| /** |
| * \file psa/crypto_se_driver.h |
| * \brief PSA external cryptoprocessor driver module |
| * |
| * This header declares types and function signatures for cryptography |
| * drivers that access key material via opaque references. |
| * This is meant for cryptoprocessors that have a separate key storage from the |
| * space in which the PSA Crypto implementation runs, typically secure |
| * elements (SEs). |
| * |
| * This file is part of the PSA Crypto Driver HAL (hardware abstraction layer), |
| * containing functions for driver developers to implement to enable hardware |
| * to be called in a standardized way by a PSA Cryptography API |
| * implementation. The functions comprising the driver HAL, which driver |
| * authors implement, are not intended to be called by application developers. |
| */ |
| |
| /* |
| * Copyright The Mbed TLS Contributors |
| * SPDX-License-Identifier: Apache-2.0 |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); you may |
| * not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| #ifndef PSA_CRYPTO_SE_DRIVER_H |
| #define PSA_CRYPTO_SE_DRIVER_H |
| #include "mbedtls/private_access.h" |
| |
| #include "crypto_driver_common.h" |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| /** \defgroup se_init Secure element driver initialization |
| */ |
| /**@{*/ |
| |
| /** \brief Driver context structure |
| * |
| * Driver functions receive a pointer to this structure. |
| * Each registered driver has one instance of this structure. |
| * |
| * Implementations must include the fields specified here and |
| * may include other fields. |
| */ |
| typedef struct { |
| /** A read-only pointer to the driver's persistent data. |
| * |
| * Drivers typically use this persistent data to keep track of |
| * which slot numbers are available. This is only a guideline: |
| * drivers may use the persistent data for any purpose, keeping |
| * in mind the restrictions on when the persistent data is saved |
| * to storage: the persistent data is only saved after calling |
| * certain functions that receive a writable pointer to the |
| * persistent data. |
| * |
| * The core allocates a memory buffer for the persistent data. |
| * The pointer is guaranteed to be suitably aligned for any data type, |
| * like a pointer returned by `malloc` (but the core can use any |
| * method to allocate the buffer, not necessarily `malloc`). |
| * |
| * The size of this buffer is in the \c persistent_data_size field of |
| * this structure. |
| * |
| * Before the driver is initialized for the first time, the content of |
| * the persistent data is all-bits-zero. After a driver upgrade, if the |
| * size of the persistent data has increased, the original data is padded |
| * on the right with zeros; if the size has decreased, the original data |
| * is truncated to the new size. |
| * |
| * This pointer is to read-only data. Only a few driver functions are |
| * allowed to modify the persistent data. These functions receive a |
| * writable pointer. These functions are: |
| * - psa_drv_se_t::p_init |
| * - psa_drv_se_key_management_t::p_allocate |
| * - psa_drv_se_key_management_t::p_destroy |
| * |
| * The PSA Cryptography core saves the persistent data from one |
| * session to the next. It does this before returning from API functions |
| * that call a driver method that is allowed to modify the persistent |
| * data, specifically: |
| * - psa_crypto_init() causes a call to psa_drv_se_t::p_init, and may call |
| * psa_drv_se_key_management_t::p_destroy to complete an action |
| * that was interrupted by a power failure. |
| * - Key creation functions cause a call to |
| * psa_drv_se_key_management_t::p_allocate, and may cause a call to |
| * psa_drv_se_key_management_t::p_destroy in case an error occurs. |
| * - psa_destroy_key() causes a call to |
| * psa_drv_se_key_management_t::p_destroy. |
| */ |
| const void *const MBEDTLS_PRIVATE(persistent_data); |
| |
| /** The size of \c persistent_data in bytes. |
| * |
| * This is always equal to the value of the `persistent_data_size` field |
| * of the ::psa_drv_se_t structure when the driver is registered. |
| */ |
| const size_t MBEDTLS_PRIVATE(persistent_data_size); |
| |
| /** Driver transient data. |
| * |
| * The core initializes this value to 0 and does not read or modify it |
| * afterwards. The driver may store whatever it wants in this field. |
| */ |
| uintptr_t MBEDTLS_PRIVATE(transient_data); |
| } psa_drv_se_context_t; |
| |
| /** \brief A driver initialization function. |
| * |
| * \param[in,out] drv_context The driver context structure. |
| * \param[in,out] persistent_data A pointer to the persistent data |
| * that allows writing. |
| * \param location The location value for which this driver |
| * is registered. The driver will be invoked |
| * for all keys whose lifetime is in this |
| * location. |
| * |
| * \retval #PSA_SUCCESS |
| * The driver is operational. |
| * The core will update the persistent data in storage. |
| * \return |
| * Any other return value prevents the driver from being used in |
| * this session. |
| * The core will NOT update the persistent data in storage. |
| */ |
| typedef psa_status_t (*psa_drv_se_init_t)(psa_drv_se_context_t *drv_context, |
| void *persistent_data, |
| psa_key_location_t location); |
| |
| #if defined(__DOXYGEN_ONLY__) || !defined(MBEDTLS_PSA_CRYPTO_SE_C) |
| /* Mbed Crypto with secure element support enabled defines this type in |
| * crypto_types.h because it is also visible to applications through an |
| * implementation-specific extension. |
| * For the PSA Cryptography specification, this type is only visible |
| * via crypto_se_driver.h. */ |
| /** An internal designation of a key slot between the core part of the |
| * PSA Crypto implementation and the driver. The meaning of this value |
| * is driver-dependent. */ |
| typedef uint64_t psa_key_slot_number_t; |
| #endif /* __DOXYGEN_ONLY__ || !MBEDTLS_PSA_CRYPTO_SE_C */ |
| |
| /**@}*/ |
| |
| /** \defgroup se_mac Secure Element Message Authentication Codes |
| * Generation and authentication of Message Authentication Codes (MACs) using |
| * a secure element can be done either as a single function call (via the |
| * `psa_drv_se_mac_generate_t` or `psa_drv_se_mac_verify_t` functions), or in |
| * parts using the following sequence: |
| * - `psa_drv_se_mac_setup_t` |
| * - `psa_drv_se_mac_update_t` |
| * - `psa_drv_se_mac_update_t` |
| * - ... |
| * - `psa_drv_se_mac_finish_t` or `psa_drv_se_mac_finish_verify_t` |
| * |
| * If a previously started secure element MAC operation needs to be terminated, |
| * it should be done so by the `psa_drv_se_mac_abort_t`. Failure to do so may |
| * result in allocated resources not being freed or in other undefined |
| * behavior. |
| */ |
| /**@{*/ |
| /** \brief A function that starts a secure element MAC operation for a PSA |
| * Crypto Driver implementation |
| * |
| * \param[in,out] drv_context The driver context structure. |
| * \param[in,out] op_context A structure that will contain the |
| * hardware-specific MAC context |
| * \param[in] key_slot The slot of the key to be used for the |
| * operation |
| * \param[in] algorithm The algorithm to be used to underly the MAC |
| * operation |
| * |
| * \retval #PSA_SUCCESS |
| * Success. |
| */ |
