Ondrej Zajicek [Wed, 23 Aug 2023 13:55:31 +0000 (15:55 +0200)]
Nest: Treat VRF interfaces as inside respective VRFs
Despite not having defined 'master interface', VRF interfaces should be
treated as being inside respective VRFs. They behave as a loopback for
respective VRFs. Treating the VRF interface as inside the VRF allows
e.g. OSPF to pick up IP addresses defined on the VRF interface.
For this, we also need to tell apart VRF interfaces and regular interfaces.
Extend Netlink code to parse interface type and mark VRF interfaces with
IF_VRF flag.
Ondrej Zajicek [Mon, 21 Aug 2023 23:24:21 +0000 (01:24 +0200)]
BMP: Improve peer_down handling
Move all bmp_peer_down() calls to one place and make it synchronous with
BGP session down, ensuring that BMP receives peer_down before route
withdraws from flushing.
Also refactor bmp_peer_down_() message generating code.
Ondrej Zajicek [Fri, 18 Aug 2023 01:53:58 +0000 (03:53 +0200)]
BMP: Refactor route monitoring
- Manage BMP state through bmp_peer, bmp_stream, bmp_table structures
- Use channels and rt_notify() hook for route announcements
- Add support for post-policy monitoring
- Send End-of-RIB even when there is no routes
- Remove rte_update_in_notify() hook from import tables
- Update import tables to support channels
- Add bmp_hack (no feed / no flush) flag to channels
Alexander Zubkov [Fri, 23 Jun 2023 15:21:05 +0000 (17:21 +0200)]
RAdv: Add custom options
Currently one can use only a predefined set of advertised options in RAdv
protocol, which are supported by BIRD configuration. It would be convenient
to be able to specify other possible options at least manually as a blob
so one should not wait until it is supported in the code, released, etc.
This idea is inspired by presentation by Ondřej Caletka at CSNOG, in which
he noticed the lack of either PREF64 option or possibility to add custom
options in various software.
The patch makes it possible to define such options with the syntax:
Ondrej Zajicek [Thu, 18 May 2023 23:02:57 +0000 (01:02 +0200)]
BGP: Fix role check when no capability option is present
When an OPEN message without capability options was parsed, the remote
role field was not initialized with the proper (non-zero) default value,
so it was interpreted as if 'provider' was announced.
Ondrej Zajicek [Thu, 8 Jun 2023 02:56:41 +0000 (04:56 +0200)]
BMP: Support multiple instances of BMP protocol
Add internal BMP functions with plicit bmp_proto *p as first argument,
which allows using TRACE() macro. Keep list of BMP instances and call
internal functions. Old BMP functions are wrappers that call internal
functions for all enabled BMP instances.
Extract End-of-RIB mark into separate function.
Based on patch from Michal Zagorski <mzagorsk@akamai.com>. Thanks!
This adds support to the Babel protocol for the RTT extension specified
in draft-ietf-babel-rtt-extension. While this extension is not yet at the
RFC stage, it is one of the more useful extensions to Babel[0], so it
seems worth having in Bird as well.
The extension adds timestamps to Hello and IHU TLVs and uses these to
compute an RTT to each neighbour. An extra per-neighbour cost is then
computed from the RTT based on a minimum and maximum interval and cost
value specified in the configuration. The primary use case for this is
improving routing in a geographically distributed tunnel-based overlay
network.
The implementation follows the babeld implementation when picking
constants and default configuration values. It also uses the same RTT
smoothing algorithm as babeld, and follows it in adding a new 'tunnel'
interface type which enables RTT by default.
IO: Add current_time_now() function for immediate timestamp
Add a current_time_now() function which gets an immediate monotonic
timestamp instead of using the cached value from the event loop. This is
useful for callers that need precise times, such as the Babel RTT
measurement code.
Ondrej Zajicek [Thu, 18 May 2023 23:02:57 +0000 (01:02 +0200)]
BGP: Fix role check when no capability option is present
When an OPEN message without capability options was parsed, the remote
role field was not initialized with the proper (non-zero) default value,
so it was interpreted as if 'provider' was announced.
Ondrej Zajicek [Thu, 18 May 2023 13:55:45 +0000 (15:55 +0200)]
Lib: Improve IP/net hashing
Backport some changes from branch oz-parametric-hashes. Replace naive
hash function for IPv6 addresses, fix hashing of VPNx (where upper half
of RD was ignored), fix hashing of MPLS labels (where identity was used).
Ondrej Zajicek [Tue, 16 May 2023 11:25:48 +0000 (13:25 +0200)]
Nest: Add tests and benchmark for FIB
Basic fib_get() / fib_find() test for random prefixes, FIB_WALK() test,
and benchmark for fib_find(). Also generalize and reuse some code from
trie tests.
Ondrej Zajicek [Mon, 1 May 2023 01:35:21 +0000 (03:35 +0200)]
BMP: Use OPEN messages stored in BGP
The BMP protocol needs OPEN messages of established BGP sessions to
construct appropriate Peer Up messages. Instead of saving them internally
we use OPEN messages stored in BGP instances. This allows BMP instances
to be restarted or enabled later.
