/** * \file psa/crypto_extra.h * * \brief PSA cryptography module: Mbed TLS vendor extensions * * \note This file may not be included directly. Applications must * include psa/crypto.h. * * This file is reserved for vendor-specific definitions. */ /* * Copyright (C) 2018, ARM Limited, All Rights Reserved * 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. * * This file is part of mbed TLS (https://tls.mbed.org) */ #ifndef PSA_CRYPTO_EXTRA_H #define PSA_CRYPTO_EXTRA_H #include "mbedtls/platform_util.h" #ifdef __cplusplus extern "C" { #endif /* UID for secure storage seed */ #define PSA_CRYPTO_ITS_RANDOM_SEED_UID 0xFFFFFF52 /* * Deprecated PSA Crypto error code definitions */ #if !defined(MBEDTLS_DEPRECATED_REMOVED) #define PSA_ERROR_UNKNOWN_ERROR \ MBEDTLS_DEPRECATED_NUMERIC_CONSTANT( PSA_ERROR_GENERIC_ERROR ) #endif #if !defined(MBEDTLS_DEPRECATED_REMOVED) #define PSA_ERROR_OCCUPIED_SLOT \ MBEDTLS_DEPRECATED_NUMERIC_CONSTANT( PSA_ERROR_ALREADY_EXISTS ) #endif #if !defined(MBEDTLS_DEPRECATED_REMOVED) #define PSA_ERROR_EMPTY_SLOT \ MBEDTLS_DEPRECATED_NUMERIC_CONSTANT( PSA_ERROR_DOES_NOT_EXIST ) #endif #if !defined(MBEDTLS_DEPRECATED_REMOVED) #define PSA_ERROR_INSUFFICIENT_CAPACITY \ MBEDTLS_DEPRECATED_NUMERIC_CONSTANT( PSA_ERROR_INSUFFICIENT_DATA ) #endif /** * \brief Library deinitialization. * * This function clears all data associated with the PSA layer, * including the whole key store. * * This is an Mbed TLS extension. */ void mbedtls_psa_crypto_free( void ); /** * \brief Inject an initial entropy seed for the random generator into * secure storage. * * This function injects data to be used as a seed for the random generator * used by the PSA Crypto implementation. On devices that lack a trusted * entropy source (preferably a hardware random number generator), * the Mbed PSA Crypto implementation uses this value to seed its * random generator. * * On devices without a trusted entropy source, this function must be * called exactly once in the lifetime of the device. On devices with * a trusted entropy source, calling this function is optional. * In all cases, this function may only be called before calling any * other function in the PSA Crypto API, including psa_crypto_init(). * * When this function returns successfully, it populates a file in * persistent storage. Once the file has been created, this function * can no longer succeed. * * If any error occurs, this function does not change the system state. * You can call this function again after correcting the reason for the * error if possible. * * \warning This function **can** fail! Callers MUST check the return status. * * \warning If you use this function, you should use it as part of a * factory provisioning process. The value of the injected seed * is critical to the security of the device. It must be * *secret*, *unpredictable* and (statistically) *unique per device*. * You should be generate it randomly using a cryptographically * secure random generator seeded from trusted entropy sources. * You should transmit it securely to the device and ensure * that its value is not leaked or stored anywhere beyond the * needs of transmitting it from the point of generation to * the call of this function, and erase all copies of the value * once this function returns. * * This is an Mbed TLS extension. * * \note This function is only available on the following platforms: * * If the compile-time option MBEDTLS_PSA_INJECT_ENTROPY is enabled. * Note that you must provide compatible implementations of * mbedtls_nv_seed_read and mbedtls_nv_seed_write. * * In a client-server integration of PSA Cryptography, on the client side, * if the server supports this feature. * \param[in] seed Buffer containing the seed value to inject. * \param[in] seed_size Size of the \p seed buffer. * The size of the seed in bytes must be greater * or equal to