Commit graph

3934 commits

Author SHA1 Message Date
Maria Matejka
71b3456eed Better profylaction recursive route loops
In some specific configurations, it was possible to send BIRD into an
infinite loop of recursive next hop resolution. This was caused by route
priority inversion.

To prevent priority inversions affecting other next hops, we simply
refuse to resolve any next hop if the best route for the matching prefix
is recursive or any other route with the same preference is recursive.

Next hop resolution doesn't change route priority, therefore it is
perfectly OK to resolve BGP next hops e.g. by an OSPF route, yet if the
same (or covering) prefix is also announced by iBGP, by retraction of
the OSPF route we would get a possible priority inversion.
2022-09-06 15:15:03 +02:00
Maria Matejka
d2c1036a42 Merge branch 'mq-fix-eattr-setting' into backport 2022-08-18 22:07:50 +02:00
Maria Matejka
dc28c6ed1c Simplified the protocol hookup code in Makefiles 2022-08-18 22:07:30 +02:00
Maria Matejka
16ac6c3c74 Fixed initialization of Linux kernel route attributes 2022-08-18 17:44:00 +02:00
Maria Matejka
bc4ad83dac Merge commit '082905a8' into HEAD 2022-08-03 15:04:42 +02:00
Maria Matejka
73abd91ac6 rip_rte_better() uses the IGP_METRIC_UNKNOWN instead of protocol-specific infinity 2022-08-03 15:04:28 +02:00
Ondrej Zajicek
082905a833 Merge branch 'master' into backport 2022-07-27 00:47:24 +02:00
Ondrej Zajicek
ddb1bdf281 Netlink: Restrict route replace for IPv6
Seems like the previous patch was too optimistic, as route replace is
still broken even in Linux 4.19 LTS (but fixed in Linux 5.10 LTS) for:

  ip route add 2001:db8::/32 via fe80::1 dev eth0
  ip route replace 2001:db8::/32 dev eth0

It ends with two routes instead of just the second.

The issue is limited to direct and special type (e.g. unreachable)
routes, the patch restricts route replace for cases when the new route
is a regular route (with a next hop address).
2022-07-26 18:45:20 +02:00
Ondrej Zajicek
722daa9500 Netlink: Simplify handling of IPv6 ECMP routes
When IPv6 ECMP support first appeared in Linux kernel, it used different
API than IPv4 ECMP. Individual next hops were updated and announced
separately, instead of using RTA_MULTIPATH as in IPv4. This has several
drawbacks and requires complex code to merge received notifications to
one multipath route.

When Linux came with IPv6 RTA_MULTIPATH support, the initial versions
were somewhat buggy, so we kept using the old API for updates (splitting
multipath routes to sequences of route updates), while accepting both
old-style routes and RTA_MULTIPATH routes in scans / notifications.

As IPv6 RTA_MULTIPATH support is here for a long time, this patch fully
switches Netlink to the IPv6 RTA_MULTIPATH API and removes old complex
code for handling individual next hop announces.

The required Linux version is at least 4.11 for reliable operation.

Thanks to Daniel Gröber for the original patch.
2022-07-25 00:11:40 +02:00
Ondrej Zajicek
2e484f8d29 Merge branch 'master' into backport 2022-07-24 20:08:02 +02:00
Ondrej Zajicek
534d0a4b44 KRT: Scan routing tables separetely on linux to avoid congestion
Remove compile-time sysdep option CONFIG_ALL_TABLES_AT_ONCE, replace it
with runtime ability to run either separate table scans or shared scan.

On Linux, use separate table scans by default when the netlink socket
option NETLINK_GET_STRICT_CHK is available, but retreat to shared scan
when it fails.

Running separate table scans has advantages where some routing tables are
managed independently, e.g. when multiple routing daemons are running on
the same machine, as kernel routing table modification performance is
significantly reduced when the table is modified while it is being
scanned.

Thanks Daniel Gröber for the original patch and Toke Høiland-Jørgensen
for suggestions.
2022-07-24 02:15:20 +02:00
Maria Matejka
432dfe3b9b Fixed a rarely used part of Babel: comparing two routes in table by their metric 2022-07-22 15:48:20 +02:00
Maria Matejka
4d48ede51d Revert "Export table: Delay freeing of old stored route."
This reverts commit cee0cd148c.
This change is not needed in version 2 and the surrounding code has
disappeared mostly in version 3.
2022-07-22 15:37:21 +02:00
Ondrej Zajicek
971721c9b5 BGP: Minor improvements to BGP roles
Add support for bgp_otc in filters and warning for configuration
inside confederations.
2022-07-12 15:03:17 +02:00
Eugene Bogomazov
c73b5d2d3d BGP: Implement BGP roles
Implement BGP roles as described in RFC 9234. It is  a mechanism for
route leak prevention and automatic route filtering based on common BGP
topology relationships. It defines role capability (controlled by 'local
role' option) and OTC route attribute, which is used for automatic route
filtering and leak detection.

