chrome.networking.config

Implementing a Captive Portal Authenticator

1. Using setNetworkFilter, the Extension registers for a list of Wi-Fi networks that it wants to handle captive portals on.
2. If one of these networks is detected by Chrome, it will appear in the network list, badged with an icon to indicate that a captive portal handler is available.

   

3. If the user selects such a network, but a captive portal is not detected, Chrome will connect as usual - the Extension will never be involved.
4. Otherwise, if a captive portal is detected, the user is notified and asked to authenticate using the registered Extension or whether to visit the captive portal page.

   

5. If the user selects the Extension, Chrome notifies the Extension through the onCaptivePortalDetected event.
6. The Extension should now interact with the user if necessary and authenticate at the captive portal.
7. Once the Extension finished the authentication, it notifies the API using finishAuthentication about its success or failure.

In the Extension, this can look similar to the following snippet:

      var myNetworks = [
        { Type: 'WiFi', SSID: 'MyHotSpot-1' },
        { Type: 'WiFi', SSID: 'MyHotSpot-2' }
      ];
      
      chrome.networking.config.setNetworkFilter(myNetworks, function() {
          if (chrome.runtime.lastError) {
              // Handle Error
          }
      });
      
      chrome.networking.config.onCaptivePortalDetected.addListener(
        function(networkInfo) {
          var guid = networkInfo.GUID;
      
          // Check at first whether we really care about this network.
          // This can look at additional network properties like BSSID that are not
          // supported in the filter.
          if (isBadNetwork(networkInfo)) {
            chrome.networking.config.finishAuthentication(guid, 'unhandled');
            return;
          }
          checkForMyCaptivePortalServer(function(serverStatus) {
            if (serverStatus == 'not-detected') {
              chrome.networking.config.finishAuthentication(guid, 'unhandled');
              return;
            }
            if (serverStatus == 'error') {
              chrome.networking.config.finishAuthentication(guid, 'failed');
              return;
            }
      
            // If required, interact with the user, e.g. for registration on first
            // usage. Credentials can be cached for subsequent authentications.
            ShowUIToRegisterUser(continueAuthentication.bind(null, guid));
          });
      });
      
      function continueAuthentication(guid, credentials) {
        if (!credentials) {
          chrome.networking.config.finishAuthentication(guid, 'failed');
        }
        AuthenticateToMyCaptivePortalServer(credentials, function(success) {
          chrome.networking.config.finishAuthentication(
              guid, success ? 'succeeded' : 'rejected');
        });
      }
      

Summary