Random Hardware Unique Key

This sample writes random hardware unique keys (HUKs) to the Key Management Unit (KMU), when available, or to the relevant flash memory page, when the KMU is not present.

Overview

When using the Hardware unique key library together with the nRF Secure Immutable Bootloader, you must provision a hardware unique key for the bootloader into the relevant KMU slot or flash memory page.

To provision the HUKs, build and run this sample before programming the bootloader and application. It will save the HUKs in the device.

Requirements

The sample supports the following development kits:

Hardware platforms

PCA

Board name

Build target

nRF5340 DK

PCA10095

nrf5340dk_nrf5340

nrf5340dk_nrf5340_cpuapp

nRF9160 DK

PCA10090

nrf9160dk_nrf9160

nrf9160dk_nrf9160

nRF52840 DK

PCA10056

nrf52840dk_nrf52840

nrf52840dk_nrf52840

Building and Running

This sample can be found under samples/keys/random_hw_unique_key in the nRF Connect SDK folder structure.

See Building and programming a sample application for information about how to build and program the application.

Testing

After programming the sample to your development kit, test it by performing the following steps:

  1. Connect to the kit that runs this sample with a terminal emulator (for example, PuTTY). See How to connect with PuTTY for the required settings.

  2. Reset the kit.

  3. Observe that the following output:

    Writing random keys to KMU.
Success!

    If an error occurs, the sample will print a message and it will raise a kernel panic.

Dependencies

This sample uses the following libraries: