RFC 5549?

[Donald Sharp]

All -

The FRRouting project has some basic support for rfc 5549 and I've
been asked to see if it is possible to get this bit of code working
with the FRRouting freebsd kernel interface.  What is RFC 5549 you
ask?  The tl;dr of it is that you have v4 prefixes w/ a v6 gateway.
For some more background the linux implementation cheats ( and I would
like to emphatically point out that I'm not suggesting this solution,
I'm giving the linux solution to the problem as a data point to how it
was solved in one instance ) by installing a neighbor entry for
`169.254.0.1 <outgoing interface> <mac address on the other side>` and
when installing the v4 prefix we see the v6 nexthop and replace it
with `169.254.0.1 <outgoing interface>` in the netlink message to the
kernel.  Is support of RFC 5549 possible in Freebsd?

thanks!

donald