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
All the 'dump something' CLI commands now have a new mandatory
argument -- name of the file where to dump the data. This allows
for more flexible dumping even for production deployments where
the debug output is by default off.
Also the dump commands are now restricted (they weren't before)
to assure that only the appropriate users can run these time consuming
commands.
When printing near the end of the buffer, there was an overflow in two cases:
(1) %c and size is zero
(2) %1N, %1I, %1I4, %1I6 (auto-fill field_width for Net or IP), size is
more than actual length of the net/ip but less than the auto-filled
field width.
Manual code examination showed that nothing could have ever triggered
this behavior. All older versions of BIRD, including BIRD 3 development
versions, are totally safe. This exact overflow has been found while
implementing a new feature in later commits.
Instead of several levels of functions, just have two functions
(one for routes, the other for end-of-rib), this allows to create
messages in a simple linear fashion.
Also reduce three duplicite functions to construct BGP header for
BMP messages to just one.
This commit is quite a substantial rework of the underlying layers in
BMP TX:
- several unnecessary layers of indirection dropped, including most of
the original BMP's buffer machinery
- all messages are now written directly into one protocol's buffer
allocated for the whole time big enough to fit every possible message
- output blocks are allocated by pages and immediately returned when
used, improving the overall memory footprint
- no intermediary allocation is done from the heap altogether
- there is a documented and configurable limit on the TX queue size
Actually, completely rewritten the original patch as in v3, the logging
initialization is much more complex and requires allocation.
This way, to bootstrap properly, the logger has a pre-defined log target
to stderr.
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.