| typedef psa_status_t (*psa_drv_se_mac_setup_t)(psa_drv_se_context_t *drv_context, |
| void *op_context, |
| psa_key_slot_number_t key_slot, |
| psa_algorithm_t algorithm); |
| |
| /** \brief A function that continues a previously started secure element MAC |
| * operation |
| * |
| * \param[in,out] op_context A hardware-specific structure for the |
| * previously-established MAC operation to be |
| * updated |
| * \param[in] p_input A buffer containing the message to be appended |
| * to the MAC operation |
| * \param[in] input_length The size in bytes of the input message buffer |
| */ |
| typedef psa_status_t (*psa_drv_se_mac_update_t)(void *op_context, |
| const uint8_t *p_input, |
| size_t input_length); |
| |
| /** \brief a function that completes a previously started secure element MAC |
| * operation by returning the resulting MAC. |
| * |
| * \param[in,out] op_context A hardware-specific structure for the |
| * previously started MAC operation to be |
| * finished |
| * \param[out] p_mac A buffer where the generated MAC will be |
| * placed |
| * \param[in] mac_size The size in bytes of the buffer that has been |
| * allocated for the `output` buffer |
| * \param[out] p_mac_length After completion, will contain the number of |
| * bytes placed in the `p_mac` buffer |
| * |
| * \retval #PSA_SUCCESS |
| * Success. |
| */ |
| typedef psa_status_t (*psa_drv_se_mac_finish_t)(void *op_context, |
| uint8_t *p_mac, |
| size_t mac_size, |
| size_t *p_mac_length); |
| |
| /** \brief A function that completes a previously started secure element MAC |
| * operation by comparing the resulting MAC against a provided value |
| * |
| * \param[in,out] op_context A hardware-specific structure for the previously |
| * started MAC operation to be fiinished |
| * \param[in] p_mac The MAC value against which the resulting MAC |
| * will be compared against |
| * \param[in] mac_length The size in bytes of the value stored in `p_mac` |
| * |
| * \retval #PSA_SUCCESS |
| * The operation completed successfully and the MACs matched each |
| * other |
| * \retval #PSA_ERROR_INVALID_SIGNATURE |
| * The operation completed successfully, but the calculated MAC did |
| * not match the provided MAC |
| */ |
| typedef psa_status_t (*psa_drv_se_mac_finish_verify_t)(void *op_context, |
| const uint8_t *p_mac, |
| size_t mac_length); |
| |
| /** \brief A function that aborts a previous started secure element MAC |
| * operation |
| * |
| * \param[in,out] op_context A hardware-specific structure for the previously |
| * started MAC operation to be aborted |
| */ |
| typedef psa_status_t (*psa_drv_se_mac_abort_t)(void *op_context); |
| |
| /** \brief A function that performs a secure element MAC operation in one |
| * command and returns the calculated MAC |
| * |
| * \param[in,out] drv_context The driver context structure. |
| * \param[in] p_input A buffer containing the message to be MACed |
| * \param[in] input_length The size in bytes of `p_input` |
| * \param[in] key_slot The slot of the key to be used |
| * \param[in] alg The algorithm to be used to underlie the MAC |
| * operation |
| * \param[out] p_mac A buffer where the generated MAC will be |
| * placed |
| * \param[in] mac_size The size in bytes of the `p_mac` buffer |
| * \param[out] p_mac_length After completion, will contain the number of |
| * bytes placed in the `output` buffer |
| * |
| * \retval #PSA_SUCCESS |
| * Success. |
| */ |
| typedef psa_status_t (*psa_drv_se_mac_generate_t)(psa_drv_se_context_t *drv_context, |
| const uint8_t *p_input, |
| size_t input_length, |
| psa_key_slot_number_t key_slot, |
| psa_algorithm_t alg, |
| uint8_t *p_mac, |
| size_t mac_size, |
| size_t *p_mac_length); |
| |
| /** \brief A function that performs a secure element MAC operation in one |
| * command and compares the resulting MAC against a provided value |
| * |
| * \param[in,out] drv_context The driver context structure. |
| * \param[in] p_input A buffer containing the message to be MACed |
| * \param[in] input_length The size in bytes of `input` |
| * \param[in] key_slot The slot of the key to be used |
| * \param[in] alg The algorithm to be used to underlie the MAC |
| * operation |
| * \param[in] p_mac The MAC value against which the resulting MAC will |
| * be compared against |
| * \param[in] mac_length The size in bytes of `mac` |
| * |
| * \retval #PSA_SUCCESS |
| * The operation completed successfully and the MACs matched each |
| * other |
| * \retval #PSA_ERROR_INVALID_SIGNATURE |
| * The operation completed successfully, but the calculated MAC did |
| * not match the provided MAC |
| */ |
| typedef psa_status_t (*psa_drv_se_mac_verify_t)(psa_drv_se_context_t *drv_context, |
| const uint8_t *p_input, |
| size_t input_length, |
| psa_key_slot_number_t key_slot, |
| psa_algorithm_t alg, |
| const uint8_t *p_mac, |
| size_t mac_length); |
| |
| /** \brief A struct containing all of the function pointers needed to |
| * perform secure element MAC operations |
| * |
| * PSA Crypto API implementations should populate the table as appropriate |
| * upon startup. |
| * |
| * If one of the functions is not implemented (such as |
| * `psa_drv_se_mac_generate_t`), it should be set to NULL. |
| * |
| * Driver implementers should ensure that they implement all of the functions |
| * that make sense for their hardware, and that they provide a full solution |
| * (for example, if they support `p_setup`, they should also support |
| * `p_update` and at least one of `p_finish` or `p_finish_verify`). |
| * |
| */ |
| typedef struct { |
| /**The size in bytes of the hardware-specific secure element MAC context |
| * structure |
| */ |
| size_t MBEDTLS_PRIVATE(context_size); |
| /** Function that performs a MAC setup operation |
| */ |
| psa_drv_se_mac_setup_t MBEDTLS_PRIVATE(p_setup); |
| /** Function that performs a MAC update operation |
| */ |
| psa_drv_se_mac_update_t MBEDTLS_PRIVATE(p_update); |
| /** Function that completes a MAC operation |
| */ |
| psa_drv_se_mac_finish_t MBEDTLS_PRIVATE(p_finish); |
| /** Function that completes a MAC operation with a verify check |
| */ |
| psa_drv_se_mac_finish_verify_t MBEDTLS_PRIVATE(p_finish_verify); |
| /** Function that aborts a previoustly started MAC operation |
| */ |
| psa_drv_se_mac_abort_t MBEDTLS_PRIVATE(p_abort); |
| /** Function that performs a MAC operation in one call |
| */ |
| psa_drv_se_mac_generate_t MBEDTLS_PRIVATE(p_mac); |
| /** Function that performs a MAC and verify operation in one call |
| */ |
| psa_drv_se_mac_verify_t MBEDTLS_PRIVATE(p_mac_verify); |
| } psa_drv_se_mac_t; |
| /**@}*/ |
| |
| /** \defgroup se_cipher Secure Element Symmetric Ciphers |
| * |
| * Encryption and Decryption using secure element keys in block modes other |
| * than ECB must be done in multiple parts, using the following flow: |
| * - `psa_drv_se_cipher_setup_t` |
| * - `psa_drv_se_cipher_set_iv_t` (optional depending upon block mode) |
| * - `psa_drv_se_cipher_update_t` |
| * - `psa_drv_se_cipher_update_t` |
| * - ... |
| * - `psa_drv_se_cipher_finish_t` |
| * |
| * If a previously started secure element Cipher operation needs to be |
| * terminated, it should be done so by the `psa_drv_se_cipher_abort_t`. Failure |
| * to do so may result in allocated resources not being freed or in other |
| * undefined behavior. |
| * |
