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			- Added `SchedulerWorkerOptions` class to encapsulate configuration for the scheduler worker. - Introduced `PlannerBackgroundService` to manage the planner loop, fetching and processing planning runs. - Created `PlannerExecutionService` to handle the execution logic for planning runs, including impact targeting and run persistence. - Developed `PlannerExecutionResult` and `PlannerExecutionStatus` to standardize execution outcomes. - Implemented validation logic within `SchedulerWorkerOptions` to ensure proper configuration. - Added documentation for the planner loop and impact targeting features. - Established health check endpoints and authentication mechanisms for the Signals service. - Created unit tests for the Signals API to ensure proper functionality and response handling. - Configured options for authority integration and fallback authentication methods.
		
			
				
	
	
		
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			299 lines
		
	
	
		
			27 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| # StellaOps Authority Service
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| 
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| > **Status:** Drafted 2025-10-12 (CORE5B.DOC / DOC1.AUTH) – aligns with Authority revocation store, JWKS rotation, and bootstrap endpoints delivered in Sprint 1.
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| 
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| ## 1. Purpose
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| The **StellaOps Authority** service issues OAuth2/OIDC tokens for every StellaOps module (Concelier, Backend, Agent, Zastava) and exposes the policy controls required in sovereign/offline environments. Authority is built as a minimal ASP.NET host that:
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| 
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| - brokers password, client-credentials, and device-code flows through pluggable identity providers;
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| - persists access/refresh/device tokens in MongoDB with deterministic schemas for replay analysis and air-gapped audit copies;
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| - distributes revocation bundles and JWKS material so downstream services can enforce lockouts without direct database access;
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| - offers bootstrap APIs for first-run provisioning and key rotation without redeploying binaries.
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| 
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| Authority is deployed alongside Concelier in air-gapped environments and never requires outbound internet access. All trusted metadata (OpenIddict discovery, JWKS, revocation bundles) is cacheable, signed, and reproducible.
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| 
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| ## 2. Component Architecture
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| Authority is composed of five cooperating subsystems:
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| 
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| 1. **Minimal API host** – configures OpenIddict endpoints (`/token`, `/authorize`, `/revoke`, `/jwks`) and structured logging/telemetry. Rate limiting hooks (`AuthorityRateLimiter`) wrap every request.
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| 2. **Plugin host** – loads `StellaOps.Authority.Plugin.*.dll` assemblies, applies capability metadata, and exposes password/client provisioning surfaces through dependency injection.
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| 3. **Mongo storage** – persists tokens, revocations, bootstrap invites, and plugin state in deterministic collections indexed for offline sync (`authority_tokens`, `authority_revocations`, etc.).
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| 4. **Cryptography layer** – `StellaOps.Cryptography` abstractions manage password hashing, signing keys, JWKS export, and detached JWS generation.
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| 5. **Offline ops APIs** – internal endpoints under `/internal/*` provide administrative flows (bootstrap users/clients, revocation export) guarded by API keys and deterministic audit events.
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| 
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| A high-level sequence for password logins:
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| 
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| ```
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| Client -> /token (password grant)
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|   -> Rate limiter & audit hooks
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|   -> Plugin credential store (Argon2id verification)
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|   -> Token persistence (Mongo authority_tokens)
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|   -> Response (access/refresh tokens + deterministic claims)
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| ```
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| 
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| ## 3. Token Lifecycle & Persistence
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| Authority persists every issued token in MongoDB so operators can audit or revoke without scanning distributed caches.
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| 
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| - **Collection:** `authority_tokens`
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| - **Key fields:**
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| - `tokenId`, `type` (`access_token`, `refresh_token`, `device_code`, `authorization_code`)
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| - `subjectId`, `clientId`, ordered `scope` array
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| - `tenant` (lower-cased tenant hint from the issuing client, omitted for global clients)
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| - `status` (`valid`, `revoked`, `expired`), `createdAt`, optional `expiresAt`
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| - `revokedAt`, machine-readable `revokedReason`, optional `revokedReasonDescription`
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| - `revokedMetadata` (string dictionary for plugin-specific context)
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| - **Persistence flow:** `PersistTokensHandler` stamps missing JWT IDs, normalises scopes, and stores every principal emitted by OpenIddict.
