bd8a13acb86e9ea30bfb1e5edce7516cc4860be7
2 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
 julien
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282a972346 |
feat(portal-bff): signed-assertion strategy + /.well-known/jwks.json (#138)
## Summary Second half of the **DownstreamApiClient + OBO** chantier per [ADR-0014](docs/decisions/0014-downstream-api-access-obo-pattern.md). Ships the **signed-assertion strategy** (non-Entra downstreams) and the **JWKS publishing endpoint** as testable primitives, completing the strategy layer the OBO PR (#137) started. The framework around them (DownstreamApiClientFactory, cockatiel, audience pre-check, error translation) still waits for the first concrete integration per the ADR's own "until then" clause. After this PR the BFF has, ready to plug into a future integration: - `OboStrategy` — Entra-protected downstreams (PR #137) - `SignedAssertionStrategy` — non-Entra downstreams (this PR) - `DownstreamTokenCache` — encrypted-at-rest OBO token cache (PR #137) - `GET /.well-known/jwks.json` — public key publication (this PR) ## What lands ### [`assertJwksConfig`](apps/portal-bff/src/config/check-jwks-config.ts) Boot validator for `BFF_JWKS_PRIVATE_KEY_PATH` + `BFF_JWKS_KID`. Reads the PEM file once at startup, refuses missing / unreadable / weak material (RSA < 2048, Ed25519, unknown key type), derives the JOSE algorithm (`RS256` / `ES256` / `ES384`) from the key shape, and validates the kid against `[A-Za-z0-9_-]{4,128}` so the value lives unescaped in JWT headers + JWKS payloads. ### [`BffSigningKey`](apps/portal-bff/src/downstream/bff-signing-key.ts) Singleton holding `{ config: JwksConfig, publicJwk: JWK }`. The `publicJwk` is derived from the **public half** of the key (via `jose.exportJWK` on a `createPublicKey`-derived `KeyObject`) so no private material can leak through. Single DI source for both consumers (strategy + JWKS controller) so a key rotation only changes one provider. ### [`SignedAssertionStrategy`](apps/portal-bff/src/downstream/strategies/signed-assertion.strategy.ts) Wraps `jose.SignJWT` with the ADR-0014 claim shape: ```json { "iss": "portal-bff", "sub": "<actor_id_hash>", "aud": "<downstream-name>", "audience": "workforce" | "customer", "claims": { /* curated subset */ }, "exp": <now + 60s>, "iat": <now>, "trace_id": "<W3C trace id>" } ``` - **60 s TTL** hard-coded — the ADR mandates it. - **No JWT cache** — at 60 s lifetime the savings would be negligible and a cache would let replayed assertions linger past their useful life. The signing operation itself is cheap (~hundreds of µs for RS256 with a 3 KB key). - **kid in the protected header** matches the JWKS so a downstream picks the right key during rotation. - Supports **RS256 / ES256 / ES384** transparently — picks the alg the validator derived at boot. ### [`JwksController`](apps/portal-bff/src/downstream/jwks.controller.ts) `GET /.well-known/jwks.json` returns `{ keys: [<single jwk>] }`. v1 publishes one key; the rotation chantier will add a second entry + window-based eviction so a downstream that cached the previous JWK keeps verifying during cut-over. [`main.ts`](apps/portal-bff/src/main.ts) excludes `/.well-known/*` from the global `/api` prefix so the route lands at the bare root per RFC 8615. No auth gate — the JWKS is the verification anchor; gating it would defeat the purpose. The CSRF middleware already exempts GET methods, so the route comes out clean. ## Required env update (mandatory at boot) Generate the key: ```bash mkdir -p apps/portal-bff/.secrets openssl genpkey -algorithm RSA -pkeyopt rsa_keygen_bits:3072 \ -out apps/portal-bff/.secrets/jwks.pem ``` Set in `apps/portal-bff/.env`: ```env BFF_JWKS_PRIVATE_KEY_PATH=apps/portal-bff/.secrets/jwks.pem BFF_JWKS_KID=bff-2026-05 ``` The repo's existing `*.pem` / `*.key` gitignore patterns cover `.secrets/`. ## Dependency - **`jose@^6`** added as a direct dep (was transitive via MSAL). Pinned at the workspace root since the BFF is the only consumer today and the package isn't part of the Angular bundle graph. - `jest.config.cts`: `jose` ships ESM-only, so its `node_modules` path is removed from `transformIgnorePatterns`. The pattern walks pnpm's deep `.pnpm/` layout — anything under `/node_modules/` whose path also contains `jose` somewhere gets transformed by ts-jest. ## Out of scope (deferred until the first concrete integration) Per ADR-0014's "until then" clause: - `DownstreamApiClientFactory` + per-service typed `DownstreamApiConfig`. - `cockatiel` resilience composition (timeout, retry, circuit breaker, bulkhead). - Audience pre-check at the call site (`audienceConstraint` → `authz.deny` audit). - Error translation tables per service. - OTel custom spans `downstream.