Wi-Fi Easy Connect^TM (DPP)

Wi-Fi Easy Connect^TM, also known as Device Provisioning Protocol (DPP) or Easy Connect, is a provisioning protocol certified by Wi-Fi Alliance. It is a secure and standardized provisioning protocol for configuration of Wi-Fi Devices. With Easy Connect adding a new device to a network is as simple as scanning a QR Code. This reduces complexity and enhances user experience while onboarding devices without UI like Smart Home and IoT products. Unlike old protocols like WiFi Protected Setup (WPS), Wi-Fi Easy Connect incorporates strong encryption through public key cryptography to ensure networks remain secure as new devices are added. Easy Connect brings many benefits in the User Experience:

Simple and intuitive to use; no lengthy instructions to follow for new device setup

No need to remember and enter passwords into the device being provisioned

Works with electronic or printed QR codes, or human-readable strings

Supports both WPA2 and WPA3 networks

Please refer to Wi-Fi Alliance's official page on Easy Connect for more information.

ESP32-C2 supports Enrollee mode of Easy Connect with QR Code as the provisioning method. A display is required to display this QR Code. Users can scan this QR Code using their capable device and provision the ESP32-C2 to their Wi-Fi network. The provisioning device needs to be connected to the AP which need not support Wi-Fi Easy Connect™. Easy Connect is still an evolving protocol. Of known platforms that support the QR Code method are some Android smartphones with Android 10 or higher. To use Easy Connect no additional App needs to be installed on the supported smartphone.

Application Example

Example on how to provision ESP32-C2 using a supported smartphone: wifi/wifi_easy_connect/dpp-enrollee.

API Reference

Header File

components/wpa_supplicant/esp_supplicant/include/esp_dpp.h

Functions

esp_err_t esp_supp_dpp_init(esp_supp_dpp_event_cb_t evt_cb)

Initialize DPP Supplicant.

   Starts DPP Supplicant and initializes related Data Structures.

return

ESP_OK: Success
ESP_FAIL: Failure

Parameters: evt_cb -- Callback function to receive DPP related events

void esp_supp_dpp_deinit(void)

De-initalize DPP Supplicant.

   Frees memory from DPP Supplicant Data Structures.

esp_err_t esp_supp_dpp_bootstrap_gen(const char *chan_list, esp_supp_dpp_bootstrap_t type, const char *key, const char *info)

Generates Bootstrap Information as an Enrollee.

   Generates Out Of Band Bootstrap information as an Enrollee which can be
   used by a DPP Configurator to provision the Enrollee.

Parameters

chan_list -- List of channels device will be available on for listening
type -- Bootstrap method type, only QR Code method is supported for now.
key -- (Optional) 32 byte Raw Private Key for generating a Bootstrapping Public Key
info -- (Optional) Ancilliary Device Information like Serial Number

Returns

ESP_OK: Success
ESP_FAIL: Failure

esp_err_t esp_supp_dpp_start_listen(void)

Start listening on Channels provided during esp_supp_dpp_bootstrap_gen.

   Listens on every Channel from Channel List for a pre-defined wait time.

Returns

ESP_OK: Success
ESP_FAIL: Generic Failure
ESP_ERR_INVALID_STATE: ROC attempted before WiFi is started
ESP_ERR_NO_MEM: Memory allocation failed while posting ROC request

void esp_supp_dpp_stop_listen(void)

Stop listening on Channels.

   Stops listening on Channels and cancels ongoing listen operation.

Macros

ESP_DPP_AUTH_TIMEOUT_SECS

ESP_ERR_DPP_FAILURE: Generic failure during DPP Operation

ESP_ERR_DPP_TX_FAILURE: DPP Frame Tx failed OR not Acked

ESP_ERR_DPP_INVALID_ATTR: Encountered invalid DPP Attribute

ESP_ERR_DPP_AUTH_TIMEOUT: DPP Auth response was not recieved in time

Type Definitions

typedef enum dpp_bootstrap_type esp_supp_dpp_bootstrap_t: Types of Bootstrap Methods for DPP.

typedef void (*esp_supp_dpp_event_cb_t)(esp_supp_dpp_event_t evt, void *data)

Callback function for receiving DPP Events from Supplicant.

   Callback function will be called with DPP related information.

Param evt: DPP event ID
Param data: Event data payload

Enumerations

enum dpp_bootstrap_type

Types of Bootstrap Methods for DPP.

Values:

enumerator DPP_BOOTSTRAP_QR_CODE: QR Code Method

enumerator DPP_BOOTSTRAP_PKEX: Proof of Knowledge Method

enumerator DPP_BOOTSTRAP_NFC_URI: NFC URI record Method

enum esp_supp_dpp_event_t

Types of Callback Events received from DPP Supplicant.