| * In situations where a PSA Cryptographic API implementation is using a block |
| * mode not-supported by the underlying hardware or driver, it can construct |
| * the block mode itself, while calling the `psa_drv_se_cipher_ecb_t` function |
| * for the cipher operations. |
| */ |
| /**@{*/ |
| |
| /** \brief A function that provides the cipher setup function for a |
| * secure element driver |
| * |
| * \param[in,out] drv_context The driver context structure. |
| * \param[in,out] op_context A structure that will contain the |
| * hardware-specific cipher context. |
| * \param[in] key_slot The slot of the key to be used for the |
| * operation |
| * \param[in] algorithm The algorithm to be used in the cipher |
| * operation |
| * \param[in] direction Indicates whether the operation is an encrypt |
| * or decrypt |
| * |
| * \retval #PSA_SUCCESS |
| * \retval #PSA_ERROR_NOT_SUPPORTED |
| */ |
| typedef psa_status_t (*psa_drv_se_cipher_setup_t)(psa_drv_se_context_t *drv_context, |
| void *op_context, |
| psa_key_slot_number_t key_slot, |
| psa_algorithm_t algorithm, |
| psa_encrypt_or_decrypt_t direction); |
| |
| /** \brief A function that sets the initialization vector (if |
| * necessary) for an secure element cipher operation |
| * |
| * Rationale: The `psa_se_cipher_*` operation in the PSA Cryptographic API has |
| * two IV functions: one to set the IV, and one to generate it internally. The |
| * generate function is not necessary for the drivers to implement as the PSA |
| * Crypto implementation can do the generation using its RNG features. |
| * |
| * \param[in,out] op_context A structure that contains the previously set up |
| * hardware-specific cipher context |
| * \param[in] p_iv A buffer containing the initialization vector |
| * \param[in] iv_length The size (in bytes) of the `p_iv` buffer |
| * |
| * \retval #PSA_SUCCESS |
| */ |
| typedef psa_status_t (*psa_drv_se_cipher_set_iv_t)(void *op_context, |
| const uint8_t *p_iv, |
| size_t iv_length); |
| |
| /** \brief A function that continues a previously started secure element cipher |
| * operation |
| * |
| * \param[in,out] op_context A hardware-specific structure for the |
| * previously started cipher operation |
| * \param[in] p_input A buffer containing the data to be |
| * encrypted/decrypted |
| * \param[in] input_size The size in bytes of the buffer pointed to |
| * by `p_input` |
| * \param[out] p_output The caller-allocated buffer where the |
| * output will be placed |
| * \param[in] output_size The allocated size in bytes of the |
| * `p_output` buffer |
| * \param[out] p_output_length After completion, will contain the number |
| * of bytes placed in the `p_output` buffer |
| * |
| * \retval #PSA_SUCCESS |
| */ |
| typedef psa_status_t (*psa_drv_se_cipher_update_t)(void *op_context, |
| const uint8_t *p_input, |
| size_t input_size, |
| uint8_t *p_output, |
| size_t output_size, |
| size_t *p_output_length); |
| |
| /** \brief A function that completes a previously started secure element cipher |
| * operation |
| * |
| * \param[in,out] op_context A hardware-specific structure for the |
| * previously started cipher operation |
| * \param[out] p_output The caller-allocated buffer where the output |
| * will be placed |
| * \param[in] output_size The allocated size in bytes of the `p_output` |
| * buffer |
| * \param[out] p_output_length After completion, will contain the number of |
| * bytes placed in the `p_output` buffer |
| * |
| * \retval #PSA_SUCCESS |
| */ |
| typedef psa_status_t (*psa_drv_se_cipher_finish_t)(void *op_context, |
| uint8_t *p_output, |
| size_t output_size, |
| size_t *p_output_length); |
| |
| /** \brief A function that aborts a previously started secure element cipher |
| * operation |
| * |
| * \param[in,out] op_context A hardware-specific structure for the |
| * previously started cipher operation |
| */ |
| typedef psa_status_t (*psa_drv_se_cipher_abort_t)(void *op_context); |
| |
| /** \brief A function that performs the ECB block mode for secure element |
| * cipher operations |
| * |
| * Note: this function should only be used with implementations that do not |
| * provide a needed higher-level operation. |
| * |
| * \param[in,out] drv_context The driver context structure. |
| * \param[in] key_slot The slot of the key to be used for the operation |
| * \param[in] algorithm The algorithm to be used in the cipher operation |
| * \param[in] direction Indicates whether the operation is an encrypt or |
| * decrypt |
| * \param[in] p_input A buffer containing the data to be |
| * encrypted/decrypted |
| * \param[in] input_size The size in bytes of the buffer pointed to by |
| * `p_input` |
| * \param[out] p_output The caller-allocated buffer where the output |
| * will be placed |
| * \param[in] output_size The allocated size in bytes of the `p_output` |
| * buffer |
| * |
| * \retval #PSA_SUCCESS |
| * \retval #PSA_ERROR_NOT_SUPPORTED |
| */ |
| typedef psa_status_t (*psa_drv_se_cipher_ecb_t)(psa_drv_se_context_t *drv_context, |
| psa_key_slot_number_t key_slot, |
| psa_algorithm_t algorithm, |
| psa_encrypt_or_decrypt_t direction, |
| const uint8_t *p_input, |
| size_t input_size, |
| uint8_t *p_output, |
| size_t output_size); |
| |
| /** |
| * \brief A struct containing all of the function pointers needed to implement |
| * cipher operations using secure elements. |
| * |
| * PSA Crypto API implementations should populate instances of the table as |
| * appropriate upon startup or at build time. |
| * |
| * If one of the functions is not implemented (such as |
| * `psa_drv_se_cipher_ecb_t`), it should be set to NULL. |
| */ |
| typedef struct { |
| /** The size in bytes of the hardware-specific secure element cipher |
| * context structure |
| */ |
| size_t MBEDTLS_PRIVATE(context_size); |
| /** Function that performs a cipher setup operation */ |
| psa_drv_se_cipher_setup_t MBEDTLS_PRIVATE(p_setup); |
| /** Function that sets a cipher IV (if necessary) */ |
| psa_drv_se_cipher_set_iv_t MBEDTLS_PRIVATE(p_set_iv); |
| /** Function that performs a cipher update operation */ |
| psa_drv_se_cipher_update_t MBEDTLS_PRIVATE(p_update); |
| /** Function that completes a cipher operation */ |
| psa_drv_se_cipher_finish_t MBEDTLS_PRIVATE(p_finish); |
| /** Function that aborts a cipher operation */ |
| psa_drv_se_cipher_abort_t MBEDTLS_PRIVATE(p_abort); |
| /** Function that performs ECB mode for a cipher operation |
| * (Danger: ECB mode should not be used directly by clients of the PSA |
| * Crypto Client API) |
| */ |
| psa_drv_se_cipher_ecb_t MBEDTLS_PRIVATE(p_ecb); |
| } psa_drv_se_cipher_t; |
| |
| /**@}*/ |
| |
| /** \defgroup se_asymmetric Secure Element Asymmetric Cryptography |
| * |
| * Since the amount of data that can (or should) be encrypted or signed using |
| * asymmetric keys is limited by the key size, asymmetric key operations using |
| * keys in a secure element must be done in single function calls. |
| */ |
| /**@{*/ |
| |
| /** |
| * \brief A function that signs a hash or short message with a private key in |
| * a secure element |
| * |
| * \param[in,out] drv_context The driver context structure. |
| * \param[in] key_slot Key slot of an asymmetric key pair |
| * \param[in] alg A signature algorithm that is compatible |
| * with the type of `key` |
| * \param[in] p_hash The hash to sign |
| * \param[in] hash_length Size of the `p_hash` buffer in bytes |
| * \param[out] p_signature Buffer where the signature is to be written |
| * \param[in] signature_size Size of the `p_signature` buffer in bytes |
| * \param[out] p_signature_length On success, the number of bytes |
| * that make up the returned signature value |
| * |
| * \retval #PSA_SUCCESS |
| */ |
| typedef psa_status_t (*psa_drv_se_asymmetric_sign_t)(psa_drv_se_context_t *drv_context, |
| psa_key_slot_number_t key_slot, |
| psa_algorithm_t alg, |
| const uint8_t *p_hash, |
| size_t hash_length, |
| uint8_t *p_signature, |
| size_t signature_size, |
| size_t *p_signature_length); |
| |
| /** |
| * \brief A function that verifies the signature a hash or short message using |
| * an asymmetric public key in a secure element |
| * |
| * \param[in,out] drv_context The driver context structure. |
| * \param[in] key_slot Key slot of a public key or an asymmetric key |
| * pair |
| * \param[in] alg A signature algorithm that is compatible with |
| * the type of `key` |
| * \param[in] p_hash The hash whose signature is to be verified |
| * \param[in] hash_length Size of the `p_hash` buffer in bytes |
| * \param[in] p_signature Buffer containing the signature to verify |
| * \param[in] signature_length Size of the `p_signature` buffer in bytes |
| * |
| * \retval #PSA_SUCCESS |
| * The signature is valid. |
| */ |
| typedef psa_status_t (*psa_drv_se_asymmetric_verify_t)(psa_drv_se_context_t *drv_context, |
| psa_key_slot_number_t key_slot, |
| psa_algorithm_t alg, |
| const uint8_t *p_hash, |
| size_t hash_length, |
| const uint8_t *p_signature, |
| size_t signature_length); |
| |
| /** |
| * \brief A function that encrypts a short message with an asymmetric public |
| * key in a secure element |
| * |
| * \param[in,out] drv_context The driver context structure. |
| * \param[in] key_slot Key slot of a public key or an asymmetric key |
| * pair |
| * \param[in] alg An asymmetric encryption algorithm that is |
| * compatible with the type of `key` |
| * \param[in] p_input The message to encrypt |
| * \param[in] input_length Size of the `p_input` buffer in bytes |
| * \param[in] p_salt A salt or label, if supported by the |
| * encryption algorithm |
| * If the algorithm does not support a |
| * salt, pass `NULL`. |
| * If the algorithm supports an optional |
| * salt and you do not want to pass a salt, |
| * pass `NULL`. |
| * For #PSA_ALG_RSA_PKCS1V15_CRYPT, no salt is |
| * supported. |
| * \param[in] salt_length Size of the `p_salt` buffer in bytes |
| * If `p_salt` is `NULL`, pass 0. |
| * \param[out] p_output Buffer where the encrypted message is to |
| * be written |
| * \param[in] output_size Size of the `p_output` buffer in bytes |
| * \param[out] p_output_length On success, the number of bytes that make up |
| * the returned output |
| * |
| * \retval #PSA_SUCCESS |
| */ |
| typedef psa_status_t (*psa_drv_se_asymmetric_encrypt_t)(psa_drv_se_context_t *drv_context, |
| psa_key_slot_number_t key_slot, |
| psa_algorithm_t alg, |
| const uint8_t *p_input, |
| size_t input_length, |
| const uint8_t *p_salt, |
| size_t salt_length, |
| uint8_t *p_output, |
| size_t output_size, |
| size_t *p_output_length); |
| |
| /** |
| * \brief A function that decrypts a short message with an asymmetric private |
| * key in a secure element. |
| * |
| * \param[in,out] drv_context The driver context structure. |
| * \param[in] key_slot Key slot of an asymmetric key pair |
| * \param[in] alg An asymmetric encryption algorithm that is |
| * compatible with the type of `key` |
| * \param[in] p_input The message to decrypt |
| * \param[in] input_length Size of the `p_input` buffer in bytes |
| * \param[in] p_salt A salt or label, if supported by the |
| * encryption algorithm |
| * If the algorithm does not support a |
| * salt, pass `NULL`. |
| * If the algorithm supports an optional |
| * salt and you do not want to pass a salt, |
| * pass `NULL`. |
| * For #PSA_ALG_RSA_PKCS1V15_CRYPT, no salt is |
| * supported. |
| * \param[in] salt_length Size of the `p_salt` buffer in bytes |
| * If `p_salt` is `NULL`, pass 0. |
| * \param[out] p_output Buffer where the decrypted message is to |
| * be written |
| * \param[in] output_size Size of the `p_output` buffer in bytes |
| * \param[out] p_output_length On success, the number of bytes |
| * that make up the returned output |
| * |
| * \retval #PSA_SUCCESS |
| */ |
| typedef psa_status_t (*psa_drv_se_asymmetric_decrypt_t)(psa_drv_se_context_t *drv_context, |
| psa_key_slot_number_t key_slot, |
| psa_algorithm_t alg, |
| const uint8_t *p_input, |
| size_t input_length, |
| const uint8_t *p_salt, |
| size_t salt_length, |
| uint8_t *p_output, |
| size_t output_size, |
| size_t *p_output_length); |
| |
| /** |
| * \brief A struct containing all of the function pointers needed to implement |
| * asymmetric cryptographic operations using secure elements. |
| * |
| * PSA Crypto API implementations should populate instances of the table as |
| * appropriate upon startup or at build time. |
| * |
| * If one of the functions is not implemented, it should be set to NULL. |
| */ |
| typedef struct { |
| /** Function that performs an asymmetric sign operation */ |
| psa_drv_se_asymmetric_sign_t MBEDTLS_PRIVATE(p_sign); |
| /** Function that performs an asymmetric verify operation */ |
| psa_drv_se_asymmetric_verify_t MBEDTLS_PRIVATE(p_verify); |
| /** Function that performs an asymmetric encrypt operation */ |
| psa_drv_se_asymmetric_encrypt_t MBEDTLS_PRIVATE(p_encrypt); |
| /** Function that performs an asymmetric decrypt operation */ |
| psa_drv_se_asymmetric_decrypt_t MBEDTLS_PRIVATE(p_decrypt); |
| } psa_drv_se_asymmetric_t; |
| |
| /**@}*/ |
| |
| /** \defgroup se_aead Secure Element Authenticated Encryption with Additional Data |
| * Authenticated Encryption with Additional Data (AEAD) operations with secure |
| * elements must be done in one function call. While this creates a burden for |
| * implementers as there must be sufficient space in memory for the entire |
| * message, it prevents decrypted data from being made available before the |
| * authentication operation is complete and the data is known to be authentic. |
| */ |
| /**@{*/ |
| |
| /** \brief A function that performs a secure element authenticated encryption |
| * operation |
| * |
| * \param[in,out] drv_context The driver context structure. |
| * \param[in] key_slot Slot containing the key to use. |
| * \param[in] algorithm The AEAD algorithm to compute |
| * (\c PSA_ALG_XXX value such that |
| * #PSA_ALG_IS_AEAD(`alg`) is true) |
| * \param[in] p_nonce Nonce or IV to use |
| * \param[in] nonce_length Size of the `p_nonce` buffer in bytes |
| * \param[in] p_additional_data Additional data that will be |
| * authenticated but not encrypted |
| * \param[in] additional_data_length Size of `p_additional_data` in bytes |
| * \param[in] p_plaintext Data that will be authenticated and |
| * encrypted |
| * \param[in] plaintext_length Size of `p_plaintext` in bytes |
| * \param[out] p_ciphertext Output buffer for the authenticated and |
| * encrypted data. The additional data is |
| * not part of this output. For algorithms |
| * where the encrypted data and the |
| * authentication tag are defined as |
