Internals
---------
Suricata's stream engine returns data for inspection to the detection
engine from the stream when the chunk size is reached.
Bug
---
Inspection triggered only in the specified chunk sizes may be too late
when it comes to inspection of smaller protocol specific data which
could result in delayed inspection, incorrect data logged with a transaction
and logs misindicating the pkt that triggered an alert.
Fix
---
Fix this by making an explicit call from all respective applayer parsers to
trigger raw stream inspection which shall make the data available for inspection
in the following call of the stream engine. This needs to happen per direction
on the completion of an entity like a request or a response.
Important notes
---------------
1. The above mentioned behavior with and without this patch is
affected internally by the following conditions.
- inspection depth
- stream depth
In these special cases, the inspection window will be affected and
Suricata may not consider all the data that could be expected to be
inspected.
2. This only applies to applayer protocols running over TCP.
3. The inspection window is only considered up to the ACK'd data.
4. This entire issue is about IDS mode only.
NFS has a classic request response model where each request is mapped to
a corresponding response. Additionally, there's also file tracking and
handling done as a part of these transactions. Appropriate calls to
trigger raw stream inspection have been added on completion of each
request and response.
Task 7026
Bug 7004
Deranged v0.4.1 (a dependency of the time crate) has implemented
PartialOrd for some integer types that conflict with the
implementation in the standard library creating an ambiguity as such
implementation are global. For more info see
https://github.com/jhpratt/deranged/issues/18.
To fix, use "::from" directly, instead of using .into() which is where
we run into amgibuity.
Have bindgen generate bindings for app-layer-protos.h, then use the
generated definitions of AppProto/AppProtoEnum instead if defining
them ourselves.
This header was chosen as its used by Rust, and its a simple header
with no circular dependencies.
Ticket: #7341
To optimize detection, and logging, to avoid going through
all the live transactions when only a few were modified.
Two boolean fields are added to the tx data: updated_tc and ts
The app-layer parsers are now responsible to set these when
needed, and the logging and detection uses them to skip
transactions that were not updated.
There may some more optimization remaining by when we set
both updated_tc and updated_ts in functions returning
a mutable transaction, by checking if all the callers
are called in one direction only (request or response)
Ticket: 7087
truncate fn is only active and used by dcerpc and smb parsers. In case
stream depth is reached for any side, truncate fn is supposed to set the
tx entity (request/response) in the same direction as complete so the
other side is not forever waiting for data.
However, whether the stream depth is reached is already checked by
AppLayerParserGetStateProgress fn which is called by:
- DetectTx
- DetectEngineInspectBufferGeneric
- AppLayerParserSetTransactionInspectId
- OutputTxLog
- AppLayerParserTransactionsCleanup
and, in such a case, StateGetProgressCompletionStatus is returned for
the respective direction. This fn following efc9a7a, always returns 1
as long as the direction is valid meaning that the progress for the
current direction is marked complete. So, there is no need for the additional
callback to mark the entities as done in case of depth or a gap.
Remove all such glue code and callbacks for truncate fns.
Bug 7044
Ticket: 7013
Done consistently for all protocols
This may change some protocols behaviors which failed early
if they found there was not enough data...
error: writing `&Vec` instead of `&[_]` involves a new object where a slice will do
--> src/dns/log.rs:371:29
|
371 | pub fn dns_print_addr(addr: &Vec<u8>) -> std::string::String {
| ^^^^^^^^ help: change this to: `&[u8]`
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
Introduce AppLayerTxData::file_tx as direction(s) indicator for transactions.
When set to 0, its not a file tx and it will not be considered for file
inspection, logging and housekeeping tasks.
Various tx loop optimizations in housekeeping and output.
Update the "file capable" app-layers to set the fields based on their
directional file support as well as on the traffic.
Update APIs to store files in transactions instead of the per flow state.
Goal is to avoid the overhead of matching up files and transactions in
cases where there are many of both.
Update all protocol implementations to support this.
Update file logging logic to account for having files in transactions. Instead
of it acting separately on file containers, it is now tied into the
transaction logging.
Update the filestore keyword to consider a match if filestore output not
enabled.
On the Rust side, a Frame requires a StreamSlice to be created. We can
derive the direction from the StreamSlice removing the need for callers
to provide the direction when operating on the frame.
Instead of a method that is required to return a slice of transactions,
use 2 methods, one to return the number of transactions in the
collection, and another to get a transaction by its index in the
collection.
This allows for the transaction collection to not be a contiguous array
and instead can be a VecDeque, or possibly another collection type that
supports retrieval by index.
Ticket #5278
There should be no remaining data after parsing the partial
RPC record, so don't handle it but instead add a debug validation
bug on.
Successful processing for NFSv3 read/write records returns
AppLayerResult::ok() directly as all data is consumed.
Philippe Antoine
Shivani Bhardwaj
Jason Ish
Victor Julien
Eric Leblond
Gabriel Lima Luz
Kristina Jefferson
Victor Julien
Sam Muhammed