[AZ-529] [AZ-530] Cycle-2 documentation refresh

Refreshes _docs/02_document/ to reflect the cycle-2 auth-modernization + CMMC hardening landings (AZ-531..AZ-538). Authoritative source for the ripple set is ripple_log_cycle2.md. Covered: - architecture.md (section 1 rewritten, ADRs 6-9 added) - data_model.md (sessions, audit_events, user columns, migrations) - system-flows.md (F1 rewritten; F11-F17 added; F2/F7/F9 minor) - module-layout.md (cycle-2 sub-component table) - diagrams/flows/flow_login.md (dual-token + MFA) - components/{01_data_layer,03_auth_and_security,05_admin_api} - modules/ (12 new, 8 modified — full Argon2id/ES256/MFA/refresh /mission/session/audit/jwks rollup) - tests/{blackbox,security,traceability-matrix} Step 13 (Update Docs) output for cycle 2. Co-authored-by: Cursor <cursoragent@cursor.com>
2026-06-21 06:51:08 +00:00 · 2026-05-14 09:22:53 +03:00
parent c2c659ef62
commit a77b3f8a59
35 changed files with 3624 additions and 468 deletions
@@ -2,24 +2,36 @@

 ## 1. System Context

-**Problem being solved**: Azaion Suite requires a centralized admin API to manage users, assign roles, and securely distribute encrypted software resources (DLLs, AI models, installers) to authorized devices and SaaS users.
+**Problem being solved**: Azaion Suite requires a centralized admin API to manage users + roles, authenticate humans (with optional second factor), authenticate UAVs for offline missions, and broker token revocation across a fleet of verifier services.

 **System boundaries**:
- **Inside**: User management, authentication (JWT), role-based authorization, file-based resource storage (upload / list / clear).
- **Outside**: Client applications (admin web panel at admin.azaion.com, fTPM-secured Jetson edge devices), PostgreSQL database, server filesystem for resource storage.
+- **Inside**: user management, password hashing (Argon2id), authentication (ES256 JWT + opaque refresh tokens with rotation + reuse detection), TOTP MFA, mission-token issuance, session revocation + verifier-poll snapshot, account lockout + per-IP and per-account rate limiting, JWKS publication, role-based authorization, file-based resource storage (upload / list / clear), HSTS + HTTPS redirect.
+- **Outside**: admin web panel (`admin.azaion.com`), fTPM-secured Jetson edge devices (CompanionPC), verifier fleet (satellite-provider, gps-denied, ui — service-role identities), PostgreSQL, server filesystem.

-> **Note (AZ-197, 2026-05-13)**: hardware-fingerprint binding (`User.Hardware`, `CheckHardwareHash`, `PUT /users/hardware/set`, `POST /resources/check`, `HardwareIdMismatch`/`BadHardware` error codes) was removed. Edge devices now ship as fTPM-secured Jetsons; server/desktop access is SaaS-only. The `User.Hardware` DB column remains as a nullable tombstone (no migration in AZ-197).
-
-> **Note (cycle 2, 2026-05-14)**: the encrypted resource download (`POST /resources/get/{dataFolder?}`) and both installer endpoints (`GET /resources/get-installer`, `GET /resources/get-installer/stage`) were removed as obsolete. Their orphaned support code went with them: `ResourcesService.GetEncryptedResource` / `GetInstaller`, `Security.GetApiEncryptionKey` / `EncryptTo` / `DecryptTo`, the `GetResourceRequest` DTO (+ `WrongResourceName` error code 50, gap kept), and the `ResourcesConfig.SuiteInstallerFolder` / `SuiteStageInstallerFolder` properties + their env var rows in every config artifact. The `Azaion.Test` unit-test project became empty and was removed from the solution. Per-user file encryption is no longer part of the system; resource delivery is now upload + list + clear only. ADR-003 below is **retired** as a result.
+> **Note (AZ-197, cycle 1)**: hardware-fingerprint binding removed.
+>
+> **Note (cycle 2 early)**: encrypted resource download + installer endpoints removed; ADR-003 retired.
+>
+> **Note (cycle 2 — Auth Modernization, 2026-05-14, AZ-531..AZ-538)**: the entire authentication layer was rebuilt:
+> - **AZ-536** — Argon2id password hashing replaced SHA-384; lazy migration on login.
+> - **AZ-531** — opaque refresh tokens with server-side rotation, family-based reuse detection, sliding + absolute lifetimes (`SessionConfig`).
+> - **AZ-532** — symmetric HS256 → asymmetric ES256 with file-system key store + JWKS endpoint.
+> - **AZ-534** — TOTP MFA (enroll/confirm/disable, recovery codes, two-step login, `IDataProtector`-encrypted secret, `amr` claim).
+> - **AZ-535** — logout (single + all) + admin revoke + verifier-poll snapshot of revoked sessions; new `Service` role for verifier identities.
+> - **AZ-533** — long-lived no-refresh mission tokens for UAV ops, with auto-revoke on aircraft reconnect.
+> - **AZ-537** — DB-backed account lockout + per-account sliding-window rate limit + per-IP token-bucket via ASP.NET `RateLimiter`; `audit_events` table.
+> - **AZ-538** — CORS narrowed to single HTTPS origin, HSTS enabled (non-Development), HTTPS redirection (non-Development).
+> - New ADRs **ADR-006** through **ADR-009** below capture the per-decision context.

 **External systems**:

 | System | Integration Type | Direction | Purpose |
 |--------|-----------------|-----------|---------|
-| PostgreSQL | Database (linq2db) | Both | User data persistence |
-| Server filesystem | File I/O | Both | Resource file storage and retrieval |
-| Azaion Suite client | REST API | Inbound | Resource download, login |
-| Admin web panel (admin.azaion.com) | REST API | Inbound | User management, resource upload |
+| PostgreSQL | Database (linq2db) | Both | User + session + audit_events persistence |
+| Server filesystem | File I/O | Both | Resource files; ES256 PEM key store; DataProtection key store (when `DataProtection:KeysFolder` is set) |
+| Admin web panel (admin.azaion.com) | REST API | Inbound | User management, login, MFA, refresh, resource upload |
+| Verifier fleet (Service role) | REST API | Inbound | Polls `/sessions/revoked`, fetches `/.well-known/jwks.json` |
+| CompanionPC (Jetson) edge devices | REST API | Inbound | Login + refresh; mission-token consumer |

 ## 2. Technology Stack

@@ -30,11 +42,15 @@
 | Database | PostgreSQL | (server-side) | Open-source, robust relational DB |
 | ORM | linq2db | 5.4.1 | Lightweight, LINQ-native, no migrations overhead |
 | Cache | LazyCache (in-memory) | 2.4.0 | Simple async caching for user lookups |
-| Auth | JWT Bearer | 10.0.3 | Stateless token authentication |
+| Auth | JWT Bearer (ES256) | 10.0.3 | Stateless token auth; cycle 2 — switched from HS256 to ES256 with JWKS (AZ-532) |
+| Password hashing | Konscious.Security.Cryptography (Argon2id) | (cycle 2 add) | Replaces SHA-384 (AZ-536) |
+| MFA | OtpNet (TOTP) + QRCoder (PNG) | (cycle 2 add) | TOTP + recovery codes (AZ-534) |
+| Rate limiting | Microsoft.AspNetCore.RateLimiting | 10.0 | Per-IP sliding window (AZ-537) |
+| Data protection | Microsoft.AspNetCore.DataProtection | 10.0 | Encrypt MFA secret at rest (AZ-534) |
 | Validation | FluentValidation | 11.3.0 / 11.10.0 | Declarative request validation |
 | Logging | Serilog | 4.1.0 | Structured logging (console + file) |
 | API Docs | Swashbuckle (Swagger) | 10.1.4 | OpenAPI specification |
-| Serialization | Newtonsoft.Json | 13.0.1 | JSON for DB field mapping and responses |
+| Serialization | Newtonsoft.Json | 13.0.4 | JSON for DB field mapping and responses (bumped from 13.0.1 by audit D-1) |
 | Container | Docker | .NET 10.0 images | Multi-stage build, ARM64 support |
 | CI/CD | Woodpecker CI | — | Branch-based ARM64 builds |
 | Registry | docker.azaion.com | — | Private container registry |
@@ -56,7 +72,11 @@
 | Secrets | Environment variables (`ASPNETCORE_*`) | Environment variables |
 | Logging | Console + file | Console + rolling file (`logs/log.txt`) |
 | Swagger | Enabled | Disabled |
-| CORS | Same as prod | `admin.azaion.com` |
+| CORS | (same policy registered, allows `https://admin.azaion.com`) | `https://admin.azaion.com` only |
+| HSTS | **Disabled** (Development bypass) | **Enabled** (1 y, includeSubDomains, preload) |
+| HTTPS redirect | **Disabled** (Development bypass) | **Enabled** |
+| ES256 keys | `JwtConfig.KeysFolder` — at least one PEM, `ActiveKid` selects | Same; persistent volume mandatory |
+| DataProtection keys | Ephemeral OK (single-instance dev) | `DataProtection:KeysFolder` MUST be a persistent volume — otherwise MFA secrets are unrecoverable after restart |

 ## 4. Data Model Overview

@@ -64,21 +84,25 @@

 | Entity | Description | Owned By Component |
 |--------|-------------|--------------------|
-| User | System user with email (UNIQUE-indexed via `users_email_uidx`), password hash, role, config (legacy `Hardware` column tombstoned per AZ-197). Subset of users have `Role = CompanionPC` and are auto-provisioned via `POST /devices` (AZ-196), which delegates the insert to `UserService.RegisterUser` (post-security-audit consolidation, finding F-3). | 01 Data Layer |
-| UserConfig | JSON-serialized per-user configuration (queue offsets) | 01 Data Layer |
-| RoleEnum | Authorization role hierarchy (None → ApiAdmin); `ResourceUploader` retained as data only after the OTA endpoints were retired | 01 Data Layer |
-| DetectionClass *(AZ-513, cycle 1)* | Operator-managed detection-class catalogue (Name, ShortName, Color, MaxSizeM, PhotoMode?) backing the UI Detection Classes table | 01 Data Layer |
-| ExceptionEnum | Business error code catalog (HW-related codes 40/45 removed by AZ-197) | Common Helpers |
+| User | System user. Cycle 2 added `failed_login_count`, `lockout_until` (AZ-537) and `mfa_*` columns (AZ-534). `password_hash` is now Argon2id PHC; legacy SHA-384 base64 lazily upgraded on next login (AZ-536). | 01 Data Layer |
+| Session *(AZ-531+535+533+534)* | One row per refresh token (interactive) or per mission token. Carries `family_id` (rotation chain), `revoked_at`/`revoked_reason`/`revoked_by_user_id`, `class` ∈ {`interactive`, `mission`}, `aircraft_id`, `mfa_authenticated`. | 01 Data Layer |
+| AuditEvent *(AZ-537+534)* | Append-only `audit_events` row: login_failed/success/lockout, mfa_enroll/confirm/disable/login_success/login_failed/recovery_used. | 01 Data Layer |
+| UserConfig | JSON-serialized per-user configuration (queue offsets). | 01 Data Layer |
+| RoleEnum | Authorization role hierarchy. Cycle 2 added `Service = 60` for verifier identities (AZ-535). | 01 Data Layer |
+| DetectionClass | Operator-managed catalogue. Unchanged in cycle 2. | 01 Data Layer |
+| ExceptionEnum | Business error code catalog. Cycle 2 added codes 50–61 for the auth/MFA/refresh/mission/lockout paths. | Common Helpers |

-> **Removed in cycle 1 / post-cycle-1**: the `Resource` entity, the `resources` table, and the OTA delivery flow (AZ-183 — F10) were reverted after the security audit (finding F-1). The data model no longer carries an OTA-artifact entity.
-
-**Key relationships**:
- User → RoleEnum: each user has exactly one role
- User → UserConfig: optional 1:1 JSON field containing queue offsets
+**Key relationships** (cycle 2 additions):
+- User 1 — N Session (`sessions.user_id` FK, ON DELETE CASCADE)
+- User 1 — N Session (`sessions.aircraft_id` FK for mission rows, ON DELETE SET NULL)
+- User 1 — N Session (`sessions.revoked_by_user_id` FK, ON DELETE SET NULL)
+- Session 1 — N Session (`parent_session_id` rotation chain)

 **Data flow summary**:
- Client → API → UserService → PostgreSQL: user CRUD operations
- Client → API → ResourcesService → Filesystem: resource upload / list / clear (encrypted download + installer delivery were retired in cycle 2)
+- Client → API → UserService → PostgreSQL: user CRUD + Argon2id verify/hash + lazy migration
+- Client → API → RefreshTokenService / SessionService / MfaService / MissionTokenService → PostgreSQL `sessions` + `users` + `audit_events`
+- Verifier → API → SessionService → PostgreSQL `sessions` (revoked-since snapshot) + JwtSigningKeyProvider (JWKS)
+- Client → API → ResourcesService → Filesystem: resource upload / list / clear

 ## 5. Integration Points

@@ -86,11 +110,13 @@

 | From | To | Protocol | Pattern | Notes |
 |------|----|----------|---------|-------|
-| Admin API | User Management | Direct DI call | Request-Response | Scoped service injection |
-| Admin API | Auth & Security | Direct DI call | Request-Response | Scoped service injection |
-| Admin API | Resource Management | Direct DI call | Request-Response | Scoped service injection |
-| User Management | Data Layer | Direct DI call | Request-Response | Singleton DbFactory |
-| Auth & Security | User Management | Direct DI call | Request-Response | IUserService.GetByEmail |
+| Admin API | User Management | Direct DI call | Request-Response | Scoped |
+| Admin API | AuthService | Direct DI call | Request-Response | Scoped — also reads `IJwtSigningKeyProvider` (singleton) |
+| Admin API | RefreshTokenService / SessionService / MfaService / MissionTokenService / AuditLog | Direct DI call | Request-Response | Scoped |
+| Admin API | Resource Management | Direct DI call | Request-Response | Scoped |
+| User Management | AuditLog | Direct DI call | Request-Response | Failed/success/lockout audit + sliding-window count |
+| MfaService | IDataProtector | Direct DI call | Request-Response | Encrypt/decrypt mfa_secret |
+| All services | Data Layer | Direct DI call | Request-Response | Singleton DbFactory |

 ### External Integrations

@@ -104,29 +130,40 @@
 | Requirement | Target | Measurement | Priority |
 |------------|--------|-------------|----------|
 | Max upload size | 200 MB | Kestrel MaxRequestBodySize | High |
-| Password hashing | SHA-384 | Per-user | Medium |
+| Password hashing | Argon2id (parameters from `AuthConfig.PasswordHashing`) | Per-user, constant-time verify | High |
+| Access token lifetime | `JwtConfig.AccessTokenLifetimeMinutes` (15 default) | Per token | High |
+| Refresh token sliding lifetime | `SessionConfig.RefreshSlidingHours` | Per session row | High |
+| Refresh token absolute lifetime | `SessionConfig.RefreshAbsoluteHours` | Per family | High |
+| Mission token lifetime | `MissionSessionRequest.PlannedDurationH` (validation-bounded) | Per mission session | High |
+| Per-IP login rate | `AuthConfig.RateLimit.PerIpPermitLimit` per `PerIpWindowSeconds` | Sliding window | High |
+| Per-account login rate | `AuthConfig.RateLimit.PerAccountFailedThreshold` per `PerAccountWindowSeconds` | DB sliding window via `audit_events` | High |
+| Account lockout | `AuthConfig.Lockout.ConsecutiveFailureThreshold` failures → `LockoutSeconds` lockout | DB-backed | High |
+| HSTS | 1 y, includeSubDomains, preload (non-Development) | HTTP header | High |
+| HTTPS redirect | Enabled (non-Development) | Middleware | High |
 | Cache TTL | 4 hours | User entity cache | Low |

-> The "File encryption / AES-256-CBC" NFR was retired in cycle 2 along with the encrypted-download endpoint. See ADR-003.
-
 No explicit availability, latency, throughput, or recovery targets found in the codebase.

 ## 7. Security Architecture

-**Authentication**: JWT Bearer tokens (HMAC-SHA256 signed, validated for issuer/audience/lifetime/signing key).
+**Authentication**:
+- ES256 (ECDSA P-256) JWT bearer tokens (AZ-532). `ValidAlgorithms` pinned to `ES256` to prevent the HS256-with-public-key forgery class.
+- Opaque refresh tokens with server-side rotation + reuse detection (AZ-531). Stored as SHA-256 hashes; never re-presented.
+- TOTP MFA + recovery codes (AZ-534). Step-1 token is itself an ES256 JWT with a separate audience.
+- Mission tokens (AZ-533) — long-lived, no refresh, bound to `aircraft_id`, auto-revoked on aircraft reconnect.

 **Authorization**: Role-based (RBAC) via ASP.NET Core authorization policies:
- `apiAdminPolicy` — requires `ApiAdmin` role
+- `apiAdminPolicy` — requires `ApiAdmin`
+- `revocationReaderPolicy` — requires `Service` OR `ApiAdmin` (verifier fleet)
 - General `[Authorize]` — any authenticated user

-> The `apiUploaderPolicy` was added by AZ-183 and removed in the post-cycle-1 revert along with the OTA endpoints it guarded. `RoleEnum.ResourceUploader` remains as data only.
-
 **Data protection**:
- At rest: resource files are stored as plain bytes on the server filesystem (per-user AES-256-CBC encryption was retired in cycle 2 — see ADR-003).
- In transit: HTTPS (assumed, not enforced in code)
- Secrets management: Environment variables (`ASPNETCORE_*` prefix)
+- **At rest**: `mfa_secret` is encrypted via `IDataProtector` (purpose `Azaion.Mfa.Secret`). MFA recovery codes are individually Argon2id-hashed and single-use. Passwords are Argon2id PHC strings. ES256 PEM keys live in `JwtConfig.KeysFolder` — protect via filesystem permissions.
+- **In transit**: HSTS + HTTPS redirection in non-Development environments (AZ-538). CORS narrowed to `https://admin.azaion.com` only.
+- **Token revocation propagation**: `GET /sessions/revoked` provides a verifier-poll snapshot; verifiers are responsible for honoring it within their poll cadence (currently ~30s recommended).
+- **Secrets management**: Environment variables (`ASPNETCORE_*` prefix).

-**Audit logging**: No explicit audit trail. Serilog logs business exceptions (WARN) and general events (INFO).
+**Audit logging**: `audit_events` table records login_success/failed/lockout and mfa_enroll/confirm/disable/login_success/login_failed/recovery_used events with normalised email + caller IP. Drives the per-account rate limit and provides forensic evidence. Serilog continues to log business exceptions (WARN) and general events (INFO).

 ## 8. Key Architectural Decisions

@@ -174,3 +211,68 @@ The binding's only remaining effect was a real production failure mode (`Hardwar
 **Decision**: Use linq2db instead of Entity Framework Core.

 **Consequences**: No migration framework — schema managed via SQL scripts (`env/db/`). Lighter runtime footprint. Manual mapping configuration in `AzaionDbSchemaHolder`.
+
+### ADR-006: Asymmetric ES256 JWT signing with file-system key store + JWKS *(cycle 2 — AZ-532)*
+
+**Context**: Cycle-1 JWT signing was symmetric HS256 with the secret in environment configuration. The verifier fleet (satellite-provider, gps-denied, ui) needed to validate tokens without sharing the signing secret with every service. Sharing the HS256 secret would have made any verifier compromise also a token-forgery primitive.
+
+**Decision**: Switch to ES256 (ECDSA P-256). The Admin API holds the private key; verifiers fetch the public key set from `GET /.well-known/jwks.json`. Keys live as one PEM per kid in `JwtConfig.KeysFolder`. `JwtConfig.ActiveKid` selects the signer; ALL discovered keys are exposed in JWKS so existing tokens stay verifiable across rotations.
+
+**Alternatives rejected**:
+- **Continue HS256 + share secret**: rejected — secret-distribution + verifier-compromise blast radius.
+- **RS256**: equivalent security, larger keys, no operational benefit at our scale.
+- **External KMS / HSM**: deferred — adds operational complexity (KMS auth, latency on every signing op) without near-term benefit. The PEM-on-disk approach is reversible to KMS later.
+
+**Consequences**:
+- JwtBearer `ValidAlgorithms = [ES256]` is mandatory — without it, a token forged with `alg=HS256` using the public key as the HMAC secret would validate.
+- The PEM directory MUST be a persistent volume.
+- Key rotation is "drop a new PEM, set `ActiveKid`, restart" — the old kid keeps verifying tokens until physically removed.
+- Verifiers MUST cache the JWKS for at most 1 hour to pick up new kids quickly.
+
+### ADR-007: Refresh tokens as opaque rotating server-side rows (not JWT) *(cycle 2 — AZ-531)*
+
+**Context**: The dual-token model needs a refresh token. The two viable shapes are (a) signed self-describing JWT or (b) opaque server-stored value. Refresh tokens are long-lived; their threat model centres on theft + replay.
+
+**Decision**: Opaque random `Base64Url(32 bytes)` stored on the server as a SHA-256 hash. Each rotation marks the previous row as `revoked_reason='rotated'` and inserts a new row in the same `family_id`. Presenting an already-rotated token revokes the entire family with `reason='reuse_detected'`.
+
+**Alternatives rejected**:
+- **JWT refresh token**: server cannot revoke without a denylist (which negates the "stateless" advantage). No reuse-detection without ALSO server state.
+- **Sliding session ID alone (no rotation)**: theft is permanent until manual revocation.
+
+**Consequences**:
+- Every refresh hits Postgres (one indexed lookup + one update + one insert in a transaction). Acceptable at current load; if it becomes a bottleneck, the `sessions_refresh_hash_idx` UNIQUE INDEX is the obvious caching boundary.
+- Refresh-token theft is detectable on the next legitimate refresh.
+- The session row is also the `sid` claim in the access token — the same row drives logout (F12), JWKS-independent revocation snapshots (F15), and AMR persistence across rotations (`mfa_authenticated`).
+
+### ADR-008: TOTP MFA secrets encrypted via `IDataProtector` *(cycle 2 — AZ-534)*
+
+**Context**: MFA secrets are TOTP shared secrets — possession of the database alone (DBA access, backup leak) must NOT yield the ability to mint TOTP codes for users.
+
+**Decision**: Encrypt `mfa_secret` with ASP.NET `IDataProtector` (purpose string `Azaion.Mfa.Secret`) before persisting. The DataProtection key store is configured via `DataProtection:KeysFolder` and MUST be a persistent volume in production. Recovery codes are individually Argon2id-hashed and stored as a `jsonb` array; single-use is enforced by setting `used_at` transactionally with the rest of the login.
+
+**Alternatives rejected**:
+- **Plaintext**: explicit DB-leak escalation path.
+- **Application-managed AES via env-var key**: re-introduces the very key-distribution problem ADR-006 solved for JWT signing.
+- **External KMS for MFA secrets**: deferred for the same reason as ADR-006.
+
+**Consequences**:
+- Loss of the DataProtection key folder = users must re-enroll MFA (no recovery path). This MUST be backed up alongside DB backups.
+- DBA-only access does not yield MFA bypass.
+
+### ADR-009: Per-account lockout + DB-backed sliding-window rate limit alongside per-IP token bucket *(cycle 2 — AZ-537)*
+
+**Context**: ASP.NET `RateLimiter` is per-process and per-IP. CMMC AC.L2-3.1.8 requires per-account lockout that survives process restarts. Per-IP alone is insufficient (NAT'd attacker farm; bot rotates IPs). Per-account-only is insufficient (single IP can DoS many accounts at "just below threshold").
+
+**Decision**: Both layers, both required to pass:
+1. Per-IP — ASP.NET `RateLimiter` middleware with `SlidingWindowRateLimiter` on `/login` and `/login/mfa`. In-memory; resets on restart but recovers within seconds.
+2. Per-account — DB-backed sliding window via `audit_events` (count `login_failed` rows for the email within `PerAccountWindowSeconds`).
+3. Lockout — `users.failed_login_count` + `users.lockout_until`. After `ConsecutiveFailureThreshold` failures, `lockout_until = now + LockoutSeconds`. Subsequent logins throw `AccountLocked` with `RetryAfterSeconds` until the window passes.
+
+**Alternatives rejected**:
+- **Redis token bucket per account**: avoids DB load but adds a new infra dependency for a low-write workload. The DB sliding window has acceptable cost (`audit_events_event_type_email_idx`).
+- **Single combined rule**: harder to tune.
+
+**Consequences**:
+- `audit_events` will grow large (~14 GB/yr at projected fleet scale); operational follow-up to time-partition.
+- The `Retry-After` header is set both by the per-IP middleware (lease metadata) and by the `BusinessExceptionHandler` (from `BusinessException.RetryAfterSeconds`), so clients see consistent backoff hints regardless of which layer rejected.
+- All gating events go through `audit_events`, providing a single auditable history.
@@ -29,43 +29,66 @@

 ### Entities

-> **Cycle 1 (2026-05-13) note** — `DetectionClass` (AZ-513) entity was added. `Resource` (AZ-183) was added then removed in the same cycle (post-cycle-1 revert; security audit F-1 + the OTA delivery model itself was deemed obsolete). The `User.Hardware` column is left in place as a tombstone (nullable, unused) per AZ-197. A UNIQUE INDEX `users_email_uidx` was added on `users.email` (security audit F-3, `env/db/06_users_email_unique.sql`).
+> **Cycle 1 (2026-05-13) note** — `DetectionClass` (AZ-513) added; `Resource` (AZ-183) added then reverted same cycle. `User.Hardware` left as a tombstone (AZ-197). UNIQUE INDEX `users_email_uidx` added on `users.email` (security audit F-3, `env/db/06_users_email_unique.sql`).
 >
-> **Cycle 2 (2026-05-14) note** — `ResourcesConfig.SuiteInstallerFolder` and `SuiteStageInstallerFolder` were removed along with the installer endpoints (`GET /resources/get-installer[/stage]`); the POCO is now a single-property class (`ResourcesFolder`).
+> **Cycle 2 — early (2026-05-14)** — `ResourcesConfig.SuiteInstallerFolder` / `SuiteStageInstallerFolder` removed with the installer endpoints; `ResourcesConfig` is now `ResourcesFolder`-only.
+>
+> **Cycle 2 — Auth Modernization (2026-05-14)** — significant data-layer changes:
+> - **`User`** gained `FailedLoginCount`, `LockoutUntil` (AZ-537) and `MfaEnabled`, `MfaSecret` (DataProtection-encrypted), `MfaRecoveryCodes` (jsonb of Argon2id-hashed codes), `MfaEnrolledAt`, `MfaLastUsedWindow` (AZ-534). `PasswordHash` column unchanged in shape but now contains Argon2id PHC strings; legacy SHA-384 base64 values are accepted by `Security.VerifyPassword` and lazily upgraded on next login (AZ-536).
+> - **New table `public.sessions`** (AZ-531 / AZ-535) — refresh-token rotation + revocation, mapped via `Common/Entities/Session`.
+> - **New table `public.audit_events`** (AZ-537 + AZ-534) — append-only login + MFA event log, mapped via `Common/Entities/AuditEvent`.
+> - **New `RoleEnum.Service = 60`** (AZ-535) — verifier-fleet identity used by the `revocationReaderPolicy`.
+> - **New configs**: `AuthConfig` (rate limit + lockout + Argon2id parameters), `SessionConfig` (refresh sliding + absolute lifetimes). `JwtConfig` rebuilt around ES256 (`KeysFolder`, `ActiveKid`, `AccessTokenLifetimeMinutes`, `MfaStepTokenLifetimeMinutes`); the legacy `Secret` and `TokenLifetimeHours` fields are no longer read.
+> - **Migrations** added: `07_auth_lockout_and_audit.sql`, `08_sessions.sql`, `09_sessions_logout_and_mission.sql`, `10_users_mfa.sql`.

 ```
 User:
  Id: Guid (PK)
  Email: string (required)
-  PasswordHash: string (required)
-  Hardware: string? (optional — TOMBSTONED by AZ-197; nullable, unused; no application code reads or writes)
+  PasswordHash: string (required, Argon2id PHC; legacy SHA-384 base64 accepted on read, rehashed on next login — AZ-536)
+  Hardware: string? (TOMBSTONED — AZ-197)
  Role: RoleEnum (required)
-  CreatedAt: DateTime (required)
-  LastLogin: DateTime? (optional)
-  UserConfig: UserConfig? (optional, JSON-serialized)
-  IsEnabled: bool (required)
-
-UserConfig:
-  QueueOffsets: UserQueueOffsets? (optional)
-
-UserQueueOffsets:
-  AnnotationsOffset: ulong
-  AnnotationsConfirmOffset: ulong
-  AnnotationsCommandsOffset: ulong
-
-DetectionClass (AZ-513):
-  Id: int (PK, DB-assigned identity)
-  Name, ShortName, Color: string
-  MaxSizeM: double
-  PhotoMode: string?
  CreatedAt: DateTime
+  LastLogin: DateTime?
+  UserConfig: UserConfig?
+  IsEnabled: bool
+  FailedLoginCount: int (AZ-537 — reset on successful login)
+  LockoutUntil: DateTime? (AZ-537 — UTC; "now < LockoutUntil" → AccountLocked)
+  MfaEnabled: bool (AZ-534)
+  MfaSecret: string? (AZ-534 — IDataProtector-encrypted base32 TOTP secret)
+  MfaRecoveryCodes: List<string>? (AZ-534 — jsonb of Argon2id-hashed single-use codes)
+  MfaEnrolledAt: DateTime?
+  MfaLastUsedWindow: long? (AZ-534 — anti-replay; last consumed TOTP step)

-// Resource entity — REMOVED post-cycle-1 (AZ-183 reverted). The `resources`
-// table no longer exists; see env/db/ for the current migration set.
+Session (AZ-531 / AZ-535):
+  Id: Guid (PK — used as the JWT `sid` claim)
+  UserId: Guid (FK to users)
+  Class: string ("interactive" | "mission")
+  RefreshTokenHash: byte[]? (SHA-256 of opaque refresh; null for mission sessions)
+  RotatedFromTokenId: Guid? (chain pointer for reuse detection)
+  IssuedAt: DateTime
+  ExpiresAt: DateTime (sliding for interactive, absolute for mission)
+  RevokedAt: DateTime?
+  RevokedReason: string? (one of SessionRevokedReasons)
+  RevokedByUserId: Guid?
+  Ip: string?
+  UserAgent: string?
+  MfaAuthenticated: bool (AZ-534 — pinned at issue, inherited by rotations)
+  AircraftId: Guid? (mission-only)
+  MissionId: string? (mission-only)

-RoleEnum: None=0, Operator=10, Validator=20, CompanionPC=30, Admin=40, ResourceUploader=50, ApiAdmin=1000
-// ResourceUploader is now data-only — no endpoint policy references it
-// after AZ-183 was reverted.
+AuditEvent (AZ-537 + AZ-534):
+  Id: long (PK identity)
+  EventType: string (one of AuditEventTypes — login_failed/success/lockout, mfa_*)
+  Email: string (lowercase normalised)
+  Ip: string?
+  OccurredAt: DateTime (UTC)
+
+DetectionClass (AZ-513): unchanged
+
+RoleEnum: None=0, Operator=10, Validator=20, CompanionPC=30, Admin=40, ResourceUploader=50, Service=60 (AZ-535), ApiAdmin=1000
+// ResourceUploader is data-only since AZ-183 revert.
+// Service is the verifier-fleet identity used by revocationReaderPolicy.
 ```

 ### Configuration POCOs
@@ -75,16 +98,33 @@ ConnectionStrings:
  AzaionDb: string — read-only connection string
  AzaionDbAdmin: string — admin (read/write) connection string

-JwtConfig:
+JwtConfig (AZ-532):
  Issuer: string
  Audience: string
-  Secret: string
-  TokenLifetimeHours: double
+  KeysFolder: string                — directory containing one PEM per kid
+  ActiveKid: string                 — selects the signing key
+  AccessTokenLifetimeMinutes: int   — default 15
+  MfaStepTokenLifetimeMinutes: int  — default 5 (AZ-534)
+  # Secret + TokenLifetimeHours: no longer read; kept only for back-compat deserialisation
+
+SessionConfig (AZ-531):
+  RefreshSlidingHours: int      — sliding window per rotate
+  RefreshAbsoluteHours: int     — hard cap (no rotation past this)
+  RevokedSnapshotMinutes: int   — verifier-poll grace window for /sessions/revoked
+
+AuthConfig (AZ-536 + AZ-537):
+  PasswordHashing: { TimeCost, MemoryCostKiB, Parallelism } — Argon2id parameters
+  RateLimit:
+    PerIpPermitLimit: int
+    PerIpWindowSeconds: int
+    PerAccountWindowSeconds: int
+    PerAccountFailedThreshold: int
+  Lockout:
+    ConsecutiveFailureThreshold: int
+    LockoutSeconds: int

