// Copyright 2013 Google Inc. All Rights Reserved. /********************************************************************* * OEMCryptoCENC.h * * Reference APIs needed to support Widevine's crypto algorithms. * * See the document "WV Modular DRM Security Integration Guide for Common * Encryption (CENC) -- version 12" for a description of this API. You * can find this document in the widevine repository as * docs/WidevineModularDRMSecurityIntegrationGuideforCENC.pdf * Changes between different versions of this API are documented in the files * docs/Widevine_Modular_DRM_Version_*_Delta.pdf * *********************************************************************/ #ifndef OEMCRYPTO_CENC_H_ #define OEMCRYPTO_CENC_H_ #include #include #include #ifdef __cplusplus extern "C" { #endif typedef uint32_t OEMCrypto_SESSION; typedef enum OEMCryptoResult { OEMCrypto_SUCCESS = 0, OEMCrypto_ERROR_INIT_FAILED = 1, OEMCrypto_ERROR_TERMINATE_FAILED = 2, OEMCrypto_ERROR_OPEN_FAILURE = 3, OEMCrypto_ERROR_CLOSE_FAILURE = 4, OEMCrypto_ERROR_ENTER_SECURE_PLAYBACK_FAILED = 5, OEMCrypto_ERROR_EXIT_SECURE_PLAYBACK_FAILED = 6, OEMCrypto_ERROR_SHORT_BUFFER = 7, OEMCrypto_ERROR_NO_DEVICE_KEY = 8, OEMCrypto_ERROR_NO_ASSET_KEY = 9, OEMCrypto_ERROR_KEYBOX_INVALID = 10, OEMCrypto_ERROR_NO_KEYDATA = 11, OEMCrypto_ERROR_NO_CW = 12, OEMCrypto_ERROR_DECRYPT_FAILED = 13, OEMCrypto_ERROR_WRITE_KEYBOX = 14, OEMCrypto_ERROR_WRAP_KEYBOX = 15, OEMCrypto_ERROR_BAD_MAGIC = 16, OEMCrypto_ERROR_BAD_CRC = 17, OEMCrypto_ERROR_NO_DEVICEID = 18, OEMCrypto_ERROR_RNG_FAILED = 19, OEMCrypto_ERROR_RNG_NOT_SUPPORTED = 20, OEMCrypto_ERROR_SETUP = 21, OEMCrypto_ERROR_OPEN_SESSION_FAILED = 22, OEMCrypto_ERROR_CLOSE_SESSION_FAILED = 23, OEMCrypto_ERROR_INVALID_SESSION = 24, OEMCrypto_ERROR_NOT_IMPLEMENTED = 25, OEMCrypto_ERROR_NO_CONTENT_KEY = 26, OEMCrypto_ERROR_CONTROL_INVALID = 27, OEMCrypto_ERROR_UNKNOWN_FAILURE = 28, OEMCrypto_ERROR_INVALID_CONTEXT = 29, OEMCrypto_ERROR_SIGNATURE_FAILURE = 30, OEMCrypto_ERROR_TOO_MANY_SESSIONS = 31, OEMCrypto_ERROR_INVALID_NONCE = 32, OEMCrypto_ERROR_TOO_MANY_KEYS = 33, OEMCrypto_ERROR_DEVICE_NOT_RSA_PROVISIONED = 34, OEMCrypto_ERROR_INVALID_RSA_KEY = 35, OEMCrypto_ERROR_KEY_EXPIRED = 36, OEMCrypto_ERROR_INSUFFICIENT_RESOURCES = 37, OEMCrypto_ERROR_INSUFFICIENT_HDCP = 38, OEMCrypto_ERROR_BUFFER_TOO_LARGE = 39, } OEMCryptoResult; /* * OEMCrypto_DestBufferDesc * Describes the type and access information for the memory to receive * decrypted data. * * The OEMCrypto API supports a range of client device architectures. * Different architectures have different methods for acquiring and securing * buffers that will hold portions of the audio or video stream after * decryption. Three basic strategies are recognized for handling decrypted * stream data: * 1. Return the decrypted data in the clear into normal user memory * (ClearBuffer). The caller uses normal memory allocation methods to * acquire a buffer, and supplies the memory address of the buffer in the * descriptor. * 2. Place the decrypted data into protected memory (SecureBuffer). The * caller uses a platform-specific method to acquire the protected buffer * and a user-memory handle that references it. The handle is supplied * to the decrypt call in the descriptor. * 3. Place the decrypted data directly into the audio or video decoder fifo * (Direct). The caller will use platform-specific methods to initialize * the fifo and the decoders. The decrypted stream data is not accessible * to the caller. * * Specific fields are as follows: * * (type == OEMCrypto_BufferType_Clear) * address - Address of start of user memory buffer. * max_length - Size of user memory buffer. * (type == OEMCrypto_BufferType_Secure) * buffer - handle to a platform-specific secure buffer. * max_length - Size of platform-specific secure buffer. * (type == OEMCrypto_BufferType_Direct) * is_video - If true, decrypted bytes are routed to the video * decoder. If false, decrypted bytes are routed to the * audio decoder. */ typedef enum OEMCryptoBufferType { OEMCrypto_BufferType_Clear, OEMCrypto_BufferType_Secure, OEMCrypto_BufferType_Direct } OEMCryptoBufferType; typedef struct { OEMCryptoBufferType type; union { struct { // type == OEMCrypto_BufferType_Clear uint8_t* address; size_t max_length; } clear; struct { // type == OEMCrypto_BufferType_Secure void* handle; size_t max_length; size_t offset; } secure; struct { // type == OEMCrypto_BufferType_Direct bool is_video; } direct; } buffer; } OEMCrypto_DestBufferDesc; /** OEMCryptoCipherMode is used in LoadKeys to prepare a key for either CTR * decryption or CBC decryption. */ typedef enum OEMCryptoCipherMode { OEMCrypto_CipherMode_CTR, OEMCrypto_CipherMode_CBC, } OEMCryptoCipherMode; /* * OEMCrypto_KeyObject * Points to the relevant fields for a content key. The fields are extracted * from the License Response message offered to OEMCrypto_LoadKeys(). Each * field points to one of the components of the key. Key data, key control, * and both IV fields are 128 bits (16 bytes): * key_id - the unique id of this key. * key_id_length - the size of key_id. OEMCrypto may assume this is at * most 16. However, OEMCrypto shall correctly handle key id lengths * from 1 to 16 bytes. * key_data_iv - the IV for performing AES-128-CBC decryption of the * key_data field. * key_data - the key data. It is encrypted (AES-128-CBC) with the * session's derived encrypt key and the key_data_iv. * key_control_iv - the IV for performing AES-128-CBC decryption of the * key_control field. * key_control - the key control block. It is encrypted (AES-128-CBC) with * the content key from the key_data field. * cipher_mode - whether the key should be prepared for CTR mode or CBC mode * when used in later calls to DecryptCENC. * * The memory for the OEMCrypto_KeyObject fields is allocated and freed * by the caller of OEMCrypto_LoadKeys(). */ typedef struct { const uint8_t* key_id; size_t key_id_length; const uint8_t* key_data_iv; const uint8_t* key_data; size_t key_data_length; const uint8_t* key_control_iv; const uint8_t* key_control; OEMCryptoCipherMode cipher_mode; } OEMCrypto_KeyObject; /* * OEMCrypto_KeyRefreshObject * Points to the relevant fields for renewing a content key. The fields are * extracted from the License Renewal Response message offered to * OEMCrypto_RefreshKeys(). Each field points to one of the components of * the key. * key_id - the unique id of this key. * key_control_iv - the IV for performing AES-128-CBC decryption of the * key_control field. 16 bytes. * key_control - the key control block. It is encrypted (AES-128-CBC) with * the content key from the key_data field. 16 bytes. * * The key_data is unchanged from the original OEMCrypto_LoadKeys() call. Some * Key Control Block fields, especially those related to key lifetime, may * change. * * The memory for the OEMCrypto_KeyRefreshObject fields is allocated and freed * by the caller of OEMCrypto_RefreshKeys(). */ typedef struct { const uint8_t* key_id; size_t key_id_length; const uint8_t* key_control_iv; const uint8_t* key_control; } OEMCrypto_KeyRefreshObject; /* * OEMCrypto_Algorithm * This is a list of valid algorithms for OEMCrypto_Generic_* functions. * Some are valid for encryption/decryption, and some for signing/verifying. */ typedef enum OEMCrypto_Algorithm { OEMCrypto_AES_CBC_128_NO_PADDING = 0, OEMCrypto_HMAC_SHA256 = 1, } OEMCrypto_Algorithm; /* * Flags indicating data endpoints in OEMCrypto_DecryptCENC. */ #define OEMCrypto_FirstSubsample 1 #define OEMCrypto_LastSubsample 2 /* OEMCrypto_CENCEncryptPatternDesc * This is used in OEMCrypto_DecryptCENC to indicate the encrypt/skip pattern * used, as specified in the CENC standard. */ typedef struct { size_t encrypt; // number of 16 byte blocks to decrypt. size_t skip; // number of 16 byte blocks to leave in clear. size_t offset; // offset into the pattern in blocks for this call. } OEMCrypto_CENCEncryptPatternDesc; /* * OEMCrypto_Usage_Entry_Status. * Valid values for status in the usage table. */ typedef enum OEMCrypto_Usage_Entry_Status { kUnused = 0, kActive = 1, kInactive = 2 } OEMCrypto_Usage_Entry_Status; /* * OEMCrypto_PST_Report is used to report an entry from the Usage Table. */ typedef struct { uint8_t signature[20]; // -- HMAC SHA1 of the rest of the report. uint8_t status; // current status of entry. (OEMCrypto_Usage_Entry_Status) uint8_t clock_security_level; uint8_t pst_length; uint8_t padding; // make int64's word aligned. int64_t seconds_since_license_received; // now - time_of_license_received int64_t seconds_since_first_decrypt; // now - time_of_first_decrypt int64_t seconds_since_last_decrypt; // now - time_of_last_decrypt uint8_t pst[]; } __attribute__((packed)) OEMCrypto_PST_Report; /* * OEMCrypto_Clock_Security_Level. * Valid values for clock_security_level in OEMCrypto_PST_Report. */ typedef enum OEMCrypto_Clock_Security_Level { kInsecureClock = 0, kSecureTimer = 1, kSecureClock = 2, kHardwareSecureClock = 3 } OEMCrypto_Clock_Security_Level; typedef enum RSA_Padding_Scheme { kSign_RSASSA_PSS = 0x1, // RSASSA-PSS with SHA1. kSign_PKCS1_Block1 = 0x2, // PKCS1 with block type 1 padding (only). } RSA_Padding_Scheme; /* * OEMCrypto_HDCP_Capability is used in the key control block to enforce HDCP * level, and in GetHDCPCapability for reporting. */ typedef enum OEMCrypto_HDCP_Capability { HDCP_NONE = 0, // No HDCP supported, no secure data path. HDCP_V1 = 1, // HDCP version 1.0 HDCP_V2 = 2, // HDCP version 2.0 HDCP_V2_1 = 3, // HDCP version 2.1 HDCP_V2_2 = 4, // HDCP version 2.2 Type 1. HDCP_NO_DIGITAL_OUTPUT = 0xff // No digital output. } OEMCrypto_HDCP_Capability; /* Return value for OEMCrypto_GetProvisioningMethod(). */ typedef enum OEMCrypto_ProvisioningMethod { OEMCrypto_ProvisioningError = 0, // Device cannot be provisioned. OEMCrypto_DrmCertificate = 1, // Device has baked in DRM certificate // (level 3 only) OEMCrypto_Keybox = 2, // Device has factory installed unique keybox. OEMCrypto_OEMCertificate = 3 // Device has factory installed OEM certificate. } OEMCrypto_ProvisioningMethod; /* * Obfuscation Renames. */ #define OEMCrypto_Initialize _oecc01 #define OEMCrypto_Terminate _oecc02 #define OEMCrypto_InstallKeybox _oecc03 #define OEMCrypto_GetKeyData _oecc04 #define OEMCrypto_IsKeyboxValid _oecc05 #define OEMCrypto_GetRandom _oecc06 #define OEMCrypto_GetDeviceID _oecc07 #define OEMCrypto_WrapKeybox _oecc08 #define OEMCrypto_OpenSession _oecc09 #define OEMCrypto_CloseSession _oecc10 #define OEMCrypto_DecryptCTR_V10 _oecc11 #define OEMCrypto_GenerateDerivedKeys _oecc12 #define OEMCrypto_GenerateSignature _oecc13 #define OEMCrypto_GenerateNonce _oecc14 #define OEMCrypto_LoadKeys_V8 _oecc15 #define OEMCrypto_RefreshKeys _oecc16 #define OEMCrypto_SelectKey _oecc17 #define OEMCrypto_RewrapDeviceRSAKey _oecc18 #define OEMCrypto_LoadDeviceRSAKey _oecc19 #define OEMCrypto_GenerateRSASignature_V8 _oecc20 #define OEMCrypto_DeriveKeysFromSessionKey _oecc21 #define OEMCrypto_APIVersion _oecc22 #define OEMCrypto_SecurityLevel _oecc23 #define OEMCrypto_Generic_Encrypt _oecc24 #define OEMCrypto_Generic_Decrypt _oecc25 #define OEMCrypto_Generic_Sign _oecc26 #define OEMCrypto_Generic_Verify _oecc27 #define OEMCrypto_GetHDCPCapability_V9 _oecc28 #define OEMCrypto_SupportsUsageTable _oecc29 #define OEMCrypto_UpdateUsageTable _oecc30 #define OEMCrypto_DeactivateUsageEntry _oecc31 #define OEMCrypto_ReportUsage _oecc32 #define OEMCrypto_DeleteUsageEntry _oecc33 #define OEMCrypto_DeleteUsageTable _oecc34 #define OEMCrypto_LoadKeys_V9_or_V10 _oecc35 #define OEMCrypto_GenerateRSASignature _oecc36 #define OEMCrypto_GetMaxNumberOfSessions _oecc37 #define OEMCrypto_GetNumberOfOpenSessions _oecc38 #define OEMCrypto_IsAntiRollbackHwPresent _oecc39 #define OEMCrypto_CopyBuffer _oecc40 #define OEMCrypto_QueryKeyControl _oecc41 #define OEMCrypto_LoadTestKeybox _oecc42 #define OEMCrypto_ForceDeleteUsageEntry _oecc43 #define OEMCrypto_GetHDCPCapability _oecc44 #define OEMCrypto_LoadTestRSAKey _oecc45 #define OEMCrypto_Security_Patch_Level _oecc46 #define OEMCrypto_LoadKeys _oecc47 #define OEMCrypto_DecryptCENC _oecc48 #define OEMCrypto_GetProvisioningMethod _oecc49 #define OEMCrypto_GetOEMPublicCertificate _oecc50 #define OEMCrypto_RewrapDeviceRSAKey30 _oecc51 /* * OEMCrypto_Initialize * * Description: * Initialize the crypto firmware/hardware. * * Parameters: * N/A * * Threading: * No other function calls will be made while this function is running. This * function will not be called again before OEMCrypto_Terminate. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_INIT_FAILED failed to initialize crypto hardware * * Version: * This method is supported by all API versions. */ OEMCryptoResult OEMCrypto_Initialize(void); /* * OEMCrypto_Terminate * * Description: * Closes the crypto operation and releases all related resources. * * Parameters: * N/A * * Threading: * No other OEMCrypto calls are made while this function is running. After * this function is called, no other OEMCrypto calls will be made until * another call to OEMCrypto_Initialize is made. