| Jiafei Pan | 46367ad | 2018-03-02 07:23:30 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved. |
| 3 | * |
| 4 | * SPDX-License-Identifier: BSD-3-Clause |
| 5 | */ |
| 6 | |
| Jiafei Pan | 46367ad | 2018-03-02 07:23:30 +0000 | [diff] [blame] | 7 | #include <stdint.h> |
| 8 | |
| Antonio Nino Diaz | e0f9063 | 2018-12-14 00:18:21 +0000 | [diff] [blame] | 9 | #include <arch_helpers.h> |
| 10 | |
| Jiafei Pan | 46367ad | 2018-03-02 07:23:30 +0000 | [diff] [blame] | 11 | #define RANDOM_CANARY_VALUE ((u_register_t) 3288484550995823360ULL) |
| 12 | |
| 13 | u_register_t plat_get_stack_protector_canary(void) |
| 14 | { |
| 15 | /* |
| 16 | * Ideally, a random number should be returned instead of the |
| 17 | * combination of a timer's value and a compile-time constant. As the |
| 18 | * FVP does not have any random number generator, this is better than |
| 19 | * nothing but not necessarily really secure. |
| 20 | */ |
| 21 | return RANDOM_CANARY_VALUE ^ read_cntpct_el0(); |
| 22 | } |