 ResourcesConfig:
  ResourcesFolder: string
-  # SuiteInstallerFolder / SuiteStageInstallerFolder removed in cycle 2 with the installer endpoints.
-  # EncryptionMasterKey was added by AZ-183 and removed in the post-cycle-1 revert.
 ```

 ## 3. External API Specification
@@ -97,25 +137,34 @@ N/A — internal component.

 | Query | Frequency | Hot Path | Index Needed |
 |-------|-----------|----------|--------------|
-| `SELECT * FROM users WHERE email = ?` | High | Yes | Yes — UNIQUE INDEX `users_email_uidx` on `email` (security audit F-3, `env/db/06_users_email_unique.sql`) |
+| `SELECT * FROM users WHERE email = ?` | High | Yes | Yes — UNIQUE INDEX `users_email_uidx` on `email` |
 | `SELECT * FROM users` with optional filters | Medium | No | No |
 | `UPDATE users SET ... WHERE email = ?` | Medium | No | No |
-| `INSERT INTO users` | Low | No | No (UNIQUE INDEX above also enforces single-row-per-email atomically) |
+| `INSERT INTO users` | Low | No | UNIQUE INDEX above |
 | `DELETE FROM users WHERE email = ?` | Low | No | No |
+| `SELECT * FROM sessions WHERE refresh_token_hash = ?` (AZ-531) | High | Yes | Yes — UNIQUE INDEX on `refresh_token_hash` (`08_sessions.sql`) |
+| `UPDATE sessions SET revoked_at..., revoked_reason... WHERE id = ?` (AZ-535) | Medium | No | PK |
+| `UPDATE sessions SET revoked_... WHERE user_id = ? AND revoked_at IS NULL` (AZ-535 logout/all) | Low | No | INDEX on `(user_id, revoked_at)` |
+| `UPDATE sessions SET revoked_... WHERE aircraft_id = ? AND class='mission' AND revoked_at IS NULL` (AZ-533) | Low | No | INDEX on `(aircraft_id, class, revoked_at)` |
+| `SELECT ... FROM sessions WHERE revoked_at >= ? AND expires_at > now()` (AZ-535 verifier poll) | High | Yes | INDEX on `revoked_at` |
+| `SELECT count(*) FROM audit_events WHERE event_type='login_failed' AND email=? AND occurred_at >= ?` (AZ-537) | High | Yes | INDEX on `(email, event_type, occurred_at)` |
+| `INSERT INTO audit_events (...)` (AZ-537 / AZ-534) | High | Yes | n/a |

 ### Caching Strategy

 | Data | Cache Type | TTL | Invalidation |
 |------|-----------|-----|-------------|
-| User by email | In-memory (LazyCache) | 4 hours | On `UpdateQueueOffsets` (post-AZ-197 — hardware paths gone) |
+| User by email | In-memory (LazyCache) | 4 hours | On `UpdateQueueOffsets`, on lazy-rehash (AZ-536), on MFA enroll/confirm/disable (AZ-534), on user enable/disable, on lockout state changes (AZ-537) |

-> The `Resources.Latest.{arch}.{stage}` cache key (added by AZ-183) was removed in the post-cycle-1 revert.
+> Refresh tokens, sessions, and audit events are NOT cached — they are read directly from Postgres on every request. The verifier-poll snapshot (`/sessions/revoked`) is the only "edge" cache and lives in the verifier process, not in this component.

 ### Storage Estimates

 | Table | Est. Row Count (1yr) | Row Size | Total Size | Growth Rate |
 |-------|---------------------|----------|------------|-------------|
-| `users` | 100–1000 web users + 2000–10000 CompanionPC device users (AZ-196 grows this) | ~500 bytes | ~5 MB | Medium (device fleet) |
+| `users` | 100–1000 web users + 2000–10000 CompanionPC device users | ~700 bytes (post-MFA columns) | ~7 MB | Medium |
+| `sessions` (AZ-531) | 30 d retention (`RefreshAbsoluteHours`) × N active sessions per user × pruning job | ~400 bytes | ~50 MB ceiling | High during active fleet ops; bounded by retention |
+| `audit_events` (AZ-537) | ~50 events/user/day × ~5000 users × 365 d | ~150 bytes | ~14 GB/yr | High — partition or archive after 90 d (operational follow-up) |
 | `detection_classes` (AZ-513) | 10–200 | ~250 bytes | ~50 KB | Low |

 ### Data Management
@@ -182,12 +231,15 @@ N/A — internal component.

 ## Modules Covered
 - `Common/Configs/ConnectionStrings`
- `Common/Configs/JwtConfig`
+- `Common/Configs/JwtConfig` *(AZ-532 — ES256 + session config)*
+- `Common/Configs/AuthConfig` *(new in cycle 2 — AZ-536 + AZ-537)*
 - `Common/Configs/ResourcesConfig`
- `Common/Entities/User`
- `Common/Entities/RoleEnum`
+- `Common/Entities/User` *(extended in cycle 2 — AZ-537 + AZ-534)*
+- `Common/Entities/RoleEnum` *(extended in cycle 2 — AZ-535 added `Service`)*
+- `Common/Entities/Session` *(new in cycle 2 — AZ-531 + AZ-535)*
+- `Common/Entities/AuditEvent` *(new in cycle 2 — AZ-537)*
 - `Common/Entities/DetectionClass` *(added cycle 1, AZ-513)*
- `Common/Database/AzaionDb` (now also holds the `DetectionClasses` table; the `Resources` ITable added by AZ-183 was removed in the post-cycle-1 revert)
- `Common/Database/AzaionDbSchemaHolder`
+- `Common/Database/AzaionDb` (`Sessions` and `AuditEvents` ITables added in cycle 2)
+- `Common/Database/AzaionDbSchemaHolder` (Session + AuditEvent mappings, jsonb for `MfaRecoveryCodes`)
 - `Common/Database/DbFactory`
 - `Services/Cache`
@@ -1,90 +1,181 @@
 # Authentication & Security

-> **Cycle 1 (2026-05-13) note** — AZ-197 simplified `GetApiEncryptionKey` to `(email, password)` and removed `GetHWHash` outright. The hardware-binding threat model that motivated those primitives is no longer in scope (fTPM-anchored Jetsons + browser SaaS).
+> **Cycle 1 (2026-05-13) note** — AZ-197 simplified `GetApiEncryptionKey` to `(email, password)` and removed `GetHWHash` outright. The hardware-binding threat model is no longer in scope.
 >
-> **Cycle 2 (2026-05-14) note** — `GetApiEncryptionKey`, `EncryptTo`, and `DecryptTo` were all removed along with the encrypted-download endpoint. `Security` is now a one-method utility (`ToHash`) that backs SHA-384 password hashing.
+> **Cycle 2 — early (2026-05-14, batches 01-04)** — `GetApiEncryptionKey`, `EncryptTo`, and `DecryptTo` were removed along with the encrypted-download endpoint. `Security` was briefly a one-method utility (`ToHash`) wrapping SHA-384.
+>
+> **Cycle 2 — Auth Modernization (2026-05-14, AZ-531..AZ-538)** — this component was rebuilt from a single-token issuer + SHA-384 hasher into the full session/refresh/MFA/audit/mission stack described below. Old single-token, symmetric-HS256, SHA-384 paths are gone.

 ## 1. High-Level Overview

-**Purpose**: JWT token creation/validation and password hashing (`Security.ToHash`).
+**Purpose**: end-to-end authentication, authorization, session management, second factor (TOTP), token signing/verification, mission credentials, audit, and request-time abuse protection (rate limiting / lockout).

-**Architectural Pattern**: Service + static utility — `AuthService` is a DI-managed service for JWT operations; `Security` is a static class with a single SHA-384 helper.
+**Architectural Pattern**: a cluster of focused DI-registered services backed by Postgres tables, fronted by Admin API endpoints. Token signing is asymmetric (ES256) with file-system key storage and JWKS publication. Refresh tokens use server-side rotation with reuse detection. MFA secrets are encrypted at rest via ASP.NET `IDataProtector`.

-**Upstream dependencies**: Data Layer (JwtConfig, IUserService for GetByEmail), ASP.NET Core (IHttpContextAccessor).
+**Upstream dependencies**:
+- Data Layer (`AzaionDb`, `JwtConfig`, `SessionConfig`, `AuthConfig`, `IUserService.GetByEmail`)
+- ASP.NET Core (`IHttpContextAccessor`, `IDataProtectionProvider`, `RateLimiter` middleware)
+- File system (`JwtConfig.KeysFolder` for ES256 keys; one PEM per kid)

-**Downstream consumers**: Admin API (token creation on login, current user resolution), User Management (password hashing for both web users and provisioned devices).
+**Downstream consumers**:
+- Admin API endpoints (`/login`, `/login/mfa`, `/refresh`, `/logout`, `/logout/all`, `/users/me/mfa/*`, `/sessions/{sid}`, `/aircraft/{id}/sessions`, `/sessions/revoked`, `/missions/sessions`, `/.well-known/jwks.json`)
+- All authorized requests (JWT bearer middleware verifies via `IJwtSigningKeyProvider` and Verifier services consult the revoked-sessions snapshot)
+- User Management (Argon2id hashing for register/update; lazy migration on login)

 ## 2. Internal Interfaces

-### Interface: IAuthService
+### Service: `IAuthService`

-| Method | Input | Output | Async | Error Types |
-|--------|-------|--------|-------|-------------|
-| `GetCurrentUser` | (none — reads from HttpContext) | `User?` | Yes | None |
-| `CreateToken` | `User` | `string` (JWT) | No | None |
+| Method | Input | Output | Async | Notes |
+|--------|-------|--------|-------|-------|
+| `GetCurrentUser` | (HttpContext) | `User?` | Yes | Reads `ClaimTypes.Name` (email) and looks up via `IUserService.GetByEmail` |
+| `CreateToken` | `User`, `Guid sessionId`, `Guid jti`, `IEnumerable<string>? amr` | `AccessToken` (record: `Jwt`, `ExpiresAt`) | No | ES256 signed; lifetime from `JwtConfig.AccessTokenLifetimeMinutes`. Stamps `sub` (`NameIdentifier`), `email` (`Name`), `role`, `sid`, `jti`, and one `amr` claim per value (defaults to `["pwd"]`). |

-### Static: Security
+### Service: `IRefreshTokenService` *(AZ-531)*
+
+| Method | Input | Output | Notes |
+|--------|-------|--------|-------|
+| `IssueForNewLogin` | `Guid userId`, `bool mfaAuthenticated`, `CancellationToken` | `(string OpaqueToken, Session Session)` | Creates a new session family (the returned `Session.Id` is the `sid` claim) + initial refresh token. `MfaAuthenticated` is pinned on the session so refresh rotations inherit AMR strength. |
+| `Rotate` | `string opaqueToken`, `CancellationToken` | `(string OpaqueToken, Session Session)` | Validates → marks old as rotated → inserts new row in same family. Presenting an already-rotated token revokes the entire family. |
+
+### Service: `ISessionService` *(AZ-535)*
+
+| Method | Input | Output |
+|--------|-------|--------|
+| `RevokeBySid` | `Guid sessionId`, `Guid? byUserId`, `string reason`, `CancellationToken` | `Task<bool>` (true = was already revoked = no-op) |
+| `RevokeAllForUser` | `Guid userId`, `Guid? byUserId`, `string reason`, `CancellationToken` | `Task<int>` (rows revoked) |
+| `RevokeMissionsForAircraft` | `Guid aircraftId`, `CancellationToken` | `Task<int>` (called from `MissionTokenService.Issue` and from any successful aircraft re-login) |
+| `GetRevokedSince` | `DateTime since`, `CancellationToken` | `Task<IReadOnlyList<RevokedSession>>` (sid, exp, revokedAt, reason) |
+
+### Service: `IMfaService` *(AZ-534)*
+
+| Method | Input | Output |
+|--------|-------|--------|
+| `Enroll` | `Guid userId`, `string password`, `CancellationToken` | `Task<MfaEnrollResponse>` (otpauth URL, base32 secret, QR PNG bytes — DataProtection-encrypted secret persisted) |
+| `Confirm` | `Guid userId`, `string code`, `CancellationToken` | `Task` (sets `MfaEnabled=true`, generates and stores hashed recovery codes) |
+| `Disable` | `Guid userId`, `string password`, `string code`, `CancellationToken` | `Task` |
+| `IssueMfaStepToken` | `Guid userId` | `string` (short-lived JWT with `mfa_pending`, audience `mfa-step`, signed by active ES256 key) |
+| `ValidateMfaStepToken` | `string token` | `Guid userId` |
+| `VerifyForLogin` | `Guid userId`, `string code`, `CancellationToken` | `Task<string[]>` — returns the AMR array (`["pwd","mfa"]` or with `"recovery"` appended); throws `InvalidMfaCode` on failure |
+
+### Service: `IMissionTokenService` *(AZ-533)*
+
+| Method | Input | Output | Notes |
+|--------|-------|--------|-------|
+| `Issue` | `Guid pilotUserId`, `MissionSessionRequest`, `CancellationToken` | `Task<MissionSessionResponse>` | Validates aircraft is `CompanionPC`; auto-revokes prior mission sessions for the aircraft; inserts session row with `Class = "mission"` BEFORE signing so `sid` is bound; planned duration = absolute lifetime (no refresh). |
+
+### Service: `IJwtSigningKeyProvider` *(AZ-532)*
+
+| Member | Output | Notes |
+|--------|--------|-------|
+| `Active` | `JwtSigningKey` (`Kid`, `EcdsaSecurityKey SecurityKey`, `ECDsa Ecdsa`) | The signing key. Eager — constructed once at app start so missing/malformed keys fail-fast. |
+| `All` | `IReadOnlyList<JwtSigningKey>` | Drives `/.well-known/jwks.json` and `IssuerSigningKeyResolver`. All discovered keys are exposed; only `Active` signs. |
+
+### Service: `IAuditLog` *(AZ-537 + AZ-534)*
+
+| Method | Purpose |
+|--------|---------|
+| `RecordLoginSuccess(email)` / `RecordLoginFailed(email)` / `RecordLoginLockout(email)` | Persists `audit_events` rows with normalised email + caller IP. |
+| `RecordMfaEnroll/Confirm/Disable/LoginSuccess/LoginFailed/RecoveryUsed(email)` | One per MFA lifecycle event. |
+| `CountRecentFailedLogins(email, windowSeconds)` | Backs the per-account sliding-window check in `UserService.ValidateUser`. |
+
+### Static: `Security` *(AZ-536 — replaces SHA-384)*

 | Method | Input | Output | Description |
 |--------|-------|--------|-------------|
-| `ToHash` | `string` | `string` (Base64) | SHA-384 hash |
+| `HashPassword` | `string` | `string` (PHC) | Argon2id, parameters from `AuthConfig.PasswordHashing` |
+| `VerifyPassword` | `string presented`, `string stored` | `VerifyResult` (`Ok`, `NeedsRehash`) | Constant-time; recognizes legacy SHA-384 base64 strings and returns `Ok=true, NeedsRehash=true` so `UserService` can lazy-upgrade |

 **Removed**:
- `GetHWHash(string hardware)` — removed by AZ-197 (cycle 1).
- `GetApiEncryptionKey(string email, string password)` — removed in cycle 2 (no remaining callers after `POST /resources/get/{dataFolder?}` was deleted).
- `EncryptTo` / `DecryptTo` extension methods — removed in cycle 2 (no remaining callers; the only consumer was `ResourcesService.GetEncryptedResource`, also deleted).
+- `ToHash(string)` — removed by AZ-536. All callers now use `HashPassword` / `VerifyPassword`.
+- `GetHWHash`, `GetApiEncryptionKey`, `EncryptTo`, `DecryptTo` — removed earlier in cycle 2.

 ## 3. External API Specification

-N/A — exposed through Admin API.
+Exposed via Admin API (component 05). Cycle 2 added:
+
+- `POST /login` — now returns either `LoginResponse` (access + refresh + sid) or `MfaRequiredResponse` (mfa_token only when MFA is enabled). Per-IP sliding-window rate limit applied.
+- `POST /login/mfa` — completes MFA login (anonymous + per-IP rate limit; the step-1 token is the proof of mid-flow) → `LoginResponse`
+- `POST /token/refresh` — rotates refresh token + new access token (anonymous; the refresh token IS the proof)
+- `POST /logout` — revokes the caller's current `sid` (read from the access-token claim). Idempotent.
+- `POST /logout/all` — revokes every session for the caller's user
+- `POST /users/me/mfa/enroll` / `confirm` / `disable`
+- `POST /sessions/{sid:guid}/revoke` *(ApiAdmin)*
+- `GET /sessions/revoked?since=...` *(verifier role / ApiAdmin via `revocationReaderPolicy`)*
+- `POST /sessions/mission` *(authenticated; pilot's interactive token)* → mission `LoginResponse`-shaped reply
+- `GET /.well-known/jwks.json` — anonymous; serves all loaded ES256 public keys (active + retiring); cached 1h.

 ## 4. Data Access Patterns

-No direct database access. `AuthService.GetCurrentUser` delegates to `IUserService.GetByEmail`.
+| Service | Tables touched | Pattern |
+|---------|----------------|---------|
+| `RefreshTokenService` | `public.sessions` | Insert on issue / rotate; update `RevokedAt`+`RevokedReason` on rotate / reuse-detected; index lookup by `RefreshTokenHash` |
+| `SessionService` | `public.sessions` | Update by `Sid`; bulk update by `UserId`; range read for revoked-since snapshot |
+| `MfaService` | `public.users` | Update MFA columns (`MfaEnabled`, `MfaSecret`, `MfaRecoveryCodes`, `MfaEnrolledAt`, `MfaLastUsedWindow`) |
+| `MissionTokenService` | `public.sessions`, `public.users` | Insert mission session row; lookup aircraft user |
+| `AuditLog` | `public.audit_events`, `public.users` | Insert events; update `FailedLoginCount` / `LockoutUntil` on the user |
+| `AuthService` / `UserService` | `public.users` | Reads for current-user resolution and password verify; updates on lazy rehash |
+
+All tables are LinqToDB-mapped via `AzaionDbShemaHolder`; recovery codes use `jsonb`.

 ## 5. Implementation Details

-**Algorithmic Complexity**: SHA-384 hashing is O(n) where n is input length; in practice it operates on short password strings only.
+**Argon2id parameters** (cycle 2 default): time=3, memory=64 MiB, parallelism=2 — overridable via `AuthConfig.PasswordHashing`. Output is a PHC-format string self-describing all parameters; verification re-derives them from the stored value.

-**State Management**: `AuthService` is stateless (reads claims from HTTP context per request). `Security` is purely static.
+**ES256 keys**: one PEM file per kid in `JwtConfig.KeysFolder`. `ActiveKid` selects the signer; all PEMs with valid `P-256` curves are exposed via JWKS. Rotation procedure: drop a new PEM, set `ActiveKid` to it, restart. Old keys remain in JWKS until physically removed (by ops) so already-issued tokens stay verifiable.

-**Key Dependencies**:
+**Refresh token format**: opaque random `Base64Url(32 bytes)`. Server stores SHA-256 hash + family id (`Sid`) + `RotatedFromTokenId` to support reuse detection. Sliding window per `SessionConfig.RefreshSlidingHours`; absolute cap per `SessionConfig.RefreshAbsoluteHours`.

-| Library | Version | Purpose |
-|---------|---------|---------|
-| System.IdentityModel.Tokens.Jwt | 7.1.2 | JWT token generation |
-| Microsoft.AspNetCore.Authentication.JwtBearer | 10.0.3 | JWT middleware integration |
+**Reuse detection**: presenting an already-rotated refresh token revokes the entire family (`Sid`) with reason `RefreshReuseDetected`. The next-snapshot poll picks this up.

-**Error Handling Strategy**:
- JWT token creation does not throw (malformed config would cause runtime errors at middleware level).
- `GetCurrentUser` returns null if claims are missing or user not found.
+**MFA**:
+- Secret: 20 random bytes → base32; URL `otpauth://totp/Azaion:{email}?secret=...&issuer=Azaion`.
+- QR: PNG generated with `QRCoder` and returned as bytes (only on enroll).
+- Recovery codes: 10 codes, each `Argon2id`-hashed before storage. Single-use; checked on `VerifyForLoginAsync` after TOTP fails.
+- Step-1 token: short-lived JWT (`mfa_pending = true`, audience `mfa-step`) signed by the active ES256 key. Lifetime `JwtConfig.MfaStepTokenLifetimeMinutes`.
+- Replay defense: persisted `MfaLastUsedWindow` blocks reuse of the same TOTP window within the 30s step.
+
+**Rate limiting / lockout** (AZ-537):
+- Per-IP token-bucket via ASP.NET Core `RateLimiter` on `/login`, `/login/mfa`, `/refresh`.
+- Per-account sliding window via `IAuditLog.CountRecentFailedLoginsAsync`; threshold + window from `AuthConfig.RateLimit`.
+- Lockout via `LockoutOptions`: N consecutive failures within window → `LockoutUntil` set; subsequent logins throw `AccountLocked` with `RetryAfterSeconds`.
+
+**HSTS / HTTPS / CORS** (AZ-538):
+- HSTS enabled in non-Development with the standard 1y `includeSubDomains` policy.
+- HTTPS redirection in non-Development.
+- CORS narrowed to the configured admin origins; credentials allowed only for those origins.

 ## 6. Extensions and Helpers

-None — `Security` itself is a utility consumed by other components.
+- `Program.cs` helpers: `ParseSidClaim`, `ParseUserIdClaim` (both throw `InvalidRefreshToken` on malformed/missing claims so handlers don't need to repeat the check).
+- `BusinessExceptionHandler` adds the `Retry-After` header for `AccountLocked` / `LoginRateLimited`.

 ## 7. Caveats & Edge Cases

-**Known limitations**:
- Password hashing uses SHA-384 without per-user salt or key stretching. Not resistant to rainbow table attacks. (Unchanged by cycles 1 and 2.)
- `GetCurrentUserEmail` assumes `ClaimTypes.Name` is always present; accessing a missing key would throw `KeyNotFoundException`.
-
-**Removed in cycle 1**: hardware fingerprint hashing was a known weakness (static salt, no rotation); deleting it via AZ-197 also removed that attack surface.
-
-**Removed in cycle 2**: per-user file encryption (`GetApiEncryptionKey` + `EncryptTo` + `DecryptTo`). The hardcoded encryption-key salt and the in-memory `MemoryStream` round-trip are no longer attack / performance surfaces in this codebase.
+- **Asymmetric key roll-forward only**: revoking a kid means deleting its PEM. There is no per-kid revocation list separate from the file system. Operators must coordinate kid retirement with refresh-token expiry.
+- **Verifier polling cadence**: `GET /sessions/revoked?since=` returns the snapshot since a timestamp. Verifiers must clock-skew-tolerate by stepping `since` back ~30s. Snapshot rows are pruned only after both `expiry + grace` window has passed.
+- **MFA recovery codes are single-use**: there is no `regenerate` endpoint in cycle 2. A user who burns all 10 codes and loses their authenticator must contact an admin to disable MFA via `/users/me/mfa/disable` (re-uses password + TOTP, so admin is currently NOT able to disable on behalf of the user — flagged as a follow-up).
+- **Mission tokens have no refresh**: `planned_duration_h` is the hard cap; expiry is absolute. Aircraft must re-request via the admin path on re-connect.
+- **Lazy password rehash leak window**: a successful login with a SHA-384 stored hash returns `Ok=true, NeedsRehash=true` and `UserService` re-hashes via Argon2id within the same request. If that update fails (DB error), the legacy hash stays — surfaced via logs but not blocking.

 ## 8. Dependency Graph

-**Must be implemented after**: Data Layer (for JwtConfig, IUserService).
+**Must be implemented after**: Data Layer (configs + DB tables `users`, `sessions`, `audit_events`).

-**Can be implemented in parallel with**: User Management (shared dependency on Data Layer).
-
-**Blocks**: Admin API. (Resource Management no longer depends on this component after cycle 2 removed `EncryptTo` / `DecryptTo`.)
+**Blocks**: Admin API (every authenticated endpoint), Verifier components (consume `GET /sessions/revoked` and JWKS).

 ## 9. Logging Strategy

-No explicit logging in AuthService or Security.
+- All MFA failures, lockouts, refresh-reuse events, and admin revocations log at `Warning`+ via `IAuditLog` and structured logger.
+- Successful logins log at `Information`.
+- Argon2id verification failures log only the audit row (no plaintext, no hash).

 ## Modules Covered
 - `Services/AuthService`
 - `Services/Security`
+- `Services/RefreshTokenService`
+- `Services/SessionService`
+- `Services/MfaService`
+- `Services/MissionTokenService`
+- `Services/JwtSigningKeyProvider`
+- `Services/AuditLog`
@@ -2,133 +2,201 @@

 ## 1. High-Level Overview

-**Purpose**: HTTP API entry point — configures DI, middleware pipeline, authentication, authorization, CORS, Swagger, and defines all REST endpoints using ASP.NET Core Minimal API.
+**Purpose**: HTTP API entry point — configures DI, middleware pipeline, authentication, authorization, CORS, HSTS, HTTPS redirection, rate limiting, Swagger, DataProtection, and defines all REST endpoints using ASP.NET Core Minimal API.

-**Architectural Pattern**: Composition root + Minimal API endpoints — top-level statements configure the application and map HTTP routes to service methods.
+**Architectural Pattern**: Composition root + Minimal API endpoints — top-level statements configure the application and map HTTP routes to service methods. A static `IssueDualTokens` helper centralises the access+refresh issuance pattern shared by `/login` (no MFA) and `/login/mfa` (with MFA), and a tiny `ParseSidClaim` / `ParseUserIdClaim` pair extracts session/user identity from the request principal.

-**Upstream dependencies**: User Management (IUserService), Authentication & Security (IAuthService, Security), Resource Management (IResourcesService), Data Layer (IDbFactory, ICache, configs).
+**Upstream dependencies**: Authentication & Security (AuthService, RefreshTokenService, SessionService, MissionTokenService, MfaService, JwtSigningKeyProvider, AuditLog, Security), User Management (IUserService), Resource Management (IResourcesService), Detection Classes (IDetectionClassService), Data Layer (IDbFactory, ICache, all configs).

-**Downstream consumers**: None (top-level entry point, consumed by HTTP clients).
+**Downstream consumers**: HTTP clients (admin web UI, verifier services, CompanionPC).

 ## 2. Internal Interfaces

 ### BusinessExceptionHandler

-| Method | Input | Output | Async | Error Types |
-|--------|-------|--------|-------|-------------|
-| `TryHandleAsync` | `HttpContext, Exception, CancellationToken` | `bool` | Yes | None |
+| Method | Input | Output | Async |
+|--------|-------|--------|-------|
+| `TryHandleAsync` | `HttpContext`, `Exception`, `CancellationToken` | `bool` | Yes |

-Converts `BusinessException` to HTTP 409 JSON response: `{ ErrorCode: int, Message: string }`.
+Cycle 2 (AZ-537 / AZ-531 / AZ-533 / AZ-534 / AZ-535) — the handler now maps `BusinessException` → an exception-specific HTTP status code via a `MapStatusCode` switch, preserves the legacy `409 Conflict` default, and stamps a `Retry-After` response header when `RetryAfterSeconds` is set. It also handles `BadHttpRequestException` → `400 Bad Request` with `{ ErrorCode: 0, Message }` so malformed payloads have a consistent shape with business errors.
+
+| `ExceptionEnum` | HTTP status |
+|-----------------|-------------|
+| `AccountLocked` | `423 Locked` |
+| `LoginRateLimited` | `429 Too Many Requests` |
+| `InvalidRefreshToken` / `InvalidMfaCode` / `InvalidMfaToken` | `401 Unauthorized` |
+| `SessionNotFound` | `404 Not Found` |
+| `InvalidMissionRequest` / `AircraftNotFound` | `400 Bad Request` |
+| `MfaAlreadyEnabled` / `MfaNotEnrolling` / `MfaNotEnabled` | `409 Conflict` |
+| any other | `409 Conflict` (legacy default) |
+
+### Static helpers in `Program.cs`
+
+- `IssueDualTokens(user, authService, refreshTokens, sessionService, amr, ct)` — issues a refresh token + an access token, also auto-revokes any open mission sessions if the just-authenticated user is a `CompanionPC` (AZ-533 AC-4).
+- `ParseSidClaim(ClaimsPrincipal)` / `ParseUserIdClaim(ClaimsPrincipal)` — read `sid` / `nameid` claims; throw `BusinessException(InvalidRefreshToken)` (→ 401) on missing/malformed.

 ## 3. External API Specification

-> **Cycle 1 (2026-05-13) note** — endpoints below reflect the post-cycle-1 surface (AZ-513 Detection Classes CRUD, AZ-196 device auto-provisioning, AZ-197 hardware-binding removal). AZ-183 (OTA) shipped in cycle 1 but was reverted later the same day after the security audit (finding F-1) — the OTA delivery model itself was deemed obsolete. For per-endpoint cycle origins see `modules/admin_api_program.md`.
+> **Cycle 2 (2026-05-14) — auth modernization**: `/login` is now multi-shape (MFA branch); `/login/mfa`, `/token/refresh`, `/logout`, `/logout/all`, `/sessions/*`, `/users/me/mfa/*`, `/.well-known/jwks.json` are all new. The legacy "single JWT" response is preserved as a `Token` getter on `LoginResponse` for compatibility with old clients (= same value as `AccessToken`).
+
+### Authentication & Sessions
+
+| Endpoint | Method | Auth | Cycle | Description |
+|----------|--------|------|-------|-------------|
+| `/login` | POST | Anonymous | AZ-531/534/537 | Validates credentials. Returns `LoginResponse` (access + refresh + sid) OR `MfaRequiredResponse` (`mfa_required: true`, short-lived `mfa_token`). Per-IP rate limited. |
+| `/login/mfa` | POST | Anonymous | AZ-534 | Validates the step-1 `mfa_token` + the user's TOTP / recovery code. Returns `LoginResponse`. Per-IP rate limited. |
+| `/token/refresh` | POST | Anonymous | AZ-531 | Rotates a refresh token. Reuse of a rotated token revokes the entire session family. |
+| `/logout` | POST | Authenticated | AZ-535 | Revokes the caller's current `sid` (idempotent). |
+| `/logout/all` | POST | Authenticated | AZ-535 | Revokes every active session for the caller's user. |
+| `/sessions/{sid:guid}/revoke` | POST | ApiAdmin | AZ-535 | Admin-revoke by session id. |
+| `/sessions/revoked` | GET | revocationReader (Service or ApiAdmin) | AZ-535 | Verifier-poll snapshot of revoked sessions still within their TTL. `since` is clamped to a 12 h floor to prevent table scans. |
+| `/sessions/mission` | POST | Authenticated | AZ-533 | Pilot issues a long-lived no-refresh mission token bound to one aircraft + one mission. |
+| `/.well-known/jwks.json` | GET | Anonymous | AZ-532 | All loaded ES256 public keys (active + retiring). `Cache-Control: public, max-age=3600`. |
+
+### MFA

-### Authentication
 | Endpoint | Method | Auth | Description |
 |----------|--------|------|-------------|
-| `/login` | POST | Anonymous | Validates credentials, returns JWT |
+| `/users/me/mfa/enroll` | POST | Authenticated | Starts TOTP enrollment, returns secret + otpauth URL + PNG QR. |
+| `/users/me/mfa/confirm` | POST | Authenticated | Confirms with a TOTP code. Returns `{ mfaEnabled: true }`. |
+| `/users/me/mfa/disable` | POST | Authenticated | Requires password + TOTP. Returns `{ mfaEnabled: false }`. |

 ### User Management
+
 | Endpoint | Method | Auth | Description |
 |----------|--------|------|-------------|
-| `/users` | POST | ApiAdmin | Creates a new user |
-| `/devices` | POST | ApiAdmin | **AZ-196**: provisions a CompanionPC device user (returns serial + email + plaintext password once) |
-| `/users/current` | GET | Authenticated | Returns current user |
-| `/users` | GET | ApiAdmin | Lists users (optional email/role filters) |
-| `/users/queue-offsets/set` | PUT | Authenticated | Updates queue offsets |
-| `/users/{email}/set-role/{role}` | PUT | ApiAdmin | Changes user role |
-| `/users/{email}/enable` | PUT | ApiAdmin | Enables user |
-| `/users/{email}/disable` | PUT | ApiAdmin | Disables user |
-| `/users/{email}` | DELETE | ApiAdmin | Removes user |
-
-**Removed by AZ-197**: `PUT /users/hardware/set` (Hardware-binding feature deleted)
+| `/users` | POST | ApiAdmin | Creates a new user (Argon2id-hashed password, AZ-536). |
+| `/devices` | POST | ApiAdmin | Provisions a CompanionPC device user (returns serial + email + plaintext password once). |
+| `/users/current` | GET | Authenticated | Returns current user. |
+| `/users` | GET | ApiAdmin | Lists users (optional email/role filters). |
+| `/users/queue-offsets/set` | PUT | Authenticated | Updates queue offsets. |
+| `/users/{email}/set-role/{role}` | PUT | ApiAdmin | Changes user role. |
+| `/users/{email}/enable` | PUT | ApiAdmin | Enables user. |
+| `/users/{email}/disable` | PUT | ApiAdmin | Disables user (revokes all active sessions for that user via `SessionService`). |
+| `/users/{email}` | DELETE | ApiAdmin | Removes user. |

 ### Resource Management
+
 | Endpoint | Method | Auth | Description |
 |----------|--------|------|-------------|
-| `/resources/{dataFolder?}` | POST | Authenticated | Uploads a file (up to 200 MB) |
-| `/resources/list/{dataFolder?}` | GET | Authenticated | Lists files |
-| `/resources/clear/{dataFolder?}` | POST | ApiAdmin | Clears folder |
-
-**Removed by AZ-197**: `POST /resources/check` (was the hardware-binding side-effect probe).
-**Removed in post-cycle-1 revert**: `POST /get-update` and `POST /resources/publish` (AZ-183 reverted — security audit F-1; OTA delivery model itself obsolete).
-**Removed in cycle 2 (2026-05-14)**: `POST /resources/get/{dataFolder?}`, `GET /resources/get-installer`, `GET /resources/get-installer/stage` — all obsolete; the encrypted-download support stack (`Security.GetApiEncryptionKey` / `EncryptTo` / `DecryptTo`, `ResourcesService.GetEncryptedResource` / `GetInstaller`, `GetResourceRequest`, `WrongResourceName = 50`, `ResourcesConfig.SuiteInstallerFolder` / `SuiteStageInstallerFolder`) was removed with them. ADR-003 retired.
+| `/resources/{dataFolder?}` | POST | Authenticated | Uploads a file (up to 200 MB). |
+| `/resources/list/{dataFolder?}` | GET | Authenticated | Lists files. |
+| `/resources/clear/{dataFolder?}` | POST | ApiAdmin | Clears folder. |

 ### Detection Classes
+
 | Endpoint | Method | Auth | Description |
 |----------|--------|------|-------------|
-| `/classes` | POST | ApiAdmin | **AZ-513**: creates a detection class |
-| `/classes/{id:int}` | PATCH | ApiAdmin | **AZ-513**: partial-merge update of a detection class |
-| `/classes/{id:int}` | DELETE | ApiAdmin | **AZ-513**: deletes a detection class |
+| `/classes` | POST | ApiAdmin | Creates a detection class. |
+| `/classes/{id:int}` | PATCH | ApiAdmin | Partial-merge update. |
+| `/classes/{id:int}` | DELETE | ApiAdmin | Deletes a detection class. |
+
+### Health
+
+| Endpoint | Method | Auth | Description |
+|----------|--------|------|-------------|
+| `/health/live` | GET | Anonymous (excluded from Swagger) | Process liveness; never touches DB. |
+| `/health/ready` | GET | Anonymous (excluded from Swagger) | Pings both DB connections with a 2 s timeout; 503 on failure. |

 ### Authorization Policies
- **apiAdminPolicy**: requires `ApiAdmin` role (used on most admin endpoints)

-> The `apiUploaderPolicy` was added by AZ-183 and removed in the post-cycle-1 revert along with the OTA endpoints it guarded. `RoleEnum.ResourceUploader` remains as data only.
+| Policy | Roles | Notes |
+|--------|-------|-------|
+| `apiAdminPolicy` | `ApiAdmin` | The "admin endpoints" policy. |
+| `revocationReaderPolicy` | `Service`, `ApiAdmin` | AZ-535 — verifier services authenticate as `Service`-role identities and are the only callers (besides admin) allowed to read `/sessions/revoked`. |

-### CORS
- Allowed origins: `https://admin.azaion.com`, `http://admin.azaion.com`
- All methods/headers, credentials allowed
+> The `apiUploaderPolicy` from AZ-183 was removed in the post-cycle-1 revert. `RoleEnum.ResourceUploader` remains as data only.
+
+### CORS, HSTS, HTTPS (AZ-538)
+
+- **CORS** — single origin `https://admin.azaion.com`, `AllowAnyMethod` + `AllowAnyHeader` + `AllowCredentials`. The legacy `http://` origin combined with credentials would have permitted credentialed cleartext traffic; cycle 2 removed it.
+- **HSTS** — non-Development only: 1 y `MaxAge`, `IncludeSubDomains`, `Preload`.
+- **HTTPS redirection** — non-Development only. Development skips both so `dotnet watch` on plain HTTP keeps working.
+
+### Rate limiting (AZ-537)
+
+- **Per-IP** — ASP.NET Core `RateLimiter` middleware with a `SlidingWindowRateLimiter`. Policy `login-per-ip` is attached to `/login` and `/login/mfa`. Permit limit + window seconds come from `AuthConfig.RateLimit`. Rejection sets `429` and stamps `Retry-After`.
+- **Per-account** — DB-backed sliding-window check in `UserService.ValidateUser` via `IAuditLog.CountRecentFailedLogins`. Survives process restarts.
+- **Per-account lockout** — `LockoutOptions` in `AuthConfig`. N consecutive failures → `LockoutUntil`; subsequent logins throw `AccountLocked` with `RetryAfterSeconds`.

 ## 4. Data Access Patterns

-No direct data access — delegates to service components.
+No direct data access — delegates to service components. The composition root also fail-fast checks on missing connection strings (`AzaionDb`, `AzaionDbAdmin`) and missing `JwtConfig` (`Issuer` + `Audience` required).

 ## 5. Implementation Details

 **State Management**: Stateless — ASP.NET Core request pipeline.

+**DI registrations added in cycle 2**:
+- `IJwtSigningKeyProvider` (singleton, eager-built before DI so it's the same instance JwtBearer's `IssuerSigningKeyResolver` uses)
+- `IRefreshTokenService`, `ISessionService`, `IMissionTokenService`, `IMfaService` (scoped)
+- `IAuditLog` (scoped)
+- `IDataProtectionProvider` via `AddDataProtection().SetApplicationName("Azaion.AdminApi")` — production deployments MUST set `DataProtection:KeysFolder` to a persistent volume so encrypted MFA secrets survive restarts.
+
+**Middleware pipeline (cycle 2 order)**:
+1. `UseSwagger`/`UseSwaggerUI` (Development only)
+2. `UseHsts` + `UseHttpsRedirection` (non-Development only)
+3. `UseCors("AdminCorsPolicy")`
+4. `UseAuthentication`
+5. `UseAuthorization`
+6. `UseRateLimiter`
+7. `UseRewriter` (root → `/swagger`)
+8. Endpoint mappings
+9. `UseExceptionHandler` (registered last so the `BusinessExceptionHandler` exception-handler component runs)
+
+**JWT Bearer config**:
+- `ValidAlgorithms = [SecurityAlgorithms.EcdsaSha256]` — pinned to ES256 so a token forged with `alg=HS256` using the public key as the HMAC secret cannot pass validation (AZ-532 AC-5).
+- `IssuerSigningKeyResolver` consults the same `IJwtSigningKeyProvider` instance the rest of the app uses; if the token has a `kid` it's matched, otherwise all loaded keys are returned.
+- `ValidateIssuer`, `ValidateAudience`, `ValidateLifetime`, `ValidateIssuerSigningKey` all true.
+
 **Key Dependencies**:

-| Library | Version | Purpose |
-|---------|---------|---------|
-| Swashbuckle.AspNetCore | 10.1.4 | Swagger/OpenAPI documentation |
-| FluentValidation.AspNetCore | 11.3.0 | Request validation pipeline |
-| Serilog | 4.1.0 | Structured logging |
-| Serilog.Sinks.Console | 6.0.0 | Console log output |
-| Serilog.Sinks.File | 6.0.0 | Rolling file log output |
+| Library | Purpose |
+|---------|---------|
+| Microsoft.AspNetCore.Authentication.JwtBearer | JWT bearer middleware |
+| Microsoft.AspNetCore.RateLimiting | Per-IP sliding window |
+| Microsoft.AspNetCore.DataProtection | Encrypt MFA secrets at rest |
+| Microsoft.AspNetCore.Rewrite | `/` → `/swagger` redirect |
+| Swashbuckle.AspNetCore | Swagger/OpenAPI |
+| FluentValidation.AspNetCore | Request validation pipeline |
+| Serilog | Structured logging (Console + rolling file) |

 **Error Handling Strategy**:
- `BusinessException` → `BusinessExceptionHandler` → HTTP 409 with JSON body.
- `UnauthorizedAccessException` → thrown in resource endpoints when current user is null.
- `FileNotFoundException` → thrown when installer not found.
- FluentValidation errors → automatic 400 Bad Request via middleware.
- Unhandled exceptions → default ASP.NET Core exception handling.
+- `BusinessException` → `BusinessExceptionHandler` → per-enum status code (see table above) + optional `Retry-After`.
+- `BadHttpRequestException` → `400 Bad Request` with `{ ErrorCode: 0, Message }`.
+- FluentValidation errors → 400 via `Results.ValidationProblem`.
+- Unhandled → default ASP.NET Core handling.

 ## 6. Extensions and Helpers

-None.
+- `IssueDualTokens` static helper (Program.cs)
+- `ParseSidClaim` / `ParseUserIdClaim` static helpers (Program.cs)

 ## 7. Caveats & Edge Cases

-**Known limitations**:
- All endpoints are defined in a single `Program.cs` file — no route grouping or controller separation.
- Swagger UI only available in Development environment.
- CORS origins are hardcoded (not configurable).
- Antiforgery disabled for resource upload endpoint.
- Root URL (`/`) redirects to `/swagger`.
-
-**Performance bottlenecks**:
- Kestrel max request body: 200 MB — allows large file uploads but could be a memory concern.
+- All endpoints are still defined in a single `Program.cs` file — cycle 2 added significantly more endpoints; consider splitting into endpoint groups in a future cycle.
+- Swagger UI only available in Development.
+- CORS origins are hardcoded — moving to config is a follow-up.
+- `BusinessExceptionHandler` lives under namespace `Azaion.Common` despite the file path `Azaion.AdminApi/`. Documented as historical accident; do not "fix" without coordinated rename.
+- Antiforgery disabled on resource upload.
+- Kestrel max request body 200 MB.
+- The eager `JwtSigningKeyProvider` construction means a missing or malformed PEM crashes the app at startup. This is intentional — it's safer than serving requests with no signing key.

 ## 8. Dependency Graph

 **Must be implemented after**: All other components (composition root).

-**Can be implemented in parallel with**: Nothing — depends on all services.
-
 **Blocks**: Nothing.

 ## 9. Logging Strategy

-| Log Level | When | Example |
-|-----------|------|---------|
-| WARN | Business exception caught | `BusinessExceptionHandler` logs the exception |
-| INFO | Serilog minimum level | General application events |
+| Log Level | When | Notes |
+|-----------|------|-------|
+| `Warning` | Business exception caught by `BusinessExceptionHandler` | Includes the full exception |
+| `Warning` | `BadHttpRequestException` caught | |
+| `Information` | Default for everything else | Serilog minimum level |

 **Log format**: Serilog structured logging with context enrichment.
-
 **Log storage**: Console + rolling file (`logs/log.txt`, daily rotation).

 ## Modules Covered
@@ -1,24 +1,72 @@
 # Azaion Admin API — Data Model

+> **Cycle 2 (2026-05-14) — Auth Modernization**: this doc is rewritten to reflect Postgres state after migrations `07`, `08`, `09`, `10`. Three new tables/columns clusters were added: account-lockout + audit (AZ-537), refresh-token sessions + revocation + mission tokens (AZ-531/535/533), TOTP MFA (AZ-534).
+
 ## Entity-Relationship Diagram

 ```mermaid
 erDiagram
    USERS {
        uuid id PK
-        varchar email "unique, not null"
-        varchar password_hash "not null"
-        text hardware "nullable"
-        varchar hardware_hash "nullable"
-        varchar role "not null (text enum)"
-        varchar user_config "nullable (JSON)"
-        timestamp created_at "not null, default now()"
-        timestamp last_login "nullable"
-        bool is_enabled "not null, default true"
+        varchar email "unique"
+        varchar password_hash "Argon2id PHC; legacy SHA-384 base64 lazily upgraded"
+        text hardware "tombstoned (AZ-197)"
+        varchar role
+        varchar user_config "JSON"
+        timestamp created_at
+        timestamp last_login
+        bool is_enabled
+        int failed_login_count "AZ-537"
+        timestamp lockout_until "AZ-537"
+        bool mfa_enabled "AZ-534"
+        text mfa_secret "AZ-534, IDataProtector-encrypted"
+        jsonb mfa_recovery_codes "AZ-534"
+        timestamp mfa_enrolled_at "AZ-534"
+        bigint mfa_last_used_window "AZ-534"
    }
-```

-The system has a single table (`users`). There are no foreign key relationships.
+    SESSIONS {
+        uuid id PK
+        uuid user_id FK
+        text refresh_hash "nullable for missions"
+        uuid family_id "AZ-531 reuse-detection key"
+        timestamp issued_at
+        timestamp last_used_at
+        timestamp expires_at
+        timestamp revoked_at
+        varchar revoked_reason
+        uuid parent_session_id FK
+        timestamp family_started_at
+        uuid revoked_by_user_id FK "AZ-535"
+        varchar class "AZ-533: interactive | mission"
+        uuid aircraft_id FK "AZ-533"
+        bool mfa_authenticated "AZ-534"
+    }
+
+    AUDIT_EVENTS {
+        bigserial id PK
+        varchar event_type
+        timestamp occurred_at
+        varchar email
+        varchar ip
+        text metadata
+    }
+
+    DETECTION_CLASSES {
+        int id PK
+        varchar name
+        varchar short_name
+        varchar color
+        double max_size_m
+        varchar photo_mode
+        timestamp created_at
+    }
+
+    USERS ||--o{ SESSIONS : owns
+    USERS ||--o{ SESSIONS : "revoked_by (AZ-535)"
+    USERS ||--o{ SESSIONS : "aircraft (AZ-533)"
+    SESSIONS ||--o{ SESSIONS : "rotated_from (AZ-531)"
+```

 ## Table: `users`

@@ -26,56 +74,147 @@ The system has a single table (`users`). There are no foreign key relationships.

 | Column | Type | Nullable | Default | Description |
 |--------|------|----------|---------|-------------|
-| `id` | `uuid` | No | (application-generated) | Primary key, `Guid.NewGuid()` |
-| `email` | `varchar(160)` | No | — | Unique user identifier |
-| `password_hash` | `varchar(255)` | No | — | SHA-384 hash, Base64-encoded |
-| `hardware` | `text` | Yes | null | Raw hardware fingerprint string |
-| `hardware_hash` | `varchar(120)` | Yes | null | Defined in DDL but not used by application code |
-| `role` | `varchar(20)` | No | — | Text representation of `RoleEnum` |
-| `user_config` | `varchar(512)` | Yes | null | JSON-serialized `UserConfig` object |
-| `created_at` | `timestamp` | No | `now()` | Account creation time |
-| `last_login` | `timestamp` | Yes | null | Last hardware check / resource access time |
-| `is_enabled` | `bool` | No | `true` | Account active flag |
+| `id` | `uuid` | No | (application-generated) | Primary key |
+| `email` | `varchar(160)` | No | — | Unique (UNIQUE INDEX `users_email_uidx`, security audit F-3) |
+| `password_hash` | `varchar(255)` | No | — | **AZ-536**: Argon2id PHC string. Legacy SHA-384 base64 strings are accepted on verify and lazily re-hashed to Argon2id on next successful login. |
+| `hardware` | `text` | Yes | null | TOMBSTONED (AZ-197) |
+| `role` | `varchar(20)` | No | — | Text representation of `RoleEnum` (now includes `Service` — AZ-535) |
+| `user_config` | `varchar(512)` | Yes | null | JSON-serialized `UserConfig` |
+| `created_at` | `timestamp` | No | `now()` | |
+| `last_login` | `timestamp` | Yes | null | Updated on successful login |
+| `is_enabled` | `bool` | No | `true` | Setting to `false` triggers `SessionService.RevokeAllForUser` |
+| `failed_login_count` | `int` | No | `0` | **AZ-537**: incremented on failed login; reset on success or lockout release |
+| `lockout_until` | `timestamp` | Yes | null | **AZ-537**: UTC; `now() < lockout_until` → `BusinessException(AccountLocked)` with `Retry-After` |
+| `mfa_enabled` | `boolean` | No | `false` | **AZ-534** |
+| `mfa_secret` | `text` | Yes | null | **AZ-534**: base32 TOTP secret, IDataProtector-encrypted (purpose `Azaion.Mfa.Secret`), then base64 |
+| `mfa_recovery_codes` | `jsonb` | Yes | null | **AZ-534**: array of `{ hash: <argon2id>, used_at: <ts|null> }`; single-use enforced by setting `used_at` |
+| `mfa_enrolled_at` | `timestamp` | Yes | null | **AZ-534** |
+| `mfa_last_used_window` | `bigint` | Yes | null | **AZ-534**: last accepted RFC 6238 step counter; anti-replay |

-### ORM Mapping (linq2db)
+### Indexes

-Column names are auto-converted from PascalCase to snake_case via `AzaionDbSchemaHolder`:
- `User.PasswordHash` → `password_hash`
- `User.CreatedAt` → `created_at`
+| Index | Type | Columns |
+|-------|------|---------|
+| `users_pkey` | PK | `id` |
+| `users_email_uidx` | UNIQUE | `email` |

-Special mappings:
- `Role`: stored as text, converted to/from `RoleEnum` via `Enum.Parse`
- `UserConfig`: stored as nullable JSON string, serialized/deserialized via `Newtonsoft.Json`
+## Table: `sessions` *(AZ-531 + AZ-535 + AZ-533 + AZ-534)*
+
+One row per issued refresh token. Mission tokens are also rows here (`class='mission'`, `refresh_hash` null).
+
+### Columns
+
+| Column | Type | Nullable | Default | Description |
+|--------|------|----------|---------|-------------|
+| `id` | `uuid` | No | (application) | PK; used as the JWT `sid` claim |
+| `user_id` | `uuid` | No | — | FK → `users.id` ON DELETE CASCADE |
+| `refresh_hash` | `text` | Yes | — | SHA-256 of opaque refresh token. Required for `class='interactive'`; null for `class='mission'` (AZ-533) |
+| `family_id` | `uuid` | No | — | **AZ-531**: shared by every rotation in the same login session; reuse detection revokes by `family_id` |
+| `issued_at` | `timestamp` | No | `now()` | |
+| `last_used_at` | `timestamp` | No | `now()` | Updated on rotate |
+| `expires_at` | `timestamp` | No | — | Sliding for interactive (`SessionConfig.RefreshSlidingHours`), absolute for mission (`planned_duration_h`) |
+| `revoked_at` | `timestamp` | Yes | null | Set on rotate (`rotated`), reuse detection (`reuse_detected`), logout (`logged_out`), logout/all (`logged_out_all`), admin revoke (`admin_revoked`), aircraft reconnect (`aircraft_reconnected`), user disable, refresh expiry sweep |
+| `revoked_reason` | `varchar(64)` | Yes | null | One of `SessionRevokedReasons` constants |
+| `parent_session_id` | `uuid` | Yes | null | FK → `sessions.id`; rotation chain pointer |
+| `family_started_at` | `timestamp` | No | `now()` | Hard cap is `family_started_at + RefreshAbsoluteHours` |
+| `revoked_by_user_id` | `uuid` | Yes | null | **AZ-535**: who revoked (admin id, system, or self for logout) |
+| `class` | `varchar(32)` | No | `'interactive'` | **AZ-533**: `interactive` or `mission` |
+| `aircraft_id` | `uuid` | Yes | null | **AZ-533**: FK → `users.id`; only set for `class='mission'` |
+| `mfa_authenticated` | `boolean` | No | `false` | **AZ-534**: pinned at issue; refresh rotations inherit it |
+
+### Indexes
+
+| Index | Type | Columns | Notes |
+|-------|------|---------|-------|
+| `sessions_pkey` | PK | `id` | |
+| `sessions_refresh_hash_idx` | UNIQUE | `refresh_hash` | O(1) lookup on rotate; nulls allowed (mission rows) |
+| `sessions_family_active_idx` | partial | `family_id` WHERE `revoked_at IS NULL` | Reuse-detection family revoke; logout-all |
+| `sessions_aircraft_active_idx` | partial | `(aircraft_id, class)` WHERE `revoked_at IS NULL AND aircraft_id IS NOT NULL` | **AZ-533** auto-revoke-on-reconnect |
+| `sessions_revoked_at_idx` | partial | `revoked_at` WHERE `revoked_at IS NOT NULL` | **AZ-535** verifier-poll snapshot |
+
+### Lifecycle
+
+- **Issue (interactive)**: `RefreshTokenService.IssueForNewLogin` inserts a row with new `id` and `family_id`; `mfa_authenticated` reflects the login path.
+- **Rotate**: `RefreshTokenService.Rotate` updates the existing row's `revoked_at`+`revoked_reason='rotated'` and inserts a new row in the same `family_id` with `parent_session_id` pointing to the old row.
+- **Reuse detected**: presenting a refresh token whose row already has `revoked_reason='rotated'` → the entire `family_id` is revoked with `reason='reuse_detected'`.
+- **Logout**: `SessionService.RevokeBySid(sid, caller, 'logged_out')`. Idempotent.
+- **Logout all**: `SessionService.RevokeAllForUser(userId, caller, 'logged_out_all')`.
+- **Admin revoke**: `SessionService.RevokeBySid(sid, admin, 'admin_revoked')`.
+- **Mission issue**: `MissionTokenService.Issue` inserts row with `class='mission'`, `aircraft_id` set, `refresh_hash=null`, `expires_at = now + planned_duration_h`. **Before** signing the access token, prior mission rows for that `aircraft_id` are revoked with `reason='aircraft_reconnected'` (also called from successful login of a `CompanionPC` user).
+
+## Table: `audit_events` *(AZ-537 + AZ-534)*
+
+Append-only log used by the per-account sliding-window rate limit (AZ-537 AC-2) and as evidence for security audits.
+
+### Columns
+
+| Column | Type | Nullable | Default | Description |
+|--------|------|----------|---------|-------------|
+| `id` | `bigserial` | No | identity | PK |
+| `event_type` | `varchar(64)` | No | — | One of: `login_failed`, `login_success`, `login_lockout`, `mfa_enroll`, `mfa_confirm`, `mfa_disable`, `mfa_login_success`, `mfa_login_failed`, `mfa_recovery_used` |
+| `occurred_at` | `timestamp` | No | `now()` | |
+| `email` | `varchar(160)` | Yes | null | Lowercase normalised on insert |
+| `ip` | `varchar(64)` | Yes | null | `HttpContext.Connection.RemoteIpAddress` |
+| `metadata` | `text` | Yes | null | Reserved (no current writer) |
+
+### Indexes
+
+| Index | Columns |
+|-------|---------|
+| `audit_events_pkey` | `id` |
+| `audit_events_event_type_email_idx` | `(event_type, email, occurred_at DESC)` |

 ### Permissions

 | Role | Privileges |
 |------|-----------|
-| `azaion_reader` | SELECT on `users` |
-| `azaion_admin` | SELECT, INSERT, UPDATE, DELETE on `users` |
-| `azaion_superadmin` | Superuser (DB owner) |
+| `azaion_admin` | INSERT, SELECT, USAGE+SELECT on the sequence |
+| `azaion_reader` | SELECT |

-### Seed Data
+> **Retention**: not yet partitioned. With ~50 events/user/day × ~5000 users × 365 d this is ~14 GB/yr; consider time-partition + 90-day archive in a future cycle.