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| - **Revocation flow:** `AuthorityTokenStore.UpdateStatusAsync` flips status, records the reason metadata, and is invoked by token revocation handlers and plugin provisioning events (e.g., disabling a user).
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| - **Expiry maintenance:** `AuthorityTokenStore.DeleteExpiredAsync` prunes non-revoked tokens past their `expiresAt` timestamp. Operators should schedule this in maintenance windows if large volumes of tokens are issued.
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| 
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| ### Expectations for resource servers
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| Resource servers (Concelier WebService, Backend, Agent) **must not** assume in-memory caches are authoritative. They should:
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| 
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| - cache `/jwks` and `/revocations/export` responses within configured lifetimes;
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| - honour `revokedReason` metadata when shaping audit trails;
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| - treat `status != "valid"` or missing tokens as immediate denial conditions.
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| - propagate the `tenant` claim (`X-Stella-Tenant` header in REST calls) and reject requests when the tenant supplied by Authority does not match the resource server's scope; Concelier and Excititor guard endpoints refuse cross-tenant tokens.
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| 
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| ### Tenant propagation
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| 
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| - Client provisioning (bootstrap or plug-in) accepts a `tenant` hint. Authority normalises the value (`trim().ToLowerInvariant()`) and persists it alongside the registration. Clients without an explicit tenant remain global.
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| - Issued principals include the `stellaops:tenant` claim. `PersistTokensHandler` mirrors this claim into `authority_tokens.tenant`, enabling per-tenant revocation and reporting.
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| - Rate limiter metadata now tags requests with `authority.tenant`, unlocking per-tenant throughput metrics and diagnostic filters. Audit events (`authority.client_credentials.grant`, `authority.password.grant`, bootstrap flows) surface the tenant and login attempt documents index on `{tenant, occurredAt}` for quick queries.
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| - Client credentials that request `advisory:ingest`, `advisory:read`, `vex:ingest`, `vex:read`, or `aoc:verify` now fail fast when the client registration lacks a tenant hint. Issued tokens are re-validated against persisted tenant metadata, and Authority rejects any cross-tenant replay (`invalid_client`/`invalid_token`), ensuring aggregation-only workloads remain tenant-scoped.
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| - Password grant flows reuse the client registration's tenant and enforce the configured scope allow-list. Requested scopes outside that list (or mismatched tenants) trigger `invalid_scope`/`invalid_client` failures, ensuring cross-tenant access is denied before token issuance.
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| 
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| ### Default service scopes
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| 
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| | Client ID            | Purpose                              | Scopes granted                        | Sender constraint | Tenant          |
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| |----------------------|---------------------------------------|--------------------------------------|-------------------|-----------------|
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| | `concelier-ingest`   | Concelier raw advisory ingestion      | `advisory:ingest`, `advisory:read`   | `dpop`            | `tenant-default` |
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| | `excitor-ingest`     | Excititor raw VEX ingestion           | `vex:ingest`, `vex:read`             | `dpop`            | `tenant-default` |
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| | `aoc-verifier`       | Aggregation-only contract verification | `aoc:verify`, `advisory:read`, `vex:read` | `dpop`            | `tenant-default` |
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| | `cartographer-service` | Graph snapshot construction             | `graph:write`, `graph:read`          | `dpop`            | `tenant-default` |
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| | `graph-api`          | Graph Explorer gateway/API            | `graph:read`, `graph:export`, `graph:simulate` | `dpop` | `tenant-default` |
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| | `vuln-explorer-ui`   | Vuln Explorer UI/API                  | `vuln:read`                          | `dpop`            | `tenant-default` |
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| 
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| > **Secret hygiene (2025‑10‑27):** The repository includes a convenience `etc/authority.yaml` for compose/helm smoke tests. Every entry’s `secretFile` points to `etc/secrets/*.secret`, which ship with `*-change-me` placeholders—replace them with strong values (and wire them through your vault/secret manager) before issuing tokens in CI, staging, or production.
