kopia lustrzana https://github.com/espressif/esp-idf
95 wiersze
3.8 KiB
C
95 wiersze
3.8 KiB
C
// Copyright 2020 Espressif Systems (Shanghai) PTE LTD
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
#include "sdkconfig.h"
|
|
#include "soc/rtc_cntl_reg.h"
|
|
#include "esp_rom_sys.h"
|
|
|
|
#pragma once
|
|
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
/**
|
|
* @brief Assert a condition is true, in a way that should be resistant to fault injection for
|
|
* single fault attacks.
|
|
*
|
|
* - Expands CONDITION multiple times (condition must have no side effects)
|
|
* - Compiler is told all registers are invalid before evaluating CONDITION each time, to avoid a fault
|
|
* causing a misread of a register used in all three evaluations of CONDITION.
|
|
* - If CONDITION is ever false, a system reset is triggered.
|
|
*
|
|
* @note Place this macro after a "normal" check of CONDITION that will fail with a normal error
|
|
* message. This is the fallback in case a fault injection attack skips or corrupts the result of
|
|
* that check. (Although ensure that an attacker can't use fault injection to skip past the "normal"
|
|
* error message, to avoid this check entirely.)
|
|
*
|
|
* @note This macro increases binary size and is slow and should be used sparingly.
|
|
*
|
|
* @note This macro does not guarantee fault injection resistance. In particular CONDITION must be
|
|
* chosen carefully - a fault injection attack which sets CONDITION to true will not be detected by
|
|
* this macro. Care must also be taken that an attacker can't use a fault to completely bypass calling
|
|
* whatever function tests ESP_FAULT_ASSERT.
|
|
*
|
|
* @note This is difficult to debug as a failure triggers an instant software reset, and UART output
|
|
* is often truncated (as FIFO is not flushed). Define the ESP_FAULT_ASSERT_DEBUG macro to debug any
|
|
* failures of this macro due to software bugs.
|
|
*
|
|
* @param CONDITION A condition which will evaluate true unless an attacker used fault injection to skip or corrupt some other critical system calculation.
|
|
*
|
|
*/
|
|
#define ESP_FAULT_ASSERT(CONDITION) do { \
|
|
asm volatile ("" ::: "memory"); \
|
|
if(!(CONDITION)) _ESP_FAULT_RESET(); \
|
|
asm volatile ("" ::: "memory"); \
|
|
if(!(CONDITION)) _ESP_FAULT_RESET(); \
|
|
asm volatile ("" ::: "memory"); \
|
|
if(!(CONDITION)) _ESP_FAULT_RESET(); \
|
|
} while(0)
|
|
|
|
|
|
// Uncomment this macro to get debug output if ESP_FAULT_ASSERT() fails
|
|
//
|
|
// Note that uncommenting this macro reduces the anti-FI effectiveness
|
|
//
|
|
//#define ESP_FAULT_ASSERT_DEBUG
|
|
|
|
/* Internal macro, purpose is to trigger a system reset if an inconsistency due to fault injection
|
|
is detected.
|
|
|
|
Illegal instruction opcodes are there as a fallback to crash the CPU in case it doesn't
|
|
reset as expected.
|
|
*/
|
|
#ifndef ESP_FAULT_ASSERT_DEBUG
|
|
|
|
#define _ESP_FAULT_RESET() do { \
|
|
REG_WRITE(RTC_CNTL_OPTIONS0_REG, RTC_CNTL_SW_SYS_RST); \
|
|
asm volatile("ill; ill; ill;"); \
|
|
} while(0)
|
|
|
|
#else // ESP_FAULT_ASSERT_DEBUG
|
|
|
|
#warning "Enabling ESP_FAULT_ASSERT_DEBUG makes ESP_FAULT_ASSERT() less effective"
|
|
|
|
#define _ESP_FAULT_RESET() do { \
|
|
esp_rom_printf("ESP_FAULT_ASSERT %s:%d\n", __FILE__, __LINE__); \
|
|
asm volatile("ill;"); \
|
|
} while(0)
|
|
|
|
#endif // ESP_FAULT_ASSERT_DEBUG
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|