-Two default users (from `env/db/02_structure.sql`):
+## Table: `detection_classes`

-| Email | Role |
-|-------|------|
-| `admin@azaion.com` | `ApiAdmin` |
-| `uploader@azaion.com` | `ResourceUploader` |
+Unchanged in cycle 2. See `_docs/03_implementation/batch_06_report.md` for the original AZ-513 spec.
+
+## ORM Mapping (linq2db)
+
+Column names auto-converted from PascalCase → snake_case via `AzaionDbSchemaHolder`. Special mappings introduced in cycle 2:
+
+- `Session.RevokedReason` → enum-like text constants in `SessionRevokedReasons` (string-keyed; not a Postgres enum)
+- `Session.Class` → string constants in `SessionClasses` (`"interactive"`, `"mission"`)
+- `User.MfaRecoveryCodes` → `jsonb` via `Newtonsoft.Json` serialization (List<string> on the read path; the persisted shape is `[{ hash, used_at }]`)
+- `AuditEvent.EventType` → string constants in `AuditEventTypes`
+- `User.Role` → text via `Enum.Parse` (now also recognises `Service`)
+
+## Permissions (post-cycle-2)
+
+| Role | Tables | Notes |
+|------|--------|-------|
+| `azaion_reader` | SELECT on `users`, `sessions`, `audit_events`, `detection_classes` | Used by the read-only `IDbFactory.Run` path |
+| `azaion_admin` | SELECT/INSERT/UPDATE/DELETE on `users`; SELECT/INSERT/UPDATE on `sessions`; SELECT/INSERT on `audit_events`; full DML on `detection_classes` | Used by `IDbFactory.RunAdmin`. Note: no `DELETE` on `sessions` — revocation is logical via `revoked_at` |
+| `azaion_superadmin` | DB owner | Migrations only |

 ## Schema Migration History

 Schema is managed via SQL scripts in `env/db/`:

-1. `00_install.sh` — PostgreSQL installation and configuration
-2. `01_permissions.sql` — Role creation (superadmin, admin, reader)
-3. `02_structure.sql` — Table creation + seed data
-4. `03_add_timestamp_columns.sql` — Adds `created_at`, `last_login`, `is_enabled` columns
+| File | Cycle | Description |
+|------|-------|-------------|
+| `00_install.sh` | baseline | Postgres install + roles |
+| `01_permissions.sql` | baseline | Role grants |
+| `02_structure.sql` | baseline | `users` table + seed data (`admin@azaion.com`, `uploader@azaion.com`) |
+| `03_add_timestamp_columns.sql` | baseline | `created_at`, `last_login`, `is_enabled` |
+| `04_detection_classes.sql` | cycle 1 (AZ-513) | `detection_classes` |
+| `06_users_email_unique.sql` | post-cycle-1 | Security audit F-3: UNIQUE on `users.email` |
+| `07_auth_lockout_and_audit.sql` | cycle 2 (AZ-537) | `users.failed_login_count`, `users.lockout_until`, `audit_events` |
+| `08_sessions.sql` | cycle 2 (AZ-531) | `sessions` table + indexes |
+| `09_sessions_logout_and_mission.sql` | cycle 2 (AZ-535+533) | `sessions.revoked_by_user_id`, `class`, `aircraft_id`; relax `refresh_hash NOT NULL`; aircraft + revoked_at indexes |
+| `10_users_mfa.sql` | cycle 2 (AZ-534) | `users.mfa_*`, `sessions.mfa_authenticated` |

-No ORM migration framework is used. Schema changes are applied manually via SQL scripts.
+No ORM migration framework is used — scripts are applied in numeric order by `env/db/00_install.sh`. Numbers are not contiguous (`05` is missing) by design — kept as gaps so cherry-picks land in their original slot.

-## UserConfig JSON Schema
+## UserConfig JSON Schema (unchanged)

 ```json
 {
@@ -87,10 +226,9 @@ No ORM migration framework is used. Schema changes are applied manually via SQL
 }
 ```

-Stored in the `user_config` column. Deserialized to `UserConfig` → `UserQueueOffsets` on read. Default empty `UserConfig` is created when the field is null or empty.
+## Observations / Caveats

-## Observations
-
- The `hardware_hash` column exists in the DDL but is not referenced in application code. The application stores the raw hardware string in `hardware` and computes hashes at runtime.
- No unique constraint on `email` column in the DDL — uniqueness is enforced at the application level (`UserService.RegisterUser` checks for duplicates before insert).
- `user_config` is limited to `varchar(512)`, which could be insufficient if queue offsets grow or additional config fields are added.
+- `users.user_config` is still `varchar(512)`. With cycle 2 not adding to UserConfig, this is unchanged but remains a future-growth concern.
+- `sessions.refresh_hash` UNIQUE INDEX accepts multiple NULLs (Postgres semantics) — that's intentional for mission rows.
+- `audit_events` has no FK to `users` because it must survive user deletion (post-incident forensics).
+- The `Service` role is data-only on the user table; no provisioning UI exists yet — verifier accounts are seeded out-of-band.
@@ -1,20 +1,92 @@
-# Flow: User Login
+# Flow: User Login (dual token + MFA)
+
+> **Cycle 2 (2026-05-14)**: rebuilt around the AZ-531 + AZ-532 + AZ-534 + AZ-536 + AZ-537 stack. Single-token, SHA-384, HS256 path is gone. See `_docs/02_document/system-flows.md` F1 for the full narrative; this file is the canonical sequence diagram.

 ```mermaid
 sequenceDiagram
    participant Client
+    participant Mid as RateLimiter (per-IP, AZ-537)
    participant API as Admin API
    participant US as UserService
+    participant Sec as Security (Argon2id, AZ-536)
+    participant AL as AuditLog
+    participant Mfa as MfaService
+    participant RT as RefreshTokenService
+    participant Auth as AuthService (ES256, AZ-532)
+    participant SS as SessionService
    participant DB as PostgreSQL
-    participant Auth as AuthService

-    Client->>API: POST /login {email, password}
+    Client->>Mid: POST /login {email, password}
+    Mid->>Mid: per-IP sliding-window check
+    alt no permits
+        Mid-->>Client: 429 + Retry-After
+    end
+    Mid->>API: forward
    API->>US: ValidateUser(request)
-    US->>DB: SELECT user WHERE email = ?
-    DB-->>US: User record
-    US->>US: Compare password hash (SHA-384)
-    US-->>API: User entity
-    API->>Auth: CreateToken(user)
-    Auth-->>API: JWT string (HMAC-SHA256)
-    API-->>Client: 200 OK {token}
+    US->>DB: SELECT users WHERE email = ?
+    US->>AL: CountRecentFailedLogins(email, window)
+    alt account locked OR per-account threshold exceeded
+        US-->>API: AccountLocked / LoginRateLimited (RetryAfterSeconds)
+        API-->>Client: 423 / 429 + Retry-After
+    end
+    US->>Sec: VerifyPassword(presented, stored)
+    alt VerifyResult.Ok=false
+        US->>AL: RecordLoginFailed
+        US->>DB: UPDATE failed_login_count++; lockout_until = now + LockoutSeconds (if newly over)
+        US-->>API: WrongPassword (or NoEmailFound)
+        API-->>Client: 409
+    end
+    alt VerifyResult.NeedsRehash=true (legacy SHA-384)
+        US->>Sec: HashPassword (Argon2id)
+        US->>DB: UPDATE password_hash (lazy migrate)
+    end
+    US->>AL: RecordLoginSuccess
+    US->>DB: UPDATE failed_login_count = 0, lockout_until = NULL, last_login = now
+    US-->>API: User
+
+    alt user.MfaEnabled
+        API->>Mfa: IssueMfaStepToken(userId)
+        Mfa-->>API: ES256 JWT (mfa_pending=true, audience=mfa-step, ~5 min)
+        API-->>Client: 200 OK MfaRequiredResponse {mfa_required, mfa_token, expires_in: 300}
+
+        Note over Client,API: --- second factor ---
+        Client->>Mid: POST /login/mfa {mfa_token, code}
+        Mid->>Mid: per-IP sliding-window check
+        Mid->>API: forward
+        API->>Mfa: ValidateMfaStepToken(mfa_token) -> userId
+        API->>US: GetById(userId) -> User
+        API->>Mfa: VerifyForLogin(userId, code)
+        Mfa->>DB: TOTP verify decrypted mfa_secret OR consume recovery code
+        Mfa->>AL: RecordMfaLoginSuccess (or MfaRecoveryUsed)
+        Mfa-->>API: amr = ["pwd","mfa"] (+ "recovery" if used)
+        API->>RT: IssueForNewLogin(userId, mfaAuthenticated=true)
+        RT->>DB: INSERT INTO sessions (id, family_id=id, refresh_hash=SHA256(opaque), expires_at, mfa_authenticated=true)
+        RT-->>API: (opaqueRefreshToken, Session)
+        API->>Auth: CreateToken(user, sid=Session.Id, jti, amr=["pwd","mfa"])
+        Auth-->>API: AccessToken (ES256)
+        opt user.Role == CompanionPC
+            API->>SS: RevokeMissionsForAircraft(user.Id)
+        end
+        API-->>Client: 200 OK LoginResponse {AccessToken, AccessExp, RefreshToken, RefreshExp}
+    else
+        API->>RT: IssueForNewLogin(userId, mfaAuthenticated=false)
+        RT->>DB: INSERT INTO sessions (..., mfa_authenticated=false)
+        RT-->>API: (opaqueRefreshToken, Session)
+        API->>Auth: CreateToken(user, sid=Session.Id, jti, amr=["pwd"])
+        Auth-->>API: AccessToken (ES256)
+        opt user.Role == CompanionPC
+            API->>SS: RevokeMissionsForAircraft(user.Id)
+        end
+        API-->>Client: 200 OK LoginResponse {AccessToken, AccessExp, RefreshToken, RefreshExp}
+    end
 ```
+
+## Related diagrams (cycle 2)
+
+- `flow_refresh_token.md` *(see system-flows.md F11)*
+- `flow_logout_revocation.md` *(see system-flows.md F12)*
+- `flow_mission_token.md` *(see system-flows.md F13)*
+- `flow_mfa_lifecycle.md` *(see system-flows.md F14)*
+- `flow_revocation_snapshot.md` *(see system-flows.md F15)*
+
+These are documented inline in `system-flows.md` rather than as standalone files; this `flow_login.md` is kept as a separate file because it is referenced from multiple ADRs and the security report.
@@ -3,7 +3,7 @@
 **Language**: csharp
 **Layout Convention**: solution-flat (legacy — pre-`src/` convention)
 **Root**: `./` (csproj folders sit at workspace root)
-**Last Updated**: 2026-05-13
+**Last Updated**: 2026-05-14 *(refreshed for cycle 2 Auth Modernization — AZ-531..AZ-538)*

 ## Layout Rules

@@ -50,12 +50,12 @@ These come from `_docs/02_document/components/` and exist for reading the codeba

 | # | Sub-component        | Primary file locations |
 |---|----------------------|------------------------|
-| 1 | Data Layer           | `Azaion.Common/Database/`, `Azaion.Common/Configs/`, `Azaion.Common/Entities/` (incl. `DetectionClass.cs` added cycle 1; `Resource.cs` added then removed in same cycle — see post-cycle-1 revert) |
-| 2 | User Management      | `Azaion.Services/UserService.cs` (incl. `RegisterDevice` added cycle 1 / AZ-196 — calls `RegisterUser` end-to-end after security-audit consolidation, finding F-3), `Azaion.Common/Requests/Register{User,DeviceResponse}.cs`, `LoginRequest.cs`, `SetUserQueueOffsetsRequest.cs` |
-| 3 | Auth & Security      | `Azaion.Services/AuthService.cs`, `Azaion.Services/Security.cs` (post-cycle-2 — only `ToHash` remains; `GetApiEncryptionKey` / `EncryptTo` / `DecryptTo` removed with the encrypted-download endpoint), `Azaion.Services/Cache.cs` |
+| 1 | Data Layer           | `Azaion.Common/Database/`, `Azaion.Common/Configs/` (incl. cycle-2 `AuthConfig.cs` + `JwtConfig.cs` rebuilt for ES256 + new `SessionConfig`), `Azaion.Common/Entities/` (incl. cycle-1 `DetectionClass.cs`; cycle-2 `Session.cs` + `AuditEvent.cs`; `User.cs` extended with lockout + MFA columns; `RoleEnum.cs` + `Service = 60`) |
+| 2 | User Management      | `Azaion.Services/UserService.cs` (cycle-2 — Argon2id verify/hash + lazy migration + lockout + per-account rate-limit checks; new dependencies on `IAuditLog`, `IOptions<AuthConfig>`), `Azaion.Common/Requests/Register{User,DeviceResponse}.cs`, `LoginRequest.cs`, `LoginResponse.cs` *(new — AZ-531)*, `MfaRequests.cs` *(new — AZ-534)*, `MissionSessionRequest.cs` *(new — AZ-533)*, `SetUserQueueOffsetsRequest.cs` |
+| 3 | Auth & Security      | `Azaion.Services/AuthService.cs` (cycle-2 — ES256 + `AccessToken` record + sid/jti/amr claims), `Azaion.Services/Security.cs` (cycle-2 — Argon2id `HashPassword`/`VerifyPassword`; `ToHash` deleted), `Azaion.Services/RefreshTokenService.cs` *(new — AZ-531)*, `Azaion.Services/SessionService.cs` *(new — AZ-535)*, `Azaion.Services/MfaService.cs` *(new — AZ-534)*, `Azaion.Services/MissionTokenService.cs` *(new — AZ-533)*, `Azaion.Services/JwtSigningKeyProvider.cs` *(new — AZ-532)*, `Azaion.Services/AuditLog.cs` *(new — AZ-537)*, `Azaion.Services/Cache.cs` |
 | 4 | Resource Management  | `Azaion.Services/ResourcesService.cs` (`GetResourceRequest.cs` removed in cycle 2 with `POST /resources/get`; `SetHWRequest.cs` removed by AZ-197; `ResourceUpdateService.cs` + `GetUpdateRequest.cs` + `PublishResourceRequest.cs` removed when AZ-183 was reverted) |
 | 4b | Detection Classes    | `Azaion.Services/DetectionClassService.cs` + `Azaion.Common/Requests/{Create,Update}DetectionClassRequest.cs` (added cycle 1 / AZ-513) |
-| 5 | Admin API (HTTP)     | `Azaion.AdminApi/Program.cs`, `Azaion.AdminApi/BusinessExceptionHandler.cs`, `Azaion.AdminApi/appsettings*.json` |
+| 5 | Admin API (HTTP)     | `Azaion.AdminApi/Program.cs` (cycle-2 — significantly expanded: HSTS / HTTPS redirect, RateLimiter, DataProtection, eight new endpoints, `IssueDualTokens` + `ParseSidClaim`/`ParseUserIdClaim` helpers), `Azaion.AdminApi/BusinessExceptionHandler.cs` (cycle-2 — per-enum status mapping + `Retry-After` header), `Azaion.AdminApi/appsettings*.json` |

 ## Allowed Dependencies (csproj layering)

@@ -5,28 +5,43 @@ Application entry point: configures DI, middleware, authentication, authorizatio

 ## Public Interface (HTTP Endpoints)

-> **Cycle 1 (2026-05-13) note** — endpoint surface changed by AZ-513 (detection-class CRUD), AZ-196 (device auto-registration), AZ-197 (hardware-binding removal). AZ-183 (OTA update check + publish) was reverted later the same day after the security audit (finding F-1) — the OTA delivery model itself was deemed obsolete; see `_docs/05_security/security_report.md` for context. The table reflects the post-cycle-1 state including that revert.
+> **Cycle 1 (2026-05-13) note** — endpoint surface changed by AZ-513 (detection-class CRUD), AZ-196 (device auto-registration), AZ-197 (hardware-binding removal). AZ-183 (OTA update check + publish) was reverted later the same day after the security audit (finding F-1).
 >
-> **Cycle 2 (2026-05-14) note** — three more endpoints were removed as obsolete: `POST /resources/get/{dataFolder?}`, `GET /resources/get-installer`, `GET /resources/get-installer/stage`. The encrypted-download support stack (`Security.GetApiEncryptionKey` / `EncryptTo` / `DecryptTo`, `ResourcesService.GetEncryptedResource` / `GetInstaller`, `GetResourceRequest` DTO, `WrongResourceName = 50` enum value, `ResourcesConfig.SuiteInstallerFolder` / `SuiteStageInstallerFolder`) went with them. ADR-003 in `architecture.md` was retired in the same change.
+> **Cycle 2 (2026-05-14) note A** — three resource endpoints removed as obsolete: `POST /resources/get/{dataFolder?}`, `GET /resources/get-installer`, `GET /resources/get-installer/stage`. The encrypted-download support stack went with them. ADR-003 in `architecture.md` was retired.
+>
+> **Cycle 2 (2026-05-14) note B (auth modernization)** — eight endpoints added or replaced as part of Epic AZ-529 (Auth Modernization) + AZ-530 (CMMC Hardening). The `/login` shape is now dual-token (access + refresh) when MFA is off, or `MfaRequiredResponse` when MFA is enabled. CORS dropped the cleartext origin (AZ-538). HSTS + HTTPS redirection are wired in non-Development environments. Per-IP sliding-window rate limit added to `/login` (and `/login/mfa`). Public-key JWKS feed live at `/.well-known/jwks.json` (AZ-532).

-| Method | Path | Auth | Summary | Cycle 1 origin |
-|--------|------|------|---------|----------------|
-| POST | `/login` | Anonymous | Validates credentials, returns JWT token | — |
-| POST | `/users` | ApiAdmin | Creates a new user | — |
-| POST | `/devices` | ApiAdmin | Creates a CompanionPC device user (auto serial / email / 32-hex password) | AZ-196 |
-| GET | `/users/current` | Any authenticated | Returns current user from JWT claims | — |
-| GET | `/users` | ApiAdmin | Lists users with optional email/role filters | — |
-| PUT | `/users/queue-offsets/set` | Any authenticated | Updates user's queue offsets | — |
-| PUT | `/users/{email}/set-role/{role}` | ApiAdmin | Changes a user's role | — |
-| PUT | `/users/{email}/enable` | ApiAdmin | Enables a user account | — |
-| PUT | `/users/{email}/disable` | ApiAdmin | Disables a user account | — |
-| DELETE | `/users/{email}` | ApiAdmin | Removes a user | — |
-| POST | `/resources/{dataFolder?}` | Any authenticated | Uploads a resource file | — |
-| GET | `/resources/list/{dataFolder?}` | Any authenticated | Lists files in a resource folder | — |
-| POST | `/resources/clear/{dataFolder?}` | ApiAdmin | Clears a resource folder | — |
-| POST | `/classes` | ApiAdmin | Creates a detection class | AZ-513 |
-| PATCH | `/classes/{id:int}` | ApiAdmin | Updates a detection class (partial-merge) | AZ-513 |
-| DELETE | `/classes/{id:int}` | ApiAdmin | Deletes a detection class | AZ-513 |
+| Method | Path | Auth | Summary | Cycle origin |
+|--------|------|------|---------|--------------|
+| GET | `/health/live` | Anonymous | Liveness check (`Cache-Control: no-store`); excluded from Swagger | AZ-510 |
+| GET | `/health/ready` | Anonymous | Readiness check — pings both DB connections with a 2-s timeout; 503 with reason on failure | AZ-510 |
+| POST | `/login` | Anonymous + per-IP rate limit | Validates credentials. Returns `LoginResponse` (access + refresh) when MFA is off, `MfaRequiredResponse` when MFA is enabled. | AZ-531 / AZ-534 / AZ-537 |
+| POST | `/login/mfa` | Anonymous + per-IP rate limit | Second-factor verification (TOTP or recovery code). Returns `LoginResponse`. | AZ-534 |
+| POST | `/token/refresh` | Anonymous (token in body) | Rotates a refresh token; returns a fresh `LoginResponse`. Reuse-detection kills the family. | AZ-531 |
+| POST | `/logout` | Authenticated | Revokes the caller's current session (idempotent — returns `{ alreadyRevoked }`). | AZ-535 |
+| POST | `/logout/all` | Authenticated | Revokes every active session for the caller's user (returns `{ revoked: N }`). | AZ-535 |
+| POST | `/sessions/{sid:guid}/revoke` | ApiAdmin | Admin revoke-by-session-id. | AZ-535 |
+| GET | `/sessions/revoked` | revocationReader (Service or ApiAdmin) | Verifier-poll snapshot of revoked-but-not-yet-expired sessions. `Cache-Control: no-cache`; `since` clamped to `now - 12h`. | AZ-535 |
+| POST | `/sessions/mission` | Authenticated | Mints a long-lived no-refresh mission token bound to one aircraft. AZ-533 AC-6 step-up MFA gate is a TODO comment until org-wide MFA adoption. | AZ-533 |
+| POST | `/users/me/mfa/enroll` | Authenticated | Returns TOTP secret + otpauth URL + QR PNG + 10 recovery codes (ONCE). | AZ-534 |
+| POST | `/users/me/mfa/confirm` | Authenticated | Validates one TOTP code and flips `mfa_enabled=true`. | AZ-534 |
+| POST | `/users/me/mfa/disable` | Authenticated | Removes MFA (requires password + valid code). | AZ-534 |
+| GET | `/.well-known/jwks.json` | Anonymous (excluded from Swagger) | Public JWKS feed for verifiers; `Cache-Control: public, max-age=3600`. | AZ-532 |
+| POST | `/users` | ApiAdmin | Creates a new user. | — |
+| POST | `/devices` | ApiAdmin | Creates a CompanionPC device user (auto serial / email / 32-hex password). | AZ-196 |
+| GET | `/users/current` | Any authenticated | Returns current user from JWT claims. | — |
+| GET | `/users` | ApiAdmin | Lists users with optional email/role filters. | — |
+| PUT | `/users/queue-offsets/set` | Any authenticated | Updates user's queue offsets. | — |
+| PUT | `/users/{email}/set-role/{role}` | ApiAdmin | Changes a user's role. | — |
+| PUT | `/users/{email}/enable` | ApiAdmin | Enables a user account. | — |
+| PUT | `/users/{email}/disable` | ApiAdmin | Disables a user account. | — |
+| DELETE | `/users/{email}` | ApiAdmin | Removes a user. | — |
+| POST | `/resources/{dataFolder?}` | Any authenticated | Uploads a resource file. | — |
+| GET | `/resources/list/{dataFolder?}` | Any authenticated | Lists files in a resource folder. | — |
+| POST | `/resources/clear/{dataFolder?}` | ApiAdmin | Clears a resource folder. | — |
+| POST | `/classes` | ApiAdmin | Creates a detection class. | AZ-513 |
+| PATCH | `/classes/{id:int}` | ApiAdmin | Updates a detection class (partial-merge). | AZ-513 |
+| DELETE | `/classes/{id:int}` | ApiAdmin | Deletes a detection class. | AZ-513 |

 ### Removed endpoints

@@ -34,79 +49,99 @@ The following endpoints have been removed and now return `404`:

 | Method | Path | Removed in | Reason |
 |--------|------|------------|--------|
-| PUT | `/users/hardware/set` | cycle 1 (AZ-197) | hardware-binding feature deleted (no fielded clients in target architecture) |
-| POST | `/resources/check` | cycle 1 (AZ-197) | was the hardware-binding side-effect probe; no remaining purpose |
-| POST | `/get-update` | post-cycle-1 (AZ-183 reverted) | security audit F-1: endpoint disclosed plaintext per-resource encryption keys to any authenticated caller; the underlying installer-distribution flow is itself obsolete |
-| POST | `/resources/publish` | post-cycle-1 (AZ-183 reverted) | same revert as `/get-update` — the publish counterpart of the OTA flow |
-| POST | `/resources/get/{dataFolder?}` | cycle 2 (2026-05-14) | obsolete — per-user encrypted-download flow no longer used by any client; ADR-003 retired |
-| GET | `/resources/get-installer` | cycle 2 (2026-05-14) | obsolete — installer-shipping era is over (browser SaaS + fTPM Jetsons) |
-| GET | `/resources/get-installer/stage` | cycle 2 (2026-05-14) | same as `/resources/get-installer` |
+| PUT | `/users/hardware/set` | cycle 1 (AZ-197) | hardware-binding feature deleted |
+| POST | `/resources/check` | cycle 1 (AZ-197) | hardware-binding side-effect probe |
+| POST | `/get-update` | post-cycle-1 (AZ-183 reverted) | security audit F-1 |
+| POST | `/resources/publish` | post-cycle-1 (AZ-183 reverted) | OTA flow obsolete |
+| POST | `/resources/get/{dataFolder?}` | cycle 2 | obsolete; ADR-003 retired |
+| GET | `/resources/get-installer` | cycle 2 | installer-shipping era over |
+| GET | `/resources/get-installer/stage` | cycle 2 | same as above |

 ## Internal Logic

 ### DI Registration
+- `IJwtSigningKeyProvider` → `JwtSigningKeyProvider` (Singleton; eagerly built before `app.Build()` so `JwtBearer` and DI share one instance) — **AZ-532**
 - `IUserService` → `UserService` (Scoped)
 - `IAuthService` → `AuthService` (Scoped)
+- `IRefreshTokenService` → `RefreshTokenService` (Scoped) — **AZ-531**
+- `ISessionService` → `SessionService` (Scoped) — **AZ-535**
+- `IMissionTokenService` → `MissionTokenService` (Scoped) — **AZ-533**
+- `IMfaService` → `MfaService` (Scoped) — **AZ-534**
 - `IResourcesService` → `ResourcesService` (Scoped)
- `IDetectionClassService` → `DetectionClassService` (Scoped) — added by AZ-513
+- `IDetectionClassService` → `DetectionClassService` (Scoped)
+- `IAuditLog` → `AuditLog` (Scoped) — **AZ-537 / AZ-534**
 - `IDbFactory` → `DbFactory` (Singleton)
 - `ICache` → `MemoryCache` (Scoped)
 - `LazyCache` via `AddLazyCache()`
- FluentValidation validators auto-discovered from `RegisterUserValidator` assembly (also picks up `CreateDetectionClassRequest`, `UpdateDetectionClassRequest` validators introduced in cycle 1)
+- ASP.NET Core `DataProtection` — `SetApplicationName("Azaion.AdminApi")`; if `DataProtection:KeysFolder` is set, persisted to filesystem (production requirement for MFA-secret durability) — **AZ-534**
+- FluentValidation validators auto-discovered from `RegisterUserValidator` assembly
 - `BusinessExceptionHandler` registered as exception handler

 ### Middleware Pipeline
-1. Swagger (dev only)
-2. CORS (`AdminCorsPolicy`)
-3. Authentication (JWT Bearer)
-4. Authorization
-5. URL rewrite: root `/` → `/swagger`
-6. Exception handler
+1. Swagger (Development only)
+2. **HSTS + HTTPS redirection (non-Development only)** — AZ-538
+3. CORS (`AdminCorsPolicy`)
+4. Authentication (JWT Bearer with `ValidAlgorithms = [ES256]` and an `IssuerSigningKeyResolver` that picks by `kid` from `IJwtSigningKeyProvider.All`)
+5. Authorization
+6. **Rate limiter (`UseRateLimiter`)** — AZ-537
+7. URL rewrite: root `/` → `/swagger`
+8. Exception handler

 ### Authorization Policies
 - `apiAdminPolicy`: requires `RoleEnum.ApiAdmin` role
+- `revocationReaderPolicy`: requires `RoleEnum.Service` OR `RoleEnum.ApiAdmin` (gates `/sessions/revoked`) — **AZ-535**

-> The `apiUploaderPolicy` (`RoleEnum.ResourceUploader` OR `ApiAdmin`) was added by AZ-183 and removed in the same cycle when the OTA endpoints it guarded were retired (see "Removed in cycle 1" above). `RoleEnum.ResourceUploader` itself remains as a data value (the seed `uploader@azaion.com` still uses it) but is no longer wired to any endpoint policy.
+### Rate Limit Policies
+- `LoginPerIpPolicy = "login-per-ip"` — sliding-window limiter keyed on `RemoteIpAddress`. Configured from `AuthConfig.RateLimit.PerIpPermitLimit` / `PerIpWindowSeconds`. On rejection, sets `Retry-After` from the `RetryAfter` lease metadata. Applied to `/login` and `/login/mfa`.

 ### Configuration Sections
- `JwtConfig` — JWT signing/validation
+- `JwtConfig` — JWT signing/validation (Issuer, Audience, KeysFolder, ActiveKid, AccessTokenLifetimeMinutes)
+- `SessionConfig` — refresh-token sliding/absolute window (RefreshSlidingHours, RefreshAbsoluteHours) — **AZ-531**
+- `AuthConfig` — rate-limit and lockout knobs — **AZ-537**
 - `ConnectionStrings` — DB connections
- `ResourcesConfig` — file storage path (`ResourcesFolder`); the installer subfolders were dropped in cycle 2 along with the installer endpoints
+- `ResourcesConfig` — file storage path

 ### Kestrel
- Max request body size: 200 MB (for file uploads)
+- Max request body size: 200 MB

 ### Logging
 - Serilog: console + rolling file (`logs/log.txt`)

 ### CORS
- Allowed origins: `https://admin.azaion.com`, `http://admin.azaion.com`
- All methods and headers allowed
- Credentials allowed
+- Allowed origin: `https://admin.azaion.com` (the cleartext `http://` origin was dropped by AZ-538)
+- All methods and headers allowed; credentials allowed
+
+### Helpers
+Local static helpers used by logout / mission endpoints:
+- `ParseSidClaim(ClaimsPrincipal)` — extracts the `sid` claim; throws `InvalidRefreshToken` (401) if missing/malformed.
+- `ParseUserIdClaim(ClaimsPrincipal)` — extracts `NameIdentifier`; same error semantics.
+- `IssueDualTokens(...)` — shared by `/login` and `/login/mfa`; calls `IRefreshTokenService.IssueForNewLogin`, `IAuthService.CreateToken`, plus `ISessionService.RevokeMissionsForAircraft` when the caller is `RoleEnum.CompanionPC` (AZ-533 AC-4 reconnect trigger).

 ## Dependencies
-All services, configs, entities, and request types from Azaion.Common and Azaion.Services.
+All services, configs, entities, and request types from `Azaion.Common` and `Azaion.Services`. New dependencies wired in cycle 2: `Microsoft.AspNetCore.RateLimiting`, `Microsoft.AspNetCore.DataProtection`.

 ## Consumers
-None — this is the application entry point.
+None — application entry point.

 ## Data Models
 None defined here.

 ## Configuration
-Reads `JwtConfig`, `ConnectionStrings`, `ResourcesConfig` from `IConfiguration`.
+Reads `JwtConfig`, `SessionConfig`, `AuthConfig`, `ConnectionStrings`, `ResourcesConfig` from `IConfiguration`. Optional `DataProtection:KeysFolder` for MFA-secret durability.

 ## External Integrations
 - PostgreSQL (via DI-registered `DbFactory`)
- Local filesystem (via `ResourcesService`)
+- Local filesystem (via `ResourcesService` and `JwtSigningKeyProvider` for PEM keys)

 ## Security
- JWT Bearer authentication with full validation (issuer, audience, lifetime, signing key)
- Role-based authorization policies
- CORS restricted to `admin.azaion.com`
- Request body limit of 200 MB
- Antiforgery disabled for resource upload endpoint
- Password sent via POST body (not URL)
+- JWT Bearer with full validation: `ValidateIssuer`, `ValidateAudience`, `ValidateLifetime`, `ValidateIssuerSigningKey`, `ValidAlgorithms = [ES256]` (AZ-532 AC-5).
+- Issuer signing keys resolved per-`kid` via `IJwtSigningKeyProvider`; supports rotation overlap.
+- Public JWKS endpoint exposes only public components (`x`/`y` for EC); `Cache-Control: public, max-age=3600`.
+- Per-IP sliding-window rate limit on `/login` and `/login/mfa` (AZ-537).
+- HSTS (1 year, includeSubDomains, preload) + HTTPS redirect in non-Development envs (AZ-538).
+- CORS restricted to HTTPS origin only (AZ-538).
+- DataProtection key folder must be a persistent volume in Production so encrypted MFA secrets survive restarts (AZ-534 known operational requirement; **carry-forward F3** asks for a startup warning when running in Production with the folder unset).
+- Role-based authorization for admin endpoints; new `Service` role gates the verifier-poll feed.

 ## Tests
-None directly; tested indirectly through integration tests.
+None directly; tested through `e2e/Azaion.E2E/Tests/` (Login, RefreshToken, RateLimitLockout, Logout, Jwks, MissionToken, MfaEnrollment, MfaLogin, PasswordHashing).
@@ -13,31 +13,54 @@ Custom exception type for domain-level errors, paired with an `ExceptionEnum` ca
 | `GetMessage` | `static string GetMessage(ExceptionEnum exEnum)` | Looks up human-readable message for an error code |

 ### ExceptionEnum
-| Value | Code | Description |
-|-------|------|-------------|
-| `NoEmailFound` | 10 | No such email found |
-| `EmailExists` | 20 | Email already exists |
-| `WrongPassword` | 30 | Passwords do not match |
-| `PasswordLengthIncorrect` | 32 | Password should be at least 12 characters (description text — actual validator threshold is 8 chars per `RegisterUserValidator`) |
-| `EmailLengthIncorrect` | 35 | Email is empty or invalid |
-| `WrongEmail` | 37 | (no description attribute) |
-| `UserDisabled` | 38 | User account is disabled |
-| `NoFileProvided` | 60 | No file provided |
+| Value | Code | Description | HTTP Status |
+|-------|------|-------------|-------------|
+| `NoEmailFound` | 10 | No such email found | 409 |
+| `EmailExists` | 20 | Email already exists | 409 |
+| `WrongPassword` | 30 | Passwords do not match | 409 |
+| `PasswordLengthIncorrect` | 32 | Password should be at least 12 characters | 409 |
+| `EmailLengthIncorrect` | 35 | Email is empty or invalid | 409 |
+| `WrongEmail` | 37 | (no description attribute) | 409 |
+| `UserDisabled` | 38 | User account is disabled | 409 |
+| `AccountLocked` | 50 | AZ-537 — account temporarily locked due to too many failed login attempts (carries `RetryAfterSeconds`) | **423 Locked** |
+| `LoginRateLimited` | 51 | AZ-537 — too many login attempts per account; try again later (carries `RetryAfterSeconds`) | **429 Too Many Requests** |
+| `InvalidRefreshToken` | 52 | AZ-531 — refresh token invalid / expired / revoked / reuse-detected | **401 Unauthorized** |
+| `SessionNotFound` | 53 | AZ-535 — admin tried to revoke a non-existent session | **404 Not Found** |
+| `InvalidMissionRequest` | 54 | AZ-533 — mission_id pattern fail or planned_duration_h out of bounds | **400 Bad Request** |
+| `AircraftNotFound` | 55 | AZ-533 — aircraft id missing or not a `CompanionPC` user | **400 Bad Request** |
+| `MfaAlreadyEnabled` | 56 | AZ-534 — `/users/me/mfa/enroll` called for a user that already has MFA on | **409 Conflict** |
+| `MfaNotEnrolling` | 57 | AZ-534 — confirm called without a prior enroll | **409 Conflict** |
+| `MfaNotEnabled` | 58 | AZ-534 — disable / verify-for-login called for a user without MFA | **409 Conflict** |
+| `InvalidMfaCode` | 59 | AZ-534 — TOTP code (and recovery code) failed to verify | **401 Unauthorized** |
+| `NoFileProvided` | 60 | No file provided | 409 |
+| `InvalidMfaToken` | 61 | AZ-534 — step-1 MFA token failed to validate (signature / audience / expiry) | **401 Unauthorized** |

-> **Cycle 1 (2026-05-13) note** — `HardwareIdMismatch = 40` and `BadHardware = 45` were removed by AZ-197 (admin-side hardware-binding cleanup). Codes 40 and 45 should NOT be reused for a different meaning — older clients may still surface "Hardware mismatch" UX strings keyed on the integer. `UserDisabled = 38` was added earlier (still part of the baseline). See `_docs/03_implementation/batch_06_report.md`.
+### RetryAfterSeconds
+
+| Member | Type | Description |
+|--------|------|-------------|
+| Constructor | `BusinessException(ExceptionEnum exEnum, int retryAfterSeconds)` | Cycle 2 (AZ-537) — sets `RetryAfterSeconds`, surfaced by `BusinessExceptionHandler` as a `Retry-After` response header. Used by `AccountLocked` (returns remaining lockout seconds) and `LoginRateLimited` (returns the window seconds). |
+| `RetryAfterSeconds` | `int?` | Optional cooldown hint; null when the exception was constructed without a window. |
+
+> **Cycle 1 (2026-05-13) note** — `HardwareIdMismatch = 40` and `BadHardware = 45` were removed by AZ-197. Codes 40 and 45 should NOT be reused.
 >
-> **Cycle 2 (2026-05-14) note** — `WrongResourceName = 50` was removed along with the `GetResourceRequest` validator (the only consumer). Code 50 should NOT be reused — gap kept per the cycle-1 lesson on retired numeric codes.
+> **Cycle 2 (2026-05-14) note** — `WrongResourceName = 50` was removed early in the cycle along with the `GetResourceRequest` validator. The integer 50 has since been **reused for `AccountLocked`** as part of AZ-537 (since the previous user-facing string "Wrong resource name" is no longer surfaced anywhere). This is the one deliberate exception to the "gap kept" lesson — the old code had no remaining client surface and the auth modernization wanted a tightly-clustered range of new codes.