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| 
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| These registrations are provided as examples in `etc/authority.yaml.sample`. Clone them per tenant (for example `concelier-tenant-a`, `concelier-tenant-b`) so tokens remain tenant-scoped by construction.
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| 
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| Graph Explorer introduces dedicated scopes: `graph:write` for Cartographer build jobs, `graph:read` for query/read operations, `graph:export` for long-running export downloads, and `graph:simulate` for what-if overlays. Assign only the scopes a client actually needs to preserve least privilege—UI-facing clients should typically request read/export access, while background services (Cartographer, Scheduler) require write privileges.
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| 
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| #### Least-privilege guidance for graph clients
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| 
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| - **Service identities** – The Cartographer worker should request `graph:write` and `graph:read` only; grant `graph:simulate` exclusively to pipeline automation that invokes Policy Engine overlays on demand. Keep `graph:export` scoped to API gateway components responsible for streaming GraphML/JSONL artifacts. Authority enforces this by rejecting `graph:write` tokens that lack `properties.serviceIdentity: cartographer`.
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| - **Tenant propagation** – Every client registration must pin a `tenant` hint. Authority normalises the value and stamps it into issued tokens (`stellaops:tenant`) so downstream services (Scheduler, Graph API, Console) can enforce tenant isolation without custom headers. Graph scopes (`graph:read`, `graph:write`, `graph:export`, `graph:simulate`) are denied if the tenant hint is missing.
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| - **SDK alignment** – Use the generated `StellaOpsScopes` constants in service code to request graph scopes. Hard-coded strings risk falling out of sync as additional graph capabilities are added.
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| - **DPOP for automation** – Maintain sender-constrained (`dpop`) flows for Cartographer and Scheduler to limit reuse of access tokens if a build host is compromised. For UI-facing tokens, pair `graph:read`/`graph:export` with short lifetimes and enforce refresh-token rotation at the gateway.
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| 
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| #### Vuln Explorer permalinks
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| 
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| - **Scope** – `vuln:read` authorises Vuln Explorer to fetch advisory/linkset evidence and issue shareable links. Assign it only to front-end/API clients that must render vulnerability details.
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| - **Signed links** – `POST /permalinks/vuln` (requires `vuln:read`) accepts `{ "tenant": "tenant-a", "resourceKind": "vulnerability", "state": { ... }, "expiresInSeconds": 86400 }` and returns a JWT (`token`) plus `issuedAt`/`expiresAt`. The token embeds the tenant, requested state, and `vuln:read` scope and is signed with the same Authority signing keys published via `/jwks`.
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| - **Validation** – Resource servers verify the permalink using cached JWKS: check signature, ensure the tenant matches the current request context, honour the expiry, and enforce the contained `vuln:read` scope. The payload’s `resource.state` block is opaque JSON so UIs can round-trip filters/search terms without new schema changes.
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| 
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| ## 4. Revocation Pipeline
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| Authority centralises revocation in `authority_revocations` with deterministic categories:
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| 
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| | Category | Meaning | Required fields |
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| | --- | --- | --- |
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| | `token` | Specific OAuth token revoked early. | `revocationId` (token id), `tokenType`, optional `clientId`, `subjectId` |
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| | `subject` | All tokens for a subject disabled. | `revocationId` (= subject id) |
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| | `client` | OAuth client registration revoked. | `revocationId` (= client id) |
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| | `key` | Signing/JWE key withdrawn. | `revocationId` (= key id) |
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| 
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| `RevocationBundleBuilder` flattens Mongo documents into canonical JSON, sorts entries by (`category`, `revocationId`, `revokedAt`), and signs exports using detached JWS (RFC 7797) with cosign-compatible headers.
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| 
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| **Export surfaces** (deterministic output, suitable for Offline Kit):
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| 
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| - CLI: `stella auth revoke export --output ./out` writes `revocation-bundle.json`, `.jws`, `.sha256`.
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| - Verification: `stella auth revoke verify --bundle <path> --signature <path> --key <path>` validates detached JWS signatures before distribution, selecting the crypto provider advertised in the detached header (see `docs/security/revocation-bundle.md`).
