22 KiB
22 KiB
NX9-Auth System Architecture Specification
1. System Overview & Executive Summary
NX9-Auth is a lightweight, high-performance, self-hosted Identity and Access Management (IAM) platform written entirely in pure Rust. It provides centralized authentication, fine-grained Role-Based Access Control (RBAC), multi-tenancy, service account management, personal access tokens (PATs), and append-only audit logging.
The system is architected as a modular, stateless HTTP server paired with a zero-JavaScript-framework WebAssembly (WASM) administration user interface. By executing natively on Linux systems without requiring external memory caches (e.g., Redis), JavaScript runtime environments (e.g., Node.js), or third-party web frameworks, NX9-Auth achieves minimal memory consumption, high throughput, zero garbage collection pauses, and operational simplicity.
2. Design Philosophy
NX9-Auth adheres strictly to eight core design tenets:
- Linux-First: Native optimization for Linux environments, systemd process supervision, standard UNIX signals, and POSIX filesystem standards.
- Privacy-First: No external telemetry, phone-home mechanisms, or third-party tracking. All identity records remain strictly under local operator control.
- Self-Hosted & FOSS: Distributed as 100% Free and Open Source Software (FOSS) dual-licensed under Apache 2.0 and MIT.
- Rust-Native Integrity: End-to-end type safety, compile-time memory safety, and thread concurrency guarantees across both server and WebAssembly client binaries.
- Zero Node.js Runtime: No JavaScript runtime dependencies, npm build chains, or node_modules overhead. The frontend is compiled from Rust directly to WebAssembly.
- Minimal Dependencies: Strict audit of external crates to maintain a minimal attack surface, fast compile times, and long-term maintenance stability.
- Operational Simplicity: Single-binary deployment capability with embedded or external SQL databases. Zero mandatory external cache or message broker sidecars.
- Security by Default: OWASP-aligned response headers, memory-hard Argon2id key derivation, BLAKE3 token hashing at rest, non-enumerating error responses, and strict Content Security Policies (CSP).
3. Architectural Principles
The internal architecture is guided by structural design patterns:
- Layer Separation: Downward-only dependency flow (
CLI\rightarrowRuntime\rightarrowApplication\rightarrowHTTP Router\rightarrowServices\rightarrowRepositories\rightarrowDatabase). - Dependency Inversion: Service and handler layers depend on trait abstractions (
UserRepository,SessionRepository) rather than concrete database drivers. - Repository Pattern: Pluggable storage providers (SQLite, PostgreSQL) implementing unified async trait interfaces.
- Configuration over Hardcoding: Fail-fast configuration loading supporting configuration files, environment variable overrides, and CLI flags.
- Stateless HTTP API: Authentication state is encapsulated in cryptographically hashed session cookies or Bearer tokens, eliminating sticky-session server dependencies.
- Fail-Fast Startup: Early validation of configuration paths, database connectivity, and encryption parameters before opening listening sockets.
- Graceful Shutdown: Signal-driven, multi-stage shutdown sequence ensuring background worker completion, audit log flushing, and pool draining.
- Explicit Error Handling: Strongly typed error enumerations (
AppError) mapping internal failures to standard HTTP status codes without leaking sensitive stack traces.
4. Technology Stack
| Component Layer | Technology Choice | Key Function & Architectural Role |
|---|---|---|
| Language Ecosystem | Rust | Core system implementation across server and WebAssembly client. |
| Async Execution | Tokio | Multi-threaded asynchronous I/O, timer management, and task scheduling. |
| HTTP Routing | Axum & Tower | Type-safe REST API routing, request extraction, and middleware pipelines. |
| Database Abstraction | SQLx | Asynchronous, compile-time verified database access for SQLite and PostgreSQL. |
| Password Cryptography | Argon2id | Memory-hard key derivation function for secure password verification. |
| Token Hashing | BLAKE3 | Fast cryptographic hashing for storing session tokens and PATs at rest. |
| Rate Limiting | DashMap | Lock-free, high-concurrency in-memory hash map for tracking IP failure counters. |
| Frontend Framework | Dioxus (WASM) | Declarative, signal-driven WebAssembly UI with virtual DOM reconciliation. |
| WASM HTTP Client | Reqwest (WASM) | WebAssembly HTTP fetch client configured for credentialed API interaction. |
5. Runtime Architecture
5.1 Runtime Core Components
The server runtime (src/runtime/) isolates process lifecycle management from business domain logic:
- Application: The core container holding state, connection pools, state trackers, and worker managers.
