blob: 815f73135dd94e895ebbbc4043e517ec9d968758 [file] [log] [blame]
/*
* Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <stdint.h>
#include <lib/utils.h>
#include "rpi3_private.h"
/* Get 128 bits of entropy and fuse the values together to form the canary. */
#define TRNG_NBYTES 16U
u_register_t plat_get_stack_protector_canary(void)
{
size_t i;
u_register_t buf[TRNG_NBYTES / sizeof(u_register_t)];
u_register_t ret = 0U;
rpi3_rng_read(buf, sizeof(buf));
for (i = 0U; i < ARRAY_SIZE(buf); i++)
ret ^= buf[i];
return ret;
}