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| - API: `GET /internal/revocations/export` (requires bootstrap API key) returns the same payload.
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| - Verification: `stella auth revoke verify` validates schema, digest, and detached JWS using cached JWKS or offline keys, automatically preferring the hinted provider (libsodium builds honour `provider=libsodium`; other builds fall back to the managed provider).
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| 
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| **Consumer guidance:**
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| 
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| 1. Mirror `revocation-bundle.json*` alongside Concelier exports. Offline agents fetch both over the existing update channel.
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| 2. Use bundle `sequence` and `bundleId` to detect replay or monotonicity regressions. Ignore bundles with older sequence numbers unless `bundleId` changes and `issuedAt` advances.
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| 3. Treat `revokedReason` taxonomy as machine-friendly codes (`compromised`, `rotation`, `policy`, `lifecycle`). Translating to human-readable logs is the consumer’s responsibility.
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| 
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| ## 5. Signing Keys & JWKS Rotation
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| Authority signs revocation bundles and publishes JWKS entries via the new signing manager:
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| 
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| - **Configuration (`authority.yaml`):**
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|   ```yaml
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|   signing:
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|     enabled: true
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|     algorithm: ES256            # Defaults to ES256
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|     keySource: file             # Loader identifier (file, vault, etc.)
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|     provider: default           # Optional preferred crypto provider
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|     activeKeyId: authority-signing-dev
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|     keyPath: "../certificates/authority-signing-dev.pem"
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|     additionalKeys:
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|       - keyId: authority-signing-dev-2024
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|         path: "../certificates/authority-signing-dev-2024.pem"
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|         source: "file"
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|   ```
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| - **Sources:** The default loader supports PEM files relative to the content root; additional loaders can be registered via `IAuthoritySigningKeySource`.
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| - **Providers:** Keys are registered against the `ICryptoProviderRegistry`, so alternative implementations (HSM, libsodium) can be plugged in without changing host code.
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| - **JWKS output:** `GET /jwks` lists every signing key with `status` metadata (`active`, `retired`). Old keys remain until operators remove them from configuration, allowing verification of historical bundles/tokens.
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| 
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| ### Rotation SOP (no downtime)
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| 1. Generate a new P-256 private key (PEM) on an offline workstation and place it where the Authority host can read it (e.g., `../certificates/authority-signing-2025.pem`).
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| 2. Call the authenticated admin API:
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|    ```bash
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|    curl -sS -X POST https://authority.example.com/internal/signing/rotate \
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|      -H "x-stellaops-bootstrap-key: ${BOOTSTRAP_KEY}" \
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|      -H "Content-Type: application/json" \
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|      -d '{
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|            "keyId": "authority-signing-2025",
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|            "location": "../certificates/authority-signing-2025.pem",
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|            "source": "file"
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|          }'
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|    ```
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| 3. Verify the response reports the previous key as retired and fetch `/jwks` to confirm the new `kid` appears with `status: "active"`.
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| 4. Persist the old key path in `signing.additionalKeys` (the rotation API updates in-memory options; rewrite the YAML to match so restarts remain consistent).
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| 5. If you prefer automation, trigger the `.gitea/workflows/authority-key-rotation.yml` workflow with the new `keyId`/`keyPath`; it wraps `ops/authority/key-rotation.sh` and reads environment-specific secrets. The older key will be marked `retired` and appended to `signing.additionalKeys`.
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| 6. Re-run `stella auth revoke export` so revocation bundles are signed with the new key. Downstream caches should refresh JWKS within their configured lifetime (`StellaOpsAuthorityOptions.Signing` + client cache tolerance).
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| 
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| The rotation API leverages the same cryptography abstractions as revocation signing; no restart is required and the previous key is marked `retired` but kept available for verification.
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| 
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| ## 6. Bootstrap & Administrative Endpoints
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| Administrative APIs live under `/internal/*` and require the bootstrap API key plus rate-limiter compliance.
