dp-arm | b3263b3 | 2017-02-28 14:43:15 +0000 | [diff] [blame] | 1 | /* |
2 | * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved. | ||||
3 | * | ||||
dp-arm | fa3cf0b | 2017-05-03 09:38:09 +0100 | [diff] [blame] | 4 | * SPDX-License-Identifier: BSD-3-Clause |
dp-arm | b3263b3 | 2017-02-28 14:43:15 +0000 | [diff] [blame] | 5 | */ |
6 | |||||
7 | #include <arch_helpers.h> | ||||
Antonio Nino Diaz | e0f9063 | 2018-12-14 00:18:21 +0000 | [diff] [blame] | 8 | #include <common/debug.h> |
9 | #include <lib/utils.h> | ||||
Antonio Nino Diaz | a320ecd | 2019-01-15 14:19:50 +0000 | [diff] [blame] | 10 | #include <platform_def.h> |
Antonio Nino Diaz | e0f9063 | 2018-12-14 00:18:21 +0000 | [diff] [blame] | 11 | |
dp-arm | b3263b3 | 2017-02-28 14:43:15 +0000 | [diff] [blame] | 12 | #include "juno_decl.h" |
dp-arm | b3263b3 | 2017-02-28 14:43:15 +0000 | [diff] [blame] | 13 | |
14 | u_register_t plat_get_stack_protector_canary(void) | ||||
15 | { | ||||
Andre Przywara | 927b399 | 2020-10-08 00:43:50 +0100 | [diff] [blame^] | 16 | uint64_t entropy; |
dp-arm | b3263b3 | 2017-02-28 14:43:15 +0000 | [diff] [blame] | 17 | |
Andre Przywara | 927b399 | 2020-10-08 00:43:50 +0100 | [diff] [blame^] | 18 | if (!juno_getentropy(&entropy)) { |
dp-arm | b3263b3 | 2017-02-28 14:43:15 +0000 | [diff] [blame] | 19 | ERROR("Not enough entropy to initialize canary value\n"); |
20 | panic(); | ||||
21 | } | ||||
22 | |||||
Andre Przywara | 927b399 | 2020-10-08 00:43:50 +0100 | [diff] [blame^] | 23 | if (sizeof(entropy) == sizeof(u_register_t)) { |
24 | return entropy; | ||||
25 | } | ||||
26 | |||||
27 | return (entropy & 0xffffffffULL) ^ (entropy >> 32); | ||||
dp-arm | b3263b3 | 2017-02-28 14:43:15 +0000 | [diff] [blame] | 28 | } |