mirror of
https://github.com/espressif/esp-idf.git
synced 2024-10-05 20:47:46 -04:00
bootloader_support: Removes old code of SB and FE for esp32h2
This commit is contained in:
KonstantinKondrashov
parent
019be31a6c
commit
f761cee32e
@ -1,346 +0,0 @@
|
||||
/*
|
||||
* SPDX-FileCopyrightText: 2015-2021 Espressif Systems (Shanghai) CO LTD
|
||||
*
|
||||
* SPDX-License-Identifier: Apache-2.0
|
||||
*/
|
||||
|
||||
#include <strings.h>
|
||||
#include "bootloader_flash_priv.h"
|
||||
#include "bootloader_random.h"
|
||||
#include "bootloader_utility.h"
|
||||
#include "esp_image_format.h"
|
||||
#include "esp_flash_encrypt.h"
|
||||
#include "esp_flash_partitions.h"
|
||||
#include "esp_secure_boot.h"
|
||||
#include "esp_log.h"
|
||||
#include "esp32h2/rom/secure_boot.h"
|
||||
#include "esp_efuse.h"
|
||||
#include "esp_efuse_table.h"
|
||||
#include "hal/wdt_hal.h"
|
||||
|
||||
static const char *TAG = "flash_encrypt";
|
||||
|
||||
/* Static functions for stages of flash encryption */
|
||||
static esp_err_t initialise_flash_encryption(void);
|
||||
static esp_err_t encrypt_flash_contents(uint32_t flash_crypt_cnt, bool flash_crypt_wr_dis) __attribute__((unused));
|
||||
static esp_err_t encrypt_bootloader(void);
|
||||
static esp_err_t encrypt_and_load_partition_table(esp_partition_info_t *partition_table, int *num_partitions);
|
||||
static esp_err_t encrypt_partition(int index, const esp_partition_info_t *partition);
|
||||
|
||||
esp_err_t esp_flash_encrypt_check_and_update(void)
|
||||
{
|
||||
uint8_t flash_crypt_wr_dis = 0;
|
||||
uint32_t flash_crypt_cnt = 0;
|
||||
|
||||
esp_efuse_read_field_blob(ESP_EFUSE_SPI_BOOT_CRYPT_CNT, &flash_crypt_cnt, 3);
|
||||
esp_efuse_read_field_blob(ESP_EFUSE_WR_DIS_SPI_BOOT_CRYPT_CNT, &flash_crypt_wr_dis, 1);
|
||||
|
||||
ESP_LOGV(TAG, "SPI_BOOT_CRYPT_CNT 0x%x", flash_crypt_cnt);
|
||||
ESP_LOGV(TAG, "EFUSE_WR_DIS_SPI_BOOT_CRYPT_CNT 0x%x", flash_crypt_wr_dis);
|
||||
|
||||
if (__builtin_parity(flash_crypt_cnt) == 1) {
|
||||
/* Flash is already encrypted */
|
||||
int left = (flash_crypt_cnt == 1) ? 1 : 0;
|
||||
if (flash_crypt_wr_dis) {
|
||||
left = 0; /* can't update FLASH_CRYPT_CNT, no more flashes */
|
||||
}
|
||||
ESP_LOGI(TAG, "flash encryption is enabled (%d plaintext flashes left)", left);
|
||||
return ESP_OK;
|
||||
} else {
|
||||
#ifndef CONFIG_SECURE_FLASH_REQUIRE_ALREADY_ENABLED
|
||||
/* Flash is not encrypted, so encrypt it! */
|
||||
return encrypt_flash_contents(flash_crypt_cnt, flash_crypt_wr_dis);
|
||||
#else
|
||||
ESP_LOGE(TAG, "flash encryption is not enabled, and SECURE_FLASH_REQUIRE_ALREADY_ENABLED "
|
||||
"is set, refusing to boot.");
|
||||
return ESP_ERR_INVALID_STATE;
|
||||
#endif // CONFIG_SECURE_FLASH_REQUIRE_ALREADY_ENABLED
|
||||
}
|
||||
}
|
||||
|
||||
static esp_err_t check_and_generate_encryption_keys(void)
|
||||
{
|
||||
esp_efuse_block_t aes_128_key_block;
|
||||
|
||||
bool has_key = esp_efuse_find_purpose(ESP_EFUSE_KEY_PURPOSE_XTS_AES_128_KEY, &aes_128_key_block);
|
||||
bool dis_write = false;
|
||||
bool dis_read = false;
|
||||
|
||||
// If there are keys set, they must be write and read protected!