 ## Internal Logic
-Static constructor eagerly loads all `ExceptionEnum` descriptions into a dictionary via `EnumExtensions.GetDescriptions<ExceptionEnum>()`. Messages are retrieved by dictionary lookup with fallback to `ToString()`.
+Static constructor eagerly loads all `ExceptionEnum` descriptions into a dictionary via `EnumExtensions.GetDescriptions<ExceptionEnum>()`. Messages are retrieved by dictionary lookup with fallback to `ToString()`. The two-arg constructor sets `RetryAfterSeconds` for the lockout / rate-limit paths.

 ## Dependencies
 - `EnumExtensions` — for `GetDescriptions<T>()`

 ## Consumers
- `BusinessExceptionHandler` — catches and serializes to HTTP 409 response
- `UserService` — throws for email/password validation failures (`NoEmailFound`, `WrongPassword`, `EmailExists`, `UserDisabled`)
+- `BusinessExceptionHandler` — catches and maps via `MapStatusCode`. The default mapping is 409; cycle 2 codes use a per-enum status map (`AccountLocked` → 423, `LoginRateLimited` → 429, refresh/MFA validation failures → 401, `SessionNotFound` → 404, mission validation failures → 400, MFA conflict states → 409). When `RetryAfterSeconds > 0` the handler also stamps a `Retry-After` response header.
+- `UserService` — throws for the auth path (`NoEmailFound`, `WrongPassword`, `EmailExists`, `UserDisabled`, `AccountLocked`, `LoginRateLimited`)
+- `RefreshTokenService` — throws `InvalidRefreshToken` on bad/expired/reuse-detected
+- `SessionService` — throws `SessionNotFound` for admin-revoke of missing sids
+- `MissionTokenService` — throws `InvalidMissionRequest`, `AircraftNotFound`
+- `MfaService` — throws `MfaAlreadyEnabled`, `MfaNotEnrolling`, `MfaNotEnabled`, `InvalidMfaCode`, `InvalidMfaToken`, `NoEmailFound`, `WrongPassword`
 - `ResourcesService` — throws `NoFileProvided` for missing file uploads
+- `Program.cs` `ParseSidClaim` / `ParseUserIdClaim` helpers — throw `InvalidRefreshToken` (401) on missing or malformed claims
 - FluentValidation validators — reference `ExceptionEnum` codes in `.WithErrorCode()`

 ## Data Models
@@ -50,7 +73,7 @@ None.
 None.

 ## Security
-Error codes are returned to the client via `BusinessExceptionHandler`. Codes are numeric and messages are user-facing.
+Error codes are returned to the client via `BusinessExceptionHandler` along with the per-enum HTTP status. The `Retry-After` header on lockout / rate-limit responses lets well-behaved clients back off without blind retries.

 ## Tests
 None.
@@ -0,0 +1,58 @@
+# Module: Azaion.Common.Configs.AuthConfig
+
+## Purpose
+Configuration POCO bundling the per-IP / per-account login rate-limit knobs and the consecutive-failure account-lockout policy. Bound from `appsettings.json` section `AuthConfig`.
+
+> Added in cycle 2 (2026-05-14) by AZ-537 (Epic AZ-530, CMMC AC.L2-3.1.8).
+
+## Public Interface
+
+### AuthConfig
+
+| Property | Type | Description |
+|----------|------|-------------|
+| `RateLimit` | `RateLimitOptions` | Per-IP and per-account login rate-limit windows. |
+| `Lockout` | `LockoutOptions` | Consecutive-failure threshold and lockout duration. |
+
+### RateLimitOptions
+
+| Property | Type | Default | Description |
+|----------|------|---------|-------------|
+| `PerIpPermitLimit` | `int` | 10 | Allowed login attempts per IP per `PerIpWindowSeconds`. Enforced by ASP.NET Core's built-in sliding-window limiter on `/login` (and `/login/mfa`). |
+| `PerIpWindowSeconds` | `int` | 60 | Window length for the per-IP limiter. |
+| `PerAccountPermitLimit` | `int` | 5 | Allowed *failed* login attempts per email per `PerAccountWindowSeconds`. Enforced by `UserService.ValidateUser` against `AuditLog.CountRecentFailedLogins`. |
+| `PerAccountWindowSeconds` | `int` | 300 | Window length for the per-account limiter (5 min). |
+
+### LockoutOptions
+
+| Property | Type | Default | Description |
+|----------|------|---------|-------------|
+| `MaxAttempts` | `int` | 10 | Consecutive failed logins that trigger lockout. Counter lives on `users.failed_login_count`. |
+| `DurationSeconds` | `int` | 900 | Lockout duration (15 min). Sets `users.lockout_until = now() + DurationSeconds`. |
+
+## Internal Logic
+None — pure data class.
+
+## Dependencies
+None.
+
+## Consumers
+- `Program.cs` — registers via `builder.Services.Configure<AuthConfig>(...)` and reads it eagerly to build the per-IP `SlidingWindowLimiter` partition.
+- `UserService.ValidateUser` — reads `RateLimit.PerAccountPermitLimit` / `PerAccountWindowSeconds` for the per-account rate limit and `Lockout.MaxAttempts` / `DurationSeconds` for lockout enforcement.
+
+## Data Models
+None.
+
+## Configuration
+Bound via `builder.Configuration.GetSection(nameof(AuthConfig))`. Override via env vars like `AuthConfig__Lockout__MaxAttempts=15`.
+
+## External Integrations
+None.
+
+## Security
+- Per-IP limit is in-memory (process-local); a multi-instance admin deployment would either need sticky-sessions on `/login` or a Redis-backed limiter (called out as a known upgrade path in `_docs/05_security/security_report.md`).
+- Per-account limit is DB-backed (via `audit_events`) so it survives process restarts and is consistent across instances.
+- Lockout precedence: a locked account returns 423 Locked even for a correct password until `lockout_until` passes (CMMC AC.L2-3.1.8 requires this).
+
+## Tests
+- `e2e/Azaion.E2E/Tests/RateLimitLockoutTests.cs` — covers AC-1..AC-6 of AZ-537 with the default values from this config.
@@ -1,38 +1,68 @@
-# Module: Azaion.Common.Configs.JwtConfig
+# Module: Azaion.Common.Configs.JwtConfig + SessionConfig

 ## Purpose
-Configuration POCO for JWT token generation parameters, bound from `appsettings.json` section `JwtConfig`.
+Configuration POCOs for JWT signing/validation and refresh-token TTLs. Bound from `appsettings.json` sections `JwtConfig` and `SessionConfig`. Both classes live in `Azaion.Common/Configs/JwtConfig.cs`.
+
+> **Cycle 2 (2026-05-14) note (AZ-531 / AZ-532)** — major reshape:
+> - HS256 shared-secret signing is gone. `Secret` is no longer read by any code path; the property is retained only as a temporary rollback escape hatch (AZ-532 spec).
+> - New: `KeysFolder` (PEM directory) and `ActiveKid` (currently-signing key id) for ES256.
+> - New: `AccessTokenLifetimeMinutes` (default 15) replaces the old `TokenLifetimeHours` (default 4) — short-lived access tokens are now paired with refresh-token rotation.
+> - New companion class `SessionConfig` carries refresh-token TTLs.

 ## Public Interface

-| Property | Type | Description |
-|----------|------|-------------|
-| `Issuer` | `string` | Token issuer claim |
-| `Audience` | `string` | Token audience claim |
-| `Secret` | `string` | HMAC-SHA256 signing key |
-| `TokenLifetimeHours` | `double` | Token expiry duration in hours |
+### JwtConfig
+
+| Property | Type | Default | Description |
+|----------|------|---------|-------------|
+| `Issuer` | `string` | (required) | Token `iss` claim. Validated by JwtBearer middleware. |
+| `Audience` | `string` | (required) | Token `aud` claim for interactive sessions. (Mission tokens override to `satellite-provider`; MFA step-1 tokens override to `azaion-mfa-step2`.) |
+| `KeysFolder` | `string` | `secrets/jwt-keys` | Directory containing one ES256 PEM per key. The kid is the filename without `.pem`. |
+| `ActiveKid` | `string?` | `null` | Kid currently used to sign new tokens. If null, falls back to the first PEM by ordinal filename order with a startup log warning. |
+| `AccessTokenLifetimeMinutes` | `int` | 15 | Access-token TTL. |
+
+### SessionConfig
+
+| Property | Type | Default | Description |
+|----------|------|---------|-------------|
+| `RefreshSlidingHours` | `int` | 8 | Each rotation extends `expires_at` by this many hours from `now`. |
+| `RefreshAbsoluteHours` | `int` | 12 | Family is rejected past this many hours since `family_started_at`, regardless of sliding rotations. |

 ## Internal Logic
-None — pure data class.
+None — pure data classes.

 ## Dependencies
 None.

 ## Consumers
- `Program.cs` — reads `JwtConfig` to configure JWT Bearer authentication middleware
- `AuthService.CreateToken` — uses Issuer, Audience, Secret, TokenLifetimeHours to build JWT tokens
+
+- `Program.cs`
+  - reads `JwtConfig` eagerly to fail-fast on missing Issuer/Audience and to construct the `JwtSigningKeyProvider` before `app.Build()`
+  - registers `Configure<JwtConfig>` and `Configure<SessionConfig>` for downstream injection
+- `JwtSigningKeyProvider` — reads `KeysFolder`, `ActiveKid`
+- `AuthService.CreateToken` — reads `Issuer`, `Audience`, `AccessTokenLifetimeMinutes`
+- `RefreshTokenService` — reads `SessionConfig.RefreshSlidingHours`, `RefreshAbsoluteHours`
+- `MfaService.IssueMfaStepToken` / `ValidateMfaStepToken` — reads `Issuer` (audience is hard-coded to `azaion-mfa-step2`)
+- `MissionTokenService.MintToken` — reads `Issuer` (audience is hard-coded to `satellite-provider`)

 ## Data Models
 None.

 ## Configuration
-Bound via `builder.Configuration.GetSection(nameof(JwtConfig))`. Expected env var: `ASPNETCORE_JwtConfig__Secret`.
+
+Bound via `builder.Configuration.GetSection(nameof(JwtConfig))` and `Configure<SessionConfig>`. Override via env vars:
+- `JwtConfig__Issuer=…`, `JwtConfig__Audience=…`, `JwtConfig__KeysFolder=/var/lib/azaion/jwt-keys`, `JwtConfig__ActiveKid=kid-2026-05-14`
+- `SessionConfig__RefreshSlidingHours=8`, `SessionConfig__RefreshAbsoluteHours=12`

 ## External Integrations
-None.
+Filesystem (read-only on `KeysFolder`).

 ## Security
-`Secret` is the symmetric signing key for all JWT tokens. Must be kept secret and sufficiently long for HMAC-SHA256.
+
+- Private signing keys live on disk only; the JWKS endpoint exports only public components. `chmod 600` is applied by `scripts/generate-jwt-key.sh`.
+- The legacy `Secret` field is retained but unused; remove on a follow-up cleanup ticket once the rollback window has closed.
+- `RefreshAbsoluteHours` is the hard cap on session lifetime — no rotation can extend past it. Bumping above 12 h needs a security review because it directly extends the leak-window of any one refresh token.

 ## Tests
-None.
+- `e2e/Azaion.E2E/Tests/JwksTests.cs` — exercises the rotation overlap (AC-3) by manipulating `KeysFolder` and `ActiveKid`.
+- `e2e/Azaion.E2E/Tests/RefreshTokenTests.cs` — exercises both the sliding and absolute caps (AC-4).
@@ -3,34 +3,42 @@
 ## Purpose
 linq2db `DataConnection` subclass representing the application's database context.

+> **Cycle 1 (2026-05-13)** — `DetectionClasses` ITable added (AZ-513).
+>
+> **Cycle 2 (2026-05-14)** — `AuditEvents` ITable added (AZ-537+534), `Sessions` ITable added (AZ-531+535+533+534).
+
 ## Public Interface

 | Member | Type | Description |
 |--------|------|-------------|
 | Constructor | `AzaionDb(DataOptions dataOptions)` | Initializes connection with pre-configured options |
-| `Users` | `ITable<User>` | Typed table accessor for the `users` table |
+| `Users` | `ITable<User>` | Typed accessor for `public.users` |
+| `DetectionClasses` | `ITable<DetectionClass>` | Typed accessor for `public.detection_classes` |
+| `AuditEvents` | `ITable<AuditEvent>` | **AZ-537+534** — typed accessor for `public.audit_events` |
+| `Sessions` | `ITable<Session>` | **AZ-531+535+533+534** — typed accessor for `public.sessions` (one row per refresh-token rotation; mission tokens live here too) |

 ## Internal Logic
-Delegates all connection management to the base `DataConnection` class. `Users` property calls `this.GetTable<User>()`.
+Delegates all connection management to the base `DataConnection` class. Each property calls `this.GetTable<T>()`. The actual column mapping and conversions live in `AzaionDbShemaHolder`.

 ## Dependencies
- `User` entity
+- `User`, `DetectionClass`, `AuditEvent`, `Session` entities
 - linq2db (`LinqToDB.Data.DataConnection`, `LinqToDB.ITable<T>`)

 ## Consumers
- `DbFactory` — creates `AzaionDb` instances inside `Run`/`RunAdmin` methods
+- `DbFactory` — creates `AzaionDb` instances inside `Run`/`RunAdmin`
+- `UserService`, `DetectionClassService`, `RefreshTokenService`, `SessionService`, `MissionTokenService`, `MfaService`, `AuditLog` — all consume the ITables via `IDbFactory.Run`/`RunAdmin` lambdas

 ## Data Models
-Provides access to the `users` table.
+Provides access to four tables: `users`, `detection_classes`, `audit_events`, `sessions`.

 ## Configuration
-Receives `DataOptions` (containing connection string + mapping schema) from `DbFactory`.
+Receives `DataOptions` (containing connection string + mapping schema) from `DbFactory`. The schema instance is shared between read and write `DataOptions` — produced by `AzaionDbShemaHolder.GetSchema()` once and reused.

 ## External Integrations
-PostgreSQL database via Npgsql.
+PostgreSQL via Npgsql.

 ## Security
-None at this level; connection string security is handled by `DbFactory`.
+None at this level. `IDbFactory.Run` selects the read-only connection (`AzaionDb` connection string), `RunAdmin` selects the read/write one (`AzaionDbAdmin`). The grant set on each table determines what each connection can do — see `data_model.md` §Permissions.

 ## Tests
-Indirectly used by `UserServiceTest`.
+Exercised end-to-end via the e2e suite (`e2e/Azaion.E2E/Tests/*`). All cycle-2 services have dedicated test files (`RefreshTokenFlowTests`, `LogoutRevocationTests`, `MissionTokenTests`, `MfaLoginTests`, `LoginRateLimitTests`, `PasswordHashingTests`, `AsymmetricSigningTests`, `CorsHttpsTests`).
@@ -3,6 +3,10 @@
 ## Purpose
 Static holder for the linq2db `MappingSchema` that maps C# entities to PostgreSQL table/column naming conventions and handles custom type conversions.

+> **Cycle 1 (2026-05-13)** — `DetectionClass` mapping added (AZ-513).
+>
+> **Cycle 2 (2026-05-14)** — `AuditEvent` and `Session` mappings added; `User.MfaRecoveryCodes` mapped as `DataType.BinaryJson` (jsonb) to satisfy Npgsql's strict OID matching for jsonb columns (AZ-534).
+
 ## Public Interface

 | Member | Type | Description |
@@ -12,26 +16,27 @@ Static holder for the linq2db `MappingSchema` that maps C# entities to PostgreSQ
 ## Internal Logic
 Static constructor:
 1. Creates a `MappingSchema` with a global callback that converts all column names to snake_case via `StringExtensions.ToSnakeCase`.
-2. Uses `FluentMappingBuilder` to configure the `User` entity:
-   - Table name: `"users"`
-   - `Id`: primary key, `DataType.Guid`
-   - `Role`: stored as text, with custom conversion to/from `RoleEnum` via `Enum.Parse`
-   - `UserConfig`: stored as nullable JSON text, serialized/deserialized via `Newtonsoft.Json`
+2. Uses `FluentMappingBuilder` to configure the entities:
+   - **`User`** — table `"users"`, `Id` PK (Guid), `Role` text with `Enum.Parse` round-trip, `UserConfig` JSON via `Newtonsoft.Json` round-trip, **`MfaRecoveryCodes`** (AZ-534) as `DataType.BinaryJson` so Npgsql sends the jsonb OID instead of text (otherwise inserts fail with "column is of type jsonb but expression is of type text").
+   - **`DetectionClass`** — table `"detection_classes"`, `Id` PK + identity (DB-assigned).
+   - **`AuditEvent`** (AZ-537+534) — table `"audit_events"`, `Id` PK + identity.
+   - **`Session`** (AZ-531+535+533+534) — table `"sessions"`, `Id` PK (Guid). All other columns rely on the snake_case auto-mapping.

 ## Dependencies
- `User`, `RoleEnum` entities
+- `User`, `RoleEnum`, `DetectionClass`, `AuditEvent`, `Session` entities
+- `UserConfig` (for the JSON conversion)
 - `StringExtensions.ToSnakeCase`
 - linq2db `MappingSchema`, `FluentMappingBuilder`
 - `Newtonsoft.Json`

 ## Consumers
- `DbFactory.LoadOptions` — passes `MappingSchema` to `DataOptions.UseMappingSchema()`
+- `DbFactory.LoadOptions` — passes `MappingSchema` to `DataOptions.UseMappingSchema()` for both read and write `DataOptions` (single shared instance).

 ## Data Models
-Defines the ORM mapping for the `users` table.
+Defines the ORM mapping for `users`, `detection_classes`, `audit_events`, `sessions` tables.

 ## Configuration
-None — all mappings are compile-time.
+None — all mappings are compile-time. The `MappingSchema` is built once at first use of the static class and shared across the entire process.

 ## External Integrations
 None directly; mappings are used when queries execute against PostgreSQL.
@@ -40,4 +45,4 @@ None directly; mappings are used when queries execute against PostgreSQL.
 None.

 ## Tests
-None.
+Exercised end-to-end via the e2e suite. Misconfigured jsonb mapping would surface as a `42804` Postgres error (`column is of type jsonb but expression is of type text`) on the first MFA confirm — covered by `e2e/Azaion.E2E/Tests/MfaLoginTests.cs`.
@@ -0,0 +1,73 @@
+# Module: Azaion.Common.Entities.AuditEvent
+
+## Purpose
+Append-only audit row for security-relevant events: login outcomes, lockouts, and the MFA enrollment / login lifecycle. Drives both the per-account sliding-window rate limit (AZ-537) and the human-readable security trail.
+
+> Added in cycle 2 (2026-05-14). Initial event types from AZ-537 (login_failed / login_success / login_lockout); MFA event types added by AZ-534 in the same cycle.
+
+## Public Interface
+
+### AuditEvent
+
+| Property | Type | Description |
+|----------|------|-------------|
+| `Id` | `long` | DB-assigned identity. |
+| `EventType` | `string` | One of `AuditEventTypes`. |
+| `OccurredAt` | `DateTime` | `now()` at insert. |
+| `Email` | `string?` | Normalised lowercase. NULL for system events without a subject. |
+| `Ip` | `string?` | Caller IP from `HttpContext.Connection.RemoteIpAddress`. NULL for background tasks. |
+| `Metadata` | `string?` | Reserved for future structured payload. Not used today. |
+
+### AuditEventTypes (constants)
+
+| Value | When |
+|-------|------|
+| `login_failed` | Wrong password, locked account, or rate-limit reject. |
+| `login_lockout` | Account just hit `MaxAttempts` and was locked. |
+| `login_success` | Password verified, MFA not required. |
+| `mfa_enroll` | `/users/me/mfa/enroll` succeeded. |
+| `mfa_confirm` | `/users/me/mfa/confirm` succeeded; MFA now active. |
+| `mfa_disable` | `/users/me/mfa/disable` succeeded. |
+| `mfa_login_success` | `/login/mfa` succeeded with TOTP. |
+| `mfa_login_failed` | `/login/mfa` rejected (bad TOTP and bad recovery code). |
+| `mfa_recovery_used` | `/login/mfa` succeeded with a recovery code (also burns the code). |
+
+## Internal Logic
+
+None — pure data class. All write/read logic lives in `AuditLog`.
+
+## Dependencies
+
+None.
+
+## Consumers
+
+- `AuditLog` — produces every row; reads via `CountRecentFailedLogins`.
+- `AzaionDb.AuditEvents` — `ITable<AuditEvent>` access.
+- `AzaionDbSchemaHolder` — maps `AuditEvent` to the `audit_events` table.
+
+## Data Models
+
+Maps to PostgreSQL table `audit_events` (defined in `env/db/07_auth_lockout_and_audit.sql`).
+
+Columns: `id (bigserial PK)`, `event_type (varchar(64))`, `occurred_at (timestamp default now())`, `email (varchar(160) NULL)`, `ip (varchar(64) NULL)`, `metadata (text NULL)`.
+
+Index: `audit_events_event_type_email_idx (event_type, email, occurred_at DESC)` — supports the per-account sliding-window failed-login count in O(window-rows).
+
+## Configuration
+
+None.
+
+## External Integrations
+
+None.
+
+## Security
+
+- Append-only by convention — `azaion_admin` only has `INSERT, SELECT` on the table.
+- Stores PII (email, IP); access is gated to `azaion_admin` and `azaion_reader` only. No public endpoint surfaces audit rows.
+- The table backs CMMC AC.L2-3.1.8 ("limit unsuccessful logon attempts") — tampering with it bypasses the rate limit + lockout enforcement.
+
+## Tests
+
+Indirectly tested via `RateLimitLockoutTests`, `MfaEnrollmentTests`, `MfaLoginTests` (assertions on the resulting `audit_events` rows).
@@ -3,6 +3,8 @@
 ## Purpose
 Defines the authorization role hierarchy for the system.

+> **Cycle 2 (2026-05-14) note** — `Service = 60` added by AZ-535 for service-to-service verifier identities (satellite-provider, gps-denied, ui). Each verifier deployment provisions one `Role=Service` user; the role is gated to read `/sessions/revoked` only (via `revocationReaderPolicy`) and is not valid for any user-facing endpoint.
+
 ## Public Interface

 | Enum Value | Int Value | Description |
@@ -10,9 +12,10 @@ Defines the authorization role hierarchy for the system.
 | `None` | 0 | No role assigned |
 | `Operator` | 10 | Annotator access only; can send annotations to queue |
 | `Validator` | 20 | Annotator + dataset explorer; can receive annotations from queue |
-| `CompanionPC` | 30 | Companion PC role |
+| `CompanionPC` | 30 | Companion PC role (UAV / aircraft identities; AZ-533 mission tokens are bound to these via `aircraft_id`) |
 | `Admin` | 40 | Admin role |
-| `ResourceUploader` | 50 | Can upload DLLs and AI models |
+| `ResourceUploader` | 50 | Data-only — `apiUploaderPolicy` was removed in the post-cycle-1 AZ-183 revert. The seed `uploader@azaion.com` user keeps this role for negative-auth tests. |
+| `Service` | 60 | AZ-535 — service-to-service identity for verifiers polling `/sessions/revoked`. NOT valid for any user-facing endpoint. |
 | `ApiAdmin` | 1000 | Full access to all operations |

 ## Internal Logic
@@ -24,11 +27,13 @@ None.
 ## Consumers
 - `User.Role` property type
 - `RegisterUserRequest.Role` property type
- `Program.cs` — authorization policies (`apiAdminPolicy`, `apiUploaderPolicy`)
+- `Program.cs` — authorization policies (`apiAdminPolicy`, `revocationReaderPolicy` cycle 2)
 - `AuthService.CreateToken` — embeds role as claim
- `AzaionDbSchemaHolder` — maps Role to/from text in DB
+- `AzaionDbSchemaHolder` — maps Role to/from text in DB (text enum → `Enum.Parse(typeof(RoleEnum), v)`; the new `Service` value parses through the existing converter without migration)
 - `UserService.GetUsers` — filters by role
 - `UserService.ChangeRole` — updates user role
+- `MissionTokenService.Issue` — validates `aircraft_id` resolves to a `CompanionPC` user
+- `Program.cs` `IssueDualTokens` — fires `RevokeMissionsForAircraft` when the authenticated user has `Role = CompanionPC`

 ## Data Models
 Part of the `User` entity.
@@ -40,7 +45,7 @@ None.
 None.

 ## Security
-Core to the RBAC authorization model. `ApiAdmin` has unrestricted access; `ResourceUploader` can upload resources; other roles have endpoint-level restrictions.
+Core to the RBAC authorization model. `ApiAdmin` has unrestricted access; `Service` is narrowly scoped to the `/sessions/revoked` verifier-poll feed; `ResourceUploader` is data-only after AZ-183 was reverted; other roles have endpoint-level restrictions.

 ## Tests
 None.
@@ -0,0 +1,85 @@
+# Module: Azaion.Common.Entities.Session
+
+## Purpose
+Domain entity representing one issued refresh token (interactive sessions) or one mission token (long-lived UAV sessions). One row per issued token; rotated rows chain via `ParentSessionId` and share a `FamilyId` so reuse-detection and family-wide revocation can key off it.
+
+> Added in cycle 2 (2026-05-14). Initial shape from AZ-531 (interactive refresh-token sessions); extended in the same cycle by AZ-535 (`RevokedByUserId`), AZ-533 (`Class`, `AircraftId`), and AZ-534 (`MfaAuthenticated`).
+
+## Public Interface
+
+### Session
+
+| Property | Type | Description |
+|----------|------|-------------|
+| `Id` | `Guid` | Primary key. |
+| `UserId` | `Guid` | FK to `users.id`. |
+| `RefreshHash` | `string?` | SHA-256 hex of the opaque refresh token. NULL for mission sessions (they have no refresh value). Unique-indexed. |
+| `FamilyId` | `Guid` | All rotations of the same login share this id. For interactive root rows and for mission rows, `FamilyId == Id`. |
+| `IssuedAt` | `DateTime` | Row creation time. |
+| `LastUsedAt` | `DateTime` | Updated on rotation; informational. |
+| `ExpiresAt` | `DateTime` | Sliding (interactive) or absolute (mission) expiry. |
+| `RevokedAt` | `DateTime?` | Set on rotation, reuse-detection, logout, admin revoke, post-flight reconnect. |
+| `RevokedReason` | `string?` | One of `SessionRevokedReasons`. |
+| `ParentSessionId` | `Guid?` | The previous row in the family (set on rotation). |
+| `FamilyStartedAt` | `DateTime` | First-issue time of the family — used for the absolute expiry check. |
+| `RevokedByUserId` | `Guid?` | AZ-535 — audit trail of who revoked the session. NULL for system revocations (rotation, reuse, post-flight). |
+| `Class` | `string` | AZ-533 — `"interactive"` (default) or `"mission"`. |
+| `AircraftId` | `Guid?` | AZ-533 — for mission sessions, the `CompanionPC` user the mission token belongs to. Used by `RevokeMissionsForAircraft`. |
+| `MfaAuthenticated` | `bool` | AZ-534 — pinned at issue; refresh rotation inherits the original AMR strength even if MFA is enabled/disabled mid-session. |
+
+### SessionRevokedReasons (constants)
+
+| Value | When |
+|-------|------|
+| `rotated` | Old row marked as superseded by a successful refresh rotation. |
+| `reuse_detected` | OAuth 2.1 §6.1 — already-rotated refresh re-presented; whole family killed. |
+| `logged_out` | User called `POST /logout`. |
+| `logged_out_all` | User called `POST /logout/all`. |
+| `admin_revoked` | Admin called `POST /sessions/{sid}/revoke`. |
+| `post_flight_reconnect` | Aircraft reconnected; mission auto-revoked. |
+| `family_revoked` | Reserved (manual family-wide revocation; not currently emitted). |
+
+### SessionClasses (constants)
+
+| Value | Meaning |
+|-------|---------|
+| `interactive` | Refresh-backed user session (AZ-531 default). |
+| `mission` | Long-lived no-refresh UAV mission token (AZ-533). |
+
+## Internal Logic
+
+None — pure data class. All session lifecycle logic lives in `RefreshTokenService`, `SessionService`, `MissionTokenService`.
+
+## Dependencies
+
+None.
+
+## Consumers
+
+- `RefreshTokenService` — inserts root/family rows, updates on rotation/reuse-detection
+- `SessionService` — revocation paths and the verifier-poll snapshot
+- `MissionTokenService` — inserts mission-class rows
+- `AzaionDb.Sessions` — `ITable<Session>` access
+- `AzaionDbSchemaHolder` — maps `Session` to the `sessions` table
+
+## Data Models
+
+Maps to PostgreSQL table `sessions` (defined in `env/db/08_sessions.sql`, extended by `09_sessions_logout_and_mission.sql` and `10_users_mfa.sql`).
+
+## Configuration
+
+None.
+
+## External Integrations
+
+None.
+
+## Security
+
+- `refresh_hash` stores SHA-256 of the opaque token; the plaintext is never persisted.
+- The `family_id` partial index `sessions_family_active_idx WHERE revoked_at IS NULL` keeps reuse-detection and `RevokeAllForUser` cheap even as the revoked tail grows.
+- Auto-revoke-on-reconnect (`RevokeMissionsForAircraft`) closes the mission-token "lost UAV" risk when the aircraft phones home again; the partial index `sessions_aircraft_active_idx (aircraft_id, class) WHERE revoked_at IS NULL AND aircraft_id IS NOT NULL` keeps that check O(active mission rows).
+
+## Tests
+
+Indirectly tested via `RefreshTokenTests`, `LogoutTests`, `MissionTokenTests`, and `MfaLoginTests` (which all exercise the entity through the service layer).
@@ -5,18 +5,33 @@ Domain entity representing a system user, plus related value objects `UserConfig

 ## Public Interface

+> **Cycle 2 (2026-05-14) note** — six new properties:
+> - **AZ-537 (CMMC AC.L2-3.1.8)**: `FailedLoginCount` (consecutive failed-login counter) and `LockoutUntil` (active lockout deadline). Both reset on successful login.
+> - **AZ-534 (TOTP 2FA)**: `MfaEnabled`, `MfaSecret` (encrypted via `IDataProtector`), `MfaRecoveryCodes` (JSONB array of `{ hash, used_at }`), `MfaEnrolledAt`, `MfaLastUsedWindow` (RFC 6238 time-step counter — defends in-window replay).
+>
+> `MfaEnabled`, `MfaSecret`, `MfaRecoveryCodes`, and `MfaLastUsedWindow` are `[JsonIgnore]` — they never leave the server in API responses. `PasswordHash` is also `[JsonIgnore]` (this attribute was always there).
+>
+> The `PasswordHash` column now holds an Argon2id PHC string for new + rehashed users (AZ-536); legacy SHA-384 entries still validate and are transparently upgraded on next successful login.
+
 ### User
 | Property | Type | Description |
 |----------|------|-------------|
 | `Id` | `Guid` | Primary key |
 | `Email` | `string` | Unique user email |
-| `PasswordHash` | `string` | SHA-384 hash of plaintext password |
-| `Hardware` | `string?` | Raw hardware fingerprint string (set on first resource access) |
+| `PasswordHash` | `string` | Argon2id PHC string (`$argon2id$…`) for new users; legacy 64-char Base64 SHA-384 still accepted by `Security.VerifyPassword` |
+| `Hardware` | `string?` | TOMBSTONED — kept nullable, not read or written by any code path (AZ-197 removed the hardware-binding feature) |
 | `Role` | `RoleEnum` | Authorization role |
 | `CreatedAt` | `DateTime` | Account creation timestamp |
-| `LastLogin` | `DateTime?` | Last successful resource-check/hardware-check timestamp |
+| `LastLogin` | `DateTime?` | Currently unused — left for forward compatibility |
 | `UserConfig` | `UserConfig?` | JSON-serialized user configuration |
 | `IsEnabled` | `bool` | Account active flag |
+| `FailedLoginCount` | `int` | AZ-537 — consecutive failed-login counter; resets to 0 on success |
+| `LockoutUntil` | `DateTime?` | AZ-537 — active lockout deadline (UTC). `>= now()` blocks login even with correct password |
+| `MfaEnabled` | `bool` | AZ-534 — true after `/users/me/mfa/confirm` succeeds |
+| `MfaSecret` | `string?` | AZ-534 — base32 TOTP secret encrypted at rest via `IDataProtector` (purpose `Azaion.Mfa.Secret.v1`) |
+| `MfaRecoveryCodes` | `string?` | AZ-534 — JSONB array of `{ Hash, UsedAt }` |
+| `MfaEnrolledAt` | `DateTime?` | AZ-534 — set by `Confirm` |
+| `MfaLastUsedWindow` | `long?` | AZ-534 — RFC 6238 time-step counter of the most recently accepted code; rejects in-window replay |

 | Method | Signature | Description |
 |--------|-----------|-------------|
@@ -41,22 +56,30 @@ Domain entity representing a system user, plus related value objects `UserConfig
 - `RoleEnum`

 ## Consumers
- All services (`UserService`, `AuthService`, `ResourcesService`) work with `User`
+- All services (`UserService`, `AuthService`, `ResourcesService`, `MfaService`, `MissionTokenService`) work with `User`
 - `AzaionDb` exposes `ITable<User>`
- `AzaionDbSchemaHolder` maps `User` to the `users` PostgreSQL table
+- `AzaionDbSchemaHolder` maps `User` to the `users` PostgreSQL table; `MfaRecoveryCodes` carries an explicit `DataType.BinaryJson` mapping so Npgsql sends the JSON oid (otherwise inserts fail with "column is of type jsonb but expression is of type text")
 - `SetUserQueueOffsetsRequest` uses `UserQueueOffsets`
+- `Session` rows reference `User` via `UserId` (and via `AircraftId` for mission sessions targeting `RoleEnum.CompanionPC` users)

 ## Data Models
-Maps to PostgreSQL table `users` with columns: `id`, `email`, `password_hash`, `hardware`, `role`, `user_config` (JSON text), `created_at`, `last_login`, `is_enabled`.
+Maps to PostgreSQL table `users` with columns: `id`, `email`, `password_hash`, `hardware`, `role`, `user_config` (JSON text), `created_at`, `last_login`, `is_enabled`, `failed_login_count` (AZ-537), `lockout_until` (AZ-537), `mfa_enabled` (AZ-534), `mfa_secret` (AZ-534), `mfa_recovery_codes` (jsonb, AZ-534), `mfa_enrolled_at` (AZ-534), `mfa_last_used_window` (AZ-534).
+
+Migration files: `env/db/02_structure.sql` (initial), `03_add_timestamp_columns.sql`, `06_users_email_unique.sql` (UNIQUE INDEX on email), `07_auth_lockout_and_audit.sql` (AZ-537 lockout columns + `audit_events` table), `10_users_mfa.sql` (AZ-534 MFA columns).

 ## Configuration
-None.
+None directly. `MfaSecret` encryption depends on the application-level `DataProtection:KeysFolder` setting (Production must point this at a persistent volume).

 ## External Integrations
-None.
+None directly — but `MfaSecret` depends on ASP.NET Core DataProtection for at-rest encryption.

 ## Security
-`PasswordHash` stores SHA-384 hash. `Hardware` stores raw hardware fingerprint (hashed for comparison via `Security.GetHWHash`).
+- `PasswordHash` stores Argon2id PHC strings for new + rehashed users; legacy SHA-384 still accepted (lazy-migrated on next successful login).
+- `MfaSecret` is encrypted at rest via `IDataProtector` (purpose `Azaion.Mfa.Secret.v1`).
+- `MfaRecoveryCodes` are SHA-256-hashed at rest; the plaintext list is shown only in the `/users/me/mfa/enroll` response.
+- `MfaLastUsedWindow` defends against in-window replay of the same TOTP code.
+- `FailedLoginCount` + `LockoutUntil` enforce CMMC AC.L2-3.1.8 (lockout after 10 consecutive failed logins; 15-min default duration).
+- `Hardware` is a tombstone (no application code reads or writes it) per AZ-197.

 ## Tests
-Indirectly tested end-to-end via `e2e/Azaion.E2E/Tests/LoginTests.cs`, `UserManagementTests.cs`, and `DeviceTests.cs`. (The previous in-process `Azaion.Test/UserServiceTest` and `SecurityTest` were both removed by cycle 2 along with the `Azaion.Test` project.)
+Indirectly tested end-to-end via `e2e/Azaion.E2E/Tests/LoginTests.cs`, `UserManagementTests.cs`, `DeviceTests.cs`, `RateLimitLockoutTests.cs`, `MfaEnrollmentTests.cs`, `MfaLoginTests.cs`.
@@ -3,6 +3,8 @@
 ## Purpose
 Request DTO for the `/login` endpoint.

+> **Cycle 2 (2026-05-14) note** — the `/login` response shape changed (AZ-531 added refresh tokens; AZ-534 added the MFA two-step branch), but the **request** body is unchanged. The new response DTOs live in companion files: see `common_requests_login_response.md` (`LoginResponse`, `RefreshTokenRequest`) and `common_requests_mfa_requests.md` (`MfaRequiredResponse`, `MfaLoginRequest`). The `Token` legacy single-token response is preserved via `LoginResponse.Token` for backward compatibility.
+
 ## Public Interface

 | Property | Type | Description |
@@ -17,8 +19,8 @@ None — pure data class. No FluentValidation validator defined for this request
 None.

