IFE action in tc(8)		     Linux		   IFE action in tc(8)



NAME
       IFE - encapsulate/decapsulate metadata

SYNOPSIS
       tc ...  action ife DIRECTION [ ACTION ]	[ dst DMAC ]  [ src SMAC ]  [
	       type TYPE ]  [  CONTROL ]  [ index INDEX ]

       DIRECTION := {  decode | encode }

       ACTION := {  allow ATTR | use ATTR value }

       ATTR := {  mark | prio | tcindex }

       CONTROL := {  reclassify | use | pipe | drop | continue | ok | goto
	       chain CHAIN_INDEX }

DESCRIPTION
       The ife action allows for a sending side to encapsulate arbitrary
       metadata, which is then decapsulated by the receiving end. The sender
       runs in encoding mode and the receiver in decode mode. Both sender and
       receiver must specify the same ethertype. In the future, a registered
       ethertype may be available as a default.

OPTIONS
       decode For the receiving side; decode the metadata if the packet
	      matches.

       encode For the sending side. Encode the specified metadata if the
	      packet matches.

       allow  Encode direction only. Allows encoding specified metadata.

       use    Encode direction only. Enforce static encoding of specified
	      metadata.

       mark [
	      u32_value ] The value to set for the skb mark. The u32 value is
	      required only when use is specified. If mark value is zero, it
	      will not be encoded, instead "overlimits" statistics increment
	      and CONTROL action is taken.

       prio [
	      u32_value ] The value to set for priority in the skb structure.
	      The u32 value is required only when use is specified.

       tcindex [
	      u16_value ] Value to set for the traffic control index in the
	      skb structure. The u16 value is required only when use is
	      specified.

       dmac DMAC
       smac SMAC
	      Optional six byte destination or source MAC address to encode.

       type TYPE
	      Optional 16-bit ethertype to encode. If not specified value of
	      0xED3E will be used.

       CONTROL
	      Action to take following an encode/decode.

       index INDEX
	      Assign a unique ID to this action instead of letting the kernel
	      choose one automatically.	 INDEX is a 32bit unsigned integer
	      greater than zero.

EXAMPLES
       On the receiving side, match packets with ethertype 0xdead and restart
       classification so that it will match ICMP on the next rule, at prio 3:
	      # tc qdisc add dev eth0 handle ffff: ingress
	      # tc filter add dev eth0 parent ffff: prio 2 protocol 0xdead \
		   u32 match u32 0 0 flowid 1:1 \
		   action ife decode reclassify
	      # tc filter add dev eth0 parent ffff: prio 3 protocol ip \
		   u32 match ip protocol 0xff flowid 1:1 \
		   action continue

       Match with skb mark of 17:

	      # tc filter add dev eth0 parent ffff: prio 4 protocol ip \
		   handle 0x11 fw flowid 1:1 \
		   action ok

       Configure the sending side to encode for the filters above. Use a
       destination IP address of 192.168.122.237/24, then tag with skb mark of
       decimal 17. Encode the packet with ethertype 0xdead, add skb->mark to
       allowed list of meta datum to send, and rewrite the destination MAC
       address to 02:15:15:15:15:15.

	      # tc qdisc add dev eth0 root handle 1: prio
	      # tc filter add dev eth0 parent 1: protocol ip prio 10 u32 \
		   match ip dst 192.168.122.237/24 \
		   match ip protocol 1 0xff \
		   flowid 1:2 \
		   action skbedit mark 17 \
		   action ife encode \
		   type 0xDEAD \
		   allow mark \
		   dst 02:15:15:15:15:15


SEE ALSO
       tc(8), tc-u32(8)

iproute2			  22 Apr 2016		   IFE action in tc(8)