|
||||
if(has_key) {
|
||||
dis_write = esp_efuse_get_key_dis_write(aes_128_key_block);
|
||||
dis_read = esp_efuse_get_key_dis_read(aes_128_key_block);
|
||||
}
|
||||
|
||||
|
||||
if(has_key && (!dis_read || !dis_write)) {
|
||||
ESP_LOGE(TAG, "Invalid key state, a key was set but not read and write protected.");
|
||||
return ESP_ERR_INVALID_STATE;
|
||||
}
|
||||
|
||||
if(!has_key && !dis_write && !dis_read) {
|
||||
ESP_LOGI(TAG, "Generating new flash encryption key...");
|
||||
|
||||
enum { BLOCKS_NEEDED = 1 };
|
||||
esp_efuse_purpose_t purposes[BLOCKS_NEEDED] = {
|
||||
ESP_EFUSE_KEY_PURPOSE_XTS_AES_128_KEY,
|
||||
};
|
||||
|
||||
uint8_t keys[BLOCKS_NEEDED][32] = { 0 };
|
||||
for (int i = 0; i < BLOCKS_NEEDED; ++i) {
|
||||
bootloader_fill_random(keys[i], 32);
|
||||
}
|
||||
|
||||
esp_err_t err = esp_efuse_write_keys(purposes, keys, BLOCKS_NEEDED);
|
||||
if (err != ESP_OK) {
|
||||
if (err == ESP_ERR_NOT_ENOUGH_UNUSED_KEY_BLOCKS) {
|
||||
ESP_LOGE(TAG, "Not enough free efuse key blocks (need %d) to continue", BLOCKS_NEEDED);
|
||||
} else {
|
||||
ESP_LOGE(TAG, "Failed to write efuse block with purpose (err=0x%x). Can't continue.", err);
|
||||
}
|
||||
return err;
|
||||
}
|
||||
ESP_LOGD(TAG, "Key generation complete");
|
||||
return ESP_OK;
|
||||
|
||||
} else {
|
||||
ESP_LOGI(TAG, "Using pre-existing key in efuse");
|
||||
return ESP_OK;
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
static esp_err_t initialise_flash_encryption(void)
|
||||
{
|
||||
esp_efuse_batch_write_begin(); /* Batch all efuse writes at the end of this function */
|
||||
|
||||
esp_err_t key_state = check_and_generate_encryption_keys();
|
||||
if(key_state != ESP_OK) {
|
||||
esp_efuse_batch_write_cancel();
|
||||
return key_state;
|
||||
}
|
||||
|
||||
#ifndef CONFIG_SECURE_FLASH_UART_BOOTLOADER_ALLOW_ENC
|
||||
ESP_LOGI(TAG, "Disable UART bootloader encryption...");
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_DIS_DOWNLOAD_MANUAL_ENCRYPT);
|
||||
#else
|
||||
ESP_LOGW(TAG, "Not disabling UART bootloader encryption");
|
||||
#endif
|
||||
|
||||
#ifndef CONFIG_SECURE_FLASH_UART_BOOTLOADER_ALLOW_CACHE
|
||||
ESP_LOGI(TAG, "Disable UART bootloader cache...");
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_DIS_DOWNLOAD_ICACHE);
|
||||
#else
|
||||
ESP_LOGW(TAG, "Not disabling UART bootloader cache - SECURITY COMPROMISED");
|
||||
#endif
|
||||
|
||||
#ifndef CONFIG_SECURE_BOOT_ALLOW_JTAG
|
||||
ESP_LOGI(TAG, "Disable JTAG...");
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_DIS_PAD_JTAG);
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_DIS_USB_JTAG);
|
||||
#else
|
||||
ESP_LOGW(TAG, "Not disabling JTAG - SECURITY COMPROMISED");
|
||||
#endif
|
||||
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_DIS_LEGACY_SPI_BOOT);
|
||||
|
||||
esp_err_t err = esp_efuse_batch_write_commit();
|
||||
if (err != ESP_OK) {
|
||||
ESP_LOGE(TAG, "Error programming security eFuses (err=0x%x).", err);
|
||||
}
|
||||
|
||||
return err;
|
||||
}
|
||||
|
||||
/* Encrypt all flash data that should be encrypted */
|
||||
static esp_err_t encrypt_flash_contents(uint32_t spi_boot_crypt_cnt, bool flash_crypt_wr_dis)
|
||||
{
|
||||
esp_err_t err;
|
||||
esp_partition_info_t partition_table[ESP_PARTITION_TABLE_MAX_ENTRIES];
|
||||
int num_partitions;
|
||||
|
||||
/* If the last spi_boot_crypt_cnt bit is burned or write-disabled, the
|
||||
device can't re-encrypt itself. */
|
||||
if (flash_crypt_wr_dis || spi_boot_crypt_cnt == EFUSE_SPI_BOOT_CRYPT_CNT) {
|
||||
ESP_LOGE(TAG, "Cannot re-encrypt data SPI_BOOT_CRYPT_CNT 0x%02x write disabled %d", spi_boot_crypt_cnt, flash_crypt_wr_dis);
|
||||
return ESP_FAIL;
|
||||
}
|
||||
|
||||
if (spi_boot_crypt_cnt == 0) {
|
||||
/* Very first flash of encrypted data: generate keys, etc. */
|
||||
err = initialise_flash_encryption();
|
||||
if (err != ESP_OK) {
|
||||
return err;
|
||||
}
|
||||
}
|
||||
|
||||
err = encrypt_bootloader();
|
||||
if (err != ESP_OK) {
|
||||
return err;
|
||||
}
|
||||
|
||||
err = encrypt_and_load_partition_table(partition_table, &num_partitions);
|
||||
if (err != ESP_OK) {
|
||||
return err;
|
||||
}
|
||||
|
||||
/* Now iterate the just-loaded partition table, looking for entries to encrypt
|
||||
*/
|
||||
|
||||
/* Go through each partition and encrypt if necessary */
|
||||
for (int i = 0; i < num_partitions; i++) {
|
||||
err = encrypt_partition(i, &partition_table[i]);
|
||||
if (err != ESP_OK) {
|
||||
return err;
|
||||
}
|
||||
}
|
||||
|
||||
ESP_LOGD(TAG, "All flash regions checked for encryption pass");
|
||||
|
||||
/* Set least significant 0-bit in spi_boot_crypt_cnt */
|
||||
int ffs_inv = __builtin_ffs((~spi_boot_crypt_cnt) & 0x7);
|
||||
/* ffs_inv shouldn't be zero, as zero implies spi_boot_crypt_cnt == 0xFF */
|
||||
uint32_t new_spi_boot_crypt_cnt = (1 << (ffs_inv - 1));
|
||||
ESP_LOGD(TAG, "SPI_BOOT_CRYPT_CNT 0x%x -> 0x%x", spi_boot_crypt_cnt, new_spi_boot_crypt_cnt + spi_boot_crypt_cnt);
|
||||
|
||||
esp_efuse_write_field_blob(ESP_EFUSE_SPI_BOOT_CRYPT_CNT, &new_spi_boot_crypt_cnt, 3);
|
||||
|
||||
#ifdef CONFIG_SECURE_FLASH_ENCRYPTION_MODE_RELEASE
|
||||
//Secure SPI boot cnt after its update if needed.
