esp-idf/components/nvs_flash/include/nvs_flash.h

324 lines
12 KiB
C

/*
* SPDX-FileCopyrightText: 2015-2023 Espressif Systems (Shanghai) CO LTD
*
* SPDX-License-Identifier: Apache-2.0
*/
#ifndef nvs_flash_h
#define nvs_flash_h
#ifdef __cplusplus
extern "C" {
#endif
#include "nvs.h"
#include "esp_partition.h"
#define NVS_KEY_SIZE 32 // AES-256
/**
* @brief Key for encryption and decryption
*/
typedef struct {
uint8_t eky[NVS_KEY_SIZE]; /*!< XTS encryption and decryption key*/
uint8_t tky[NVS_KEY_SIZE]; /*!< XTS tweak key */
} nvs_sec_cfg_t;
/**
* @brief Callback function prototype for generating the NVS encryption keys
*/
typedef esp_err_t (*nvs_flash_generate_keys_t) (const void *scheme_data, nvs_sec_cfg_t* cfg);
/**
* @brief Callback function prototype for reading the NVS encryption keys
*/
typedef esp_err_t (*nvs_flash_read_cfg_t) (const void *scheme_data, nvs_sec_cfg_t* cfg);
/**
* @brief NVS encryption: Security scheme configuration structure
*/
typedef struct
{
int scheme_id; /*!< Security Scheme ID (E.g. HMAC) */
void *scheme_data; /*!< Scheme-specific data (E.g. eFuse block for HMAC-based key generation) */
nvs_flash_generate_keys_t nvs_flash_key_gen; /*!< Callback for the nvs_flash_key_gen implementation */
nvs_flash_read_cfg_t nvs_flash_read_cfg; /*!< Callback for the nvs_flash_read_keys implementation */
} nvs_sec_scheme_t;
/**
* @brief Initialize the default NVS partition.
*
* This API initialises the default NVS partition. The default NVS partition
* is the one that is labeled "nvs" in the partition table.
*
* When "NVS_ENCRYPTION" is enabled in the menuconfig, this API enables
* the NVS encryption for the default NVS partition as follows
* 1. Read security configurations from the first NVS key
* partition listed in the partition table. (NVS key partition is
* any "data" type partition which has the subtype value set to "nvs_keys")
* 2. If the NVS key partition obtained in the previous step is empty,
* generate and store new keys in that NVS key partition.
* 3. Internally call "nvs_flash_secure_init()" with
* the security configurations obtained/generated in the previous steps.
*
* Post initialization NVS read/write APIs
* remain the same irrespective of NVS encryption.
*
* @return
* - ESP_OK if storage was successfully initialized.
* - ESP_ERR_NVS_NO_FREE_PAGES if the NVS storage contains no empty pages
* (which may happen if NVS partition was truncated)
* - ESP_ERR_NOT_FOUND if no partition with label "nvs" is found in the partition table
* - ESP_ERR_NO_MEM in case memory could not be allocated for the internal structures
* - one of the error codes from the underlying flash storage driver
* - error codes from nvs_flash_read_security_cfg API (when "NVS_ENCRYPTION" is enabled).
* - error codes from nvs_flash_generate_keys API (when "NVS_ENCRYPTION" is enabled).
* - error codes from nvs_flash_secure_init_partition API (when "NVS_ENCRYPTION" is enabled) .
*/
esp_err_t nvs_flash_init(void);
/**
* @brief Initialize NVS flash storage for the specified partition.
*
* @param[in] partition_label Label of the partition. Must be no longer than 16 characters.
*
* @return
* - ESP_OK if storage was successfully initialized.
* - ESP_ERR_NVS_NO_FREE_PAGES if the NVS storage contains no empty pages
* (which may happen if NVS partition was truncated)
* - ESP_ERR_NOT_FOUND if specified partition is not found in the partition table
* - ESP_ERR_NO_MEM in case memory could not be allocated for the internal structures
* - one of the error codes from the underlying flash storage driver
*/
esp_err_t nvs_flash_init_partition(const char *partition_label);
/**
* @brief Initialize NVS flash storage for the partition specified by partition pointer.
*
* @param[in] partition pointer to a partition obtained by the ESP partition API.
