Using wpa_supplicant to manage your Wi-Fi network connections

The wpa_supplicant daemon is the “standard” mechanism used to provide persistence of Wi-Fi networking information and to manage automated connections into networks without user intervention.

The WPA supplicant shipped with QNX Neutrino is based on the open-source supplicant located at http://hostap.epitest.fi/wpa_supplicant/.

In order to support wireless connectivity, the supplicant:

• provides a consistent interface for configuring all authentication and encryption mechanisms (unsecure, WEP, WPA, WPA2, and WPA3)
• supports configuration of ad hoc and infrastructure modes of operation
• maintains the network configuration information in a configuration file (by default /etc/wpa_supplicant.conf)
• provides auto-connectivity capability, allowing a client to connect to a WAP without user intervention

A sample wpa_supplicant.conf file is installed in /etc for you. It contains a detailed description of the basic supplicant configuration parameters, network parameter descriptions (and there are lots of them), and sample network configuration blocks.

There is a command-line configuration tool called wpa_cli, which works with the WPA supplicant. This tool lets you query the stack for information on Wi-Fi networks, as well as update the configuration file dynamically.

If you want wpa_cli to be capable of updating the wpa_supplicant.conf file, edit the file by uncommenting the update_config=1 option. Note that when wpa_cli rewrites the configuration file, it strips all of the comments. Copy the file into /etc and make sure that root owns it and is the only user who can read or write it, because it contains clear-text keys and password information.