static function prevent_image_hotlinks()
 {
     global $aio_wp_security;
     $rules = '';
     if ($aio_wp_security->configs->get_value('aiowps_prevent_hotlinking') == '1') {
         $url_string = AIOWPSecurity_Utility_Htaccess::return_regularized_url(AIOWPSEC_WP_URL);
         if ($url_string == FALSE) {
             $url_string = AIOWPSEC_WP_URL;
         }
         $rules .= AIOWPSecurity_Utility_Htaccess::$prevent_image_hotlinks_marker_start . PHP_EOL;
         //Add feature marker start
         $rules .= '<IfModule mod_rewrite.c>
                     RewriteEngine on
                     RewriteCond %{HTTP_REFERER} !^$' . PHP_EOL;
         $rules .= ' RewriteCond %{REQUEST_FILENAME} -f' . PHP_EOL;
         $rules .= ' RewriteCond %{REQUEST_FILENAME} \\.(gif|jpe?g?|png)$ [NC]' . PHP_EOL;
         $rules .= ' RewriteCond %{HTTP_REFERER} !^' . $url_string . ' [NC]' . PHP_EOL;
         $rules .= ' RewriteRule \\.(gif|jpe?g?|png)$ - [F,NC,L]
                    </IfModule>' . PHP_EOL;
         $rules .= AIOWPSecurity_Utility_Htaccess::$prevent_image_hotlinks_marker_end . PHP_EOL;
         //Add feature marker end
     }
     return $rules;
 }