- ApplicationBuilder: Assembles configuration, initializes database providers, applies database migrations, and binds the router.
- AtomicRuntimeState: Lock-free atomic state machine enforcing valid lifecycle transitions.
- SignalManager: Asynchronous signal listener intercepting
SIGINTandSIGTERM. - ShutdownCoordinator: Manages prioritized shutdown hooks and completion timeouts.
- WorkerManager: Supervises background asynchronous tasks (e.g., expired session pruning, audit log flushing).
- HookRegistry: Maintains prioritized cleanup routines executed during graceful shutdown.
- RuntimeMetrics: Tracks runtime uptime, active connections, and worker states.
5.2 Deterministic Lifecycle State Machine
stateDiagram-v2
[*] --> Initializing : ApplicationBuilder::build()
Initializing --> Starting : Application::start()
Starting --> Running : TcpListener Bound & axum::serve Awaited
Running --> Draining : SIGINT / SIGTERM Received
Draining --> StoppingWorkers : Background Workers Signaled
StoppingWorkers --> ExecutingHooks : Prioritized Shutdown Hooks Executed
ExecutingHooks --> ClosingResources : Database Connection Pools Drained
ClosingResources --> Stopped : Process Terminates Cleanly
Stopped --> [*]
5.3 Prioritized Shutdown Sequence
When a termination signal is received, the runtime executes hooks sequentially by tier:
- ShutdownPriority::First: Closes HTTP ingress listener and stops receiving new connections.
- ShutdownPriority::Normal: Cancels active background worker loops and awaits inflight jobs.
- ShutdownPriority::Last: Flushes pending audit trails and closes database pool connections.
6. Request Lifecycle & Pipeline Architecture
Every incoming HTTP request traverses a strict layered middleware pipeline:
flowchart TD
Client([Client Request]) --> TCP[Tokio TcpListener]
TCP --> Router[Axum HTTP Router]
subgraph MiddlewarePipeline [" Middleware Pipeline "]
Router --> SecHeaders[Security Headers Middleware\nCSP, Cache-Control, HSTS]
SecHeaders --> TracingMW[Tracing & Request ID Generation]
TracingMW --> Sanitizer[SPA Query String Credential Sanitizer]
end
Sanitizer --> AuthExtractor[AuthUser Extractor\nCookie vs. Bearer Token]
AuthExtractor --> GuardCheck{Endpoint Allowed?}
GuardCheck -- Unauthorized --> ErrResp[HTTP 401 / 403 JSON Response] --> Client
GuardCheck -- Authorized --> Handler[API Route Handler]
Handler --> Service[Domain Service Layer]
Service --> RepoTrait[Repository Trait Interface]
RepoTrait --> DBImpl[SQLite / PostgreSQL Driver]
DBImpl --> DB[(Database Engine)]
DB --> DBImpl --> RepoTrait --> Service --> Handler
Handler --> Response[JSON Response / SPA Assets] --> Client
7. Repository & Database Architecture
7.1 Repository Abstraction Layer
NX9-Auth decouples persistence logic from domain services using Rust traits (async_trait). This guarantees that API handlers remain agnostic of the underlying database engine.
classDiagram
class UserRepository {
<<interface>>
+find_by_id(id) Option~User~
+find_by_username(name) Option~User~
+create(user) User
+update(user) User
+delete(id) bool
}
class SqliteUserRepository {
-SqlitePool pool
+find_by_id(id)
+create(user)
}
class PostgresUserRepository {
-PgPool pool
+find_by_id(id)
+create(user)
}
class AuthService {
-DynUserRepository user_repo
-DynSessionRepository session_repo
+authenticate(credentials)
}
UserRepository <|.. SqliteUserRepository
UserRepository <|.. PostgresUserRepository
AuthService --> UserRepository
7.2 Database Engines & Schema Migrations
- SQLite: Default embedded database provider using WAL (Write-Ahead Logging) mode and busy timeout management for high concurrency.