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_TERMINATE_FAILED failed to de-initialize crypto hardware * * Version: * This method is supported by all API versions. */ OEMCryptoResult OEMCrypto_Terminate(void); /* * OEMCrypto_OpenSession * * Description: * Open a new crypto security engine context. The security engine hardware and * firmware shall acquire resources that are needed to support the session, * and return a session handle that identifies that session in future calls. * * Parameters: * session (out) - an opaque handle that the crypto firmware uses to identify * the session. * * Threading: * No other Open/Close session calls will be made while this function is * running. Functions on other existing sessions may be called while this * function is active. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_TOO_MANY_SESSIONS failed because too many sessions are open * OEMCrypto_ERROR_OPEN_SESSION_FAILED failed to initialize the crypto session * * Version: * This method changed in API version 5. */ OEMCryptoResult OEMCrypto_OpenSession(OEMCrypto_SESSION* session); /* * OEMCrypto_CloseSession * * Description: * Closes the crypto security engine session and frees any associated * resources. * * Parameters: * session (in) - handle for the session to be closed. * * Threading: * No other Open/Close session calls will be made while this function is * running. Functions on other existing sessions may be called while this * function is active. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_INVALID_SESSION no open session with that id. * OEMCrypto_ERROR_CLOSE_SESSION_FAILED failed to terminate the crypto session * * Version: * This method changed in API version 5. */ OEMCryptoResult OEMCrypto_CloseSession(OEMCrypto_SESSION session); /* * OEMCrypto_GenerateDerivedKeys * * Description: * Generates three secondary keys -- mac_key_server, mac_key_client, and * encrypt_key -- for handling signing and content key decryption under the * license server protocol for AES CTR mode. * * Refer to document "Widevine Modular DRM Security Integration Guide for * CENC" for details. This function computes the AES-128-CMAC of the * enc_key_context and stores it in secure memory as the encrypt_key. It * then computes four cycles of AES-128-CMAC of the mac_key_context and * stores it in the mac_keys. The first two cycles are used for * mac_key_server and the second two cycles are used for mac_key_client. * These three keys will be stored until the next call to LoadKeys. * * Parameters: * session (in) - handle for the session to be used. * mac_key_context (in) - pointer to memory containing context data for * computing the HMAC generation key. * mac_key_context_length (in) - length of the HMAC key context data, in * bytes. * enc_key_context (in) - pointer to memory containing context data for * computing the encryption key. * enc_key_context_length (in) - length of the encryption key context data, in * bytes. * * * Results: * mac_key_server: the 256 bit mac key is generated and stored in secure * memory. * mac_key_client: the 256 bit mac key is generated and stored in secure * memory. * enc_key: the 128 bit encryption key is generated and stored in secure * memory. * * Threading: * This function may be called simultaneously with functions on other * sessions, but not with other functions on this session. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_NO_DEVICE_KEY * OEMCrypto_ERROR_INVALID_SESSION * OEMCrypto_ERROR_INVALID_CONTEXT * OEMCrypto_ERROR_INSUFFICIENT_RESOURCES * OEMCrypto_ERROR_UNKNOWN_FAILURE * OEMCrypto_ERROR_BUFFER_TOO_LARGE * * Buffer Sizes * OEMCrypto shall support message sizes of at least 8 KiB. * OEMCrypto shall return OEMCrypto_ERROR_BUFFER_TOO_LARGE if the buffer is * larger than the supported size. * * Version: * This method changed in API version 8. */ OEMCryptoResult OEMCrypto_GenerateDerivedKeys(OEMCrypto_SESSION session, const uint8_t* mac_key_context, uint32_t mac_key_context_length, const uint8_t* enc_key_context, uint32_t enc_key_context_length); /* * OEMCrypto_GenerateNonce * * Description: * Generates a 32-bit nonce to detect possible replay attack on the key * control block. The nonce is stored in secure memory and will be used * for the next call to LoadKeys. * * Because the nonce will be used to prevent replay attacks, it is desirable * that a rogue application cannot rapidly call this function until a * repeated nonce is created randomly. With this in mind, if more than 20 * nonces are requested within one second, OEMCrypto will return an error * after the 20th and not generate any more nonces for the rest of the * second. After an error, if the application waits at least one second * before requesting more nonces, then OEMCrypto will reset the error * condition and generate valid nonces again. * * Parameters: * session (in) - crypto session identifier. * nonce (out) - pointer to memory to received the computed nonce. * * Results: * nonce: the nonce is also stored in secure memory. At least 4 nonces should * be stored for each session. * * Threading: * This function may be called simultaneously with functions on other * sessions, but not with other functions on this session. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_INVALID_SESSION * OEMCrypto_ERROR_INSUFFICIENT_RESOURCES * OEMCrypto_ERROR_UNKNOWN_FAILURE * * Version: * This method changed in API version 5. */ OEMCryptoResult OEMCrypto_GenerateNonce(OEMCrypto_SESSION session, uint32_t* nonce); /* * OEMCrypto_GenerateSignature * * Description: * Generates a HMAC-SHA256 signature for license request signing under the * license server protocol for AES CTR mode. This uses the key mac_key_client. * * NOTE: OEMCrypto_GenerateDerivedKeys() must be called first to establish the * mac_key_client. * * Refer to document "Widevine Modular DRM Security Integration Guide for * CENC" for details. * * NOTE: if signature pointer is null and/or input signature_length set to * zero, this function returns OEMCrypto_ERROR_SHORT_BUFFER and sets output * signature_length to the size needed to receive the output signature. * * Parameters: * session (in) - crypto session identifier. * message (in) - pointer to memory containing message to be signed. * message_length (in) - length of the message, in bytes. * signature (out) - pointer to memory to received the computed signature. May * be null (see note above). * signature_length (in/out) - (in) length of the signature buffer, in bytes. * (out) actual length of the signature, in bytes. * * Threading: * This function may be called simultaneously with functions on other * sessions, but not with other functions on this session. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_INVALID_SESSION * OEMCrypto_ERROR_SHORT_BUFFER if signature buffer is not large enough to * hold the buffer. * OEMCrypto_ERROR_INSUFFICIENT_RESOURCES * OEMCrypto_ERROR_UNKNOWN_FAILURE * OEMCrypto_ERROR_BUFFER_TOO_LARGE * * Buffer Sizes * OEMCrypto shall support message sizes of at least 8 KiB. * OEMCrypto shall return OEMCrypto_ERROR_BUFFER_TOO_LARGE if the buffer is * larger than the supported size. * * Version: * This method changed in API version 5. */ OEMCryptoResult OEMCrypto_GenerateSignature(OEMCrypto_SESSION session, const uint8_t* message, size_t message_length, uint8_t* signature, size_t* signature_length); /* * OEMCrypto_LoadKeys * * Description: * Installs a set of keys for performing decryption in the current session. * * The relevant fields have been extracted from the License Response protocol * message, but the entire message and associated signature are provided so * the message can be verified (using HMAC-SHA256 with the derived * mac_key_server). If the signature verification fails, ignore all other * arguments and return OEMCrypto_ERROR_SIGNATURE_FAILURE. Otherwise, add the * keys to the session context. * * The keys will be decrypted using the current encrypt_key (AES-128-CBC) and * the IV given in the KeyObject. Each key control block will be decrypted * using the first 128 bits of the corresponding content key (AES-128-CBC) and * the IV given in the KeyObject. * * If it is not null, enc_mac_keys will be used to create new mac_keys. After * all keys have been decrypted and validated, the new mac_keys are decrypted * with the current encrypt_key and the offered IV. The new mac_keys replaces * the current mac_keys for future calls to OEMCrypto_RefreshKeys(). The first * 256 bits of the mac_keys become the mac_key[server] and the following 256 * bits of the mac_keys become the mac_key[client]. If enc_mac_keys is null, * then there will not be a call to OEMCrypto_RefreshKeys for this session and * the current mac_keys should remain unchanged. * * The mac_key and encrypt_key were generated and stored by the previous call * to OEMCrypto_GenerateDerivedKeys(). The nonce was generated and stored by * the previous call to OEMCrypto_GenerateNonce(). * * This session’s elapsed time clock is started at 0. The clock will be used * in OEMCrypto_DecryptCENC(). * * NOTE: The calling software must have previously established the mac_keys * and encrypt_key with a call to OEMCrypto_GenerateDerivedKeys(), * OEMCrypto_DeriveKeysFromSessionKey(), or a previous call to * OEMCrypto_LoadKeys(). * * Refer to document "Widevine Modular DRM Security Integration Guide for * CENC" for details. * * OEMCrypto shall handle at least 20 keys per session. This allows a * single license to contain separate keys for 3 key rotations (previous * interval, current interval, next interval) times 4 content keys (audio, * SD, HD, UHD) plus up to 8 keys for watermarks. * * Verification: * The following checks should be performed. If any check fails, an error is * returned, and none of the keys are loaded. * * 1. The signature of the message shall be computed, and the API shall * verify the computed signature matches the signature passed in. If not, * return OEMCrypto_ERROR_SIGNATURE_FAILURE. The signature verification shall * use a constant-time algorithm (a signature mismatch will always take the * same time as a successful comparison). * * 2. The enc_mac_keys pointer must be either null, or point inside the * message. If the pointer enc_mac_keys is not null, the API shall verify * that the two pointers enc_mac_keys_iv and enc_mac_keys point to locations * in the message. I.e. (message <= p && p < message+message_length)for p in * each of enc_mac_keys_iv, enc_mac_keys. If not, return * OEMCrypto_ERROR_INVALID_CONTEXT. * * 3. The API shall verify that each pointer in each KeyObject points to a * location in the message. I.e. (message <= p && p < message+message_length) * for p in each of key_id, key_data_iv, key_data, key_control_iv, * key_control. If not, return OEMCrypto_ERROR_INVALID_CONTEXT. * * 4. Each key’s control block, after decryption, shall have a valid * verification field. If not, return OEMCrypto_ERROR_INVALID_CONTEXT. * * 5. If any key control block has the Nonce_Enabled bit set, that key’s Nonce * field shall match the nonce generated by the current nonce. If not, return * OEMCrypto_ERROR_INVALID_NONCE. If there is a match, remove that nonce from * the cache. Note that all the key control blocks in a particular call shall * have the same nonce value. * * 6. If any key control block has the Require_AntiRollback_Hardware bit set, * and the device does not protect the usage table from rollback, then do not * load the keys and return OEMCrypto_ERROR_UNKNOWN_FAILURE. * * 7. If the key control block has a nonzero Replay_Control, then the * verification described below is also performed. * * 8. If num_keys == 0, then return OEMCrypto_ERROR_INVALID_CONTEXT. * * Usage Table and Provider Session Token (pst): * * If a key control block has a nonzero value for Replay_Control, then all * keys in this license will have the same value. In this case, the following * additional checks are performed. * * The pointer pst must not be null, and must point to a location in the * message. If not, return OEMCrypto_ERROR_INVALID_CONTEXT. * * - If Replay_Control is 1 = Nonce_Required, then OEMCrypto will perform a * nonce check as described above. OEMCrypto will verify that the table * does not already have an entry for the value of pst passed in as a * parameter. If an entry already exists, an error * OEMCrypto_ERROR_INVALID_CONTEXT is returned and no keys are * loaded. OEMCrypto will then create a new entry in the table, and mark * this session as using this new entry. This prevents the license from * being loaded more than once, and will be used for online streaming. * * - If Replay_Control is 2 = "Require existing Session Usage table entry or * Nonce", then OEMCrypto will check the Session Usage table for an existing * entry with the same pst. * * --- If the pst is not in the table yet, a new entry will be created in the * table and this session shall use the new entry. In that case, the nonce * will be verified for each key. * * --- If an existing usage table entry is found, then this session will use * that entry. In that case, the nonce will not be verified for each key. * Also, the entry’s mac keys will be verified against the current * session’s mac keys. This allows an offline license to be reloaded but * maintain continuity of the playback times from one session to the next. * * - If the nonce is not valid and an existing entry is not found, the return * error is OEMCrypto_ERROR_INVALID_NONCE. * * Note: If LoadKeys updates the mac keys, then the new updated mac keys will * be used in the Usage Table. If LoadKeys does not update the mac keys, the * existing session mac keys are stored in the usage table. * * Sessions that are associated with an entry will need to be able to update * and verify the status of the entry, and the time stamps in the entry. * * Devices that do not support the Usage Table will return * OEMCrypto_ERROR_INVALID_CONTEXT if the Replay_Control is nonzero. * * Note: If LoadKeys creates a new entry in the usage table, OEMCrypto will * increment the Usage Table’s generation number, and then sign, encrypt, and * save the Usage Table. * * Parameters: * session (in) - crypto session identifier. * message (in) - pointer to memory containing message to be verified. * message_length (in) - length of the message, in bytes. * signature (in) - pointer to memory containing the signature. * signature_length (in) - length of the signature, in bytes. * enc_mac_keys_iv (in) - IV for decrypting new mac_key. Size is 128 bits. * enc_mac_keys (in) - encrypted mac_keys for generating new mac_keys. Size is * 512 bits. * num_keys (in) - number of keys present. * key_array (in) - set of keys to be installed. * pst (in) - the Provider Session Token. * pst_length (in) - the length of pst. * * Threading: * This function may be called simultaneously with functions on other * sessions, but not with other functions on this session. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_NO_DEVICE_KEY * OEMCrypto_ERROR_INVALID_SESSION * OEMCrypto_ERROR_INVALID_CONTEXT * OEMCrypto_ERROR_SIGNATURE_FAILURE * OEMCrypto_ERROR_INVALID_NONCE * OEMCrypto_ERROR_TOO_MANY_KEYS * OEMCrypto_ERROR_UNKNOWN_FAILURE * OEMCrypto_ERROR_BUFFER_TOO_LARGE * * Buffer Sizes * OEMCrypto shall support message sizes of at least 8 KiB. * OEMCrypto shall return OEMCrypto_ERROR_BUFFER_TOO_LARGE if the buffer is * larger than the supported size. * * Version: * This method changed in API version 11. */ OEMCryptoResult OEMCrypto_LoadKeys( OEMCrypto_SESSION session, const uint8_t* message, size_t message_length, const uint8_t* signature, size_t signature_length, const uint8_t* enc_mac_keys_iv, const uint8_t* enc_mac_keys, size_t num_keys, const OEMCrypto_KeyObject* key_array, const uint8_t* pst, size_t pst_length); /* * OEMCrypto_RefreshKeys * * Description: * Updates an existing set of keys for continuing decryption in the * current session. * * The relevant fields have been extracted from the Renewal Response protocol * message, but the entire message and associated signature are provided so * the message can be verified (using HMAC-SHA256 with the current * mac_key[server]). If any verification step fails, an error is returned. * Otherwise, the key table in trusted memory is updated using the * key_control block. When updating an entry in the table, only the duration, * nonce, and nonce_enabled fields are used. All other key control bits are * not modified. * * NOTE: OEMCrypto_GenerateDerivedKeys() or OEMCrypto_LoadKeys() must be * called first to establish the mac_key[server]. * * This session’s elapsed time clock is reset to 0 when this function is * called. The elapsed time clock is used in OEMCrypto_DecryptCENC(). * * This function does not add keys to the key table. It is only used to * update a key control block license duration. Refer to the License Signing * and Verification section above for more details. This function is used to * update the duration of a key, only. It is not used to update key control * bits. * * If the KeyRefreshObject’s key_control_iv is null, then the key_control is * not encrypted. If the key_control_iv is specified, then key_control is * encrypted with the first 128 bits of the corresponding content key. * * If the KeyRefreshObject’s key_id is null, then this refresh object should * be used to update the duration of all keys for the current session. In * this case, key_control_iv will also be null and the control block will not * be encrypted. * * * Verification: * The following checks should be performed. If any check fails, an error is * returned, and none of the keys are loaded. * * 1. The signature of the message shall be computed, and the API shall * verify the computed signature matches the signature passed in. If not, * return OEMCrypto_ERROR_SIGNATURE_FAILURE. The signature verification shall * use a constant-time algorithm (a signature mismatch will always take the * same time as a successful comparison). * * 2. The API shall verify that each pointer in each KeyObject points to a * location in the message, or is null. I.e. (message <= p && p < * message+message_length) for p in each of key_id,key_control_iv, * key_control. If not, return OEMCrypto_ERROR_INVALID_CONTEXT. * * 3. Each key’s control block shall have a valid verification field. If not, * return OEMCrypto_ERROR_INVALID_CONTEXT. * * 4. If the key control block has the Nonce_Enabled bit set, the Nonce field * shall match one of the nonces in the cache. If not, return * OEMCrypto_ERROR_INVALID_NONCE. If there is a match, remove that nonce from * the cache. Note that all the key control blocks in a particular call shall * have the same nonce value. * * Parameters: * session (in) - crypto session identifier. * message (in) - pointer to memory containing message to be verified. * message_length (in) - length of the message, in bytes. * signature (in) - pointer to memory containing the signature. * signature_length (in) - length of the signature, in bytes. * num_keys (in) - number of keys present. * key_array (in) - set of key updates. * * Threading: * This function may be called simultaneously with functions on other * sessions, but not with other functions on this session. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_NO_DEVICE_KEY * OEMCrypto_ERROR_INVALID_SESSION * OEMCrypto_ERROR_INVALID_CONTEXT * OEMCrypto_ERROR_INVALID_NONCE * OEMCrypto_ERROR_SIGNATURE_FAILURE * OEMCrypto_ERROR_INSUFFICIENT_RESOURCES * OEMCrypto_ERROR_UNKNOWN_FAILURE * OEMCrypto_ERROR_BUFFER_TOO_LARGE * * Buffer Sizes * OEMCrypto shall support message sizes of at least 8 KiB. * OEMCrypto shall return OEMCrypto_ERROR_BUFFER_TOO_LARGE if the buffer is * larger than the supported size. * * Version: * This method changed in API version 8. */ OEMCryptoResult OEMCrypto_RefreshKeys( OEMCrypto_SESSION session, const uint8_t* message, size_t message_length, const uint8_t* signature, size_t signature_length, size_t num_keys, const OEMCrypto_KeyRefreshObject* key_array); /* * OEMCrypto_QueryKeyControl * * Description: * Returns the decrypted key control block for the given key_id. This function * is for application developers to debug license server and key timelines. * It only returns a key control block if LoadKeys was successful, otherwise * it returns OEMCrypto_ERROR_NO_CONTENT_KEY. The developer of the OEMCrypto * library must be careful that the keys themselves are not accidentally * revealed. * * Note: * Returns control block in original, network byte order. If OEMCrypto * converts fields to host byte order internally for storage, it should * convert them back. Since OEMCrypto might not store the nonce or validation * fields, values of 0 may be used instead. * * Verification * The following checks should be performed. * 1) If key_id is null, return OEMCrypto_ERROR_INVALID_CONTEXT. * 2) If key_control_block_length is null, return * OEMCrypto_ERROR_INVALID_CONTEXT. * 3) If *key_control_block_length is less than the length of a key control * block, set it to the correct value, and return * OEMCrypto_ERROR_SHORT_BUFFER. * 4) If key_control_block is null, return OEMCrypto_ERROR_INVALID_CONTEXT. * 5) If the specified key has not been loaded, return * OEMCrypto_ERROR_NO_CONTENT_KEY. * * Parameters * key_id (in) - The unique id of the key of interest. * key_id_length (in) - The length of key_id, in bytes. From 1 to 16 * inclusive. * key_control_block(out) - A caller-owned buffer. * key_control_block_length (in/out) - The length of key_control_block buffer. * * Returns * OEMCrypto_SUCCESS * OEMCrypto_ERROR_INVALID_CONTEXT * OEMCrypto_ERROR_SHORT_BUFFER * OEMCrypto_ERROR_NO_CONTENT_KEY * OEMCrypto_ERROR_UNKNOWN_FAILURE * OEMCrypto_ERROR_BUFFER_TOO_LARGE * * Buffer Sizes * OEMCrypto shall support message sizes of at least 8 KiB. * OEMCrypto shall return OEMCrypto_ERROR_BUFFER_TOO_LARGE if the buffer is * larger than the supported size. * * Threading * This function may be called simultaneously with functions on other * sessions, but not with other functions on this session. * * Version * This method is added in API version 10. */ OEMCryptoResult OEMCrypto_QueryKeyControl(OEMCrypto_SESSION session, const uint8_t* key_id, size_t key_id_length, uint8_t* key_control_block, size_t* key_control_block_length); /* * OEMCrypto_SelectKey * * Description: * Select a content key and install it in the hardware key ladder for * subsequent decryption operations (OEMCrypto_DecryptCENC()) for this * session. The specified key must have been previously "installed" via * OEMCrypto_LoadKeys() or OEMCrypto_RefreshKeys(). * * A key control block is associated with the key and the session, and is used * to configure the session context. The Key Control data is documented in * "Key Control Block Definition". * * Step 1: Lookup the content key data via the offered key_id. The key data * includes the key value, and the key control block. * * Step 2: Latch the content key into the hardware key ladder. Set * permission flags and timers based on the key's control block. * * Step 3: use the latched content key to decrypt (AES-128-CTR) buffers * passed in via OEMCrypto_DecryptCENC(). If the key is 256 bits it * will be used for OEMCrypto_Generic_Sign or * OEMCrypto_Generic_Verify as specified in the key control * block. Continue to use this key until OEMCrypto_SelectKey() is * called again, or until OEMCrypto_CloseSession() is called. * * Verification: * The following checks should be performed if is_encrypted is true. If any * check fails, an error is returned, and no decryption is performed. * * 1. If the current key’s control block has a nonzero duration field, then * the API shall verify that the duration is greater than the session’s * elapsed time clock. If not, return OEMCrypto_ERROR_KEY_EXPIRED. * * * Parameters: * session (in) - crypto session identifier * key_id (in) - pointer to the Key ID * key_id_length (in) - length of the Key ID in bytes. From 1 to 16 * inclusive. * * Threading: * This function may be called simultaneously with functions on other * sessions, but not with other functions on this session. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_INVALID_SESSION crypto session ID invalid or not open * OEMCrypto_ERROR_NO_DEVICE_KEY failed to decrypt device key * OEMCrypto_ERROR_NO_CONTENT_KEY failed to decrypt content key * OEMCrypto_ERROR_CONTROL_INVALID invalid or unsupported control input * OEMCrypto_ERROR_KEYBOX_INVALID cannot decrypt and read from Keybox * OEMCrypto_ERROR_KEY_EXPIRED * OEMCrypto_ERROR_INSUFFICIENT_RESOURCES * OEMCrypto_ERROR_UNKNOWN_FAILURE * * Version: * This method changed in API version 8. */ OEMCryptoResult OEMCrypto_SelectKey(OEMCrypto_SESSION session, const uint8_t* key_id, size_t key_id_length); /* * OEMCrypto_DecryptCENC * * Description: * Decrypts or copies the payload in the buffer referenced by the *data_addr * parameter into the buffer referenced by the out_buffer parameter, using * the session context indicated by the session parameter. Decryption mode * is AES-128-CTR or AES-128-CBC depending on the value of cipher_mode set in * the OEMCrypto_KeyObject passed in to OEMCrypto_LoadKeys. If is_encrypted * is true, the content key associated with the session is latched in the * active hardware key ladder and is used for the decryption operation. If * is_encrypted is false, the data is simply copied. * * After decryption, the data_length bytes are copied to the location * described by out_buffer. This could be one of * * 1. The structure out_buffer contains a pointer to a clear text buffer. The * OEMCrypto library shall verify that key control allows data to be returned * in clear text. If it is not authorized, this method should return an * error. * * 2. The structure out_buffer contains a handle to a secure buffer. * * 3. The structure out_buffer indicates that the data should be sent * directly to the decoder and rendered. * * NOTES: * For CTR mode, IV points to the counter value to be used for the initial * encrypted block of the input buffer. The IV length is the AES block * size. For subsequent encrypted AES blocks the IV is calculated by * incrementing the lower 64 bits (byte 8-15) of the IV value used for the * previous block. The counter rolls over to zero when it reaches its maximum * value (0xFFFFFFFFFFFFFFFF). The upper 64 bits (byte 0-7) of the IV do not * change. * * For CBC mode, IV points to the initialization vector for cipher block * chaining. Within each subsample, OEMCrypto is responsible for updating * the IV as prescribed by CBC mode. The calling layer above is responsible * for updating the IV from one subsample to the next if needed. * * This method may be called several times before the decrypted data is used. * For this reason, the parameter subsample_flags may be used to optimize * decryption. The first buffer in a chunk of data will have the * OEMCrypto_FirstSubsample bit set in subsample_flags. The last buffer in a * chunk of data will have the OEMCrypto_LastSubsample bit set in * subsample_flags. The decrypted data will not