bool esp32_fs_crypt_init(void) {
uint8_t tmp[32];
uint32_t addr = 0;
for (addr = 0; addr < spi_flash_get_chip_size(); addr += 32) {
mgos_wdt_feed();
if (spi_flash_read(addr, tmp, sizeof(tmp)) != ESP_OK) {
LOG(LL_ERROR, ("SPI read error at 0x%x", addr));
return false;
}
int j;
for (j = 0; j < sizeof(tmp); j++) {
if (tmp[j] != 0xff) break;
}
if (j < sizeof(tmp)) continue;
/* Found a suitably empty location, now decrypt it. */
if (spi_flash_read_encrypted(addr, tmp, sizeof(tmp)) != ESP_OK) {
LOG(LL_ERROR, ("SPI encrypted read error at 0x%x", addr));
return false;
}
/* Now in tmp we have 32 x 0xff processed with the flash encryption key. */
mbedtls_aes_init(&s_aes_ctx_enc);
mbedtls_aes_setkey_enc(&s_aes_ctx_enc, tmp, 256);
mbedtls_aes_init(&s_aes_ctx_dec);
mbedtls_aes_setkey_dec(&s_aes_ctx_dec, tmp, 256);
LOG(LL_INFO, ("FS encryption key set up, seed @ 0x%x", addr));
return true;
}
LOG(LL_ERROR, ("Could not a suitable seed area for FS encryption"));
return false;
}
esp_err_t IRAM_ATTR spi_flash_erase_range(uint32_t start_addr, uint32_t size)
{
CHECK_WRITE_ADDRESS(start_addr, size);
if (start_addr % SPI_FLASH_SEC_SIZE != 0) {
return ESP_ERR_INVALID_ARG;
}
if (size % SPI_FLASH_SEC_SIZE != 0) {
return ESP_ERR_INVALID_SIZE;
}
if (size + start_addr > spi_flash_get_chip_size()) {
return ESP_ERR_INVALID_SIZE;
}
size_t start = start_addr / SPI_FLASH_SEC_SIZE;
size_t end = start + size / SPI_FLASH_SEC_SIZE;
const size_t sectors_per_block = BLOCK_ERASE_SIZE / SPI_FLASH_SEC_SIZE;
COUNTER_START();
esp_rom_spiflash_result_t rc;
rc = spi_flash_unlock();
if (rc == ESP_ROM_SPIFLASH_RESULT_OK) {
for (size_t sector = start; sector != end && rc == ESP_ROM_SPIFLASH_RESULT_OK; ) {
spi_flash_guard_start();
if (sector % sectors_per_block == 0 && end - sector > sectors_per_block) {
rc = esp_rom_spiflash_erase_block(sector / sectors_per_block);
sector += sectors_per_block;
COUNTER_ADD_BYTES(erase, sectors_per_block * SPI_FLASH_SEC_SIZE);
} else {
rc = esp_rom_spiflash_erase_sector(sector);
++sector;
COUNTER_ADD_BYTES(erase, SPI_FLASH_SEC_SIZE);
}
spi_flash_guard_end();
}
}
COUNTER_STOP(erase);
return spi_flash_translate_rc(rc);
}
