controllers/Controller/Security/AuthenticationController.php
public function loginAction(Request $request, Application $app)
    {
        $options = array(
            "is_ajax" => $request->isXmlHttpRequest(),
            "error" => $app['security.last_error']($request),
            "last_username" => $app['session']->get('_security.last_username'),
            "template_assets" => $app["red_kite_cms.template_assets"],
            "twig" => $app["twig"],
            "red_kite_cms_config" => $app["red_kite_cms.configuration_handler"],
            "assets" => array(
                'getExternalStylesheets' => array(
                    $app["red_kite_cms.configuration_handler"]->webDir(
                    ) . '/components/redkitecms/twitter-bootstrap/css/bootstrap.min.css',
                    $app["red_kite_cms.configuration_handler"]->webDir() . '/sb-admin-2/css/sb-admin-2.css',
                ),
            ),
        );

        return parent::login($options);
    }
public function loginAction(Request $request, Application $app)
    {
        $options = array(
            "is_ajax" => $request->isXmlHttpRequest(),
            "error" => $app['security.last_error']($request),
            "last_username" => $app['session']->get('_security.last_username'),
            "template_assets" => $app["red_kite_cms.template_assets"],
            "twig" => $app["twig"],
            "red_kite_cms_config" => $app["red_kite_cms.configuration_handler"],
            "assets" => array(
                'getExternalStylesheets' => array(
                    $app["red_kite_cms.configuration_handler"]->webDir(
                    ) . '/components/redkitecms/twitter-bootstrap/css/bootstrap.min.css',
                    $app["red_kite_cms.configuration_handler"]->webDir() . '/sb-admin-2/css/sb-admin-2.css',
                ),
            ),
        );

        return parent::login($options);
    }
Login action

@param \Symfony\Component\HttpFoundation\Request $request
@param \Silex\Application                        $app
@return \Symfony\Component\HttpFoundation\Response