*
* @return
* - ESP_OK if storage was successfully initialized
* - ESP_ERR_NVS_NO_FREE_PAGES if the NVS storage contains no empty pages
* (which may happen if NVS partition was truncated)
* - ESP_ERR_INVALID_ARG in case partition is NULL
* - ESP_ERR_NO_MEM in case memory could not be allocated for the internal structures
* - one of the error codes from the underlying flash storage driver
*/
esp_err_t nvs_flash_init_partition_ptr(const esp_partition_t *partition);
/**
* @brief Deinitialize NVS storage for the default NVS partition
*
* Default NVS partition is the partition with "nvs" label in the partition table.
*
* @return
* - ESP_OK on success (storage was deinitialized)
* - ESP_ERR_NVS_NOT_INITIALIZED if the storage was not initialized prior to this call
*/
esp_err_t nvs_flash_deinit(void);
/**
* @brief Deinitialize NVS storage for the given NVS partition
*
* @param[in] partition_label Label of the partition
*
* @return
* - ESP_OK on success
* - ESP_ERR_NVS_NOT_INITIALIZED if the storage for given partition was not
* initialized prior to this call
*/
esp_err_t nvs_flash_deinit_partition(const char* partition_label);
/**
* @brief Erase the default NVS partition
*
* Erases all contents of the default NVS partition (one with label "nvs").
*
* @note If the partition is initialized, this function first de-initializes it. Afterwards, the partition has to
* be initialized again to be used.
*
* @return
* - ESP_OK on success
* - ESP_ERR_NOT_FOUND if there is no NVS partition labeled "nvs" in the
* partition table
* - different error in case de-initialization fails (shouldn't happen)
*/
esp_err_t nvs_flash_erase(void);
/**
* @brief Erase specified NVS partition
*
* Erase all content of a specified NVS partition
*
* @note If the partition is initialized, this function first de-initializes it. Afterwards, the partition has to
* be initialized again to be used.
*
* @param[in] part_name Name (label) of the partition which should be erased
*
* @return
* - ESP_OK on success
* - ESP_ERR_NOT_FOUND if there is no NVS partition with the specified name
* in the partition table
* - different error in case de-initialization fails (shouldn't happen)
*/
esp_err_t nvs_flash_erase_partition(const char *part_name);
/**
* @brief Erase custom partition.
*
* Erase all content of specified custom partition.
*
* @note
* If the partition is initialized, this function first de-initializes it.
* Afterwards, the partition has to be initialized again to be used.
*
* @param[in] partition pointer to a partition obtained by the ESP partition API.
*
* @return
* - ESP_OK on success
* - ESP_ERR_NOT_FOUND if there is no partition with the specified
* parameters in the partition table
* - ESP_ERR_INVALID_ARG in case partition is NULL
* - one of the error codes from the underlying flash storage driver
*/
esp_err_t nvs_flash_erase_partition_ptr(const esp_partition_t *partition);
/**
* @brief Initialize the default NVS partition.
*
* This API initialises the default NVS partition. The default NVS partition
* is the one that is labeled "nvs" in the partition table.
*
* @param[in] cfg Security configuration (keys) to be used for NVS encryption/decryption.
* If cfg is NULL, no encryption is used.
*
* @return
* - ESP_OK if storage has been initialized successfully.
* - ESP_ERR_NVS_NO_FREE_PAGES if the NVS storage contains no empty pages
* (which may happen if NVS partition was truncated)
* - ESP_ERR_NOT_FOUND if no partition with label "nvs" is found in the partition table
* - ESP_ERR_NO_MEM in case memory could not be allocated for the internal structures
* - one of the error codes from the underlying flash storage driver
*/
esp_err_t nvs_flash_secure_init(nvs_sec_cfg_t* cfg);
/**
* @brief Initialize NVS flash storage for the specified partition.
*
* @param[in] partition_label Label of the partition. Note that internally, a reference to
* passed value is kept and it should be accessible for future operations
*
* @param[in] cfg Security configuration (keys) to be used for NVS encryption/decryption.
* If cfg is null, no encryption/decryption is used.
* @return
* - ESP_OK if storage has been initialized successfully.
