We only try to parse a small subset of what is possible in
RFB. Currently we only understand some standard auth schemes
and stop parsing when the server-client handshake is complete.
Since in IPS mode returning an error from the parser causes
drops that are likely uncalled for, we do not want to return
errors when we simply do not understand what happens in the
traffic. This addresses Redmine #5912.
Bug: #5912.
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.
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
Every transaction has an existing mandatory field, tx_data. As
DetectEngineState is also mandatory, include it in tx_data.
This allows us to remove the boilerplate every app-layer has
for managing detect engine state.
Based on the Rust clippy lint that recommends that any public
function that dereferences a raw pointer, mark all FFI functions
that reference raw pointers with build_slice and cast_pointer
as unsafe.
This commits starts by removing the unsafe wrapper inside
the build_slice and cast_pointer macros then marks all
functions that use these macros as unsafe.
Then fix all not_unsafe_ptr_arg_deref warnings from clippy.
Fixes clippy lint:
https://rust-lang.github.io/rust-clippy/master/index.html#not_unsafe_ptr_arg_deref
All cases of our transmute can be replaced with more idiomatic
solutions and do no require the power of transmute.
When returning an object to C for life-time management, use
Box::into_raw to convert the boxed object to pointer and use
Box::from_raw to convert back.
For cases where we're just returning a pointer to Rust managed
data, use a cast.
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.
This commit adds an updated incomplete handling for the RFB-Parser. If
incomplete data is processed, the successfully consumed position and
length of remainder + 1 is returned. If the next packet is not empty
suricata will call the parser again.
This commit is a result of discussion on https://github.com/OISF/suricata/pull/4792.
Addresses #3570 by extra checking of calculated size requests.
With the given input, the parser eventually arrived at
parser::parse_failure_reason() which parsed from the remaining four
bytes (describing the string length) that the failure string to follow
would be 4294967295 bytes long. While calculating the total size of the
data to request via AppLayerResult::incomplete(), adding the four bytes
for the parsed but not consumed string length caused the u32 length to
overflow, resulting in a much smaller value triggering the bug condition.
This problem was addressed by more careful checking of values in each step
that could overflow: one subtraction, one addition (which could overflow
the usize length values), and a final check to determine whether the result
still fit into the u32 values required by AppLayerResult::incomplete().
If so, we would safely convert the values and pass them to the result type.
If not, we simply return AppLayerResult::err() but do not erroneously and
silently request the wrong amount.
This commit adds support for the Remote Framebuffer Protocol (RFB) as
used, for example, by various VNC implementations. It targets the
official versions 3.3, 3.7 and 3.8 of the protocol and provides logging
for the RFB handshake communication for now. Logged events include
endpoint versions, details of the security (i.e. authentication)
exchange as well as metadata about the image transfer parameters.
Detection is enabled using keywords for:
- rfb.name: Session name as sticky buffer
- rfb.sectype: Security type, e.g. VNC-style challenge-response
- rfb.secresult: Result of the security exchange, e.g. OK, FAIL, ...
The latter could be used, for example, to detect brute-force attempts
on open VNC servers, while the name could be used to map unwanted VNC
sessions to the desktop owners or machines.
We also ship example EVE-JSON output and keyword docs as part of the
Sphinx source for Suricata's RTD documentation.
Sascha Steinbiss
Philippe Antoine
Haleema Khan
Jason Ish
Victor Julien
Victor Julien
Pierre Chifflier
Sam Muhammed
Shivani Bhardwaj
frank honza