Maria Matejka [Fri, 10 Apr 2020 22:35:52 +0000 (00:35 +0200)]
Split route data structure to storage (ro) / manipulation (rw) structures.
This should help a lot with keeping the route machinery and allocations
clean. This commit also changes behaviour of rte_update() with cached
rta. Newly, calling rte_update() keeps the number of rta references.
Maria Matejka [Sat, 20 Mar 2021 20:14:54 +0000 (21:14 +0100)]
KRT: Using obligatory export table when non-trivial filters are applied.
When the kernel filter is anything more sophisticated than FILTER_ACCEPT
or FILTER_REJECT, we should ensure that the old route being sent to the
kernel protocol is really what was sent there before. This fixes the old
misbehavior when an unfiltered old route was used.
BGP statistics code was preliminary and i wanted to replace it by
separate 'show X stats' command. The patch hides the preliminary
output in 'show protocols all' so it is not part of the released
version.
OSPFv3: Update neighbor authentication state from Hello packets
In OSPFv3, only Hello and DBDes packets contain flags specifying whether
RFC 7166 authentication trailer is used. Other packets are processed
based on stored authentication state in neighbor structure. Update this
state with each received Hello to handle authentication change from
reconfigurations.
Thanks to Joakim Tjernlund and Kenth Eriksson for the bugreport.
In general, events are code handling some some condition, which is
scheduled when such condition happened and executed independently from
I/O loop. Work-events are a subgroup of events that are scheduled
repeatedly until some (often significant) work is done (e.g. feeding
routes to protocol). All scheduled events are executed during each
I/O loop iteration.
Separate work-events from regular events to a separate queue and
rate limit their execution to a fixed number per I/O loop iteration.
That should prevent excess latency when many work-events are
scheduled at one time (e.g. simultaneous reload of many BGP sessions).
Vincent Bernat [Wed, 10 Feb 2021 15:53:57 +0000 (16:53 +0100)]
BGP: Add support for BGP hostname capability
This is an implementation of draft-walton-bgp-hostname-capability-02.
It is implemented since quite some time for FRR and in datacenter, this
gives a nice output to avoid using IP addresses.
It is disabled by default. The hostname is retrieved from uname(2) and
can be overriden with "hostname" option. The domain name is never set
nor displayed.
Nest: Automatic channel reloads based on RPKI changes
If there are roa_check() calls in channel filters, then the channel
subscribes to ROA table notifications, which are sent when ROA tables
are updated (subject to settle time) and trigger channel reload or
refeed.
Flag signalling that MP-BGP mode should be used got reset after first
batch of routes, so remaining routes were processed without that, leading
to missing MP_REACH_NLRI attribute.
With net.ipv4.conf.XXX.ignore_routes_with_linkdown sysctl, a user can
ensure the kernel does not use a route whose target interface is down.
Such route is marked with a 'dead' / RTNH_F_DEAD flag.
Ignore these routes or multipath nexthops during scan.
Add fake MP_REACH_NLRI attribute with BGP next hop when encoding MRT
table dumps for IPv6 routes. That is necessary to encode next hop as
NEXT_HOP attribute is not used for MP-BGP.
Direct BFD sessions needs to be dispatched not only by IP addresses, but
also by interfaces, in order to avoid collisions between neighbors with
the same IPv6 link-local addresses.
Extend BFD session hash_ip key by interface index to handle that. Use 0
for multihop sessions.
RPKI: Remove port (and SSH username) from 'Cache server' output line
It was mixed-up if hostname is IPv6 address, and reporting separate
values (like port) on separate lines fits better into key-value style
of 'show protocols all' output. Also, the patch simplifies transport
identification formatting (although it is unused now).
The patch add support for per-channel debug flags, currently just
'states', 'routes', and 'filters'. Flag 'states' is used for channel
state changes, remaining two for routes passed through the channel.
The per-protocol debug flags 'routes'/'filters' still enable reporting
of routes for all channels, to keep existing behavior.
The patch causes minor changes in some log messages.
Add 'weight' route attribute that allows to get and set ECMP weight of
nexthops. Similar to 'gw' attribute, it is limited to the first nexthop,
but it is useful for handling BGP multipath, where an ECMP route is
merged from multiple regular routes.
The log subsystem should be locked earlier, as default_log_list() may
internally manipulate with the current_log_list (if it is also a default
log list).
The static logging structures are reused, we need to reinitialize them
otherwise add_tail() would fail in debug build. Reinitializing these
structures should be fine as the list they belong to is being
reinitialized on entry to the very same function.
Thanks to Andreas Rammhold and Mikael Magnusson for patches.
lib/slab: introduce sl_allocz() function and use it in Babel
The babel protocol code was initialising objects returned from the slab
allocator by assigning to each of the struct members individually, but
wasn't touching the NODE member while doing so. This leads to warnings on
debug builds since commit:
To fix this, introduce an sl_allocz() variant of the slab allocator which
will zero out the memory before returning it, and switch all the babel call
sites to use this version. The overhead for doing this should be negligible
for small objects, and in the case of babel, the largest object being
allocated was being zeroed anyway, so we can drop the memset in
babel_read_tlv().
