Wi-Fi credentials

The Wi-Fi credentials library provides means to load and store Wi-Fi network credentials.

Overview

This library uses either Zephyr’s settings subsystem or Platform Security Architecture (PSA) Internal Trusted Storage (ITS) to store credentials. It also holds a list of SSIDs in RAM to provide dictionary-like access using SSIDs as keys.

Configuration

To use the Wi-Fi credentials library, enable the CONFIG_WIFI_CREDENTIALS Kconfig option.

You can pick the backend using the following options:

To configure the maximum number of networks, use the CONFIG_WIFI_CREDENTIALS_MAX_ENTRIES Kconfig option.

The IEEE 802.11 standard does not specify the maximum length of SAE passwords. To change the default, use the CONFIG_WIFI_CREDENTIALS_SAE_PASSWORD_LENGTH Kconfig option.

When using the PSA ITS backend, entries will be saved under consecutive key IDs with an offset configured with the CONFIG_WIFI_CREDENTIALS_BACKEND_PSA_OFFSET Kconfig option.

Adding credentials

You can add credentials using the wifi_credentials_set_personal() and wifi_credentials_set_personal_struct() functions. The former will build the internally used struct from given fields, while the latter takes the struct directly. If you add credentials with the same SSID twice, the older entry will be overwritten.

Querying credentials

With an SSID, you can query credentials using the wifi_credentials_get_by_ssid_personal() and wifi_credentials_get_by_ssid_personal_struct() functions.

You can iterate over all stored credentials with the wifi_credentials_for_each_ssid() function. Deleting or overwriting credentials while iterating is allowed, since these operations do not change internal indices.

Removing credentials

You can remove credentials using the wifi_credentials_delete_by_ssid() function.

Limitations

The library has the following limitations:

  • Although permitted by the IEEE 802.11 standard, this library does not support zero-length SSIDs.

  • Wi-Fi Protected Access (WPA) Enterprise credentials are not yet supported.

  • The number of networks stored is fixed compile time.

API documentation

Header file: include/net/wifi_credentials.h
Source files: subsys/net/lib/wifi_credentials
Wi-Fi credentials library