--- id: AUDIT-WP-0009 type: workplan title: "Evidence-role conformance under Security Layer Model v0.7" domain: infotech repo: audit-core status: ready owner: claude topic_slug: railiance created: "2026-08-29" updated: "2026-08-29" depends_on: - AUDIT-WP-0007 state_hub_workstream_id: "46a96b03-bc08-53b5-9c93-4071adabf734" --- # AUDIT-WP-0009 — Evidence-role conformance under Security Layer Model v0.7 ## Goal Make audit-core dischargeable as the estate's **Evidence engine** under NetKingdom Security Layer Model v0.7 (accepted), and stop it claiming a property its own contract does not permit. Two things drive this workplan. **First, a live overclaim.** `audit_core/postgres_backend.py` returns `tamper_evidence=True` as a constant, while `docs/integrity.md` permits that claim only when a live external chain-head attestation exists. The one attestation on record is 2026-08-16 and nothing renews it. Audit Core is currently telling every sender it has a property whose precondition is unverified — the §9.6 defect it twice corrected in gate-house's doctrine, turned inward. **Second, an obligation audit-core argued for and cannot yet support.** v0.7 §9.6 makes a declared emission cadence a **MUST** for load-bearing sources, with reconciliation or a heartbeat as the required form for low-volume classes. audit-core raised both, moving cadence from SHOULD to MUST. A source cannot declare a cadence to a system with nowhere to put it. Having won the obligation, audit-core owes the surface. Full assessment: `history/2026-08-29-v0.7-alignment-and-scope-assessment.md`. Standard: `net-kingdom/canon/standards/security-layer-model_v0.7.md`, companion `net-kingdom/SECURITY-COMPANION.md`. ## Non-goals Fixed by the statute; not deferred, not ours: - No authorization decision surface, and no approval-validity query (§6, §9.4). - No operative approval state (§9.4). - No WORM, object lock, or ITC-CAP `data.archive` — §16 ruled the stronger-custody gap closed, a different store with a different owner. - Emission atomicity at the source, which is the emitter's obligation (§9.6). ## Tasks ```task id: AUDIT-WP-0009-T01 status: todo priority: high state_hub_task_id: "f545b0e4-8c99-5186-affd-ce9a41209ed7" ``` Make `tamper_evidence` conditional on live attestation state. Derive the flag rather than hard-coding it: the backend reports `True` only when a chain-head attestation exists, verifies against the live chain, and is within a declared freshness window. Stale or absent attestation degrades the claim — it does not leave it standing. Assert the degradation with a test, and state the freshness window in `docs/integrity.md` alongside the two existing preconditions, which today are documented but unenforced. ```task id: AUDIT-WP-0009-T02 status: todo priority: high state_hub_task_id: "6de9945f-4dd1-57dd-898a-f59c35b1df6c" ``` Schedule chain-head attestation so the precondition T01 enforces is normally met. `attest-chain` exists and is operator-run; `deploy/` has no job. Add one, write the attestation to the logical-offsite path already used by `RESOURCE-WP-0002-T06` (`rapp-postgres` / Nextcloud + age) and **not** the Barman prefix, per `docs/integrity.md` — that copy is restored with the table and proves nothing. Record the cadence in `docs/integrity.md`. ```task id: AUDIT-WP-0009-T03 status: todo priority: high state_hub_task_id: "acae6085-ada7-51b2-8dc0-4abac7f7e7b3" ``` Represent the §9.6 evidence kind per source. Add `evidence_kind` (`load-bearing` | `attributive`) to `SenderIdentity` and the sender registration schema, defaulting to `attributive` — a source that has not declared is not silently treated as load-bearing. Where a source declares `attributive` and has deliberately traded away atomicity, carry the declared trade with it, because §9.6 requires the trade be declared where the trail is documented. Prerequisite for T04–T06. ```task id: AUDIT-WP-0009-T04 status: todo priority: high state_hub_task_id: "f36470af-4019-54b2-96d7-e049d867c7db" ``` Heartbeat ingestion and missing-heartbeat findings. The required form for low-volume load-bearing classes, and the only control covering adversarial omission for exactly the rare negative events — revocation, denial, containment — where suppression is most valuable and least visible. Accept a signed *nothing to report* assertion per source and class; raise a finding when