This is a DHCP decoder and logger written in Rust. Unlike most
parsers, this one is stateless so responses are not matched
up to requests by Suricata. However, the output does contain
enough fields to match them up in post-processing.
Rules are included to alert of malformed or truncated options.
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.
Don't treat 'external' parsers as more experimental. All parsers
depend on crates to some extend, and all have C glue code. So the
distinction doesn't really make sense.
Add a new parser for Internet Key Exchange version (IKEv2), defined in
RFC 7296.
The IKEv2 parser itself is external. The embedded code includes the
parser state and associated variables, the state machine, and the
detection code.
The parser looks the first two messages of a connection, and analyzes
the client and server proposals to check the cryptographic parameters.
When skipping records the skip tracker could underflow if the record
parsing had more data than expected.
Enforce the calculation by moving it into a method and make the actual
fields private.
parse_smb2_response_read()/parse_smb2_response_write() can be called on
incomplete data, so they didn't use the read/write length field to grab
the data field. Instead it just used rest(). However in some cases
SMB2 records have trailing data, which would be included in the
READ/WRITE data.
This patch addresses this by using the length field if enough data is
available.
Improve ntlmssp version extraction and logging, make its data structures
optional. Extract native os/lm from smb1 ssn setup.
Move session setup handling into their own files.
Only log auth data for the session setup tx.
Implement SMB app-layer parser for SMB1/2/3. Features:
- file extraction
- eve logging
- existing dce keyword support
- smb_share/smb_named_pipe keyword support (stickybuffers)
- auth meta data extraction (ntlmssp, kerberos5)
The 'debug' feature is enabled if suricata was configured with the
--enabled-debug' flag.
If enabled, the SCLogDebug format and calls the logging function as
usual. Otherwise, this macro is a no-op (similarly to the C code).
Also remove the now useless 'state' argument from the SetTxDetectState
calls. For those app-layer parsers that use a state == tx approach,
the state pointer is passed as tx.
Update app-layer parsers to remove the unused call and update the
modified call.
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.
TFTP parsing and logging written in Rust.
Log on eve.json the type of request (read or write), the name of the file and
the mode.
Example of output:
"tftp":{"packet":"read","file":"rfc1350.txt","mode":"octet"}
READ replies with large data chunks are processed partially to avoid
queuing too much data. When the final chunk was received however, the
start of the chunk would already tag the transaction as 'done'. The
more aggressive tx freeing that was recently merged would cause this
tx to be freed before the rest of the in-progress chunk was done.
This patch delays the tagging of the tx until the final data has been
received.
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.
Add option to put Rust code in non-'--release' mode, preserving
debug symbols.
Until now Suricata would have to be compiled with --enable-debug for
this.
Use expectation to be able to identify connections that are
ftp data. It parses the PASV response, STOR message and the
RETR message to provide extraction of files.
Implementation in Rust of FTP messages parsing is available.
Also this patch changes some var name prefixed by ssh to ftp.
Converting the NTP parser to the new registration method is a simple,
3-steps process:
- change the extern functions to use generic input parameters (functions
in all parsers must share common types to be generic) and cast them
- declare the Parser structure
- remove the C code and call the registration function
Add Rust support for the common interface to declare and register all
parsers.
Add a common structure definition to contain all required elements
required for registering a parser, similar to the C interface.
This also reduces the risk of incorrectly registering a parser: the
compiler prevents omitting required functions from the structure, and
functions (even if external) are type-checked. Optional functions are
explicitly marked.
As the DNS probe just uses the query portion of a response, don't
require there to be as many bytes as specified in the TCP DNS
header. This can occur in large responses where probe is called
without all the data.
Fixes the cases where the app proto is recorded as failed.
Fixes issue:
https://redmine.openinfosecfoundation.org/issues/2169