esp-idf/components/esp_rom/include/esp32/rom/secure_boot.h
2023-03-03 22:26:39 +00:00

123 lines
3.8 KiB
C

/*
* SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD
*
* SPDX-License-Identifier: Apache-2.0
*/
#include "sdkconfig.h"
#pragma once
#include <stdint.h>
#include "ets_sys.h"
#include "esp_assert.h"
#ifdef __cplusplus
extern "C" {
#endif
void ets_secure_boot_start(void);
void ets_secure_boot_finish(void);
void ets_secure_boot_hash(const uint32_t *buf);
void ets_secure_boot_obtain(void);
int ets_secure_boot_check(uint32_t *buf);
void ets_secure_boot_rd_iv(uint32_t *buf);
void ets_secure_boot_rd_abstract(uint32_t *buf);
bool ets_secure_boot_check_start(uint8_t abs_index, uint32_t iv_addr);
int ets_secure_boot_check_finish(uint32_t *abstract);
#if CONFIG_ESP32_REV_MIN_FULL >= 300
#include "rsa_pss.h"
#define SECURE_BOOT_NUM_BLOCKS 1
#define CRC_SIGN_BLOCK_LEN 1196
#define SIG_BLOCK_PADDING 4096
#define ETS_SECURE_BOOT_V2_SIGNATURE_MAGIC 0xE7
// Anti-FI measure: use full words for success/fail internally, instead of 0/non-zero
typedef enum {
SBV2_SUCCESS = 0x3A5A5AA5,
SB_SUCCESS = 0x3A5A5AA5,
SBV2_FAILED = 0xA533885A,
SB_FAILED = 0xA533885A,
} secure_boot_v2_status_t;
/* Secure Boot Version 2 signature format for ESP32 ECO3 */
typedef struct {
uint8_t magic_byte;
uint8_t version;
uint8_t _reserved1;
uint8_t _reserved2;
uint8_t image_digest[32];
ets_rsa_pubkey_t key;
uint8_t signature[384];
uint32_t block_crc;
uint8_t _padding[16];
} ets_secure_boot_sig_block_t;
ESP_STATIC_ASSERT(sizeof(ets_secure_boot_sig_block_t) == 1216, "invalid sig block size");
/* ROM supports up to 3, but IDF only checks the first one (SECURE_BOOT_NUM_BLOCKS) */
#define SECURE_BOOT_MAX_APPENDED_SIGN_BLOCKS_TO_IMAGE 3
/* Multiple key block support */
typedef struct {
ets_secure_boot_sig_block_t block[SECURE_BOOT_MAX_APPENDED_SIGN_BLOCKS_TO_IMAGE];
uint8_t _padding[4096 - (sizeof(ets_secure_boot_sig_block_t) * SECURE_BOOT_MAX_APPENDED_SIGN_BLOCKS_TO_IMAGE)];
} ets_secure_boot_signature_t;
ESP_STATIC_ASSERT(sizeof(ets_secure_boot_signature_t) == 4096, "invalid sig sector size");
typedef struct {
const void *key_digests[SECURE_BOOT_NUM_BLOCKS];
} ets_secure_boot_key_digests_t;
/** @brief Verifies the signature block appended to a firmware image. Implemented in the ROM.
*
* This function is used to verify the bootloader before burning its public key hash into Efuse.
* Also, it is used to verify the app on loading the image on boot and on OTA.
*
* @param sig The signature block flashed aligned 4096 bytes from the firmware. (ROM implementation expects 3 blocks, sig->block[3]).
* @param image_digest The SHA-256 Digest of the firmware to be verified
* @param trusted_key_digest The SHA-256 Digest of the public key (ets_rsa_pubkey_t) of a single signature block.
* @param verified_digest RSA-PSS signature of image_digest. Pass an uninitialised array.
*
* @return SBV2_SUCCESS if signature is valid
* SBV2_FAILED for failures.
*/
secure_boot_v2_status_t ets_secure_boot_verify_signature(const ets_secure_boot_signature_t *sig, const uint8_t *image_digest, const uint8_t *trusted_key_digest, uint8_t *verified_digest);
/** @brief This function verifies the 1st stage bootloader. Implemented in the ROM.
* Reboots post verification. It reads the Efuse key for verification of the public key.
*
* This function is not used in the current workflow.
*
*/
void ets_secure_boot_verify_boot_bootloader(void);
/** @brief Confirms if the secure boot V2 has been enabled. Implemented in the ROM.
*
* In ESP32-ECO3 - It checks the value of ABS_DONE_1 in EFuse.
*
* @return true if is Secure boot v2 has been enabled
* False if Secure boot v2 has not been enabled.
*/
bool ets_use_secure_boot_v2(void);
#else
#define SECURE_BOOT_NUM_BLOCKS 0
#endif /* CONFIG_ESP32_REV_MIN_FULL >= 300 */
#ifdef __cplusplus
}
#endif