1*91f16700Schasinglulu /* 2*91f16700Schasinglulu * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved. 3*91f16700Schasinglulu * 4*91f16700Schasinglulu * SPDX-License-Identifier: BSD-3-Clause 5*91f16700Schasinglulu */ 6*91f16700Schasinglulu 7*91f16700Schasinglulu #include <stdint.h> 8*91f16700Schasinglulu 9*91f16700Schasinglulu #include <arch_helpers.h> 10*91f16700Schasinglulu #include <plat/common/platform.h> 11*91f16700Schasinglulu 12*91f16700Schasinglulu #define RANDOM_CANARY_VALUE 2144346116U 13*91f16700Schasinglulu 14*91f16700Schasinglulu u_register_t plat_get_stack_protector_canary(void) 15*91f16700Schasinglulu { 16*91f16700Schasinglulu /* 17*91f16700Schasinglulu * Ideally, a random number should be returned instead of the 18*91f16700Schasinglulu * combination of a timer's value and a compile-time constant. 19*91f16700Schasinglulu */ 20*91f16700Schasinglulu return RANDOM_CANARY_VALUE ^ (u_register_t)read_cntpct_el0(); 21*91f16700Schasinglulu } 22*91f16700Schasinglulu 23