Update authentication documentation to reflect OAuth/OIDC as primary method
- Update architecture-decisions.md: Change decision to OAuth/OIDC primary, forward auth fallback - Add comprehensive OAuth/OIDC and forward auth flow diagrams - Add decision matrix comparing both authentication methods - Include real examples: Nextcloud/Gitea OAuth configs, whoami forward auth - Update rationale to emphasize OAuth/OIDC security and standards benefits - Update authentication-architecture.md: Align with new OAuth-first approach - Add 'Choosing the Right Pattern' section with clear decision guidance - Swap pattern order: OAuth/OIDC (Pattern 1), Forward Auth (Pattern 2) - Update Example 1: Change Gitea from forward auth to OAuth/OIDC integration - Add emphasis on primary vs fallback methods throughout - Update authentik-deployment-guide.md: Reflect OAuth/OIDC preference - Update overview to mention OAuth2/OIDC provider and forward auth fallback - Add decision guidance to service integration examples - Reorder examples: Nextcloud OAuth (primary), forward auth (fallback) - Clarify forward auth should only be used for services without OAuth support This update ensures all authentication documentation consistently reflects the agreed architectural decision: use OAuth/OIDC when services support it (Nextcloud, Gitea, modern apps), and only use forward auth as a fallback for legacy applications, static sites, or simple tools without OAuth capabilities.
This commit is contained in:
@@ -1,139 +1,9 @@
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# Architecture Decision Records (ADR)
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This document records the significant architectural decisions made in the rick-infra project, particularly focusing on the authentication and infrastructure components.
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## Table of Contents
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- [ADR-001: Native Database Services over Containerized](#adr-001-native-database-services-over-containerized)
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- [ADR-002: Unix Socket IPC Architecture](#adr-002-unix-socket-ipc-architecture)
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- [ADR-003: Podman + systemd Container Orchestration](#adr-003-podman--systemd-container-orchestration)
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- [ADR-004: Forward Authentication Security Model](#adr-004-forward-authentication-security-model)
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- [ADR-005: Rootful Containers with Infrastructure Fact Pattern](#adr-005-rootful-containers-with-infrastructure-fact-pattern)
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This document records the significant architectural decisions made in the rick-infra project.
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---
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## ADR-001: Native Database Services over Containerized
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**Status**: ✅ Accepted
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**Date**: December 2025
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**Deciders**: Infrastructure Team
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**Technical Story**: Need reliable database and cache services for containerized applications with optimal performance and security.
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### Context
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When deploying containerized applications that require database and cache services, there are two primary architectural approaches:
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1. **Containerized Everything**: Deploy databases and cache services as containers
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2. **Native Infrastructure Services**: Use systemd-managed native services for infrastructure, containers for applications
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### Decision
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We will use **native systemd services** for core infrastructure components (PostgreSQL, Valkey/Redis) while using containers only for application services (Authentik, Gitea, etc.).
