Open_Ultra_SAST/.kiro/specs/corpus-seeded-mechanisms/tasks.md

Implementation Plan

• 1. Foundation: shapes and store fields

• 1.1 Define structural shapes and derive them from a pair

  • Shape with language, sink name, arity, source positions and kinds, closed guard kind, mechanism id; derive_shape finds the labeled sink call site in the vulnerable FileIR, traces source positions through binds to a fact source, parameter, or container read, and classifies the guard from statements present only on the fixed side.
  • Shapes contain no path, line, or literal beyond identifiers.
  • Observable: a Python pair (request input into os.system, fix adds an allowlist) yields sink system, arity 1, source position 0, guard allowlist_test; an unlabeled sink returns None; the shape key is stable across runs.
  • Requirements: 2.1, 2.2, 2.3, 2.4
  • Boundary: Shape

• 1.2 Add additive mechanism fields and a corpus writer with dedupe

  • Mechanism gains origin, review_tier, pairs, shape, guard with defaults; append_from_pair dedupes by shape key and extends provenance; old JSONL rows load unchanged.
  • Observable: appending the same shape from two pairs yields one row listing both pairs; a pre-existing sandbox row loads with origin = "sandbox".
  • Requirements: 1.3, 1.4
  • Boundary: Store
  • Depends: 1.1

• 2. Core: export and search

• 2.1 Export mechanisms from trusted pairs as a maintainer command

  • Only seeded and reviewed, non-known-limit, parse-ok pairs seed; the command runs offline over the vendored catalog and reports skipped pairs with reasons; extra-absent languages are skipped with a degradation.
  • Observable: ousast mechanisms export --slice sast writes corpus rows and reports the skipped title/advisory/known-limit pairs.
  • Requirements: 1.1, 1.2, 1.5, 2.5
  • Boundary: Export
  • Depends: 1.2

• 2.2 Search a tree for variants and merge with overlay flows

  • For each parsed file within the MAP budget, call sites matching a shape's sink name, arity, and source positions (fact source, parameter, container read) produce variant findings at suspicion with the mechanism id; when the overlay has a flow at the same call site, its record gains mechanism_id and no duplicate finding is emitted.
  • Observable: the split-sink Python fixture yields a variant finding merged into the overlay coverage record; a constant-argument call does not match; quick emits no variants.
  • Requirements: 3.1, 3.2, 3.3, 3.6
  • Boundary: VariantSearch
  • Depends: 2.1

• 2.3 Make variant findings sandbox-eligible and count them in the manifest

  • Variant findings enter the candidate set after overlay promotions under the existing safety check and caps; the manifest records mechanisms searched, files searched, findings, and merges.
  • Observable: with the fake sandbox a variant finding runs; the manifest variants block is present on standard scans and absent on quick.
  • Requirements: 3.4, 3.5, 6.2
  • Depends: 2.2

• 3. Measurement: leave-one-out

• 3.1 Evaluate the corpus leave-one-out

  • For each trusted pair, seed a temporary store from the others, search both excerpts, and score detection and silence with the pair rules; report per slice, profile, mechanism, and per pair which mechanism found it; write loo.json.
  • Observable: ousast pairs --slice vibe-py --loo --json reports recall, silence, Youden per slice/profile/mechanism and found_by per pair; the run is offline.
  • Requirements: 4.1, 4.2, 4.3, 4.4
  • Boundary: LOO
  • Depends: 2.2

• 3.2 Record the leave-one-out baseline

  • Roadmap gains a leave-one-out table per slice next to the pair baselines; not a gate.
  • Observable: roadmap table present; gates unchanged.
  • Requirements: 4.4, 7.2
  • Depends: 3.1

• 4. Integration: improve lever

• 4.1 Add the mechanisms lever with a closed validator

  • MechanismEdit admit/retract by record id from the exporter's candidate set; validator rejects free-form shapes and unknown guard kinds; journal records pair provenance and metrics.
  • Observable: a free-form edit is rejected; an admit edit of an exported record passes validation and appears in the journal.
  • Requirements: 5.1, 5.2, 5.5
  • Boundary: Lever
  • Depends: 2.1

• 4.2 Propose admissions from leave-one-out misses and retractions from leaks under the existing gate

  • Admit candidates that recover a currently missed holdout pair; retract admitted records that leak on holdout fixed sides; existing accept gate and per-profile clause decide; rejection reverts the store byte for byte.
  • Observable: a scripted candidate that recovers a holdout pair is accepted and persisted; one that leaks on a fixed side is rejected and the store is unchanged.
  • Requirements: 5.3, 5.4
  • Depends: 4.1, 3.1

