Function esp_idf_svc::sys::esp_efuse_write_keys

source · 
pub unsafe extern "C" fn esp_efuse_write_keys(
    purposes: *const u32,
    keys: *mut [u8; 32],
    number_of_keys: u32,
) -> i32
Expand description

@brief Program keys to unused efuse blocks

The burn of keys, protection bits, and purposes happens in batch mode.

@note This API also enables the read protection efuse bit for certain key blocks like XTS-AES, HMAC, ECDSA etc. This ensures that the key is only accessible to hardware peripheral.

@note For SoC’s with capability SOC_EFUSE_ECDSA_USE_HARDWARE_K (e.g., ESP32-H2), this API writes an additional efuse bit for ECDSA key purpose to enforce hardware TRNG generated k mode in the peripheral.

@param[in] purposes Array of purposes (purpose[number_of_keys]). @param[in] keys Array of keys (uint8_t keys[number_of_keys][32]). Each key is 32 bytes long. @param[in] number_of_keys The number of keys to write (up to 6 keys).

@return

  • ESP_OK: Successful.
  • ESP_ERR_INVALID_ARG: Error in the passed arguments.
  • ESP_ERR_INVALID_STATE: Error in efuses state, unused block not found.
  • ESP_ERR_NOT_ENOUGH_UNUSED_KEY_BLOCKS: Error not enough unused key blocks available
  • ESP_ERR_EFUSE_REPEATED_PROG: Error repeated programming of programmed bits is strictly forbidden.
  • ESP_ERR_CODING: Error range of data does not match the coding scheme.