be used until after * OEMCrypto_LastSubsample has been set. If an implementation decrypts data * immediately, it may ignore subsample_flags. * * If the destination buffer is secure, an offset may be specified. * DecryptCENC begins storing data out_buffer->secure.offset bytes after the * beginning of the secure buffer. * * If the session has an entry in the Usage Table, then OEMCrypto will update * the time_of_last_decrypt. If the status of the entry is "unused", then * change the status to "active" and set the time_of_first_decrypt. * * The decryption mode, either OEMCrypto_CipherMode_CTR or * OEMCrypto_CipherMode_CBC, was specified in the call to OEMCrypto_LoadKeys. * The encryption pattern is specified by the fields in the parameter * pattern. A description of partial encryption patterns can be found in the * document Draft International Standard ISO/IEC DIS 23001-7. Search for the * codes "cenc", "cbc1", "cens" or "cbcs". * * The most common mode is "cenc", which is OEMCrypto_CipherMode_CTR without * a pattern. The entire subsample is either encrypted or clear, depending * on the flag is_encrypted. In the structure pattern, both encrypt and skip * will be 0. This is the only mode that allows for a nonzero block_offset. * * A less common mode is "cens", which is OEMCrypto_CipherMode_CTR with an * encryption pattern. For this mode, OEMCrypto may assume that an encrypted * subsample will have a length that is a multiple of 16, the AES block * length. * * The mode "cbc1" is OEMCrypto_CipherMode_CBC without a pattern. In the * structure pattern, both encrypt and skip will be 0. If an encrypted * subsample has a length that is not a multiple of 16, the final partial * block will be in the clear. * * The mode "cbcs" is OEMCrypto_CipherMode_CBC with an encryption pattern. * This mode allows devices to decrypt HLS content. If an encrypted * subsample has a length that is not a multiple of 16, the final partial * block will be in the clear. * * Verification: * The following checks should be performed if is_encrypted is true. If any * check fails, an error is returned, and no decryption is performed. * * 1. If the current key’s control block has a nonzero Duration field, then * the API shall verify that the duration is greater than the session’s * elapsed time clock. If not, return OEMCrypto_ERROR_KEY_EXPIRED. * * 2. If the current key’s control block has the Data_Path_Type bit set, then * the API shall verify that the output buffer is secure or direct. If not, * return OEMCrypto_ERROR_DECRYPT_FAILED. * * 3. If the current key’s control block has the HDCP bit set, then the API * shall verify that the buffer will be output using HDCP only. If not, * return OEMCrypto_ERROR_DECRYPT_FAILED. * * 4. If the current key’s control block has a nonzero value for * HDCP_Version, then the current version of HDCP for the device and the * display combined will be compared against the version specified in the * control block. If the current version is not at least as high as that in * the control block, then return OEMCrypto_ERROR_INSUFFICIENT_HDCP. * * 5. If the current session has an entry in the Usage Table, and the status * of that entry is "inactive", then return OEMCrypto_ERROR_INVALID_SESSION. * * If the flag is_encrypted is false, then no verification is performed. This * call shall copy clear data even when there are no keys loaded, or there is * no selected key. * * Parameters: * session (in) - crypto session identifier. * data_addr (in) - An unaligned pointer to this segment of the stream. * data_length (in) - The length of this segment of the stream, in bytes. * is_encrypted (in) - True if the buffer described by data_addr, data_length * is encrypted. If is_encrypted is false, only the * data_addr and data_length parameters are used. The iv * and offset arguments are ignored. * iv (in) - The initial value block to be used for content decryption. * block_offset (in) - If non-zero, the decryption block boundary is * different from the start of the data. block_offset * should be subtracted from data_addr to compute the * starting address of the first decrypted block. The * bytes between the decryption block start address and * data_addr are discarded after decryption. It does not * adjust the beginning of the source or destination * data. This parameter satisfies 0 <= block_offset < * 16. This paramater is only used for CTR mode. * out_buffer (in) - A caller-owned descriptor that specifies the handling of * the decrypted byte stream. See OEMCrypto_DestbufferDesc * for details. * pattern (in) - A caller-owned structure indicating the encrypt/skip * pattern as specified in the CENC standard. * subsample_flags (in) - bitwise flags indicating if this is the first, * middle, or last subsample in a chunk of data. * 0 = neither first nor last subsample, * 1 = first subsample, * 2 = last subsample, * 3 = both first and last subsample. * * Threading: * This function may be called simultaneously with functions on other * sessions, but not with other functions on this session. * * Returns: * OEMCrypto_SUCCESS * OEMCrypto_ERROR_NO_DEVICE_KEY * OEMCrypto_ERROR_INVALID_SESSION * OEMCrypto_ERROR_INVALID_CONTEXT * OEMCrypto_ERROR_DECRYPT_FAILED * OEMCrypto_ERROR_KEY_EXPIRED * OEMCrypto_ERROR_INSUFFICIENT_HDCP * OEMCrypto_ERROR_INSUFFICIENT_RESOURCES * OEMCrypto_ERROR_UNKNOWN_FAILURE * OEMCrypto_ERROR_BUFFER_TOO_LARGE * * Buffer Sizes * OEMCrypto shall support subsample sizes (i.e. data_length) of at least * 100 KiB. * OEMCrypto shall return OEMCrypto_ERROR_BUFFER_TOO_LARGE if the buffer is * larger than the supported size. If OEMCrypto returns * OEMCrypto_ERROR_BUFFER_TOO_LARGE, the calling function must break the buffer * into smaller chunks. For high performance devices, OEMCrypto should handle * larger buffers. * * Version: * This method changed in API version 11. * This method changed its name in API version 11. */ OEMCryptoResult OEMCrypto_DecryptCENC( OEMCrypto_SESSION session, const uint8_t* data_addr, size_t data_length, bool is_encrypted, const uint8_t* iv, size_t block_offset, OEMCrypto_DestBufferDesc* out_buffer, const OEMCrypto_CENCEncryptPatternDesc* pattern, uint8_t subsample_flags); /* * OEMCrypto_CopyBuffer * * Description: * Copies the payload in the buffer referenced by the *data_addr parameter * into the buffer referenced by the out_buffer parameter. The data is simply * copied. The definition of OEMCrypto_DestBufferDesc and subsample_flags are * the same as in OEMCrypto_DecryptCENC, above. * * The main difference between this and DecryptCENC is that this function * does not need an open session, and it may be called concurrently with * other session functions on a multithreaded system. In particular, an * application will use this to copy the clear leader of a video to a secure * buffer while the license request is being generated, sent to the server, * and the response is being processed. This functionality is needed because * an application may not have read or write access to a secure destination * buffer. * * NOTES: * * This method may be called several times before the data is used. The * first buffer in a chunk of data will have the OEMCrypto_FirstSubsample bit * set in subsample_flags. The last buffer in a chunk of data will have the * OEMCrypto_LastSubsample bit set in subsample_flags. The data will not be * used until after OEMCrypto_LastSubsample has been set. If an * implementation copies data immediately, it may ignore subsample_flags. * * If the destination buffer is secure, an offset may be specified. * CopyBuffer begins storing data out_buffer->secure.offset bytes after the * beginning of the secure buffer. * * Verification * The following checks should be performed. * 1. If either data_addr or out_buffer is null, return * OEMCrypto_ERROR_INVALID_CONTEXT. * * Parameters * data_addr (in) - An unaligned pointer to the buffer to be copied. * data_length (in) - The length of the buffer, in bytes. * out_buffer (out) - A caller-owned descriptor that specifies the handling * of the byte stream. See OEMCrypto_DestbufferDesc for * details. * subsample_flags (in) - bitwise flags indicating if this is the first, * middle, or last subsample in a chunk of data. * 0 = neither first nor last subsample, * 1 = first subsample, * 2 = last subsample, * 3 = both first and last subsample. * * Returns * OEMCrypto_SUCCESS * OEMCrypto_ERROR_INVALID_CONTEXT * OEMCrypto_ERROR_UNKNOWN_FAILURE * OEMCrypto_ERROR_BUFFER_TOO_LARGE * * Buffer Sizes * OEMCrypto shall support subsample sizes (i.e. data_length) of at least * 100 KiB. * OEMCrypto shall return OEMCrypto_ERROR_BUFFER_TOO_LARGE if the buffer is * larger than the supported size. If OEMCrypto returns * OEMCrypto_ERROR_BUFFER_TOO_LARGE, the calling function must break the buffer * into smaller chunks. For high performance devices, OEMCrypto should handle * larger buffers. * * Threading * This function may be called simultaneously with any other functions. * Version * This method is added in API version 10. */ OEMCryptoResult OEMCrypto_CopyBuffer(const uint8_t* data_addr, size_t data_length, OEMCrypto_DestBufferDesc* out_buffer, uint8_t subsample_flags); /* * OEMCrypto_WrapKeybox * * Description: * During manufacturing, the keybox should be encrypted with the OEM root key * and stored on the file system in a region that will not be erased during * factory reset. As described in section 5.5.4, the keybox may be directly * encrypted and stored on the device in a single step, or it may use the * two-step WrapKeybox/InstallKeybox approach. When the Widevine DRM plugin * initializes, it will look for a wrapped keybox in the file * /factory/wv.keys and install it into the security processor by calling * OEMCrypto_InstallKeybox(). * * OEMCrypto_WrapKeybox() is used to generate an OEM-encrypted keybox that * may be passed to OEMCrypto_InstallKeybox() for provisioning. The keybox * may be either passed in the clear or previously encrypted with a transport * key. If a transport key is supplied, the keybox is first decrypted with * the transport key before being wrapped with the OEM root key. This * function is only needed if the provisioning method involves saving the * keybox to the file system. * * Parameters: * keybox (in) - pointer to Keybox data to encrypt. May be NULL on the first * call to test size of wrapped keybox. The keybox may either be clear or * previously encrypted. * keyboxLength (in) - length the keybox data in bytes * wrappedKeybox (out) – Pointer to wrapped keybox * wrappedKeyboxLength (out) – Pointer to the length of the wrapped keybox in * bytes * transportKey (in) – Optional. AES transport key. If provided, the keybox * parameter was previously encrypted with this key. The keybox will be * decrypted with the transport key using AES-CBC and a null IV. * transportKeyLength (in) – Optional. Number of bytes in the transportKey, if * used. * * Threading: * This function is not called simultaneously with any other functions * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_WRAP_KEYBOX failed to wrap Keybox * OEMCrypto_ERROR_SHORT_BUFFER if keybox is provided as NULL, to determine * the size of the wrapped keybox * OEMCrypto_ERROR_INSUFFICIENT_RESOURCES * OEMCrypto_ERROR_NOT_IMPLEMENTED * * Version: * This method is supported by all API versions. */ OEMCryptoResult OEMCrypto_WrapKeybox(const uint8_t* keybox, size_t keyBoxLength, uint8_t* wrappedKeybox, size_t* wrappedKeyBoxLength, const uint8_t* transportKey, size_t transportKeyLength); /* * OEMCrypto_InstallKeybox * * Description: * Decrypts a wrapped keybox and installs it in the security processor. The * keybox is unwrapped then encrypted with the OEM root key. This function is * called from the Widevine DRM plugin at initialization time if there is no * valid keybox installed. It looks for a wrapped keybox in the file * /factory/wv.keys and if it is present, will read the file and call * OEMCrypto_InstallKeybox() with the contents of the file. * * Parameters: * keybox (in) - pointer to encrypted Keybox data as input * keyboxLength (in) - length of the keybox data in bytes * * Threading: * This function is not called simultaneously with any other functions. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_BAD_MAGIC * OEMCrypto_ERROR_BAD_CRC * OEMCrypto_ERROR_INSUFFICIENT_RESOURCES * OEMCrypto_ERROR_WRITE_KEYBOX failed to handle and store Keybox * * Version: * This method is supported in all API versions. */ OEMCryptoResult OEMCrypto_InstallKeybox(const uint8_t* keybox, size_t keyBoxLength); /* * OEMCrypto_GetProvisioningMethod * * Description: * This function is for OEMCrypto to tell the layer above what provisioning * method it uses: keybox or OEM certificate. * * Parameters: * none * * Returns: * OEMCrypto_DrmCertificate - means the device has a DRM certificate built * into the system. This cannot be used by level 1 devices. * OEMCrypto_Keybox - means the device has a unique keybox. For level 1 * devices this keybox must be securely installed by the device manufacturer. * OEMCrypto_OEMCertificate - means the device has a factory installed OEM * certificate. This is also called Provisioning 3.0. * * Threading: * This function may be called simultaneously with any session functions. * * Version: * This method is new API version 12. */ OEMCrypto_ProvisioningMethod OEMCrypto_GetProvisioningMethod(); /* * OEMCrypto_GetOEMPublicCertificate * * Description: * This function should place the OEM public certificate in the buffer * public_cert. After a call to this function, all methods using an RSA key * should use the OEM certificate’s private RSA key. See the discussion of * Provisioning 3.0 in the document "WV Modular DRM Security Itegration Guide * for Common Encryption (CENC)". * * If the buffer is not large enough, OEMCrypto should update * public_cert_length and return OEMCrypto_ERROR_SHORT_BUFFER. * * Parameters: * session (in) - this function affects the specified session only. * public_cert (out) - the buffer where the public certificate is stored. * public_cert_length (in/out) - on input, this is the available size of the * buffer. On output, this is the number of bytes needed for the * certificate. * * Returns: * OEMCrypto_SUCCESS * OEMCrypto_ERROR_NOT_IMPLEMENTED * OEMCrypto_ERROR_SHORT_BUFFER * * Threading: * This function may be called simultaneously with functions on other * sessions, but not with other functions on this session. * * Version: * This method is new API version 12. */ OEMCryptoResult OEMCrypto_GetOEMPublicCertificate(OEMCrypto_SESSION session, uint8_t* public_cert, size_t* public_cert_length); /* * OEMCrypto_LoadTestKeybox * * Description: * Temporarily use the standard test keybox in place of the factory * provisioned keybox for all functions that use keybox keys or data. This * allows a standard suite of unit tests to be run on a production device * without permanently changing the keybox. This keybox will persist until * the next call to OEMCrypto_Terminate or OEMCrypto_Initialize. Upon * initialization, revert to using the factory provisioned keybox. * * The test keybox can be found in the reference implementation. * * Parameters * none * * Returns * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_UNKNOWN_FAILURE * * Threading * This function is not called simultaneously with any other functions. * It will be called just after OEMCrypto_Initialize(). * * Version * This method is added in API version 10. */ OEMCryptoResult OEMCrypto_LoadTestKeybox(); /* * OEMCrypto_IsKeyboxValid * * Description: * Validate the Widevine Keybox stored on the device. * * The API performs two verification steps on the Keybox. It first verifies * the MAGIC field contains a valid signature (must be 'kbox'). The API then * computes the CRC using CRC-32 (Posix 1003.2 standard) and compares the * checksum to the CRC stored in the Keybox. The CRC is computed over the * entire Keybox excluding the 4 CRC bytes (i.e. Keybox[0..123]). * * Parameters: * none * * Threading: * This function may be called simultaneously with any session functions. * * Returns: * OEMCrypto_SUCCESS * OEMCrypto_ERROR_BAD_MAGIC * OEMCrypto_ERROR_BAD_CRC * * Version: * This method is supported by all API versions. */ OEMCryptoResult OEMCrypto_IsKeyboxValid(void); /* * OEMCrypto_GetDeviceID * * Description: * Retrieve the device's unique identifier from the Keybox. * * Parameters: * deviceId (out) - pointer to the buffer that receives the Device ID * idLength (in/out) - on input, size of the caller's device ID buffer. * On output, the number of bytes written into the buffer. * * Threading: * This function may be called simultaneously with any session functions. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_SHORT_BUFFER buffer is too small to return the device ID * OEMCrypto_ERROR_NO_DEVICEID failed to return Device Id * * Version: * This method is supported by all API versions. */ OEMCryptoResult OEMCrypto_GetDeviceID(uint8_t* deviceID, size_t* idLength); /* * OEMCrypto_GetKeyData * * Description: * Returns the Key Data field from the Keybox. The Key Data field does not * need to be encrypted by an OEM root key, but may be if desired. * * If the Key Data field was encrypted with an OEM root key when the Keybox * was stored on the device, then this function should decrypt it and return * the clear Key Data. If the Key Data was not encrypted, then this function * should just access and return the clear Key data. * * Parameters: * keyData (out) - pointer to a caller-managed buffer to hold the Key Data * field from the Keybox * dataLength (in/out) - on input, the allocated buffer size. On output, * the number of bytes in KeyData. * * Threading: * This function may be called simultaneously with any session functions. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_SHORT_BUFFER the buffer is too small to return the KeyData * OEMCrypto_ERROR_NO_KEYDATA failed to return KeyData * OEMCrypto_ERROR_NOT_IMPLEMENTED - device does not use keybox * * Version: * This method is supported by all API versions. */ OEMCryptoResult OEMCrypto_GetKeyData(uint8_t* keyData, size_t* keyDataLength); /* * OEMCrypto_GetRandom * * Description: * Return a buffer filled with hardware-generated random bytes. If the * hardware feature does not exist, return OEMCrypto_ERROR_RNG_NOT_SUPPORTED. * * Parameters: * randomData (out) - Pointer to caller-manager buffer that will receive the * random data. * dataLength (in) - Length of the random data buffer in bytes. * * Threading: * This function may be called simultaneously with any session functions. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_RNG_FAILED failed to generate random number * OEMCrypto_ERROR_RNG_NOT_SUPPORTED function not supported * OEMCrypto_ERROR_BUFFER_TOO_LARGE * * Buffer Sizes * OEMCrypto shall support dataLength of at least 32 bytes for random number * generation. * OEMCrypto shall return OEMCrypto_ERROR_BUFFER_TOO_LARGE if the buffer is * too large. * * Version: * This method is supported by all API versions. */ OEMCryptoResult OEMCrypto_GetRandom(uint8_t* randomData, size_t dataLength); /* * OEMCrypto_RewrapDeviceRSAKey30 * * Description: * This function is similar to RewrapDeviceRSAKey, except it uses the private * key from an OEM certificate to decrypt the message key instead of keys * derived from a keybox. Verifies an RSA provisioning response is valid and * corresponds to the previous provisioning request by checking the nonce. * The RSA private key is decrypted and stored in secure memory. The RSA key * is then re-encrypted and signed for storage on the filesystem. We * recommend that the OEM use an encryption key and signing key generated * using an algorithm at least as strong as that in GenerateDerivedKeys. * * After decrypting enc_rsa_key, If the first four bytes of the buffer are * the string “SIGN”, then the actual RSA key begins on the 9th byte of the * buffer. The second four bytes of the buffer is the 32 bit field * “allowed_schemes”, of type RSA_Padding_Scheme, which is used in * OEMCrypto_GenerateRSASignature. The value of allowed_schemes must also * be wrapped with RSA key. We recommend storing the magic string “SIGN” with * the key to distinguish keys that have a value for allowed_schemes from * those that should use the default allowed_schemes. Devices that do not * support the alternative signing algorithms may refuse to load these keys * and return an error of OEMCrypto_ERROR_NOT_IMPLEMENTED. The main use case * for these alternative signing algorithms is to support devices that use * x509 certificates for authentication when acting as a ChromeCast receiver. * This is not needed for devices that wish to send data to a ChromeCast. * * If the first four bytes of the buffer enc_rsa_key are not the string * “SIGN”, then the default value of allowed_schemes = 1 (kSign_RSASSA_PSS) * will be used. * * Verification and Algorithm: * The following checks should be performed. If any check fails, an error is * returned, and the key is not loaded. * 1. Verify that in_wrapped_rsa_key_length is large enough to hold the * rewrapped key, returning OEMCrypto_ERROR_SHORT_BUFFER otherwise. * 2. Verify that the nonce matches one generated by a previous call to * OEMCrypto_GenerateNonce(). The matching nonce shall be removed from the * nonce table. If there is no matching nonce, return * OEMCRYPTO_ERROR_INVALID_NONCE. * 3. Decrypt encrypted_message_key with the OEM certificate’s private RSA key * using RSA-OAEP into the buffer message_key. This message key is a 128 bit * AES key used only in step 4. This message_key should be kept in secure * memory and protected from the user. * 4. Decrypt enc_rsa_key into the buffer rsa_key using the message_key, which * was found in step 3. Use enc_rsa_key_iv as the initial vector for * AES_128-CBC mode, with PKCS#5 padding. The rsa_key should be kept in * secure memory and protected from the user. * 5. If the first four bytes of the buffer rsa_key are the string “SIGN”, * then the actual RSA key begins on the 9th byte of the buffer. The second * four bytes of the buffer is the 32 bit field “allowed_schemes”, of type * RSA_Padding_Scheme, which is used in OEMCrypto_GenerateRSASignature. * The value of allowed_schemes must also be wrapped with RSA key. We * recommend storing the magic string “SIGN” with the key to distinguish keys * that have a value for allowed_schemes from those that should use the * default allowed_schemes. Devices that do not support the alternative * signing algorithms may refuse to load these keys and return an error of * OEMCrypto_ERROR_NOT_IMPLEMENTED. The main use case for these alternative * signing algorithms is to support devices that use X.509 certificates for * authentication when acting as a ChromeCast receiver. This is not needed * for devices that wish to send data to a ChromeCast. * 6. If the first four bytes of the buffer rsa_key are not the string “SIGN”, * then the default value of allowed_schemes = 1 (kSign_RSASSA_PSS) will be * used. * 7. After possibly skipping past the first 8 bytes signifying the allowed * signing algorithm, the rest of the buffer rsa_key contains an RSA device * key in PKCS#8 binary DER encoded format. The OEMCrypto library shall * verify that this RSA key is valid. * 8. Re-encrypt the device RSA key with an internal key (such as the OEM key * or Widevine Keybox key) and the generated IV using AES-128-CBC with PKCS#5 * padding. * 9. Copy the rewrapped key to the buffer specified by wrapped_rsa_key and * the size of the wrapped key to wrapped_rsa_key_length. * * Parameters: * session (in) - crypto session identifier. * nonce (in) - The nonce provided in the provisioning response. * encrypted_message_key (in) - message_key encrypted by private key * - from OEM cert. * encrypted_message_key_length (in) - length of encrypted_message_key in * - bytes. * enc_rsa_key (in) - Encrypted device private RSA key received from * - the provisioning server. Format is PKCS#8 * - binary DER encoded, encrypted with message_key, * - using AES-128-CBC with PKCS#5 * - padding. Encrypted by message_key. * enc_rsa_key_length (in) - length of the encrypted RSA key, in bytes. * enc_rsa_key_iv (in) - IV for decrypting RSA key. Size is 128 bits. * wrapped_rsa_key (out) - pointer to buffer in which encrypted RSA key * - should be stored. May be null on the first call * - in order to find required buffer size. * wrapped_rsa_key_length (in/out) - length of the encrypted RSA key, in * - bytes. * * Threading: * This function may be called simultaneously with functions on other * sessions, but not with other functions on this session. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_NO_DEVICE_KEY * OEMCrypto_ERROR_INVALID_SESSION * OEMCrypto_ERROR_INVALID_RSA_KEY * OEMCrypto_ERROR_SIGNATURE_FAILURE * OEMCrypto_ERROR_INVALID_NONCE * OEMCrypto_ERROR_SHORT_BUFFER * OEMCrypto_ERROR_INSUFFICIENT_RESOURCES * OEMCrypto_ERROR_UNKNOWN_FAILURE * OEMCrypto_ERROR_BUFFER_TOO_LARGE * * Buffer Sizes * OEMCrypto shall support message sizes of at least 8 KiB. * OEMCrypto shall return OEMCrypto_ERROR_BUFFER_TOO_LARGE if the buffer is * larger than the supported size. * * Version: * This method is new in API version 12. */ OEMCryptoResult OEMCrypto_RewrapDeviceRSAKey30( OEMCrypto_SESSION session, const uint32_t* nonce, const uint8_t* encrypted_message_key, size_t encrypted_message_key_length, const uint8_t* enc_rsa_key, size_t enc_rsa_key_length, const uint8_t* enc_rsa_key_iv, uint8_t* wrapped_rsa_key, size_t* wrapped_rsa_key_length); /* * OEMCrypto_RewrapDeviceRSAKey * * Description: * This function is similar to RewrapDeviceRSAKey30, except it uses session * keys derived from the keybox instead of the OEM certificate. Verifies an * RSA provisioning response is valid and corresponds to the previous * provisioning request by checking the nonce. The RSA private key is * decrypted and stored in secure memory. The RSA key is then re-encrypted * and signed for storage on the filesystem. We recommend that the OEM use * an encryption key and signing key generated using an algorithm at least as * strong as that in GenerateDerivedKeys. * * After decrypting enc_rsa_key, If the first four bytes of the buffer are * the string “SIGN”, then the actual RSA key begins on the 9th byte of the * buffer. The second four bytes of the buffer is the 32 bit field * “allowed_schemes”, of type RSA_Padding_Scheme, which is used in * OEMCrypto_GenerateRSASignature. The value of allowed_schemes must also * be wrapped with RSA key. We recommend storing the magic string “SIGN” with * the key to distinguish keys that have a value for allowed_schemes from * those that should use the default allowed_schemes. Devices that do