Bluetooth LE passkey module

Use the Bluetooth® LE passkey module to enable pairing based on passkey for increased security.

Note

This module is part of the full nRF Desktop design, but none of the reference board configurations currently maintained in the repository enable it. The module remains in the codebase and you can enable it using a Kconfig option in a custom configuration.

Module events

Source Module	Input Event	This Module	Output Event	Sink Module
Source modules for module_state_event	module_state_event	ble_passkey
Passkey module	passkey_input_event
			module_state_event	Sink modules for module_state_event
			passkey_req_event	Passkey module

Note

See the Application overview for more information about the event-based communication in the nRF Desktop application and about how to read this table.

Configuration

The module requires the basic Bluetooth configuration, as described in nRF Desktop: Bluetooth. The module can be used only for nRF Desktop Bluetooth Peripheral devices (CONFIG_DESKTOP_BT_PERIPHERAL).

Use the option CONFIG_DESKTOP_BLE_ENABLE_PASSKEY to enable the module. Make sure to enable and configure the Passkey module if you decide to use this option.

Implementation details

The Bluetooth LE passkey module is used only by Bluetooth Peripheral devices.

Passkey enabled

The Bluetooth LE passkey module registers the set of authenticated pairing callbacks (bt_conn_auth_cb). The callbacks can be used to achieve higher security levels. The passkey input is handled in the Passkey module.

Note

By default, Zephyr’s Bluetooth Peripheral demands the security level 3 in case the passkey authentication is enabled. If the nRF Desktop dongle cannot achieve the security level 3, it cannot connect with the peripheral. The CONFIG_BT_SMP_ENFORCE_MITM option is disabled by default to allow the dongle to connect without the authentication.