|
||||
const uint32_t spi_boot_cnt_wr_dis = 1;
|
||||
ESP_LOGI(TAG, "Write protecting SPI_CRYPT_CNT eFuse");
|
||||
esp_efuse_write_field_blob(ESP_EFUSE_WR_DIS_SPI_BOOT_CRYPT_CNT, &spi_boot_cnt_wr_dis, 1);
|
||||
#endif
|
||||
ESP_LOGI(TAG, "Flash encryption completed");
|
||||
|
||||
return ESP_OK;
|
||||
}
|
||||
|
||||
static esp_err_t encrypt_bootloader(void)
|
||||
{
|
||||
esp_err_t err;
|
||||
uint32_t image_length;
|
||||
/* Check for plaintext bootloader (verification will fail if it's already encrypted) */
|
||||
if (esp_image_verify_bootloader(&image_length) == ESP_OK) {
|
||||
ESP_LOGD(TAG, "bootloader is plaintext. Encrypting...");
|
||||
|
||||
#if CONFIG_SECURE_BOOT_V2_ENABLED
|
||||
/* The image length obtained from esp_image_verify_bootloader includes the sector boundary padding and the signature block lengths */
|
||||
if (ESP_BOOTLOADER_OFFSET + image_length > ESP_PARTITION_TABLE_OFFSET) {
|
||||
ESP_LOGE(TAG, "Bootloader is too large to fit Secure Boot V2 signature sector and partition table (configured offset 0x%x)", ESP_PARTITION_TABLE_OFFSET);
|
||||
return ESP_ERR_INVALID_SIZE;
|
||||
}
|
||||
#endif // CONFIG_SECURE_BOOT_V2_ENABLED
|
||||
|
||||
err = esp_flash_encrypt_region(ESP_BOOTLOADER_OFFSET, image_length);
|
||||
if (err != ESP_OK) {
|
||||
ESP_LOGE(TAG, "Failed to encrypt bootloader in place: 0x%x", err);
|
||||
return err;
|
||||
}
|
||||
|
||||
ESP_LOGI(TAG, "bootloader encrypted successfully");
|
||||
return err;
|
||||
}
|
||||
else {
|
||||
ESP_LOGW(TAG, "no valid bootloader was found");
|
||||
return ESP_ERR_NOT_FOUND;
|
||||
}
|
||||
}
|
||||
|
||||
static esp_err_t encrypt_and_load_partition_table(esp_partition_info_t *partition_table, int *num_partitions)
|
||||
{
|
||||
esp_err_t err;
|
||||
/* Check for plaintext partition table */
|
||||
err = bootloader_flash_read(ESP_PARTITION_TABLE_OFFSET, partition_table, ESP_PARTITION_TABLE_MAX_LEN, false);
|
||||
if (err != ESP_OK) {
|
||||
ESP_LOGE(TAG, "Failed to read partition table data");
|
||||
return err;
|
||||
}
|
||||
if (esp_partition_table_verify(partition_table, false, num_partitions) == ESP_OK) {
|
||||
ESP_LOGD(TAG, "partition table is plaintext. Encrypting...");
|
||||
esp_err_t err = esp_flash_encrypt_region(ESP_PARTITION_TABLE_OFFSET,
|
||||
FLASH_SECTOR_SIZE);
|
||||
if (err != ESP_OK) {
|
||||
ESP_LOGE(TAG, "Failed to encrypt partition table in place. %x", err);
|
||||
return err;
|
||||
}
|
||||
} else {
|
||||
ESP_LOGE(TAG, "Failed to read partition table data - not plaintext?");
|
||||
return ESP_ERR_INVALID_STATE;
|
||||
}
|
||||
|
||||
/* Valid partition table loaded */
|
||||
ESP_LOGI(TAG, "partition table encrypted and loaded successfully");
|
||||
return ESP_OK;
|
||||
}
|
||||
|
||||
|
||||
static esp_err_t encrypt_partition(int index, const esp_partition_info_t *partition)
|
||||
{
|
||||
esp_err_t err;
|
||||
bool should_encrypt = (partition->flags & PART_FLAG_ENCRYPTED);
|
||||
|
||||
if (partition->type == PART_TYPE_APP) {
|
||||
/* check if the partition holds a valid unencrypted app */
|
||||
esp_image_metadata_t data_ignored;
|
||||
err = esp_image_verify(ESP_IMAGE_VERIFY,
|
||||
&partition->pos,
|
||||
&data_ignored);
|
||||
should_encrypt = (err == ESP_OK);
|
||||
} else if (partition->type == PART_TYPE_DATA && partition->subtype == PART_SUBTYPE_DATA_OTA) {
|
||||
/* check if we have ota data partition and the partition should be encrypted unconditionally */
|
||||
should_encrypt = true;
|
||||
}
|
||||
|
||||
if (!should_encrypt) {
|
||||
return ESP_OK;
|
||||
} else {
|
||||
/* should_encrypt */
|
||||
ESP_LOGI(TAG, "Encrypting partition %d at offset 0x%x (length 0x%x)...", index, partition->pos.offset, partition->pos.size);
|
||||
|
||||
err = esp_flash_encrypt_region(partition->pos.offset, partition->pos.size);
|
||||
ESP_LOGI(TAG, "Done encrypting");
|
||||
if (err != ESP_OK) {
|
||||
ESP_LOGE(TAG, "Failed to encrypt partition %d", index);
|
||||
}
|
||||
return err;
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
esp_err_t esp_flash_encrypt_region(uint32_t src_addr, size_t data_length)
|
||||
{
|
||||
esp_err_t err;
|
||||
uint32_t buf[FLASH_SECTOR_SIZE / sizeof(uint32_t)];
|
||||
|
||||
if (src_addr % FLASH_SECTOR_SIZE != 0) {
|
||||
ESP_LOGE(TAG, "esp_flash_encrypt_region bad src_addr 0x%x", src_addr);
|
||||
return ESP_FAIL;
|
||||
}
|
||||
|
||||
wdt_hal_context_t rtc_wdt_ctx = {.inst = WDT_RWDT, .rwdt_dev = &RTCCNTL};
|
||||
for (size_t i = 0; i < data_length; i += FLASH_SECTOR_SIZE) {
|
||||
wdt_hal_write_protect_disable(&rtc_wdt_ctx);
|
||||
wdt_hal_feed(&rtc_wdt_ctx);
|
||||
wdt_hal_write_protect_enable(&rtc_wdt_ctx);
|
||||
|
||||
uint32_t sec_start = i + src_addr;
|
||||
err = bootloader_flash_read(sec_start, buf, FLASH_SECTOR_SIZE, false);
|
||||
if (err != ESP_OK) {
|
||||
goto flash_failed;
|
||||
}
|
||||
err = bootloader_flash_erase_sector(sec_start / FLASH_SECTOR_SIZE);
|
||||
if (err != ESP_OK) {
|
||||
goto flash_failed;
|
||||
}
|
||||
err = bootloader_flash_write(sec_start, buf, FLASH_SECTOR_SIZE, true);
|
||||
if (err != ESP_OK) {
|
||||
goto flash_failed;
|
||||
}
|
||||
}
|
||||
return ESP_OK;
|
||||
|
||||
flash_failed:
|
||||
ESP_LOGE(TAG, "flash operation failed: 0x%x", err);
|
||||
return err;
|
||||
}
|
||||
@ -0,0 +1,50 @@
|
||||
/*
|
||||
* SPDX-FileCopyrightText: 2015-2021 Espressif Systems (Shanghai) CO LTD
|
||||
*
|
||||
* SPDX-License-Identifier: Apache-2.0
|
||||
*/
|
||||
|
||||
#include <strings.h>
|
||||
#include "esp_flash_encrypt.h"
|
||||
#include "esp_secure_boot.h"
|
||||
#include "esp_efuse.h"
|
||||
#include "esp_efuse_table.h"
|
||||
#include "esp_log.h"
|
||||
#include "sdkconfig.h"
|
||||
|
||||
static __attribute__((unused)) const char *TAG = "flash_encrypt";
|
||||
|
||||
esp_err_t esp_flash_encryption_enable_secure_features(void)
|
||||
{
|
||||
#ifndef CONFIG_SECURE_FLASH_UART_BOOTLOADER_ALLOW_ENC
|
||||
ESP_LOGI(TAG, "Disable UART bootloader encryption...");
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_DIS_DOWNLOAD_MANUAL_ENCRYPT);
|
||||
#else
|
||||
ESP_LOGW(TAG, "Not disabling UART bootloader encryption");
|
||||
#endif
|
||||
|
||||
#ifndef CONFIG_SECURE_FLASH_UART_BOOTLOADER_ALLOW_CACHE
|
||||
ESP_LOGI(TAG, "Disable UART bootloader cache...");
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_DIS_DOWNLOAD_ICACHE);
|
||||
#else
|
||||
ESP_LOGW(TAG, "Not disabling UART bootloader cache - SECURITY COMPROMISED");
|
||||
#endif
|
||||
|
||||
#ifndef CONFIG_SECURE_BOOT_ALLOW_JTAG
|
||||
ESP_LOGI(TAG, "Disable JTAG...");
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_DIS_PAD_JTAG);