an expected heartbeat does not arrive. The point is a positive claim that can itself go missing, which rate monitoring can never produce. ```task id: AUDIT-WP-0009-T05 status: wait priority: medium state_hub_task_id: "382575ca-1801-5a32-a93d-90a8b9c8adbf" ``` Accept and evaluate a declared emission cadence per source, and raise a finding when the stream falls below it. **Waiting on** the §17 emission-cadence declaration schema, which `kings-guard` is drafting and Taxonomy will own; do not invent a competing shape. Cadence covers high-volume streams; T04 covers the low-volume load-bearing case, and the two are complementary rather than alternatives. ```task id: AUDIT-WP-0009-T06 status: todo priority: medium state_hub_task_id: "0a8d6eed-75dd-5aaa-bf86-60be9dadca03" ``` Reconciliation surface: per-source, per-class event counts over a bounded window, readable by the source itself, so an emitter can compare audit-core's count against its own state transitions and treat divergence as a finding. `GH-WP-0002-T04` is the reference instance on the `approval-engine` side; this is its counterpart here. Respect the existing read model — `may_read`, tenant scoping, and no payloads in a counts response. ```task id: AUDIT-WP-0009-T07 status: todo priority: medium state_hub_task_id: "f572dfeb-0d1b-58d6-be83-405125189028" ``` Give stream-completeness findings a home. `/v1/dead-letters` and `/v1/secret-findings` exist; a cadence miss (T05) and a missing heartbeat (T04) have nowhere to surface. INTENT principle 10 already says a degraded audit stream is itself an audit and operations event — the principle is in place and the mechanism is not. Follow the existing findings-surface conventions rather than adding a new shape. ```task id: AUDIT-WP-0009-T08 status: todo priority: medium state_hub_task_id: "f7b513ee-af48-5c5a-a34e-3e9922d29b76" ``` Assert the §9.4 approval-validity prohibition with a negative test. It is currently honoured by absence, which is not the estate's idiom: §6.4 obligation 3 requires a PEP's published stance map equal shipped behaviour *asserted by test*. A prohibition worth stating in `INTENT.md`, `SCOPE.md`, and `layer.yaml` is worth asserting in `tests/`. ```task id: AUDIT-WP-0009-T09 status: todo priority: low state_hub_task_id: "fd4a4ac3-e525-57c1-9179-e0fcd0226913" ``` Register `approval-engine` as a distinct source under §9.4 and `AUDIT-IN-0001`: sender registration, the four event classes (issuance, use, supersession, revocation), tenancy mapping, retention profile, `secret_policy`, and `evidence_kind: load-bearing` from T03. Onboarded under INTENT principle 4 — declared ownership, retention, access, export and evidence policy, not merely events arriving. Not blocking: `approval-engine` is not yet emitting. ```task id: AUDIT-WP-0009-T10 status: todo priority: low state_hub_task_id: "ac3464fd-3df9-51a1-b1f4-3bf3c60e4265" ``` Make the §5 conformance check total. `layer.yaml` declares `tooling_contacts: []`, true under §5 as written — audit-core is an Engine and holds no `key-cape` or OpenBao client. Companion §4 asks that uncatalogued infrastructure be listed anyway, and that carve-out sunsets within two review intervals for a store another layer reads, which `platform-pg` is. List it and the State Hub now. Add a conformance script and test in the shape ops-warden offered estate-wide. ## Acceptance - No custody claim is returned unconditionally where `docs/integrity.md` conditions it, and a stale attestation visibly degrades the claim. - A source can declare its evidence kind, and a load-bearing source can discharge the §9.6 cadence MUST against a real audit-core surface. - A suppressed low-volume load-bearing class produces a finding rather than silence. - The approval-validity prohibition is asserted by test, not by absence. - `layer.yaml` lists every infrastructure contact, catalogued or not, and a test checks it. ## Notes T01 and T02 are separable and T01 is the one that matters: scheduling attestation without making the claim conditional would leave the overclaim in place whenever the job fails, which is precisely the case the claim is supposed to cover. T05's dependency is real and should not be worked around. audit-core argued the cadence obligation up to a MUST; inventing a local cadence shape ahead of the Taxonomy schema would fragment the very interface it asked for.