Most error messages in attribute processing are in rx/decode step and
these use L_REMOTE log class. But there are few that are in tx/export
step and these should use L_ERR log class.

Use tx-specific macro (REJECT()) in tx/export code and rename field
err_withdraw to err_reject in struct bgp_export_state to ensure that
appropriate error reporting macros are called in proper contexts.

Distinguish multiple causes of 'invalid next hop' message and report
the relevant next hop address.

Thanks to Simon Ruderich for the original patch.

Typical BGP error handling is treat-as-withdraw, where an invalid route
is replaced with a withdraw. Log route network when it happens.

Matous Holinka authored 3 years ago and Ondřej Zajíček committed 3 years ago

+ ubuntu:21.10 added into the pipeline,
- ubuntu:20.10 removed from the pipeline,

+ misc/docker/ubuntu-21.10-amd64/Dockerfile added,
- misc/docker/ubuntu-20.10-amd64/Dockerfile removed.

Add option 'netlink rx buffer' to specify netlink socket receive buffer
size. Uses SO_RCVBUFFORCE, so it can override rmem_max limit.

Thanks to Trisha Biswas and Michal for the original patches.

Unfortunately, SOL_NETLINK is both recently added and arch-dependent,
so we cannot just define it.

Add strict checking for netlink KRT dumps to avoid PMTU cache records
from FNHE table dump along with KRT.

Linux Kernel added FNHE table dump to the netlink API in patch:

https://patchwork.ozlabs.org/project/netdev/patch/8d3b68cd37fb5fddc470904cdd6793fcf480c6c1.1561131177.git.sbrivio@redhat.com/

Therefore, since Linux 5.3 these route cache entries are dumped together
with regular routes during periodic KRT scans, which in some cases may be
huge amount of useless data. This can be avoided by using strict checking
for netlink dumps:

https://lore.kernel.org/netdev/20181008031644.15989-1-dsahern@kernel.org/

The patch mitigates the risk of receiving unknown and potentially large
number of FNHE records that would block BIRD I/O in each sync. There is a
known issue caused by the GRE tunnels on Linux that seems to be creating
one FNHE record for each destination IP address that is routed through
the tunnel, even when the PMTU equals to GRE interface MTU.

Thanks to Tomas Hlavacek for the original patch.

Kernel uses cloned routes to keep route cache entries, but reports them
together with regular routes. They were skipped implicitly as they
do not have rtm_protocol filled. Add explicit check for cloned flag
and skip such routes explicitly.

Also, improve debug logs of skipped routes.

The BGP 'free bind' option applies the IP_FREEBIND/IPV6_FREEBIND
socket option for the BGP listening socket.

Thanks to Alexander Zubkov for the idea.

Alexander Zubkov authored 3 years ago and Ondřej Zajíček committed 3 years ago

Add option to socket interface for nonlocal binding, i.e. binding to an
IP address that is not present on interfaces. This behaviour is enabled
when SKF_FREEBIND socket flag is set. For Linux systems, it is
implemented by IP_FREEBIND socket flag.

Minor changes done by commiter.

Currently, BIRD ignores dead routes to consider them absent. But it also
ignores its own routes and thus it can not correctly manage such routes
in some cases. This patch makes an exception for routes with proto bird
when ignoring dead routes, so they can be properly updated or removed.

Thanks to Alexander Zubkov for the original patch.

Function nl_parse_multipath() should handle errors internally.

Lexer expression for bytestring was too loose, accepting also
full-length IPv6 addresses. It should be restricted such that
colon is used between every byte or never.

Fix the regex and also add some test cases for it.

Thanks to Alexander Zubkov for the bugreport

Matous authored 3 years ago and Ondřej Zajíček committed 3 years ago

'registry.labs.nic.cz' -> 'registry.nic.cz' changed

Alexander Zubkov authored 3 years ago and Ondřej Zajíček committed 3 years ago

Add operators .min and .max to find minumum or maximum element in sets
of types: clist, eclist, lclist. Example usage:

bgp_community.min
bgp_ext_community.max
filter(bgp_large_community, [(as1, as2, *)]).min

Signed-off-by: Alexander Zubkov <green@qrator.net>

Alexander Zubkov authored 3 years ago and Ondřej Zajíček committed 3 years ago

Add operators that can be used to pick components from
pair (standard community) or lc (large community) types.
For example:

(10, 20).asn --> 10
(10, 20).data --> 20

(10, 20, 30).asn --> 10
(10, 20, 30).data1 --> 20
(10, 20, 30).data2 --> 30

Signed-off-by: Alexander Zubkov <green@qrator.net>

The BSD kernel does not support the onlink flag and BIRD does not use
direct routes for next hop validation, instead depends on interface
address ranges. We would like to handle PtMP cases with only host
addresses configured, like:

  ifconfig wg0 192.168.0.10/32
  route add 192.168.0.4 -iface wg0
  route add 192.168.0.8 -iface wg0

To accept BIRD routes with onlink next-hop, like:

  route 192.168.42.0/24 via 192.168.0.4%wg0 onlink

BIRD would dismiss the route when receiving from the kernel, as the
next-hop 192.168.0.4 is not part of any interface subnet and onlink
flag is not kept by the BSD kernel.