| * separate outputs, the authentication |
| * tag is appended to the encrypted data. |
| * \param[in] ciphertext_size Size of the `p_ciphertext` buffer in |
| * bytes |
| * \param[out] p_ciphertext_length On success, the size of the output in |
| * the `p_ciphertext` buffer |
| * |
| * \retval #PSA_SUCCESS |
| * Success. |
| */ |
| typedef psa_status_t (*psa_drv_se_aead_encrypt_t)(psa_drv_se_context_t *drv_context, |
| psa_key_slot_number_t key_slot, |
| psa_algorithm_t algorithm, |
| const uint8_t *p_nonce, |
| size_t nonce_length, |
| const uint8_t *p_additional_data, |
| size_t additional_data_length, |
| const uint8_t *p_plaintext, |
| size_t plaintext_length, |
| uint8_t *p_ciphertext, |
| size_t ciphertext_size, |
| size_t *p_ciphertext_length); |
| |
| /** A function that peforms a secure element authenticated decryption operation |
| * |
| * \param[in,out] drv_context The driver context structure. |
| * \param[in] key_slot Slot containing the key to use |
| * \param[in] algorithm The AEAD algorithm to compute |
| * (\c PSA_ALG_XXX value such that |
| * #PSA_ALG_IS_AEAD(`alg`) is true) |
| * \param[in] p_nonce Nonce or IV to use |
| * \param[in] nonce_length Size of the `p_nonce` buffer in bytes |
| * \param[in] p_additional_data Additional data that has been |
| * authenticated but not encrypted |
| * \param[in] additional_data_length Size of `p_additional_data` in bytes |
| * \param[in] p_ciphertext Data that has been authenticated and |
| * encrypted. |
| * For algorithms where the encrypted data |
| * and the authentication tag are defined |
| * as separate inputs, the buffer must |
| * contain the encrypted data followed by |
| * the authentication tag. |
| * \param[in] ciphertext_length Size of `p_ciphertext` in bytes |
| * \param[out] p_plaintext Output buffer for the decrypted data |
| * \param[in] plaintext_size Size of the `p_plaintext` buffer in |
| * bytes |
| * \param[out] p_plaintext_length On success, the size of the output in |
| * the `p_plaintext` buffer |
| * |
| * \retval #PSA_SUCCESS |
| * Success. |
| */ |
| typedef psa_status_t (*psa_drv_se_aead_decrypt_t)(psa_drv_se_context_t *drv_context, |
| psa_key_slot_number_t key_slot, |
| psa_algorithm_t algorithm, |
| const uint8_t *p_nonce, |
| size_t nonce_length, |
| const uint8_t *p_additional_data, |
| size_t additional_data_length, |
| const uint8_t *p_ciphertext, |
| size_t ciphertext_length, |
| uint8_t *p_plaintext, |
| size_t plaintext_size, |
| size_t *p_plaintext_length); |
| |
| /** |
| * \brief A struct containing all of the function pointers needed to implement |
| * secure element Authenticated Encryption with Additional Data operations |
| * |
| * PSA Crypto API implementations should populate instances of the table as |
| * appropriate upon startup. |
| * |
| * If one of the functions is not implemented, it should be set to NULL. |
| */ |
| typedef struct { |
| /** Function that performs the AEAD encrypt operation */ |
| psa_drv_se_aead_encrypt_t MBEDTLS_PRIVATE(p_encrypt); |
| /** Function that performs the AEAD decrypt operation */ |
| psa_drv_se_aead_decrypt_t MBEDTLS_PRIVATE(p_decrypt); |
| } psa_drv_se_aead_t; |
| /**@}*/ |
| |
| /** \defgroup se_key_management Secure Element Key Management |
| * Currently, key management is limited to importing keys in the clear, |
| * destroying keys, and exporting keys in the clear. |
| * Whether a key may be exported is determined by the key policies in place |
| * on the key slot. |
| */ |
| /**@{*/ |
| |
| /** An enumeration indicating how a key is created. |
| */ |
| typedef enum |
| { |
| PSA_KEY_CREATION_IMPORT, /**< During psa_import_key() */ |
| PSA_KEY_CREATION_GENERATE, /**< During psa_generate_key() */ |
| PSA_KEY_CREATION_DERIVE, /**< During psa_key_derivation_output_key() */ |
| PSA_KEY_CREATION_COPY, /**< During psa_copy_key() */ |
| |
| #ifndef __DOXYGEN_ONLY__ |
| /** A key is being registered with mbedtls_psa_register_se_key(). |
| * |
| * The core only passes this value to |
| * psa_drv_se_key_management_t::p_validate_slot_number, not to |
| * psa_drv_se_key_management_t::p_allocate. The call to |
| * `p_validate_slot_number` is not followed by any other call to the |
| * driver: the key is considered successfully registered if the call to |
| * `p_validate_slot_number` succeeds, or if `p_validate_slot_number` is |
| * null. |
| * |
| * With this creation method, the driver must return #PSA_SUCCESS if |
| * the given attributes are compatible with the existing key in the slot, |
| * and #PSA_ERROR_DOES_NOT_EXIST if the driver can determine that there |
| * is no key with the specified slot number. |
| * |
| * This is an Mbed Crypto extension. |
| */ |
| PSA_KEY_CREATION_REGISTER, |
| #endif |
| } psa_key_creation_method_t; |
| |
| /** \brief A function that allocates a slot for a key. |
| * |
| * To create a key in a specific slot in a secure element, the core |
| * first calls this function to determine a valid slot number, |
| * then calls a function to create the key material in that slot. |
| * In nominal conditions (that is, if no error occurs), |
| * the effect of a call to a key creation function in the PSA Cryptography |
| * API with a lifetime that places the key in a secure element is the |
| * following: |
| * -# The core calls psa_drv_se_key_management_t::p_allocate |
| * (or in some implementations |
| * psa_drv_se_key_management_t::p_validate_slot_number). The driver |
| * selects (or validates) a suitable slot number given the key attributes |
| * and the state of the secure element. |
| * -# The core calls a key creation function in the driver. |
| * |
| * The key creation functions in the PSA Cryptography API are: |
| * - psa_import_key(), which causes |
| * a call to `p_allocate` with \p method = #PSA_KEY_CREATION_IMPORT |
| * then a call to psa_drv_se_key_management_t::p_import. |
| * - psa_generate_key(), which causes |
| * a call to `p_allocate` with \p method = #PSA_KEY_CREATION_GENERATE |
| * then a call to psa_drv_se_key_management_t::p_import. |
| * - psa_key_derivation_output_key(), which causes |
| * a call to `p_allocate` with \p method = #PSA_KEY_CREATION_DERIVE |
| * then a call to psa_drv_se_key_derivation_t::p_derive. |
| * - psa_copy_key(), which causes |
| * a call to `p_allocate` with \p method = #PSA_KEY_CREATION_COPY |
| * then a call to psa_drv_se_key_management_t::p_export. |
| * |
| * In case of errors, other behaviors are possible. |
| * - If the PSA Cryptography subsystem dies after the first step, |
| * for example because the device has lost power abruptly, |
| * the second step may never happen, or may happen after a reset |
| * and re-initialization. Alternatively, after a reset and |
| * re-initialization, the core may call |
| * psa_drv_se_key_management_t::p_destroy on the slot number that |
| * was allocated (or validated) instead of calling a key creation function. |
| * - If an error occurs, the core may call |
| * psa_drv_se_key_management_t::p_destroy on the slot number that |
| * was allocated (or validated) instead of calling a key creation function. |
| * |
| * Errors and system resets also have an impact on the driver's persistent |
| * data. If a reset happens before the overall key creation process is |
| * completed (before or after the second step above), it is unspecified |
