blob: 50f463b9a0f7036cfa9f73e5a9c4744901df7b54 [file] [log] [blame]
Jiafei Pan46367ad2018-03-02 07:23:30 +00001/*
2 * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6
7#include <arch_helpers.h>
8#include <stdint.h>
9
10#define RANDOM_CANARY_VALUE ((u_register_t) 3288484550995823360ULL)
11
12u_register_t plat_get_stack_protector_canary(void)
13{
14 /*
15 * Ideally, a random number should be returned instead of the
16 * combination of a timer's value and a compile-time constant. As the
17 * FVP does not have any random number generator, this is better than
18 * nothing but not necessarily really secure.
19 */
20 return RANDOM_CANARY_VALUE ^ read_cntpct_el0();
21}