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### Rationale
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#### Performance Benefits
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- **No Container Overhead**: Native services eliminate container runtime overhead
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```bash
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# Native PostgreSQL: Direct filesystem access
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# Containerized PostgreSQL: Container filesystem layer overhead
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```
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- **Direct System Resources**: Native services access system resources without abstraction layers
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- **Optimized Memory Management**: OS-level memory management without container constraints
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- **Disk I/O Performance**: Direct access to storage without container volume mounting overhead
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#### Security Advantages
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- **Unix Socket Security**: Native services can provide Unix sockets with filesystem-based security
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```bash
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# Native: /var/run/postgresql/.s.PGSQL.5432 (postgres:postgres 0770)
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# Containerized: Requires network exposure or complex socket mounting
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```
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- **Reduced Attack Surface**: No container runtime vulnerabilities for critical infrastructure
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- **OS-Level Security**: Standard system security mechanisms apply directly
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- **Group-Based Access Control**: Simple Unix group membership for service access
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#### Operational Excellence
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- **Standard Tooling**: Familiar systemd service management
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```bash
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systemctl status postgresql
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journalctl -u postgresql -f
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systemctl restart postgresql
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```
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- **Package Management**: Standard OS package updates and security patches
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- **Backup Integration**: Native backup tools work seamlessly
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```bash
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pg_dump -h /var/run/postgresql authentik > backup.sql
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```
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- **Monitoring**: Standard system monitoring tools apply directly
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#### Reliability
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- **systemd Integration**: Robust service lifecycle management
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```ini
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[Unit]
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Description=PostgreSQL database server
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After=network.target
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[Service]
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Type=forking
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Restart=always
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RestartSec=5
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```
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- **Resource Isolation**: systemd provides resource isolation without container overhead
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- **Proven Architecture**: Battle-tested approach used by major infrastructure providers
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### Consequences
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#### Positive
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- **Performance**: 15-25% better database performance in benchmarks
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- **Security**: Eliminated network-based database attacks via Unix sockets
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- **Operations**: Simplified backup, monitoring, and maintenance procedures
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- **Resource Usage**: Lower memory and CPU overhead
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- **Reliability**: More predictable service behavior
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#### Negative
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- **Containerization Purity**: Not a "pure" containerized environment
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- **Portability**: Slightly less portable than full-container approach
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- **Learning Curve**: Team needs to understand both systemd and container management
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#### Neutral
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- **Complexity**: Different but not necessarily more complex than container orchestration
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- **Tooling**: Different toolset but equally capable
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### Implementation Notes
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```yaml
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# Infrastructure services (native systemd)
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- postgresql # Native database service
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- valkey # Native cache service
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- caddy # Native reverse proxy
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- podman # Container runtime
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# Application services (containerized)
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- authentik # Authentication service
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- gitea # Git service
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```
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### Alternatives Considered
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1. **Full Containerization**: Rejected due to performance and operational complexity
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2. **Mixed with Docker**: Rejected in favor of Podman for security benefits
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3. **VM-based Infrastructure**: Rejected due to resource overhead
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---
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## ADR-002: Unix Socket IPC Architecture
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**Status**: ✅ Accepted
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**Date**: December 2025
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**Deciders**: Infrastructure Team
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**Technical Story**: Secure and performant communication between containerized applications and native infrastructure services.
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## Unix Socket IPC Architecture
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### Context
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@@ -141,11 +11,10 @@ Containerized applications need to communicate with database and cache services.
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1. **Network TCP/IP**: Standard network protocols
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2. **Unix Domain Sockets**: Filesystem-based IPC
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3. **Shared Memory**: Direct memory sharing (complex)
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### Decision
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We will use **Unix domain sockets** for all communication between containerized applications and infrastructure services.
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We will use **Unix domain sockets** for all communication between applications and infrastructure services.
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### Rationale
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@@ -269,10 +138,6 @@ podman exec authentik-server id
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## ADR-003: Podman + systemd Container Orchestration
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**Status**: ✅ Accepted
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**Date**: December 2025
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**Updated**: December 2025 (System-level deployment pattern)
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**Deciders**: Infrastructure Team
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**Technical Story**: Container orchestration solution for secure application deployment with systemd integration.
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### Context
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@@ -493,12 +358,9 @@ ps aux | grep authentik-server | head -1 | awk '{print $2}' | \
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---
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## ADR-004: Forward Authentication Security Model
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## OAuth/OIDC and Forward Authentication Security Model
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**Status**: ✅ Accepted
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**Date**: December 2025
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**Deciders**: Infrastructure Team
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**Technical Story**: Centralized authentication and authorization for multiple services without modifying existing applications.
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**Technical Story**: Centralized authentication and authorization for multiple services using industry-standard OAuth2/OIDC protocols where supported, with forward authentication as a fallback.
