This patch adds the advanced u32 match feature support with the
selection keys. It enables the users to crate a complex filter as follow
for instance:
$ tc filter add dev eth0 parent 1: prio 1 u32 match ip dport 80 0xff \
match u32 0x146ca 0xffff at 32 flowid 1:46cb
To expose TcU32Sel and TcU32Key defined in nl package, this patch copies
them to filte.go and their values that require Big-endianness are
handled appropriately in FilterAdd function in filter_linux.go.
Signed-off-by: Taku Fukushima <taku@soracom.jp>
New in kernel 4.5 is a type of qdisc for lightweight (no qdisc lock)
ingress/egress parsing, called clsact. Add support for such a qdisc
type.
One primary consumer of clsact is the bpf filter, add support for that
as well.
Current U32 filter only supports redirect action, but the U32 can
support a lot more. Refactor a bit the action generating/parsing logic
to be more generic and add BPF action support.
When creating a U32 filter, one can supply an array of Actions, which
will be executed by the U32 filter in order:
* The new MirredAction implements the same functionality as RedirIndex
field in the U32 filter, with that static field kept in the struct for
backwards compatibility.
* A new BpfAction type is added which allows a program with an open bpf
file descriptor (implementation is out of scope of this patch) to be
added as well.
Add a test for the above use case which includes one of each type of
action.