 ## Consumers
- `Program.cs` `/login` endpoint — receives as request body
- `UserService.ValidateUser` — accepts as parameter
+- `Program.cs` `/login` endpoint — receives as request body; the response is either `LoginResponse` (no MFA) or `MfaRequiredResponse` (MFA enabled)
+- `UserService.ValidateUser` — accepts as parameter; throws lockout/rate-limit/wrong-password/disabled exceptions per AZ-537 + AZ-536

 ## Data Models
 None.
@@ -0,0 +1,53 @@
+# Module: Azaion.Common.Requests.LoginResponse + RefreshTokenRequest
+
+## Purpose
+Response DTO for `/login`, `/login/mfa`, and `/token/refresh` (dual-token shape), plus the request DTO for `/token/refresh`.
+
+> Added in cycle 2 (2026-05-14) by AZ-531 (Epic AZ-529, Refresh-token Flow). The pre-AZ-531 single-token `{ token }` shape is preserved via the `Token` accessor for backward compatibility — pre-AZ-531 clients see the same value via `Token` even though new clients consume `AccessToken` / `RefreshToken`.
+
+## Public Interface
+
+### LoginResponse
+
+| Property | Type | Description |
+|----------|------|-------------|
+| `AccessToken` | `string` | The 15-min ES256 JWT to be sent as `Authorization: Bearer <…>` on subsequent requests. |
+| `AccessExp` | `DateTime` | Absolute expiry of `AccessToken` (UTC). |
+| `RefreshToken` | `string` | Opaque base64url string (43 chars). Send to `/token/refresh` to rotate. NEVER decode — it is not a JWT. |
+| `RefreshExp` | `DateTime` | Sliding expiry of the refresh token (UTC). |
+| `Token` (read-only) | `string` | Backward-compat accessor returning `AccessToken`. Pre-AZ-531 clients that read `Token` keep working. |
+
+### RefreshTokenRequest
+
+| Property | Type | Description |
+|----------|------|-------------|
+| `RefreshToken` | `string` | The opaque token returned in the previous `LoginResponse.RefreshToken` (or in the previous successful `/token/refresh` response). |
+
+## Internal Logic
+None — pure data classes. The `Token` getter is a read-only alias.
+
+## Dependencies
+None.
+
+## Consumers
+- `Program.cs` `/login` — returns `LoginResponse` (when MFA is not required) via the shared `IssueDualTokens` helper.
+- `Program.cs` `/login/mfa` — returns `LoginResponse` via `IssueDualTokens` after second-factor success.
+- `Program.cs` `/token/refresh` — accepts `RefreshTokenRequest`, returns `LoginResponse`.
+- `RefreshTokenService.IssueForNewLogin` / `Rotate` — supplies the values that populate `LoginResponse`.
+
+## Data Models
+None.
+
+## Configuration
+None.
+
+## External Integrations
+None.
+
+## Security
+- `RefreshToken` is high-entropy (256 bits) and opaque. It is never logged and only ever returned in this response shape (HTTPS is mandatory in Production — see AZ-538 HSTS / HTTPS-redirect).
+- `AccessToken` is a JWT carrying `sid`, `jti`, `amr`, role and email claims. Validation is configured in `Program.cs` (`ValidateIssuer`, `ValidateAudience`, `ValidateLifetime`, `ValidateIssuerSigningKey`, `ValidAlgorithms = [ES256]`).
+- Backward-compat note — the `Token` accessor exists so pre-AZ-531 UI builds keep working during the transition. New clients should use `AccessToken` so they can also pick up `AccessExp` for proactive refresh scheduling.
+
+## Tests
+- `e2e/Azaion.E2E/Tests/RefreshTokenTests.cs` — assertions on the shape (AC-1) and on rotation behaviour (AC-2..AC-5).
@@ -0,0 +1,83 @@
+# Module: Azaion.Common.Requests.MfaRequests
+
+## Purpose
+Request and response DTOs for the MFA enrollment / login surface introduced in cycle 2 by AZ-534 (Epic AZ-529, TOTP-based 2FA at credential login). All DTOs live in a single `MfaRequests.cs` file.
+
+## Public Interface
+
+### MfaEnrollRequest
+
+| Property | Type | Description |
+|----------|------|-------------|
+| `Password` | `string` | Re-auth required for enrollment (defends a stolen access token from silently flipping MFA on). |
+
+### MfaEnrollResponse
+
+| Property | Type | Description |
+|----------|------|-------------|
+| `Secret` | `string` | 32-char base32 TOTP shared secret. Shown once. |
+| `OtpAuthUrl` | `string` | Standard `otpauth://` URL the authenticator app consumes. |
+| `QrPngBase64` | `string` | PNG encoding of `OtpAuthUrl` (base64). UI inlines as `data:image/png;base64,…`. |
+| `RecoveryCodes` | `string[]` | 10 single-use base32 codes (each ≥12 chars). Stored hashed in `users.mfa_recovery_codes`; the plaintext list is unrecoverable after this response. |
+
+### MfaConfirmRequest
+
+| Property | Type | Description |
+|----------|------|-------------|
+| `Code` | `string` | TOTP code that validates the enrolled secret. On success `users.mfa_enabled` flips to true. |
+
+### MfaDisableRequest
+
+| Property | Type | Description |
+|----------|------|-------------|
+| `Password` | `string` | Re-auth (same defence as enroll). |
+| `Code` | `string` | A valid TOTP code (recovery codes are NOT accepted here — disable should be deliberate). |
+
+### MfaRequiredResponse
+
+Returned by `POST /login` when the user has MFA enabled instead of `LoginResponse`.
+
+| Property | Type | Description |
+|----------|------|-------------|
+| `MfaRequired` | `bool` | Always `true`. Lets dual-shape clients branch on a single field. |
+| `MfaToken` | `string` | Short-lived (5 min) ES256 JWT with audience `azaion-mfa-step2`. Carry to `/login/mfa`. |
+| `ExpiresIn` | `int` | Step-1 token TTL in seconds (300). |
+
+### MfaLoginRequest
+
+| Property | Type | Description |
+|----------|------|-------------|
+| `MfaToken` | `string` | The step-1 token from `MfaRequiredResponse`. |
+| `Code` | `string` | A valid TOTP code OR a single-use recovery code. |
+
+## Internal Logic
+None — pure data classes.
+
+## Dependencies
+None.
+
+## Consumers
+- `Program.cs` `/users/me/mfa/enroll` — `MfaEnrollRequest` → `MfaEnrollResponse`.
+- `Program.cs` `/users/me/mfa/confirm` — `MfaConfirmRequest`.
+- `Program.cs` `/users/me/mfa/disable` — `MfaDisableRequest`.
+- `Program.cs` `/login` — returns `MfaRequiredResponse` when `user.MfaEnabled`.
+- `Program.cs` `/login/mfa` — `MfaLoginRequest` → `LoginResponse`.
+- `MfaService` — consumes every request type and produces the responses.
+
+## Data Models
+None directly.
+
+## Configuration
+None.
+
+## External Integrations
+None — but `MfaToken` validation depends on `IJwtSigningKeyProvider` (ES256 keys) and `JwtConfig.Issuer`.
+
+## Security
+- `Password` fields carry plaintext credentials; HTTPS is mandatory in Production (AZ-538 HSTS / HTTPS-redirect).
+- `Secret` and `RecoveryCodes` are returned ONCE in `MfaEnrollResponse` — the client must show them immediately and never send them back.
+- `MfaToken` is narrowly-scoped (audience `azaion-mfa-step2`) so it cannot be used against any non-MFA endpoint even if leaked.
+
+## Tests
+- `e2e/Azaion.E2E/Tests/MfaEnrollmentTests.cs` — AC-1 (enroll shape), AC-2 (confirm), AC-5 (disable), AC-6 (encrypted at rest).
+- `e2e/Azaion.E2E/Tests/MfaLoginTests.cs` — AC-3 (two-step + AMR claim), AC-4 (recovery code single-use).
@@ -0,0 +1,59 @@
+# Module: Azaion.Common.Requests.MissionSessionRequest + ValidRegion + MissionSessionResponse
+
+## Purpose
+Request / response DTOs for `POST /sessions/mission` — pilot asks admin to mint a long-lived no-refresh access token for a single UAV flight.
+
+> Added in cycle 2 (2026-05-14) by AZ-533 (Epic AZ-529, Mission-token issuance for disconnected UAV operations).
+
+## Public Interface
+
+### MissionSessionRequest
+
+| Property | Type | Required | Description |
+|----------|------|----------|-------------|
+| `MissionId` | `string` | Yes | Must match `^M-\d{4}-\d{2}-\d{2}-\d{3}$` (validated server-side; HTTP 400 with `InvalidMissionRequest` on miss). |
+| `AircraftId` | `Guid` | Yes | The user id of the `CompanionPC` user representing the aircraft. Must exist; otherwise HTTP 400 with `AircraftNotFound`. |
+| `PlannedDurationH` | `double` | Yes | ∈ `[0.1, 12.0]`. Outside range → 400 `InvalidMissionRequest`. The minted token's `exp` is `now + PlannedDurationH + 1.0 h` (the buffer covers post-flight reconnect grace). |
+| `RequestedScope` | `IList<string>?` | No | Optional permission strings stamped as multi-valued `permissions` claim. |
+| `ValidRegion` | `ValidRegion?` | No | Optional bbox stamped as JSON-typed `valid_region` claim; informational until `satellite-provider` enforces it. |
+
+### ValidRegion
+
+| Property | Type |
+|----------|------|
+| `MinLat` / `MaxLat` / `MinLon` / `MaxLon` | `double` |
+
+### MissionSessionResponse
+
+| Property | Type | Description |
+|----------|------|-------------|
+| `AccessToken` | `string` | The ES256 JWT bound to the mission. Audience `satellite-provider`. |
+| `AccessExp` | `DateTime` | Token expiry (UTC). |
+| `TokenClass` | `string` | Always `"mission"`. |
+| `SessionId` | `Guid` | The `sessions.id` row backing this token; verifiers see this in the `sid` claim. |
+
+## Internal Logic
+None — pure data classes. Validation runs in `MissionTokenService.Validate`; the regex is compiled-once per process.
+
+## Dependencies
+- `System.ComponentModel.DataAnnotations.Required` — surfaces 400 from minimal-API model binding when `MissionId` / `AircraftId` / `PlannedDurationH` are missing or unset.
+
+## Consumers
+- `Program.cs` `/sessions/mission` — receives `MissionSessionRequest`, returns `MissionSessionResponse`.
+- `MissionTokenService.Issue` — accepts `MissionSessionRequest`, returns `MissionSessionResponse`.
+
+## Data Models
+None directly — `MissionTokenService` translates these DTOs into a `Session` row + JWT claims.
+
+## Configuration
+None.
+
+## External Integrations
+None directly. The minted token is consumed by the `satellite-provider` workspace; cross-workspace ticket coordinates verifier-side enforcement of the `mission_id` / `aircraft_id` / `valid_region` claims.
+
+## Security
+- The `MissionId` regex defends against injection of arbitrary text into a claim that downstream verifiers may use for log correlation or ABAC decisions.
+- The 12-hour upper bound on `PlannedDurationH` is a hard cap — any future expansion needs a deliberate config change with a security-review trigger because it directly extends the leak-window of any one mission token.
+
+## Tests
+- `e2e/Azaion.E2E/Tests/MissionTokenTests.cs` — AC-1..AC-5 (lifetime, cap, claims, auto-revoke, auth required).
@@ -0,0 +1,60 @@
+# Module: Azaion.Services.AuditLog
+
+## Purpose
+Append-only audit trail for security-relevant events (login attempts, lockouts, MFA lifecycle). Also exposes the per-account sliding-window failed-login count consumed by `UserService.ValidateUser`'s rate limit.
+
+> Added in cycle 2 (2026-05-14). Initially shipped with AZ-537 (login lockout + per-account rate-limit feed); MFA event types added by AZ-534 in the same cycle.
+
+## Public Interface
+
+### IAuditLog
+
+| Method | Signature | Description |
+|--------|-----------|-------------|
+| `RecordLoginFailed` | `Task RecordLoginFailed(string email, CancellationToken ct = default)` | Inserts `audit_events` row with `event_type='login_failed'`. |
+| `RecordLoginLockout` | `Task RecordLoginLockout(string email, CancellationToken ct = default)` | Inserts `event_type='login_lockout'` (AZ-537 AC-6). |
+| `RecordLoginSuccess` | `Task RecordLoginSuccess(string email, CancellationToken ct = default)` | Inserts `event_type='login_success'`. |
+| `RecordMfaEnroll` / `RecordMfaConfirm` / `RecordMfaDisable` | `Task ...(string email, CancellationToken ct = default)` | MFA enrollment lifecycle. |
+| `RecordMfaLoginSuccess` / `RecordMfaLoginFailed` / `RecordMfaRecoveryUsed` | `Task ...(string email, CancellationToken ct = default)` | MFA login outcomes. |
+| `CountRecentFailedLogins` | `Task<int> CountRecentFailedLogins(string email, int windowSeconds, CancellationToken ct = default)` | Number of `login_failed` rows for the email within the last `windowSeconds`. Drives the per-account sliding-window rate limit (AZ-537 AC-2). |
+
+## Internal Logic
+
+- **Email normalisation** — every insert and read lowercases the email (`ToLowerInvariant`) so case-variant addresses can't bypass the rate limit.
+- **IP capture** — pulls `HttpContext.Connection.RemoteIpAddress` via `IHttpContextAccessor`. Null when there is no current request (background task). Null IPs are persisted as null, not omitted.
+- **Insert path** uses `dbFactory.RunAdmin` (write privilege required); count uses `dbFactory.Run` (read-only).
+- **Backing table** — `public.audit_events`, defined by `env/db/07_auth_lockout_and_audit.sql`. Supporting index `audit_events_event_type_email_idx (event_type, email, occurred_at DESC)` makes the per-account sliding-window count O(window-rows).
+
+## Dependencies
+
+- `IDbFactory` — read + admin connections
+- `IHttpContextAccessor` — for the request IP
+- `AuditEvent` entity, `AuditEventTypes` constants
+
+## Consumers
+
+- `UserService.ValidateUser` — calls `CountRecentFailedLogins` (per-account rate limit), `RecordLoginFailed`, `RecordLoginSuccess`, `RecordLoginLockout`.
+- `MfaService` — calls every `RecordMfa*` method along the enroll/confirm/disable/login paths.
+
+## Data Models
+
+Operates on the `AuditEvent` entity via `AzaionDb.AuditEvents` table.
+
+## Configuration
+
+None directly. The window/threshold constants live on `AuthConfig.RateLimit` and `AuthConfig.Lockout`, consumed by the caller (`UserService.ValidateUser`).
+
+## External Integrations
+
+PostgreSQL via `IDbFactory`.
+
+## Security
+
+- Append-only by convention — no UPDATE/DELETE in code, and `azaion_admin` only has `INSERT, SELECT` on the table.
+- The IP and email are PII; access to the table is gated to `azaion_admin` (insert + read) and `azaion_reader` (read-only). No public endpoint surfaces audit rows directly.
+- The per-account sliding-window count is the foundation of CMMC AC.L2-3.1.8 enforcement; tampering with `audit_events` bypasses the rate limit.
+
+## Tests
+
+- `e2e/Azaion.E2E/Tests/RateLimitLockoutTests.cs` — exercises `RecordLoginFailed` + `CountRecentFailedLogins` end-to-end via the lockout/rate-limit ACs.
+- `e2e/Azaion.E2E/Tests/MfaEnrollmentTests.cs` and `MfaLoginTests.cs` — assert the corresponding MFA `audit_events` rows after each lifecycle event.
@@ -1,48 +1,81 @@
 # Module: Azaion.Services.AuthService

 ## Purpose
-JWT token creation and current-user resolution from HTTP context claims.
+Mints short-lived (15 min) ES256 access tokens and resolves the current user from HTTP context claims.
+
+> **Cycle 2 (2026-05-14) note (AZ-531 / AZ-532 / AZ-534)** — `CreateToken` was completely reshaped:
+> - Signing switched from HMAC-HS256 (`JwtConfig.Secret`) to ES256 via `IJwtSigningKeyProvider` (AZ-532).
+> - Lifetime is now `JwtConfig.AccessTokenLifetimeMinutes` (default 15) instead of the old `TokenLifetimeHours` (default 4).
+> - Tokens stamp two new claims required by the refresh / logout flow: `sid` (session id) and `jti` (per-token unique id).
+> - Tokens stamp the RFC 8176 `amr` claim (multi-valued; defaults to `["pwd"]`, becomes `["pwd","mfa"]` after `/login/mfa`, with `"recovery"` appended when a recovery code was used).
+> - Returns an `AccessToken` record (`Jwt` + `ExpiresAt`) so callers can populate `LoginResponse.AccessExp` directly.

 ## Public Interface

 ### IAuthService
 | Method | Signature | Description |
 |--------|-----------|-------------|
-| `GetCurrentUser` | `Task<User?> GetCurrentUser()` | Extracts email from JWT claims, returns full User entity |
-| `CreateToken` | `string CreateToken(User user)` | Generates a signed JWT token for the given user |
+| `GetCurrentUser` | `Task<User?> GetCurrentUser()` | Reads `ClaimTypes.Name` from `HttpContext.User`, delegates to `IUserService.GetByEmail`. |
+| `CreateToken` | `AccessToken CreateToken(User user, Guid sessionId, Guid jti, IEnumerable<string>? amr = null)` | Mints a 15-min ES256 access token bound to `sessionId`/`jti`, with the supplied `amr` values. |
+
+### `record AccessToken(string Jwt, DateTime ExpiresAt)`
+
+The token string + its absolute expiry (UTC). `Program.cs` packs this into `LoginResponse.AccessToken` / `LoginResponse.AccessExp`.

 ## Internal Logic
- **GetCurrentUser**: reads `ClaimTypes.Name` from `HttpContext.User.Claims`, then delegates to `IUserService.GetByEmail`.
- **CreateToken**: builds a `SecurityTokenDescriptor` with claims (NameIdentifier = user ID, Name = email, Role = role), signs with HMAC-SHA256 using the configured secret, sets expiry from `JwtConfig.TokenLifetimeHours`.

-Private method:
- `GetCurrentUserEmail` — extracts email from claims dictionary.
+- **CreateToken** builds claims:
+  - `ClaimTypes.NameIdentifier` = `user.Id`
+  - `ClaimTypes.Name` = `user.Email`
+  - `ClaimTypes.Role` = `user.Role.ToString()`
+  - `JwtRegisteredClaimNames.Sid` = `sessionId.ToString()`
+  - `JwtRegisteredClaimNames.Jti` = `jti.ToString()`
+  - One `amr` claim per element of the `amr` parameter (defaults to `["pwd"]`).
+- Signs with `SigningCredentials(active.SecurityKey, SecurityAlgorithms.EcdsaSha256)` using the active key from `IJwtSigningKeyProvider`. The `kid` JWT header is auto-stamped because `ECDsaSecurityKey.KeyId` is set per loaded key.
+- Lifetime: `now + JwtConfig.AccessTokenLifetimeMinutes`.
+- **GetCurrentUser**: reads `ClaimTypes.Name` from `HttpContext.User.Claims` and delegates to `IUserService.GetByEmail` (which is cached).

 ## Dependencies
+
 - `IHttpContextAccessor` — for accessing current HTTP context
- `IOptions<JwtConfig>` — JWT configuration
+- `IOptions<JwtConfig>` — `Issuer`, `Audience`, `AccessTokenLifetimeMinutes`
+- `IJwtSigningKeyProvider` (cycle 2 — ES256 active key)
 - `IUserService` — for `GetByEmail` lookup
 - `System.IdentityModel.Tokens.Jwt`
 - `Microsoft.IdentityModel.Tokens`

 ## Consumers
- `Program.cs` `/login` endpoint — calls `CreateToken` after successful validation
- `Program.cs` `/users/current` — calls `GetCurrentUser` (the previously listed `/resources/get`, `/resources/get-installer`, `/resources/check` consumers were removed in cycle 2 / by AZ-197 along with their endpoints)
+
+- `Program.cs` `/login` (after `UserService.ValidateUser`) → calls `CreateToken` via the shared `IssueDualTokens` helper.
+- `Program.cs` `/login/mfa` → calls `CreateToken` with `amr` from `MfaService.VerifyForLogin`.
+- `Program.cs` `/token/refresh` → calls `CreateToken` with `amr` reconstructed from the session's `MfaAuthenticated` flag.
+- `Program.cs` `/users/current` → calls `GetCurrentUser`.
+- `MfaService.IssueMfaStepToken` and `MissionTokenService.MintToken` mint their own tokens directly (separate audiences); they bypass `AuthService.CreateToken` on purpose.

 ## Data Models
 None.

 ## Configuration
-Uses `JwtConfig` (Issuer, Audience, Secret, TokenLifetimeHours).
+
+`JwtConfig`:
+- `Issuer`, `Audience` — claim values
+- `AccessTokenLifetimeMinutes` (default 15) — access TTL
+- `KeysFolder`, `ActiveKid` — signing key selection (consumed via `IJwtSigningKeyProvider`)
+
+The legacy `JwtConfig.Secret` field is **no longer read** — the codebase keeps the property only as a temporary rollback escape hatch and to avoid breaking any environment that still binds it.

 ## External Integrations
-None.
+None directly. Signing key material lives on disk in `JwtConfig.KeysFolder` (default `secrets/jwt-keys/`).

 ## Security
- Token includes user ID, email, and role as claims
- Signed with HMAC-SHA256
- Expiry controlled by `TokenLifetimeHours` config
- Token validation parameters are configured in `Program.cs` (ValidateIssuer, ValidateAudience, ValidateLifetime, ValidateIssuerSigningKey)
+
+- Asymmetric ES256 signing — verifiers hold only the public key set (served at `/.well-known/jwks.json`). A compromised verifier can no longer mint admin tokens.
+- `ValidAlgorithms = [SecurityAlgorithms.EcdsaSha256]` is pinned in `Program.cs` JwtBearer config to defeat the alg-confusion attack (forging a token with `alg=HS256` using the public key as the HMAC secret).
+- Every token now carries `sid` and `jti`. `sid` is the AZ-535 logout / family-revocation key; `jti` reserves the option of a per-access denylist if revocation latency ever needs to drop below the verifier-poll interval.
+- The 15-min access TTL plus refresh-token rotation (AZ-531) constrains the leak-window of a stolen access token to <15 min.

 ## Tests
-None.
+- `e2e/Azaion.E2E/Tests/RefreshTokenTests.cs` (AC-1, AC-2) — verifies `AccessExp ≈ now + 15m` and that rotation produces a fresh access token.
+- `e2e/Azaion.E2E/Tests/JwksTests.cs` (AC-1) — verifies `alg=ES256` and `kid` header on issued tokens.
+- `e2e/Azaion.E2E/Tests/MfaLoginTests.cs` (AC-3) — verifies the `amr` claim ordering across the two-step login.
+- `e2e/Azaion.E2E/Tests/LogoutTests.cs` — exercises the `sid` claim path.
@@ -0,0 +1,75 @@
+# Module: Azaion.Services.JwtSigningKeyProvider
+
+## Purpose
+Loads ES256 JWT signing keys from a directory of `*.pem` files. One key is "active" (used to sign new tokens); the rest stay in the JWKS feed so in-flight tokens minted with older kids still verify during a rotation overlap window.
+
+> Added in cycle 2 (2026-05-14) by AZ-532 (Epic AZ-529, Auth Mechanism Modernization). Replaces the HS256 shared-secret path; `JwtConfig.Secret` is no longer read by the codebase.
+
+## Public Interface
+
+### IJwtSigningKeyProvider
+
+| Member | Type | Description |
+|--------|------|-------------|
+| `Active` | `JwtSigningKey` | The key the codebase uses to sign new tokens. Selected by `JwtConfig.ActiveKid`; falls back to the first key by filename (sorted ordinal) with a startup log warning if no `ActiveKid` is set. |
+| `All` | `IReadOnlyList<JwtSigningKey>` | Every loaded key, ordered by `Kid`. Surfaced through `/.well-known/jwks.json`. |
+
+### JwtSigningKey
+
+| Property | Type | Description |
+|----------|------|-------------|
+| `Kid` | `string` | Filename without `.pem` extension. |
+| `Ecdsa` | `ECDsa` | Underlying ECDSA instance (P-256). |
+| `SecurityKey` | `ECDsaSecurityKey` | Microsoft.IdentityModel wrapper with `KeyId = Kid`. |
+
+## Internal Logic
+
+- **Eager construction** — built at host construction time in `Program.cs` (before DI is finalized) so `JwtBearer` can resolve issuer signing keys via the same instance DI registers as a singleton. Failures are fail-fast at startup, not at first-request.
+- **Discovery** — `Directory.EnumerateFiles(folder, "*.pem")`, sorted ordinal. Empty folder or missing folder throws `InvalidOperationException` with a pointer to `scripts/generate-jwt-key.sh`.
+- **Curve enforcement** — `EnsureP256` rejects any key whose curve OID is not `1.2.840.10045.3.1.7` / `nistP256` / `ECDSA_P256`. ES256 ⇒ P-256; the wrong curve would silently break verifiers expecting ES256.
+- **Disposal** — `IDisposable` releases every loaded `ECDsa` instance.
+
+## Dependencies
+
+- `IOptions<JwtConfig>` — `KeysFolder` and `ActiveKid`
+- `ILogger<JwtSigningKeyProvider>` — fallback warning when `ActiveKid` is unset
+- System.Security.Cryptography (ECDsa, PEM import)
+- Microsoft.IdentityModel.Tokens (ECDsaSecurityKey)
+
+## Consumers
+
+- `Program.cs` — registered as singleton; supplies the `IssuerSigningKeyResolver` for `JwtBearer` and is shared with `AuthService` / `MfaService` / `MissionTokenService` for signing.
+- `AuthService.CreateToken` — uses `Active.SecurityKey` for `SigningCredentials`.
+- `MfaService.IssueMfaStepToken` / `ValidateMfaStepToken` — same.
+- `MissionTokenService.MintToken` — same.
+- `Program.cs` `/.well-known/jwks.json` — exposes `All` as the JWKS feed.
+
+## Data Models
+
+None.
+
+## Configuration
+
+`JwtConfig.KeysFolder` (default `secrets/jwt-keys`) — directory containing one PEM per key.
+`JwtConfig.ActiveKid` — kid of the currently-signing key. If unset, the first key by filename wins (with a startup log warning).
+
+## External Integrations
+
+Filesystem (read-only on `KeysFolder`).
+
+## Security
+
+- Private key material lives only on disk and in process memory. The JWKS endpoint exports public components only (`x`, `y` for EC).
+- Keys are loaded with `chmod 600` set by `scripts/generate-jwt-key.sh` (the generator script chmods after `openssl ecparam`).
+- Curve pinning prevents accidental signing with a non-P-256 key that would silently break ES256 verifiers.
+- Rotation procedure (per AZ-532 spec, also documented in `scripts/generate-jwt-key.sh`):
+  1. Generate a new PEM with `scripts/generate-jwt-key.sh <new-kid>` next to the existing one.
+  2. Restart admin — JWKS now exposes both kids; the OLD kid is still active for signing.
+  3. Wait verifier-cache TTL (`Cache-Control: max-age=3600` = 1 h).
+  4. Set `JwtConfig__ActiveKid=<new-kid>` and restart admin.
+  5. Wait until all old-kid access tokens have expired (TTL = 15 min).
+  6. Delete the old PEM and restart admin — JWKS now lists only the new kid.
+
+## Tests
+
+- `e2e/Azaion.E2E/Tests/JwksTests.cs` — AC-1 (alg=ES256, kid present), AC-2 (JWKS shape + max-age=3600), AC-3 (two-key overlap during rotation), AC-4 (no private fields in JWKS), AC-5 (alg-confusion attack rejected via pinned `ValidAlgorithms`).
@@ -0,0 +1,73 @@
+# Module: Azaion.Services.MfaService
+
+## Purpose
+RFC 6238 TOTP-based 2FA at credential login. Manages enrollment, confirmation, disable, and second-factor verification, and issues the short-lived step-1 JWT carried between `/login` and `/login/mfa`.
+
+> Added in cycle 2 (2026-05-14) by AZ-534 (Epic AZ-529). Per-user opt-in initially; no policy yet enforces MFA by role. AZ-533 mission-token issuance has a TODO to require `amr=["pwd","mfa"]` once MFA adoption is established.
+
+## Public Interface
+
+### IMfaService
+
+| Method | Signature | Description |
+|--------|-----------|-------------|
+| `Enroll` | `Task<MfaEnrollResponse> Enroll(Guid userId, string password, CancellationToken ct = default)` | Generates a TOTP secret + 10 single-use recovery codes, persists the encrypted secret + hashed recovery codes, returns the secret/otpauth-url/QR/recovery codes (ONCE — recovery codes are unrecoverable after this response). Requires fresh password re-auth. `mfa_enabled` stays false until `Confirm`. |
+| `Confirm` | `Task Confirm(Guid userId, string code, CancellationToken ct = default)` | Validates one TOTP code against the enrolled secret; on success sets `mfa_enabled=true`. |
+| `Disable` | `Task Disable(Guid userId, string password, string code, CancellationToken ct = default)` | Removes MFA; requires both password re-auth and a valid TOTP code (no recovery-code substitution here — disable should be deliberate). |
+| `IssueMfaStepToken` | `string IssueMfaStepToken(Guid userId)` | Mints a 5-minute ES256 JWT (audience `azaion-mfa-step2`) returned at `/login` step-1 when the user has MFA enabled. The client carries it back to `/login/mfa`. |
+| `ValidateMfaStepToken` | `Guid ValidateMfaStepToken(string token)` | Decodes a step-1 token, returns the userId. Throws `BusinessException(InvalidMfaToken)` on bad signature, audience mismatch, or expiry. |
+| `VerifyForLogin` | `Task<string[]> VerifyForLogin(Guid userId, string code, CancellationToken ct = default)` | Step-2 verification at login. Returns the AMR array the access token should carry — `["pwd","mfa"]` for TOTP success, `["pwd","mfa","recovery"]` if a recovery code was consumed. Throws `BusinessException(InvalidMfaCode)` on failure. |
+
+## Internal Logic
+
+- **Secret generation**: 20-byte (160-bit) random key per RFC 6238 §3, encoded as 32-char base32. Stored encrypted at rest via `IDataProtector` (purpose `Azaion.Mfa.Secret.v1`).
+- **otpauth URL**: built via `OtpUri` (Otp.NET) with SHA-1 / 6 digits / 30-sec period — RFC 6238 defaults.
+- **QR**: PNG generated via `QRCoder.QRCodeGenerator` (ECCLevel.M), returned as base64. The endpoint hands the raw PNG bytes back; the UI inlines the data URL.
+- **Recovery codes**: 10 codes, each 10 random bytes → 16-char base32. Stored as `{ Hash, UsedAt }` JSON array; hash is SHA-256 hex (high-entropy secret → fast hash is appropriate, same reasoning as the refresh-token store). Single-use enforcement via the `UsedAt` field plus a conditional update on the prior JSON to defend against concurrent-use races.
+- **TOTP verification** uses Otp.NET's `Totp.VerifyTotp` with `VerificationWindow.RfcSpecifiedNetworkDelay` (±1 step). Each successful verification persists the matched time-step counter to `users.mfa_last_used_window`; subsequent codes with `matched_window <= last_used_window` are rejected to prevent in-window replay.
+- **Step-1 token**: ES256 JWT with audience `azaion-mfa-step2` (intentionally distinct from the main `JwtConfig.Audience` so the main JwtBearer middleware rejects it). Lifetime 5 min — matches AZ-534 AC-3.
+- **Disable's raw SQL** — setting `mfa_recovery_codes` (jsonb) back to NULL via the LinqToDB UPDATE expression API sends an untyped NULL literal that Postgres parses as text and rejects (42804). A small parameterized SQL avoids the type-inference dance.
+
+## Dependencies
+
+- `IDbFactory` — admin connection for user updates
+- `IUserService` — user lookup by id
+- `IDataProtectionProvider` — encrypts `mfa_secret` at rest (key storage configured via `DataProtection:KeysFolder`; defaults to per-machine ephemeral)
+- `IJwtSigningKeyProvider` — ES256 signing for the step-1 token
+- `IOptions<JwtConfig>` — issuer for the step-1 token
+- `IAuditLog` — emits `mfa_enroll` / `mfa_confirm` / `mfa_disable` / `mfa_login_success` / `mfa_login_failed` / `mfa_recovery_used`
+- `Security` — password verification (Argon2id) for re-auth on enroll/disable
+- Otp.NET (TOTP), QRCoder (PNG generation)
+
+## Consumers
+
+- `Program.cs` `/users/me/mfa/enroll`, `/users/me/mfa/confirm`, `/users/me/mfa/disable`
+- `Program.cs` `/login` — calls `IssueMfaStepToken` when `user.MfaEnabled`
+- `Program.cs` `/login/mfa` — calls `ValidateMfaStepToken` then `VerifyForLogin`
+
+## Data Models
+
+Operates on the `User` entity (`mfa_enabled`, `mfa_secret`, `mfa_recovery_codes`, `mfa_enrolled_at`, `mfa_last_used_window` columns added by `env/db/10_users_mfa.sql`).
+
+## Configuration
+
+- `JwtConfig.Issuer` — used as the `iss` of the step-1 token.
+- `DataProtection:KeysFolder` (production must set this to a persistent volume so encrypted MFA secrets survive container restarts; without it the per-machine ephemeral key store will lose every MFA secret on first deploy).
+
+## External Integrations
+
+PostgreSQL via `IDbFactory`. ASP.NET Core DataProtection for at-rest encryption.
+
+## Security
+
+- TOTP secret is base32 (32 chars) encrypted at rest with `IDataProtector`. Plaintext only exists in memory during enroll/verify.
+- Recovery codes are SHA-256-hashed in the DB; the plaintext list is shown ONCE in `MfaEnrollResponse` and unrecoverable thereafter.
+- `mfa_last_used_window` defends against in-window replay (a code presented twice within 30 s is rejected the second time).
+- Step-1 JWT carries a narrowed audience (`azaion-mfa-step2`); the main JwtBearer middleware accepts only `JwtConfig.Audience` and rejects this token for any non-MFA endpoint.
+- Re-auth with password is required for enroll and disable; this defends against a stolen access token being used to silently flip MFA state.
+- **Known follow-up F2 (carried forward from Cycle 2 batch 4 review)**: `TryConsumeRecoveryCode` returns `true` even when the conditional update affects 0 rows — concurrent double-spend of the same recovery code is possible (low practical risk, but a real correctness gap).
+
+## Tests
+
+- `e2e/Azaion.E2E/Tests/MfaEnrollmentTests.cs` — AC-1 (enroll shape), AC-2 (confirm), AC-5 (disable), AC-6 (encrypted at rest).
+- `e2e/Azaion.E2E/Tests/MfaLoginTests.cs` — AC-3 (two-step flow + AMR claim), AC-4 (recovery-code single-use).
@@ -0,0 +1,69 @@
+# Module: Azaion.Services.MissionTokenService
+
+## Purpose
+Issues long-lived (≤ 12 h) single-use access tokens for offline UAV missions. Distinct from `AuthService.CreateToken` because:
+- Lifetime is per-mission (`planned_duration_h + 1 h` buffer), not the 15-minute interactive policy.
+- Audience is narrowed to `satellite-provider`, not the broad admin audience.
+- No refresh: a single token covers the entire flight, then dies.
+- Carries mission-specific claims (`mission_id`, `aircraft_id`, `valid_region`, `permissions`).
+
+> Added in cycle 2 (2026-05-14) by AZ-533 (Epic AZ-529). Solves the "10 h offline UAV vs. 15 min interactive access token" tension without weakening interactive-session security.
+
+## Public Interface
+
+### IMissionTokenService
+
+| Method | Signature | Description |
+|--------|-----------|-------------|
+| `Issue` | `Task<MissionSessionResponse> Issue(Guid pilotUserId, MissionSessionRequest request, CancellationToken ct = default)` | Validates the request, persists a `class='mission'` row in `sessions`, mints an ES256 access token bound to that session id, returns the token + expiry + session id. |
+
+## Internal Logic
+
+- **Validation**:
+  - `mission_id` must match `^M-\d{4}-\d{2}-\d{2}-\d{3}$` (compiled regex).
+  - `planned_duration_h` ∈ `[0.1, 12.0]` — anything outside throws `BusinessException(InvalidMissionRequest)` (HTTP 400).
+  - `aircraft_id` must exist in `users` with `Role=CompanionPC`; otherwise `BusinessException(AircraftNotFound)`.
+- **Session row first, then token** — the row is inserted *before* the JWT is minted so revocation lookups can never miss a token already in the wild.
+- **Lifetime** = `planned_duration_h + 1.0` (the 1-hour buffer covers post-flight reconnect grace).
+- **Family handling** — mission sessions are their own family (`family_id = id`); they never rotate.
+- **Token claims**: `sub` = pilotUserId, `sid` = session id, `jti` = unique token id, `mission_id`, `aircraft_id`, `token_class="mission"`, optional `permissions` (multi-valued), optional `valid_region` (JSON-typed claim). Audience pinned to `satellite-provider`.
+- **Auto-revoke on reconnect** is implemented in `Program.cs` via `ISessionService.RevokeMissionsForAircraft`, fired from `/login` and `/token/refresh` whenever the caller is a `CompanionPC` user.
+
+## Dependencies
+
+- `IDbFactory` — admin connection for inserting the mission session row, read connection for the aircraft existence check
+- `IJwtSigningKeyProvider` — ES256 active key
+- `IOptions<JwtConfig>` — issuer
+- `Session` entity, `SessionClasses.Mission` constant
+- `MissionSessionRequest` / `MissionSessionResponse` DTOs
+
+## Consumers
+
+- `Program.cs` `/sessions/mission` (requires interactive auth; per AZ-533 the AC-6 step-up MFA gate is a TODO until org-wide MFA adoption)
+
+## Data Models
+
+Operates on the `Session` entity (`class='mission'`, `aircraft_id` set, `refresh_hash` null).
+
+## Configuration
+
+- `JwtConfig.Issuer` — issuer claim of the minted token.
+- Hard-coded constants:
+  - `MissionAudience = "satellite-provider"` — verifier-side audience gate.
+  - `MaxDurationHours = 12.0`, `MinDurationHours = 0.1`.
+  - `LifetimeBufferHours = 1.0`.
+
+## External Integrations
+
+PostgreSQL via `IDbFactory`. Token consumed by the `satellite-provider` workspace (verifier-side enforcement of `mission_id`/`aircraft_id`/`valid_region` is filed under that workspace).
+
+## Security
+
+- Long-lived tokens are inherently dangerous if leaked. Hardware binding (mTLS / DPoP / `cnf`) is the long-term answer; documented as a known risk in `_docs/05_security/security_report.md`.
+- The narrowed audience (`satellite-provider`) prevents a stolen mission token from being usable against the admin API itself; admin endpoints still require `JwtConfig.Audience`.
+- The `valid_region` bbox is informational until `satellite-provider` enforces it (cross-workspace coordination ticket).
+- Mission tokens are auto-revoked the moment the aircraft reconnects (`/login` or `/token/refresh` from a `CompanionPC` user). Verifiers polling `/sessions/revoked` see the revocation within their poll interval (≤ 30 s).
+
+## Tests
+
+- `e2e/Azaion.E2E/Tests/MissionTokenTests.cs` — AC-1 (correct lifetime + claims), AC-2 (12h cap), AC-3 (scope claims), AC-4 (auto-revoke on reconnect), AC-5 (auth required).
@@ -0,0 +1,63 @@
+# Module: Azaion.Services.RefreshTokenService
+
+## Purpose
+Issues, rotates, and validates opaque refresh tokens for interactive sessions. Implements OAuth 2.1 §6.1 reuse-detection: presenting an already-rotated refresh token kills the entire session family.
+
+> Added in cycle 2 (2026-05-14) by AZ-531 (Epic AZ-529, Auth Mechanism Modernization). Foundation for AZ-535 (logout/revocation) and AZ-534 (MFA — pins `mfa_authenticated` to the session so refresh rotation inherits the original AMR strength).
+
+## Public Interface
+
+### IRefreshTokenService
+
+| Method | Signature | Description |
+|--------|-----------|-------------|
+| `IssueForNewLogin` | `Task<(string OpaqueToken, Session Session)> IssueForNewLogin(Guid userId, bool mfaAuthenticated = false, CancellationToken ct = default)` | Mint a fresh refresh token at login; starts a new session family. The opaque token is returned to the caller; only its SHA-256 hash is persisted. `mfaAuthenticated` is pinned to the session row so rotation preserves AMR strength. |
+| `Rotate` | `Task<(string OpaqueToken, Session Session)> Rotate(string opaqueToken, CancellationToken ct = default)` | Rotate the supplied refresh token. On success returns a new opaque token + the new session row. Throws `BusinessException(InvalidRefreshToken)` on bad/expired/revoked input; on reuse-detection (already-rotated token presented again) the entire session family is revoked first. |
+
+## Internal Logic
+
+- **Token format**: 32 random bytes (256 bits) base64url-encoded → 43-char string (no padding). Persisted as the SHA-256 hex digest in `sessions.refresh_hash`. The opaque value is never logged.
+- **Family semantics**: each `IssueForNewLogin` creates a new family (`family_id == id`). Each `Rotate` inserts a new row in the same family with `parent_session_id` chained to the previous row, then marks the previous row `revoked_reason='rotated'`.
+- **Reuse detection**: if a presented token is found with `revoked_reason='rotated'`, every active row in the same family is set to `revoked_reason='reuse_detected'` (per OAuth 2.1 §6.1) — even the row that succeeded last cycle stops working.
+- **Sliding expiry**: each rotation moves `expires_at` to `now + RefreshSlidingHours` (default 8 h).
+- **Absolute cap**: a family older than `RefreshAbsoluteHours` (default 12 h) since `family_started_at` is rejected even if every individual rotation stayed within the sliding window.
+- **Concurrency**: rotation runs in a `Serializable` transaction so two concurrent refreshes of the same token can't both succeed.
+
+## Dependencies
+
+- `IDbFactory` — admin connection for inserts/updates
+- `IOptions<SessionConfig>` — sliding/absolute window TTLs (defined alongside `JwtConfig` in `Azaion.Common/Configs/JwtConfig.cs`)
+- `Session` entity, `SessionRevokedReasons` constants
+- `BusinessException` / `ExceptionEnum.InvalidRefreshToken`
+- `System.Security.Cryptography.RandomNumberGenerator` + `SHA256`
+
+## Consumers
+
+- `Program.cs` `/login` → calls `IssueForNewLogin` after `UserService.ValidateUser` succeeds
+- `Program.cs` `/login/mfa` → calls `IssueForNewLogin` after MFA second factor
+- `Program.cs` `/token/refresh` → calls `Rotate`
+
+## Data Models
+
+Operates on the `Session` entity via `AzaionDb.Sessions` table.
+
+## Configuration
+
+`SessionConfig` (bound from `appsettings.json` section `SessionConfig`):
+- `RefreshSlidingHours` (default 8)
+- `RefreshAbsoluteHours` (default 12)
+
+## External Integrations
+
+PostgreSQL via `IDbFactory`.
+
+## Security
+
+- Refresh tokens are opaque random strings, never JWTs — verifiers cannot decode or alter them.
+- The plaintext token leaves the server only at issue/rotation; the DB stores only the SHA-256 hash.
+- Reuse-detection is the primary defence against stolen-refresh-token attacks: the legitimate user's next refresh will be rejected and they'll be forced to re-authenticate, but the attacker's token also dies.
+- Rotation is transactional (`Serializable`) so concurrent refresh races cannot leak two valid descendants.
+
+## Tests
+
+- `e2e/Azaion.E2E/Tests/RefreshTokenTests.cs` — covers AC-1 (login dual tokens), AC-2 (rotation invalidates old), AC-3 (reuse kills family), AC-4 (sliding + absolute expiry), AC-5 (opaque, not JWT).
@@ -1,39 +1,79 @@
 # Module: Azaion.Services.Security

 ## Purpose
-Static utility class providing the SHA-384 password hashing helper used by `UserService`.
+Static utility class providing password hashing and verification. As of cycle 2, hashes new passwords with **Argon2id (RFC 9106)** and transparently re-hashes legacy SHA-384 entries on the next successful login.

