { public: DrmFactory() {} virtual ~DrmFactory() {} // DrmFactory::isCryptoSchemeSupported can be called to determine // if the plugin factory is able to construct plugins that support a // given crypto scheme, which is specified by a UUID. virtual bool isCryptoSchemeSupported(const uint8_t uuid[16]) = 0; // Construct a DrmPlugin for the crypto scheme specified by UUID. virtual status_t createDrmPlugin( const uint8_t uuid[16], DrmPlugin **plugin) = 0; private: DrmFactory(const DrmFactory &); DrmFactory &operator=(const DrmFactory &); }; class DrmPlugin { public: enum EventType { kDrmPluginEventProvisionRequired, kDrmPluginEventKeyNeeded, kDrmPluginEventKeyExpired, kDrmPluginEventVendorDefined }; // Drm keys can be for offline content or for online streaming. // Offline keys are persisted on the device and may be used when the device // is disconnected from the network. enum KeyType { kKeyType_Offline, kKeyType_Streaming }; DrmPlugin() {} virtual ~DrmPlugin() {} // Open a new session with the DrmPlugin object. A session ID is returned // in the sessionId parameter. virtual status_t openSession(Vector &sessionId) = 0; // Close a session on the DrmPlugin object. virtual status_t closeSession(Vector const &sessionId) = 0; // A key request/response exchange occurs between the app and a License // Server to obtain the keys required to decrypt the content. getKeyRequest() // is used to obtain an opaque key request blob that is delivered to the // license server. // // The init data passed to getKeyRequest is container-specific and its // meaning is interpreted based on the mime type provided in the mimeType // parameter to getKeyRequest. It could contain, for example, the content // ID, key ID or other data obtained from the content metadata that is required // in generating the key request. // // keyType specifes if the keys are to be used for streaming or offline content // // optionalParameters are included in the key request message to allow a // client application to provide additional message parameters to the server. // // If successful, the opaque key request blob is returned to the caller. virtual status_t getKeyRequest(Vector const &sessionId, Vector const &initData, String8 const &mimeType, KeyType keyType, KeyedVector const &optionalParameters, Vector &request, String8 &defaultUrl) = 0; // After a key response is received by the app, it is provided to the // Drm plugin using provideKeyResponse. Returns the id of the key set // in keySetId. The keySetId can be used by removeKeys or restoreKeys // when the keys are used for offline content. virtual status_t provideKeyResponse(Vector const &sessionId, Vector const &response, Vector &keySetId) = 0; // Remove the persisted keys associated with an offline license for a session. virtual status_t removeKeys(Vector const &keySetId) = 0; // Restore persisted offline keys into a new session. keySetId identifies // the keys to load, obtained from a prior call to provideKeyResponse(). virtual status_t restoreKeys(Vector const &sessionId, Vector const &keySetId) = 0; // Request an informative description of the license for the session. The status // is in the form of {name, value} pairs. Since DRM license policies vary by // vendor, the specific status field names are determined by each DRM vendor. // Refer to your DRM provider documentation for definitions of the field names // for a particular DrmEngine. virtual status_t queryKeyStatus(Vector const &sessionId, KeyedVector &infoMap) const = 0; // A provision request/response exchange occurs between the app and a // provisioning server to retrieve a device certificate. getProvisionRequest // is used to obtain an opaque key request blob that is delivered to the // provisioning server. // // If successful, the opaque provision request blob is returned to the caller. virtual status_t getProvisionRequest(Vector &request, String8 &defaultUrl) = 0; // After a provision response is received by the app, it is provided to the // Drm plugin using provideProvisionResponse. virtual status_t provideProvisionResponse(Vector const &response) = 0; // A means of enforcing the contractual requirement for a concurrent stream // limit per subscriber across devices is provided via SecureStop. SecureStop // is a means of securely monitoring the lifetime of sessions. Since playback // on a device can be interrupted due to reboot, power failure, etc. a means // of persisting the lifetime information on the device is needed. // // A signed version of the sessionID is written to persistent storage on the // device when each MediaCrypto object is created. The sessionID is signed by // the device private key to prevent tampering. // // In the normal case, playback will be completed, the session destroyed and // the Secure Stops will be queried. The App queries secure stops and forwards // the secure stop message to the server which verifies the signature and // notifies the server side database that the session destruction has been // confirmed. The persisted record on the client is only removed after positive // confirmation that the server received the message using releaseSecureStops(). virtual status_t getSecureStops(List > &secureStops) = 0; virtual status_t releaseSecureStops(Vector const &ssRelease) = 0; // Read a property value given the device property string. There are a few forms // of property access methods, depending on the data type returned. // Since DRM plugin properties may vary, additional field names may be defined // by each DRM vendor. Refer to your DRM provider documentation for definitions // of its additional field names. // // Standard values are: // "vendor" [string] identifies the maker of the plugin // "version" [string] identifies the version of the plugin // "description" [string] describes the plugin // 'deviceUniqueId' [byte array] The device unique identifier is established // during device provisioning and provides a means of uniquely identifying // each device. virtual status_t getPropertyString(String8 const &name, String8 &value ) const = 0; virtual status_t getPropertyByteArray(String8 const &name, Vector &value ) const = 0; // Write a property value given the device property string. There are a few forms // of property setting methods, depending on the data type. // Since DRM plugin properties may vary, additional field names may be defined // by each DRM vendor. Refer to your DRM provider documentation for definitions // of its field names. virtual status_t setPropertyString(String8 const &name, String8 const &value ) = 0; virtual status_t setPropertyByteArray(String8 const &name, Vector const &value ) = 0; // The following methods implement operations on a CryptoSession to support // encrypt, decrypt, sign verify operations on operator-provided // session keys. // // The algorithm string conforms to JCA Standard Names for Cipher // Transforms and is case insensitive. For example "AES/CBC/PKCS5Padding". // // Return OK if the algorithm is supported, otherwise return BAD_VALUE // virtual status_t setCipherAlgorithm(Vector const &sessionId, String8 const &algorithm) = 0; // // The algorithm string conforms to JCA Standard Names for Mac // Algorithms and is case insensitive. For example "HmacSHA256". // // Return OK if the algorithm is supported, otherwise return BAD_VALUE // virtual status_t setMacAlgorithm(Vector const &sessionId, String8 const &algorithm) = 0; // Encrypt the provided input buffer with the cipher algorithm // specified by setCipherAlgorithm and the key selected by keyId, // and return the encrypted data. virtual status_t encrypt(Vector const &sessionId, Vector const &keyId, Vector const &input, Vector const &iv, Vector &output) = 0; // Decrypt the provided input buffer with the cipher algorithm // specified by setCipherAlgorithm and the key selected by keyId, // and return the decrypted data. virtual status_t decrypt(Vector const &sessionId, Vector const &keyId, Vector const &input, Vector const &iv, Vector &output) = 0; // Compute a signature on the provided message using the mac algorithm // specified by setMacAlgorithm and the key selected by keyId, // and return the signature. virtual status_t sign(Vector const &sessionId, Vector const &keyId, Vector const &message, Vector &signature) = 0; // Compute a signature on the provided message using the mac algorithm // specified by setMacAlgorithm and the key selected by keyId, // and compare with the expected result. Set result to true or // false depending on the outcome. virtual status_t verify(Vector const &sessionId, Vector const &keyId, Vector const &message, Vector const &signature, bool &match) = 0; // TODO: provide way to send an event private: DISALLOW_EVIL_CONSTRUCTORS(DrmPlugin); }; } // namespace android #endif // DRM_API_H_