Two reusable bundle-derived lookups that the next two commits build
on:
- mitre_url_for(tid) returns the canonical attack.mitre.org URL by
reading external_references on the cached attack-pattern. Backed
by the existing lru-cached _attack_pattern_by_id so per-call cost
is constant. Handles top-level techniques and sub-techniques
(T1059.004 -> .../techniques/T1059/004).
- GroupRef + groups_using_technique(tid) surface the intrusion-set
reverse index from the loaded bundle: given a technique, return
the MITRE-tracked groups documented as using it. Sorted by
group_id for deterministic responses; lru-cached. Sub-technique
semantics match ATT&CK Navigator (do NOT auto-union with parent).
- decnet/ttp/data/intel_loader._mitre_url_for collapses to a thin
re-export of attack_stix.mitre_url_for; the loader keeps mitre_url
on TechniqueEmission for the eventual STIX export.
- tests/ttp/test_attack_url.py covers both helpers: top-level + sub
URLs, unknown -> None / (), GroupRef immutability + hashability,
deterministic ordering, sub-technique distinct from parent.
The four provider→technique tables (AbuseIPDB cat→techniques,
GreyNoise tag→techniques, ThreatFox threat_type→techniques, plus
the Feodo binary-listed signal) used to live as Final[dict] constants
in intel_lifter.py. Two real problems with that:
1. Drift between rules/ttp/R0054.yaml..R0058.yaml (which declare
the full slate per provider) and the Python dicts (which decide
which slate-member fires per signal). The v2 audit comment in
intel_lifter.py documented that they had silently drifted.
2. No ATT&CK provenance on emissions — the loaded STIX bundle has
rich external_references (canonical attack.mitre.org URLs) that
never surfaced because the lifter had no path back to them.
Mappings now live as YAML at decnet/ttp/data/intel/{provider}.yaml,
validated at load against the loaded ATT&CK bundle, with each entry
enriched by attack_stix._attack_pattern_by_id to attach the canonical
MITRE URL to every emission.
- decnet/ttp/data/intel_loader.py: pydantic-validated schema +
ProviderMapping/Signal/TechniqueEmission frozen dataclasses +
load_provider_mapping(provider) lru-cached.
- Per-technique high_score_threshold inlined into YAML
(collapses the separate _ABUSEIPDB_HIGH_SCORE_GATED dict).
- external_reference field follows the STIX 2.1 external-reference
shape (source_name + url + optional external_id) so the future
STIX/MISP exporter is a direct translation.
- intel_lifter.py: dicts deleted, decision functions read from
ProviderMapping accessors. Decision-flow constants (T1071/T1595
bare-classification fallbacks in _greynoise_decisions) stay in
code — they're not table rows.
- Each emit slot's evidence_extra now carries mitre_url for any
technique resolved in the bundle (every one in practice).
- tests/ttp/test_intel_mappings.py: snapshot equivalence vs the
legacy dicts, high-score gate behavior, every-signal-has-an-
external-reference, every-emission-has-a-mitre-url, negative
paths (unknown technique_id raises AttackBundleError, mismatched
provider field rejected, dir listing matches expected providers).
The YAML schema + mitre_url enrichment lays groundwork for the
future STIX exporter; this commit does NOT build that exporter.