* - ESP_ERR_NVS_NO_FREE_PAGES if the NVS storage contains no empty pages
* (which may happen if NVS partition was truncated)
* - ESP_ERR_NOT_FOUND if specified partition is not found in the partition table
* - ESP_ERR_NO_MEM in case memory could not be allocated for the internal structures
* - one of the error codes from the underlying flash storage driver
*/
esp_err_t nvs_flash_secure_init_partition(const char *partition_label, nvs_sec_cfg_t* cfg);
/**
* @brief Generate and store NVS keys in the provided esp partition
*
* @param[in] partition Pointer to partition structure obtained using
* esp_partition_find_first or esp_partition_get.
* Must be non-NULL.
* @param[out] cfg Pointer to nvs security configuration structure.
* Pointer must be non-NULL.
* Generated keys will be populated in this structure.
*
*
* @return
* - ESP_OK, if cfg was read successfully;
* - ESP_ERR_INVALID_ARG, if partition or cfg is NULL;
* - or error codes from esp_partition_write/erase APIs.
*/
esp_err_t nvs_flash_generate_keys(const esp_partition_t* partition, nvs_sec_cfg_t* cfg);
/**
* @brief Read NVS security configuration from a partition.
*
* @param[in] partition Pointer to partition structure obtained using
* esp_partition_find_first or esp_partition_get.
* Must be non-NULL.
* @param[out] cfg Pointer to nvs security configuration structure.
* Pointer must be non-NULL.
*
* @note Provided partition is assumed to be marked 'encrypted'.
*
* @return
* - ESP_OK, if cfg was read successfully;
* - ESP_ERR_INVALID_ARG, if partition or cfg is NULL
* - ESP_ERR_NVS_KEYS_NOT_INITIALIZED, if the partition is not yet written with keys.
* - ESP_ERR_NVS_CORRUPT_KEY_PART, if the partition containing keys is found to be corrupt
* - or error codes from esp_partition_read API.
*/
esp_err_t nvs_flash_read_security_cfg(const esp_partition_t* partition, nvs_sec_cfg_t* cfg);
/**
* @brief Registers the given security scheme for NVS encryption
* The scheme registered with sec_scheme_id by this API be used as
* the default security scheme for the "nvs" partition.
* Users will have to call this API explicitly in their application.
*
* @param[in] scheme_cfg Pointer to the security scheme configuration structure
* that the user (or the nvs_key_provider) wants to register.
*
* @return
* - ESP_OK, if security scheme registration succeeds;
* - ESP_ERR_INVALID_ARG, if scheme_cfg is NULL;
* - ESP_FAIL, if security scheme registration fails
*/
esp_err_t nvs_flash_register_security_scheme(nvs_sec_scheme_t *scheme_cfg);
/**
* @brief Fetch the configuration structure for the default active
* security scheme for NVS encryption
*
* @return Pointer to the default active security scheme configuration
* (NULL if no scheme is registered yet i.e. active)
*/
nvs_sec_scheme_t *nvs_flash_get_default_security_scheme(void);
/**
* @brief Generate (and store) the NVS keys using the specified key-protection scheme
*
* @param[in] scheme_cfg Security scheme specific configuration
*
* @param[out] cfg Security configuration (encryption keys)
*
* @return
* - ESP_OK, if cfg was populated successfully with generated encryption keys;
* - ESP_ERR_INVALID_ARG, if scheme_cfg or cfg is NULL;
* - ESP_FAIL, if the key generation process fails
*/
esp_err_t nvs_flash_generate_keys_v2(nvs_sec_scheme_t *scheme_cfg, nvs_sec_cfg_t* cfg);
/**
* @brief Read NVS security configuration set by the specified security scheme
*
* @param[in] scheme_cfg Security scheme specific configuration
*
* @param[out] cfg Security configuration (encryption keys)
*
* @return
* - ESP_OK, if cfg was read successfully;
* - ESP_ERR_INVALID_ARG, if scheme_cfg or cfg is NULL;
* - ESP_FAIL, if the key reading process fails
*/
esp_err_t nvs_flash_read_security_cfg_v2(nvs_sec_scheme_t *scheme_cfg, nvs_sec_cfg_t* cfg);
#ifdef __cplusplus
}
#endif
#endif /* nvs_flash_h */