not * support the alternative signing algorithms may refuse to load these keys * and return an error of OEMCrypto_ERROR_NOT_IMPLEMENTED. The main use case * for these alternative signing algorithms is to support devices that use * x509 certificates for authentication when acting as a ChromeCast receiver. * This is not needed for devices that wish to send data to a ChromeCast. * * If the first four bytes of the buffer enc_rsa_key are not the string * “SIGN”, then the default value of allowed_schemes = 1 (kSign_RSASSA_PSS) * will be used. * * Verification and Algorithm: * The following checks should be performed. If any check fails, an error is * returned, and the key is not loaded. * 1. Check that all the pointer values passed into it are within the buffer * specified by message and message_length. * 2. Verify that in_wrapped_rsa_key_length is large enough to hold the * rewrapped key, returning OEMCrypto_ERROR_SHORT_BUFFER otherwise. * 3. Verify that the nonce matches one generated by a previous call to * OEMCrypto_GenerateNonce(). The matching nonce shall be removed from the * nonce table. If there is no matching nonce, return * OEMCRYPTO_ERROR_INVALID_NONCE. * 4. Verify the message signature, using the derived signing key * (mac_key[server]) from a previous call to OEMCrypto_GenerateDerivedKeys. * 5. Decrypt enc_rsa_key in the buffer rsa_key using the derived encryption * key (enc_key) from a previous call to OEMCrypto_GenerateDerivedKeys. Use * enc_rsa_key_iv as the initial vector for AES_128-CBC mode, with PKCS#5 * padding. The rsa_key should be kept in secure memory and protected from * the user. * 6. If the first four bytes of the buffer rsa_key are the string “SIGN”, then * the actual RSA key begins on the 9th byte of the buffer. The second four * bytes of the buffer is the 32 bit field “allowed_schemes”, of type * RSA_Padding_Scheme, which is used in OEMCrypto_GenerateRSASignature. * The value of allowed_schemes must also be wrapped with RSA key. We * recommend storing the magic string “SIGN” with the key to distinguish keys * that have a value for allowed_schemes from those that should use the * default allowed_schemes. Devices that do not support the alternative * signing algorithms may refuse to load these keys and return an error of * OEMCrypto_ERROR_NOT_IMPLEMENTED. The main use case for these alternative * signing algorithms is to support devices that use X.509 certificates for * authentication when acting as a ChromeCast receiver. This is not needed * for devices that wish to send data to a ChromeCast. * 7. If the first four bytes of the buffer rsa_key are not the string “SIGN”, * then the default value of allowed_schemes = 1 (kSign_RSASSA_PSS) will be * used. * 8. After possibly skipping past the first 8 bytes signifying the allowed * signing algorithm, the rest of the buffer rsa_key contains an RSA device * key in PKCS#8 binary DER encoded format. The OEMCrypto library shall * verify that this RSA key is valid. * 9. Re-encrypt the device RSA key with an internal key (such as the OEM key * or Widevine Keybox key) and the generated IV using AES-128-CBC with PKCS#5 * padding. * 10. Copy the rewrapped key to the buffer specified by wrapped_rsa_key and * the size of the wrapped key to wrapped_rsa_key_length. * * Parameters: * session (in) - crypto session identifier. * message (in) - pointer to memory containing message to be * - verified. * message_length (in) - length of the message, in bytes. * signature (in) - pointer to memory containing the HMAC-SHA256 * - signature for message, received from the * - provisioning server. * signature_length (in) - length of the signature, in bytes. * nonce (in) - The nonce provided in the provisioning response. * enc_rsa_key (in) - Encrypted device private RSA key received from * - the provisioning server. Format is PKCS#8 * - binary DER encoded, encrypted with the derived * - encryption key, using AES-128-CBC with PKCS#5 * - padding. * enc_rsa_key_length (in) - length of the encrypted RSA key, in bytes. * enc_rsa_key_iv (in) - IV for decrypting RSA key. Size is 128 bits. * wrapped_rsa_key (out) - pointer to buffer in which encrypted RSA key * - should be stored. May be null on the first call * - in order to find required buffer size. * wrapped_rsa_key_length (in/out) - length of the encrypted RSA key, in * - bytes. * * Threading: * This function may be called simultaneously with functions on other * sessions, but not with other functions on this session. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_NO_DEVICE_KEY * OEMCrypto_ERROR_INVALID_SESSION * OEMCrypto_ERROR_INVALID_RSA_KEY * OEMCrypto_ERROR_SIGNATURE_FAILURE * OEMCrypto_ERROR_INVALID_NONCE * OEMCrypto_ERROR_SHORT_BUFFER * OEMCrypto_ERROR_INSUFFICIENT_RESOURCES * OEMCrypto_ERROR_UNKNOWN_FAILURE * OEMCrypto_ERROR_BUFFER_TOO_LARGE * * Buffer Sizes * OEMCrypto shall support message sizes of at least 8 KiB. * OEMCrypto shall return OEMCrypto_ERROR_BUFFER_TOO_LARGE if the buffer is * larger than the supported size. * * Version: * This method changed in API version 9. */ OEMCryptoResult OEMCrypto_RewrapDeviceRSAKey( OEMCrypto_SESSION session, const uint8_t* message, size_t message_length, const uint8_t* signature, size_t signature_length, const uint32_t* nonce, const uint8_t* enc_rsa_key, size_t enc_rsa_key_length, const uint8_t* enc_rsa_key_iv, uint8_t* wrapped_rsa_key, size_t* wrapped_rsa_key_length); /* * OEMCrypto_LoadDeviceRSAKey * * Description: * Loads a wrapped RSA private key to secure memory for use by this session * in future calls to OEMCrypto_GenerateRSASignature. The wrapped RSA key * will be the one verified and wrapped by OEMCrypto_RewrapDeviceRSAKey. The * RSA private key should be stored in secure memory. * * If the bit field "allowed_schemes" was wrapped with this RSA key, its * value will be loaded and stored with the RSA key. If there was not bit * field wrapped with the RSA key, the key will use a default value of 1 = * RSASSA-PSS with SHA1. * * Verification: * The following checks should be performed. If any check fails, an error is * returned, and the RSA key is not loaded. * 1. The wrapped key has a valid signature, as described in * RewrapDeviceRSAKey. * 2. The decrypted key is a valid private RSA key. * 3. If a value for allowed_schemes is included with the key, it is a valid * value. * * Parameters: * session (in) - crypto session identifier. * wrapped_rsa_key (in) - wrapped device RSA key stored on the device. * - Format is PKCS#8, binary DER encoded, and * - encrypted with a key internal to the * - OEMCrypto instance, using AES-128-CBC with * - PKCS#5 padding. This is the wrapped key * - generated by OEMCrypto_RewrapDeviceRSAKey. * wrapped_rsa_key_length (in) - length of the wrapped key buffer, in bytes. * * Threading: * This function may be called simultaneously with functions on other * sessions, but not with other functions on this session. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_NO_DEVICE_KEY * OEMCrypto_ERROR_INVALID_SESSION * OEMCrypto_ERROR_INVALID_RSA_KEY * OEMCrypto_ERROR_INSUFFICIENT_RESOURCES * OEMCrypto_ERROR_UNKNOWN_FAILURE * * Version: * This method changed in API version 9. */ OEMCryptoResult OEMCrypto_LoadDeviceRSAKey(OEMCrypto_SESSION session, const uint8_t* wrapped_rsa_key, size_t wrapped_rsa_key_length); /* * OEMCrypto_LoadTestRSAKey * * Description: * Temporarily use the standard test RSA key. This function is only required * for platforms that do not use a keybox, but have an RSA certificate baked * in. This allows a standard suite of unit tests to be run on a production * device without permanently changing the certificate. This RSA key will * persist until the next call to OEMCrypto_Terminate or * OEMCrypto_Initialize. * * The test RSA key can be found in the reference implementation. * * Parameters * none * * Returns * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_UNKNOWN_FAILURE * * Threading * This function is not called simultaneously with any other functions. * It will be called just after OEMCrypto_OpenSession(). * * Version * This method is added in API version 10. */ OEMCryptoResult OEMCrypto_LoadTestRSAKey(); /* * OEMCrypto_GenerateRSASignature * * Description: * The OEMCrypto_GenerateRSASignature method is used to sign messages using * the device private RSA key, specifically, it is used to sign the initial * license request. Refer to the License Request Signed by RSA Certificate * section above for more details. * * If this function is called after OEMCrypto_LoadDeviceRSAKey for the same * session, then this function should use the device RSA key that was loaded. * If this function is called after a call to * OEMCrypto_GetOEMPublicCertificate for the same session, then this function * should use the RSA private key associated with the OEM certificate. The * only padding scheme that is valid for the OEM certificate is * 0x1 - RSASSA-PSS with SHA1. Any other padding scheme must generate an * error. * * For devices that wish to be CAST receivers, there is a new RSA padding * scheme. The padding_scheme parameter indicates which hashing and padding * is to be applied to the message so as to generate the encoded message (the * modulus-sized block to which the integer conversion and RSA decryption is * applied). The following values are defined: * 0x1 - RSASSA-PSS with SHA1. * 0x2 - PKCS1 with block type 1 padding (only). * * In the first case, a hash algorithm (SHA1) is first applied to the * message, whose length is not otherwise restricted. In the second case, the * "message" is already a digest, so no further hashing is applied, and the * message_length can be no longer than 83 bytes. If the message_length is * greater than 83 bytes OEMCrypto_ERROR_SIGNATURE_FAILURE shall be returned. * * The second padding scheme is for devices that use x509 certificates for * authentication. The main example is devices that work as a Cast receiver, * like a ChromeCast, not for devices that wish to send to the Cast device, * such as almost all Android devices. OEMs that do not support x509 * certificate authentication need not implement the second scheme and can * return OEMCrypto_ERROR_NOT_IMPLEMENTED. * * Verification: * The bitwise AND of the parameter padding_scheme and the RSA key’s * allowed_schemes is computed. If this value is 0, then the signature is not * computed and the error OEMCrypto_ERROR_INVALID_RSA_KEY is returned. * * Parameters: * session (in) - crypto session identifier. * message (in) - pointer to memory containing message to be * - signed. * message_length (in) - length of the message, in bytes. * signature (out) - buffer to hold the message signature. On * - return, it will contain the message signature * - generated with the device private RSA key using * - RSASSA-PSS. * signature_length (in/out) - (in) length of the signature buffer, in bytes. * - (out) actual length of the signature * padding_scheme (in) - specify which scheme to use for the signature. * * Threading: * This function may be called simultaneously with functions on other * sessions, but not with other functions on this session. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_INVALID_SESSION * OEMCrypto_ERROR_INVALID_CONTEXT * OEMCrypto_ERROR_SHORT_BUFFER if the signature buffer is too small. * OEMCrypto_ERROR_INVALID_RSA_KEY * OEMCrypto_ERROR_INSUFFICIENT_RESOURCES * OEMCrypto_ERROR_UNKNOWN_FAILURE * OEMCrypto_ERROR_NOT_IMPLEMENTED - if algorithm > 0, and the device does not * support that algorithm. * OEMCrypto_ERROR_BUFFER_TOO_LARGE * * Buffer Sizes * OEMCrypto shall support message sizes of at least 8 KiB. * OEMCrypto shall return OEMCrypto_ERROR_BUFFER_TOO_LARGE if the buffer is * larger than the supported size. * * Version: * This method changed in API version 9. */ OEMCryptoResult OEMCrypto_GenerateRSASignature( OEMCrypto_SESSION session, const uint8_t* message, size_t message_length, uint8_t* signature, size_t* signature_length, RSA_Padding_Scheme padding_scheme); /* * OEMCrypto_DeriveKeysFromSessionKey * * Description: * Generates three secondary keys -- mac_key_server, mac_key_client, and * encrypt_key -- for handling signing and content key decryption under the * license server protocol for AES CTR mode. * * This function is similar to OEMCrypto_GenerateDerivedKeys, except that it * uses a session key to generate the secondary keys instead of the Widevine * Keybox device key. These two keys will be stored in secure memory until * the next call to LoadKeys. The session key is passed in encrypted by the * device RSA public key, and must be decrypted with the RSA private key * before use. Once the enc_key and mac_keys have been generated, all calls * to LoadKeys and RefreshKeys proceed in the same manner for license * requests using RSA or using a Widevine keybox token. * * Verification: * If the RSA key’s allowed_schemes is not kSign_RSASSA_PSS, then no keys are * derived and the error OEMCrypto_ERROR_INVALID_RSA_KEY is returned. An RSA * key cannot be used for both deriving session keys and also for PKCS1 * signatures. * * Parameters: * session (in) - crypto session identifier. * enc_session_key (in) - session key, encrypted with the device RSA * - key (from the device certifcate) using * - RSA-OAEP. * enc_session_key_length (in) - length of session_key, in bytes. * mac_key_context (in) - pointer to memory containing context data for * - computing the HMAC generation key. * mac_key_context_length (in) - length of the HMAC key context data, in * - bytes. * enc_key_context (in) - pointer to memory containing context data for * - computing the encryption key. * enc_key_context_length (in) - length of the encryption key context data, in * - bytes. * * Threading: * This function may be called simultaneously with functions on other * sessions, but not with other functions on this session. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_DEVICE_NOT_RSA_PROVISIONED * OEMCrypto_ERROR_INVALID_SESSION * OEMCrypto_ERROR_INVALID_CONTEXT * OEMCrypto_ERROR_INSUFFICIENT_RESOURCES * OEMCrypto_ERROR_UNKNOWN_FAILURE * OEMCrypto_ERROR_BUFFER_TOO_LARGE * * Buffer Sizes * OEMCrypto shall support message sizes of at least 8 KiB. * OEMCrypto shall return OEMCrypto_ERROR_BUFFER_TOO_LARGE if the buffer is * larger than the supported size. * * Version: * This method changed in API version 9. */ OEMCryptoResult OEMCrypto_DeriveKeysFromSessionKey( OEMCrypto_SESSION session, const uint8_t* enc_session_key, size_t enc_session_key_length, const uint8_t* mac_key_context, size_t mac_key_context_length, const uint8_t* enc_key_context, size_t enc_key_context_length); /* * OEMCrypto_APIVersion() * * Description: * This function returns the current API version number. Because this * API is part of a shared library, the version number allows the calling * application to avoid version mis-match errors. * * There is a possibility that some API methods will be backwards compatible, * or backwards compatible at a reduced security level. * * There is no plan to introduce forward-compatibility. Applications will * reject a library with a newer version of the API. * * Parameters: * none * * Threading: * This function may be called simultaneously with any other functions. * * Returns: * The supported API, as specified in the header file OEMCryptoCENC.h. * * Version: * This method should change in all API versions. */ uint32_t OEMCrypto_APIVersion(); /** * OEMCrypto_Security_Patch_Level() * * Description: * This function returns the current patch level of the software running in * the trusted environment. The patch level is defined by the OEM, and is * only incremented when a security update has been added. * * Parameters: * none * * Returns: * The OEM defined version number. * * Threading: * This function may be called simultaneously with any other functions. * * Version: * This method was introduced in API version 11. */ uint8_t OEMCrypto_Security_Patch_Level(); /* * OEMCrypto_SecurityLevel() * * Description: * This function returns the security level of the OEMCrypto library. * * Since this function is spoofable, it is not relied on for security * purposes. It is for information only. * * Returns: * A null terminated string. Useful values are "L1", "L2" or "L3". * * Threading: * This function may be called simultaneously with any other functions. * * Version: * This method changed in API version 6. */ const char* OEMCrypto_SecurityLevel(); /* * OEMCrypto_GetHDCPCapability() * * Description: * Returns the maximum HDCP version supported by the device, and the HDCP * version supported by the device and any connected display. * * Parameters: * current (out) - this is the current HDCP version, based on the device * itself, and the display to which it is connected. * maximum (out) - this is the maximum supported HDCP version for the device, * ignoring any attached device. * * Threading: * This function may be called simultaneously with any other functions. * * Returns: * OEMCrypto_SUCCESS * OEMCrypto_ERROR_UNKNOWN_FAILURE * * Version: * This method changed in API version 10. */ OEMCryptoResult OEMCrypto_GetHDCPCapability(OEMCrypto_HDCP_Capability* current, OEMCrypto_HDCP_Capability* maximum); /* * OEMCrypto_SupportsUsageTable() * * Description: * This is used to determine if the device can support a usage table. Since * this function is spoofable, it is not relied on for security purposes. It * is for information only. The usage table is described in the section * above. * * Parameters: * none * * Threading: * This function may be called simultaneously with any other functions. * * Returns: * Returns true if the device can maintain a usage table. Returns false * otherwise. * * Version: * This method changed in API version 9. */ bool OEMCrypto_SupportsUsageTable(); /* * OEMCrypto_IsAntiRollbackHwPresent() * * Description: * Indicate whether there is hardware protection to prevent the rollback of * the usage table. For example, this is true if the usage table is stored * entirely on a secure file system that the user cannot read or write to. * Another example is if the usage table has a generation number and the * generation number is stored in secure memory that is not user accessible. * * Parameters: * none. * * Threading: * This function may be called simultaneously with any other functions. * * Returns: * Returns true if oemcrypto uses anti-rollback hardware. Returns false * otherwise. * * Version: * This method is added in API version 10. */ bool OEMCrypto_IsAntiRollbackHwPresent(); /* * OEMCRYPTO_GetNumberOfOpenSessions() * * Description: * Returns the current number of open OEMCrypto sessions. The CDM and * OEMCrypto consumers can query this value so they can use resources more * effectively. * * Parameters: * count (out) - the current number of OEMCrypto sessions. * * Threading: * This function may be called simultaneously with any other functions. * * Returns: * OEMCrypto_SUCCESS * OEMCrypto_ERROR_UNKNOWN_FAILURE * * Version: * This method is added in API version 10. */ OEMCryptoResult OEMCrypto_GetNumberOfOpenSessions(size_t* count); /* * OEMCRYPTO_GetMaxNumberOfSessions() * * Description: * Returns the maximum number of concurrent OEMCrypto sessions supported by * the device. The CDM and OEMCrypto consumers can query this value so they * can use resources more effectively. If the maximum number of sessions * depends on a dynamically allocated shared resource, the returned value * should be a best estimate of the maximum number of sessions. * * OEMCrypto shall support a minimum of 10 sessions. Some applications use * multiple sessions to pre-fetch licenses, so high end devices should * support more sessions -- we recommend a minimum of 50 sessions. * * Parameters: * maximum (out) - the maximum number of OEMCrypto sessions supported by the * device. * * Threading: * This function may be called simultaneously with any other functions. * * Returns: * OEMCrypto_SUCCESS * OEMCrypto_ERROR_UNKNOWN_FAILURE * * Version: * This method is added in API version 10. */ OEMCryptoResult OEMCrypto_GetMaxNumberOfSessions(size_t* max); /* * OEMCrypto_Generic_Encrypt * * Description: * This function encrypts a generic buffer of data using the current key. * * If the session has an entry in the Usage Table, then OEMCrypto will update * the time_of_last_decrypt. If the status of the entry is "unused", then * change the status to "active" and set the time_of_first_decrypt. * * Verification: * The following checks should be performed. If any check fails, an error is * returned, and the data is not encrypted. * 1. The control bit for the current key shall have the Allow_Encrypt * set. If not, return OEMCrypto_ERROR_UNKNOWN_FAILURE. * 2. If the current key’s control block has a nonzero Duration field, then * the API shall verify that the duration is greater than the session’s * elapsed time clock. If not, return OEMCrypto_ERROR_KEY_EXPIRED. * 3. If the current session has an entry in the Usage Table, and the status * of that entry is "inactive", then return OEMCrypto_ERROR_INVALID_SESSION. * * Parameters: * session (in) - crypto session identifier. * in_buffer (in) - pointer to memory containing data to be encrypted. * buffer_length (in) - length of the buffer, in bytes. * iv (in) - IV for encrypting data. Size is specified by the algorithm. * algorithm (in) - Specifies which encryption algorithm to use. See * OEMCrypto_Algorithm for valid values. * out_buffer (out) - pointer to buffer in which encrypted data should be * stored. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_KEY_EXPIRED * OEMCrypto_ERROR_NO_DEVICE_KEY * OEMCrypto_ERROR_INVALID_SESSION * OEMCrypto_ERROR_INSUFFICIENT_RESOURCES * OEMCrypto_ERROR_UNKNOWN_FAILURE * OEMCrypto_ERROR_BUFFER_TOO_LARGE * * Buffer Sizes * OEMCrypto shall support buffer sizes of at least 100 KiB for generic * crypto operations. * OEMCrypto shall return OEMCrypto_ERROR_BUFFER_TOO_LARGE if the buffer is * larger than the supported size. * * Threading: * This function may be called simultaneously with functions on other sessions, * but not with other functions on this session. * * Version: * This method changed in API version 9. */ OEMCryptoResult OEMCrypto_Generic_Encrypt( OEMCrypto_SESSION session, const uint8_t* in_buffer, size_t buffer_length, const uint8_t* iv, OEMCrypto_Algorithm algorithm, uint8_t* out_buffer); /* * OEMCrypto_Generic_Decrypt * * Description: * This function decrypts a generic buffer of data using the current key. * * If the session has an entry in the Usage Table, then OEMCrypto will update * the time_of_last_decrypt. If the status of the entry is "unused", then * change the status to "active" and set the time_of_first_decrypt. * * Verification: * The following checks should be performed. If any check fails, an error is * returned, and the data is not decrypted. * 1. The control bit for the current key shall have the Allow_Decrypt set. If * not, return OEMCrypto_ERROR_DECRYPT_FAILED. * 2. If the current key’s control block has the Data_Path_Type bit set, then * return OEMCrypto_ERROR_DECRYPT_FAILED. * 3. If the current key’s control block has a nonzero Duration field, then * the API shall verify that the duration is greater than the session’s * elapsed time * clock. If not, return OEMCrypto_ERROR_KEY_EXPIRED. * 4. If the current session has an entry in the Usage Table, and the status * of that entry is "inactive", then return OEMCrypto_ERROR_INVALID_SESSION. * * Parameters: * session (in) - crypto session identifier. * in_buffer (in) - pointer to memory containing data to be encrypted. * buffer_length (in) - length of the buffer, in bytes. The algorithm may * restrict buffer_length to be a multiple of block size. * iv (in) - IV for encrypting data. Size is 128 bits. * algorithm (in) - Specifies which encryption algorithm to use. * out_buffer (out) - pointer to buffer in which decrypted data should be * stored. * * Threading: * This function may be called simultaneously with functions on other * sessions, but not with other functions on this session. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_KEY_EXPIRED * OEMCrypto_ERROR_DECRYPT_FAILED * OEMCrypto_ERROR_NO_DEVICE_KEY * OEMCrypto_ERROR_INVALID_SESSION * OEMCrypto_ERROR_INSUFFICIENT_RESOURCES * OEMCrypto_ERROR_UNKNOWN_FAILURE * OEMCrypto_ERROR_BUFFER_TOO_LARGE * * Buffer Sizes * OEMCrypto shall support buffer sizes of at least 100 KiB for generic * crypto operations. * OEMCrypto shall return OEMCrypto_ERROR_BUFFER_TOO_LARGE if the buffer is * larger than the supported size. * * Version: * This method changed in API version 9. */ OEMCryptoResult OEMCrypto_Generic_Decrypt( OEMCrypto_SESSION session, const uint8_t* in_buffer, size_t buffer_length, const uint8_t* iv, OEMCrypto_Algorithm algorithm, uint8_t* out_buffer); /* * OEMCrypto_Generic_Sign * * Description: * This function signs a generic buffer of data using the current key. * * If the session has an entry in the Usage Table, then OEMCrypto will update * the time_of_last_decrypt. If the status of the entry is "unused", then * change the status to "active" and set the time_of_first_decrypt. * * Verification: * The following checks should be performed. If any check fails, an error is * returned, and the data is not signed. * 1. The control bit for the current key shall have the Allow_Sign set. * 2. If the current key’s control block has a nonzero Duration field, then * the API shall verify that the duration is greater than the session’s * elapsed time clock. If not, return OEMCrypto_ERROR_KEY_EXPIRED. * 3. If the current session has an entry in the Usage Table, and the status of * that entry is "inactive", then return OEMCrypto_ERROR_INVALID_SESSION. * * Parameters: * session (in) - crypto session identifier. * in_buffer (in) - pointer to memory containing data to be encrypted. * buffer_length (in) - length of the buffer, in bytes. * algorithm (in) - Specifies which algorithm to use. * signature (out) - pointer to buffer in which signature should be * stored. May be null on the first call in order to find required buffer * size. * signature_length (in/out) - (in) length of the signature buffer, in bytes. * (out) actual length of the signature * * * * Threading: * This function may be called simultaneously with functions on other * sessions, but not with other functions on this session. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_KEY_EXPIRED * OEMCrypto_ERROR_SHORT_BUFFER if signature buffer is not large enough to * hold the output signature. * OEMCrypto_ERROR_NO_DEVICE_KEY * OEMCrypto_ERROR_INVALID_SESSION * OEMCrypto_ERROR_INSUFFICIENT_RESOURCES * OEMCrypto_ERROR_UNKNOWN_FAILURE * OEMCrypto_ERROR_BUFFER_TOO_LARGE * * Buffer Sizes * OEMCrypto shall support buffer sizes of at least 100 KiB for generic * crypto operations. * OEMCrypto shall return OEMCrypto_ERROR_BUFFER_TOO_LARGE if the buffer is * larger than the supported size. * * Version: * This method changed in API version 9. */ OEMCryptoResult OEMCrypto_Generic_Sign(OEMCrypto_SESSION session, const uint8_t* in_buffer, size_t buffer_length, OEMCrypto_Algorithm algorithm, uint8_t* signature, size_t* signature_length); /* * OEMCrypto_Generic_Verify * * Description: * This function verifies the signature of a generic buffer of data using the * current key. * * If the session has an entry in the Usage Table, then OEMCrypto will update * the time_of_last_decrypt. If the status of the entry is "unused", then * change the status to "active" and set the time_of_first_decrypt. * * Verification: * The following checks should be performed. If any check fails, an error is * returned. * 1. The control bit for the current key shall have the Allow_Verify set. * 2. The signature of the message shall be computed, and the API shall verify * the computed signature matches the signature passed in. If not, return * OEMCrypto_ERROR_SIGNATURE_FAILURE. * 3. The signature verification shall use a constant-time algorithm (a * signature mismatch will always take the same time as a successful * comparison). * 4. If the current key’s control block has a nonzero Duration field, then * the API shall verify that the duration is greater than the session’s * elapsed time clock. If not, return OEMCrypto_ERROR_KEY_EXPIRED. * 5. If the current session has an entry in the Usage Table, and the status * of that entry is "inactive", then return OEMCrypto_ERROR_INVALID_SESSION. * * Parameters: * session (in) - crypto session identifier. * in_buffer (in) - pointer to memory containing data to be encrypted. * buffer_length (in) - length of the buffer, in bytes. * algorithm (in) - Specifies which algorithm to use. * signature (in) - pointer to buffer in which signature resides. * signature_length (in) - length of the signature buffer, in bytes. * * Threading: * This function may be called simultaneously with functions on other * sessions, but not with other functions on this session. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_KEY_EXPIRED * OEMCrypto_ERROR_SIGNATURE_FAILURE * OEMCrypto_ERROR_NO_DEVICE_KEY * OEMCrypto_ERROR_INVALID_SESSION * OEMCrypto_ERROR_INSUFFICIENT_RESOURCES * OEMCrypto_ERROR_UNKNOWN_FAILURE * OEMCrypto_ERROR_BUFFER_TOO_LARGE * * Buffer Sizes * OEMCrypto shall support buffer sizes of at least 100 KiB for generic * crypto operations. * OEMCrypto shall return OEMCrypto_ERROR_BUFFER_TOO_LARGE if the buffer is * larger than the supported size. * * Version: * This method changed in API version 9. */ OEMCryptoResult OEMCrypto_Generic_Verify(OEMCrypto_SESSION session, const uint8_t* in_buffer, size_t buffer_length, OEMCrypto_Algorithm algorithm, const uint8_t* signature, size_t signature_length); /* * OEMCrypto_UpdateUsageTable * * Description: * OEMCrypto should propagate values from all open sessions to the Session * Usage Table. If any values have changed, increment the generation number, * sign, and save the table. During playback, this function will be called * approximately once per minute. * * Devices that do not implement a Session Usage Table may return * OEMCrypto_ERROR_NOT_IMPLEMENTED. * * Parameters: * none * * Threading: * This function will not be called simultaneously with any session functions. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_NOT_IMPLEMENTED * OEMCrypto_ERROR_UNKNOWN_FAILURE * * Version: * This method changed in API version 9. */ OEMCryptoResult OEMCrypto_UpdateUsageTable(); /* * OEMCrypto_DeactivateUsageEntry * * Description: * Find the entry in the Usage Table with a matching PST. Mark the status of * that entry as "inactive". If it corresponds to an open session, the status * of that session will also be marked as "inactive". Then OEMCrypto will * increment Usage Table’s generation number, sign, encrypt, and save the * Usage Table. * * If no entry in the Usage Table has a matching PST, return the error * OEMCrypto_ERROR_INVALID_CONTEXT. * * Devices that do not implement a Session Usage Table may return * OEMCrypto_ERROR_NOT_IMPLEMENTED. * * Parameters: * pst (in) - pointer to memory containing Provider Session Token. * pst_length (in) - length of the pst, in bytes. * * Threading: * This function will not be called simultaneously with any session functions. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_INVALID_CONTEXT - no entry has matching PST. * OEMCrypto_ERROR_NOT_IMPLEMENTED * OEMCrypto_ERROR_UNKNOWN_FAILURE * OEMCrypto_ERROR_BUFFER_TOO_LARGE * * Buffer Sizes * OEMCrypto shall support pst sizes of at least 255 bytes. * OEMCrypto shall return OEMCrypto_ERROR_BUFFER_TOO_LARGE if the buffer is * too large. * * Version: * This method changed in API version 9. */ OEMCryptoResult OEMCrypto_DeactivateUsageEntry(const uint8_t* pst, size_t pst_length); /* * OEMCrypto_ReportUsage * * Description: * If the buffer_length is not sufficient to hold a report structure, set * buffer_length and return OEMCrypto_ERROR_SHORT_BUFFER. * * If no entry in the Usage Table has a matching PST, return the error * OEMCrypto_ERROR_INVALID_CONTEXT. * * OEMCrypto will increment Usage Table’s generation number, sign, encrypt, * and save the Usage Table. This is done, even though the table has not * changed, so that a single rollback cannot undo a call to * DeactivateUsageEntry and still report that license as inactive. * * The pst_report is filled out by subtracting the times un the Usage Table * from the current time on the secure clock. This is done in case the secure * clock is not using UTC time, but is instead using something like seconds * since clock installed. * * Valid values for status are: * 0 = kUnused -- the keys have not been used to decrypt. * 1 = kActive -- the keys have been used, and have not been deactivated. * 2 = kInactive -- the keys have been marked inactive. * * The clock_security_level is reported as follows: * 0 = Insecure Clock - clock just uses system time. * 1 = Secure Timer - clock uses secure timer, which cannot be modified by * user software, when OEMCrypto is active and the system time when * OEMCrypto is inactive. * 2 = Software Secure Clock - clock cannot be modified by user software * when OEMCrypto is active or inactive. * 3 = Hardware Secure Clock - clock cannot be modified by user software * and there are security features that prevent the user from modifying the * clock in hardware, such as a tamper proof battery. * * After pst_report has been filled in, the HMAC SHA1 signature is computed * for the buffer from bytes 20 to the end of the pst field. The signature is * computed using the client_mac_key which is stored in the usage table. The * HMAC SHA1 signature is used to prevent a rogue application from using * OMECrypto_GenerateSignature to forge a Usage Report. * * This function also copies the client_mac_key and server_mac_key from the * Usage Table entry to the session. They will be used to verify a signature * in OEMCrypto_DeleteUsageEntry below. This session will be associated with * the entry in the Usage Table. * * Devices that do not implement a Session Usage Table may return * OEMCrypto_ERROR_NOT_IMPLEMENTED. * * Parameters: * session (in) - handle for the session to be used. * pst (in) - pointer to memory containing Provider Session Token. * pst_length (in) - length of the pst, in bytes. * buffer (out) - pointer to buffer in which usage report should be * stored. May be null on the first call in order to find required buffer * size. * buffer_length (in/out) - (in) length of the report buffer, in bytes. * (out) actual length of the report * * Threading: * This function will not be called simultaneously with any session functions. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_SHORT_BUFFER if report buffer is not large enough to hold * the output signature. * OEMCrypto_ERROR_INVALID_SESSION no open session with that id. * OEMCrypto_ERROR_INVALID_CONTEXT - no entry has matching PST. * OEMCrypto_ERROR_NOT_IMPLEMENTED * OEMCrypto_ERROR_UNKNOWN_FAILURE * OEMCrypto_ERROR_BUFFER_TOO_LARGE * * Buffer Sizes * OEMCrypto shall support pst sizes of at least 255 bytes. * OEMCrypto shall return OEMCrypto_ERROR_BUFFER_TOO_LARGE if the buffer is * too large. * * Version: * This method changed in API version 9. */ OEMCryptoResult OEMCrypto_ReportUsage(OEMCrypto_SESSION session, const uint8_t* pst, size_t pst_length, OEMCrypto_PST_Report* buffer, size_t* buffer_length); /* * OEMCrypto_DeleteUsageEntry * * Description: * This function verifies the signature of the given message using the * sessions mac_key[server] and the algorithm HMAC-SHA256, and then deletes * an entry from the session table. The session should already be associated * with the given entry, from a previous call to OEMCrypto_ReportUsage. * * After performing all verification listed below, and deleting the entry * from the Usage Table, OEMCrypto will increment Usage Table’s generation * number, and then sign, encrypt, and save the Usage Table. * * The signature verification shall use a constant-time algorithm (a signature * mismatch will always take the same time as a successful comparison). * * Devices that do not implement a Session Usage Table may return * OEMCrypto_ERROR_NOT_IMPLEMENTED. * * Verification: * The following checks should be performed. If any check fails, an error is * returned. * 1. The pointer pst is not null, and points inside the message. If not, * return OEMCrypto_ERROR_UNKNOWN_FAILURE. * 2. The signature of the message shall be computed, and the API shall * verify the computed signature matches the signature passed in. The * signature will be computed using HMAC-SHA256 and the mac_key_server. If * they do not match, return OEMCrypto_ERROR_SIGNATURE_FAILURE. * 3. If the session is not associated with an entry in the Usage Table, * return OEMCrypto_ERROR_UNKNOWN_FAILURE. * 4. If the pst passed in as a parameter does not match that in the Usage * Table, return OEMCrypto_ERROR_UNKNOWN_FAILURE. * * Parameters: * session (in) - handle for the session to be used. * pst (in) - pointer to memory containing Provider Session Token. * pst_length (in) - length of the pst, in bytes. * message (in) - pointer to memory containing message to be verified. * message_length (in) - length of the message, in bytes. * signature (in) - pointer to memory containing the signature. * signature_length (in) - length of the signature, in bytes. * * Threading: * This function will not be called simultaneously with any session functions. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_INVALID_SESSION no open session with that id. * OEMCrypto_ERROR_SIGNATURE_FAILURE * OEMCrypto_ERROR_NOT_IMPLEMENTED * OEMCrypto_ERROR_UNKNOWN_FAILURE * OEMCrypto_ERROR_BUFFER_TOO_LARGE * * Buffer Sizes * OEMCrypto shall support pst sizes of at least 255 bytes. * OEMCrypto shall return OEMCrypto_ERROR_BUFFER_TOO_LARGE if the buffer is * too large. * * Version: * This method changed in API version 9. */ OEMCryptoResult OEMCrypto_DeleteUsageEntry( OEMCrypto_SESSION session, const uint8_t* pst, size_t pst_length, const uint8_t* message, size_t message_length, const uint8_t* signature, size_t signature_length); /* * OEMCrypto_ForceDeleteUsageEntry * * Description: * This function deletes an entry from the session usage table. This will be * used for stale entries without a signed request from the server. * * After performing all verification listed below, and deleting the entry from * the Usage Table, OEMCrypto will increment the Usage Table’s generation * number, and then sign, encrypt, and save the Usage Table. * * Devices that do not implement a Session Usage Table may return * OEMCrypto_ERROR_NOT_IMPLEMENTED. * * Verification * The following checks should be performed. If any check fails, an error is * returned. * 1) The pointer pst is not null. If not, return * OEMCrypto_ERROR_UNKNOWN_FAILURE. * * Parameters * pst (in) - pointer to memory containing Provider Session Token. * pst_length (in) - length of the pst, in bytes. * * Returns * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_NOT_IMPLEMENTED * OEMCrypto_ERROR_UNKNOWN_FAILURE * OEMCrypto_ERROR_BUFFER_TOO_LARGE * * Buffer Sizes * OEMCrypto shall support pst sizes of at least 255 bytes. * OEMCrypto shall return OEMCrypto_ERROR_BUFFER_TOO_LARGE if the buffer is * too large. * * Threading * This function will not be called simultaneously with any session functions. * * Version * This method changed in API version 10. */ OEMCryptoResult OEMCrypto_ForceDeleteUsageEntry(const uint8_t* pst, size_t pst_length); /* * OEMCrypto_DeleteUsageTable * * Description: * This is called when the CDM system believes there are major problems or * resource issues. The entire table should be cleaned and a new table should * be created. This is the same as calling ForceDeleteUsageEntry on all * entries. * * Parameters: * none * * Threading: * This function will not be called simultaneously with any session functions. * * Returns: * OEMCrypto_SUCCESS success * OEMCrypto_ERROR_NOT_IMPLEMENTED * OEMCrypto_ERROR_UNKNOWN_FAILURE * * Version: * This method changed in API version 9. */ OEMCryptoResult OEMCrypto_DeleteUsageTable(); #ifdef __cplusplus } #endif #endif // OEMCRYPTO_CENC_H_