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### Context
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@@ -506,53 +368,122 @@ Authentication strategies for multiple services:
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1. **Per-Service Authentication**: Each service handles its own authentication
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2. **Shared Database**: Services share authentication database
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3. **Forward Authentication**: Reverse proxy handles authentication
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4. **OAuth2/OIDC Integration**: Services implement OAuth2 clients
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3. **OAuth2/OIDC Integration**: Services implement standard OAuth2/OIDC clients
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4. **Forward Authentication**: Reverse proxy handles authentication for services without OAuth support
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### Decision
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We will use **forward authentication** with Caddy reverse proxy and Authentik authentication server as the primary authentication model.
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We will use **OAuth2/OIDC integration** as the primary authentication method for services that support it, and **forward authentication** for services that do not support native OAuth2/OIDC integration.
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### Rationale
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#### Security Benefits
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#### OAuth/OIDC as Primary Method
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- **Single Point of Control**: Centralized authentication policy
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**Security Benefits**:
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- **Standard Protocol**: Industry-standard authentication flow (RFC 6749, RFC 7636)
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- **Token-Based Security**: Secure JWT tokens with cryptographic signatures
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- **Proper Session Management**: Native application session handling with refresh tokens
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- **Scope-Based Authorization**: Fine-grained permission control via OAuth scopes
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- **PKCE Support**: Protection against authorization code interception attacks
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**Integration Benefits**:
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- **Native Support**: Applications designed for OAuth/OIDC work seamlessly
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- **Better UX**: Proper redirect flows, logout handling, and token refresh
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- **API Access**: OAuth tokens enable secure API integrations
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- **Standard Claims**: OpenID Connect user info endpoint provides standardized user data
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- **Multi-Application SSO**: Proper single sign-on with token sharing
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**Examples**: Nextcloud, Gitea, Grafana, many modern applications
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#### Forward Auth as Fallback
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**Use Cases**:
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- Services without OAuth/OIDC support
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- Legacy applications that cannot be modified
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- Static sites requiring authentication
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- Simple internal tools
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**Security Benefits**:
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- **Zero Application Changes**: Protect existing services without modification
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- **Consistent Security**: Same security model across all services
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- **Session Management**: Centralized session handling and timeouts
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- **Multi-Factor Authentication**: MFA applied consistently across services
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- **Header-Based Identity**: Simple identity propagation to backend
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- **Transparent Protection**: Services receive pre-authenticated requests
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#### Operational Advantages
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**Limitations**:
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- **Non-Standard**: Not using industry-standard authentication protocols
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- **Proxy Dependency**: All requests must flow through authenticating proxy
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- **Limited Logout**: Complex logout scenarios across services
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- **Header Trust**: Backend must trust proxy-provided headers
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- **Simplified Deployment**: No per-service authentication setup
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#### Shared Benefits (Both Methods)
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- **Single Point of Control**: Centralized authentication policy via Authentik
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- **Consistent Security**: Same authentication provider across all services
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- **Multi-Factor Authentication**: MFA applied consistently via Authentik
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- **Audit Trail**: Centralized authentication logging
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- **Policy Management**: Single place to manage access policies
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- **User Management**: One system for all user administration
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- **Service Independence**: Services focus on business logic
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#### Integration Benefits
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- **Transparent to Applications**: Services receive authenticated requests
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- **Header-Based Identity**: Simple identity propagation
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```http
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Remote-User: john.doe
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Remote-Name: John Doe
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Remote-Email: john.doe@company.com
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Remote-Groups: admins,developers
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```
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- **Gradual Migration**: Can protect services incrementally
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- **Fallback Support**: Can coexist with service-native authentication
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### Implementation Architecture
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#### OAuth/OIDC Flow (Primary Method)
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```
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┌─────────────┐ ┌─────────────┐ ┌─────────────┐
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│ User │ │ Service │ │ Authentik │
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│ │ │ (OAuth App) │ │ (IdP) │
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└──────┬──────┘ └──────┬──────┘ └──────┬──────┘
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│ │ │
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│ Access Service │ │
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│─────────────────▶│ │
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│ │ │
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│ │ No session │
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│ 302 → OAuth │ │
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│◀─────────────────│ │
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│ │ │
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│ GET /authorize?client_id=...&redirect_uri=...
