<filter name='testcase'>
    <uuid>f4b3f745-d23d-2ee6-218a-d5671611229b</uuid>
    <!-- allow incoming ICMP Echo Reply -->
    <rule action='accept' direction='in' priority='500'>
        <icmp type='0'/>
    </rule>
    <!-- allow outgoing ICMP Echo Request -->
    <rule action='accept' direction='out' priority='500'>
        <icmp type='8'/>
    </rule>
    <!-- drop all other ICMP traffic -->
    <rule action='drop' direction='inout' priority='600'>
        <icmp/>
    </rule>
</filter>