As found by -Wshorten-64-to-32 warnings
Ticket: #6186
Use SCTime_t instead of u32, which increases memory usage for
the structures changed here, while making it more correct.
This callback will be called when alert action has been changed due to a
rate filter. The user can then reset or customize the action in their
callback per their own logic.
As the callback is added to the current detection engine, make sure its
copied to the new detection engine on reload.
Ticket: #7673
Issue: 6855: Match sigmatch type field in var and bit structs
Align the size and datatype of type, idx, and next members across:
- FlowVarThreshold
- FlowBit
- FlowVar
- GenericVar
- XBit
- DetectVarList
Note that the FlowVar structure has been intentionally constrained to
match the structure size prior to this commit. To achieve this, the
keylen member was restricted to 8 bits after it was confirmed its value
is checked against a max of 0xff.
Implement new `type backoff` for thresholding. This allows alerts to be
limited.
A count of 1 with a multiplier of 10 would generate alerts for matching packets:
1, 10, 100, 1000, 10000, 100000, etc.
A count of 1 with a multiplier of 2 would generate alerts for matching packets:
1, 2, 4, 8, 16, 32, etc.
Like with other thresholds, rule actions like drop and setting of
flowbits will still be performed for each matching packet.
Current implementation is only for the by_flow tracker and for per rule
threshold statements.
Tracking is done using uint32_t. When it reaches this value, the rest of
the packets in the tracker will use the silent match.
Ticket: #7120.
Instead of a Host and IPPair table thresholding layer, use a dedicated
THash to store both. This allows hashing on host+sid+tracker or
ippair+sid+tracker, to create more unique hash keys.
This allows for fewer hash collisions.
The per rule tracking also uses this, so that the single big lock is no
longer a single point of contention.
Reimplement storage for flow thresholds to reuse as much logic as
possible from the host/ippair/rule thresholds.
Ticket: #426.
Thresholding often has 2 stages:
1. recording matches
2. appling an action, like suppress
E.g. with something like:
threshold:type limit, count 10, seconds 3600, track by_src;
the recording state is about counting 10 first hits for an IP,
then followed by the "suppress" state that might last an hour.
By_src/by_dst are expensive, as they do a host table lookup and lock
the host. If many threads require this access, lock contention becomes
a serious problem.
This patch adds a thread local cache to avoid the synchronization
overhead. When the threshold for a host enters the "apply" stage,
a thread local hash entry is added. This entry knows the expiry
time and the action to apply. This way the action can be applied
w/o the synchronization overhead.
A rbtree is used to handle expiration.
Implemented for IPv4.
Add support for 'by_flow' track option. This allows using the various
threshold options in the context of a single flow.
Example:
alert tcp ... stream-event:pkt_broken_ack; \
threshold:type limit, track by_flow, count 1, seconds 3600;
The example would limit the number of alerts to once per hour for
packets triggering the 'pkt_broken_ack' stream event.
Implemented as a special "flowvar" holding the threshold entries. This
means no synchronization is required, making this a cheaper option
compared to the other trackers.
Ticket: #6822.
Issue: 5718
This commit switches the majority of time handling to a new type --
SCTime_t -- which is a 64 bit container for time:
- 44 bits -- seconds
- 20 bits -- useconds
Update DROP action handling in tunnel packets. DROP/REJECT action is set
to outer (root) and inner packet.
Check action flags both against outer (root) and inner packet.
Remove PACKET_SET_ACTION macro. Replace with RESET for the one reset usecase.
The reason to remove is to make the logic easier to understand.
Reduce scope of RESET macros.
Rename PacketTestAction to PacketCheckAction except in unittests. Keep
PacketTestAction as a wrapper around PacketCheckAction. This makes it
easier to trace the action handling in the real code.
Fix rate_filter setting actions directly.
General code cleanups.
Bug: #5571.
Bug 5458 states that the reject action is no longer working. While SV
tests that use the reject action still pass, it indeed seems that a
regression has happened with commit aa93984, because while the
function that applies rule actions to the flow (RuleActionToFlow) does
check for the reject action, the newly added function PacketApply
SignatureActions only checks for ACTION_DROP or ACTION_PASS when
deciding to call RuleActionToFlow.
Bug #5458
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
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.
ThresholdHandlePacketRule may take ownership of an allocated
DetectThresholdEntry, and places it in a position of the
array th_entry. But it never got released
th_entry is resized using ThresholdHashRealloc() every time a rule with
a threshold using by_rule tracking is added. The problem is that this is
done before the rules are reordered, so occasionally a rule with by_rule
tracking gets a higher signature number (after reordering) than the
number of th_entries allocated, causing Suricata to crash.
This commit fixes this by allocating th_entries after all the rules are
loaded and reordered.
Backtrace from core dump:
Program terminated with signal SIGSEGV, Segmentation fault.
#0 0x000000000051b381 in ThresholdHandlePacket (p=p@entry=0x7fb0080f3960, lookup_tsh=0x51, new_tsh=new_tsh@entry=0x7fb016c316e0, td=td@entry=0x14adedf0, sid=9800979, gid=1, pa=0x7fb0080f3b18)
at detect-engine-threshold.c:415
415>---- if (TIMEVAL_DIFF_SEC(p->ts, lookup_tsh->tv1) < td->seconds) {
Bug #4503.
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.
Ensure that the by_rule threshold table is initialized if a rule
is thresholded by_rule. Replace manual table reallocaton with calls
to the common function.
The only difference between threshold calculations for by_src/by_dst,
by_rule or by_both is which table stores the DetectThresholdEntry.
Refactor the ThresholdHandlePacket* functions to do table lookup and
storage individually, but calculate thresholds in a common function.
The flow manager thread (that also runs the host cleanup code) would
sometimes free a host before it's thresholds are timed out. This would
lead to misdetection or too many alerts.
This was mostly (only?) visible on slower systems. And was caused by a
mismatch between time concepts of the async flow manager thread and the
packet threads, resulting in the flow manager using a timestamp that
was before the threshold entry creation ts. This would lead to an
integer underflow in the timeout check, leading to a incorrect conclusion
that the threshold entry was timed out.
To address this, check if the 'check' timestamp is not before the creation
timestamp.