In some circumstances during reconfiguration, routes propagated by pipes
to other tables may hang there even after the primary routes are removed.
There is already a workaround for this issue in the code which removes
these stale routes by flush process when source protocols are shut down.
This patch is a cleaner fix and allows to simplify the flush process
When route was propagated to another rtable through a pipe and then the
pipe was reconfigured softly in such a way that any subsequent route
updates are filtered, then the source protocol shutdown didn't clean up
the route in the second rtable which caused stale routes and potential
crashes.
Temporary dummy routes created by a kernel protocol during routing table
scan get mixed with real routes propagated from another kernel protocol
through a pipe.
The RAdv protocol could be configured to change its behavior based on
availability of routes, e.g., do not announce router lifetime when a
default route is not available.
When 'import keep rejected' protocol option is activated, routes
rejected by the import filter are kept in the routing table, but they
are hidden and not propagated to other protocols. It is possible to
examine them using 'show route rejected'.
Allows to send and receive multiple routes for one network by one BGP
session. Also contains necessary core changes to support this (routing
tables accepting several routes for one network from one protocol).
It needs some more cleanup before merging to the master branch.
When a protocol went down, all its routes were flushed in one step, that
may block BIRD for too much time. The patch fixes that by limiting
maximum number of routes flushed in one step.
The nest-protocol interaction is changed to better handle multitable
protocols. Multitable protocols now declare that by 'multitable' field,
which tells nest that a protocol handles things related to proto-rtable
interaction (table locking, announce hook adding, reconfiguration of
filters) itself.
Filters and stats are moved to announce hooks, a protocol could have
different filters and stats to different tables.
The patch is based on one from Alexander V. Chernikov, thanks.
Hostcache is a structure for monitoring changes in a routing table that
is used for routes with dynamic/recursive next hops. This is needed for
proper iBGP next hop handling.
In usual configuration, such export is already restricted
with the aid of the direct protocol but there are some
races that can circumvent it. This makes it harder to
break kernel device routes. Also adds an option to
disable this restriction.
- BSD kernel syncer is now self-conscious and can learn alien routes
- important bugfix in BSD kernel syncer (crash after protocol restart)
- many minor changes and bugfixes in kernel syncers and neighbor cache
- direct protocol does not generate host and link local routes
- min_scope check is removed, all routes have SCOPE_UNIVERSE by default
- also fixes some remaining compiler warnings
It seems that by adding one pipe-specific exception to route
announcement code and by adding one argument to rt_notify() callback i
could completely eliminate the need for the phantom protocol instance
and therefore make the code more straightforward. It will also fix some
minor bugs (like ignoring debug flag changes from the command line).
When uncofiguring the pipe and the peer table, the peer table was
unlocked when pipe protocol state changed to down/flushing and not to
down/hungry. This leads to the removal of the peer table before
the routes from the pipe were flushed.
The fix leads to adding some pipe-specific hacks to the nest,
but this seems inevitable.
If protocol announces a route, route is accepted by import filter to
routing table, and later it announces replacement of that route that is
rejected by import filter, old route remains in routing table.
Routes comming through pipe from primary to secondary table were
filtered by both EXPORT and IMPORT filters, but they should be
only filtered by EXPORT filters.
contains all attributes, not just the temporary ones. This avoids having
to merge the lists inside protocols or doing searches on both of them.
Also, do filtering of routes properly. (I'd like to avoid it, but it's
needed at least in the krt protocol.)
show the routing table as exported to the protocol given resp. as returned
from its import control hook.
To get handling of filtered extended attributes right (even in the old
`show route where <filter>' command), the get_route_info hook gets an
attribute list and all protocol specific rte attributes are contained
there as temporary ones. Updated RIP to do that.
Added ea_append() which joins two ea_list's.
Please try compiling your code with --enable-warnings to see them. (The
unused parameter warnings are usually bogus, the unused variable ones
are very useful, but gcc is unable to control them separately.)
of calling the protocols manually.
Implemented printing of dynamic attributes in `show route all'.
Each protocol can now register its own attribute class (protocol->attr_class,
set to EAP_xxx) and also a callback for naming and formatting of attributes.
The callback can return one of the following results:
GA_UNKNOWN Attribute not recognized.
GA_NAME Attribute name recognized and put to the buffer,
generic code should format the value.
GA_FULL Both attribute name and value put to the buffer.
Please update protocols generating dynamic attributes to provide
the attr_class and formatting hook.
The changes are just too extensive for lazy me to list them
there, but see the comment at the top of sysdep/unix/krt.c.
The code got a bit more ifdeffy than I'd like, though.
Also fixed a bunch of FIXME's and added a couple of others. :)
definitely gone. Both rte_update() and rte_discard() have an additional
argument telling which table should they modify.
Also, rte_update() no longer walks the whole protocol list -- each table
has a list of all protocols connected to this table and having the
rt_notify hook set. Each protocol can also freely decide (by calling
proto_add_announce_hook) to connect to any other table, but it will
be probably used only by the table-to-table protocol.
The default debugging dumps now include all routing tables and also
all their connections.
o Introduced rte_cow() which should be used for copying on write the
rte's in filters. Each rte now carries a flag saying whether it's
a real route (possessing table linkage and other insignia) or a local
copy. This function can be expected to be fast since its fast-path
is inlined.
o Introduced rte_update_pool which is a linear memory pool used for
all temporary data during rte_update. You should not reference it directly
-- instead use a pool pointer passed to all related functions.
o Split rte_update to three functions:
rte_update The front end: handles all checking, inbound
filtering and calls rte_recalculate() for the
final version of the route.
rte_recalculate Update the table according to already filtered route.
rte_announce Announce routing table changes to all protocols,
passing them through export filters and so on.
The interface has _not_ changed -- still call rte_update() and it will
do the rest for you automagically.
o Use new filtering semantics to be explained in a separate mail.
o Now compatible with filtering.
o Learning of kernel routes supported only on CONFIG_SELF_CONSCIOUS
systems (on the others it's impossible to get it semantically correct).
o Learning now stores all of its routes in a separate fib and selects
the ones the kernel really uses for forwarding packets.
o Better treatment of CONFIG_AUTO_ROUTES ports.
o Lots of internal changes.
nodes having no routes attached. Such cleanup must be done from event handler
since most functions manipulating the routing tables expect network entries
won't disappear from under their hands and it's also probably faster when
done asynchronously.
o rte can now contain a pointer to both cached and uncached rta. Protocols
which don't need their own attribute caching can now just fill-in a rta,
link it to rte without any calls to attribute cache and call rte_update()
which will replace rte->attrs by a cached copy.
o In order to support this, one of previously pad bytes in struct rta
now holds new attribute flags (RTAF_CACHED). If you call rte_update()
with uncached rta, you _must_ clear these flags. In other cases rta_lookup()
sets it appropriately.
o Added rte_free() which is useful when you construct a rte and then the
circumstances change and you decide not to use it for an update. (Needed
for temporary rte's in kernel syncer...)
protocol callbacks for route insertion and deletion from the central table.
RIP should maintain its own per-protocol queue of existing routes, scan it
periodically and call rte_discard() for routes that have timed out.