both #MBEDTLS_ENTROPY_MIN_PLATFORM * and #MBEDTLS_ENTROPY_BLOCK_SIZE. * It must be less or equal to * #MBEDTLS_ENTROPY_MAX_SEED_SIZE. * * \retval #PSA_SUCCESS * The seed value was injected successfully. The random generator * of the PSA Crypto implementation is now ready for use. * You may now call psa_crypto_init() and use the PSA Crypto * implementation. * \retval #PSA_ERROR_INVALID_ARGUMENT * \p seed_size is out of range. * \retval #PSA_ERROR_STORAGE_FAILURE * There was a failure reading or writing from storage. * \retval #PSA_ERROR_NOT_PERMITTED * The library has already been initialized. It is no longer * possible to call this function. */ psa_status_t mbedtls_psa_inject_entropy(const unsigned char *seed, size_t seed_size); /** Set up a key derivation operation. * * FIMXE This function is no longer part of the official API. Its prototype * is only kept around for the sake of tests that haven't been updated yet. * * A key derivation algorithm takes three inputs: a secret input \p handle and * two non-secret inputs \p label and p salt. * The result of this function is a byte generator which can * be used to produce keys and other cryptographic material. * * The role of \p label and \p salt is as follows: * - For HKDF (#PSA_ALG_HKDF), \p salt is the salt used in the "extract" step * and \p label is the info string used in the "expand" step. * * \param[in,out] operation The key derivation object to set up. It must have * been initialized as per the documentation for * #psa_key_derivation_operation_t and not yet in use. * \param handle Handle to the secret key. * \param alg The key derivation algorithm to compute * (\c PSA_ALG_XXX value such that * #PSA_ALG_IS_KEY_DERIVATION(\p alg) is true). * \param[in] salt Salt to use. * \param salt_length Size of the \p salt buffer in bytes. * \param[in] label Label to use. * \param label_length Size of the \p label buffer in bytes. * \param capacity The maximum number of bytes that the * operation will be able to provide. * * \retval #PSA_SUCCESS * Success. * \retval #PSA_ERROR_INVALID_HANDLE * \retval #PSA_ERROR_EMPTY_SLOT * \retval #PSA_ERROR_NOT_PERMITTED * \retval #PSA_ERROR_INVALID_ARGUMENT * \c key is not compatible with \c alg, * or \p capacity is too large for the specified algorithm and key. * \retval #PSA_ERROR_NOT_SUPPORTED * \c alg is not supported or is not a key derivation algorithm. * \retval #PSA_ERROR_INSUFFICIENT_MEMORY * \retval #PSA_ERROR_COMMUNICATION_FAILURE * \retval #PSA_ERROR_HARDWARE_FAILURE * \retval #PSA_ERROR_TAMPERING_DETECTED * \retval #PSA_ERROR_BAD_STATE * The library has not been previously initialized by psa_crypto_init(). * It is implementation-dependent whether a failure to initialize * results in this error code. */ psa_status_t psa_key_derivation(psa_key_derivation_operation_t *operation, psa_key_handle_t handle, psa_algorithm_t alg, const uint8_t *salt, size_t salt_length, const uint8_t *label, size_t label_length, size_t capacity); /* FIXME Deprecated. Remove this as soon as all the tests are updated. */ #define PSA_ALG_SELECT_RAW ((psa_algorithm_t)0x31000001) /** \defgroup policy Key policies * @{ * * The functions in this section are legacy interfaces where the properties * of a key object are set after allocating a handle, in constrast with the * preferred interface where key objects are created atomically from * a structure that represents the properties. */ /** \def PSA_KEY_POLICY_INIT * * This macro returns a suitable initializer for a key policy object of type * #psa_key_policy_t. */ #ifdef __DOXYGEN_ONLY__ /* This is an example definition for documentation purposes. * Implementations should define a suitable value in `crypto_struct.h`. */ #define PSA_KEY_POLICY_INIT {0} #endif /** Return an initial value for a key policy that forbids all usage of the key. */ static psa_key_policy_t psa_key_policy_init(void); /** \brief