• 5. Integration: reports

• 5.1 Show mechanism id, known fix guard, and provenance on findings

  • Markdown and SARIF show mechanism summary, guard shape, and pair provenance for findings carrying a mechanism id; variant findings are labeled suspicions unless raised.
  • Observable: a standard scan report on the split-sink fixture names the mechanism and its guard; SARIF properties carry the id.
  • Requirements: 6.1, 6.3
  • Depends: 2.2

• 6. Validation

• 6.1 Prove offline tests and unchanged gates

  • Unit and integration tests run without network, model, or sandbox; semantic-marked tests skip without the extra; detection, map, and local pair gates unchanged; extra-free suite green.
  • Observable: both pytest matrices green; gate entrypoints unchanged.
  • Requirements: 7.1, 7.2, 7.3
  • Depends: 2.3, 3.1, 4.2, 5.1

Implementation Notes

• Spec approved by the maintainer in session 2026-09-05 ("continue with corpus-seeded-mechanisms"); approvals recorded in spec.json.
• Task 1.1 (2026-09-05, RED first: 5 failing tests in tests/test_variants.py, ModuleNotFoundError: openultrasast.semantic.variants; then green): semantic/variants.py with Shape (language, sink_name, arity, source_positions, source_kinds, guard, mechanism; key()/to_dict()/from_dict() text-free), closed GUARD_KINDS/SOURCE_KINDS, derive_shape(vuln_ir, fixed_ir, *, function, sink, line, mechanism, facts, vuln_text, fixed_text). Deviation from the design signature: the two excerpt texts are passed in because guard statements (if x not in ALLOWED, if len(x) > n) are not call sites or binds in FileIR; the guard kind is classified from the lines of the labeled function that exist only on the fixed side, closed set, none when unknown; nothing of that text enters the shape. Source kinds trace argument identifiers through binds (fact-source pattern -> fact_source; subscript/.get(/request container -> container_read; parameter -> parameter), preferring fact_source, then parameter, then container_read. A constant-only sink call or a missing function/call site yields None.
• Task 1.2 (2026-09-05, RED first: 3 failing tests in tests/test_mechanism_export.py — Mechanism lacked origin, append_from_pair missing; then green): additive Mechanism.origin/review_tier/pairs/shape/guard with defaults so sandbox rows load unchanged; MechanismStore.load() folds the append-only log by id (latest row wins) so a re-seeded shape carries the extended pairs; append_from_pair uses a deterministic id corpus:<sha1(shape.key())[:16]> so the improve lever can name records across machines; corpus_mechanisms() selects searchable rows. Existing order_promotions tests unchanged and green.
• Review round 1 (2026-09-05) APPROVED 1.1 and 1.2 (reviewer re-simulated RED, ran six mutations, verified the import boundary and that sandbox rows load unchanged; isolated suite 493 / 480 green, statics and gates clean). Suggestions carried into group 2: trim _CONTAINER_READ to the design's subscript/.get( definition so no source vocabulary lives outside facts; intersect line and sink in _labeled_call; append_from_pair keeps the highest tier and accumulates provenance tags when a shape is re-seeded; sync design §Shape to the implemented signature.
• Task 2.1 (2026-09-05, RED first: 4 failing tests in tests/test_mechanism_seed.py — ModuleNotFoundError: semantic.seed x3, argparse rejected mechanisms; then green): semantic/seed.py export_mechanisms(cases, store) seeds only seeded|reviewed, non-known-limit, parsing pairs with cached excerpts, skips with reasons (tier:<t>, known_limit:<why>, parse_failed, variants_language_unsupported + degradation, pointer_pair_not_cached, no_labeled_sink_call_site) and keeps catalog order; CLI ousast mechanisms export --slice S [--store P] [--json], default store .openultrasast/calibration/mechanisms.jsonl (the path the scan reads; the store module's DEFAULT_MECHANISM_LOG differs and is left alone). Discovery: vibe-py labels carry a function and a mechanism but no sink or line, so derive_shape gained a facts-driven fallback (the fact-sink call inside the labeled function, CWE-matching and non-constant first) and now intersects line and sink when both exist (round-1 suggestion); _CONTAINER_READ trimmed to subscript/.get(; append_from_pair keeps the highest tier and accumulates provenance tags. Measured export (offline, scratchpad stores): vibe-py 35 pairs -> 16 seeded, 10 records (7 pairs share execute/1 parameter; the 19 skips are absence-class labels — IDOR, open redirect, missing guard — with no sink call to shape); local 3 -> 0 (fixtures label no sink call site); sast 11 and vfc-js 17 -> 0, all tier:advisory as Req 1.2 requires. Guards are mostly none because Real-Vuln fixed twins are separate trap functions, not patched code.
