nrf_cc3xx_platform_hmac_drbg_get_with_add()

int nrf_cc3xx_platform_hmac_drbg_get_with_add	(	nrf_cc3xx_platform_hmac_drbg_context_t *const	context,
		uint8_t *	buffer,
		size_t	len,
		size_t *	olen,
		const uint8_t *	additional,
		size_t	add_len )

#include <crypto/nrf_cc310_platform/include/nrf_cc3xx_platform_hmac_drbg.h>

Function to get PRNG using hmac_drbg and an additional string of data.

Note

If the context is NULL the function uses an internal context.

This function will calculate PRNG using HW accelerated HMAC(with SHA256) with a 16-byte key and reseed with TRNG using ARM CryptoCell cc3xx HW according to a reseed interval.

This function calculates random numbers using PRNG seeded by TRNG as defined in NIST SP 800-90A: Recommendation for Random Number Generation Using Deterministic Random Bit Generators. The random numbers are generated using Arm CryptoCell cc3xx hardware acceleration.

Note

Before calling this API the context to must be initialized by calling nrf_cc3xx_platform_hmac_drbg_init.

This API is only usable if nrf_cc3xx_platform initialization APIs was run prior to calling it.

Parameters

[in,out]	context	Pointer to structure holding the hmac_drbg context.
[out]	buffer	Pointer to buffer to hold PRNG data.
[in]	len	Length of PRNG to get in bytes.
[out]	olen	Length reported output in bytes.
[in]	additional	Additional input to use with HMAC_DRBG_Generate_algorithm.
[in]	add_len	Length of HMAC_DRBG additional input in bytes.

Returns

NRF_CC3XX_PLATFORM_SUCCESS on success, otherwise a non-zero failure according to the API mbedtls_hmac_drbg_get_with_add.