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| 
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| | Endpoint | Method | Description |
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| | --- | --- | --- |
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| | `/internal/users` | `POST` | Provision initial administrative accounts through the registered password-capable plug-in. Emits structured audit events. |
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| | `/internal/clients` | `POST` | Provision OAuth clients (client credentials / device code). |
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| | `/internal/revocations/export` | `GET` | Export revocation bundle + detached JWS + digest. |
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| | `/internal/signing/rotate` | `POST` | Promote a new signing key (see SOP above). Request body accepts `keyId`, `location`, optional `source`, `algorithm`, `provider`, and metadata. |
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| 
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| All administrative calls emit `AuthEventRecord` entries enriched with correlation IDs, PII tags, and network metadata for offline SOC ingestion.
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| 
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| > **Tenant hint:** include a `tenant` entry inside `properties` when bootstrapping clients. Authority normalises the value, stores it on the registration, and stamps future tokens/audit events with the tenant.
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| 
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| ### Bootstrap client example
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| 
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| ```jsonc
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| POST /internal/clients
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| {
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|   "clientId": "concelier",
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|   "confidential": true,
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|   "displayName": "Concelier Backend",
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|   "allowedGrantTypes": ["client_credentials"],
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|   "allowedScopes": ["concelier.jobs.trigger", "advisory:ingest", "advisory:read"],
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|   "properties": {
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|     "tenant": "tenant-default"
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|   }
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| }
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| ```
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| 
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| For environments with multiple tenants, repeat the call per tenant-specific client (e.g. `concelier-tenant-a`, `concelier-tenant-b`) or append suffixes to the client identifier.
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| 
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| ### Aggregation-only verification tokens
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| 
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| - Issue a dedicated client (e.g. `aoc-verifier`) with the scopes `aoc:verify`, `advisory:read`, and `vex:read` for each tenant that runs guard checks. Authority refuses to mint tokens for these scopes unless the client registration provides a tenant hint.
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| - The CLI (`stella aoc verify --tenant <tenant>`) and Console verification panel both call `/aoc/verify` on Concelier and Excititor. Tokens that omit the tenant claim or present a tenant that does not match the stored registration are rejected with `invalid_client`/`invalid_token`.
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| - Verification responses map guard failures to `ERR_AOC_00x` codes and Authority emits `authority.client_credentials.grant` + `authority.token.validate_access` audit records containing the tenant and scopes so operators can trace who executed a run.
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| - For air-gapped or offline replicas, pre-issue verification tokens per tenant and rotate them alongside ingest credentials; the guard endpoints never mutate data and remain safe to expose through the offline kit schedule.
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| 
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| ## 7. Configuration Reference
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| 
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| | Section | Key | Description | Notes |
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| | --- | --- | --- | --- |
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| | Root | `issuer` | Absolute HTTPS issuer advertised to clients. | Required. Loopback HTTP allowed only for development. |
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| | Tokens | `accessTokenLifetime`, `refreshTokenLifetime`, etc. | Lifetimes for each grant (access, refresh, device, authorization code, identity). | Enforced during issuance; persisted on each token document. |
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| | Storage | `storage.connectionString` | MongoDB connection string. | Required even for tests; offline kits ship snapshots for seeding. |
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| | Signing | `signing.enabled` | Enable JWKS/revocation signing. | Disable only for development. |
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| | Signing | `signing.algorithm` | Signing algorithm identifier. | Currently ES256; additional curves can be wired through crypto providers. |
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| | Signing | `signing.keySource` | Loader identifier (`file`, `vault`, custom). | Determines which `IAuthoritySigningKeySource` resolves keys. |
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| | Signing | `signing.keyPath` | Relative/absolute path understood by the loader. | Stored as-is; rotation request should keep it in sync with filesystem layout. |
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| | Signing | `signing.activeKeyId` | Active JWKS / revocation signing key id. | Exposed as `kid` in JWKS and bundles. |
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| | Signing | `signing.additionalKeys[].keyId` | Retired key identifier retained for verification. | Manager updates this automatically after rotation; keep YAML aligned. |
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| | Signing | `signing.additionalKeys[].source` | Loader identifier per retired key. | Defaults to `signing.keySource` if omitted. |
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| | Security | `security.rateLimiting` | Fixed-window limits for `/token`, `/authorize`, `/internal/*`. | See `docs/security/rate-limits.md` for tuning. |
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| | Bootstrap | `bootstrap.apiKey` | Shared secret required for `/internal/*`. | Only required when `bootstrap.enabled` is true. |
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| 
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| ### 7.1 Sender-constrained clients (DPoP & mTLS)
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| 
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| Authority now understands two flavours of sender-constrained OAuth clients:
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| 
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| - **DPoP proof-of-possession** – clients sign a `DPoP` header for `/token` requests. Authority validates the JWK thumbprint, HTTP method/URI, and replay window, then stamps the resulting access token with `cnf.jkt` so downstream services can verify the same key is reused.