<service>.<verb>.<path>`. - The framework code that actually calls `SignedAssertionStrategy.sign()` and attaches `X-User-Assertion` + the `ServiceCredential` auth header to an outbound HTTP request. - Key rotation (the JWKS lists one key for now; the rotation chantier adds the second entry + eviction policy). These land alongside the first concrete integration so the framework shape is validated against a real consumer, not speculative needs. ## Test plan - [x] `pnpm nx test portal-bff` — **358 specs pass** (was 334; +24: env validators 11, signing key 4, strategy 6, controller 3). - [x] `pnpm exec nx affected -t format:check lint test build --base=origin/main` — clean. - [x] Env validator: missing path, unreadable file, garbage PEM, RSA-1024 (weak), Ed25519 (unsupported), missing kid, illegal kid charset, kid too short. - [x] Signing key: RSA / EC P-256 / EC P-384 round-trip to public JWK with no private material (`d`, `p`, `q`, `dp`, `dq`, `qi` all absent from the published JWK). - [x] Strategy: claim shape matches ADR-0014, `exp - iat == 60`, audience mismatch rejected, signature mismatch rejected, EC P-256 signing path (ES256), per-call freshness. - [x] Controller: returns JWKS with the single public key, no private material leaks. - [ ] Manual smoke: generate a key locally + set the two env vars + `curl http://localhost:3000/.well-known/jwks.json` should return the JWKS shape with the chosen kid. ## Notes for the reviewer - The strategy uses `setProtectedHeader({ alg, kid })` — the kid in the protected header is the canonical way to tell a verifier "use the entry with this kid in the JWKS". Without it, a verifier holding two keys during rotation has to try both. - The `60 s` TTL is intentionally not env-overridable. ADR-0014 mandates it; making it tunable would create a tempting knob to widen the replay window for "performance". - `jose` was already in the tree transitively (likely via MSAL). Promoting it to a direct dep + pinning means a future hoist deduplication can't silently remove it without our review. ## What's next The chantier's strategy layer is complete. Open follow-ups on the roadmap: - **First concrete downstream integration** — when a real consumer arrives, the framework gets built around the two strategies (DownstreamApiClientFactory, cockatiel resilience, audience pre-check, error translation, OTel spans, audit events). Until then the strategies + cache + JWKS sit ready. - **Strategic security baseline ADR** — RSSI sign-off on ASVS / HDS / GDPR / NIS 2. Paused per [CLAUDE.md](CLAUDE.md) §"Repository status". - **portal-admin v1 modules** — CMS pages, menu management, user list. Each is its own self-contained chantier. --------- Co-authored-by: Julien Gautier <julien.gautier@apf.asso.fr> Reviewed-on: #138 |
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 Julien Gautier
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bea5e1954f |
chore: generate portal-shell and portal-bff apps per ADR-0004 / ADR-0005
Add the @nx/angular, @nx/nest, @nx/vite, @nx/eslint plugins, then generate the two apps. Adjust the empty-template tsconfig.base.json to be Angular-compatible (drop project references and customConditions that the empty-template defaults to but Angular doesn't support; keep the strict-TS extensions from ADR-0004). apps/portal-shell (Angular 21): - standalone APIs, routing, SCSS, esbuild - vitest-angular as unitTestRunner, playwright for e2e - strict mode - tags scope:portal-shell, type:app - app.config.ts wired with provideZonelessChangeDetection() per ADR-0004 (Angular 21 + Nx 22 generates without zone.js by default) apps/portal-bff (NestJS 11): - Express adapter (default per ADR-0005) - Jest as unitTestRunner - tags scope:portal-bff, type:app - main.ts wired with a global ValidationPipe configured whitelist + forbidNonWhitelisted + transform per ADR-0005 - Phase-2 security additions (helmet, CORS, sessions, CSRF, rate limit, auth guards, error filter) deferred to their respective ADRs - placeholder comment in main.ts Workspace dependencies: class-validator + class-transformer added (required by NestJS ValidationPipe at runtime). Nx-generated .gitignore additions (.angular, __screenshots__) merged into ours. .vscode/extensions.json and launch.json added by Nx are kept (do not override our existing settings.json). |