AppLayerRegisterParser was creating a link error when attempting
to use a convenience library for the Suricata C code, then linking
the library of C code with the library of Rust code into a final
Suricata executable, or use with fuzz targets.
By moving AppLayerRegisterParser to the context structure and
calling it like a callback the circular reference is removed
allowing the convenience libraries to work again.
This is also a stepping block to proving a Suricata library
as a single .a or .so file.
Since the completion status was a constant for all parsers, remove the
callback logic and instead register the values themselves. This should
avoid a lot of unnecessary callback calls.
Update all parsers to take advantage of this.
This parameter is NULL or the pointer to the previous state
for the previous protocol in the case of a protocol change,
for instance from HTTP1 to HTTP2
This way, the new protocol can use the old protocol context.
For instance, HTTP2 mimicks the HTTP1 request, to have a HTTP2
transaction with both request and response
Optional callback a parser can register for applying configuration
to the 'transaction'. Most parsers have a bidirectional tx. For those
parsers that have different types of transaction handling, this new
callback can be used to properly apply the config.
AppLayerTxData is a structure each tx should include that will contain
the common fields the engine needs for tracking logging, detection and
possibly other things.
AppLayerTxConfig will be used by the detection engine to configure
the transaction.
These macros generate the extern "C" functions for transactions
structs that need provide functions for setting and getting
the de_state. The idea is to provide macros do avoid code
duplication and make it simpler to create an app-layer.
A trait would be the correct solution, but it doesn't look like
you can use traits to export extern "C" functions.
Until now, the transaction space is assumed to be terse. Transactions
are handled sequentially so the difference between the lowest and highest
active tx id's is small. For this reason the logic of walking every id
between the 'minimum' and max id made sense. The space might look like:
[..........TTTT]
Here the looping starts at the first T and loops 4 times.
This assumption isn't a great fit though. A protocol like NFS has 2 types
of transactions. Long running file transfer transactions and short lived
request/reply pairs are causing the id space to be sparse. This leads to
a lot of unnecessary looping in various parts of the engine, but most
prominently: detection, tx house keeping and tx logging.
[.T..T...TTTT.T]
Here the looping starts at the first T and loops for every spot, even
those where no tx exists anymore.
Cases have been observed where the lowest tx id was 2 and the highest
was 50k. This lead to a lot of unnecessary looping.
This patch add an alternative approach. It allows a protocol to register
an iterator function, that simply returns the next transaction until
all transactions are returned. To do this it uses a bit of state the
caller must keep.
The registration is optional. If no iterator is registered the old
behaviour will be used.
Avoid looping in transaction output.
Update app-layer API to store the bits in one step
and retrieve the bits in a single step as well.
Update users of the API.
Shivani Bhardwaj
Philippe Antoine
Jason Ish
Victor Julien
Jason Ish
Pierre Chifflier