The det_ctx structure was inflated by the additoin of the array to
handle JSON context. This commit updates the code to use a growing
buffer and limit the impact.
This also exposed a difference between the handling of TD alerts in
firewall vs non-firewall mode. In firewall mode the table/hook is also
part of the alert ordering to make sure actions from packet:td are
applied before app:td. Handle that explicitly for now.
Allow keywords to specify in which detect table they can function.
E.g. the pre_flow table will not support flow keywords, as no flow is
availble at this time.
Introduce DetectGetSingleData which does the generic wrapping,
including the transforms, using a new callback prototype
DetectTxGetBufferPtr
The goal is to replace most InspectionBufferGetDataPtr.
For this commit, we do not change every callback to keep the
change relatively small.
Focus here is to remove DetectHelperGetData as its functionality is
provided more directly by the new DetectTxGetBufferPtr.
Ticket: 5634
Allows to share the same validator functions when only the buffer
id is changing like for urilen, while still accessing the buffer
name for error logs
git grep -A 1 -w InspectionBufferSetup shows many cases of the following
call patterns:
- InspectionBufferSetup
- InspectionBufferApplyTransforms
Refactor the implementations of those functions into
InspectionBufferSetupAndApplyTransforms to reduce function call count.
Issue: 2290 (related to changed for this issue)
Ticket: 6575
Multi buffers keywords now use a single registration function
DetectAppLayerMultiRegister with a GetBuffer argument.
This GetBuffer function pointer is similar to the ones used by
single-buffer keyword, except that it takes an additional
parameter which is the index of the buffer to get.
Under the hood, an anonymous union between these 2 functions
pointers types is used.
In the end, this deduplicates code, especially the calls to
DetectEngineContentInspection
Include guards for libraries should use a prefix that is meaningful for
the library to avoid conflicts with other user code. For Suricata, use
SURICATA.
Additionally, remove the pattern of leading and trailing underscores as
these are reserved for the language implementation per the C and C++
standards.
Rename DetectAppLayerInspectEngineRegister2 to
DetectAppLayerInspectEngineRegister as there is no other variant of
this function, and the versioning with lack of supporting
documentation can lead to confusion.
Instead of using flags to indicate a rule type, use an explicit `type`
field.
This will make it more clean in code paths what paths a rule is taking,
and will allow easier debugging as well as analyzer output.
Define the following fields:
- SIG_TYPE_IPONLY: sig meets IP-only criteria and is handled by the IP-only
engine.
- SIG_TYPE_PDONLY: sig inspects protocol detection results only.
- SIG_TYPE_DEONLY: sig inspects decoder events only.
- SIG_TYPE_PKT: sig is inspected per packet.
- SIG_TYPE_PKT_STREAM: sig is inspected against either packet payload or
stream payload.
- SIG_TYPE_STREAM: sig is inspected against the reassembled stream
- SIG_TYPE_APPLAYER: sig is inspected against an app-layer property, but not
against a tx engine.
- SIG_TYPE_APP_TX: sig is inspected the tx aware inspection engine(s).
Ticket: #6085.
Multi buffer matching is implemented as a way for a rule to match
on multiple buffers within the same transaction.
Before this patch a rule like:
dns.query; content:"example"; dns.query; content:".com";
would be equivalent to:
dns.query; content:"example"; content:".com";
If a DNS query would request more than one name, e.g.:
DNS: [example.net][something.com]
Eeach would be inspected to have both patterns present. Otherwise,
it would not be a match. So the rule above would not match, as neither
example.net and somthing.com satisfy both conditions at the same time.
This patch changes this behavior. Instead of the above, each time the
sticky buffer is specified, it creates a separate detection unit. Each
buffer is a "multi buffer" sticky buffer will now be evaluated against
each "instance" of the sticky buffer.
To continue with the above example:
DNS: [example.net] <- matches 'dns.query; content:"example";'
DNS: [something.com] <- matches 'dns.query; content:".com"'
So this would now be a match.
To make sure both patterns match in a single query string, the expression
'dns.query; content:"example"; content:".com";' still works for this.
This patch doesn't yet enable the behavior for the keywords. That is
done in a follow up patch.
To be able to implement this the internal storage of parsed rules
is changed. Until this patch and array of lists was used, where the
index was the buffer id (e.g. http_uri, dns_query). Therefore there
was only one list of matches per buffer id. As a side effect this
array was always very sparsely populated as many buffers could not
be mixed.
This patch changes the internal representation. The new array is densely
packed:
dns.query; content:"1"; dns.query; bsize:1; content:"2";
[type: dns_query][list: content:"1";]
[type: dns_query][list: bsize:1; content:"2";]
The new scheme allows for multiple instances of the same buffer.
These lists are then translated into multiple inspection engines
during the final setup of the rule.
Ticket: #5784.
Instead of a map that is constantly realloc'd, use 2 hash tables for
DetectBufferType entries: one by name (+transforms), the other by
id. Use these everywhere.
DetectEngineReloadThreads does not work for the fuzz targets
as there is no_of_detect_tvs = 0 as we did not register
real threads and slots.
So, we force the flow worker module to use the newly detect engine
conetxt with all it needs
Fix multi inspect buffer API causing cleanup logic in the single
inspect buffer paths. This could lead to a buffer overrun in the
"to clear" logic.
Multi buffers now use InspectionBufferSetupMulti instead of
InspectionBuffer. This is enforced by a check in debug validation.
Simplify the multi inspect buffer setup code and update the callers.
In some cases, the InspectionBufferGet function would be followed by
a failure to set the buffer up, for example due to a HTTP body limit
not yet being reached. Yet each call to InspectionBufferGet would lead
to the matching list_id to be added to the
DetectEngineThreadCtx::inspect.to_clear_queue. This array is sized to
add each list only once, but in this case the same id could be added
multiple times, potentially overflowing the array.