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_DIS_USB_JTAG);
|
||||
#else
|
||||
ESP_LOGW(TAG, "Not disabling JTAG - SECURITY COMPROMISED");
|
||||
#endif
|
||||
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_DIS_LEGACY_SPI_BOOT);
|
||||
|
||||
#if defined(CONFIG_SECURE_BOOT_V2_ENABLED) && !defined(CONFIG_SECURE_BOOT_V2_ALLOW_EFUSE_RD_DIS)
|
||||
// This bit is set when enabling Secure Boot V2, but we can't enable it until this later point in the first boot
|
||||
// otherwise the Flash Encryption key cannot be read protected
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_WR_DIS_RD_DIS);
|
||||
#endif
|
||||
|
||||
return ESP_OK;
|
||||
}
|
||||
@ -1,301 +0,0 @@
|
||||
/*
|
||||
* SPDX-FileCopyrightText: 2015-2021 Espressif Systems (Shanghai) CO LTD
|
||||
*
|
||||
* SPDX-License-Identifier: Apache-2.0
|
||||
*/
|
||||
#include <string.h>
|
||||
|
||||
#include "esp_log.h"
|
||||
#include "esp_secure_boot.h"
|
||||
#include "soc/efuse_reg.h"
|
||||
|
||||
#include "bootloader_flash_priv.h"
|
||||
#include "bootloader_sha.h"
|
||||
#include "bootloader_utility.h"
|
||||
|
||||
#include "esp_rom_crc.h"
|
||||
#include "esp_efuse.h"
|
||||
#include "esp_efuse_table.h"
|
||||
|
||||
#include "esp32h2/rom/efuse.h"
|
||||
#include "esp32h2/rom/secure_boot.h"
|
||||
|
||||
static const char *TAG = "secure_boot_v2";
|
||||
#define ALIGN_UP(num, align) (((num) + ((align) - 1)) & ~((align) - 1))
|
||||
|
||||
/* A signature block is valid when it has correct magic byte, crc and image digest. */
|
||||
static esp_err_t validate_signature_block(const ets_secure_boot_sig_block_t *block, int block_num, const uint8_t *image_digest)
|
||||
{
|
||||
uint32_t crc = esp_rom_crc32_le(0, (uint8_t *)block, CRC_SIGN_BLOCK_LEN);
|
||||
if (block->magic_byte != ETS_SECURE_BOOT_V2_SIGNATURE_MAGIC) {
|
||||
// All signature blocks have been parsed, no new signature block present.
|
||||
ESP_LOGD(TAG, "Signature block(%d) invalid/absent.", block_num);
|
||||
return ESP_FAIL;
|
||||
}
|
||||
if (block->block_crc != crc) {
|
||||
ESP_LOGE(TAG, "Magic byte correct but incorrect crc.");
|
||||
return ESP_FAIL;
|
||||
}
|
||||
if (memcmp(image_digest, block->image_digest, ESP_SECURE_BOOT_DIGEST_LEN)) {
|
||||
ESP_LOGE(TAG, "Magic byte & CRC correct but incorrect image digest.");
|
||||
return ESP_FAIL;
|
||||
} else {
|
||||
ESP_LOGD(TAG, "valid signature block(%d) found", block_num);
|
||||
return ESP_OK;
|
||||
}
|
||||
|
||||
return ESP_FAIL;
|
||||
}
|
||||
|
||||
/* Generates the public key digests of the valid public keys in an image's
|
||||
signature block, verifies each signature, and stores the key digests in the
|
||||
public_key_digests structure.
|
||||
|
||||
@param flash_offset Image offset in flash
|
||||
@param flash_size Image size in flash (not including signature block)
|
||||
@param[out] public_key_digests Pointer to structure to hold the key digests for valid sig blocks
|
||||
|
||||
|
||||
Note that this function doesn't read any eFuses, so it doesn't know if the
|
||||
keys are ultimately trusted by the hardware or not
|
||||
|
||||
@return - ESP_OK if no signatures failed to verify, or if no valid signature blocks are found at all.
|
||||
- ESP_FAIL if there's a valid signature block that doesn't verify using the included public key (unexpected!)