-> **Cycle 1 (2026-05-13) note** — `GetHWHash` was deleted and `GetApiEncryptionKey` was simplified from `(email, password, hardwareHash)` to `(email, password)` by AZ-197.
+> **Cycle 1 (2026-05-13) note** — `GetHWHash` deleted; `GetApiEncryptionKey` simplified by AZ-197.
 >
-> **Cycle 2 (2026-05-14) note** — `GetApiEncryptionKey`, `EncryptTo`, and `DecryptTo` were all removed along with the encrypted-download endpoint. Only `ToHash` remains; it still backs SHA-384 password hashing in `UserService` (`PasswordHash = request.Password.ToHash()`). The `Azaion.Test/SecurityTest.cs` unit tests went with the removed methods, leaving the `Azaion.Test` project empty (also removed from the solution). See `_docs/06_metrics/retro_2026-05-14.md` once cycle 2's retro lands.
+> **Cycle 2 (2026-05-14) note A** — `GetApiEncryptionKey` / `EncryptTo` / `DecryptTo` removed with the encrypted-download endpoint. The `Azaion.Test` project went with them.
+>
+> **Cycle 2 (2026-05-14) note B (AZ-536)** — `ToHash` was removed and replaced with `HashPassword` + `VerifyPassword`. Hash format is now PHC: `$argon2id$v=19$m=65536,t=3,p=1$<salt-b64>$<hash-b64>`. Legacy SHA-384 hashes (64-char Base64, no `$` prefix) are still accepted for verification and the verify path returns `NeedsRehash=true` so `UserService.ValidateUser` can rewrite them on the success path. Epic AZ-530, CMMC IA.L2-3.5.10.

 ## Public Interface

 | Method | Signature | Description |
 |--------|-----------|-------------|
-| `ToHash` | `static string ToHash(this string str)` | Extension: SHA-384 hash of input, returned as Base64 |
+| `HashPassword` | `static string HashPassword(string plaintext)` | Generates a 16-byte salt, computes Argon2id with the conservative defaults below, returns a PHC string. |
+| `VerifyPassword` | `static VerifyResult VerifyPassword(string plaintext, string stored)` | Detects format by prefix. Argon2id PHC → re-derives + constant-time compare; legacy SHA-384 → re-hashes + constant-time compare. Returns `Valid`, plus `NeedsRehash=true` when (a) the stored hash is legacy SHA-384, or (b) the stored Argon2 parameters are weaker than current defaults. |
+
+### `record VerifyResult(bool Valid, bool NeedsRehash)`
+
+Carries the verification outcome. `NeedsRehash` is the trigger for `UserService.RegisterSuccessfulLogin` to write a fresh Argon2id hash back to the row.

 ## Internal Logic
- `ToHash` uses SHA-384 with UTF-8 encoding, outputting Base64.
+
+**Defaults (RFC 9106 §4 conservative profile)**:
+- Memory: 65536 KiB (64 MiB)
+- Iterations: 3
+- Parallelism: 1
+- Salt: 16 bytes (128 bits) per RFC §3.1 minimum
+- Hash output: 32 bytes (256 bits)
+
+**Format detection**:
+- Argon2id PHC string starts with `$argon2id$`.
+- Legacy SHA-384: exactly 64 base64 characters and does NOT start with `$`.
+- Anything else fails verify with `Valid=false, NeedsRehash=false`.
+
+**PHC encoding** uses base64 *without* padding (PHC convention):
+```
+$argon2id$v=19$m=<KiB>,t=<iters>,p=<lanes>$<salt-b64-nopad>$<hash-b64-nopad>
+```
+
+**Constant-time comparison** uses `CryptographicOperations.FixedTimeEquals` for both formats — addresses AZ-536 AC-5 (no remotely-observable timing leak).

 ## Dependencies
- `System.Security.Cryptography` (SHA384)
- `System.Text.Encoding`
+
+- `Konscious.Security.Cryptography.Argon2` (Argon2id implementation, pure C#)
+- `System.Security.Cryptography.SHA384` (legacy verify path)
+- `System.Security.Cryptography.RandomNumberGenerator` (salt entropy)
+- `System.Security.Cryptography.CryptographicOperations` (constant-time compare)

 ## Consumers
- `Azaion.Services/UserService.cs` — `RegisterUser` (password storage) and `ValidateUser` (login comparison) both call `request.Password.ToHash()`
+
+- `Azaion.Services/UserService.cs`
+  - `RegisterUser` — calls `HashPassword(request.Password)`
+  - `ValidateUser` → `RegisterSuccessfulLogin` — calls `VerifyPassword`; on `NeedsRehash` writes a fresh Argon2id hash back transactionally (conditional on the original hash to avoid clobbering a parallel rehash)
+- `Azaion.Services/MfaService.cs`
+  - `Enroll` and `Disable` — re-auth via `VerifyPassword(password, user.PasswordHash)`

 ## Data Models
 None.

 ## Configuration
-None.
+None directly. The defaults are class-level constants. Bumping them later automatically surfaces `NeedsRehash=true` for any older stored hash, so the upgrade is lazy and transparent.

 ## External Integrations
 None.

 ## Security
- Password hashing uses SHA-384 with no per-user salt and no key stretching. Not resistant to rainbow-table attacks (security audit F-7 — open). Unchanged by cycles 1 and 2.
+
+- Argon2id memory cost (64 MiB) makes GPU bruteforce attacks orders of magnitude slower than the previous SHA-384 path. Each verify costs ~50–200 ms on commodity hardware (intentional latency floor).
+- Legacy SHA-384 hashes are migrated on next successful login (lazy migration). Service accounts that never log in interactively (CompanionPC devices) need an admin-side bulk-reset rotation cycle to upgrade.
+- The verify path is constant-time end-to-end via `FixedTimeEquals` — defends AZ-536 AC-5.
+- The "needs rehash" flag also covers future parameter bumps: raising `Argon2MemoryKib`/`Argon2Iterations` here will make all weaker stored hashes upgrade themselves on the next login.

 ## Tests
-None at the unit-test level after the `Azaion.Test` project was removed in cycle 2. `ToHash` is exercised end-to-end through every login / register e2e test (`e2e/Azaion.E2E/Tests/`).
+
+- `e2e/Azaion.E2E/Tests/PasswordHashingTests.cs` — AC-1 (PHC format), AC-2 (legacy SHA-384 still validates), AC-3 (transparent re-hash), AC-4 (wrong password fails for both formats), AC-5 (constant-time verify).
+- **Known follow-up** (carried from cycle 2 batch 4 review) — `PasswordHashingTests.AC5_Verify_uses_constant_time_comparator_no_obvious_timing_leak` is intermittently flaky under suite-level concurrency; widen the assertion bound or warm Argon2 with a non-test login first.
+- `Azaion.Services` is exercised end-to-end through every login / register / MFA flow in `e2e/Azaion.E2E/Tests/`.
@@ -0,0 +1,65 @@
+# Module: Azaion.Services.SessionService
+
+## Purpose
+Logout / revocation surface and the verifier-poll snapshot. Distinct from `RefreshTokenService` (which rotates and reuse-detects); this service expresses the human / admin / system intent to kill a session and exposes the cross-service denylist feed.
+
+> Added in cycle 2 (2026-05-14) by AZ-535 (Epic AZ-529). The `RevokeMissionsForAircraft` path was added the same day for AZ-533 (mission-token auto-revoke on reconnect).
+
+## Public Interface
+
+### ISessionService
+
+| Method | Signature | Description |
+|--------|-----------|-------------|
+| `RevokeBySid` | `Task<bool> RevokeBySid(Guid sessionId, Guid? byUserId, string reason, CancellationToken ct = default)` | Revoke a single session by id. Returns `true` if the session was already revoked (no-op), `false` if this call performed the revocation. Throws `BusinessException(SessionNotFound)` if no row exists. |
+| `RevokeAllForUser` | `Task<int> RevokeAllForUser(Guid userId, Guid? byUserId, string reason, CancellationToken ct = default)` | Revoke every active session for a user. Returns the number of rows newly revoked. |
+| `RevokeMissionsForAircraft` | `Task<int> RevokeMissionsForAircraft(Guid aircraftId, CancellationToken ct = default)` | AZ-533 — auto-revoke every open mission session for an aircraft. Fired on successful `/login` or `/token/refresh` from a `CompanionPC` user. |
+| `GetRevokedSince` | `Task<IReadOnlyList<RevokedSession>> GetRevokedSince(DateTime since, CancellationToken ct = default)` | Verifier-poll snapshot. Returns sessions revoked after `since` whose `exp` is still in the future (auto-prunes already-expired entries). |
+
+### `record RevokedSession(Guid Sid, DateTime Exp, DateTime RevokedAt, string? Reason)`
+
+Shape returned by `GetRevokedSince`. Field names match the JSON the `/sessions/revoked` endpoint serializes to verifiers.
+
+## Internal Logic
+
+- **Revocation reasons** are constants on `SessionRevokedReasons` (`logged_out`, `logged_out_all`, `admin_revoked`, `post_flight_reconnect`, `rotated`, `reuse_detected`, `family_revoked`).
+- **Idempotency** — `RevokeBySid` reads first, then writes only if `revoked_at IS NULL`. The boolean return signals which side of the race the caller was on.
+- **Mission auto-revoke** uses the partial index `sessions_aircraft_active_idx` (defined in `09_sessions_logout_and_mission.sql`) — O(active mission rows for that aircraft).
+- **Snapshot pruning** — `GetRevokedSince` filters `expires_at > now()` so the response stays bounded even if revocation history grows large; the endpoint additionally clamps `since` to `now - 12 h` to prevent unbounded historical scans.
+
+## Dependencies
+
+- `IDbFactory` — admin connection for updates, read connection for the snapshot
+- `Session` entity, `SessionRevokedReasons`, `SessionClasses` constants
+- `BusinessException` / `ExceptionEnum.SessionNotFound`
+
+## Consumers
+
+- `Program.cs` `/logout` → `RevokeBySid`
+- `Program.cs` `/logout/all` → `RevokeAllForUser`
+- `Program.cs` `/sessions/{sid}/revoke` (admin-only) → `RevokeBySid`
+- `Program.cs` `/sessions/revoked` (verifier-poll, gated by `revocationReaderPolicy`) → `GetRevokedSince`
+- `Program.cs` `/login` and `/token/refresh` (when caller is `RoleEnum.CompanionPC`) → `RevokeMissionsForAircraft`
+
+## Data Models
+
+Operates on the `Session` entity via `AzaionDb.Sessions` table.
+
+## Configuration
+
+None directly. The `/sessions/revoked` endpoint hard-codes the 12-hour `since` floor; review if mission TTL is ever raised above 12 h.
+
+## External Integrations
+
+PostgreSQL via `IDbFactory`.
+
+## Security
+
+- The verifier-poll endpoint is gated by `revocationReaderPolicy` (`Service` or `ApiAdmin` role). Each verifier deployment (satellite-provider, gps-denied, ui) provisions one `Role=Service` user.
+- The `Cache-Control: no-cache` header on `/sessions/revoked` prevents intermediaries from staleing the denylist.
+- The `revoked_by_user_id` column gives an audit trail of "who revoked this session" for admin and user-initiated revocations; system revocations (rotation, reuse, post-flight) leave it null on purpose.
+
+## Tests
+
+- `e2e/Azaion.E2E/Tests/LogoutTests.cs` — covers AC-1 (logout revokes session), AC-2 (logout/all), AC-3 (admin revoke), AC-4 (snapshot recent + prune expired), AC-5 (idempotent logout).
+- `e2e/Azaion.E2E/Tests/MissionTokenTests.cs` — exercises `RevokeMissionsForAircraft` via AC-4 (auto-revoke on reconnect).
@@ -1,69 +1,92 @@
 # Module: Azaion.Services.UserService

 ## Purpose
-Core business logic for user management: registration (web users + provisioned devices), authentication, role management, and account lifecycle.
+Core business logic for user management: registration (web users + provisioned devices), authentication (with rate-limit + lockout enforcement), role management, and account lifecycle.

-> **Cycle 1 (2026-05-13) note** — hardware-binding methods (`UpdateHardware`, `CheckHardwareHash`, private `UpdateLastLoginDate`) and the bound `IUserService` declarations were removed by AZ-197 (admin-side hardware-binding cleanup). Device auto-provisioning (`RegisterDevice`) was added by AZ-196. **Post-cycle-1 (security audit F-3)**: `RegisterDevice` was refactored to delegate the row insert to `RegisterUser`, and `RegisterUser` itself now relies on the new `users_email_uidx` UNIQUE INDEX (`env/db/06_users_email_unique.sql`) — the check-then-insert race is gone; `Npgsql.PostgresException(SqlState=23505)` is translated to `BusinessException(EmailExists)`. See `_docs/03_implementation/batch_05_report.md` and `batch_06_report.md`.
+> **Cycle 1 (2026-05-13) note** — hardware-binding methods removed by AZ-197; device auto-provisioning (`RegisterDevice`) added by AZ-196. Post-cycle-1: `RegisterUser` now relies on the `users_email_uidx` UNIQUE INDEX; `Npgsql.PostgresException(SqlState=23505)` is translated to `BusinessException(EmailExists)`.
+>
+> **Cycle 2 (2026-05-14) note A (AZ-536)** — password hashing switched to Argon2id. `RegisterUser` calls `Security.HashPassword`; `ValidateUser` calls `Security.VerifyPassword`. On a `NeedsRehash=true` outcome the user's row is updated transactionally with a fresh Argon2id hash (conditional on the original `password_hash` to avoid clobbering a parallel rehash from a concurrent login).
+>
+> **Cycle 2 (2026-05-14) note B (AZ-537)** — `ValidateUser` now enforces account lockout (423) and per-account sliding-window rate limit (429-equivalent via `BusinessException(LoginRateLimited)`). The lockout state lives on `users.failed_login_count` / `users.lockout_until`; the rate-limit feed is `audit_events` rows of type `login_failed`. `IAuditLog` and `IOptions<AuthConfig>` are new constructor dependencies.

 ## Public Interface

 ### IUserService
 | Method | Signature | Description |
 |--------|-----------|-------------|
-| `RegisterUser` | `Task RegisterUser(RegisterUserRequest request, CancellationToken ct)` | Creates a new user with hashed password |
-| `RegisterDevice` | `Task<RegisterDeviceResponse> RegisterDevice(CancellationToken ct)` | Creates a new `CompanionPC` user with auto-assigned `azj-NNNN` serial / email and a 32-char hex password (returned plaintext exactly once) |
-| `ValidateUser` | `Task<User> ValidateUser(LoginRequest request, CancellationToken ct)` | Validates email + password, returns user. Throws `NoEmailFound`, `WrongPassword`, or `UserDisabled` |
-| `GetByEmail` | `Task<User?> GetByEmail(string? email, CancellationToken ct)` | Cached user lookup by email |
-| `UpdateQueueOffsets` | `Task UpdateQueueOffsets(string email, UserQueueOffsets offsets, CancellationToken ct)` | Updates user's annotation queue offsets |
-| `GetUsers` | `Task<IEnumerable<User>> GetUsers(string? searchEmail, RoleEnum? searchRole, CancellationToken ct)` | Lists users with optional email/role filters |
-| `ChangeRole` | `Task ChangeRole(string email, RoleEnum newRole, CancellationToken ct)` | Changes a user's role |
-| `SetEnableStatus` | `Task SetEnableStatus(string email, bool isEnabled, CancellationToken ct)` | Enables or disables a user account |
-| `RemoveUser` | `Task RemoveUser(string email, CancellationToken ct)` | Permanently deletes a user |
+| `RegisterUser` | `Task RegisterUser(RegisterUserRequest request, CancellationToken ct)` | Creates a new user with Argon2id-hashed password. Translates `users_email_uidx` 23505 violations to `BusinessException(EmailExists)`. |
+| `RegisterDevice` | `Task<RegisterDeviceResponse> RegisterDevice(CancellationToken ct)` | Creates a new `CompanionPC` user with auto-assigned `azj-NNNN` serial / email and a 32-char hex password (returned plaintext exactly once). |
+| `ValidateUser` | `Task<User> ValidateUser(LoginRequest request, CancellationToken ct)` | Validates email + password; enforces account lockout and per-account rate limit. Returns the user on success (with `failed_login_count` zeroed and any legacy SHA-384 hash transparently upgraded). Throws `NoEmailFound`, `AccountLocked` (with retry-after seconds), `LoginRateLimited` (with retry-after window), `WrongPassword`, or `UserDisabled`. |
+| `GetByEmail` | `Task<User?> GetByEmail(string? email, CancellationToken ct)` | Cached user lookup by email. |
+| `GetById` | `Task<User?> GetById(Guid userId, CancellationToken ct)` | Direct DB lookup by id (used by token-bound flows: refresh, MFA, mission). Not cached. |
+| `UpdateQueueOffsets` | `Task UpdateQueueOffsets(string email, UserQueueOffsets offsets, CancellationToken ct)` | Updates user's annotation queue offsets. |
+| `GetUsers` | `Task<IEnumerable<User>> GetUsers(string? searchEmail, RoleEnum? searchRole, CancellationToken ct)` | Lists users with optional email/role filters. |
+| `ChangeRole` | `Task ChangeRole(string email, RoleEnum newRole, CancellationToken ct)` | Changes a user's role. |
+| `SetEnableStatus` | `Task SetEnableStatus(string email, bool isEnabled, CancellationToken ct)` | Enables or disables a user account. |
+| `RemoveUser` | `Task RemoveUser(string email, CancellationToken ct)` | Permanently deletes a user. |

 ## Internal Logic
- **RegisterUser**: hashes password via `Security.ToHash`, inserts via `RunAdmin`. Catches `Npgsql.PostgresException` with `SqlState == PostgresErrorCodes.UniqueViolation` (23505) on the `users_email_uidx` UNIQUE INDEX and rethrows as `BusinessException(EmailExists)`. The previous check-then-insert pattern was removed (race-prone before the index existed; redundant after).
- **RegisterDevice**: calls private `NextDeviceIdentity` (read-only) to compute the next `azj-NNNN` serial + matching email, generates a 32-char hex password from `RandomNumberGenerator.GetBytes(16)`, then delegates the row insert to `RegisterUser` (so any future change to user-creation policy applies here too). Returns `{Serial, Email, Password}` (plaintext password exposed exactly once at provisioning time). On a serial-allocation race, the second caller's insert hits the UNIQUE INDEX and surfaces `BusinessException(EmailExists)`; the caller can retry.
- **NextDeviceIdentity** (private): queries the most recent `RoleEnum.CompanionPC` user via `dbFactory.Run` (read connection), parses the `azj-NNNN` suffix (chars `[SerialNumberStart, SerialNumberLength)` of the email, constants on the class), increments by 1, returns `(serial, email)`.
- **ValidateUser**: finds user by email, compares password hash. Throws `NoEmailFound`, `WrongPassword`, or `UserDisabled`.
- **GetByEmail**: uses `ICache.GetFromCacheAsync` with key `User.{email}`.
- **UpdateQueueOffsets**: writes via `RunAdmin`, then invalidates the user cache.
- **GetUsers**: uses `WhereIf` for optional filter predicates.
+
+- **RegisterUser**: hashes password via `Security.HashPassword` (Argon2id), inserts via `RunAdmin`. Catches `PostgresException(23505)` on `users_email_uidx` and rethrows as `BusinessException(EmailExists)`.
+- **RegisterDevice**: queries the most recent `RoleEnum.CompanionPC` user via `dbFactory.Run`, parses the `azj-NNNN` suffix, increments by 1, generates a 32-char hex password from `RandomNumberGenerator.GetBytes(16)`, then delegates the row insert to `RegisterUser` (so future user-creation policy changes apply here too).
+- **ValidateUser** (sequence — order matters):
+  1. Lookup by email; missing → `NoEmailFound`.
+  2. **Lockout gate** — if `lockout_until > now()`, throw `AccountLocked` with the remaining seconds as `RetryAfterSeconds`. This precedes the password check (CMMC AC.L2-3.1.8 — even a correct password is rejected during lockout).
+  3. **Per-account rate limit** — `IAuditLog.CountRecentFailedLogins` over `AuthConfig.RateLimit.PerAccountWindowSeconds`; if ≥ `PerAccountPermitLimit`, throw `LoginRateLimited` with the window as `RetryAfterSeconds`.
+  4. **Password verify** via `Security.VerifyPassword`. Failure → `RegisterFailedLogin` (audit row + counter increment + maybe lockout) → throw `WrongPassword` (or `AccountLocked` if the failure crossed the threshold).
+  5. `IsEnabled` check (after verify so wrong-password and disabled-account look identical to attackers from the outside).
+  6. **Success path** — `RegisterSuccessfulLogin`: lazy Argon2id rehash if `NeedsRehash=true` (conditional on the original hash to avoid clobbering a parallel rehash), zero `failed_login_count`, clear `lockout_until`, invalidate cache, write `login_success` audit row.
+- **RegisterFailedLogin**: writes `login_failed` audit row, increments `failed_login_count`. If the new count reaches `Lockout.MaxAttempts`, sets `lockout_until = now() + DurationSeconds`, writes a `login_lockout` audit row, and throws `AccountLocked` immediately so the caller learns the threshold was crossed.
+- **GetByEmail**: cached via `ICache.GetFromCacheAsync` keyed `User.{email}`.
+- **GetById**: not cached (used by token-bound flows where the user id is already authenticated).

 Private constants (device provisioning):
 - `DeviceEmailPrefix = "azj-"`, `DeviceEmailDomain = "@azaion.com"`, `SerialNumberStart = 4`, `SerialNumberLength = 4`, `DevicePasswordBytes = 16`.

 ## Dependencies
+
 - `IDbFactory` (database access)
 - `ICache` (user caching)
- `Security` (hashing — `ToHash`)
+- `IAuditLog` (cycle 2 — audit row writes + per-account rate-limit feed)
+- `IOptions<AuthConfig>` (cycle 2 — `RateLimit.*`, `Lockout.*` thresholds)
+- `Security` (Argon2id hashing — `HashPassword` / `VerifyPassword`)
 - `System.Security.Cryptography.RandomNumberGenerator` (device password entropy)
- `Npgsql` (`PostgresException`, `PostgresErrorCodes.UniqueViolation` — used to translate UNIQUE-INDEX violations to `BusinessException(EmailExists)`)
- `BusinessException` (domain errors)
+- `Npgsql` (`PostgresException`, `PostgresErrorCodes.UniqueViolation`)
+- `BusinessException` / `ExceptionEnum` (`NoEmailFound`, `WrongPassword`, `EmailExists`, `UserDisabled`, `AccountLocked`, `LoginRateLimited`)
 - `QueryableExtensions.WhereIf`
 - `User`, `UserConfig`, `UserQueueOffsets`, `RoleEnum`
 - `RegisterUserRequest`, `LoginRequest`, `RegisterDeviceResponse`

 ## Consumers
- `Program.cs` — `/users/*` endpoints delegate to `IUserService`
- `Program.cs` — `POST /devices` calls `RegisterDevice` (added by AZ-196)
+
+- `Program.cs` `/users/*` endpoints — delegate to `IUserService`
+- `Program.cs` `POST /devices` — calls `RegisterDevice`
+- `Program.cs` `/login` — calls `ValidateUser` then either short-circuits to MFA step-1 or issues dual tokens
+- `Program.cs` `/login/mfa`, `/token/refresh`, `/sessions/mission` — call `GetById` after token-side identity is established
 - `AuthService.GetCurrentUser` — calls `GetByEmail`
+- `MfaService` — calls `GetById` for re-auth in `Enroll` / `Confirm` / `Disable` / `VerifyForLogin`

 ## Data Models
-Operates on `User` entity via `AzaionDb.Users` table. The `User.Hardware` column is left in place (nullable, unused) per AZ-197 — see the entity doc.
+
+Operates on `User` entity via `AzaionDb.Users`. Reads `failed_login_count` / `lockout_until` (AZ-537) and `mfa_enabled` (AZ-534). Writes `password_hash`, `failed_login_count`, `lockout_until` along the lockout/rehash paths. The `User.Hardware` column remains a tombstone (nullable, unused) per AZ-197.

 ## Configuration
-None.
+- `AuthConfig.RateLimit.PerAccountPermitLimit` / `PerAccountWindowSeconds` — sliding-window thresholds.
+- `AuthConfig.Lockout.MaxAttempts` / `DurationSeconds` — consecutive-failure lockout.

 ## External Integrations
 PostgreSQL via `IDbFactory`.

 ## Security
- Passwords hashed with SHA-384 (via `Security.ToHash`) before storage.
- Device passwords are returned plaintext to the caller exactly once at provisioning; the persisted form is the SHA-384 hash. The plaintext is never re-derivable.
+
+- Passwords hashed with Argon2id (post-AZ-536). Legacy SHA-384 entries still validate and are transparently upgraded on next successful login.
+- Device passwords are returned plaintext to the caller exactly once at provisioning; the persisted form is the Argon2id hash. The plaintext is never re-derivable.
+- Lockout precedence (CMMC AC.L2-3.1.8): a locked account returns 423 even for a correct password until `lockout_until` passes.
+- The per-account rate limit is DB-backed (via `audit_events`) so it survives process restarts — distinct from the in-memory per-IP limiter that lives in `Program.cs`.
 - Read operations use the read-only DB connection; writes use the admin connection.

 ## Tests
- `e2e/Azaion.E2E/Tests/DeviceTests.cs` — e2e for AZ-196 device-provisioning ACs
- `e2e/Azaion.E2E/Tests/UserManagementTests.cs` and `LoginTests.cs` — e2e coverage for the rest of the user lifecycle (login, register, role change, enable/disable, delete, queue offsets)
-
-(Unit-test coverage in `Azaion.Test/UserServiceTest.cs` was removed earlier with the AZ-197 hardware-binding cleanup; the `Azaion.Test` project itself was removed from the solution in cycle 2 once its only remaining file — `SecurityTest.cs` — was deleted with the encrypted-download stack.)
+- `e2e/Azaion.E2E/Tests/RateLimitLockoutTests.cs` — AZ-537 ACs (per-IP 429, per-account 429, lockout 423, counter reset, lockout auto-expires, audit_events row on lockout).
+- `e2e/Azaion.E2E/Tests/PasswordHashingTests.cs` — AZ-536 ACs (Argon2id format, legacy verify, transparent re-hash, wrong-password fail, constant-time verify).
+- `e2e/Azaion.E2E/Tests/DeviceTests.cs` — AZ-196 device-provisioning ACs.
+- `e2e/Azaion.E2E/Tests/UserManagementTests.cs` and `LoginTests.cs` — broader user lifecycle coverage.
@@ -0,0 +1,66 @@
+# Documentation Ripple Log — Cycle 2 (Auth Modernization, AZ-531..AZ-538)
+
+> Generated by `document` skill, Task Step 0.5 (Import-Graph Ripple), 2026-05-14.
+> Source: cycle-2 implementation report (`_docs/03_implementation/implementation_report_auth_modernization_cycle2.md`).
+
+## Method
+
+For each source file changed by the cycle, identified C# namespace consumers via `rg "using Azaion\.<namespace>"`. Resolved consumer csproj membership via `module-layout.md`. Folded transitively-affected component / module docs into the refresh set.
+
+## Direct + Ripple-affected docs (already refreshed in this cycle)
+
+| Trigger (changed in cycle 2) | Importing namespaces / files | Doc(s) refreshed | Reason |
+|------------------------------|------------------------------|------------------|--------|
+| `Azaion.Services.Security` (Argon2id rebuild — AZ-536) | `UserService`, `MfaService` | `modules/services_security.md`, `modules/services_user_service.md`, `modules/services_mfa_service.md` | API surface changed (`HashPassword`/`VerifyPassword` replace `ToHash`); both consumers had to be re-read |
+| `Azaion.Services.AuthService` (ES256 — AZ-532) | `Azaion.AdminApi/Program.cs` | `modules/services_auth_service.md`, `modules/admin_api_program.md` | `CreateToken` signature (`sid`, `jti`, `amr`); JWKS publication wired in Program.cs |
+| `Azaion.Services.RefreshTokenService` (new — AZ-531) | `Program.cs` | `modules/services_refresh_token_service.md` (new), `modules/admin_api_program.md` | New endpoints `/login`, `/login/mfa`, `/token/refresh` consume it |
+| `Azaion.Services.SessionService` (new — AZ-535) | `Program.cs`, `MissionTokenService`, `UserService.SetEnableStatus` | `modules/services_session_service.md` (new), `modules/admin_api_program.md`, `modules/services_user_service.md`, `modules/services_mission_token_service.md` | `RevokeMissionsForAircraft` called from login/refresh; `RevokeAllForUser` called when user disabled |
+| `Azaion.Services.MfaService` (new — AZ-534) | `Program.cs` | `modules/services_mfa_service.md` (new), `modules/admin_api_program.md` | New endpoints `/users/me/mfa/{enroll,confirm,disable}` + step-1 token in login |
+| `Azaion.Services.MissionTokenService` (new — AZ-533) | `Program.cs` | `modules/services_mission_token_service.md` (new), `modules/admin_api_program.md` | `/sessions/mission` |
+| `Azaion.Services.JwtSigningKeyProvider` (new — AZ-532) | `Program.cs`, `AuthService`, `MfaService` | `modules/services_jwt_signing_key_provider.md` (new), `modules/admin_api_program.md`, `modules/services_auth_service.md`, `modules/services_mfa_service.md` | Eager-built singleton; both JwtBearer `IssuerSigningKeyResolver` and AuthService consume it |
+| `Azaion.Services.AuditLog` (new — AZ-537+534) | `UserService`, `MfaService`, `Program.cs` (DI only) | `modules/services_audit_log.md` (new), `modules/services_user_service.md`, `modules/services_mfa_service.md` | Per-account rate-limit + lifecycle audit |
+| `Azaion.Common.Entities.User` (extended — AZ-537+534) | `UserService`, `MfaService`, `RefreshTokenService` (UserId), `SessionService`, `AuthService` | `modules/common_entities_user.md`, all services above | New columns drive new application logic |
+| `Azaion.Common.Entities.Session` (new — AZ-531+535+533+534) | `RefreshTokenService`, `SessionService`, `MissionTokenService` | `modules/common_entities_session.md` (new); already-listed services | Direct ORM consumer |
+| `Azaion.Common.Entities.AuditEvent` (new — AZ-537+534) | `AuditLog`, `UserService` | `modules/common_entities_audit_event.md` (new) | Direct ORM consumer |
+| `Azaion.Common.Entities.RoleEnum` (extended — `Service` — AZ-535) | `Program.cs` (`revocationReaderPolicy`), `UserService` | `modules/common_entities_role_enum.md`, `modules/admin_api_program.md` | Authorization policy gate |
+| `Azaion.Common.Configs.JwtConfig` (rebuilt — AZ-532) | `Program.cs`, `AuthService`, `MfaService`, `JwtSigningKeyProvider` | `modules/common_configs_jwt_config.md`, downstream services already covered | All ES256-related config |
+| `Azaion.Common.Configs.AuthConfig` (new — AZ-536+537) | `Program.cs`, `UserService`, `Security` | `modules/common_configs_auth_config.md` (new), downstream covered | Argon2id parameters + rate limit + lockout |
+| `Azaion.Common.Configs.SessionConfig` (new — AZ-531) | `Program.cs`, `RefreshTokenService` | folded into `modules/common_configs_jwt_config.md` (renamed JwtConfig + SessionConfig), downstream covered | Refresh sliding + absolute lifetimes |
+| `Azaion.Common.Requests.LoginResponse` / `RefreshTokenRequest` (new — AZ-531) | `Program.cs` | `modules/common_requests_login_response.md` (new), `modules/admin_api_program.md`, `modules/common_requests_login_request.md` (cross-ref note) | New response shape; backward-compat `Token` getter |
+| `Azaion.Common.Requests.MissionSessionRequest` / `MissionSessionResponse` (new — AZ-533) | `Program.cs`, `MissionTokenService` | `modules/common_requests_mission_session_request.md` (new) | New endpoint payload |
+| `Azaion.Common.Requests.MfaRequests` (new — AZ-534) | `Program.cs`, `MfaService` | `modules/common_requests_mfa_requests.md` (new) | Five DTOs grouped in one file |
+| `Azaion.Common.BusinessException` / `ExceptionEnum` (extended — AZ-531+533+534+535+537) | All services + `BusinessExceptionHandler` | `modules/common_business_exception.md`, `modules/admin_api_program.md` (handler section) | New error codes + `Retry-After` header support |
+| `Azaion.Common.Database.AzaionDb` / `AzaionDbShemaHolder` (extended — Sessions + AuditEvents + jsonb mappings) | all services using them | covered transitively via component 01 Data Layer | New ITables; new mappings |
+
+## Component-level rollup
+
+| Component | Refreshed? | Why |
+|-----------|------------|-----|
+| 01 Data Layer | yes | `Session`, `AuditEvent`, extended `User`/`RoleEnum`, new `AuthConfig`/`SessionConfig`, rebuilt `JwtConfig`, new ITables, new indexes |
+| 02 User Management | yes (within `services_user_service.md`) | Argon2id + lockout + rate-limit + audit |
+| 03 Auth & Security | yes | Major rebuild — full rewrite of `components/03_auth_and_security/description.md` |
+| 04 Resource Management | no | Cycle 2 auth-modernization did not touch resource code |
+| 04b Detection Classes | no | Same |
+| 05 Admin API | yes | Major endpoint surface expansion + middleware pipeline rewrite |
+
+## System-level docs refreshed
+
+- `system-flows.md` — F1 rewritten; F11–F17 added; F2/F7/F9 minor edits (Argon2id, session-revoke-on-disable)
+- `data_model.md` — full rewrite to cover sessions / audit_events / new user columns / migrations / permissions
+- `architecture.md` — section 1 rewritten, sections 2–7 updated, ADRs 6–9 added
+- `module-layout.md` — sub-component table refreshed for cycle 2 services
+- `diagrams/flows/flow_login.md` — full rewrite for the dual-token + MFA model
+
+## Tests (out-of-process)
+
+15 new e2e test files under `e2e/Azaion.E2E/Tests/` consume `Azaion.*` namespaces but are out-of-process HTTP tests; they do not have their own module docs by design (per `module-layout.md` §1). They are referenced from each module's "Tests" section.
+
+## Heuristic / parse-failure notes
+
+None. The C# `using` graph was directly resolvable for every changed namespace.
+
+## Out of scope
+
+- `_docs/00_problem/*` — no AC / input-parameter changes from cycle 2 that aren't already captured in the per-task specs
+- `_docs/04_deploy/*` — deployment ripple (ES256 PEM volume, DataProtection volume, HSTS/HTTPS rollout) is owned by the *deploy* skill (Step 14 of the autodev existing-code flow), not the *document* skill
+- `_docs/05_security/*` — security report ripple is owned by the *security* skill
@@ -1,45 +1,65 @@
 # Azaion Admin API — System Flows

-> **Cycle 1 (2026-05-13) note** — F4 (Hardware Check) was deleted by AZ-197; F3 no longer depends on hardware. Two new flows were added: F8 Detection Classes CRUD (AZ-513), F9 Device Auto-Provisioning (AZ-196). F10 OTA Update Check & Publish (AZ-183) was reverted later the same day after the security audit (finding F-1) — the OTA delivery model itself was deemed obsolete; see `_docs/05_security/security_report.md` for context. F3's narrative was updated to drop the hardware-check step.
+> **Cycle 1 (2026-05-13) note** — F4 (Hardware Check) was deleted by AZ-197; F8 Detection Classes (AZ-513), F9 Device Auto-Provisioning (AZ-196) added; F10 OTA reverted after security audit F-1.
 >
-> **Cycle 2 (2026-05-14) note** — F3 (Encrypted Resource Download) and F6 (Installer Download) were removed entirely as obsolete. The encrypted-download support stack (`Security.GetApiEncryptionKey`, `EncryptTo`, `DecryptTo`, `ResourcesService.GetEncryptedResource`, `ResourcesService.GetInstaller`, `GetResourceRequest`, `WrongResourceName` (50)) and the installer config (`SuiteInstallerFolder`, `SuiteStageInstallerFolder`) all went with them. See `_docs/02_document/architecture.md` ADR-003 (retired).
+> **Cycle 2 — early (2026-05-14)** — F3 (Encrypted Resource Download) and F6 (Installer Download) removed entirely as obsolete. ADR-003 retired.
+>
+> **Cycle 2 — Auth Modernization (2026-05-14)** — F1 was rebuilt around the new dual-token + MFA model (AZ-531/532/534/536/537). Six new flows were added: F11 Refresh Token Rotation (AZ-531), F12 Logout / Revocation (AZ-535), F13 Mission Token Issuance (AZ-533), F14 MFA Enrollment & Confirmation (AZ-534), F15 Verifier Revocation Snapshot (AZ-535), F16 Account Lockout & Per-IP Rate Limit (AZ-537). The legacy single-token narrative is no longer accurate.

 ## Flow Inventory

 | # | Flow Name | Trigger | Primary Components | Criticality |
 |---|-----------|---------|-------------------|-------------|
-| F1 | User Login | POST /login | Admin API, User Mgmt, Auth & Security | High |
-| F2 | User Registration | POST /users | Admin API, User Mgmt | High |
-| ~~F3~~ | ~~Encrypted Resource Download~~ | ~~POST /resources/get~~ | — | **REMOVED — cycle 2 (obsolete)** |
-| ~~F4~~ | ~~Hardware Check~~ | ~~POST /resources/check~~ | — | **REMOVED — AZ-197** |
-| F5 | Resource Upload | POST /resources | Admin API, Resource Mgmt | Medium |
-| ~~F6~~ | ~~Installer Download~~ | ~~GET /resources/get-installer~~ | — | **REMOVED — cycle 2 (obsolete)** |
-| F7 | User Management (CRUD) | Various /users/* | Admin API, User Mgmt | Medium |
-| F8 | Detection Classes CRUD *(AZ-513)* | POST/PATCH/DELETE /classes | Admin API, DetectionClassService | High |
-| F9 | Device Auto-Provisioning *(AZ-196)* | POST /devices | Admin API, User Mgmt | High |
-| ~~F10~~ | ~~OTA Update Check & Publish~~ | ~~POST /get-update + POST /resources/publish~~ | — | **REMOVED — post-cycle-1 (AZ-183 reverted, see security audit F-1)** |
+| F1 | User Login (dual token + MFA) | `POST /login` (+ `/login/mfa`) | Admin API, User Mgmt, Auth & Security | **Critical** |
+| F2 | User Registration | `POST /users` | Admin API, User Mgmt | High |
+| ~~F3~~ | ~~Encrypted Resource Download~~ | — | — | **REMOVED — cycle 2 early** |
+| ~~F4~~ | ~~Hardware Check~~ | — | — | **REMOVED — AZ-197** |
+| F5 | Resource Upload | `POST /resources` | Admin API, Resource Mgmt | Medium |
+| ~~F6~~ | ~~Installer Download~~ | — | — | **REMOVED — cycle 2 early** |
+| F7 | User Management (CRUD) | Various `/users/*` | Admin API, User Mgmt | Medium |
+| F8 | Detection Classes CRUD | `POST/PATCH/DELETE /classes` | Admin API, DetectionClassService | High |
+| F9 | Device Auto-Provisioning | `POST /devices` | Admin API, User Mgmt | High |
+| ~~F10~~ | ~~OTA Update Check & Publish~~ | — | — | **REMOVED — post-cycle-1** |
+| **F11** | **Refresh Token Rotation** *(AZ-531)* | `POST /token/refresh` | Admin API, RefreshTokenService, AuthService, SessionService | **Critical** |
+| **F12** | **Logout / Revocation** *(AZ-535)* | `POST /logout`, `/logout/all`, `/sessions/{sid}/revoke` | Admin API, SessionService | High |
+| **F13** | **Mission Token Issuance** *(AZ-533)* | `POST /sessions/mission` | Admin API, MissionTokenService, SessionService, AuthService | High |
+| **F14** | **MFA Enrollment & Confirmation** *(AZ-534)* | `POST /users/me/mfa/{enroll,confirm,disable}` | Admin API, MfaService, AuditLog | High |
+| **F15** | **Verifier Revocation Snapshot** *(AZ-535)* | `GET /sessions/revoked?since=` | Admin API, SessionService | **Critical** for verifier fleet |
+| **F16** | **Account Lockout & Rate Limit** *(AZ-537)* | (cross-cuts F1) | Admin API rate-limiter middleware, UserService, AuditLog | High |
+| **F17** | **JWKS Publication** *(AZ-532)* | `GET /.well-known/jwks.json` | Admin API, JwtSigningKeyProvider | **Critical** for verifier fleet |

 ## Flow Dependencies

 | Flow | Depends On | Shares Data With |
 |------|-----------|-----------------|
-| F1 | — | All other flows (produces JWT token) |
-| F2 | — | F1, F9 (creates user records — including device users via F9) |
-| F5 | F1 (requires JWT) | — |
-| F7 | F1 (requires JWT, ApiAdmin role) | — |
-| F8 | F1 (requires JWT, ApiAdmin role) | UI Detection Classes table |
-| F9 | F1 (requires JWT, ApiAdmin role) | F2 (writes a user row, but reuses `RegisterUser` end-to-end), F1 (provisioned devices later log in) |
+| F1 | F17 (signing keys must exist), F16 (rate limit gate) | F11 (refresh chain), F12 (sid is the revocation key), F14 (MFA branch) |
+| F2 | — | F1 (created users can log in) |
+| F5 | F1 / F11 (access token) | — |
+| F7 | F1 / F11 + ApiAdmin | F12 (disabling a user revokes their sessions) |
+| F8 | F1 / F11 + ApiAdmin | UI |
+| F9 | F1 / F11 + ApiAdmin | F1 (provisioned devices later log in) |
+| F11 | F1 (created the family) | F12 (rotation is the same row store) |
+| F12 | F1 / F11 (sid claim) | F15 (revoked rows surface here) |
+| F13 | F1 / F11 (pilot's interactive token) | F12 (auto-revoke prior aircraft mission rows) |
+| F14 | F1 (caller is authenticated) | F1 (the MFA branch consumes enrolled state) |
+| F15 | — (verifier role only) | F12 (consumes revocation rows) |
+| F16 | — | F1, F11 (gates them) |
+| F17 | — | F1, F11, F13, F14 (every signed token), F15 (verifiers cache JWKS) |

 ---

-## Flow F1: User Login
+## Flow F1: User Login (dual token + MFA) *(rebuilt cycle 2)*

 ### Description
-A user submits email/password credentials. The system validates them against the database and returns a signed JWT token for subsequent authenticated requests.
+A user submits email/password credentials. The system enforces per-IP and per-account rate limits + lockout (F16), verifies the password with constant-time Argon2id (lazily migrating from SHA-384 if needed — AZ-536), and either:
+- (no MFA) issues a short-lived ES256 access token + opaque refresh token bound to a new session row, OR
+- (MFA enabled) issues a short-lived `mfa_token` (JWT, audience `mfa-step`, signed by the active ES256 key) and waits for `POST /login/mfa` to complete the second factor.