Static: Support for multiple routes with the same network
Add support for proper handling of multiple routes with the same network
to the static protocol. Routes are distinguished by internal index, which
is assigned automatically (sequentially for routes within each network).
Having different route preference or igp_metric attribute is optional.
OSPFv3: Fix intra-area-prefix-LSA origination on DR
When a new link-LSA is originated, we need to notify intra-area-prefix-LSA
handling, like when a new link-LSA is received. Otherwise a new network
prefix added to a DR is not propagated immediately.
BFD: Better handling of BFD options in BGP configs
Merge multiple BFD option blocks in BGP configs instead of using the last
one. That is necessary for proper handling of templates when BFD options
are used both in a BGP template and in a BGP protocol derived from that
template.
BFD session options are configured per interface in BFD protocol. This
patch allows to specify them also per-request in protocols requesting
sessions (currently limited to BGP).
Add 'ignore max length' option to RPKI protocol, which ignores received
max length in ROA records and instead uses max value (32 or 128). This
may be useful for implementing loose RPKI check for blackholes.
Sometimes multicast OSPF packet is received when neighbor adjacency is
not established. Such packet should be ignored earlier in packet
processing as otherwise it causes strange error messages when OSPFv3
authentication is enabled.
Put new non-best routes to the end of list instead of the second
position. Put updated routes to their old position. Position is changed
just by best route selection.
Show info from multiple protocols when protocol is not specified
Most commands like 'show ospf neighbors' fail when protocol is not
specified and there are multiple instances of given protocol type.
This is annoying in BIRD 2, as many protocols have IPv4 and IPv6
instances. The patch changes that by showing output from all protocol
instances of appropriate type.
Note that the patch also removes terminating cli_msg() call from these
commands and moves it to the common iterating code.
Kazuki Yamaguchi [Sun, 28 Jun 2020 13:37:01 +0000 (15:37 +0200)]
Filter: Improve handling of sets in BGP path masks
Compare the content of PM_ASN_SET in path masks. A reconfiguration
was not properly triggering a reload of affected protocols when the
members of a set in a path mask change.
Also, update the printing code to so that it can display sets in a path
mask.
Kazuki Yamaguchi [Sun, 28 Jun 2020 13:33:26 +0000 (15:33 +0200)]
Filter: Fix comparison of BGP path mask
Add a missing return statement. Path masks with the same length were all
considered the same. Comparing two with different length would cause
out-of-bounds memory access.
Add support for RTA_MULTIPATH attribute parsing for AF_MPLS routes.
BIRD is capable of installing a multipath route into kernel on Linux,
but it would not be seen because parsing fails. This made BIRD attempt
to install the same route repeatedly.
RPKI: Fix unnecessary reconnection on reconfiguration
Compare the new timing parameters with the old configuration, not with
the temporary state of the current connection.
The timing values in struct rpki_cache is updated by a version 1 End Of
Data PDU, unless this behavior is suppressed by the configuration
explicitly by the "keep" keyword. Consequently, every reconfiguration
of BIRD triggers a reconnection even if it is not necessary.
Log: Do not open logfiles when parse-and-exit option is active
This is a quick workaround for an issue where configured logfiles are
opened/created during parsing of a config file even when parse-and-exit
option is active. We should later refactor the logging code to avoid
opening log during parsing altogether.
Babel: Set onlink flag for IPv4 routes with unreachable next hop
If the next hop of a route is not a reachable address, the route should be
installed as onlink. This enables a configuration common in mesh networks
where the mesh interface is assigned a /32 and babel handles the routing by
installing onlink routes.
This issue has a long history. In 2012, we changed data field for
unnumbered PtP links from iface id (specified by RFC) to IP address based
on reports of bugs in Quagga that required it, and we used out-of-band
information to distinquish unnumberred PtPs with the same local IP
address.
Then with OSPF graceful restart implementation, we found that we can no
longer use out-of-band information, and we need to use only LSAdb info
for routing table calculation, but i forgot to finish handling of this
case, so multiple unnumbered PtPs with the same local IP addresses were
broken.
Considering that even recent Mikrotik RouterOS has broken next hop
calculation that depends on IP address in PtP link data field, we
cannot just switch back to the iface id for unnumbered PtP links.
The patch makes two changes: First, it goes back to use out-of-band
(position) info for distinguishing local interfaces in SPF when graceful
restart is not enabled, while still uses LSAdb-only approach for SPF
calculation when graceful restart is enabled.
Second, it adds OSPF interface option 'ptp address', which controls
whether IP address or iface id is used in data field. It is enabled
by default except for unnumbered PtP links with enabled graceful
restart.
Thanks to Kenth Eriksson for the bugreport and Joakim Tjernlund for
suggestions.
There is nothing in RFCs specifying that id 0 is not allowed. Some
implementations does not support it, while some other use key id 0 by
default. We allow it but start with key id 1 by default.
projects / thirdparty / bird.git / log