|
||||
*/
|
||||
static esp_err_t s_calculate_image_public_key_digests(uint32_t flash_offset, uint32_t flash_size, esp_image_sig_public_key_digests_t *public_key_digests)
|
||||
{
|
||||
esp_err_t ret;
|
||||
uint8_t image_digest[ESP_SECURE_BOOT_DIGEST_LEN] = {0};
|
||||
uint8_t __attribute__((aligned(4))) key_digest[ESP_SECURE_BOOT_DIGEST_LEN] = {0};
|
||||
size_t sig_block_addr = flash_offset + ALIGN_UP(flash_size, FLASH_SECTOR_SIZE);
|
||||
|
||||
ESP_LOGD(TAG, "calculating public key digests for sig blocks of image offset 0x%x (sig block offset 0x%x)", flash_offset, sig_block_addr);
|
||||
|
||||
bzero(public_key_digests, sizeof(esp_image_sig_public_key_digests_t));
|
||||
|
||||
ret = bootloader_sha256_flash_contents(flash_offset, sig_block_addr - flash_offset, image_digest);
|
||||
if (ret != ESP_OK) {
|
||||
ESP_LOGE(TAG, "error generating image digest, %d", ret);
|
||||
return ret;
|
||||
}
|
||||
|
||||
ESP_LOGD(TAG, "reading signatures");
|
||||
const ets_secure_boot_signature_t *signatures = bootloader_mmap(sig_block_addr, sizeof(ets_secure_boot_signature_t));
|
||||
if (signatures == NULL) {
|
||||
ESP_LOGE(TAG, "bootloader_mmap(0x%x, 0x%x) failed", sig_block_addr, sizeof(ets_secure_boot_signature_t));
|
||||
return ESP_FAIL;
|
||||
}
|
||||
|
||||
for (int i = 0; i < SECURE_BOOT_NUM_BLOCKS; i++) {
|
||||
const ets_secure_boot_sig_block_t *block = &signatures->block[i];
|
||||
|
||||
ret = validate_signature_block(block, i, image_digest);
|
||||
if (ret != ESP_OK) {
|
||||
ret = ESP_OK; // past the last valid signature block
|
||||
break;
|
||||
}
|
||||
|
||||
/* Generating the SHA of the public key components in the signature block */
|
||||
bootloader_sha256_handle_t sig_block_sha;
|
||||
sig_block_sha = bootloader_sha256_start();
|
||||
bootloader_sha256_data(sig_block_sha, &block->key, sizeof(block->key));
|
||||
bootloader_sha256_finish(sig_block_sha, key_digest);
|
||||
|
||||
// Check we can verify the image using this signature and this key
|
||||
uint8_t temp_verified_digest[ESP_SECURE_BOOT_DIGEST_LEN];
|
||||
bool verified = ets_rsa_pss_verify(&block->key, block->signature, image_digest, temp_verified_digest);
|
||||
|
||||
if (!verified) {
|
||||
/* We don't expect this: the signature blocks before we enable secure boot should all be verifiable or invalid,
|
||||
so this is a fatal error
|
||||
*/
|
||||
ret = ESP_FAIL;
|
||||
ESP_LOGE(TAG, "Secure boot key (%d) verification failed.", i);
|
||||
break;
|
||||
}
|
||||
ESP_LOGD(TAG, "Signature block (%d) is verified", i);
|
||||
/* Copy the key digest to the buffer provided by the caller */
|
||||
memcpy((void *)public_key_digests->key_digests[i], key_digest, ESP_SECURE_BOOT_DIGEST_LEN);
|
||||
public_key_digests->num_digests++;
|
||||
}
|
||||
|
||||
if (ret == ESP_OK && public_key_digests->num_digests > 0) {
|
||||
ESP_LOGI(TAG, "Digests successfully calculated, %d valid signatures (image offset 0x%x)",
|
||||
public_key_digests->num_digests, flash_offset);
|
||||
}
|
||||
|
||||
bootloader_munmap(signatures);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static esp_err_t check_and_generate_secure_boot_keys(const esp_image_metadata_t *image_data)
|
||||
{
|
||||
esp_err_t ret;
|
||||
/* Verify the bootloader */
|
||||
esp_image_metadata_t bootloader_data = { 0 };
|
||||
ret = esp_image_verify_bootloader_data(&bootloader_data);
|
||||
if (ret != ESP_OK) {
|
||||
ESP_LOGE(TAG, "bootloader image appears invalid! error %d", ret);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/* Check if secure boot digests are present */
|
||||
bool has_secure_boot_digest = esp_efuse_find_purpose(ESP_EFUSE_KEY_PURPOSE_SECURE_BOOT_DIGEST0, NULL);
|
||||
has_secure_boot_digest |= esp_efuse_find_purpose(ESP_EFUSE_KEY_PURPOSE_SECURE_BOOT_DIGEST1, NULL);
|
||||
has_secure_boot_digest |= esp_efuse_find_purpose(ESP_EFUSE_KEY_PURPOSE_SECURE_BOOT_DIGEST2, NULL);
|
||||
ESP_LOGI(TAG, "Secure boot digests %s", has_secure_boot_digest ? "already present":"absent, generating..");
|
||||
|
||||
if (!has_secure_boot_digest) {
|
||||
esp_image_sig_public_key_digests_t boot_key_digests = {0};
|
||||
esp_image_sig_public_key_digests_t app_key_digests = {0};
|
||||
|
||||
/* Generate the bootloader public key digests */
|
||||
ret = s_calculate_image_public_key_digests(bootloader_data.start_addr, bootloader_data.image_len - SIG_BLOCK_PADDING, &boot_key_digests);
