Mbed TLS PSA random-source adapter for the HTTPS client demo. More...

#include <stddef.h>
#include <stdint.h>
#include "ra8_check.h"
#include "ra8_err.h"
#include "ra8_rsip.h"
#include "psa/crypto.h"

Include dependency graph for mbedtls_psa_rng.c:

Functions
psa_status_t	mbedtls_psa_external_get_random (mbedtls_psa_external_random_context_t context, uint8_t output, size_t output_size, size_t *output_length)
	PSA external RNG hook – feeds RSIP TRNG straight into PSA.

Detailed Description

Mbed TLS PSA random-source adapter for the HTTPS client demo.

Tag: [Ring 6 / APP] {World: S}

Implements the Mbed TLS external PSA random callback using the RA8D2 RSIP true-random generator. Keeping the vendor callback in its own translation unit isolates the TLS adaptation boundary from the ThreadX and HTTP session orchestration in main.c.

Author: Brighton Sikarskie

Date: 2026-08-27

Copyright: Copyright (c) 2026 Brighton Sikarskie SPDX-License-Identifier: MIT

Since: 0.1.0

Definition in file mbedtls_psa_rng.c.

Function Documentation

◆ mbedtls_psa_external_get_random()

psa_status_t mbedtls_psa_external_get_random	(	mbedtls_psa_external_random_context_t *	context,
		uint8_t *	output,
		size_t	output_size,
		size_t *	output_length )

PSA external RNG hook – feeds RSIP TRNG straight into PSA.

Mbed TLS 4.x removed MBEDTLS_ENTROPY_C / MBEDTLS_CTR_DRBG_C from the standard build path. With MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG the SSL layer pulls random bytes from this callback (via psa_generate_random) instead of running an in-tree DRBG.

Parameters

[in,out]	context	PSA's per-process external RNG context (unused).
[out]	output	Output buffer.
[in]	output_size	Bytes requested.
[out]	output_length	Bytes actually produced.

Returns: PSA status describing whether random generation succeeded.

Return values

PSA_SUCCESS	Exactly `output_size` random bytes were produced.
PSA_ERROR_INVALID_ARGUMENT	An output pointer is null.
PSA_ERROR_HARDWARE_FAILURE	The RSIP TRNG returned an error.

Precondition: RSIP has been initialized by ra8_rsip_init().; output and output_length are non-null caller-owned storage.

Postcondition: On success output contains output_size bytes from the RSIP TRNG.; On success output_length equals output_size.; An invalid pointer emits an error log before returning PSA_ERROR_INVALID_ARGUMENT; no output storage is modified.

Note: Not thread-safe; callers must serialize across threads.

See also: psa_generate_random; ra8_rsip_trng_read

Since: 0.1.0

Definition at line 54 of file mbedtls_psa_rng.c.

References k_ra8_ok, RA8_CHECK_NULL_PTR_RETURN, and ra8_rsip_trng_read().

Functions

Detailed Description

Function Documentation

◆ mbedtls_psa_external_get_random()