Minor changes done by commiter.
2022-07-11 17:25:54 +02:00
Maria Matejka
b5c8fce284 Added forgotten route source locking in flowspec validation 2022-07-11 13:04:01 +02:00
Maria Matejka
2e5bfeb73a Merge remote-tracking branch 'origin/master' into backport 2022-07-11 11:08:10 +02:00
Maria Matejka
d429bc5c84 Merge commit 'beb5f78a' into backport 2022-07-11 10:41:17 +02:00
Maria Matejka
7e9cede1fd Merge version 2.0.10 into backport 2022-07-10 14:19:24 +02:00
Ondrej Zajicek (work)
cb339a3067 Filter: Implement for loops
For loops allow to iterate over elements in compound data like BGP paths
or community lists. The syntax is:

  for [ <type> ] <variable> in <expr> do <command-body>
2022-06-27 21:13:32 +02:00
Ondrej Zajicek (work)
1ac8e11bba Filter: Implement mixed declarations of local variables
Allow variable declarations mixed with code, also in nested blocks with
proper scoping, and with variable initializers. E.g:

function fn(int a)
{
  int b;
  int c = 10;

  if a > 20 then
  {
    b = 30;
    int d = c * 2;
    print a, b, c, d;
  }

  string s = "Hello";
}
2022-06-27 21:13:32 +02:00
Ondrej Zajicek (work)
a2527ee53d Filter: Improve handling of stack frames in filter bytecode
When f_line is done, we have to pop the stack frame. The old code just
removed nominal number of args/vars. Change it to use stored ventry value
modified by number of returned values. This allows to allocate variables
on a stack frame during execution of f_lines instead of just at start.

But we need to know the number of returned values for a f_line. It is 1
for term, 0 for cmd. Store that to f_line during linearization.
2022-06-27 21:13:32 +02:00
Ondrej Zajicek (work)
f31f4e6eef Filter: Simplify handling of command sequences
Command sequences in curly braces used a separate nonterminal in grammar.
Handle them as a regular command.
2022-06-27 21:13:31 +02:00
Ondrej Zajicek (work)
1e6acf34bb Filter: Fix bug in variable shadowing
When a new variable used the same name as an existing symbol in an outer
scope, then offset number was defined based on a scope of the existing
symbol ($3) instead of a scope of the new symbol (sym_). That can lead
to two variables sharing the same memory slot.
2022-06-27 21:13:31 +02:00
Ondrej Zajicek (work)
946cedfcfe Filter: Implement soft scopes
Soft scopes are anonymous scopes that most likely do not contain any
symbol, so allocating regular scope is postponed when it is really
needed.
2022-06-27 21:13:31 +02:00
Ondrej Zajicek (work)
26bc4f9904 Filter: Implement direct recursion
Direct recursion almost worked, just crashed on function signature check.
Split function parsing such that function signature is saved before
function body is processed. Recursive calls are marked so they can be
avoided during f_same() and similar code walking.

Also, include tower of hanoi solver as a test case.
2022-06-27 21:13:31 +02:00
Ondrej Zajicek (work)
fb1d8f6513 Filter: Apply constant promotion for FI_EQ / FI_NEQ
Equality comparison is defined on all values, even of different
types, but we still want to do constant promotion if possible.
2022-06-27 21:13:31 +02:00
Alexander Zubkov
b2d6d2948a Filter: Add literal for empty set
Add literal for empty set [], which works both for tree-based sets
and prefix sets by using existing constant promotion mechanism.

Minor changes by committer.
2022-06-27 21:13:31 +02:00
Ondrej Zajicek (work)
8f3c6151b4 Nest: Cleanups in as_path_filter()
Use struct f_val as a common argument for as_path_filter(), as suggested
by Alexander Zubkov. That allows to use NULL sets as valid arguments.
2022-06-27 21:13:31 +02:00
Ondrej Zajicek (work)
9b302c133f Filter: Ensure that all expressions declared return type
All instructions with a return value (i.e. expressions, ones with
non-zero outval, third argument in INST()) should declare their return
type. Check that automatically by M4 macros.

Set outval of FI_RETURN to 0. The instruction adds one value to stack,
but syntactically it is a statement, not an expression.