| * whether the persistent data after the reset is identical to what it |
| * was before or after the call to `p_allocate` (or `p_validate_slot_number`). |
| * |
| * \param[in,out] drv_context The driver context structure. |
| * \param[in,out] persistent_data A pointer to the persistent data |
| * that allows writing. |
| * \param[in] attributes Attributes of the key. |
| * \param method The way in which the key is being created. |
| * \param[out] key_slot Slot where the key will be stored. |
| * This must be a valid slot for a key of the |
| * chosen type. It must be unoccupied. |
| * |
| * \retval #PSA_SUCCESS |
| * Success. |
| * The core will record \c *key_slot as the key slot where the key |
| * is stored and will update the persistent data in storage. |
| * \retval #PSA_ERROR_NOT_SUPPORTED |
| * \retval #PSA_ERROR_INSUFFICIENT_STORAGE |
| */ |
| typedef psa_status_t (*psa_drv_se_allocate_key_t)( |
| psa_drv_se_context_t *drv_context, |
| void *persistent_data, |
| const psa_key_attributes_t *attributes, |
| psa_key_creation_method_t method, |
| psa_key_slot_number_t *key_slot); |
| |
| /** \brief A function that determines whether a slot number is valid |
| * for a key. |
| * |
| * To create a key in a specific slot in a secure element, the core |
| * first calls this function to validate the choice of slot number, |
| * then calls a function to create the key material in that slot. |
| * See the documentation of #psa_drv_se_allocate_key_t for more details. |
| * |
| * As of the PSA Cryptography API specification version 1.0, there is no way |
| * for applications to trigger a call to this function. However some |
| * implementations offer the capability to create or declare a key in |
| * a specific slot via implementation-specific means, generally for the |
| * sake of initial device provisioning or onboarding. Such a mechanism may |
| * be added to a future version of the PSA Cryptography API specification. |
| * |
| * This function may update the driver's persistent data through |
| * \p persistent_data. The core will save the updated persistent data at the |
| * end of the key creation process. See the description of |
| * ::psa_drv_se_allocate_key_t for more information. |
| * |
| * \param[in,out] drv_context The driver context structure. |
| * \param[in,out] persistent_data A pointer to the persistent data |
| * that allows writing. |
| * \param[in] attributes Attributes of the key. |
| * \param method The way in which the key is being created. |
| * \param[in] key_slot Slot where the key is to be stored. |
| * |
| * \retval #PSA_SUCCESS |
| * The given slot number is valid for a key with the given |
| * attributes. |
| * \retval #PSA_ERROR_INVALID_ARGUMENT |
| * The given slot number is not valid for a key with the |
| * given attributes. This includes the case where the slot |
| * number is not valid at all. |
| * \retval #PSA_ERROR_ALREADY_EXISTS |
| * There is already a key with the specified slot number. |
| * Drivers may choose to return this error from the key |
| * creation function instead. |
| */ |
| typedef psa_status_t (*psa_drv_se_validate_slot_number_t)( |
| psa_drv_se_context_t *drv_context, |
| void *persistent_data, |
| const psa_key_attributes_t *attributes, |
| psa_key_creation_method_t method, |
| psa_key_slot_number_t key_slot); |
| |
| /** \brief A function that imports a key into a secure element in binary format |
| * |
| * This function can support any output from psa_export_key(). Refer to the |
| * documentation of psa_export_key() for the format for each key type. |
| * |
| * \param[in,out] drv_context The driver context structure. |
| * \param key_slot Slot where the key will be stored. |
| * This must be a valid slot for a key of the |
| * chosen type. It must be unoccupied. |
| * \param[in] attributes The key attributes, including the lifetime, |
| * the key type and the usage policy. |
| * Drivers should not access the key size stored |
| * in the attributes: it may not match the |
| * data passed in \p data. |
| * Drivers can call psa_get_key_lifetime(), |
| * psa_get_key_type(), |
| * psa_get_key_usage_flags() and |
| * psa_get_key_algorithm() to access this |
| * information. |
| * \param[in] data Buffer containing the key data. |
| * \param[in] data_length Size of the \p data buffer in bytes. |
| * \param[out] bits On success, the key size in bits. The driver |
| * must determine this value after parsing the |
| * key according to the key type. |
| * This value is not used if the function fails. |
| * |
| * \retval #PSA_SUCCESS |
| * Success. |
| */ |
| typedef psa_status_t (*psa_drv_se_import_key_t)( |
| psa_drv_se_context_t *drv_context, |
| psa_key_slot_number_t key_slot, |
| const psa_key_attributes_t *attributes, |
| const uint8_t *data, |
| size_t data_length, |
| size_t *bits); |
| |
| /** |
| * \brief A function that destroys a secure element key and restore the slot to |
| * its default state |
| * |
| * This function destroys the content of the key from a secure element. |
| * Implementations shall make a best effort to ensure that any previous content |
| * of the slot is unrecoverable. |
| * |
| * This function returns the specified slot to its default state. |
| * |
| * \param[in,out] drv_context The driver context structure. |
| * \param[in,out] persistent_data A pointer to the persistent data |
| * that allows writing. |
| * \param key_slot The key slot to erase. |
| * |
| * \retval #PSA_SUCCESS |
| * The slot's content, if any, has been erased. |
| */ |
| typedef psa_status_t (*psa_drv_se_destroy_key_t)( |
| psa_drv_se_context_t *drv_context, |
| void *persistent_data, |
| psa_key_slot_number_t key_slot); |
| |
| /** |
| * \brief A function that exports a secure element key in binary format |
| * |
| * The output of this function can be passed to psa_import_key() to |
| * create an equivalent object. |
| * |
| * If a key is created with `psa_import_key()` and then exported with |
| * this function, it is not guaranteed that the resulting data is |
| * identical: the implementation may choose a different representation |
| * of the same key if the format permits it. |
| * |
| * This function should generate output in the same format that |
| * `psa_export_key()` does. Refer to the |
| * documentation of `psa_export_key()` for the format for each key type. |
| * |
| * \param[in,out] drv_context The driver context structure. |
| * \param[in] key Slot whose content is to be exported. This must |
| * be an occupied key slot. |
| * \param[out] p_data Buffer where the key data is to be written. |
| * \param[in] data_size Size of the `p_data` buffer in bytes. |
| * \param[out] p_data_length On success, the number of bytes |
| * that make up the key data. |
| * |
| * \retval #PSA_SUCCESS |
| * \retval #PSA_ERROR_DOES_NOT_EXIST |
| * \retval #PSA_ERROR_NOT_PERMITTED |
| * \retval #PSA_ERROR_NOT_SUPPORTED |
| * \retval #PSA_ERROR_COMMUNICATION_FAILURE |
| * \retval #PSA_ERROR_HARDWARE_FAILURE |
| * \retval #PSA_ERROR_CORRUPTION_DETECTED |
| */ |
| typedef psa_status_t (*psa_drv_se_export_key_t)(psa_drv_se_context_t *drv_context, |
| psa_key_slot_number_t key, |
| uint8_t *p_data, |
| size_t data_size, |
| size_t *p_data_length); |
| |
| /** |
| * \brief A function that generates a symmetric or asymmetric key on a secure |
| * element |
| * |