|
||||
if (ret != ESP_OK) {
|
||||
ESP_LOGE(TAG, "Bootloader signature block is invalid");
|
||||
return ret;
|
||||
}
|
||||
|
||||
if (boot_key_digests.num_digests == 0) {
|
||||
ESP_LOGE(TAG, "No valid bootloader signature blocks found.");
|
||||
return ESP_FAIL;
|
||||
}
|
||||
ESP_LOGI(TAG, "%d signature block(s) found appended to the bootloader.", boot_key_digests.num_digests);
|
||||
|
||||
esp_efuse_purpose_t secure_boot_key_purpose[SECURE_BOOT_NUM_BLOCKS] = {
|
||||
ESP_EFUSE_KEY_PURPOSE_SECURE_BOOT_DIGEST0,
|
||||
ESP_EFUSE_KEY_PURPOSE_SECURE_BOOT_DIGEST1,
|
||||
ESP_EFUSE_KEY_PURPOSE_SECURE_BOOT_DIGEST2,
|
||||
};
|
||||
|
||||
ret = esp_efuse_write_keys(secure_boot_key_purpose, boot_key_digests.key_digests, boot_key_digests.num_digests);
|
||||
if (ret) {
|
||||
if (ret == ESP_ERR_NOT_ENOUGH_UNUSED_KEY_BLOCKS) {
|
||||
ESP_LOGE(TAG, "Bootloader signatures(%d) more than available key slots.", boot_key_digests.num_digests);
|
||||
} else {
|
||||
ESP_LOGE(TAG, "Failed to write efuse block with purpose (err=0x%x). Can't continue.", ret);
|
||||
}
|
||||
return ret;
|
||||
}
|
||||
|
||||
/* Generate the application public key digests */
|
||||
ret = s_calculate_image_public_key_digests(image_data->start_addr, image_data->image_len - SIG_BLOCK_PADDING, &app_key_digests);
|
||||
if (ret != ESP_OK) {
|
||||
ESP_LOGE(TAG, "App signature block is invalid.");
|
||||
return ret;
|
||||
}
|
||||
|
||||
if (app_key_digests.num_digests == 0) {
|
||||
ESP_LOGE(TAG, "No valid applications signature blocks found.");
|
||||
return ESP_FAIL;
|
||||
}
|
||||
|
||||
ESP_LOGI(TAG, "%d signature block(s) found appended to the app.", app_key_digests.num_digests);
|
||||
if (app_key_digests.num_digests > boot_key_digests.num_digests) {
|
||||
ESP_LOGW(TAG, "App has %d signature blocks but bootloader only has %d. Some keys missing from bootloader?");
|
||||
}
|
||||
|
||||
/* Confirm if at least one public key from the application matches a public key in the bootloader
|
||||
(Also, ensure if that public revoke bit is not set for the matched key) */
|
||||
bool match = false;
|
||||
|
||||
for (int i = 0; i < boot_key_digests.num_digests; i++) {
|
||||
|
||||
if (esp_efuse_get_digest_revoke(i)) {
|
||||
ESP_LOGI(TAG, "Key block(%d) has been revoked.", i);
|
||||
continue; // skip if the key block is revoked
|
||||
}
|
||||
|
||||
for (int j = 0; j < app_key_digests.num_digests; j++) {
|
||||
if (!memcmp(boot_key_digests.key_digests[i], app_key_digests.key_digests[j], ESP_SECURE_BOOT_DIGEST_LEN)) {
|
||||
ESP_LOGI(TAG, "Application key(%d) matches with bootloader key(%d).", j, i);
|
||||
match = true;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if (match == false) {
|
||||
ESP_LOGE(TAG, "No application key digest matches the bootloader key digest.");
|
||||
return ESP_FAIL;
|
||||
}
|
||||
|
||||
/* Revoke the empty signature blocks */
|
||||
if (boot_key_digests.num_digests < SECURE_BOOT_NUM_BLOCKS) {
|
||||
/* The revocation index can be 0, 1, 2. Bootloader count can be 1,2,3. */
|
||||
for (uint8_t i = boot_key_digests.num_digests; i < SECURE_BOOT_NUM_BLOCKS; i++) {
|
||||
ESP_LOGI(TAG, "Revoking empty key digest slot (%d)...", i);
|
||||
esp_efuse_set_digest_revoke(i);
|
||||
}
|
||||
}
|
||||
}
|
||||
return ESP_OK;
|
||||
}
|
||||
|
||||
esp_err_t esp_secure_boot_v2_permanently_enable(const esp_image_metadata_t *image_data)
|
||||
{
|
||||
ESP_LOGI(TAG, "enabling secure boot v2...");
|
||||
|
||||
if (esp_secure_boot_enabled()) {
|
||||
ESP_LOGI(TAG, "secure boot v2 is already enabled, continuing..");
|
||||
return ESP_OK;
|
||||
}
|
||||
|
||||
esp_efuse_batch_write_begin(); /* Batch all efuse writes at the end of this function */
|
||||
|
||||
esp_err_t key_state = check_and_generate_secure_boot_keys(image_data);
|
||||
if (key_state != ESP_OK) {
|
||||
esp_efuse_batch_write_cancel();
|
||||
return key_state;
|
||||
}
|
||||
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_DIS_LEGACY_SPI_BOOT);
|
||||
|
||||
esp_err_t err = ESP_FAIL;
|
||||
#ifdef CONFIG_SECURE_ENABLE_SECURE_ROM_DL_MODE
|
||||
ESP_LOGI(TAG, "Enabling Security download mode...");
|
||||
err = esp_efuse_enable_rom_secure_download_mode();
|
||||
if (err != ESP_OK) {
|
||||
ESP_LOGE(TAG, "Could not enable Security download mode...");
|
||||
return err;
|