Add fake return type declaration to FI_CALL, otherwise the automatic
check would fail builds.
2022-06-27 21:13:31 +02:00
Ondrej Zajicek (work)
cde8094c1f Filter: Improve description of type system 2022-06-27 21:13:31 +02:00
Ondrej Zajicek (work)
93d6096c87 Filter: Implement type checks for function calls
Keep list of function parameters in f_line and use it to verify
types of arguments for function calls. Only static type checks
are implemented.
2022-06-27 21:13:31 +02:00
Ondrej Zajicek (work)
4c0c507b1f Filter: Clean up function call instruction
Pass instructions of function call arguments as vararg arguments to
FI_CALL instruction constructor and move necessary magic from parser
code to interpreter / instruction code.
2022-06-27 21:13:31 +02:00
Maria Matejka
beb5f78ada Preexport callback now takes the channel instead of protocol as argument
Passing protocol to preexport was in fact a historical relic from the
old times when channels weren't a thing. Refactoring that to match
current extensibility needs.
2022-06-27 19:04:24 +02:00
Ondrej Zajicek
b867c798c3 NEWS and version update 2022-06-16 02:58:37 +02:00
Maria Matejka
141fb51f1a IPv4 flowspec literals should reject IPv6 prefices in a well-behaved way
When writing flow4 { dst 2001:db8::dead:beef/128; }, BIRD crashed on an
not-well-debuggable segfault as it tried to copy the whole 128-bit
prefix into an IPv4-sized memory.
2022-06-07 10:38:32 +02:00
Ondrej Zajicek
ad686c55c3 Babel: Do not try to remove multicast seqno request objects from neighbour list
The Babel seqno request code keeps track of which seqno requests are
outstanding for a neighbour by putting them onto a per-neighbour list. When
reusing a seqno request, it will try to remove this node, but if the seqno
request in question was a multicast request with no neighbour attached this
will result in a crash because it tries to remove a list node that wasn't
added to any list.

Fix this by making the list remove conditional. Also fix neighbor removal
which were changing seqno requests to multicast ones instead of removing
them.

Fixes: ebd5751cde ("Babel: Seqno requests are properly decoupled from
neighbors when the underlying interface disappears").

Based on the patch from Toke Høiland-Jørgensen <toke@toke.dk>,
bug reported by Stefan Haller <stefan.haller@stha.de>, thanks.
2022-06-05 04:11:32 +02:00
Ondrej Zajicek
f39e9aa203 IO: Improve resolution of latency debugging messages 2022-06-04 17:54:08 +02:00
Ondrej Zajicek
a8a3d95be5 Nest: Improve GC strategy for rtables
Use timer (configurable as 'gc period') to schedule routing table
GC/pruning to ensure that prune is done on time but not too often.

Randomize GC timers to avoid concentration of GC events from different
tables in one loop cycle.

Fix a bug that caused minimum inter-GC interval be 5 us instead of 5 s.

Make default 'gc period' adaptive based on number of routing tables,
from 10 s for small setups to 600 s for large ones.

In marge multi-table RS setup, the patch improved time of flushing
a downed peer from 20-30 min to <2 min and removed 40s latencies.
2022-06-04 17:34:57 +02:00
Maria Matejka
652be92a21 Merge remote-tracking branch 'origin/master' into haugesund-to-2.0 2022-05-30 15:20:21 +02:00
Maria Matejka
f196b12c62 Merge commit '9eec503b251c3388579032b300d32640403d8612' into haugesund-to-2.0 2022-05-30 15:20:05 +02:00
Maria Matejka
097f157182 Merge commit '692055e3df6cc9f0d428d3b0dd8cdd8e825eb6f4' into haugesund-to-2.0 2022-05-30 15:17:52 +02:00
Ondrej Zajicek
9e60b500c7 CI: Remove broken FreeBSD builds
We currently do not have FreeBSD CI workers.
2022-05-27 16:07:50 +02:00
Ondrej Zajicek
a9c19b923c BGP: Display neighbor port on show protocol 2022-05-21 16:21:34 +02:00
Ondrej Zajicek
7bb06b34a1 RPKI: Display cache server port on show protocol
Thanks to Luiz Amaral for the idea.
2022-05-21 16:03:08 +02:00
Luiz Amaral
9a9439d5e1 RPKI: Implement VRF support 2022-05-19 19:43:59 +02:00
Ondrej Zajicek
ba2a076001 BGP: Improve tx performance during feed/flush
The prefix hash table in BGP used the same hash function as the rtable.
When a batch of routes are exported during feed/flush to the BGP, they
all have similar hash values, so they are all crowded in a few slots in
the BGP prefix table (which is much smaller - around the size of the
batch - and uses higher bits from hash values), making it much slower due
to excessive collisions. Use a different hash function to avoid this.

Also, increase the batch size to fill 4k BGP packets and increase minimum
BGP bucket and prefix hash sizes to avoid back and forth resizing during
flushes.

This leads to order of magnitude faster flushes (on my test data).
2022-05-15 15:05:37 +02:00
Alexander Zubkov
5299fb9db0 Fixed spurious undef of route attributes 2022-05-04 15:37:23 +02:00
Vincent Bernat
207ac48533 Doc: fix mating -> matching in flowspec section 2022-04-22 17:06:27 +02:00
Toke Høiland-Jørgensen
d829800138 Babel: Fix compilation when LOCAL_DEBUG is set in packets.c
The debug output was not updated with the rest of the code, so packets.c
fails to compile if LOCAL_DEBUG is set.
2022-04-22 17:04:56 +02:00