The commit fixes this by assuming that for routes received from the
kernel, any next-hop is onlink on ifaces with only host addresses.

Thanks to Stefan Haller for the original patch.

Job Snijders authored 3 years ago and Ondřej Zajíček committed 3 years ago

RFC 6810 and RFC 8210 specify that the "Max Length" value MUST NOT be
less than the Prefix Length element (underflow). On the other side,
overflow of the Max Length element also is possible, it being an 8-bit
unsigned integer allows for values larger than 32 or 128. This also
implicitly ensures there is no overflow of "Length" value.

When a PDU is received where the Max Length field is corrputed, the RTR
client (BIRD) should immediately terminate the session, flush all data
learned from that cache, and log an error for the operator.

Minor changes done by commiter.

Simon Ruderich authored 3 years ago and Ondřej Zajíček committed 3 years ago

The option was removed in d15b0b0a ("BGP redesign", 2016-12-07)
but the documentation wasn't updated.

Compare all IA_* flags that are set by sysdep iface code.

The old code ignores IA_SECONDARY flag when comparing whether iface
address updates from kernel changed anything. This is usually not an
issue as kernel removes all secondary addresses due to removal of the
primary one, but it breaks when sysctl 'promote_secondaries' is enabled
and kernel promotes secondary addresses to primary ones.

Thanks to 'Alexander' for the bugreport.

This feature is intended mostly for checking that BIRD's allocation
strategies don't consume much memory space. There are some cases where
withdrawing routes in a specific order lead to memory fragmentation and
this output should give the user at least a notion of how much memory is
actually used for data storage and how much memory is "just allocated"
or used for overhead.

Also raising the "system allocator overhead estimation" from 8 to 16
bytes; it is probably even more. I've found 16 as a local minimum in
best scenarios among reachable machines. I couldn't find any reasonable
method to estimate this value when BIRD starts up.

This commit also fixes the inaccurate computation of memory overhead for
slabs where the "system allocater overhead estimation" was improperly
added to the size of mmap-ed memory.

BIRD implements shutdown by reconfiguring to fake empty configuration.
Such fake config structure is created from the last running config and
shares some data, including symbol table. This allows access to (removed)
routing tables and causes crash when 'show route' command is used during
shutdown.

Clean up symbol table, table list and links to default tables, so removed
routing tables cannot be accessed during shutdown.

Remove assumption that main channel is the only channel.

Pipes copy the original rte with old values, so they require rte to be
exported with stored tmpattrs. Other protocols access stored attributes
using eattr list, so they require rte to be exported with expanded
tmpattrs. This is temporary hack, we plan to remove whoe tmpattr mechanism.

Thanks to Paul Donohue for the bugreport.

This reverts commit f8e273b5.

In most cases of export there is no need to store back temporary
attributes to rte, as receivers (protocols) access eattr list anyway.
But pipe copies the original rte with old values, so we should store
tmpattrs also during export.

Thanks to Paul Donohue for the bugreport.

Just use hello_expiry for that, keep init_expiry for initial
unauthentized neighbors.

One of previous patches broke password list parsing code, fix that.

Some cleanups and bugfixes to the previous patch, including:

 - Fix rate limiting in index mismatch check

 - Fix missing BABEL_AUTH_INDEX_LEN in auth_tx_overhead computation

 - Fix missing auth_tx_overhead recalculation during reconfiguration

 - Fix pseudoheader construction in babel_auth_sign() (sport vs fport)

 - Fix typecasts for ptrdiffs in log messages

 - Make auth log messages similar to corresponding RIP/OSPF ones

 - Change auth log messages for events that happen during regular
   operation to debug messages

 - Switch meaning of babel_auth_check*() functions for consistency
   with corresponding RIP/OSPF ones

 - Remove requirement for min/max key length, only those required by
   given MAC code are enforced

Toke Høiland-Jørgensen authored 4 years ago and Ondřej Zajíček committed 3 years ago

This implements support for MAC authentication in the Babel protocol, as
specified by RFC 8967. The implementation seeks to follow the RFC as close
as possible, with the only deliberate deviation being the addition of
support for all the HMAC algorithms already supported by Bird, as well as
the Blake2b variant of the Blake algorithm.

For description of applicability, assumptions and security properties,
see RFC 8967 sections 1.1 and 1.2.

Toke Høiland-Jørgensen authored 4 years ago and Ondřej Zajíček committed 3 years ago

In preparation for adding authentication checks, refactor the TLV
walking code so it can be reused for a separate pass of the packet
for authentication checks.

Toke Høiland-Jørgensen authored 4 years ago and Ondřej Zajíček committed 3 years ago

Add min/max key length fields to the MAC algorithm description and
validate configured keys before they are used.