Add thread local cache to avoid locking overhead for ssns and segments.
A thread will return segments/ssns to a local cache first, and if that
is full, to a return queue where the actual return to the pool returns
a batch, to amortize locking overhead.
Adds segment and session pool/cache counters to see where how effective
the cache is.
This allows to set a midstream-policy that can:
- fail closed (stream.midstream-policy=drop-flow)
- fail open (stream.midstream-policy=pass-flow)
- bypass stream (stream.midstream-policy=bypass)
- do nothing (default behavior)
Usage and behavior:
If stream.midstream-policy is set then if Suricata identifies a midstream flow
it will apply the corresponding action associated with the policy.
No setting means Suricata will not apply such policies, either inspecting the
flow (if stream.midstream=true) or ignoring it stream.midstream=false.
Task #5468
A Packet may be dropped due to several different reasons. This change
adds action as a parameter, so we can update the packet action when we
drop it, instead of setting it to drop.
Related to
Bug #5458
Bugfix, segment traversal was being initialized at root node, but
should have been started at the min node. Bug resulted in captures
missing segments left of root node.
This avoids long lasting inactive flows because in the most likely
case the RST did in fact end the connection. However Suricata may
still consider it to be "established".
For connections that use TCP timestamps for which the first SYN packet
does not reach the server, any replies to retransmitted SYNs will be
tropped.
This is happening in StateSynSentValidateTimestamp, where the timestamp
value in a SYN-ACK packet must match the one from the SYN packet.
However, since the server never received the first SYN packet, it will
respond with an updated timestamp from any of the following SYN packets.
The timestamp value inside suricata is not being updated at any time
which should happen. This patch fixes that problem.
Bug: #4376.
Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>
Due to the TIMEVAL_DIFF_SEC calculating the delta into an unsigned
integer, it would underflow to a high positive value leading to
and incorrect result if the packet timestamp was below the timestamp
for the threshold entry. In normal conditions this shouldn't happen,
but in offline mode each thread has its own concept of time which
might differ significantly based on the pcap. In this case the
overflow would be very common.
Changing it to a signed value calculation triggered fuzz undefined
behavior if the packet timeval was very high, so this patch takes a
new approach where it no longer calculates a diff but sets up the
"seconds" value we compare against as a timeval itself, and uses
that to compare.
Fixes: 9fafc1031c ("time: Add TIMEVAL_EARLIER and TIMEVAL_DIFF_SEC macros.")
Fixes: 82dc61f4c3 ("detect/threshold: Refactor threshold calculation to handle by_rule and by_both.")
Uses add `timeradd` specific version where available.
Bug: #5386.
Adds a framework for setting exception policies. These would be called
when the engine reaches some kind of exception condition, like hitting
a memcap or some traffic processing error.
The policy gives control over what should happen next: drop the packet,
drop the packet and flow, bypass, etc.
Implements the policy for:
stream: If stream session or reassembly memcaps are hit call the
memcap policy on the packet and flow.
flow: Apply policy when memcap is reached and no flow could be
freed up.
defrag: Apply policy when no tracker could be picked up.
app-layer: Apply ppolicy if a parser reaches an error state.
All options default to 'ignore', which means the default behavior
is unchanged.
Adds commandline options: add simulation options for exceptions. These
are only exposed if compiled with `--enable-debug`.
Ticket: #5214.
Ticket: #5215.
Ticket: #5216.
Ticket: #5218.
Ticket: #5194.
This patch optionally adds packet header to the TCP segment
and update the for each segment function by changing the
callback.
This patch is based on the work by Scott Jordan <scottfgjordan@gmail.com>
Ticket: #4569
If a FIN+SYN packet is sent, the destination may keep the
connection alive instead of starting to close it.
In this case, a later SYN packet will be ignored by the
destination.
Previously, Suricata considered this a session reuse, and thus
used the sequence number of the last SYN packet, instead of
using the one of the live connection, leading to evasion.
This commit errors on FIN+SYN so that they do not get
processed as regular FIN packets.
Special handling for RST packets if they have an TCP MD5 or AO header option.
The options hash can't be validated. The end host might be able to validate
it, as it can have a key/password that was communicated out of band.
The sender could use this to move the TCP state to 'CLOSED', leading to
a desync of the TCP session.
This patch builds on top of
843d0b7a10 ("stream: support RST getting lost/ignored")
It flags the receiver as having received an RST and moves the TCP state
into the CLOSED state. It then reverts this if the sender continues to
send traffic. In this case it sets the following event:
stream-event:suspected_rst_inject;
Bug: #4710.
Outdated packets are ACK packets w/o data that have an ACK value
lower than our last_ack and also don't have an SACK records that
are new.
This can happen when some packets come in later than others (possibly
due to different paths taken).
Not using a packet for the streaming analysis when a non zero
ACK value and ACK bit was unset was leading to evasion as it was
possible to start a session with a SYN packet with a non zero ACK
value to see the full TCP stream to escape all stream and application
layer detection.
This addresses CVE-2021-35063.
Fixes: fa692df37 ("stream: reject broken ACK packets")
Ticket: #4504.
Replaces all patterns of SCLogError() followed by exit() with
FatalError(). Cocci script to do this:
@@
constant C;
constant char[] msg;
@@
- SCLogError(C,
+ FatalError(SC_ERR_FATAL,
msg);
- exit(EXIT_FAILURE);
Closes redmine ticket 3188.
Victor Julien
Juliana Fajardini
Scott Jordan
Philippe Antoine
Michael Tremer
Jason Ish
Eric Leblond
Philippe Antoine
Victor Julien
Juliana Fajardini
Eric Leblond
Jeff Lucovsky
Ilya Bakhtin
Shivani Bhardwaj