Re: [PATCH net-next V2 0/3] net/sched: act_pedit: Use offset relative to conventional network headers

On Thu,  5 Jan 2017 11:54:51 +0200, Amir Vadai wrote:

You asked me [1] why did I use specific header names instead of layers (L2, L3...),
and I explained that it is on purpose, this extra information is planned to be used
by hardware drivers to offload the action.

Some FW/HW parser APIs are such that they need to get the specific header type (e.g
IPV4 or IPV6, TCP or UDP) and not only the networking level (e.g network or transport).

Don't we need better API specification (and enforcement) then, though?
See below.

Usage example:
$ tc filter add dev enp0s9 protocol ip parent ffff: \
   flower \
     ip_proto tcp \
    dst_port 80 \
   action \
       pedit munge ip ttl add 0xff \
       pedit munge tcp dport set 8080 \
     pipe action mirred egress redirect dev veth0

What happens when one does:

tc filter add ... flower ip_proto udp action pedit munge tcp ...

?

 Jiri