- PostgreSQL: Production multi-node provider for enterprise environments.
- Migration System: Managed via SQLx embedded migrations executed automatically during startup, guaranteeing schema consistency across upgrades.
8. Authentication Architecture
NX9-Auth supports dual-mode authentication, accommodating both web browser clients (via HttpOnly cookies) and API consumers / SPA applications (via Bearer tokens).
flowchart TD
AuthRequest([Incoming Credentials / Request]) --> RouteType{Request Path?}
RouteType -- POST /api/v1/auth/login --> LoginHandler[Login Handler]
LoginHandler --> VerifyPassword[Verify Password via Argon2id]
VerifyPassword -- Invalid --> TimingMitigation[Execute Dummy Argon2id Delay] --> Return401[Return HTTP 401 Unauthorized]
VerifyPassword -- Valid --> RevokeSessions[Session Fixation Mitigation:\nRevoke Prior Sessions & Tokens]
RevokeSessions --> GenerateTokens[Generate Opaque Tokens:\nst_... and rt_...]
GenerateTokens --> HashTokens[Compute BLAKE3 Hashes for Storage]
HashTokens --> SaveDB[Store Hashes in Database]
SaveDB --> IssueAuth[Issue HttpOnly Cookie + Return Access Token JSON] --> AuthSuccess([Authenticated])
RouteType -- Protected API Route --> ExtractAuth[Extract AuthUser]
ExtractAuth --> CheckCookie{Cookie nx9_session\nPresent?}
CheckCookie -- Yes --> ValidateCookie[BLAKE3 Lookup in Sessions Table]
ValidateCookie -- Valid --> ExtractUserCookie[Find Active User] --> SessionAuth([AuthMethod::Session])
CheckCookie -- No --> CheckHeader{Authorization: Bearer\nHeader Present?}
CheckHeader -- Yes --> TokenPrefix{Token Prefix?}
TokenPrefix -- pat_... --> ValidatePAT[BLAKE3 Lookup in PAT Table] --> ExtractUserPAT[Find Active User] --> PATAuth([AuthMethod::Token])
TokenPrefix -- st_... --> ValidateSession[BLAKE3 Lookup in Sessions Table] --> ExtractUserSession[Find Active User] --> SessionAuth
CheckHeader -- No --> Return401
ValidateCookie -- Invalid --> CheckHeader
ValidatePAT -- Invalid --> Return401
ValidateSession -- Invalid --> Return401
8.1 Key Authentication Mechanisms
- Session Tokens (
st_...): Short-lived opaque session tokens returned on login and stored in HttpOnly cookies or client memory. - Refresh Tokens (
rt_...): Opaque tokens used to issue new session tokens without re-entering primary credentials. - Personal Access Tokens (
pat_...): Long-lived API tokens generated by users for automated integrations, hashed at rest using BLAKE3. - Service Accounts: Non-human identities bound to specific tenants and limited permission scopes for automated workloads.
9. Authorization Model (RBAC)
NX9-Auth implements a hierarchical Role-Based Access Control (RBAC) model:
flowchart LR
User[User / Service Account] --> UserRoles[Assigned Roles]
UserRoles --> RolePermissions[Role Permissions]
RolePermissions --> GlobalPermissions[Effective Permission Set]
Request[API Request Endpoint] --> RequiredPerm[Required Permission Scope]
RequiredPerm --> AccessEvaluator{Permission In Set?}
GlobalPermissions --> AccessEvaluator
AccessEvaluator -- Yes --> Allow[HTTP 200 / Execute Handler]
AccessEvaluator -- No --> Deny[HTTP 403 Forbidden]
Authorization Rules
- Super Admin (
*): Universal access across all tenants and administrative APIs. - Tenant Admin: Administrative authority scoped strictly to resources owned by their tenant.
