The old code stored route verdicts and temporary routes directly in
rtable. The new code do not store received routes (it immediately
compares them with exported routes and resolves conflicts) and uses
internal bitmap to keep track of which routes were received and which
needs to be reinstalled.

By not putting 'invalid' temporary routes to rtable, we keep rtable
in consistent state, therefore scan no longer needs to be atomic
operation and could be splitted to multiple events.

This is still OK for everybody to fit into RAM and also probably enough
to keep a little collision rate for full BGP table.

This patch adds support for source-specific IPv6 routes to BIRD core.
This is based on Dean Luga's original patch, with the review comments
addressed. SADR support is added to network address parsing in confbase.Y
and to the kernel protocol on Linux.

Currently there is no way to mix source-specific and non-source-specific
routes (i.e., SADR tables cannot be connected to non-SADR tables).

Thanks to Toke Hoiland-Jorgensen for the original patch.
Minor changes by Ondrej Santiago Zajicek.

Add flow4/flow6 network and rt-table type and operations, config grammar
and static protocol support.

Squashed flowspec branch from Pavel Tvrdik.

Thanks to Ondrej Zajicek for his support with writing this code.

Returned user data pointers have offset relative to fib_node.

New data types net_addr and variants (in lib/net.h) describing
network addresses (prefix/pxlen). Modifications of FIB structures
to handle these data types and changing everything to use these
data types instead of prefix/pxlen pairs where possible.

The commit is WiP, some protocols are not yet updated (BGP, Kernel),
and the code contains some temporary scaffolding.

Comments are welcome.

The new RIP implementation fixes plenty of old bugs and also adds support
for many new features: ECMP support, link state support, BFD support,
configurable split horizon and more. Most options are now per-interface.

I've changed the init callback type to a typedef to work around a bug
in kernel-doc I'm too lazy to hunt now.

routing in a FIB.

by a lightning :)

and other non-portable functions on all systems.

several debug() calls converted to DBG().

compile :-(.

This is implemented in a way similar to lib/slists.h, but it took some
more effort to make rehashing not disturb the readers. We do it by just
taking _highest_ k bits of ipa_hash as our hash value and sorting each
box by whole ipa_hash().

Consult FIB_ITERATE_* macros in nest/route.h.

Implemented fib_check() debugging function and also rewrote the rehashing
algorithm to use better thresholds and not to waste time by rehashing
forth and back.

names and include files.

o  struct network: FIB flags used for kernel syncing.
o  struct network: `next' field deleted (historical relic).

complete now.