Set the standard fields of a policy structure. * * Note that this function does not make any consistency check of the * parameters. The values are only checked when applying the policy to * a key slot with psa_set_key_policy(). * * \param[in,out] policy The key policy to modify. It must have been * initialized as per the documentation for * #psa_key_policy_t. * \param usage The permitted uses for the key. * \param alg The algorithm that the key may be used for. */ void psa_key_policy_set_usage(psa_key_policy_t *policy, psa_key_usage_t usage, psa_algorithm_t alg); /** \brief Retrieve the usage field of a policy structure. * * \param[in] policy The policy object to query. * * \return The permitted uses for a key with this policy. */ psa_key_usage_t psa_key_policy_get_usage(const psa_key_policy_t *policy); /** \brief Retrieve the algorithm field of a policy structure. * * \param[in] policy The policy object to query. * * \return The permitted algorithm for a key with this policy. */ psa_algorithm_t psa_key_policy_get_algorithm(const psa_key_policy_t *policy); /** \brief Set the usage policy on a key slot. * * This function must be called on an empty key slot, before importing, * generating or creating a key in the slot. Changing the policy of an * existing key is not permitted. * * Implementations may set restrictions on supported key policies * depending on the key type and the key slot. * * \param handle Handle to the key whose policy is to be changed. * \param[in] policy The policy object to query. * * \retval #PSA_SUCCESS * Success. * If the key is persistent, it is implementation-defined whether * the policy has been saved to persistent storage. Implementations * may defer saving the policy until the key material is created. * \retval #PSA_ERROR_INVALID_HANDLE * \retval #PSA_ERROR_ALREADY_EXISTS * \retval #PSA_ERROR_NOT_SUPPORTED * \retval #PSA_ERROR_INVALID_ARGUMENT * \retval #PSA_ERROR_COMMUNICATION_FAILURE * \retval #PSA_ERROR_HARDWARE_FAILURE * \retval #PSA_ERROR_TAMPERING_DETECTED * \retval #PSA_ERROR_BAD_STATE * The library has not been previously initialized by psa_crypto_init(). * It is implementation-dependent whether a failure to initialize * results in this error code. */ psa_status_t psa_set_key_policy(psa_key_handle_t handle, const psa_key_policy_t *policy); /** \brief Get the usage policy for a key slot. * * \param handle Handle to the key slot whose policy is being queried. * \param[out] policy On success, the key's policy. * * \retval #PSA_SUCCESS * \retval #PSA_ERROR_INVALID_HANDLE * \retval #PSA_ERROR_COMMUNICATION_FAILURE * \retval #PSA_ERROR_HARDWARE_FAILURE * \retval #PSA_ERROR_TAMPERING_DETECTED * \retval #PSA_ERROR_BAD_STATE * The library has not been previously initialized by psa_crypto_init(). * It is implementation-dependent whether a failure to initialize * results in this error code. */ psa_status_t psa_get_key_policy(psa_key_handle_t handle, psa_key_policy_t *policy); /**@}*/ /** \defgroup to_handle Key creation to allocated handle * @{ * * The functions in this section are legacy interfaces where the properties * of a key object are set after allocating a handle, in constrast with the * preferred interface where key objects are created atomically from * a structure that represents the properties. */ /** Create a new persistent key slot. * * Create a new persistent key slot and return a handle to it. The handle * remains valid until the application calls psa_close_key() or terminates. * The application can open the key again with psa_open_key() until it * removes the key by calling psa_destroy_key(). * * \param lifetime The lifetime of the key. This designates a storage * area where the key material is stored. This must not * be #PSA_KEY_LIFETIME_VOLATILE. * \param id The persistent identifier of the key. * \param[out] handle On success, a