- Viewer / Standard User: Read-only access or limited domain operation privileges.
- Permission Evaluation: Resolved during the handler phase after successful
AuthUserextraction.
10. Security Architecture
NX9-Auth enforces a defense-in-depth security posture:
┌────────────────────────────────────────────────────────────────────────┐
│ HTTP Response Layer │
│ Strict CSP (script-src 'self' 'wasm-unsafe-eval') | Cache-Control │
│ HSTS | X-Frame-Options: DENY | Referrer-Policy: no-referrer │
└────────────────────────────────────────────────────────────────────────┘
│
┌────────────────────────────────────────────────────────────────────────┐
│ Transport & Sanitization │
│ GET Query Credential Interceptor (HTTP 303 Redirect Sanitizer) │
│ In-Memory Rate Limiting (DashMap Exponential IP Lockout) │
└────────────────────────────────────────────────────────────────────────┘
│
┌────────────────────────────────────────────────────────────────────────┐
│ Cryptographic Storage Layer │
│ Argon2id (m=19456 KiB, t=2, p=1) Password Key Derivation │
│ BLAKE3 Opaque Token Hashing at Rest (Sessions, Refresh, PATs) │
└────────────────────────────────────────────────────────────────────────┘
│
┌────────────────────────────────────────────────────────────────────────┐
│ Audit & Observability │
│ Append-Only Tamper-Evident Audit Logging (actor, target, severity) │
└────────────────────────────────────────────────────────────────────────┘
- Non-Enumerating Authentication Errors: Password failures and non-existent usernames return identical HTTP 401 error payloads and invoke Argon2id execution paths to neutralize timing side-channels.
- Query Parameter Credential Protection: Server-side fallback handlers strip any query strings containing sensitive credentials (
username=,password=) and issue immediate HTTP 303 redirects to clean paths.
11. Multi-Tenancy & Resource Hierarchy
Resources are hierarchically structured to ensure data isolation:
flowchart TD
System[NX9-Auth System] --> TenantA[Tenant A]
System --> TenantB[Tenant B]
TenantA --> UsersA[Users & Service Accounts]
TenantA --> GroupsA[Groups]
TenantA --> AppsA[Applications]
GroupsA --> RolesA[Roles]
AppsA --> ResourcesA[API Resources & Tokens]
TenantB --> UsersB[Users & Service Accounts]
TenantB --> GroupsB[Groups]
TenantB --> AppsB[Applications]
Data Isolation Guarantees
- Every database query for tenant-scoped entities contains explicit
WHERE tenant_id = ?filters. - Service accounts and applications are strictly bound to their parent tenant ID and cannot cross boundaries.
12. Frontend Architecture (WebAssembly SPA)
The administration interface is implemented as a pure WebAssembly Single Page Application (SPA) using Dioxus 0.6:
flowchart TD
Browser[Web Browser] --> IndexHTML[index.html]
IndexHTML --> BootJS[assets/boot.js]
BootJS --> WASMModule[nx9_auth_ui_bg.wasm]
subgraph DioxusWASM [" Dioxus WebAssembly Engine "]
VDOM[Virtual DOM Engine]
SignalState[Signal State Management]
Router[Dioxus Router]
end
WASMModule --> DioxusWASM
subgraph EventSystem [" Dual Event Interception Protocol "]
FormSubmit[Form onsubmit Listener] --> PreventDefault[evt.prevent_default()]
ButtonClick[Button onclick Listener] --> PreventDefault
PreventDefault --> WASMFetch[WASM Reqwest fetch()]
end
DioxusWASM --> EventSystem
WASMFetch -- "Content-Type: application/json\nfetch_credentials_include()" --> BackendAPI[NX9-Auth Axum REST API]
13. Configuration System
NX9-Auth loads configuration using a multi-tiered fallback hierarchy:
1. Explicit CLI Flags (--config /path/to/config.toml)
│
▼
2. Environment Variables (NX9_SERVER__PORT, NX9_DATABASE__URL)
│
▼
3. Local Configuration Files (./config.toml, /etc/nx9-auth/config.toml)
│
▼
4. Compiled Default Fallbacks
Validation & Startup Safeguards
- Configuration loading performs instant fail-fast validation. If database URIs are malformed or TLS configurations are invalid, process execution halts immediately with explicit error logging before binding network ports.