| * If the key type \c type recorded in \p attributes |
| * is asymmetric (#PSA_KEY_TYPE_IS_ASYMMETRIC(\c type) = 1), |
| * the driver may export the public key at the time of generation, |
| * in the format documented for psa_export_public_key() by writing it |
| * to the \p pubkey buffer. |
| * This is optional, intended for secure elements that output the |
| * public key at generation time and that cannot export the public key |
| * later. Drivers that do not need this feature should leave |
| * \p *pubkey_length set to 0 and should |
| * implement the psa_drv_key_management_t::p_export_public function. |
| * Some implementations do not support this feature, in which case |
| * \p pubkey is \c NULL and \p pubkey_size is 0. |
| * |
| * \param[in,out] drv_context The driver context structure. |
| * \param key_slot Slot where the key will be stored. |
| * This must be a valid slot for a key of the |
| * chosen type. It must be unoccupied. |
| * \param[in] attributes The key attributes, including the lifetime, |
| * the key type and size, and the usage policy. |
| * Drivers can call psa_get_key_lifetime(), |
| * psa_get_key_type(), psa_get_key_bits(), |
| * psa_get_key_usage_flags() and |
| * psa_get_key_algorithm() to access this |
| * information. |
| * \param[out] pubkey A buffer where the driver can write the |
| * public key, when generating an asymmetric |
| * key pair. |
| * This is \c NULL when generating a symmetric |
| * key or if the core does not support |
| * exporting the public key at generation time. |
| * \param pubkey_size The size of the `pubkey` buffer in bytes. |
| * This is 0 when generating a symmetric |
| * key or if the core does not support |
| * exporting the public key at generation time. |
| * \param[out] pubkey_length On entry, this is always 0. |
| * On success, the number of bytes written to |
| * \p pubkey. If this is 0 or unchanged on return, |
| * the core will not read the \p pubkey buffer, |
| * and will instead call the driver's |
| * psa_drv_key_management_t::p_export_public |
| * function to export the public key when needed. |
| */ |
| typedef psa_status_t (*psa_drv_se_generate_key_t)( |
| psa_drv_se_context_t *drv_context, |
| psa_key_slot_number_t key_slot, |
| const psa_key_attributes_t *attributes, |
| uint8_t *pubkey, size_t pubkey_size, size_t *pubkey_length); |
| |
| /** |
| * \brief A struct containing all of the function pointers needed to for secure |
| * element key management |
| * |
| * PSA Crypto API implementations should populate instances of the table as |
| * appropriate upon startup or at build time. |
| * |
| * If one of the functions is not implemented, it should be set to NULL. |
| */ |
| typedef struct { |
| /** Function that allocates a slot for a key. */ |
| psa_drv_se_allocate_key_t MBEDTLS_PRIVATE(p_allocate); |
| /** Function that checks the validity of a slot for a key. */ |
| psa_drv_se_validate_slot_number_t MBEDTLS_PRIVATE(p_validate_slot_number); |
| /** Function that performs a key import operation */ |
| psa_drv_se_import_key_t MBEDTLS_PRIVATE(p_import); |
| /** Function that performs a generation */ |
| psa_drv_se_generate_key_t MBEDTLS_PRIVATE(p_generate); |
| /** Function that performs a key destroy operation */ |
| psa_drv_se_destroy_key_t MBEDTLS_PRIVATE(p_destroy); |
| /** Function that performs a key export operation */ |
| psa_drv_se_export_key_t MBEDTLS_PRIVATE(p_export); |
| /** Function that performs a public key export operation */ |
| psa_drv_se_export_key_t MBEDTLS_PRIVATE(p_export_public); |
| } psa_drv_se_key_management_t; |
| |
| /**@}*/ |
| |
| /** \defgroup driver_derivation Secure Element Key Derivation and Agreement |
| * Key derivation is the process of generating new key material using an |
| * existing key and additional parameters, iterating through a basic |
| * cryptographic function, such as a hash. |
| * Key agreement is a part of cryptographic protocols that allows two parties |
| * to agree on the same key value, but starting from different original key |
| * material. |
| * The flows are similar, and the PSA Crypto Driver Model uses the same functions |
| * for both of the flows. |
| * |
| * There are two different final functions for the flows, |
| * `psa_drv_se_key_derivation_derive` and `psa_drv_se_key_derivation_export`. |
| * `psa_drv_se_key_derivation_derive` is used when the key material should be |
| * placed in a slot on the hardware and not exposed to the caller. |
| * `psa_drv_se_key_derivation_export` is used when the key material should be |
| * returned to the PSA Cryptographic API implementation. |
| * |
| * Different key derivation algorithms require a different number of inputs. |
| * Instead of having an API that takes as input variable length arrays, which |
| * can be problemmatic to manage on embedded platforms, the inputs are passed |
| * to the driver via a function, `psa_drv_se_key_derivation_collateral`, that |
| * is called multiple times with different `collateral_id`s. Thus, for a key |
| * derivation algorithm that required 3 parameter inputs, the flow would look |
| * something like: |
| * ~~~~~~~~~~~~~{.c} |
| * psa_drv_se_key_derivation_setup(kdf_algorithm, source_key, dest_key_size_bytes); |
| * psa_drv_se_key_derivation_collateral(kdf_algorithm_collateral_id_0, |
| * p_collateral_0, |
| * collateral_0_size); |
| * psa_drv_se_key_derivation_collateral(kdf_algorithm_collateral_id_1, |
| * p_collateral_1, |
| * collateral_1_size); |
| * psa_drv_se_key_derivation_collateral(kdf_algorithm_collateral_id_2, |
| * p_collateral_2, |
| * collateral_2_size); |
| * psa_drv_se_key_derivation_derive(); |
| * ~~~~~~~~~~~~~ |
| * |
| * key agreement example: |
| * ~~~~~~~~~~~~~{.c} |
| * psa_drv_se_key_derivation_setup(alg, source_key. dest_key_size_bytes); |
| * psa_drv_se_key_derivation_collateral(DHE_PUBKEY, p_pubkey, pubkey_size); |
| * psa_drv_se_key_derivation_export(p_session_key, |
| * session_key_size, |
| * &session_key_length); |
| * ~~~~~~~~~~~~~ |
| */ |
| /**@{*/ |
| |
| /** \brief A function that Sets up a secure element key derivation operation by |
| * specifying the algorithm and the source key sot |
| * |
| * \param[in,out] drv_context The driver context structure. |
| * \param[in,out] op_context A hardware-specific structure containing any |
| * context information for the implementation |
| * \param[in] kdf_alg The algorithm to be used for the key derivation |
| * \param[in] source_key The key to be used as the source material for |
| * the key derivation |
| * |
| * \retval #PSA_SUCCESS |
| */ |
| typedef psa_status_t (*psa_drv_se_key_derivation_setup_t)(psa_drv_se_context_t *drv_context, |
| void *op_context, |
| psa_algorithm_t kdf_alg, |
| psa_key_slot_number_t source_key); |
| |
| /** \brief A function that provides collateral (parameters) needed for a secure |
| * element key derivation or key agreement operation |
| * |
| * Since many key derivation algorithms require multiple parameters, it is |
| * expected that this function may be called multiple times for the same |
| * operation, each with a different algorithm-specific `collateral_id` |
| * |
| * \param[in,out] op_context A hardware-specific structure containing any |
| * context information for the implementation |
| * \param[in] collateral_id An ID for the collateral being provided |