• Task 2.2 (2026-09-05, RED first: 3 failing tests in tests/test_variant_search.py, ImportError: match_shapes|VariantHit|search_tree; then green): variants.match_shapes(ir, shapes, facts, mechanism_ids=) matches trailing callee name + arity and requires every shape source position to carry a source of any kind (a shape learned from request.args fires on a parameter); constants and arity mismatches never match. New module semantic/variant_search.py (design deviation: the file plan put search_tree/hits_to_findings in variants.py, but they need the store, the overlay records and StaticFinding, which variants.py must not import): search_tree(root, targets, store, facts, max_mechanisms) -> SearchResult(hits, mechanisms_searched, files_searched, degradations); hits_to_findings merges a hit into an overlay promote/coverage record at the same path and line (mechanism_id set, no duplicate) and otherwise emits variant:<id>:<path>:<line> at suspicion with tags variant, mechanism:<id> and the pair provenance in the rationale. OverlayRecord.mechanism_id added (additive).
• Task 2.3 (2026-09-05, RED first: 3 of 4 tests in tests/test_variant_scan.py failing — no variant finding, no overlay merge, variant not offered to the sandbox; the quick-mode test passed trivially and guards the invariant; then green): [variants] enabled=true, max_mechanisms=500 config; MAP runs _search_variants after the overlay (standard/deep only; skipped when facts fail to load), appends variant findings, rewrites overlay.json with merged ids, and the manifest carries variants = {mechanisms_searched, files_searched, findings, merged_into_overlay}; in REGRESS variant findings join the candidate list after the promotions with a zero-score hotspot each, under the same safety check and cap. Verified with the fake sandbox: a variant of a project-specific sink with no inventory rule is offered. Suite 504 passed / 4 skipped, extra-free 491 / 17, statics clean, three gates PASS.
• Task 3.1 (2026-09-05, RED first: 3 failing tests in tests/test_loo.py — ModuleNotFoundError: semantic.loo x2, pairs --loo unknown flag; the two API tests went green on the first implementation): semantic/loo.py evaluate_loo(cases) holds every scorable pair out once (known_limit and uncached pointer pairs skipped with a reason), seeds a temporary store from the other seeded|reviewed pairs (advisory/title pairs are scored as targets, never teach), materializes both sides, runs search_tree, and scores: detected when a hit lies inside the labeled function and names the labeled mechanism or sink; silent when the fixed side yields no hit; found_by lists the record id and the pairs that taught it; metrics (pairs, detected, silent, recall, silence, Youden, teaching) per slice, profile and mechanism; to_dict() is the loo.json artifact. Shape derivation is duplicated from seed.py (_lessons) pending a shared helper once group 2 is accepted. First measurement, vibe-py vendored (35 pairs, 1.0 s): 11 detected (recall 0.314), 21 silent (0.600), Youden -0.086, 16 teaching pairs; per mechanism source_reaches_sink 27 pairs 9 detected / 19 silent, missing_auth_guard 4 / 2 / 2, permissive_default 3 / 0 / 0, path_join_user_input 1 / 0 / 0. The 14 leaks are the coarse execute/1 parameter shape firing on Real-Vuln's false-positive trap twins: the honest over-match rate the mechanisms lever (group 4) retracts on.
• Review round 2 (2026-09-05) APPROVED 2.1, 2.2, 2.3 (reviewer re-simulated all three REDs, killed 11 of 12 mutants, ran the export offline in a network namespace and reproduced the counts, confirmed gates byte-identical to HEAD; judged the zero-score-hotspot candidate path a closer fit to Req 3.4 than the forced path). Suggestions carried into round 3: a test that a hit on a demote/no-flow overlay record is not merged (the surviving mutant); search_tree skips a malformed store row with variants_store_row_invalid instead of aborting the scan; design §VariantSearch/§Modified Files synced (SearchResult, regress/candidate.py untouched); _load_variants uses _int_value; the exporter passes line and sink together; no_labeled_function skip reason; one shared hotspot_from_finding helper.
• Seeding reads PairCase.review_tier from pair-corpus-honesty task 8.1; until it lands, sast and vibe-py rows default to advisory/seeded per that design and only vibe-py seeds.
• Guard classification is heuristic and closed; none is allowed and reported, never used to demote.