Add a new protocol offering route aggregation.
User can specify list of route attributes in the configuration file and
run route aggregation on the export side of the pipe protocol. Routes are
sorted and for every group of equivalent routes new route is created and
exported to the routing table. It is also possible to specify filter
which will run for every route before aggregation.
Furthermore, it will be possible to set attributes of new routes
according to attributes of the aggregated routes.
This is a work in progress.
Original work by Igor Putovny, subsequent cleanups and finalization by
Maria Matejka.
This is a split-commit of the neighboring aggregator branch
with a bit improved lvalue handling, to have easier merge into v3.
Some [redacted] (yes, myself) had a really bad idea
to rename nest/route.h to nest/rt.h while refactoring
some data structures out of it.
This led to unnecessarily complex problems with
merging updates from v2. Reverting this change
to make my life a bit easier.
At least it needed only one find-sed command:
find -name '*.[chlY]' -type f -exec sed -i 's#nest/rt.h#nest/route.h#' '{}' +
This merge was particularly difficult. I finally resorted to delete the
symbol scope active flag altogether and replace its usage by other
means.
Also I had to update custom route attribute registration to fit
both the scope updates in v2 and the data model in v3.
Conflicts:
conf/cf-lex.l
conf/conf.h
conf/confbase.Y
conf/gen_keywords.m4
conf/gen_parser.m4
filter/config.Y
nest/config.Y
proto/bgp/config.Y
proto/static/config.Y
Keywords and attributes are split to separate namespaces, to avoid
collisions between regular keyword use and attribute overlay.
There are now 3 different pools with specific lifetime. All of these are
available since protocol start, anyway they get freed in different
moments.
First, pool_up gets freed immediately after announcing PS_STOP, to e.g.
stop all timers and events regularly updating the routing table when the
imports are already flushing.
Then, pool_inloop gets freed just before the protocol loop is finally
stopped, after all channels, imports and exports and other hooks are
cleaned up.
And finally, the pool itself is freed the last. Unless you explicitly
need the early free, use this pool.
Old configs do not define MPLS domains and may use a static protocol
to define static MPLS routes.
When MPLS channel is the only channel of static protocol, handle it
as a main channel. Also, define implicit MPLS domain if needed and
none is defined.
Use mpls_new_label() / mpls_free_label() also for static labels, to keep
track of allocated labels and to enforce label ranges.
Static label allocations always use static label range, regardless of
configured label range.
Instead of just using route attributes, static routes with
static MPLS labels can be defined just by e.g.:
route 10.1.1.0/24 mpls 100 via 10.1.2.1 mpls 200;
The L3VPN protocol implements RFC 4364 BGP/MPLS VPNs using MPLS backbone.
It works similarly to pipe. It connects IP table (one per VRF) with (global)
VPN table. Routes passed from VPN table to IP table are stripped of RD and
filtered by import targets, routes passed in the other direction are extended
with RD, MPLS labels and export targets in extended communities. A separate
MPLS channel is used to announce MPLS routes for the labels.
The new labeling policy MPLS_POLICY_VRF assigns one label to all routes
(from the same FEC map associated with one VRF), while replaces their
next hops with a lookup to a VRF table. This is useful for L3VPN
protocol.
The MPLS subsystem manages MPLS labels and handles their allocation to
MPLS-aware routing protocols. These labels are then attached to IP or VPN
routes representing label switched paths -- LSPs.
There was already a preliminary MPLS support consisting of MPLS label
net_addr, MPLS routing tables with static MPLS routes, remote labels in
next hops, and kernel protocol support.
This patch adds the MPLS domain as a basic structure representing local
label space with dynamic label allocator and configurable label ranges.
To represent LSPs, allocated local labels can be attached as route
attributes to IP or VPN routes with local labels as attributes.
There are several steps for handling LSP routes in routing protocols --
deciding to which forwarding equivalence class (FEC) the LSP route
belongs, allocating labels for new FECs, announcing MPLS routes for new
FECs, attaching labels to LSP routes. The FEC map structure implements
basic code for managing FECs in routing protocols, therefore existing
protocols can be made MPLS-aware by adding FEC map and delegating
most work related to local label management to it.
If the protocol supports route refresh on export, we keep the stop-start
method of route refeed. This applies for BGP with ERR or with export
table on, for OSPF, Babel, RIP or Pipe.
For BGP without ERR or for future selective ROA reloads, we're adding an
auxiliary export request, doing the refeed while the main export request
is running, somehow resembling the original method of BIRD 2 refeed.
There is also a refeed request queue to keep track of different refeed
requests.
In general, private_id is sparse and protocols may want to map some
internal values directly into it. For example, L3VPN needs to
map VPN route discriminators to private_id.
OTOH, u32 is enough for global_id, as these identifiers are dense.
Add a new protocol offering route aggregation.
User can specify list of route attributes in the configuration file and
run route aggregation on the export side of the pipe protocol. Routes are
sorted and for every group of equivalent routes new route is created and
exported to the routing table. It is also possible to specify filter
which will run for every route before aggregation.
Furthermore, it will be possible to set attributes of new routes
according to attributes of the aggregated routes.
This is a work in progress.
Original work by Igor Putovny, subsequent cleanups and finalization by
Maria Matejka.
For now, there are 4 phases: Necessary (device), Connector (kernel, pipe), Generator (static, rpki) and Regular.
Started and reconfigured are from Necessary to Regular, shutdown backwards.
This way, kernel can flush routes before actually being shutdown.
The problem happened like this:
1. Single route for the given net in table
2. A feed is started
3. The route is deleted (from another thread)
4. The feed finds an empty net, exports nothing, ignores journal (here is bug)
5. The route is added
6. The export transitions from FEEDING to READY
7. While processing the journal, the route deletion and addition combines into noop.
This way routes mysteriously disappeared in specific cases of link instability.
Problem fixed by explicitly marking the empty-net journal entries as processed in step 4.
This is a backport cherry-pick of commits
165156beebcce974e8ea
from the v3.0 branch as we need symbol hashes directly inside their
scopes for more general usage than before.
Due to a race condition between rta_apply_hostentry() and rt_update_hostentry(),
happening when a new route is inserted to a table, this commit makes it mandatory
to lock the next hop resolution table while resolving the next hop.
This may be slow, we'll fix it better in some future release
Most syntactic constructs in BIRD configuration (e.g. protocol options)
are defined as keywords, which are distinct from symbols (user-defined
names for protocols, variables, ...). That may cause backwards
compatibility issue when a new feature is added, as it may collide with
existing user names.
We can allow keywords to be shadowed by symbols in almost all cases to
avoid this issue.
This replaces the previous mechanism, where shadowable symbols have to be
explictly added to kw_syms.
Nonterminal bytestring allows to provide expressions to be evaluated in
places where BYTETEXT is used now: passwords, radv custom option.
Based on the patch from Alexander Zubkov <green@qrator.net>, thanks!
