Fix several errors including:
- Unaligned memory access to 'Length of Error Text' field
- No validation of 'Length of Encapsulated PDU' field
- No validation of 'Error Code' field
- No validation of characters in diagnostic message
We shouldn't convert bytes 2 and 3 of the PDU blindly, there are several
cases where these are used by bytes. Instead, the conversion is done
only where needed.
This fixes misinterpretation bug of ASPA PDU flags on little endian
architectures.
The END_OF_DATA PDU was extended in version 1, so it has different length
in different versions. We should do the PDU length check according to its
version.
RPKI-To-Router (RTR) sessions seem to be similar security-sensitivity as
IBGP sessions. BIRD already offered a choice of either "plain TCP" (meh)
or "SSH" (secure, albeit a bit more hassle to set up than TCP-MD5).
The patch adds TCP-MD5 as another option. TCP-MD5 for RTR is specified
through RFC 6810 section 7.3 and RFC 8210 section 9.3.
Minor changes by committer.
Allow to explicitly configure the source IP address for RPKI-To-Router
sessions. Predictable source addresses are useful for minimizing the
holes to be poked in ACLs.
Changed from 'source address' to 'local address' by committer.
With very busy deployments, RPKI may kill cache connection too early.
Instead of that, we want it to keep loading if any data is waiting to
be read and the reason for delay is just our congestion.
Also, when we kill the session because of actually slow cache, we want
to reload from scratch as the data we have is unreliable and nobody
knows whether the state is still valid.
There were some confusion about validity and usage of pflags, which
caused incorrect usage after some flags from (now removed) protocol-
specific area were moved to pflags.
We state that pflags:
- Are secondary data used by protocol-specific hooks
- Can be changed on an existing route (in contrast to copy-on-write
for primary data)
- Are irrelevant for propagation (not propagated when changed)
- Are specific to a routing table (not propagated by pipe)
The patch did these fixes:
- Do not compare pflags in rte_same(), as they may keep cached values
like BGP_REF_STALE, causing spurious propagation.
- Initialize pflags to zero in rte_get_temp(), avoid initialization in
protocol code, fixing at least two forgotten initializations (krt
and one case in babel).
- Improve documentation about pflags
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.
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).
Thanks to Alarig Le Lay for the suggestion.
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.
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.
The old timer interface is still kept, but implemented by new timers. The
plan is to switch from the old inteface to the new interface, then clean
it up.
