Covers IPv4/VPNv4 routes with IPv6 next hop (RFC 5549), IPv6 routes with
IPv4 next hop (RFC 4798) and VPNv6 routes with IPv4 next hop (RFC 4659).
Unfortunately it also makes next hop hooks more messy.
Each BGP channel now could have two IGP tables, one for IPv4 next hops,
the other for IPv6 next hops.
Basic support for SAFI 4 and 128 (MPLS labeled IP and VPN) for IPv4 and
IPv6. Should work for route reflector, but does not properly handle
originating routes with next hop self.
Based on patches from Jan Matejka.
The patch fixes several bugs introduced in previous changes, simplifies
the protocol by handing routes uniformly, introduces asynchronous route
processing to avoid issues with separate notifications for each next-hop
in ECMP routes, and makes reconfiguration faster by avoiding quadratic
complexity.
FreeBSD 11 changed endianity of ip_len field from host order to network
order. Also DragonFly BSD allegedly expects network order here.
Thanks to Olivier Cochard-Labbé for the patch.
From now on, protocol static accepts VPN4 and VPN6 addressess.
With some concerns about VPN6 Route Distinguishers, I finally chose
to have the same format as for VPN4 (where it is defined by RFC 4364).
Anyway, Bird is now capable to insert both MPLS routes and MPLS encap
routes into kernel.
It was (among others) needed to define platform-specific AF_MPLS to 28
as this constant has been assigned in the linux kernel.
No support for BSD now, it may be added in the future.
Dropped struct mpnh and mpnh_*()
Now struct nexthop exists, nexthop_*(), and also included struct nexthop
into struct rta.
Also converted RTD_DEVICE and RTD_ROUTER to RTD_UNICAST. If it is needed
to distinguish between these two cases, RTD_DEVICE is equivalent to
IPA_ZERO(a->nh.gw), RTD_ROUTER is then IPA_NONZERO(a->nh.gw).
From now on, we also explicitely want C99 compatible compiler. We assume
that this 20-year norm should be known almost everywhere.
The variable nfa is not cleaned before each loop iteration and can have
a wrong value of nfa.nhs_reuse from the previous step.
Thanks to Bernardo Figueiredo for the bugreport and analysis.
