StreamIterator implementation for iterating over ACKed segments.
Flag each segment as logged when the log function has been called for it.
Set a 'OPEN' flag for the first segment in both directions.
Set a 'CLOSE' flag when the stream ends. If the last segment was already
logged, a empty CLOSE call is performed with NULL data.
For netflow logging track TCP flags per stream direction. As the struct
had no more space left without expanding it, the flags and wscale
fields are now compressed.
Implement StreamTcpSetDisableRawReassemblyFlag() which stops raw
reassembly for _NEW_ segments in a stream direction.
It is used only by TLS/SSL now, to flag the streams as encrypted.
Existing segments will still be reassembled and inspected, while
new segments won't be. This allows for pattern based inspection
of the TLS handshake.
Like is the case with completely disabled 'raw' reassembly, the
logic is that the segments are flagged as completed for 'raw' right
away. So they are not considered in raw reassembly anymore.
As no new segments will be considered, the chunk limit check will
return true on the next call.
Raw reassembly is used only by the detection engine. For users only
caring about logging it's a significant overhead, both in cpu and
memory usage.
The option is called 'raw' and lives under the stream.reassembly
options.
stream:
memcap: 32mb
checksum-validation: yes # reject wrong csums
inline: auto # auto will use inline mode in IPS mode, yes or no set it statically
reassembly:
memcap: 64mb
depth: 1mb # reassemble 1mb into a stream
toserver-chunk-size: 2560
toclient-chunk-size: 2560
randomize-chunk-size: yes
#randomize-chunk-range: 10
raw: false # <- new option
In case of recursive call to protocol detection from within protocol
detection, and the recursively invoked stream still hasn't been ack'ed
yet, protocol detection doesn't take place. In such cases we will end up
still calling the app layer with the wrong direction data. Introduce a
check to not call app layer with wrong direction data.
When sockets are re-used reset all relevant vars correctly.
This commit fixes a bug where we were not reseting app proto detection
vars.
While fixing #989, we discovered some other bugs which have also been
fixed, or rather some features which are now updated. One of the feature
update being if we recieve wrong direction data first, we don't reset the
protocol values for the flow. We let the flow retain the detected
values.
Unittests have been modified to accomodate the above change.
Use per thread pools to store and retrieve SSN's from. Uses PoolThread
API.
Remove max-sessions setting. Pools are set to unlimited, but TCP memcap
limits the amount of sessions.
The prealloc_session settings now applies to each thread, so lowered the
default from 32k to 2k.
Until now, when processing the TCP 3 way handshake (3whs), retransmissions
of SYN/ACKs are silently accepted, unless they are different somehow. If
the SEQ or ACK values are different they are considered wrong and events
are set. The stream events rules will match on this.
In some cases, this is wrong. If the client missed the SYN/ACK, the server
may send a different one with a different SEQ. This commit deals with this.
As it is impossible to predict which one the client will accept, each is
added to a list. Then on receiving the final ACK from the 3whs, the list
is checked and the state is updated according to the queued SYN/ACK.
Ssn flag STREAMTCP_FLAG_ZERO_TIMESTAMP was used in stream only. Due to
it's value it did not conflict with a real stream flag. Renamed it to
STREAMTCP_STREAM_FLAG_ZERO_TIMESTAMP.
The STREAMTCP_FLAG_TIMESTAMP flag is a ssn flag, however it was used in
the stream flag field. As it has the same value as
STREAMTCP_STREAM_FLAG_DEPTH_REACHED it's possible that stream reassembly
got confused by the timestamp.
Removal of per flow 'aldata' array. It contained a ptr for each ALPROTO. Instead now we have 2 ptrs in the flow: alparser and alstate.
Various cleanups and dead code removal from the app layer API.
Should safe 100+ bytes memory per flow on 64 bit.
Updated lots of unittests to reflect these changes.
Split stream reassembly in 2 parts: a part that sends ack'd data to the app
layer parsers as soon as it's available, and another part that queues up
data into larger chunks for raw inspection.