handle to the newly created key slot. * When key material is later created in this key slot, * it will be saved to the specified persistent location. * * \retval #PSA_SUCCESS * Success. The application can now use the value of `*handle` * to access the newly allocated key slot. * \retval #PSA_ERROR_INSUFFICIENT_MEMORY * \retval #PSA_ERROR_INSUFFICIENT_STORAGE * \retval #PSA_ERROR_ALREADY_EXISTS * There is already a key with the identifier \p id in the storage * area designated by \p lifetime. * \retval #PSA_ERROR_INVALID_ARGUMENT * \p lifetime is invalid, for example #PSA_KEY_LIFETIME_VOLATILE. * \retval #PSA_ERROR_INVALID_ARGUMENT * \p id is invalid for the specified lifetime. * \retval #PSA_ERROR_NOT_SUPPORTED * \p lifetime is not supported. * \retval #PSA_ERROR_NOT_PERMITTED * \p lifetime is valid, but the application does not have the * permission to create a key there. */ psa_status_t psa_create_key(psa_key_lifetime_t lifetime, psa_key_id_t id, psa_key_handle_t *handle); /** Allocate a key slot for a transient key, i.e. a key which is only stored * in volatile memory. * * The allocated key slot and its handle remain valid until the * application calls psa_close_key() or psa_destroy_key() or until the * application terminates. * * \param[out] handle On success, a handle to a volatile key slot. * * \retval #PSA_SUCCESS * Success. The application can now use the value of `*handle` * to access the newly allocated key slot. * \retval #PSA_ERROR_INSUFFICIENT_MEMORY * There was not enough memory, or the maximum number of key slots * has been reached. */ psa_status_t psa_allocate_key(psa_key_handle_t *handle); /** * \brief Get basic metadata about a key. * * \param handle Handle to the key slot to query. * \param[out] type On success, the key type (a \c PSA_KEY_TYPE_XXX value). * This may be a null pointer, in which case the key type * is not written. * \param[out] bits On success, the key size in bits. * This may be a null pointer, in which case the key size * is not written. * * \retval #PSA_SUCCESS * \retval #PSA_ERROR_INVALID_HANDLE * \retval #PSA_ERROR_DOES_NOT_EXIST * The handle is to a key slot which does not contain key material yet. * \retval #PSA_ERROR_COMMUNICATION_FAILURE * \retval #PSA_ERROR_HARDWARE_FAILURE * \retval #PSA_ERROR_TAMPERING_DETECTED * \retval #PSA_ERROR_BAD_STATE * The library has not been previously initialized by psa_crypto_init(). * It is implementation-dependent whether a failure to initialize * results in this error code. */ psa_status_t psa_get_key_information(psa_key_handle_t handle, psa_key_type_t *type, size_t *bits); /** \brief Retrieve the lifetime of an open key. * * \param handle Handle to query. * \param[out] lifetime On success, the lifetime value. * * \retval #PSA_SUCCESS * Success. * \retval #PSA_ERROR_INVALID_HANDLE * \retval #PSA_ERROR_COMMUNICATION_FAILURE * \retval #PSA_ERROR_HARDWARE_FAILURE * \retval #PSA_ERROR_TAMPERING_DETECTED * \retval #PSA_ERROR_BAD_STATE * The library has not been previously initialized by psa_crypto_init(). * It is implementation-dependent whether a failure to initialize * results in this error code. */ psa_status_t psa_get_key_lifetime_from_handle(psa_key_handle_t handle, psa_key_lifetime_t *lifetime); psa_status_t psa_import_key_to_handle(psa_key_handle_t handle, psa_key_type_t type, const uint8_t *data, size_t data_length); psa_status_t psa_copy_key_to_handle(psa_key_handle_t source_handle, psa_key_handle_t target_handle, const psa_key_policy_t *constraint); psa_status_t psa_generate_derived_key_to_handle(psa_key_handle_t handle, psa_key_type_t type, size_t bits, psa_key_derivation_operation_t *operation); psa_status_t psa_generate_random_key_to_handle(psa_key_handle_t handle, psa_key_type_t type, size_t bits, const void *extra, size_t extra_size); /**@}*/ #ifdef __cplusplus } #endif #endif /* PSA_CRYPTO_EXTRA_H */