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│──────────────────────────────────────▶│
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│ │ │
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│ Login form (if not authenticated) │
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│◀────────────────────────────────────│
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│ │ │
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│ Credentials │ │
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│─────────────────────────────────────▶│
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│ │ │
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│ 302 → callback?code=AUTH_CODE │
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│◀────────────────────────────────────│
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│ │ │
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│ GET /callback?code=AUTH_CODE │
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│─────────────────▶│ │
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│ │ │
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│ │ POST /token │
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│ │ code=AUTH_CODE │
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│ │─────────────────▶│
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│ │ │
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│ │ access_token │
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│ │ id_token (JWT) │
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│ │◀─────────────────│
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│ │ │
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│ Set-Cookie │ GET /userinfo │
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│ 302 → /dashboard │─────────────────▶│
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│◀─────────────────│ │
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│ │ User claims │
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│ │◀─────────────────│
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│ │ │
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│ GET /dashboard │ │
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│─────────────────▶│ │
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│ │ │
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||||
│ Dashboard │ │
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│◀─────────────────│ │
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```
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#### Forward Auth Flow (Fallback Method)
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||||
|
||||
```
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┌─────────────┐ ┌─────────────┐ ┌─────────────┐ ┌─────────────┐
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│ User │ │ Caddy │ │ Authentik │ │ Service │
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│ │ │ (Proxy) │ │ (Auth) │ │ (Backend) │
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│ │ │ (Proxy) │ │ (Forward) │ │ (Backend) │
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└──────┬──────┘ └──────┬──────┘ └──────┬──────┘ └──────┬──────┘
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||||
│ │ │ │
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||||
│ GET /dashboard │ │ │
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||||
│ GET / │ │ │
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||||
│─────────────────▶│ │ │
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||||
│ │ │ │
|
||||
│ │ Forward Auth │ │
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||||
@@ -561,19 +492,19 @@ We will use **forward authentication** with Caddy reverse proxy and Authentik au
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│ │ 401 Unauthorized │ │
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||||
│ │◀─────────────────│ │
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||||
│ │ │ │
|
||||
│ 302 → /auth/login│ │ │
|
||||
│ 302 → /auth │ │ │
|
||||
│◀─────────────────│ │ │
|
||||
│ │ │ │
|
||||
│ Login form │ │ │
|
||||
│─────────────────▶│─────────────────▶│ │
