1 /* Copyright (c) 2024 Nordic Semiconductor 2 * SPDX-License-Identifier: Apache-2.0 3 */ 4 #ifndef SECURE_STORAGE_ITS_TRANSFORM_H 5 #define SECURE_STORAGE_ITS_TRANSFORM_H 6 7 /** @file zephyr/secure_storage/its/transform.h The secure storage ITS transform module. 8 * 9 * The functions declared in this header implement the ITS transform module. 10 * They are meant to be called only by the ITS implementation. 11 * This header may be included when providing a custom implementation of the 12 * ITS transform module (@kconfig{CONFIG_SECURE_STORAGE_ITS_TRANSFORM_IMPLEMENTATION_CUSTOM}). 13 */ 14 #include <zephyr/secure_storage/its/common.h> 15 16 /** The maximum size, in bytes, of an entry's data after it has been transformed for storage. */ 17 enum { SECURE_STORAGE_ITS_TRANSFORM_MAX_STORED_DATA_SIZE 18 = CONFIG_SECURE_STORAGE_ITS_MAX_DATA_SIZE 19 + sizeof(secure_storage_packed_create_flags_t) 20 + CONFIG_SECURE_STORAGE_ITS_TRANSFORM_OUTPUT_OVERHEAD }; 21 22 #define SECURE_STORAGE_ITS_TRANSFORM_DATA_SIZE(stored_data_len) \ 23 (stored_data_len - (SECURE_STORAGE_ITS_TRANSFORM_MAX_STORED_DATA_SIZE \ 24 - CONFIG_SECURE_STORAGE_ITS_MAX_DATA_SIZE)) 25 26 /** @brief Transforms the data of an ITS entry for storage. 27 * 28 * @param[in] uid The entry's UID. 29 * @param[in] data_len The number of bytes in `data`. 30 * @param[in] data The data to transform for storage. 31 * @param[in] create_flags The entry's create flags. It must contain only valid 32 * `PSA_STORAGE_FLAG_*` values. It gets stored as part of `stored_data`. 33 * @param[out] stored_data The buffer to which the transformed data is written. 34 * @param[out] stored_data_len On success, the number of bytes written to `stored_data`. 35 * 36 * @return `PSA_SUCCESS` on success, anything else on failure. 37 */ 38 psa_status_t secure_storage_its_transform_to_store( 39 secure_storage_its_uid_t uid, size_t data_len, const void *data, 40 secure_storage_packed_create_flags_t create_flags, 41 uint8_t stored_data[static SECURE_STORAGE_ITS_TRANSFORM_MAX_STORED_DATA_SIZE], 42 size_t *stored_data_len); 43 44 /** @brief Transforms and validates the stored data of an ITS entry for use. 45 * 46 * @param[in] uid The entry's UID. 47 * @param[in] stored_data_len The number of bytes in `stored_data`. 48 * @param[in] stored_data The stored data to transform for use. 49 * @param[in] data_size The size of `data` in bytes. 50 * @param[out] data The buffer to which the transformed data is written. 51 * @param[out] data_len On success, the number of bytes written to `stored_data`. 52 * @param[out] create_flags On success, the entry's create flags. 53 * 54 * @return `PSA_SUCCESS` on success, anything else on failure. 55 */ 56 psa_status_t secure_storage_its_transform_from_store( 57 secure_storage_its_uid_t uid, size_t stored_data_len, 58 const uint8_t stored_data[static SECURE_STORAGE_ITS_TRANSFORM_MAX_STORED_DATA_SIZE], 59 size_t data_size, void *data, size_t *data_len, 60 psa_storage_create_flags_t *create_flags); 61 62 #endif 63
