diff --git a/plat/arm/board/corstone700/corstone700_stack_protector.c b/plat/arm/board/corstone700/corstone700_stack_protector.c new file mode 100644 index 000000000..6fd09da5b --- /dev/null +++ b/plat/arm/board/corstone700/corstone700_stack_protector.c @@ -0,0 +1,35 @@ +/* + * Copyright (c) 2020, ARM Limited and Contributors. All rights reserved. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#include + +#include +#include + +static uint32_t plat_generate_random_number(void) +{ + uintptr_t return_addr = (uintptr_t)__builtin_return_address(0U); + uintptr_t frame_addr = (uintptr_t)__builtin_frame_address(0U); + uint64_t cntpct = read_cntpct_el0(); + + /* Generate 32-bit pattern: saving the 2 least significant bytes + * in random_lo and random_hi + */ + uint16_t random_lo = (uint16_t)( + (((uint64_t)return_addr) << 13) ^ frame_addr ^ cntpct + ); + + uint16_t random_hi = (uint16_t)( + (((uint64_t)frame_addr) << 15) ^ return_addr ^ cntpct + ); + + return (((uint32_t)random_hi) << 16) | random_lo; +} + +u_register_t plat_get_stack_protector_canary(void) +{ + return plat_generate_random_number(); /* a 32-bit pattern is returned */ +} diff --git a/plat/arm/board/corstone700/sp_min/sp_min-corstone700.mk b/plat/arm/board/corstone700/sp_min/sp_min-corstone700.mk index 57e1ec3e4..acee6c39c 100644 --- a/plat/arm/board/corstone700/sp_min/sp_min-corstone700.mk +++ b/plat/arm/board/corstone700/sp_min/sp_min-corstone700.mk @@ -1,5 +1,5 @@ # -# Copyright (c) 2019, Arm Limited and Contributors. All rights reserved. +# Copyright (c) 2019-2020, Arm Limited and Contributors. All rights reserved. # # SPDX-License-Identifier: BSD-3-Clause # @@ -15,4 +15,10 @@ BL32_SOURCES += drivers/cfi/v2m/v2m_flash.c \ plat/arm/board/corstone700/sp_min/corstone700_sp_min_setup.c \ ${CORSTONE700_GIC_SOURCES} +ifneq (${ENABLE_STACK_PROTECTOR},0) + ifneq (${ENABLE_STACK_PROTECTOR},none) + BL32_SOURCES += plat/arm/board/corstone700/corstone700_stack_protector.c + endif +endif + include plat/arm/common/sp_min/arm_sp_min.mk