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Dataset set postmatch 5576 v17 #12959

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catenacyber
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Link to ticket: https://redmine.openinfosecfoundation.org/issues/
https://redmine.openinfosecfoundation.org/issues/5576

Describe changes:

  • detect/dataset: delay set operation after signature full match

SV_BRANCH=OISF/suricata-verify#2093

#12627 needed rebase

The design is :

  • detect: postmatch can run AppLayerTxMatch callbacks (in its own commit)
  • usage of delay_postmatch: buffers using dataset/set are put at the tail of inspections whatever their progress
  • usage of DETECT_ENGINE_INSPECT_SIG_MATCH_MORE_BUF: dataset may return this new case to tell that ok we match on a multi-buffer, but we still want to try all occurrences of a multi-buffer (instead of returning a simple early match)

Will be useful for dataset, when it needs to find a transaction
buffer again.
Buffers can be put at the tail of inspections whatever their progress.

This will allow dataset/set to be inspected in the context of
the final packet matching or not, and thus use the ephemeral
data from DetectThreadCtxGetKeywordThreadCtx
DETECT_ENGINE_INSPECT_SIG_MATCH_MORE_BUF is the new return status
to allow dataset/set to pick all matching and only the matching
buffers in case of a multi-buffer
The set operation of dataset keyword was done even if signature
did not fully match, which is not the expected behavior.
We want dataset to behave like flowbits for instance.

This patch changes the behavior of the dataset keyword to do a
match and a post match for the set operation.
The postmatch retrieves the data, using the list identifier
associated to the buffer for this signature.

This avoids to store the buffer(s), when we do not have a
dedicated storage (per signature and per tx) that can own
and clean arbitrary buffers over multiple packets, in
the case the transaction spans over multiple packets
with different tx progresses for instance.

Thanks to delay_postmatch, the callback DetectDatasetTxMatch
should be called on the last packet taking the final match
decision. At this point, the inspection buffers are cached
and easy to get.
The most complex case is for multi-buffers, where we need
to know which buffers/local_ids matched. We use the ephemeral
storage (lives with one packet detection) provided by
DetectThreadCtxGetKeywordThreadCtx

For multi-buffers, we also return DETECT_ENGINE_INSPECT_SIG_MATCH_MORE_BUF
to indicate that we want to know all the instances which match.

Ticket: OISF#5576
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Information: QA ran without warnings.

Pipeline 25568

@catenacyber catenacyber added the needs rebase Needs rebase to master label May 15, 2025
@catenacyber
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Rebased in #13247

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