||||
}
|
||||
#elif CONFIG_SECURE_DISABLE_ROM_DL_MODE
|
||||
ESP_LOGI(TAG, "Disable ROM Download mode...");
|
||||
err = esp_efuse_disable_rom_download_mode();
|
||||
if (err != ESP_OK) {
|
||||
ESP_LOGE(TAG, "Could not disable ROM Download mode...");
|
||||
return err;
|
||||
}
|
||||
#else
|
||||
ESP_LOGW(TAG, "UART ROM Download mode kept enabled - SECURITY COMPROMISED");
|
||||
#endif
|
||||
|
||||
#ifndef CONFIG_SECURE_BOOT_ALLOW_JTAG
|
||||
ESP_LOGI(TAG, "Disable hardware & software JTAG...");
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_DIS_PAD_JTAG);
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_DIS_USB_JTAG);
|
||||
esp_efuse_write_field_cnt(ESP_EFUSE_SOFT_DIS_JTAG, ESP_EFUSE_SOFT_DIS_JTAG[0]->bit_count);
|
||||
#else
|
||||
ESP_LOGW(TAG, "Not disabling JTAG - SECURITY COMPROMISED");
|
||||
#endif
|
||||
|
||||
#ifdef CONFIG_SECURE_BOOT_ENABLE_AGGRESSIVE_KEY_REVOKE
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_SECURE_BOOT_AGGRESSIVE_REVOKE);
|
||||
#endif
|
||||
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_SECURE_BOOT_EN);
|
||||
|
||||
err = esp_efuse_batch_write_commit();
|
||||
if (err != ESP_OK) {
|
||||
ESP_LOGE(TAG, "Error programming security eFuses (err=0x%x).", err);
|
||||
return err;
|
||||
}
|
||||
|
||||
#ifdef CONFIG_SECURE_BOOT_ENABLE_AGGRESSIVE_KEY_REVOKE
|
||||
assert(ets_efuse_secure_boot_aggressive_revoke_enabled());
|
||||
#endif
|
||||
|
||||
assert(esp_rom_efuse_is_secure_boot_enabled());
|
||||
ESP_LOGI(TAG, "Secure boot permanently enabled");
|
||||
|
||||
return ESP_OK;
|
||||
}
|
||||
@ -0,0 +1,70 @@
|
||||
/*
|
||||
* SPDX-FileCopyrightText: 2015-2021 Espressif Systems (Shanghai) CO LTD
|
||||
*
|
||||
* SPDX-License-Identifier: Apache-2.0
|
||||
*/
|
||||
|
||||
#include <strings.h>
|
||||
#include "esp_flash_encrypt.h"
|
||||
#include "esp_secure_boot.h"
|
||||
#include "esp_efuse.h"
|
||||
#include "esp_efuse_table.h"
|
||||
#include "esp_log.h"
|
||||
#include "sdkconfig.h"
|
||||
|
||||
static __attribute__((unused)) const char *TAG = "secure_boot";
|
||||
|
||||
esp_err_t esp_secure_boot_enable_secure_features(void)
|
||||
{
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_DIS_LEGACY_SPI_BOOT);
|
||||
|
||||
#ifdef CONFIG_SECURE_ENABLE_SECURE_ROM_DL_MODE
|
||||
ESP_LOGI(TAG, "Enabling Security download mode...");
|
||||
esp_err_t err = esp_efuse_enable_rom_secure_download_mode();
|
||||
if (err != ESP_OK) {
|
||||
ESP_LOGE(TAG, "Could not enable Security download mode...");
|
||||
return err;
|
||||
}
|
||||
#elif CONFIG_SECURE_DISABLE_ROM_DL_MODE
|
||||
ESP_LOGI(TAG, "Disable ROM Download mode...");
|
||||
esp_err_t err = esp_efuse_disable_rom_download_mode();
|
||||
if (err != ESP_OK) {
|
||||
ESP_LOGE(TAG, "Could not disable ROM Download mode...");
|
||||
return err;
|
||||
}
|
||||
#else
|
||||
ESP_LOGW(TAG, "UART ROM Download mode kept enabled - SECURITY COMPROMISED");
|
||||
#endif
|
||||
|
||||
#ifndef CONFIG_SECURE_BOOT_ALLOW_JTAG
|
||||
ESP_LOGI(TAG, "Disable hardware & software JTAG...");
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_DIS_PAD_JTAG);
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_DIS_USB_JTAG);
|
||||
esp_efuse_write_field_cnt(ESP_EFUSE_SOFT_DIS_JTAG, ESP_EFUSE_SOFT_DIS_JTAG[0]->bit_count);
|
||||
#else
|
||||
ESP_LOGW(TAG, "Not disabling JTAG - SECURITY COMPROMISED");
|
||||
#endif
|
||||
|
||||
#ifdef CONFIG_SECURE_BOOT_ENABLE_AGGRESSIVE_KEY_REVOKE
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_SECURE_BOOT_AGGRESSIVE_REVOKE);
|
||||
#endif
|
||||
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_SECURE_BOOT_EN);
|
||||
|
||||
#ifndef CONFIG_SECURE_BOOT_V2_ALLOW_EFUSE_RD_DIS
|
||||
bool rd_dis_now = true;
|
||||
#ifdef CONFIG_SECURE_FLASH_ENC_ENABLED
|
||||
/* If flash encryption is not enabled yet then don't read-disable efuses yet, do it later in the boot
|
||||
when Flash Encryption is being enabled */
|
||||
rd_dis_now = esp_flash_encryption_enabled();
|
||||
#endif
|
||||
if (rd_dis_now) {
|
||||
ESP_LOGI(TAG, "Prevent read disabling of additional efuses...");
|
||||
esp_efuse_write_field_bit(ESP_EFUSE_WR_DIS_RD_DIS);
|
||||
}
|
||||
#else
|
||||
ESP_LOGW(TAG, "Allowing read disabling of additional efuses - SECURITY COMPROMISED");
|
||||
#endif
|
||||
|
||||
return ESP_OK;
|
||||
}
|
||||
Loading…
x
Reference in New Issue
Block a user