librenms-librenms/html/includes/graphs/sensor/auth.inc.php

<?php

if (is_numeric($vars['id'])) {
    $sensor = dbFetchRow('SELECT * FROM sensors WHERE sensor_id = ?', array($vars['id']));

    if (is_numeric($sensor['device_id']) && ($auth || device_permitted($sensor['device_id']))) {
        $device = device_by_id_cache($sensor['device_id']);

        // This doesn't quite work for all yet.
        // $rrd_filename  = $config['rrd_dir'] . "/".$device['hostname']."/" . safename($sensor['sensor_class']."-" . $sensor['sensor_type'] . "-".$sensor['sensor_index'].".rrd");
        $rrd_filename = get_sensor_rrd($device, $sensor);

        $title  = generate_device_link($device);
        $title .= ' :: Sensor :: '.htmlentities($sensor['sensor_descr']);
        $auth   = true;
    }
}