Many protocols do almost the same when creating a rte_update request
before calling rte_update2(). This commit should simplify the protocol
side of the route-creation routine.
In BIRD, RX has lower priority than TX with the exception of RX from
control socket. The patch replaces heuristic based on socket type with
explicit mark and uses it for both control socket and BGP session waiting
to be established.
This should avoid an issue when during heavy load, outgoing connection
could connect (TX event), send open, but then failed to receive OPEN /
establish in time, not sending notifications between and therefore
got hold timer expired error from the neighbor immediately after it
finally established the connection.
When a kernel route changed, function krt_learn_scan() noticed that and
replaced the route in internal kernel FIB, but after that, function
krt_learn_prune() failed to propagate the new route to the nest, because
it confused the new route with the (removed) old best route and decided
that the best route did not changed.
Wow, the original code (and the bug) is almost 17 years old.
The patch adds support for channels, structures connecting protocols and
tables and handling most interactions between them. The documentation is
missing yet.
Explicit setting of AF_INET(6|) in IP socket creation. BFD set to listen
on v6, without setting the V6ONLY flag to catch both v4 and v6 traffic.
Squashing and minor changes by Ondrej Santiago Zajicek
Since 2.6.19, the netlink API defines RTA_TABLE routing attribute to
allow 32-bit routing table IDs. Using this attribute to index routing
tables at Linux, instead of 8-bit rtm_table field.
Symbol lookup by cf_find_symbol() not only did the lookup but also added
new void symbols allocated from cfg_mem linpool, which gets broken when
lookups are done outside of config parsing, which may lead to crashes
during reconfiguration.
The patch separates lookup-only cf_find_symbol() and config-modifying
cf_get_symbol(), while the later is called only during parsing. Also
new_config and cfg_mem global variables are NULLed outside of parsing.
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.
If the number of sockets is too much for select(), we should at least
handle it with proper error messages and reject new sockets instead of
breaking the event loop.
Thanks to Alexander V. Chernikov for the patch.
When a new route was imported from kernel and chosen as preferred, then
the old best route was propagated as a withdraw to the kernel protocol.
Under some circumstances such withdraw propagated to the BSD kernel could
remove the new alien route and thus reverting the import.
When an interface goes down, (Linux) kernel removes routes pointing to
that ifacem but does not send withdraws for them. We rescan the
kernel table to ensure synchronization.
Thanks to Alexander Demenshin for the bugreport.
Although RFC 3542 allows both cases, Theo de Raadt thinks
he knows better, and msg_controllen without last padding
fails on OpenBSD.
Thanks to Job Snijders for the bugreport.
I/O:
- BSD: specify src addr on IP sockets by IP_HDRINCL
- BSD: specify src addr on UDP sockets by IP_SENDSRCADDR
- Linux: specify src addr on IP/UDP sockets by IP_PKTINFO
- IPv6: specify src addr on IP/UDP sockets by IPV6_PKTINFO
- Alternative SKF_BIND flag for binding to IP address
- Allows IP/UDP sockets without tx_hook, on these
sockets a packet is discarded when TX queue is full
- Use consistently SOL_ for socket layer values.
OSPF:
- Packet src addr is always explicitly set
- Support for secondary addresses in BSD
- Dynamic RX/TX buffers
- Fixes some minor buffer overruns
- Interface option 'tx length'
- Names for vlink pseudoifaces (vlinkX)
- Vlinks use separate socket for TX
- Vlinks do not use fixed associated iface
- Fixes TTL for direct unicast packets
- Fixes DONTROUTE for OSPF sockets
- Use ifa->ifname instead of ifa->iface->name
RIP sockets for multiple ifaces collided, because we cannot bind to
a specific iface on BSD. Workarounded by SO_REUSEPORT.
Thanks to Eugene M. Zheganin for the bugreport.
The bug caused that krt_prefsrc attribute was not processed when a route
received from a kernel protocol was exported to another kernel protocol.
Thanks to Sergey Popovich for a bugreport.
Implemented eval command can be used to evaluate expressions.
The patch also documents echo command and allows to use log classes
instead of integer as a mask for echo.
Interfaces for OSPF and RIP could be configured to use (and request)
TTL 255 for traffic to direct neighbors.
Thanks to Simon Dickhoven for the original patch for RIPng.
Implements support for IPv6 traffic class, sets higher priority for OSPF
and RIP outgoing packets by default and allows to configure ToS/DS/TClass
IP header field and the local priority of outgoing packets.
Several new configure command variants:
configure undo - undo last reconfiguration
configure timeout - configure with scheduled undo if not confirmed in timeout
configure confirm - confirm last configuration
configure check - just parse and validate config file
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.
- ROA tables, which are used as a basic part for RPKI.
- Commands for examining and modifying ROA tables.
- Filter operators based on ROA tables consistent with RFC 6483.
Which was, actually, a bug in timers - on older kernel, monotonic timer
is missing and the other implementation started with now == 0, which
collides with usage 0 as a special value in timer->expires field.
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.
- Adds check to deny config file with no specified protocol to prevent
loading of empty config file.
- Moves CLI init before config parse to receive immediate error message
when cannot open control socket.
- Fixes socket name path check and other error handling in CLI init.
When device protocol goes down, interfaces should be flushed
asynchronously (in the same way like routes from protocols are flushed),
when protocol goes to DOWN/HUNGRY.
This fixes the problem with static routes staying in kernel routing
table after BIRD shutdown.
- 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).
There is no reak callback scheduler and previous behavior causes
bad things during hard congestion (like BGP hold timeouts).
Smart callback scheduler is still missing, but main loop was
changed such that it first processes all tx callbacks (which
are fast enough) (but max 4* per socket) + rx callbacks for CLI,
and in the second phase it processes one rx callback per
socket up to four sockets (as rx callback can be slow when
there are too many protocols, because route redistribution
is done synchronously inside rx callback). If there is event
callback ready, second phase is skipped in 90% of iterations
(to speed up CLI during congestion).
This also fixes bug that timer->recurrent was not cleared
in tm_new() and unexpected recurrence of startup timer
in BGP confused state machine and caused crash.
If other side of a socket is sending data faster than
BIRD is processing, BIRD does not schedule any other
callbacks (events, timers, rx/tx callbacks).
KRF_INSTALLED flag was not cleared during reconfiguration
that lead to not removing routes during reconfigure when
export rules changed.
We also should not try to remove routes we didi not installed,
on Linux this leads to warnings (as kernel checks route source
field and do not allow to remove non-bird routes) but we should
not rely on it.
Here is a patch fixing a bug that causes breakage of a local routing
table during shutdown of Bird. The problem was caused by shutdown
of 'device' protocol before shutdown of 'kernel' protocol. When
'device' protocol went down, the route (with local network prefix)
From different protocol (BGP or OSPF) became preferred and installed
to the kernel routing table. Such routes were broken (like
192.168.1.0/24 via 192.168.1.2). I think it is also the cause
of problem reported by Martin Kraus.
The patch disables updating of kernel routing table during shutdown of
Bird. I am not sure whether this is the best way to fix it, I would
prefer to forbid 'kernel' protocol to overwrite routes with
'proto kernel'.
The patch also fixes a problem that during shutdown sometimes routes
created by Bird remained in the kernel routing table.
Also, removed the `if (s)' test, because I believe that as the whole
socket interface doesn't accent NULL pointers, sk_reallocate() shouldn't
be the only exception.
