tag:
priority: 310 # before real devices that redirect
type: txt
help: Input functional block (IFB) interface name
val_help: <ifbN>; Input functional block interface name

syntax:expression: pattern $VAR(@) "^ifb[0-9]+$" ; "name must be (ifb0-ifb999)"

begin: [ -d /sys/module/ifb ] || sudo modprobe ifb numifbs=0
create:	ip link add $VAR(@) type ifb && ip link set $VAR(@) up
delete: ip link delete dev $VAR(@)