Merge r280955
Preserve IPv6 fragment IDs accross reassembly and refragmentation
When forwarding fragmented IPv6 packets and filtering with PF we
reassemble and refragment. That means we generate new fragment headers
and a new fragment ID.
We already save the fragment IDs so we can do the reassembly so it's
straightforward to apply the incoming fragment ID on the refragmented
packets.
Differential Revision: https://reviews.freebsd.org/D2817
Reviewed by: gnn
git-svn-id: svn://svn.freebsd.org/base/stable/10@284572
ccf9f872-aa2e-dd11-9fc8-
001c23d0bc1f