| * \param[in] p_collateral A buffer containing the collateral data |
| * \param[in] collateral_size The size in bytes of the collateral |
| * |
| * \retval #PSA_SUCCESS |
| */ |
| typedef psa_status_t (*psa_drv_se_key_derivation_collateral_t)(void *op_context, |
| uint32_t collateral_id, |
| const uint8_t *p_collateral, |
| size_t collateral_size); |
| |
| /** \brief A function that performs the final secure element key derivation |
| * step and place the generated key material in a slot |
| * |
| * \param[in,out] op_context A hardware-specific structure containing any |
| * context information for the implementation |
| * \param[in] dest_key The slot where the generated key material |
| * should be placed |
| * |
| * \retval #PSA_SUCCESS |
| */ |
| typedef psa_status_t (*psa_drv_se_key_derivation_derive_t)(void *op_context, |
| psa_key_slot_number_t dest_key); |
| |
| /** \brief A function that performs the final step of a secure element key |
| * agreement and place the generated key material in a buffer |
| * |
| * \param[out] p_output Buffer in which to place the generated key |
| * material |
| * \param[in] output_size The size in bytes of `p_output` |
| * \param[out] p_output_length Upon success, contains the number of bytes of |
| * key material placed in `p_output` |
| * |
| * \retval #PSA_SUCCESS |
| */ |
| typedef psa_status_t (*psa_drv_se_key_derivation_export_t)(void *op_context, |
| uint8_t *p_output, |
| size_t output_size, |
| size_t *p_output_length); |
| |
| /** |
| * \brief A struct containing all of the function pointers needed to for secure |
| * element key derivation and agreement |
| * |
| * PSA Crypto API implementations should populate instances of the table as |
| * appropriate upon startup. |
| * |
| * If one of the functions is not implemented, it should be set to NULL. |
| */ |
| typedef struct { |
| /** The driver-specific size of the key derivation context */ |
| size_t MBEDTLS_PRIVATE(context_size); |
| /** Function that performs a key derivation setup */ |
| psa_drv_se_key_derivation_setup_t MBEDTLS_PRIVATE(p_setup); |
| /** Function that sets key derivation collateral */ |
| psa_drv_se_key_derivation_collateral_t MBEDTLS_PRIVATE(p_collateral); |
| /** Function that performs a final key derivation step */ |
| psa_drv_se_key_derivation_derive_t MBEDTLS_PRIVATE(p_derive); |
| /** Function that perforsm a final key derivation or agreement and |
| * exports the key */ |
| psa_drv_se_key_derivation_export_t MBEDTLS_PRIVATE(p_export); |
| } psa_drv_se_key_derivation_t; |
| |
| /**@}*/ |
| |
| /** \defgroup se_registration Secure element driver registration |
| */ |
| /**@{*/ |
| |
| /** A structure containing pointers to all the entry points of a |
| * secure element driver. |
| * |
| * Future versions of this specification may add extra substructures at |
| * the end of this structure. |
| */ |
| typedef struct { |
| /** The version of the driver HAL that this driver implements. |
| * This is a protection against loading driver binaries built against |
| * a different version of this specification. |
| * Use #PSA_DRV_SE_HAL_VERSION. |
| */ |
| uint32_t MBEDTLS_PRIVATE(hal_version); |
| |
| /** The size of the driver's persistent data in bytes. |
| * |
| * This can be 0 if the driver does not need persistent data. |
| * |
| * See the documentation of psa_drv_se_context_t::persistent_data |
| * for more information about why and how a driver can use |
| * persistent data. |
| */ |
| size_t MBEDTLS_PRIVATE(persistent_data_size); |
| |
| /** The driver initialization function. |
| * |
| * This function is called once during the initialization of the |
| * PSA Cryptography subsystem, before any other function of the |
| * driver is called. If this function returns a failure status, |
| * the driver will be unusable, at least until the next system reset. |
| * |
| * If this field is \c NULL, it is equivalent to a function that does |
| * nothing and returns #PSA_SUCCESS. |
| */ |
| psa_drv_se_init_t MBEDTLS_PRIVATE(p_init); |
| |
| const psa_drv_se_key_management_t *MBEDTLS_PRIVATE(key_management); |
| const psa_drv_se_mac_t *MBEDTLS_PRIVATE(mac); |
| const psa_drv_se_cipher_t *MBEDTLS_PRIVATE(cipher); |
| const psa_drv_se_aead_t *MBEDTLS_PRIVATE(aead); |
| const psa_drv_se_asymmetric_t *MBEDTLS_PRIVATE(asymmetric); |
| const psa_drv_se_key_derivation_t *MBEDTLS_PRIVATE(derivation); |
| } psa_drv_se_t; |
| |
| /** The current version of the secure element driver HAL. |
| */ |
| /* 0.0.0 patchlevel 5 */ |
| #define PSA_DRV_SE_HAL_VERSION 0x00000005 |
| |
| /** Register an external cryptoprocessor (secure element) driver. |
| * |
| * This function is only intended to be used by driver code, not by |
| * application code. In implementations with separation between the |
| * PSA cryptography module and applications, this function should |
| * only be available to callers that run in the same memory space as |
| * the cryptography module, and should not be exposed to applications |
| * running in a different memory space. |
| * |
| * This function may be called before psa_crypto_init(). It is |
| * implementation-defined whether this function may be called |
| * after psa_crypto_init(). |
| * |
| * \note Implementations store metadata about keys including the lifetime |
| * value, which contains the driver's location indicator. Therefore, |
| * from one instantiation of the PSA Cryptography |
| * library to the next one, if there is a key in storage with a certain |
| * lifetime value, you must always register the same driver (or an |
| * updated version that communicates with the same secure element) |
| * with the same location value. |
| * |
| * \param location The location value through which this driver will |
| * be exposed to applications. |
| * This driver will be used for all keys such that |
| * `location == #PSA_KEY_LIFETIME_GET_LOCATION( lifetime )`. |
| * The value #PSA_KEY_LOCATION_LOCAL_STORAGE is reserved |
| * and may not be used for drivers. Implementations |
| * may reserve other values. |
| * \param[in] methods The method table of the driver. This structure must |
| * remain valid for as long as the cryptography |
| * module keeps running. It is typically a global |
| * constant. |
| * |
| * \return #PSA_SUCCESS |
| * The driver was successfully registered. Applications can now |
| * use \p location to access keys through the methods passed to |
| * this function. |
| * \return #PSA_ERROR_BAD_STATE |
| * This function was called after the initialization of the |
| * cryptography module, and this implementation does not support |
| * driver registration at this stage. |
| * \return #PSA_ERROR_ALREADY_EXISTS |
| * There is already a registered driver for this value of \p location. |
| * \return #PSA_ERROR_INVALID_ARGUMENT |
| * \p location is a reserved value. |
| * \return #PSA_ERROR_NOT_SUPPORTED |
| * `methods->hal_version` is not supported by this implementation. |
| * \return #PSA_ERROR_INSUFFICIENT_MEMORY |
| * \return #PSA_ERROR_NOT_PERMITTED |
| * \return #PSA_ERROR_STORAGE_FAILURE |
| * \return #PSA_ERROR_DATA_CORRUPT |
| */ |
| psa_status_t psa_register_se_driver( |
| psa_key_location_t location, |
| const psa_drv_se_t *methods); |
| |
| /**@}*/ |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif /* PSA_CRYPTO_SE_DRIVER_H */ |