Qemu currently sends an Ethernet packet with protocol id 0x835 once a VM was successfully migrated. The content of the packet looks like a gratuitous RARP, just with the wrong protocol ID, which should be 0x8035. I wrote some filters to let either one of the packets pass and am adapting the clean-traffic sample filter to use it. I am also doing some changes on the existing ARP filter which was lacking a test for source MAC address. Signed-off-by: Stefan Berger <stefanb(a)us.ibm.com&gt; --- examples/xml/nwfilter/Makefile.am | 5 ++++- examples/xml/nwfilter/clean-traffic.xml | 3 +++ examples/xml/nwfilter/no-arp-spoofing.xml | 13 ++++++++----- examples/xml/nwfilter/no-other-rarp-traffic.xml | 4 ++++ examples/xml/nwfilter/qemu-announce-self-rarp.xml | 14 ++++++++++++++ examples/xml/nwfilter/qemu-announce-self.xml | 13 +++++++++++++ 6 files changed, 46 insertions(+), 6 deletions(-) Index: libvirt-acl/examples/xml/nwfilter/Makefile.am =================================================================== --- libvirt-acl.orig/examples/xml/nwfilter/Makefile.am +++ libvirt-acl/examples/xml/nwfilter/Makefile.am @@ -11,7 +11,10 @@ FILTERS = \ no-ip-spoofing.xml \ no-mac-broadcast.xml \ no-mac-spoofing.xml \ - no-other-l2-traffic.xml + no-other-l2-traffic.xml \ + no-other-rarp-traffic.xml \ + qemu-announce-self.xml \ + qemu-announce-self-rarp.xml EXTRA_DIST=$(FILTERS) Index: libvirt-acl/examples/xml/nwfilter/qemu-announce-self-rarp.xml =================================================================== --- /dev/null +++ libvirt-acl/examples/xml/nwfilter/qemu-announce-self-rarp.xml @@ -0,0 +1,14 @@ +<filter name='qemu-announce-self-rarp' chain='rarp'> + <rule action='accept' direction='out' priority='500'> + <rarp opcode='Request_Reverse' + srcmacaddr='$MAC' dstmacaddr='ff:ff:ff:ff:ff:ff' + arpsrcmacaddr='$MAC' arpdstmacaddr='$MAC' + arpsrcipaddr='0.0.0.0' arpdstipaddr='0.0.0.0'/> + </rule> + <rule action='accept' direction='in' priority='500'> + <rarp opcode='Request_Reverse' + dstmacaddr='ff:ff:ff:ff:ff:ff' + arpsrcmacaddr='$MAC' arpdstmacaddr='$MAC' + arpsrcipaddr='0.0.0.0' arpdstipaddr='0.0.0.0'/> + </rule> +</filter> Index: libvirt-acl/examples/xml/nwfilter/clean-traffic.xml =================================================================== --- libvirt-acl.orig/examples/xml/nwfilter/clean-traffic.xml +++ libvirt-acl/examples/xml/nwfilter/clean-traffic.xml @@ -14,4 +14,7 @@ <!-- preventing any other traffic than IPv4 and ARP --> <filterref filter='no-other-l2-traffic'/> + <!-- allow qemu to send a self-announce upon migration end --> + <filterref filter='qemu-announce-self'/> + </filter> Index: libvirt-acl/examples/xml/nwfilter/no-arp-spoofing.xml =================================================================== --- libvirt-acl.orig/examples/xml/nwfilter/no-arp-spoofing.xml +++ libvirt-acl/examples/xml/nwfilter/no-arp-spoofing.xml @@ -1,27 +1,30 @@ <filter name='no-arp-spoofing' chain='arp'> <uuid>f88f1932-debf-4aa1-9fbe-f10d3aa4bc95</uuid> + <rule action='drop' direction='out' priority='300' > + <mac match='no' srcmacaddr='$MAC'/> + </rule> <!-- no arp spoofing --> <!-- drop if ipaddr or macaddr does not belong to guest --> - <rule action='drop' direction='out' priority='400' > + <rule action='drop' direction='out' priority='350' > <arp match='no' arpsrcmacaddr='$MAC'/> </rule> <rule action='drop' direction='out' priority='400' > <arp match='no' arpsrcipaddr='$IP' /> </rule> <!-- drop if ipaddr or macaddr odes not belong to guest --> - <rule action='drop' direction='in' priority='400' > + <rule action='drop' direction='in' priority='450' > <arp match='no' arpdstmacaddr='$MAC'/> <arp opcode='reply'/> </rule> - <rule action='drop' direction='in' priority='400' > + <rule action='drop' direction='in' priority='500' > <arp match='no' arpdstipaddr='$IP' /> </rule> <!-- accept only request or reply packets --> - <rule action='accept' direction='inout' priority='500' > + <rule action='accept' direction='inout' priority='600' > <arp opcode='request'/> </rule> - <rule action='accept' direction='inout' priority='500' > + <rule action='accept' direction='inout' priority='650' > <arp opcode='reply'/> </rule> <!-- drop everything else --> Index: libvirt-acl/examples/xml/nwfilter/no-other-rarp-traffic.xml =================================================================== --- /dev/null +++ libvirt-acl/examples/xml/nwfilter/no-other-rarp-traffic.xml @@ -0,0 +1,4 @@ +<filter name='no-other-rarp-traffic' chain='rarp'> + <rule action='drop' direction='inout' priority='1000'/> +</filter> + Index: libvirt-acl/examples/xml/nwfilter/qemu-announce-self.xml =================================================================== --- /dev/null +++ libvirt-acl/examples/xml/nwfilter/qemu-announce-self.xml @@ -0,0 +1,13 @@ +<filter name='qemu-announce-self' chain='root'> + <!-- as of 4/26/2010 qemu sends out a bogus packet with + wrong rarp protocol ID --> + <!-- accept what is being sent now --> + <rule action='accept' direction='out'> + <mac protocolid='0x835'/> + </rule> + + <!-- accept if it was changed to rarp --> + <filterref filter='qemu-announce-self-rarp'/> + <filterref filter='no-other-rarp-traffic'/> + +</filter>