<filter name='no-mac-spoofing' chain='mac' priority='-800'>
  <uuid>1e9e7426-d4f1-4cb6-946c-c6e849e4653d</uuid>
  <rule action='return' direction='out' priority='500'>
    <mac srcmacaddr='$MAC'/>
  </rule>
  <rule action='drop' direction='out' priority='500'>
    <mac/>
  </rule>
</filter>