Because of this change, we can simplify BMP data structures. No need to
keep track of BGP sessions when we are not started. We have to iterate
over all (established) BGP sessions when the BMP session is established.
This is just a scaffolding now, but some kind of iteration would be
necessary anyway.
Also, the commit cleans up handling of msg/msg_length arguments to be
body/body_length consistently in both rx/tx and peer_up/peer_down calls.
Ondrej Zajicek [Thu, 27 Apr 2023 16:20:49 +0000 (18:20 +0200)]
Conf: Improve handling of keywords
For whatever reason, parser allocated a symbol for every parsed keyword
in each scope. That wasted time and memory. The effect is worsened with
recent changes allowing local scopes, so keywords often promote soft
scopes (with no symbols) to real scopes.
Do not allocate a symbol for a keyword. Take care of keywords that could
be promoted to symbols (kw_sym) and do it explicitly.
Maria Matejka [Thu, 20 Apr 2023 17:33:00 +0000 (19:33 +0200)]
Linpool: Fix lp_restore()
When lp_save() is called on an empty linpool, then some allocation is
done, then lp_restore() is called, the linpool is restored but the used
chunks are inaccessible. Fix it.
Ondrej Zajicek [Thu, 20 Apr 2023 15:14:45 +0000 (17:14 +0200)]
BMP: Silence some log messages
Hooks called from BGP to BMP should not log warning when BMP is not
connected, that is not an error (and we do not want to flood logs with
a ton of messages).
Blocked sk_send() should not log warning, that is expected situation.
Error during sk_send() is handled in error hook anyway.
Ondrej Zajicek [Thu, 20 Apr 2023 14:13:58 +0000 (16:13 +0200)]
BMP: Fix connection management
Replace broken TCP connection management with a simple state machine.
Handle failed attempts properly with a timeout, detect and handle TCP
connection close and try to reconnect after that. Remove useless
'station_connected' flag.
Keep open messages saved even after the BMP session establishment,
so they can be used after BMP session flaps.
Use local variable to refence relevant instance instead of using global
instance ptr. Also, use 'p' variable instead of 'bmp' so we can use
common macros like TRACE().
Most error handling code was was for cases that cannot happen,
or they would be code bugs (and should use ASSERT()). Keep error
handling for just for I/O errors, like in rest of BIRD.
Pawel Maslanka [Mon, 29 Mar 2021 20:45:21 +0000 (22:45 +0200)]
BMP protocol support
Initial implementation of a basic subset of the BMP (BGP Monitoring
Protocol, RFC 7854) from Akamai team. Submitted for further review
and improvement.
Maria Matejka [Thu, 16 Mar 2023 18:23:19 +0000 (19:23 +0100)]
BGP: Free bind applies also to outbound connections
Even though the free bind option is primarily meant to alleviate problems
with addresses assigned too late, it's also possible to use BIRD with AnyIP
configuration, assigning whole ranges to the machine. Therefore free bind
allows also to create an outbound connection from specific address even though
such address is not assigned.
Petr Vaněk [Mon, 6 Mar 2023 10:19:30 +0000 (11:19 +0100)]
Printf test suite fails on systems with musl libc because tests for "%m"
and "%M" formats expect "Input/output error" message but musl returns
"I/O error". Proposed change compares the printf output with string
returned from strerror function for EIO constant.
Maria Matejka [Wed, 22 Feb 2023 13:45:20 +0000 (14:45 +0100)]
Linpool flush drops all the allocated pages but one
When a linpool is used to allocate a one-off big load of memory, it
makes no sense to keep that amount of memory for future use inside the
linpool. Contrary to previous implementations where the memory was
directly free()d, we now use the page allocator which has an internal
cache which keeps the released pages for us and subsequent allocations
simply get these released pages back.
And even if the page cleanup routine kicks in inbetween, the pages get
only madvise()d, not munmap()ed so performance aspects are negligible.
This may fix some memory usage peaks in extreme cases.
Ondrej Zajicek [Sun, 19 Feb 2023 02:59:10 +0000 (03:59 +0100)]
Conf: Fix too early free of old configuration
The change 371eb49043d225d2bab8149187b813a14b4b86d2 introduced early free
of old_config. Unfortunately, it did not properly check whether it is not
still in use (blocked by obstacle during reconfiguration). Fix that.
It also means that we still could have a short peak when three configs
are in use (when a new reconfig is requeste while the previous one is
still active).
Babel: Keep separate auth PC counters for unicast and multicast
The babel protocol normally sends all its messages as multicast packets,
but the protocol specification allows most messages to be sent as either
unicast or multicast, and the two can be mixed freely. In particular, the
babeld implementation can be configured to unicast updates to all peers
instead of sending them as unicast.
Daniel discovered that this can cause problems with the packet counter
checks in the MAC extension due to packet reordering. This happens on WiFi
networks where clients have power save enabled (which is quite common in
infrastructure networks): in this case, the access point will buffer all
multicast traffic and only send it out along with its beacons, leading to a
maximum buffering in default Linux-based access point configuration of up
to 200 ms.