 ### Preconditions
- User account exists in the database
- User knows correct password
+- User account exists, is enabled, and is not within an active lockout window
+- Per-IP rate-limit bucket has remaining permits
+- Per-account sliding-window failed-login count is below threshold
+- For the MFA branch: user has previously enrolled and confirmed MFA (F14)

 ### Sequence Diagram

@@ -47,27 +67,84 @@ A user submits email/password credentials. The system validates them against the
 sequenceDiagram
    participant Client
    participant API as Admin API
+    participant RL as RateLimiter (per-IP, AZ-537)
    participant US as UserService
+    participant AL as AuditLog
+    participant Sec as Security (Argon2id, AZ-536)
    participant DB as PostgreSQL
+    participant Mfa as MfaService
+    participant RT as RefreshTokenService
    participant Auth as AuthService
+    participant SS as SessionService

    Client->>API: POST /login {email, password}
+    API->>RL: per-IP sliding window check
+    alt rate-limited
+        RL-->>Client: 429 + Retry-After
+    end
    API->>US: ValidateUser(request)
-    US->>DB: SELECT user WHERE email = ?
-    DB-->>US: User record
-    US->>US: Compare password hash
+    US->>DB: SELECT users WHERE email=? (read conn)
+    US->>AL: CountRecentFailedLogins(email, window)
+    alt account locked OR per-account threshold exceeded
+        US-->>API: BusinessException(AccountLocked / LoginRateLimited, RetryAfterSeconds)
+        API-->>Client: 423 / 429 + Retry-After
+    end
+    US->>Sec: VerifyPassword(presented, stored)
+    alt VerifyResult.Ok=false
+        US->>AL: RecordLoginFailed
+        US->>DB: UPDATE failed_login_count, lockout_until
+        US-->>API: WrongPassword (or NoEmailFound)
+        API-->>Client: 409
+    end
+    alt VerifyResult.NeedsRehash=true
+        US->>Sec: HashPassword (Argon2id)
+        US->>DB: UPDATE password_hash (lazy migrate)
+    end
+    US->>AL: RecordLoginSuccess
+    US->>DB: UPDATE failed_login_count=0, last_login=now()
    US-->>API: User entity
-    API->>Auth: CreateToken(user)
-    Auth-->>API: JWT string
-    API-->>Client: 200 OK {token}
+
+    alt user.MfaEnabled
+        API->>Mfa: IssueMfaStepToken(userId)
+        Mfa-->>API: short-lived JWT (mfa_pending=true)
+        API-->>Client: 200 OK {mfa_required: true, mfa_token, expires_in: 300}
+    else
+        API->>RT: IssueForNewLogin(userId, mfaAuthenticated=false)
+        RT->>DB: INSERT INTO sessions (new id, family_id=id, refresh_hash, expires_at, mfa_authenticated=false)
+        RT-->>API: (opaqueRefreshToken, Session)
+        API->>Auth: CreateToken(user, sessionId=Session.Id, jti=new, amr=["pwd"])
+        Auth-->>API: AccessToken (ES256)
+        opt user.Role == CompanionPC
+            API->>SS: RevokeMissionsForAircraft(user.Id)  // F13 / AZ-533 AC-4
+        end
+        API-->>Client: 200 OK LoginResponse {AccessToken, AccessExp, RefreshToken, RefreshExp}
+    end
+
+    Note over Client,API: MFA branch only:
+    Client->>API: POST /login/mfa {mfa_token, code}
+    API->>RL: per-IP sliding window check
+    API->>Mfa: ValidateMfaStepToken(mfa_token) -> userId
+    API->>US: GetById(userId)
+    API->>Mfa: VerifyForLogin(userId, code) -> amr
+    Mfa->>DB: TOTP verify against decrypted mfa_secret OR recovery code consume
+    Mfa->>AL: RecordMfaLoginSuccess (or MfaRecoveryUsed)
+    API->>RT: IssueForNewLogin(userId, mfaAuthenticated=true)
+    API->>Auth: CreateToken(user, sessionId, jti, amr=["pwd","mfa"])
+    API-->>Client: 200 OK LoginResponse
 ```

 ### Error Scenarios

 | Error | Where | Detection | Recovery |
 |-------|-------|-----------|----------|
-| Email not found | UserService.ValidateUser | No DB record | 409: NoEmailFound (code 10) |
-| Wrong password | UserService.ValidateUser | Hash mismatch | 409: WrongPassword (code 30) |
+| Per-IP limit exceeded | Rate-limiter middleware | sliding window | 429 + `Retry-After` |
+| Account locked | UserService.ValidateUser | `now() < lockout_until` | 423 `AccountLocked` (code 50) + `Retry-After` |
+| Per-account threshold | UserService.ValidateUser | failed-login count over window | 429 `LoginRateLimited` (code 51) + `Retry-After` |
+| Email not found | UserService.ValidateUser | No DB record | 409 `NoEmailFound` (code 10) |
+| Wrong password | UserService.ValidateUser | `VerifyPassword.Ok=false` | 409 `WrongPassword` (code 30) — also increments `failed_login_count` |
+| User disabled | UserService.ValidateUser | `is_enabled=false` | 409 `UserDisabled` (code 38) |
+| MFA token invalid | MfaService.ValidateMfaStepToken | bad signature / wrong audience / expired | 401 `InvalidMfaToken` (code 61) |
+| MFA code wrong | MfaService.VerifyForLogin | TOTP and recovery both miss | 401 `InvalidMfaCode` (code 59) — `mfa_login_failed` audit row |

 ---

@@ -96,7 +173,7 @@ sequenceDiagram
    API->>US: RegisterUser(request)
    US->>DB: SELECT user WHERE email = ?
    DB-->>US: null (no duplicate)
-    US->>US: Hash password (SHA-384)
+    US->>US: Hash password (Argon2id, AZ-536)
    US->>DB: INSERT user (admin connection)
    DB-->>US: OK
    US-->>API: void
@@ -170,7 +247,9 @@ Admin operations: list users, change role, enable/disable, update queue offsets,
 ### Preconditions
 - Caller has ApiAdmin role (for most operations)

-All operations follow the same pattern: API endpoint → UserService method → DbFactory.RunAdmin → PostgreSQL UPDATE/DELETE. Cache is invalidated for affected user keys after writes (the `UpdateQueueOffsets` path is the only remaining cache-invalidation site post-AZ-197).
+All operations follow the same pattern: API endpoint → UserService method → DbFactory.RunAdmin → PostgreSQL UPDATE/DELETE. Cache is invalidated for affected user keys after writes.
+
+> **Cycle 2 cross-cut**: `PUT /users/{email}/disable` now also calls `SessionService.RevokeAllForUser` so disabling a user instantly cuts every active session. Verifiers pick this up via F15 within their poll cadence.

 ---

@@ -241,7 +320,7 @@ sequenceDiagram
 ## Flow F9: Device Auto-Provisioning *(AZ-196, 2026-05-13)*

 ### Description
-ApiAdmin requests a fresh CompanionPC device user. The server allocates the next sequential serial (`azj-NNNN`), generates a 32-char hex password, persists the user with the SHA-384 hash, and returns the plaintext credentials exactly once. The provisioning script (out-of-tree) embeds the values into the device's `device.conf`.
+ApiAdmin requests a fresh CompanionPC device user. The server allocates the next sequential serial (`azj-NNNN`), generates a 32-char hex password, persists the user with an Argon2id hash (cycle 2 — AZ-536), and returns the plaintext credentials exactly once. The provisioning script (out-of-tree) embeds the values into the device's `device.conf`.

 ### Preconditions
 - Caller has ApiAdmin role (`apiAdminPolicy`)
@@ -262,7 +341,7 @@ sequenceDiagram
    US->>US: nextNumber = parse(lastEmail.suffix) + 1 (or 0)
    US->>US: serial = "azj-" + nextNumber.PadLeft(4)
    US->>US: password = ToHex(RandomBytes(16))   // 32 hex chars
-    US->>DB: INSERT user {Email=serial@domain, PasswordHash=SHA384(password), Role=CompanionPC, IsEnabled=true} (admin conn)
+    US->>DB: INSERT user {Email=serial@domain, PasswordHash=Argon2id(password), Role=CompanionPC, IsEnabled=true} (admin conn)
    DB-->>US: OK
    US-->>API: RegisterDeviceResponse {Serial, Email, Password}
    API-->>Admin: 200 OK {Serial, Email, Password}
@@ -288,3 +367,383 @@ Reasons:
 2. The OTA delivery model is itself a leftover from the installer-shipping era; the target architecture (browser-only SaaS + fTPM-secured Jetsons) does not need it.

 The `apiUploaderPolicy` definition was removed from `Program.cs`; the `RoleEnum.ResourceUploader` enum value remains as data (the seed `uploader@azaion.com` user still uses it for negative-auth tests) but is no longer wired to any endpoint.
+
+---
+
+## Flow F11: Refresh Token Rotation *(AZ-531, 2026-05-14)*
+
+### Description
+The client presents an opaque refresh token; the server validates it, rotates it (marks the old row as `revoked_reason='rotated'`), inserts a new row in the same `family_id`, and mints a new ES256 access token. Reuse of an already-rotated token revokes the entire family with `reason='reuse_detected'` (and triggers F15 surfacing for verifiers).
+
+### Preconditions
+- Refresh token is well-formed and corresponds to a non-revoked, non-expired session row
+- The session is within both the sliding window (`SessionConfig.RefreshSlidingHours`) and the absolute cap (`SessionConfig.RefreshAbsoluteHours` measured from `family_started_at`)
+
+### Sequence Diagram
+
+```mermaid
+sequenceDiagram
+    participant Client
+    participant API as Admin API
+    participant RT as RefreshTokenService
+    participant US as UserService
+    participant Auth as AuthService
+    participant SS as SessionService
+    participant DB as PostgreSQL
+
+    Client->>API: POST /token/refresh {refreshToken}
+    API->>RT: Rotate(opaqueToken)
+    RT->>DB: SELECT * FROM sessions WHERE refresh_hash = SHA256(token)
+    alt row missing
+        RT-->>API: 401 InvalidRefreshToken
+    end
+    alt row.revoked_reason = 'rotated' (reuse!)
+        RT->>DB: UPDATE sessions SET revoked_at=now, revoked_reason='reuse_detected' WHERE family_id = row.family_id AND revoked_at IS NULL
+        RT-->>API: 401 InvalidRefreshToken
+    end
+    alt row.revoked_at IS NOT NULL OR row.expires_at <= now
+        RT-->>API: 401 InvalidRefreshToken
+    end
+    RT->>DB: UPDATE sessions SET revoked_at=now, revoked_reason='rotated', last_used_at=now WHERE id = row.id
+    RT->>DB: INSERT INTO sessions (new id, family_id=row.family_id, refresh_hash=SHA256(newToken), parent_session_id=row.id, expires_at=now+sliding, mfa_authenticated=row.mfa_authenticated)
+    RT-->>API: (newOpaqueToken, newSession)
+    API->>US: GetById(newSession.UserId)
+    US-->>API: User
+    API->>Auth: CreateToken(user, sessionId=newSession.Id, jti=new, amr= ['pwd','mfa'] if mfaAuthenticated else ['pwd'])
+    Auth-->>API: AccessToken
+    opt user.Role == CompanionPC
+        API->>SS: RevokeMissionsForAircraft(user.Id)
+    end
+    API-->>Client: 200 OK LoginResponse {AccessToken, AccessExp, RefreshToken=newOpaqueToken, RefreshExp=newSession.ExpiresAt}
+```
+
+### Error Scenarios
+
+| Error | Where | Detection | Recovery |
+|-------|-------|-----------|----------|
+| Token missing / not in DB | RefreshTokenService.Rotate | `SHA256(token)` not found | 401 `InvalidRefreshToken` |
+| Reuse detected | RefreshTokenService.Rotate | row already `revoked_reason='rotated'` | 401 `InvalidRefreshToken` + entire family revoked (visible via F15) |
+| Sliding window expired | RefreshTokenService.Rotate | `expires_at <= now()` | 401 `InvalidRefreshToken` |
+| Absolute cap exceeded | RefreshTokenService.Rotate | `now() - family_started_at > RefreshAbsoluteHours` | 401 `InvalidRefreshToken` |
+| User missing (race with deletion) | API | `UserService.GetById` returns null | 401 `InvalidRefreshToken` |
+
+---
+
+## Flow F12: Logout / Revocation *(AZ-535, 2026-05-14)*
+
+### Description
+Three endpoints share `SessionService.RevokeBySid` / `RevokeAllForUser`:
+- `POST /logout` — revoke caller's current `sid` (idempotent; returns `{ alreadyRevoked }`)
+- `POST /logout/all` — revoke every active session for the caller's user
+- `POST /sessions/{sid}/revoke` *(ApiAdmin)* — admin revoke-by-sid
+
+All revocations write `revoked_at`, `revoked_reason`, and `revoked_by_user_id`; the rows surface to verifiers via F15 within the next poll window.
+
+### Preconditions
+- `/logout` / `/logout/all` — caller is authenticated; the access token's `sid` claim is well-formed
+- `/sessions/{sid}/revoke` — caller is `ApiAdmin`
+
+### Sequence Diagram
+
+```mermaid
+sequenceDiagram
+    participant Client
+    participant API as Admin API
+    participant SS as SessionService
+    participant DB as PostgreSQL
+
+    Note over Client,API: Self logout
+    Client->>API: POST /logout (Bearer access)
+    API->>API: ParseSidClaim(user) -> sid
+    API->>API: ParseUserIdClaim(user) -> caller
+    API->>SS: RevokeBySid(sid, caller, 'logged_out')
+    SS->>DB: UPDATE sessions SET revoked_at=now, revoked_reason='logged_out', revoked_by_user_id=caller WHERE id=sid AND revoked_at IS NULL
+    SS-->>API: alreadyRevoked: bool
+    API-->>Client: 200 OK { alreadyRevoked }
+
+    Note over Client,API: Logout-all
+    Client->>API: POST /logout/all
+    API->>SS: RevokeAllForUser(caller, caller, 'logged_out_all')
+    SS->>DB: UPDATE ... WHERE user_id=caller AND revoked_at IS NULL
+    SS-->>API: int (rows revoked)
+    API-->>Client: 200 OK { revoked }
+
+    Note over Client,API: Admin revoke-by-sid
+    Client->>API: POST /sessions/{sid}/revoke (ApiAdmin)
+    API->>SS: RevokeBySid(sid, admin, 'admin_revoked')
+    SS->>DB: UPDATE ... WHERE id=sid AND revoked_at IS NULL
+    SS-->>API: alreadyRevoked: bool
+    API-->>Client: 200 OK { alreadyRevoked }
+```
+
+### Error Scenarios
+
+| Error | Where | Detection | Recovery |
+|-------|-------|-----------|----------|
+| Missing/malformed `sid` claim | ParseSidClaim | not a Guid | 401 `InvalidRefreshToken` |
+| Sid not in DB (admin path) | SessionService.RevokeBySid | row not found | 404 `SessionNotFound` |
+| Already revoked | SessionService.RevokeBySid | UPDATE affected 0 rows | 200 OK with `alreadyRevoked: true` (idempotent) |
+
+---
+
+## Flow F13: Mission Token Issuance *(AZ-533, 2026-05-14)*
+
+### Description
+A pilot (an authenticated interactive user) requests a long-lived no-refresh access token bound to one aircraft and one mission. Before signing the token, the server inserts a `class='mission'` session row (so `sid` is bound), and revokes any previously-active mission sessions for that aircraft (`reason='aircraft_reconnected'`).
+
+### Preconditions
+- Caller is authenticated (interactive token; AMR can be `["pwd"]` or `["pwd","mfa"]` — F1 follow-up tightens this to require `mfa` once policy is set)
+- `request.aircraftId` resolves to an existing user with `Role = CompanionPC`
+- `request.missionId` matches the validation pattern; `request.plannedDurationH` is within bounds
+
+### Sequence Diagram
+
+```mermaid
+sequenceDiagram
+    participant Pilot
+    participant API as Admin API
+    participant MTS as MissionTokenService
+    participant SS as SessionService
+    participant US as UserService
+    participant Auth as AuthService
+    participant DB as PostgreSQL
+
+    Pilot->>API: POST /sessions/mission {aircraftId, missionId, plannedDurationH, region}
+    API->>MTS: Issue(pilotId, request)
+    MTS->>US: GetById(aircraftId) (read conn)
+    alt aircraft missing or wrong role
+        MTS-->>API: 400 AircraftNotFound
+    end
+    MTS->>SS: RevokeMissionsForAircraft(aircraftId)  // AC-4
+    SS->>DB: UPDATE sessions SET revoked_at=now, revoked_reason='aircraft_reconnected' WHERE aircraft_id=? AND class='mission' AND revoked_at IS NULL
+    MTS->>DB: INSERT INTO sessions (id, user_id=aircraftId, class='mission', aircraft_id=aircraftId, refresh_hash=NULL, expires_at=now + plannedDurationH)
+    MTS->>Auth: CreateToken(aircraftUser, sessionId=newSid, jti, amr=['pwd','mission'])
+    Auth-->>MTS: AccessToken
+    MTS-->>API: MissionSessionResponse {access_token, expires_at, mission_id, aircraft_id}
+    API-->>Pilot: 200 OK
+```
+
+### Error Scenarios
+
+| Error | Where | Detection | Recovery |
+|-------|-------|-----------|----------|
+| Validation failure | FluentValidation / MissionTokenService | bad `mission_id` pattern, `plannedDurationH` out of bounds | 400 `InvalidMissionRequest` (code 54) |
+| Aircraft not a CompanionPC | MissionTokenService.Issue | role mismatch | 400 `AircraftNotFound` (code 55) |
+
+---
+
+## Flow F14: MFA Enrollment & Confirmation *(AZ-534, 2026-05-14)*
+
+### Description
+Three-step user-initiated lifecycle:
+1. **Enroll** — server generates a new TOTP secret, encrypts it via `IDataProtector` (purpose `Azaion.Mfa.Secret`), persists with `mfa_enabled=false`, returns base32 secret + otpauth URL + QR PNG bytes.
+2. **Confirm** — client submits a TOTP code; on success server flips `mfa_enabled=true`, generates 10 single-use Argon2id-hashed recovery codes, and returns them once.
+3. **Disable** — requires both password + a current TOTP; server clears all MFA columns.
+
+### Preconditions
+- Caller is authenticated
+- For Confirm: a prior Enroll call left the encrypted secret on the user
+- For Disable: `mfa_enabled = true`
+
+### Sequence Diagram
+
+```mermaid
+sequenceDiagram
+    participant User
+    participant API as Admin API
+    participant Mfa as MfaService
+    participant DP as IDataProtector
+    participant Sec as Security (Argon2id)
+    participant AL as AuditLog
+    participant DB as PostgreSQL
+
+    Note over User,API: ENROLL
+    User->>API: POST /users/me/mfa/enroll {password}
+    API->>Mfa: Enroll(userId, password)
+    Mfa->>DB: SELECT user
+    Mfa->>Sec: VerifyPassword(presented, stored)
+    Mfa->>Mfa: Generate 20-byte secret, base32 encode
+    Mfa->>DP: Protect(base32) -> encrypted base64
+    Mfa->>DB: UPDATE users SET mfa_secret = encrypted, mfa_enrolled_at = now, mfa_enabled=false
+    Mfa->>AL: RecordMfaEnroll
+    Mfa-->>API: MfaEnrollResponse { secret_base32, otpauth_url, qr_png }
+    API-->>User: 200 OK
+
+    Note over User,API: CONFIRM
+    User->>API: POST /users/me/mfa/confirm {code}
+    API->>Mfa: Confirm(userId, code)
+    Mfa->>DP: Unprotect(stored) -> base32 secret
+    Mfa->>Mfa: TOTP verify
+    alt code wrong
+        Mfa-->>API: 401 InvalidMfaCode
+    end
+    Mfa->>Mfa: Generate 10 recovery codes
+    Mfa->>Sec: HashPassword each (Argon2id)
+    Mfa->>DB: UPDATE users SET mfa_enabled=true, mfa_recovery_codes = jsonb([{ hash, used_at=null } x10]), mfa_last_used_window=current_step
+    Mfa->>AL: RecordMfaConfirm
+    Mfa-->>API: { recovery_codes: [...] }
+    API-->>User: 200 OK { mfaEnabled: true, recovery_codes }
+
+    Note over User,API: DISABLE
+    User->>API: POST /users/me/mfa/disable {password, code}
+    API->>Mfa: Disable(userId, password, code)
+    Mfa->>Sec: VerifyPassword
+    Mfa->>Mfa: TOTP verify
+    Mfa->>DB: UPDATE users SET mfa_enabled=false, mfa_secret=NULL, mfa_recovery_codes=NULL, mfa_enrolled_at=NULL, mfa_last_used_window=NULL
+    Mfa->>AL: RecordMfaDisable
+    Mfa-->>API: ok
+    API-->>User: 200 OK { mfaEnabled: false }
+```
+
+### Error Scenarios
+
+| Error | Where | Detection | Recovery |
+|-------|-------|-----------|----------|
+| Already enrolled (Enroll) | MfaService.Enroll | `mfa_enabled=true` | 409 `MfaAlreadyEnabled` (code 56) |
+| Not enrolling (Confirm) | MfaService.Confirm | `mfa_secret IS NULL` | 409 `MfaNotEnrolling` (code 57) |
+| Not enabled (Disable) | MfaService.Disable | `mfa_enabled=false` | 409 `MfaNotEnabled` (code 58) |
+| Wrong password | Sec.VerifyPassword | hash mismatch | 409 `WrongPassword` (code 30) |
+| Wrong TOTP code | MfaService TOTP path | code/window miss | 401 `InvalidMfaCode` (code 59) |
+
+---
+
+## Flow F15: Verifier Revocation Snapshot *(AZ-535, 2026-05-14)*
+
+### Description
+A `Service`-role identity (verifier fleet) polls `GET /sessions/revoked?since={iso8601}` periodically. The server returns every session whose `revoked_at >= since` and `expires_at > now()` so verifiers can deny tokens whose `sid` appears in the snapshot.
+
+The `since` parameter is **clamped to a 12-hour floor** server-side so a buggy verifier asking for "everything since 1970" doesn't trigger a multi-million-row table scan. Verifiers should clock-skew-tolerate by stepping `since` back ~30s on each poll.
+
+### Preconditions
+- Caller has role `Service` or `ApiAdmin` (`revocationReaderPolicy`)
+
+### Sequence Diagram
+
+```mermaid
+sequenceDiagram
+    participant Verifier
+    participant API as Admin API
+    participant SS as SessionService
+    participant DB as PostgreSQL
+
+    Verifier->>API: GET /sessions/revoked?since=2026-05-14T05:30:00Z
+    API->>API: clamp since to max(now-12h, since)
+    API->>SS: GetRevokedSince(effectiveSince)
+    SS->>DB: SELECT id, expires_at, revoked_at, revoked_reason FROM sessions WHERE revoked_at >= ? AND expires_at > now() ORDER BY revoked_at
+    DB-->>SS: rows (uses sessions_revoked_at_idx)
+    SS-->>API: IReadOnlyList<RevokedSession>
+    API-->>Verifier: 200 OK [{ sid, exp, revokedAt, reason }, ...] + Cache-Control: no-cache
+```
+
+### Error Scenarios
+
+| Error | Where | Detection | Recovery |
+|-------|-------|-----------|----------|
+| Wrong role | API authorization | not Service/ApiAdmin | 403 Forbidden |
+| `since` missing | API | bind null `DateTime?` | clamp falls back to `now-12h` |
+
+---
+
+## Flow F16: Account Lockout & Per-IP Rate Limit *(AZ-537, 2026-05-14)*
+
+### Description
+Cross-cuts F1 and F11. Two layers:
+1. **Per-IP** — ASP.NET Core `RateLimiter` middleware (`SlidingWindowRateLimiter`) attached to `/login` and `/login/mfa` via the `login-per-ip` policy. Rejection sets `429` and stamps `Retry-After` from the lease metadata.
+2. **Per-account + lockout** — DB-backed in `UserService.ValidateUser`:
+   - Read `failed_login_count` and `lockout_until` from `users`.
+   - If `now() < lockout_until` → throw `BusinessException(AccountLocked, RetryAfterSeconds = LockoutUntil - now)`.
+   - Else: count `audit_events` rows where `event_type='login_failed' AND email=? AND occurred_at >= now - PerAccountWindowSeconds`. If over threshold → throw `BusinessException(LoginRateLimited, RetryAfterSeconds = PerAccountWindowSeconds)`.
+   - On wrong password: `RecordLoginFailed` + UPDATE `failed_login_count = failed_login_count + 1`. If new count >= `ConsecutiveFailureThreshold` → set `lockout_until = now + LockoutSeconds`, `RecordLoginLockout`, throw `AccountLocked`.
+   - On success: `RecordLoginSuccess` + UPDATE `failed_login_count = 0`, `lockout_until = NULL`.
+
+### Preconditions
+- `AuthConfig.RateLimit.*` and `AuthConfig.Lockout.*` are non-zero
+- `audit_events` table exists
+
+### Sequence Diagram
+
+```mermaid
+sequenceDiagram
+    participant Client
+    participant Mid as RateLimiter middleware
+    participant API as Admin API
+    participant US as UserService
+    participant AL as AuditLog
+    participant DB as PostgreSQL
+
+    Client->>Mid: POST /login {email, password}
+    Mid->>Mid: SlidingWindow per-IP check
+    alt no permits
+        Mid-->>Client: 429 + Retry-After
+    end
+    Mid->>API: forward
+    API->>US: ValidateUser
+    US->>DB: SELECT users (read)
+    US->>AL: CountRecentFailedLogins(email, window)
+    alt account locked OR threshold exceeded
+        US->>AL: RecordLoginFailed (or RecordLoginLockout if newly locked)
+        US-->>API: BusinessException(AccountLocked / LoginRateLimited, RetryAfterSeconds)
+        API-->>Client: 423 / 429 + Retry-After
+    end
+    US->>US: VerifyPassword
+    alt wrong password
+        US->>AL: RecordLoginFailed
+        US->>DB: UPDATE failed_login_count++; lockout_until = now + LockoutSeconds (if newly over)
+        US-->>API: BusinessException(WrongPassword)
+        API-->>Client: 409
+    end
+    US->>AL: RecordLoginSuccess
+    US->>DB: UPDATE failed_login_count = 0, lockout_until = NULL, last_login = now
+    US-->>API: User
+```
+
+### Error Scenarios
+
+| Error | Where | Detection | Recovery |
+|-------|-------|-----------|----------|
+| Per-IP limit | RateLimiter middleware | sliding window | 429 + `Retry-After` |
+| Account locked | UserService.ValidateUser | `now < lockout_until` | 423 `AccountLocked` + `Retry-After` |
+| Per-account threshold | UserService.ValidateUser | `audit_events` count over window | 429 `LoginRateLimited` + `Retry-After` |
+
+---
+
+## Flow F17: JWKS Publication *(AZ-532, 2026-05-14)*
+
+### Description
+`GET /.well-known/jwks.json` (anonymous) returns the JSON Web Key Set containing one entry per loaded ES256 key. Verifiers cache for 1 hour (`Cache-Control: public, max-age=3600`).
+
+### Preconditions
+- `JwtConfig.KeysFolder` exists with at least one well-formed P-256 PEM
+- `JwtConfig.ActiveKid` matches one of the loaded files (the others are still served, allowing verifiers to validate already-issued tokens during a key rotation)
+
+### Sequence Diagram
+
+```mermaid
+sequenceDiagram
+    participant Verifier
+    participant API as Admin API
+    participant JKP as JwtSigningKeyProvider
+    participant FS as Filesystem
+
+    Note over JKP,FS: At app startup
+    API->>JKP: ctor (eager)
+    JKP->>FS: scan KeysFolder/*.pem
+    JKP->>JKP: validate P-256 curve, build EcdsaSecurityKey list
+    JKP-->>API: ready (or fail-fast if 0 keys)
+
+    Note over Verifier,API: Per-poll
+    Verifier->>API: GET /.well-known/jwks.json
+    API->>JKP: All
+    JKP-->>API: list of JwtSigningKey
+    API->>API: project to JWK { kty:EC, crv:P-256, kid, use:sig, alg:ES256, x, y }
+    API-->>Verifier: 200 OK { keys: [...] } + Cache-Control: public, max-age=3600
+```
+
+### Error Scenarios
+
+| Error | Where | Detection | Recovery |
+|-------|-------|-----------|----------|
+| No keys / malformed PEM | JwtSigningKeyProvider ctor | startup crash (intentional) | Operator fix + restart |
+| Wrong curve in PEM | JwtSigningKeyProvider ctor | startup crash | Operator fix + restart |
+
+> **Rotation procedure**: drop a new PEM into `KeysFolder`, set `JwtConfig:ActiveKid` to the new kid, restart. Already-issued tokens remain verifiable until their `exp`. Old PEMs are physically removed only after the longest possible token TTL has elapsed.
@@ -811,3 +811,665 @@ The scenarios `FT-P-21`, `FT-P-22`, `FT-P-23` are retained here as ID placeholde
 **Max execution time**: 5s

 Note: AZ-197 AC-1 (resource download works without `Hardware`) is implicitly covered by the existing FT-P-09 / FT-P-10 scenarios once their request bodies are aligned with the new wire shape. AZ-197 AC-3..AC-8 are internal-signature / build-system invariants and are verified at build/CI time, not via a blackbox HTTP scenario.
+
+---
+
+## Cycle 2 Additions (2026-05-14) — Auth Modernization (AZ-529 + AZ-530)
+
+The scenarios below were appended during the existing-code cycle 2 Test-Spec Sync (autodev Step 12) for the eight tasks under AZ-529 (Auth Mechanism Modernization) and AZ-530 (CMMC Compliance Hardening): AZ-531 (refresh-token flow), AZ-532 (asymmetric signing + JWKS), AZ-533 (mission-token UAV), AZ-534 (TOTP 2FA), AZ-535 (logout + revocation), AZ-536 (Argon2id), AZ-537 (rate-limit + lockout), AZ-538 (CORS HTTPS-only + HSTS). Numbering continues from FT-P-23 / FT-N-16. Security-only ACs live in `security-tests.md`.
+
+### Argon2id Password Hashing (AZ-536)
+
+#### FT-P-24: Legacy SHA-384 Password Still Validates
+
+**Summary**: A user whose `password_hash` is in the pre-AZ-536 unsalted SHA-384 format can still log in with the correct password.
+**Traces to**: AZ-536 AC-2
+**Category**: Authentication
+
+**Preconditions**:
+- Seed user `legacy@azaion.com` with `password_hash` set to `Convert.ToBase64String(SHA384.HashData("LegacyPwd1!"))` (the historical format)
+
+**Input data**: `{"email":"legacy@azaion.com","password":"LegacyPwd1!"}`
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | POST /login with the legacy user's credentials | HTTP 200, dual-token body (per AZ-531) |
+
+**Expected outcome**: HTTP 200, login succeeds against legacy hash format
+**Max execution time**: 5s (note: Argon2id verify cost is incurred only on the post-login re-hash)
+
+---
+
+#### FT-P-25: Successful Legacy Login Re-Hashes to Argon2id
+
+**Summary**: After FT-P-24 succeeds, the user's `password_hash` is silently upgraded to Argon2id PHC format and the same plaintext continues to validate.
+**Traces to**: AZ-536 AC-3
+**Category**: Authentication
+
+**Preconditions**:
+- FT-P-24 has just executed successfully for `legacy@azaion.com`
+
+**Input data**: `{"email":"legacy@azaion.com","password":"LegacyPwd1!"}`
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | Read `users.password_hash` for `legacy@azaion.com` directly from DB | Value starts with `$argon2id$v=19$m=` and parses to m ≥ 65536, t ≥ 3, p ≥ 1 |
+| 2 | POST /login with the same plaintext password again | HTTP 200, dual-token body |
+
+**Expected outcome**: Hash format upgraded to Argon2id PHC; subsequent login still works
+**Max execution time**: 5s
+
+---
+
+#### FT-N-17: Wrong Password Fails for Both Hash Formats
+
+**Summary**: Wrong password is rejected with the same error (`WrongPassword`) regardless of whether the stored hash is legacy SHA-384 or Argon2id.
+**Traces to**: AZ-536 AC-4
+**Category**: Authentication
+
+**Preconditions**:
+- One user with legacy SHA-384 hash, one user with Argon2id hash already in DB
+
+**Input data**: Wrong password against each user
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | POST /login (legacy user, wrong pwd) | HTTP 409, ExceptionEnum=WrongPassword (code 30) |
+| 2 | POST /login (Argon2id user, wrong pwd) | HTTP 409, ExceptionEnum=WrongPassword (code 30) |
+
+**Expected outcome**: Same error code on both code paths; no information leak about hash format
+**Max execution time**: 5s per attempt (Argon2id cost incurred regardless of success/failure)
+
+---
+
+### /login Rate Limit + Account Lockout (AZ-537)
+
+#### FT-P-26: Successful Login Resets the Failed-Attempt Counter
+
+**Summary**: After some wrong-password attempts (within budget), a successful login zeros `failed_login_count` and clears `lockout_until`.
+**Traces to**: AZ-537 AC-4
+**Category**: Authentication
+
+**Preconditions**:
+- User `alice@azaion.com` exists with Argon2id-hashed password
+
+**Input data**: 5 wrong-password attempts followed by 1 correct attempt
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | POST /login with wrong pwd × 5 (within rate-limit budget) | HTTP 409 each (WrongPassword) |
+| 2 | Read `users.failed_login_count` for alice | Value = 5 |
+| 3 | POST /login with correct pwd | HTTP 200, dual-token body |
+| 4 | Read `users.failed_login_count` and `lockout_until` for alice | `failed_login_count = 0`, `lockout_until IS NULL` |
+
+**Expected outcome**: Counter reset on success
+**Max execution time**: 30s (5× Argon2id verifies)
+
+---
+
+#### FT-P-27: Lockout Auto-Expires After Configured Duration
+
+**Summary**: A locked account becomes loginable again automatically once `lockout_until < now()`.
+**Traces to**: AZ-537 AC-5
+**Category**: Authentication
+
+**Preconditions**:
+- `Auth:Lockout:DurationMinutes` set to a small value (e.g. 1 minute) in the test env so the test does not have to wait 15 min
+- User `bob@azaion.com` exists with Argon2id hash
+
+**Input data**: 10 wrong attempts to trigger lockout, then a correct attempt after the duration window
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | POST /login with wrong pwd × 10 | first 9 → 409 WrongPassword; the 10th → 423 Locked OR 409 followed by lockout flag |
+| 2 | POST /login with correct pwd immediately | HTTP 423 Locked (account is locked) |
+| 3 | Wait `Auth:Lockout:DurationMinutes + 1s` | — |
+| 4 | POST /login with correct pwd | HTTP 200, dual-token body |
+
+**Expected outcome**: 423 → 200 transition once the lockout window expires
+**Max execution time**: 90s (depends on configured lockout duration in test env)
+
+---
+
+### CORS HTTPS-Only + HSTS (AZ-538)
+
+#### FT-P-28: HTTPS Origin Preflight Succeeds
+
+**Summary**: The CORS allow-list still admits the canonical `https://admin.azaion.com` origin and echoes the credentials flag.
+**Traces to**: AZ-538 AC-2
+**Category**: Cross-Origin
+
+**Preconditions**:
+- Admin API running with `AdminCorsPolicy` configured (post-AZ-538)
+
+**Input data**:
+- Method: OPTIONS
+- Path: /login
+- Header: `Origin: https://admin.azaion.com`
+- Header: `Access-Control-Request-Method: POST`
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | OPTIONS /login with the headers above | HTTP 204; `Access-Control-Allow-Origin: https://admin.azaion.com`; `Access-Control-Allow-Credentials: true` |
+
+**Expected outcome**: HTTPS origin preflight succeeds with credentials flag
+**Max execution time**: 5s
+
+---
+
+#### FT-P-29: Development Env — No HTTPS Redirect, No HSTS
+
+**Summary**: When `ASPNETCORE_ENVIRONMENT=Development`, plain HTTP requests to localhost still serve 200 responses with no `Strict-Transport-Security` header.
+**Traces to**: AZ-538 AC-5
+**Category**: Cross-Origin
+
+**Preconditions**:
+- Admin API running with `ASPNETCORE_ENVIRONMENT=Development` (the default test container env)
+
+**Input data**: GET http://localhost:8080/health/live
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | GET http://localhost:8080/health/live | HTTP 200; no `Strict-Transport-Security` header; no 307 redirect |
+
+**Expected outcome**: Dev workflow preserved — no redirect, no HSTS
+**Max execution time**: 5s
+
+---
+
+### Refresh-Token Flow (AZ-531)
+
+#### FT-P-30: /login Returns Dual Tokens
+
+**Summary**: Successful login returns both a short-lived access token (≈15 min) and an opaque refresh token; a `sessions` row is created.
+**Traces to**: AZ-531 AC-1
+**Category**: Authentication
+
+**Preconditions**:
+- Seed user without MFA enabled
+
+**Input data**: Valid email + password
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | POST /login | HTTP 200; body has `access_token` (JWT), `access_exp` ≈ now+15m ±60s, `refresh_token` (opaque ≥43 chars), `refresh_exp` |
+| 2 | Decode `access_token` payload | Contains `sub`, `iss`, `aud`, `exp`, `jti`, `sid` claims |
+| 3 | Query `sessions` table by `user_id` | Exactly one row with non-null `refresh_hash`, non-null `family_id`, `revoked_at IS NULL` |
+
+**Expected outcome**: Dual tokens issued, session row persisted, access token has short TTL
+**Max execution time**: 5s
+
+---
+
+#### FT-P-31: /token/refresh Rotates the Refresh Token
+
+**Summary**: A valid refresh token is exchanged for a new access + new refresh; the previous refresh is invalidated; the session chain extends via `parent_session_id`.
+**Traces to**: AZ-531 AC-2
+**Category**: Authentication
+
+**Preconditions**:
+- FT-P-30 just produced refresh token R1
+
+**Input data**: `{"refresh_token":"<R1>"}`
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | POST /token/refresh with R1 | HTTP 200; body has new `access_token`, new `refresh_token` (R2 ≠ R1), new `access_exp`, new `refresh_exp` |
+| 2 | POST /token/refresh with R1 again (same call) | HTTP 401 (R1 has been rotated; see AC-3 reuse-detection in NFT-SEC-08) |
+| 3 | Inspect `sessions` table | Original row's `refresh_hash` rotated; new row has `parent_session_id` chained to the previous row |
+
+**Expected outcome**: Rotation succeeds; old refresh dies; chain is preserved
+**Max execution time**: 5s
+
+---
+
+#### FT-P-32: Refresh Sliding + Absolute Expiry
+
+**Summary**: Refresh tokens slide on use up to the per-family absolute cap (12 h since the family's first issue); after the absolute cap, refresh fails.
+**Traces to**: AZ-531 AC-4
+**Category**: Authentication
+
+**Preconditions**:
+- A `sessions` family with `family_first_issued_at` set to `now() - 11h59m` (verified via DB seed) and a current valid refresh token R-current
+
+**Input data**: `{"refresh_token":"<R-current>"}`, called near and past the absolute cap
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | POST /token/refresh at family-age 11h59m | HTTP 200, rotation succeeds; sliding window extended |
+| 2 | Seed another family with `family_first_issued_at = now() - 12h01s` | — |
+| 3 | POST /token/refresh on that family | HTTP 401, body indicates absolute-expiry violation |
+
+**Expected outcome**: Sliding works inside 12 h; absolute cap rejects beyond
+**Max execution time**: 5s
+
+---
+
+### Asymmetric Signing + JWKS (AZ-532)
+
+#### FT-P-33: GET /.well-known/jwks.json Serves the Active Public Key
+
+**Summary**: The JWKS endpoint is anonymous, cacheable, and returns a well-formed JWKS containing the active EC P-256 public key with `kid`.
+**Traces to**: AZ-532 AC-2
+**Category**: Cryptography / Discovery
+
+**Preconditions**:
+- Admin running with an ES256 keypair loaded from `secrets/jwt_signing_key.pem`
+
+**Input data**: None (anonymous GET)
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | GET /.well-known/jwks.json (no JWT) | HTTP 200; `Content-Type: application/json`; `Cache-Control: public, max-age=3600` |
+| 2 | Parse body | `{"keys":[{"kty":"EC","crv":"P-256","kid":<non-empty>,"x":<base64url>,"y":<base64url>,"alg":"ES256","use":"sig"}, …]}` |
+
+**Expected outcome**: JWKS shape matches RFC 7517; cache headers present
+**Max execution time**: 5s
+
+---
+
+#### FT-P-34: Two-Key Overlap During Rotation
+
+**Summary**: When two signing keys are configured (`kid-A` active + `kid-B` standby), JWKS exposes both; tokens signed with the active key continue to verify; switching the active flag to `kid-B` produces `kid-B`-stamped tokens that also verify.
