AESCTRDRBGXX.h

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/*!****************************************************************************
 *  @file       AESCTRDRBGXX.h
 *
 *  @brief      Generic AESCTRDRBG implementation based on the AESCTR driver
 *
 *  @warning     This is a beta API. It may change in future releases.
 *
 *  This file should only be included in the board file to fill the AESCTR_config
 *  struct.
 *
 *  # Use of AESCTR #
 *  This implementation uses the AESCTR driver to generate the random bitstream
 *  required to mutate the internal AESCTRDRBG state and provide random output
 *  bits. The driver will open an instance of the AESCTR driver based on the index
 *  specified in #AESCTRDRBGXX_HWAttrs:aesctrIndex. Mutual exclusion and hardware
 *  access are all handled by the AESCTR driver instance.
 *
 *  # Implementation Limitations
 *  - Only plaintext CryptoKeys are supported by this implementation.
 *
 *  # Runtime Parameter Validation #
 *  The driver implementation does not perform runtime checks for most input parameters.
 *  Only values that are likely to have a stochastic element to them are checked (such
 *  as whether a driver is already open). Higher input paramter validation coverage is
 *  achieved by turning on assertions when compiling the driver.
 */

#ifndef ti_drivers_aesctrdrbg_AESCTRDRBGXX__include
#define ti_drivers_aesctrdrbg_AESCTRDRBGXX__include

#include <stdint.h>
#include <stdbool.h>

#include <ti/drivers/AESCTRDRBG.h>

#ifdef __cplusplus
extern "C" {
#endif

#ifndef AESCTRDRBG_MAX_KEY_LENGTH
    #define AESCTRDRBG_MAX_KEY_LENGTH AESCTRDRBG_AES_KEY_LENGTH_256
#endif

#define AESCTRDRBG_MAX_SEED_LENGTH (AESCTRDRBG_MAX_KEY_LENGTH + AESCTRDRBG_AES_BLOCK_SIZE_BYTES)

typedef struct {
    uint_least8_t   aesctrIndex;    
} AESCTRDRBGXX_HWAttrs;

typedef struct {
    uint8_t                         keyingMaterial[AESCTRDRBG_AES_KEY_LENGTH_256];
    uint8_t                         counter[AESCTRDRBG_AES_BLOCK_SIZE_BYTES];
    CryptoKey                       key;
    AESCTR_Handle                   ctrHandle;
    size_t                          seedLength;
    uint32_t                        reseedCounter;
    uint32_t                        reseedInterval;
    int_fast16_t                    returnStatus;
    bool                            isOpen;
} AESCTRDRBGXX_Object;

#ifdef __cplusplus
}
#endif

#endif /* ti_drivers_aesctrdrbg_AESCTRDRBGXX__include */