14. Deployment Architecture
NX9-Auth is deployed as a single, self-contained Linux executable:
flowchart LR
Internet([Internet / Clients]) --> ReverseProxy[Reverse Proxy\nNginx / Caddy / Traefik\n(TLS Termination)]
ReverseProxy -- HTTP / Unix Socket --> AppService[NX9-Auth Binary\nSystemd Supervised Service]
AppService <--> SQLite[SQLite Database File\n(WAL Mode)]
AppService <--> Postgres[(PostgreSQL Server)]
Systemd Process Supervision Example (nx9-auth.service)
[Unit]
Description=NX9-Auth Identity & Access Management Server
After=network.target
[Service]
Type=simple
User=nx9-auth
Group=nx9-auth
ExecStart=/usr/local/bin/nx9-auth serve --config /etc/nx9-auth/config.toml
Restart=on-failure
RestartSec=5s
LimitNOFILE=65536
CapabilityBoundingSet=
NoNewPrivileges=true
ProtectSystem=strict
ProtectHome=true
ReadWritePaths=/var/lib/nx9-auth
[Install]
WantedBy=multi-user.target
15. Repository Directory Layout
/
├── Cargo.toml # Primary Cargo workspace manifest
├── Cargo.lock # Dependency lockfile
├── build.rs # Build script for static asset embedding
├── README.md # Project documentation overview
├── LICENSE # Dual license declaration (MIT OR Apache-2.0)
├── LICENSE-MIT # MIT License terms
├── LICENSE-APACHE # Apache 2.0 License terms
├── src/ # Core backend source directory
│ ├── main.rs # Binary entry point and CLI subcommand dispatcher
│ ├── lib.rs # Library root exporting domain modules
│ ├── api/ # Axum REST API handlers and routing table
│ ├── audit/ # Audit trail logging service and DTOs
│ ├── cli/ # Clap CLI subcommand implementations
│ ├── config/ # Configuration file parsing and environment loaders
│ ├── db/ # SQLx database abstraction layers and migrations
│ ├── error/ # Strongly typed application error enumerations
│ ├── identity/ # User, role, group, and tenant management services
│ ├── middleware/ # Security headers, authentication, and logging middlewares
│ ├── runtime/ # Application lifecycle, state machine, and signal hooks
│ └── security/ # Argon2id, BLAKE3, and rate-limiting modules
├── ui/ # WebAssembly Frontend crate (Dioxus 0.6)
│ ├── Cargo.toml # UI package crate manifest
│ ├── index.html # SPA entry point template
│ ├── assets/ # Static styling and JavaScript boot loader
│ └── src/ # Dioxus components, routes, and services
├── tests/ # Integration and end-to-end security test suites
├── scripts/ # Maintenance, build, and release helper scripts
├── deploy/ # Containerization, systemd, and reverse-proxy templates
└── docs/ # Architecture guides, ADRs, and technical specifications
16. Architectural Roadmap & Future Capabilities
The following capabilities represent planned architectural extensions:
- OpenID Connect (OIDC) & OAuth2 Provider: Expanding identity capabilities to act as a full OIDC Authorization Server and Identity Provider (IdP).
- WebAuthn / FIDO2 Passkeys: Native passwordless authentication support using browser WebAuthn APIs.
- Multi-Factor Authentication (MFA): Time-based One-Time Password (TOTP) integration using standard RFC 6238 algorithms.
- SCIM 2.0 & Directory Sync: System for Cross-domain Identity Management (SCIM) for automated user provisioning.
- Observability Exports: OpenTelemetry metrics and tracing exporters for Prometheus and Grafana monitoring stacks.
- High-Availability Clustering: Distributed session cache synchronization across multi-region server nodes.