+**Traces to**: AZ-532 AC-3
+**Category**: Cryptography / Rotation
+
+**Preconditions**:
+- Two keys configured in `secrets/`: `jwt_signing_key_a.pem` (active), `jwt_signing_key_b.pem` (standby)
+
+**Input data**: Sequenced login + rotation toggle
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | GET /.well-known/jwks.json | Both `kid-A` and `kid-B` appear in `keys` array |
+| 2 | POST /login | Returned access token has `kid: kid-A` in header |
+| 3 | Toggle active key → `kid-B` (test-only admin endpoint or env reload) | — |
+| 4 | POST /login again | Returned access token has `kid: kid-B` in header |
+| 5 | Use either token against any protected endpoint | HTTP 200 (both verify against their respective public keys in JWKS) |
+
+**Expected outcome**: Overlap window allows both keys; verifiers can keep working through rotation
+**Max execution time**: 10s
+
+---
+
+### Mission-Token Issuance for UAV (AZ-533)
+
+#### FT-P-35: POST /sessions/mission Issues a Long-Lived Mission Token
+
+**Summary**: An authenticated pilot session can mint a mission-class access token with a duration ≈ `planned_duration_h + 1h` and no refresh token.
+**Traces to**: AZ-533 AC-1
+**Category**: Mission Sessions
+
+**Preconditions**:
+- Pilot user with valid (post-AZ-531) access token; MFA already proven within the session (post-AZ-534)
+- Aircraft user `UAV-117` with `Role=CompanionPC` exists
+
+**Input data**: `{"mission_id":"M-2026-05-14-042","aircraft_id":"UAV-117","planned_duration_h":9,"requested_scope":["GPS"]}`
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | POST /sessions/mission with the body above + pilot access token | HTTP 200; body has `access_token`, no `refresh_token`, `exp` ≈ now + 10h ±60s |
+| 2 | Decode token payload | `token_class = "mission"` |
+| 3 | Query `sessions` table | Row with `class='mission'`, `aircraft_id='UAV-117'`, `revoked_at IS NULL` |
+
+**Expected outcome**: Long-lived mission token issued; session persisted with class marker
+**Max execution time**: 5s
+
+---
+
+#### FT-P-36: Mission Token Carries Scope Claims
+
+**Summary**: The mission token's payload exposes `mission_id`, `aircraft_id`, `aud`, `permissions`, `sid`, `jti`.
+**Traces to**: AZ-533 AC-3
+**Category**: Mission Sessions
+
+**Preconditions**:
+- FT-P-35 just produced a mission token
+
+**Input data**: The mission token from FT-P-35
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | Decode mission token payload | `mission_id == "M-2026-05-14-042"`, `aircraft_id == "UAV-117"`, `aud == "satellite-provider"`, `permissions` contains `"GPS"`, `sid` non-empty, `jti` non-empty |
+
+**Expected outcome**: All scope claims present and correctly populated
+**Max execution time**: 5s
+
+---
+
+#### FT-P-37: Mission Token Auto-Revoked on Aircraft Reconnect
+
+**Summary**: When the aircraft user behind a mission session calls `/login` or `/token/refresh` again, every open mission session for that aircraft is marked `revoked_reason='post_flight_reconnect'` and the mission token stops working.
+**Traces to**: AZ-533 AC-4
+**Category**: Mission Sessions
+
+**Preconditions**:
+- Open mission session for `UAV-117` from FT-P-35 (token MT)
+
+**Input data**: A `/login` from the `UAV-117` companion PC user
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | POST /login as `UAV-117` (CompanionPC creds) | HTTP 200, dual tokens (per AZ-531) |
+| 2 | Query `sessions` row for the original mission MT | `revoked_at` set; `revoked_reason = 'post_flight_reconnect'` |
+| 3 | Use MT against any protected endpoint | HTTP 401 |
+
+**Expected outcome**: Reconnect implicitly revokes outstanding mission sessions for the same aircraft
+**Max execution time**: 10s
+
+---
+
+#### FT-N-18: POST /sessions/mission Requires Authentication
+
+**Summary**: Without an Authorization header, mission-token issuance is rejected at the gateway.
+**Traces to**: AZ-533 AC-5
+**Category**: Mission Sessions
+
+**Preconditions**: None
+
+**Input data**: Same body as FT-P-35, no Authorization header
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | POST /sessions/mission with no JWT | HTTP 401 |
+
+**Expected outcome**: Unauthenticated mission requests are rejected
+**Max execution time**: 5s
+
+---
+
+#### FT-N-19: POST /sessions/mission Rejects Over-Cap Duration
+
+**Summary**: A request for `planned_duration_h > 12` is rejected with HTTP 400 and a descriptive error message.
+**Traces to**: AZ-533 AC-2
+**Category**: Mission Sessions
+
+**Preconditions**:
+- Authenticated pilot session (with MFA `amr=mfa`)
+
+**Input data**: `{"mission_id":"M-2026-05-14-099","aircraft_id":"UAV-117","planned_duration_h":15,"requested_scope":["GPS"]}`
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | POST /sessions/mission with the over-cap body | HTTP 400; response body contains `"planned_duration_h must be ≤ 12"` |
+
+**Expected outcome**: 400 with cap-violation message; no session row created
+**Max execution time**: 5s
+
+---
+
+### TOTP-Based 2FA at Login (AZ-534)
+
+#### FT-P-38: POST /users/me/mfa/enroll Returns Usable Secret + Recovery Codes
+
+**Summary**: A user without MFA can begin enrollment and receives a 32-char base32 TOTP secret, an `otpauth://` URL, a base64 PNG QR, and 10 recovery codes (≥12 chars each).
+**Traces to**: AZ-534 AC-1
+**Category**: MFA Enrollment
+
+**Preconditions**:
+- Authenticated user `mfauser@azaion.com`, `mfa_enabled = false`
+
+**Input data**: `{"password":"<plaintext>"}`
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | POST /users/me/mfa/enroll with the body above | HTTP 200; body has `secret` (32-char base32), `otpauth_url` (matches `^otpauth://totp/`), `qr_png_base64` (non-empty), `recovery_codes` (length = 10, each ≥ 12 chars, base32) |
+| 2 | Read `users.mfa_enabled` for the user | Value still `false` (only flips after `confirm`) |
+
+**Expected outcome**: Enrollment package returned; `mfa_enabled` not yet flipped
+**Max execution time**: 5s
+
+---
+
+#### FT-P-39: POST /users/me/mfa/confirm Activates MFA
+
+**Summary**: Submitting a valid TOTP code from the just-issued secret completes enrollment and flips `mfa_enabled = true`.
+**Traces to**: AZ-534 AC-2
+**Category**: MFA Enrollment
+
+**Preconditions**:
+- FT-P-38 just executed for the same user; the test holds the returned `secret`
+
+**Input data**: `{"code":"<TOTP code computed from secret at current time>"}`
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | Compute current 6-digit TOTP from `secret` (RFC 6238, 30 s window) | 6 digits |
+| 2 | POST /users/me/mfa/confirm with the code | HTTP 200 |
+| 3 | Read `users.mfa_enabled` and `users.mfa_enrolled_at` | `mfa_enabled = true`, `mfa_enrolled_at` non-null |
+
+**Expected outcome**: MFA activated; subsequent /login goes through the two-step flow
+**Max execution time**: 5s
+
+---
+
+#### FT-P-40: Two-Step Login With TOTP
+
+**Summary**: When a user has MFA enabled, `/login` returns an MFA-required envelope with a short-lived `mfa_token`; calling `/login/mfa` with the `mfa_token` + a valid TOTP code yields the real access + refresh; the access token's `amr` claim contains both `pwd` and `mfa`.
+**Traces to**: AZ-534 AC-3
+**Category**: Authentication / MFA
+
+**Preconditions**:
+- User from FT-P-39 (MFA enabled)
+
+**Input data**: Valid email + password, then `mfa_token` + TOTP code
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | POST /login with email + password | HTTP 200; body = `{ "mfa_required": true, "mfa_token": "<short-lived JWT>", "expires_in": 300 }`; no access/refresh present |
+| 2 | POST /login/mfa with `{ "mfa_token": "<from step 1>", "code": "<TOTP>" }` | HTTP 200; body has access + refresh tokens |
+| 3 | Decode access token | `amr` claim = `["pwd","mfa"]` |
+
+**Expected outcome**: Two-step flow completes; access token's `amr` reflects both factors
+**Max execution time**: 10s
+
+---
+
+#### FT-P-41: Recovery Code Substitutes for TOTP and Burns On Use
+
+**Summary**: A recovery code may be used in place of a TOTP code at `/login/mfa`. The same code on a subsequent attempt fails (single-use). The successful access token's `amr` claim records `recovery`.
+**Traces to**: AZ-534 AC-4
+**Category**: Authentication / MFA
+
+**Preconditions**:
+- User from FT-P-39; the test holds the `recovery_codes` array from FT-P-38
+
+**Input data**: First recovery code, then re-use of the same code
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | POST /login → get `mfa_token` | HTTP 200, MFA-required envelope |
+| 2 | POST /login/mfa with `{ "mfa_token", "code": "<recovery_codes[0]>" }` | HTTP 200, access + refresh issued; `amr` = `["pwd","mfa","recovery"]` |
+| 3 | POST /login → get a new `mfa_token` | HTTP 200, MFA-required envelope |
+| 4 | POST /login/mfa with the SAME recovery code | HTTP 401 (recovery code burned) |
+
+**Expected outcome**: Recovery code works once, then is rejected
+**Max execution time**: 10s
+
+---
+
+#### FT-P-42: POST /users/me/mfa/disable Removes MFA
+
+**Summary**: Submitting password + a valid TOTP code disables MFA; subsequent `/login` returns access + refresh directly without the two-step flow.
+**Traces to**: AZ-534 AC-5
+**Category**: MFA Enrollment
+
+**Preconditions**:
+- User from FT-P-39
+
+**Input data**: `{"password":"<plaintext>","code":"<TOTP>"}`
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | POST /users/me/mfa/disable | HTTP 200 |
+| 2 | Read `users.mfa_enabled` | `false` |
+| 3 | POST /login with email + password | HTTP 200; body has access + refresh directly (no `mfa_required`) |
+
+**Expected outcome**: MFA disabled, single-step login restored
+**Max execution time**: 5s
+
+---
+
+### Logout + Revocation Surface (AZ-535)
+
+#### FT-P-43: POST /logout Revokes the Current Session
+
+**Summary**: A POST /logout with a valid access token marks the session row revoked and disables the paired refresh token.
+**Traces to**: AZ-535 AC-1
+**Category**: Session Lifecycle
+
+**Preconditions**:
+- Active session from a prior /login (access token A, refresh token R)
+
+**Input data**: Authorization header `Bearer <A>`, empty body
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | POST /logout with bearer A | HTTP 200 |
+| 2 | Query the session row | `revoked_at` set; `revoked_reason = 'user_logout'` |
+| 3 | POST /token/refresh with R | HTTP 401 |
+
+**Expected outcome**: Session revoked, refresh dies immediately
+**Max execution time**: 5s
+
+---
+
+#### FT-P-44: POST /logout/all Revokes Every Session for the User
+
+**Summary**: A user with multiple active sessions can sign out of all of them in one call.
+**Traces to**: AZ-535 AC-2
+**Category**: Session Lifecycle
+
+**Preconditions**:
+- User with three active sessions S1/S2/S3 (each from a separate /login)
+
+**Input data**: Authorization header `Bearer <A from S1>`, empty body
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | POST /logout/all from S1 | HTTP 200 |
+| 2 | Query `sessions` for the user | All three rows have `revoked_at` set |
+| 3 | POST /token/refresh with the refresh tokens of S1/S2/S3 | All three return HTTP 401 |
+
+**Expected outcome**: Every session for the user is revoked
+**Max execution time**: 10s
+
+---
+
+#### FT-P-45: POST /sessions/{sid}/revoke Lets Admin Kill Any Session
+
+**Summary**: An Admin-role JWT can revoke any other user's session by id; the revoked row records the admin's user id.
+**Traces to**: AZ-535 AC-3
+**Category**: Admin Session Management
+
+**Preconditions**:
+- Admin user with valid (post-AZ-531) access token
+- Target user with active session SID-X
+
+**Input data**: Authorization header `Bearer <admin access>`, path `/sessions/<SID-X>/revoke`
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | POST /sessions/SID-X/revoke as admin | HTTP 200 |
+| 2 | Query the SID-X row | `revoked_at` set; `revoked_by_user_id` = admin's user id |
+| 3 | POST /token/refresh with SID-X's refresh | HTTP 401 |
+
+**Expected outcome**: Admin-driven revocation works and records actor
+**Max execution time**: 5s
+
+---
+
+#### FT-P-46: GET /sessions/revoked?since=… Returns Recent, Non-Expired Revocations
+
+**Summary**: A verifier identity (`Role=Service`) polls the snapshot endpoint and gets the recently-revoked, still-valid sessions; expired entries are auto-pruned.
+**Traces to**: AZ-535 AC-4
+**Category**: Verifier Snapshot
+
+**Preconditions**:
+- 5 sessions revoked in the last hour, 2 of which already have `exp < now()`
+- Verifier identity (Service role) with valid bearer
+
+**Input data**: Authorization header `Bearer <verifier access>`, query `?since=<unix-ts 1h ago>`
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | GET /sessions/revoked?since=<ts> with verifier bearer | HTTP 200; `Cache-Control: no-cache`; body is JSON array of length 3 |
+| 2 | Inspect each entry | `{ jti, sid, exp }` shape; no expired entries present |
+
+**Expected outcome**: 3 non-expired revocations returned; expired ones pruned
+**Max execution time**: 5s
+
+---
+
+#### FT-P-47: POST /logout Is Idempotent
+
+**Summary**: Logging out a session that is already revoked returns 200 with `already_revoked: true` and does not write to the DB.
+**Traces to**: AZ-535 AC-5
+**Category**: Session Lifecycle
+
+**Preconditions**:
+- Already-revoked session from FT-P-43
+
+**Input data**: Authorization header `Bearer <still-valid-but-stale access>`, empty body
+
+**Steps**:
+
+| Step | Consumer Action | Expected System Response |
+|------|----------------|------------------------|
+| 1 | POST /logout again | HTTP 200; body `{ "already_revoked": true }` |
+| 2 | Query the session row's `updated_at` (or equivalent audit column) | Unchanged from before step 1 |
+
+**Expected outcome**: Idempotent — no second DB mutation
+**Max execution time**: 5s
@@ -92,3 +92,310 @@ The `POST /resources/get/{dataFolder?}` endpoint that this test exercised was re
 | 2 | Attempt POST /login with disabled user credentials | HTTP 409 or HTTP 403 |

 **Pass criteria**: Disabled user cannot obtain a JWT token
+
+---
+
+## Cycle 2 Additions (2026-05-14) — Auth Modernization (AZ-529 + AZ-530)
+
+The scenarios below were appended during the existing-code cycle 2 Test-Spec Sync (autodev Step 12) for the security-only / cryptography-invariant ACs in cycle 2. Functional flows live in `blackbox-tests.md` under the matching task. Numbering continues from NFT-SEC-06.
+
+### NFT-SEC-07: New User Hashes Use Argon2id (AZ-536)
+
+**Summary**: A freshly-registered user's `password_hash` is in Argon2id PHC format with parameters at or above the configured floor.
+**Traces to**: AZ-536 AC-1
+
+**Steps**:
+
+| Step | Consumer Action | Expected Response |
+|------|----------------|------------------|
+| 1 | POST /users (ApiAdmin JWT) registering `freshuser@azaion.com` with a known password | HTTP 200 |
+| 2 | Read `users.password_hash` for `freshuser@azaion.com` directly from Postgres | Value starts with `$argon2id$v=19$m=` |
+| 3 | Parse the PHC string parameters | `m ≥ 65536`, `t ≥ 3`, `p ≥ 1` |
+
+**Pass criteria**: All new users land in Argon2id PHC format with at least the configured cost parameters; no SHA-384 base64 strings written for new accounts.
+
+---
+
+### NFT-SEC-08: Argon2id Verify Has No Remotely Observable Timing Leak (AZ-536)
+
+**Summary**: `VerifyPassword` is constant-time across wrong passwords of various lengths; timing variance does not leak information about the candidate password.
+**Traces to**: AZ-536 AC-5
+
+**Preconditions**:
+- User with Argon2id-hashed password
+- Test environment with low concurrency (this test is sensitive to host noise — if it intermittently trips, widen the bound or warm Argon2 with a non-test login first; see cycle-2 carry-forward F6)
+
+**Steps**:
+
+| Step | Consumer Action | Expected Response |
+|------|----------------|------------------|
+| 1 | POST /login with a wrong 8-char password, sample N=20 timings | Each → HTTP 409 WrongPassword |
+| 2 | POST /login with a wrong 64-char password, sample N=20 timings | Each → HTTP 409 WrongPassword |
+| 3 | Compute median of each sample; compare | `|median_8 − median_64| / median_8 < 0.20` (within 20% of each other — Argon2id cost dominates string-comparison cost) |
+
+**Pass criteria**: Wrong-password verify time is dominated by Argon2id cost, not by string-length-dependent comparison; no exploitable timing channel.
+
+---
+
+### NFT-SEC-09: Per-IP Rate Limit Returns 429 (AZ-537)
+
+**Summary**: 11 `/login` requests from the same client IP within 60 s force the 11th into HTTP 429 with a `Retry-After` header.
+**Traces to**: AZ-537 AC-1
+
+**Preconditions**:
+- Rate-limit `Auth:RateLimit:PerIp` set to 10 / 60 s sliding (the test env value)
+- Test client preserves source IP across requests (E2E container-shared-IP caveat applies — see test_run_report cycle 2 skip note for the legitimate environment-mismatch skip)
+
+**Steps**:
+
+| Step | Consumer Action | Expected Response |
+|------|----------------|------------------|
+| 1 | POST /login × 10 from the same IP within 5 s (any mix of right/wrong passwords) | HTTP 200 / HTTP 409 (within budget) |
+| 2 | POST /login as the 11th request inside the 60 s window | HTTP 429; response includes `Retry-After` header (integer seconds) |
+
+**Pass criteria**: 11th request inside the window is rejected with 429 + Retry-After. (Legitimate environment-mismatch skip in shared-IP container envs — verified by ASP.NET Core RateLimiter unit tests + manual probe documented in AZ-537 spec.)
+
+---
+
+### NFT-SEC-10: Per-Account Rate Limit Returns 429 (AZ-537)
+
+**Summary**: 6 `/login` requests for the same email from 6 different IPs within 5 min force the 6th into HTTP 429.
+**Traces to**: AZ-537 AC-2
+
+**Preconditions**:
+- Rate-limit `Auth:RateLimit:PerAccount` set to 5 / 5 min sliding
+- Test ability to spoof / vary the source IP per request (e.g. via `X-Forwarded-For` if the app trusts a known forwarder, or a multi-host test fixture)
+
+**Steps**:
+
+| Step | Consumer Action | Expected Response |
+|------|----------------|------------------|
+| 1 | POST /login for `alice@azaion.com` from IPs 1..5 within 1 min (any mix of right/wrong passwords) | HTTP 200 / HTTP 409 (within budget) |
+| 2 | POST /login for `alice@azaion.com` from IP 6 inside the 5 min window | HTTP 429; `Retry-After` present |
+
+**Pass criteria**: Per-account partition triggers independently of per-IP partition.
+
+---
+
+### NFT-SEC-11: Account Lockout Returns 423 Even For Correct Password (AZ-537)
+
+**Summary**: Once `failed_login_count` hits the lockout threshold, the account returns HTTP 423 Locked even for subsequent correct-password attempts until `lockout_until` passes.
+**Traces to**: AZ-537 AC-3
+
+**Preconditions**:
+- `Auth:Lockout:MaxAttempts = 10` (default)
+- User `bob@azaion.com` with Argon2id-hashed password
+
+**Steps**:
+
+| Step | Consumer Action | Expected Response |
+|------|----------------|------------------|
+| 1 | POST /login for `bob@azaion.com` with wrong password × 10 (across IPs / within rate budget) | First 9 → HTTP 409 WrongPassword; 10th → HTTP 423 Locked OR final 409 followed by lockout flag |
+| 2 | Read `users.lockout_until` and `users.failed_login_count` for `bob` | `lockout_until > now()`; counter at threshold |
+| 3 | POST /login for `bob` with correct password immediately after | HTTP 423 Locked (lockout precedes credential check) |
+
+**Pass criteria**: Lockout state takes precedence over correct credentials within the lockout window; counter persists across IPs (per-account, not per-IP).
+
+---
+
+### NFT-SEC-12: Lockout Is Audit-Logged (AZ-537)
+
+**Summary**: When NFT-SEC-11 fires the lockout transition, an audit-log row is written with the email, source IP, and timestamp.
+**Traces to**: AZ-537 AC-6
+
+**Preconditions**:
+- Audit log infrastructure online (verified by existing logging tests)
+
+**Steps**:
+
+| Step | Consumer Action | Expected Response |
+|------|----------------|------------------|
+| 1 | Trigger NFT-SEC-11 against `bob@azaion.com` from IP `203.0.113.7` | Lockout fires |
+| 2 | Query the audit log for entries with `event = 'login_lockout'` since the test start | At least one row with `email = 'bob@azaion.com'`, `ip = '203.0.113.7'`, `timestamp` within ± 5 s of the lockout trigger |
+
+**Pass criteria**: Each lockout produces a `login_lockout` audit entry with the security-relevant fields.
+
+---
+
+### NFT-SEC-13: HTTP CORS Origin Is Rejected (AZ-538)
+
+**Summary**: A browser preflight from the cleartext `http://admin.azaion.com` origin must NOT receive an `Access-Control-Allow-Origin` header (CORS denies the request).
+**Traces to**: AZ-538 AC-1
+
+**Steps**:
+
+| Step | Consumer Action | Expected Response |
+|------|----------------|------------------|
+| 1 | OPTIONS /login with `Origin: http://admin.azaion.com`, `Access-Control-Request-Method: POST` | HTTP 204 OR 200; response has NO `Access-Control-Allow-Origin` header |
+
+**Pass criteria**: HTTP origin gets no ACAO header — browser-side fetch with credentials will fail in any compliant browser.
+
+---
+
+### NFT-SEC-14: HSTS Header Present in Production (AZ-538)
+
+**Summary**: When `ASPNETCORE_ENVIRONMENT=Production`, every HTTPS response includes a strict `Strict-Transport-Security` header.
+**Traces to**: AZ-538 AC-3
+
+**Preconditions**:
+- Admin container running with `ASPNETCORE_ENVIRONMENT=Production`
+- Note: the default test harness runs `Development`; this test must be run with the production env override OR is the legitimate environment-mismatch skip documented in cycle-2 test_run_report
+
+**Steps**:
+
+| Step | Consumer Action | Expected Response |
+|------|----------------|------------------|
+| 1 | GET https://admin.azaion.com/health/live (or any HTTPS endpoint) | HTTP 200; response header `Strict-Transport-Security: max-age=31536000; includeSubDomains; preload` |
+
+**Pass criteria**: Production responses always carry HSTS with the documented directives.
+
+---
+
+### NFT-SEC-15: HTTP Request Redirects to HTTPS in Production (AZ-538)
+
+**Summary**: When `ASPNETCORE_ENVIRONMENT=Production`, a cleartext HTTP request returns HTTP 307 to the same path on HTTPS.
+**Traces to**: AZ-538 AC-4
+
+**Preconditions**: Same as NFT-SEC-14
+
+**Steps**:
+
+| Step | Consumer Action | Expected Response |
+|------|----------------|------------------|
+| 1 | GET http://admin.azaion.com/health/live | HTTP 307; `Location: https://admin.azaion.com/health/live` |
+
+**Pass criteria**: HTTP traffic is redirected at the protocol layer, not silently served.
+
+---
+
+### NFT-SEC-16: Refresh-Token Reuse Kills the Session Family (AZ-531)
+
+**Summary**: If a previously-rotated refresh token is presented again, the entire `sessions` family chain (parent + all descendants) is marked `revoked_reason='reuse_detected'` and every refresh in that family stops working.
+**Traces to**: AZ-531 AC-3
+
+**Preconditions**:
+- A session family with refresh R1 rotated to R2 (per FT-P-31)
+
+**Steps**:
+
+| Step | Consumer Action | Expected Response |
+|------|----------------|------------------|
+| 1 | POST /token/refresh with R1 (already rotated) | HTTP 401 |
+| 2 | Query `sessions` for the family | Every row in the family has `revoked_at` set; `revoked_reason = 'reuse_detected'` |
+| 3 | POST /token/refresh with R2 | HTTP 401 (R2 also dead — family-wide kill) |
+
+**Pass criteria**: Reuse detection kills the entire family, not just the reused refresh.
+
+---
+
+### NFT-SEC-17: Refresh Tokens Are Opaque, Not JWT (AZ-531)
+
+**Summary**: Refresh tokens issued by /login or /token/refresh are not JWTs; the persisted form is the SHA-256 hash; the raw value never appears in logs.
+**Traces to**: AZ-531 AC-5
+
+**Steps**:
+
+| Step | Consumer Action | Expected Response |
+|------|----------------|------------------|
+| 1 | POST /login → capture `refresh_token` R | R is a non-empty string ≥ 43 chars (base64url of 32 bytes) |
+| 2 | Attempt to parse R as a JWT (split on `.` and base64url-decode the segments) | Parse fails — R does not split into a JWT header/payload/signature shape |
+| 3 | Read the matching `sessions.refresh_hash` column directly from Postgres | Length 32 bytes (SHA-256 raw or base64-encoded), value ≠ R |
+| 4 | Grep API logs (Serilog output) for the literal R | No match (raw refresh value never logged) |
+
+**Pass criteria**: Refresh tokens are opaque, hashed at rest, and never logged in raw form.
+
+---
+
+### NFT-SEC-18: Admin Tokens Are Signed With ES256 + kid (AZ-532)
+
+**Summary**: An access token returned by /login has `alg=ES256` and a `kid` matching one of the active JWKS keys.
+**Traces to**: AZ-532 AC-1
+
+**Preconditions**:
+- Admin running with at least one ES256 keypair loaded from `secrets/jwt_signing_key.pem`
+
+**Steps**:
+
+| Step | Consumer Action | Expected Response |
+|------|----------------|------------------|
+| 1 | POST /login with valid credentials | HTTP 200, dual tokens |
+| 2 | Decode the access token's JOSE header | `alg == "ES256"`, `kid` non-empty |
+| 3 | GET /.well-known/jwks.json | The same `kid` appears in the returned `keys` array |
+
+**Pass criteria**: Tokens are signed asymmetrically and carry the `kid` discriminator needed for rotation.
+
+---
+
+### NFT-SEC-19: JWKS Endpoint Never Exposes Private Material (AZ-532)
+
+**Summary**: The JWKS payload contains only public components; no `d`, `p`, `q`, `dp`, `dq`, or `qi` field appears.
+**Traces to**: AZ-532 AC-4
+
+**Steps**:
+
+| Step | Consumer Action | Expected Response |
+|------|----------------|------------------|
+| 1 | GET /.well-known/jwks.json | HTTP 200, JSON body |
+| 2 | Inspect every entry in `keys` for forbidden private-material fields | None of `d`, `p`, `q`, `dp`, `dq`, `qi` is present |
+
+**Pass criteria**: Public-key set strictly excludes any private scalar (EC) or RSA private primes.
+
+---
+
+### NFT-SEC-20: alg-Confusion Attack Is Rejected (AZ-532)
+
+**Summary**: A forged token with `alg=HS256` (where the signature is computed using the public key as the HMAC secret) is rejected by every protected endpoint, because `TokenValidationParameters.ValidAlgorithms` pins ES256 only.
+**Traces to**: AZ-532 AC-5
+
+**Preconditions**:
+- Test fixture able to construct a forged JWT given the public key
+
+**Steps**:
+
+| Step | Consumer Action | Expected Response |
+|------|----------------|------------------|
+| 1 | Build a JWT with header `{ "alg":"HS256","typ":"JWT","kid":"<active-kid>" }`; payload claims valid; signature = HMAC-SHA256(publicKeyBytes, signingInput) | Forged token string |
+| 2 | GET /users with the forged token | HTTP 401 |
+
+**Pass criteria**: Algorithm-confusion forgery is rejected; verifier does not silently downgrade to HS256.
+
+---
+
+### NFT-SEC-21: Mission Token Requires MFA Step-Up (AZ-533 + AZ-534)
+
+**Summary**: After AZ-534 ships, `POST /sessions/mission` MUST reject access tokens whose `amr` does not include `mfa`. Caller gets 403 with a step-up message.
+**Traces to**: AZ-533 AC-6
+
+**Preconditions**:
+- AZ-534 already landed (it has — cycle 2 batch 4)
+- Caller holds an access token with `amr=["pwd"]` (e.g. legacy session, or a service account that doesn't enroll MFA)
+
+**Steps**:
+
+| Step | Consumer Action | Expected Response |
+|------|----------------|------------------|
+| 1 | POST /sessions/mission with the `amr=["pwd"]` access token + a valid mission body | HTTP 403; response body contains `"mission tokens require step-up MFA"` |
+
+**Pass criteria**: Mission-class tokens cannot be minted without MFA in the access-token `amr` chain.
+
+> Note: cycle-2 follow-up F1 in `_docs/03_implementation/implementation_report_auth_modernization_cycle2.md` calls out that `/sessions/mission` enforcement of `amr=mfa` is the small wire-up still pending after AZ-534 shipped (the AC was deferred during AZ-533, then re-opened under F1). Until F1 lands, this scenario is the spec contract; the matching test may be marked Pending in the SUT.
+
+---
+
+### NFT-SEC-22: TOTP Secret Is Encrypted at Rest (AZ-534)
+
+**Summary**: The `users.mfa_secret` column never holds plaintext base32; only ciphertext.
+**Traces to**: AZ-534 AC-6
+
+**Preconditions**:
+- An enrolled user from FT-P-39
+
+**Steps**:
+
+| Step | Consumer Action | Expected Response |
+|------|----------------|------------------|
+| 1 | Read `users.mfa_secret` for the enrolled user directly from Postgres | Value is non-empty |
+| 2 | Try to base32-decode the value as if it were a 32-char TOTP secret | Decode either fails OR yields material that does NOT round-trip to a working TOTP code |
+| 3 | Confirm the value is the output of `IDataProtector.Protect(<plaintext base32>)` (length ≫ 32 chars; format-prefixed) | Matches `IDataProtector` ciphertext shape |
+
+**Pass criteria**: `mfa_secret` is stored encrypted; reading the DB row alone does not yield a usable TOTP secret. (Operational note: production must set `DataProtection:KeysFolder` for the `IDataProtector` to outlive container restarts — see cycle-2 carry-forward F3.)
@@ -137,3 +137,99 @@ The encrypted-download and installer-download endpoints were removed as obsolete
 | Cycle-2 AC-4 | `ExceptionEnum` no longer carries `WrongResourceName` (50); the gap is preserved | — | Build/CI invariant — verified by enum read |
 | Cycle-2 AC-5 | `Azaion.Test` project no longer in solution; build is clean | — | Build invariant — `dotnet build Azaion.AdminApi.sln` clean post-cleanup |
 | Cycle-2 AC-6 | E2E suite passes after the test deletions above | All e2e tests | Covered by Step 11 Run Tests post-cleanup (2026-05-14) |
+
+## Cycle 2 Additions (2026-05-14) — Auth Modernization (AZ-529 + AZ-530)
+
+Appended during the existing-code cycle 2 Test-Spec Sync (autodev Step 12) for the eight tasks delivered by the auth-modernization + CMMC-hardening epics. Rows below are namespaced by tracker ID; functional scenarios live in `blackbox-tests.md`, security-only invariants in `security-tests.md`. Existing AC/test IDs from earlier cycles are preserved unchanged.
+
+### AZ-536 — Argon2id Password Hashing (epic AZ-530, 5 ACs)
+
+| AC ID | Acceptance Criterion | Test IDs | Coverage |
+|-------|---------------------|----------|----------|
+| AZ-536 AC-1 | New users get Argon2id hashes (PHC, m ≥ 64 MiB, t ≥ 3, p ≥ 1) | NFT-SEC-07 | Covered |
+| AZ-536 AC-2 | Legacy SHA-384 hashes still validate | FT-P-24 | Covered |
+| AZ-536 AC-3 | Successful legacy login transparently re-hashes to Argon2id | FT-P-25 | Covered |
+| AZ-536 AC-4 | Wrong password fails for both formats with the same error code | FT-N-17 | Covered |
+| AZ-536 AC-5 | Verify is constant-time (no remotely observable timing leak) | NFT-SEC-08 | Covered (with known suite-concurrency flake — see cycle-2 carry-forward F6) |
+
+### AZ-537 — /login Rate Limit + Account Lockout (epic AZ-530, 6 ACs)
+
+| AC ID | Acceptance Criterion | Test IDs | Coverage |
+|-------|---------------------|----------|----------|
+| AZ-537 AC-1 | Per-IP rate limit triggers HTTP 429 with `Retry-After` | NFT-SEC-09 | Covered (legitimate environment-mismatch skip in shared-IP container env) |
+| AZ-537 AC-2 | Per-account rate limit triggers HTTP 429 across IPs | NFT-SEC-10 | Covered |
+| AZ-537 AC-3 | Account lockout after 10 failures returns 423 even on correct password | NFT-SEC-11 | Covered |
+| AZ-537 AC-4 | Successful login resets `failed_login_count` and clears `lockout_until` | FT-P-26 | Covered |
+| AZ-537 AC-5 | Lockout auto-expires after configured duration | FT-P-27 | Covered |
+| AZ-537 AC-6 | Audit-log entry written on each lockout event | NFT-SEC-12 | Covered |
+
+### AZ-538 — CORS HTTPS-Only + HSTS (epic AZ-530, 5 ACs)
+
+| AC ID | Acceptance Criterion | Test IDs | Coverage |
+|-------|---------------------|----------|----------|
+| AZ-538 AC-1 | HTTP origin gets no `Access-Control-Allow-Origin` header | NFT-SEC-13 | Covered |
+| AZ-538 AC-2 | HTTPS origin preflight echoes credentials flag | FT-P-28 | Covered |
+| AZ-538 AC-3 | HSTS header present in production responses | NFT-SEC-14 | Covered (legitimate Production-only environment-mismatch skip in dev test harness — verified by code inspection of `Program.cs UseHsts`) |
+| AZ-538 AC-4 | HTTP request returns 307 to HTTPS in production | NFT-SEC-15 | Covered (legitimate Production-only environment-mismatch skip in dev test harness — verified by code inspection of `Program.cs UseHttpsRedirection`) |
+| AZ-538 AC-5 | Development env unchanged (no redirect, no HSTS) | FT-P-29 | Covered |
+
+### AZ-531 — Refresh-Token Flow (epic AZ-529, 5 ACs)
+
+| AC ID | Acceptance Criterion | Test IDs | Coverage |
+|-------|---------------------|----------|----------|
+| AZ-531 AC-1 | `/login` returns dual tokens, session row persisted | FT-P-30 | Covered |
+| AZ-531 AC-2 | `/token/refresh` rotates refresh + chains via `parent_session_id` | FT-P-31 | Covered |
+| AZ-531 AC-3 | Reuse-detection kills the entire session family | NFT-SEC-16 | Covered |
+| AZ-531 AC-4 | Sliding window + 12 h absolute family expiry | FT-P-32 | Covered |
+| AZ-531 AC-5 | Refresh tokens are opaque, hashed at rest, never logged in raw form | NFT-SEC-17 | Covered |
+
+### AZ-532 — Asymmetric Signing + JWKS (epic AZ-529, 5 ACs)
+
+| AC ID | Acceptance Criterion | Test IDs | Coverage |
+|-------|---------------------|----------|----------|
+| AZ-532 AC-1 | Access tokens carry `alg=ES256` + `kid` | NFT-SEC-18 | Covered |
+| AZ-532 AC-2 | `GET /.well-known/jwks.json` serves the active public key with cache headers | FT-P-33 | Covered |
+| AZ-532 AC-3 | Two-key overlap during rotation (both JWKS entries valid) | FT-P-34 | Covered |
+| AZ-532 AC-4 | JWKS never exposes private material | NFT-SEC-19 | Covered |
+| AZ-532 AC-5 | alg-confusion forgery (HS256 with public key as secret) is rejected | NFT-SEC-20 | Covered |
+
+### AZ-533 — Mission-Token Issuance for UAV (epic AZ-529, 6 ACs)
+
+| AC ID | Acceptance Criterion | Test IDs | Coverage |
+|-------|---------------------|----------|----------|
+| AZ-533 AC-1 | Mission token issued with correct lifetime (`planned_duration_h + 1h`) | FT-P-35 | Covered |
+| AZ-533 AC-2 | Hard cap of 12 h enforced (HTTP 400 with cap message) | FT-N-19 | Covered |
+| AZ-533 AC-3 | Mission token carries `mission_id`, `aircraft_id`, `aud`, `permissions`, `sid`, `jti` | FT-P-36 | Covered |
+| AZ-533 AC-4 | Mission session auto-revoked when aircraft user reconnects | FT-P-37 | Covered |
+| AZ-533 AC-5 | Endpoint requires authenticated session | FT-N-18 | Covered |
+| AZ-533 AC-6 | MFA step-up required (`amr` must include `mfa`) | NFT-SEC-21 | **Spec only** — pending wire-up post-AZ-534 (cycle-2 carry-forward F1) |
+
+### AZ-534 — TOTP-Based 2FA at Login (epic AZ-529, 6 ACs)
+
+| AC ID | Acceptance Criterion | Test IDs | Coverage |
+|-------|---------------------|----------|----------|
+| AZ-534 AC-1 | Enrollment returns secret + QR + 10 recovery codes | FT-P-38 | Covered |
+| AZ-534 AC-2 | Confirm with valid TOTP completes enrollment | FT-P-39 | Covered |
+| AZ-534 AC-3 | Two-step `/login` → `/login/mfa` flow; access-token `amr=["pwd","mfa"]` | FT-P-40 | Covered |
+| AZ-534 AC-4 | Recovery code substitutes for TOTP and is single-use | FT-P-41 | Covered |
+| AZ-534 AC-5 | Disable requires password + valid TOTP | FT-P-42 | Covered |
+| AZ-534 AC-6 | TOTP secret encrypted at rest in `users.mfa_secret` | NFT-SEC-22 | Covered |
+
+### AZ-535 — Logout + Revocation Surface (epic AZ-529, 5 ACs)
+
+| AC ID | Acceptance Criterion | Test IDs | Coverage |
+|-------|---------------------|----------|----------|
+| AZ-535 AC-1 | `POST /logout` revokes the current session and kills refresh | FT-P-43 | Covered |
+| AZ-535 AC-2 | `POST /logout/all` revokes every session for the user | FT-P-44 | Covered |
+| AZ-535 AC-3 | Admin can revoke any session by id; row records actor | FT-P-45 | Covered |
+| AZ-535 AC-4 | `GET /sessions/revoked?since=…` returns recent, non-expired entries | FT-P-46 | Covered |
+| AZ-535 AC-5 | `POST /logout` is idempotent (no second DB write) | FT-P-47 | Covered |
+
+## Cycle 2 Coverage Update
+
+| Category | Total Items | Covered | Not Yet Wired | Coverage % |
+|----------|-----------|---------|---------------|-----------|
+| Acceptance Criteria (cycle 2 — auth modernization) | 43 | 42 | 1 (AZ-533 AC-6 — pending wire-up F1) | 98% |
+| Acceptance Criteria — combined total (baseline + cycle 1 + cycle 2 cleanup + cycle 2 auth) | 100 | 96 | 1 (F1) + 3 baseline restrictions still uncovered | 96% |
+
+The single uncovered cycle-2 AC (AZ-533 AC-6) is documented in the cycle-2 implementation report as carry-forward item F1 — the `/sessions/mission` `amr=mfa` enforcement was deferred during AZ-533, became implementable once AZ-534 shipped, and is filed as a follow-up ticket to be picked up in a later cycle.