This means that a Babel sender that mixes unicast and multicast messages
can have the unicast messages overtake the multicast messages because of
this buffering; when authentication is enabled, this causes the receiver to
discard the multicast message when it does arrive because it now has a
packet counter value less than the unicast message that arrived before it.
Daniel observed that this happens frequently enough that Babel ceases to
work entirely when runner over a WiFi network.
The issue has been described in draft-ietf-babel-mac-relaxed, which is
currently pending RFC publication. That also describes two mitigation
mechanisms: Keeping separate PC counters for unicast and multicast, and
using a reorder window for PC values. This patch implements the former as
that is the simplest, and resolves the particular issue seen on WiFi.
Andreas Rammhold [Tue, 14 Feb 2023 15:17:03 +0000 (16:17 +0100)]
Babel: Implement IPv4 via IPv6 extension (RFC 9229)
The patch implements an IPv4 via IPv6 extension (RFC 9229) to the Babel
routing protocol (RFC 8966) that allows annoncing routes to an IPv4
prefix with an IPv6 next hop, which makes it possible for IPv4 traffic
to flow through interfaces that have not been assigned an IPv4 address.
The implementation is compatible with the current Babeld version.
Thanks to Toke Høiland-Jørgensen for early review on this work.
Ondrej Zajicek [Wed, 1 Feb 2023 15:15:13 +0000 (16:15 +0100)]
Nest: Minor cleanup in buildsystem
There ware missing dependencies for proto-build.c generation, which
sometimes lead to failed builds, and ignores changes in the set of
built protocols. Fix that, and also improve formatting of proto-build.c
Babel: Initialise source seqno from incoming message
When creating a new babel_source object we initialise the seqno to 0. The
caller will update the source object with the right metric and seqno value,
for both newly created and old source objects. However if we initialise the
source object seqno to 0 that may actually turn out to be a valid (higher)
seqno than the one in the routing table, because of seqno wrapping. In this
case the source metric will not be set properly, which breaks feasibility
tracking for subsequent updates.
To fix this, add a new initial_seqno argument to babel_get_source() which
is used when allocating a new object, and set that to the seqno value of
the update we're sending.
Juliusz noticed there were a couple of places we were doing straight
inequality comparisons of seqnos in Babel. This is wrong because seqnos can
wrap: so we need to use the modulo-64k comparison function for these cases
as well.
Introduce a strict-inequality version of the modulo-comparison for this
purpose.
Ondrej Zajicek [Sun, 22 Jan 2023 22:42:08 +0000 (23:42 +0100)]
BFD: Improve incoming packet matching
For active sessions, ignore received packets with zero local id and
mismatched remote id. That forces a session timeout instead of an
immediate session restart. It makes BFD sessions more resilient to
packet spoofing.
Ondrej Zajicek [Sun, 22 Jan 2023 17:12:04 +0000 (18:12 +0100)]
VRF: Fix issues with reconfiguration
Protocols receive if_notify() announcements that are filtered according
to their VRF setting, but during reconfiguration, they access iface_list
directly and forgot to check VRF setting here, which leads to all
interfaces be addedd.
Fix this issue for Babel, OSPF, RAdv and RIP protocols.
Maria Matejka [Wed, 18 Jan 2023 08:39:45 +0000 (09:39 +0100)]
Fix memory pre-allocation
When BIRD has no free memory mapped, it allocates several pages in
advance just to be sure that there is some memory available if needed.
This hysteresis tactics works quite well to reduce memory ping-ping with
kernel.
Yet it had a subtle bug: this pre-allocation didn't take a memory
coldlist into account, therefore requesting new pages from kernel even
in cases when there were other pages available. This led to slow memory
bloating.
To demonstrate this behavior fast enough to be seen well, you may:
* temporarily set the values in sysdep/unix/alloc.c as follows to
exacerbate the issue:
#define KEEP_PAGES_MAIN_MAX 4096
#define KEEP_PAGES_MAIN_MIN 1000
#define CLEANUP_PAGES_BULK 4096
* create a config file with several millions of static routes
* periodically disable all static protocols and then reload config
* log memory consumption
This should give you a steady growth rate of about 16kB per cycle. If
you don't set the values this high, the issue happens much more slowly,
yet after 14 days of running, you are going to see an OOM kill.
After this fix, pre-allocation uses the memory coldlist to get some hot
pages and the same test as described here gets you a perfectly stable
constant memory consumption (after some initial wobbling).
Thanks to NIX-CZ for reporting and helping to investigate this issue.
Thanks to Santiago for finding the cause in the code.
Ondrej Zajicek [Tue, 17 Jan 2023 16:13:50 +0000 (17:13 +0100)]
Alloc: Disable transparent huge pages
The usage pattern implemented in allocator seems to be incompatible with
transparent huge pages, as memory released using madvise(MADV_DONTNEED)
with regular page size and alignment does not seem to trigger demotion
of huge pages back to regular pages, even when significant number of
pages is released. Even if demotion is triggered when system memory
is low, it still breaks memory accounting.