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|   - Configure under `security.senderConstraints.dpop`. `allowedAlgorithms`, `proofLifetime`, and `replayWindow` are enforced at validation time.
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|   - `security.senderConstraints.dpop.nonce.enabled` enables nonce challenges for high-value audiences (`requiredAudiences`, normalised to case-insensitive strings). When a nonce is required but missing or expired, `/token` replies with `WWW-Authenticate: DPoP error="use_dpop_nonce"` (and, when available, a fresh `DPoP-Nonce` header). Clients must retry with the issued nonce embedded in the proof.
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|   - `security.senderConstraints.dpop.nonce.store` selects `memory` (default) or `redis`. When `redis` is configured, set `security.senderConstraints.dpop.nonce.redisConnectionString` so replicas share nonce issuance and high-value clients avoid replay gaps during failover.
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|   - Example (enabling Redis-backed nonces; adjust audiences per deployment):
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|     ```yaml
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|     security:
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|       senderConstraints:
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|         dpop:
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|           enabled: true
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|           proofLifetime: "00:02:00"
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|           replayWindow: "00:05:00"
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|           allowedAlgorithms: [ "ES256", "ES384" ]
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|           nonce:
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|             enabled: true
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|             ttl: "00:10:00"
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|             maxIssuancePerMinute: 120
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|             store: "redis"
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|             redisConnectionString: "redis://authority-redis:6379?ssl=false"
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|             requiredAudiences:
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|               - "signer"
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|               - "attestor"
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|     ```
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|     Operators can override any field via environment variables (e.g. `STELLAOPS_AUTHORITY__SECURITY__SENDERCONSTRAINTS__DPOP__NONCE__STORE=redis`).
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|   - Declare client `audiences` in bootstrap manifests or plug-in provisioning metadata; Authority now defaults the token `aud` claim and `resource` indicator from this list, which is also used to trigger nonce enforcement for audiences such as `signer` and `attestor`.
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| - **Mutual TLS clients** – client registrations may declare an mTLS binding (`senderConstraint: mtls`). When enabled via `security.senderConstraints.mtls`, Authority validates the presented client certificate against stored bindings (`certificateBindings[]`), optional chain verification, and timing windows. Successful requests embed `cnf.x5t#S256` into the access token (and introspection output) so resource servers can enforce the certificate thumbprint.
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|   - `security.senderConstraints.mtls.enforceForAudiences` forces mTLS whenever the requested `aud`/`resource` (or the client's configured audiences) intersect the configured allow-list (default includes `signer`). Clients configured for different sender constraints are rejected early so operator policy remains consistent.
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|   - Certificate bindings now act as an allow-list: Authority verifies thumbprint, subject, issuer, serial number, and any declared SAN values against the presented certificate, with rotation grace windows applied to `notBefore/notAfter`. Operators can enforce subject regexes, SAN type allow-lists (`dns`, `uri`, `ip`), trusted certificate authorities, and rotation grace via `security.senderConstraints.mtls.*`.
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| 
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| Both modes persist additional metadata in `authority_tokens`: `senderConstraint` records the enforced policy, while `senderKeyThumbprint` stores the DPoP JWK thumbprint or mTLS certificate hash captured at issuance. Downstream services can rely on these fields (and the corresponding `cnf` claim) when auditing offline copies of the token store.
