When pushing tunnel headers, annotate skbs in the same way as tunnel
devices.
For GSO packets, the network stack requires certain fields set to
segment packets with tunnel headers. gro_gse_segment depends on
transport and inner mac header, for instance.
Add an option to pass this information.
Remove the restriction on len_diff to network header length, which
is too short, e.g., for GRE protocols.
Changes
v1->v2:
- document new flags
- BPF_F_ADJ_ROOM_MASK moved
v2->v3:
- BPF_F_ADJ_ROOM_ENCAP_L3_MASK moved
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
868d523535