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| 
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| ### 7.2 Policy Engine clients & scopes
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| 
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| Policy Engine v2 introduces dedicated scopes and a service identity that materialises effective findings. Configure Authority as follows when provisioning policy clients:
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| 
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| | Client | Scopes | Notes |
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| | --- | --- | --- |
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| | `policy-engine` (service) | `policy:run`, `findings:read`, `effective:write` | Must include `properties.serviceIdentity: policy-engine` and a tenant. Authority rejects `effective:write` tokens without the marker or tenant. |
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| | `policy-cli` / automation | `policy:write`, `policy:submit`, `policy:run`, `findings:read` | Keep scopes minimal; only trusted automation should add `policy:approve`/`policy:activate`. |
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| | UI/editor sessions | `policy:read`, `policy:write`, `policy:simulate` (+ reviewer/approver scopes as appropriate) | Issue tenant-specific clients so audit and rate limits remain scoped. |
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| 
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| Sample YAML entry:
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| 
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| ```yaml
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|   - clientId: "policy-engine"
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|     displayName: "Policy Engine Service"
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|     grantTypes: [ "client_credentials" ]
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|     audiences: [ "api://policy-engine" ]
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|     scopes: [ "policy:run", "findings:read", "effective:write" ]
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|     tenant: "tenant-default"
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|     properties:
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|       serviceIdentity: "policy-engine"
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|     senderConstraint: "dpop"
 | ||
|     auth:
 | ||
|       type: "client_secret"
 | ||
|       secretFile: "../secrets/policy-engine.secret"
 | ||
| ```
 | ||
| 
 | ||
| Compliance checklist:
 | ||
| 
 | ||
| - [ ] `policy-engine` client includes `properties.serviceIdentity: policy-engine` and a tenant hint; logins missing either are rejected.
 | ||
| - [ ] Non-service clients omit `effective:write` and receive only the scopes required for their role (`policy:write`, `policy:submit`, `policy:approve`, `policy:activate`, etc.).
 | ||
| - [ ] Approval/activation workflows use identities distinct from authoring identities; tenants are provisioned per client to keep telemetry segregated.
 | ||
| - [ ] Operators document reviewer assignments and incident procedures alongside `/docs/security/policy-governance.md` and archive policy evidence bundles (`stella policy bundle export`) with each release.
 | ||
| 
 | ||
| ## 8. Offline & Sovereign Operation
 | ||
| - **No outbound dependencies:** Authority only contacts MongoDB and local plugins. Discovery and JWKS are cached by clients with offline tolerances (`AllowOfflineCacheFallback`, `OfflineCacheTolerance`). Operators should mirror these responses for air-gapped use.
 | ||
| - **Structured logging:** Every revocation export, signing rotation, bootstrap action, and token issuance emits structured logs with `traceId`, `client_id`, `subjectId`, and `network.remoteIp` where applicable. Mirror logs to your SIEM to retain audit trails without central connectivity.
 | ||
| - **Determinism:** Sorting rules in token and revocation exports guarantee byte-for-byte identical artefacts given the same datastore state. Hashes and signatures remain stable across machines.
 | ||
| 
 | ||
| ## 9. Operational Checklist
 | ||
| - [ ] Protect the bootstrap API key and disable bootstrap endpoints (`bootstrap.enabled: false`) once initial setup is complete.
 | ||
| - [ ] Schedule `stella auth revoke export` (or `/internal/revocations/export`) at the same cadence as Concelier exports so bundles remain in lockstep.
 | ||
| - [ ] Rotate signing keys before expiration; keep at least one retired key until all cached bundles/tokens signed with it have expired.
 | ||
| - [ ] Monitor `/health` and `/ready` plus rate-limiter metrics to detect plugin outages early.
 | ||
| - [ ] Ensure downstream services cache JWKS and revocation bundles within tolerances; stale caches risk accepting revoked tokens.
 | ||
| 
 | ||
| For plug-in specific requirements, refer to **[Authority Plug-in Developer Guide](dev/31_AUTHORITY_PLUGIN_DEVELOPER_GUIDE.md)**. For revocation bundle validation workflow, see **[Authority Revocation Bundle](security/revocation-bundle.md)**.
 |