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||||
│──────────────────────────────────────▶│ │
|
||||
│ │ │ │
|
||||
│ Credentials │ │ │
|
||||
│─────────────────▶│─────────────────▶│ │
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||||
│──────────────────────────────────────▶│ │
|
||||
│ │ │ │
|
||||
│ Set-Cookie │ │ │
|
||||
│◀─────────────────│◀─────────────────│ │
|
||||
│◀──────────────────────────────────────│ │
|
||||
│ │ │ │
|
||||
│ GET /dashboard │ │ │
|
||||
│ GET / │ │ │
|
||||
│─────────────────▶│ │ │
|
||||
│ │ │ │
|
||||
│ │ Forward Auth │ │
|
||||
@@ -582,21 +513,93 @@ We will use **forward authentication** with Caddy reverse proxy and Authentik au
|
||||
│ │ 200 + Headers │ │
|
||||
│ │◀─────────────────│ │
|
||||
│ │ │ │
|
||||
│ │ GET /dashboard + Auth Headers │
|
||||
│ │ Proxy + Headers │ │
|
||||
│ │─────────────────────────────────────▶│
|
||||
│ │ │
|
||||
│ │ Dashboard Content │
|
||||
│ │ │ │
|
||||
│ │ Response │ │
|
||||
│ │◀─────────────────────────────────────│
|
||||
│ │ │
|
||||
│ Dashboard │ │
|
||||
│◀─────────────────│ │
|
||||
│ │ │ │
|
||||
│ Content │ │ │
|
||||
│◀─────────────────│ │ │
|
||||
```
|
||||
|
||||
### Caddy Configuration
|
||||
### OAuth/OIDC Configuration Examples
|
||||
|
||||
#### Nextcloud OAuth Configuration
|
||||
|
||||
```php
|
||||
// Nextcloud config.php
|
||||
'oidc_login_provider_url' => 'https://auth.jnss.me/application/o/nextcloud/',
|
||||
'oidc_login_client_id' => 'nextcloud-client-id',
|
||||
'oidc_login_client_secret' => 'secret-from-authentik',
|
||||
'oidc_login_auto_redirect' => true,
|
||||
'oidc_login_end_session_redirect' => true,
|
||||
'oidc_login_button_text' => 'Login with SSO',
|
||||
'oidc_login_hide_password_form' => true,
|
||||
'oidc_login_use_id_token' => true,
|
||||
'oidc_login_attributes' => [
|
||||
'id' => 'preferred_username',
|
||||
'name' => 'name',
|
||||
'mail' => 'email',
|
||||
'groups' => 'groups',
|
||||
],
|
||||
'oidc_login_default_group' => 'users',
|
||||
'oidc_login_use_external_storage' => false,
|
||||
'oidc_login_scope' => 'openid profile email groups',
|
||||
'oidc_login_proxy_ldap' => false,
|
||||
'oidc_login_disable_registration' => false,
|
||||
'oidc_login_redir_fallback' => true,
|
||||
'oidc_login_tls_verify' => true,
|
||||
```
|
||||
|
||||
#### Gitea OAuth Configuration
|
||||
|
||||
```ini
|
||||
# Gitea app.ini
|
||||
[openid]
|
||||
ENABLE_OPENID_SIGNIN = false
|
||||
ENABLE_OPENID_SIGNUP = false
|
||||
|
||||
[oauth2_client]
|
||||
REGISTER_EMAIL_CONFIRM = false
|
||||
OPENID_CONNECT_SCOPES = openid email profile groups
|
||||
ENABLE_AUTO_REGISTRATION = true
|
||||
USERNAME = preferred_username
|
||||
EMAIL = email
|
||||
ACCOUNT_LINKING = auto
|
||||
```
|
||||
|
||||
**Authentik Provider Configuration** (Gitea):
|
||||
- Provider Type: OAuth2/OpenID Provider
|
||||
- Client ID: `gitea`
|
||||
- Client Secret: Generated by Authentik
|
||||
- Redirect URIs: `https://git.jnss.me/user/oauth2/Authentik/callback`
|
||||
- Scopes: `openid`, `profile`, `email`, `groups`
|
||||
|
||||
#### Authentik OAuth2 Provider Settings
|
||||
|
||||
```yaml
|
||||
# OAuth2/OIDC Provider configuration in Authentik
|
||||
name: "Nextcloud OAuth Provider"
|
||||
authorization_flow: "default-authorization-flow"
|
||||
client_type: "confidential"
|
||||
client_id: "nextcloud-client-id"
|
||||
redirect_uris: "https://cloud.jnss.me/apps/oidc_login/oidc"
|
||||
signing_key: "authentik-default-key"
|
||||
property_mappings:
|
||||
- "authentik default OAuth Mapping: OpenID 'openid'"
|
||||
- "authentik default OAuth Mapping: OpenID 'email'"
|
||||
- "authentik default OAuth Mapping: OpenID 'profile'"
|
||||
- "Custom: Groups" # Maps user groups to 'groups' claim
|
||||
```
|
||||
|
||||
### Forward Auth Configuration Examples
|
||||
|
||||
#### Caddy Configuration for Forward Auth
|
||||
|
||||
```caddyfile
|
||||
# Service protection template
|
||||
dashboard.jnss.me {
|
||||
# whoami service with forward authentication
|
||||
whoami.jnss.me {
|
||||
# Forward authentication to Authentik
|
||||
forward_auth https://auth.jnss.me {
|
||||
uri /outpost.goauthentik.io/auth/caddy
|
||||
@@ -608,120 +611,194 @@ dashboard.jnss.me {
|
||||
}
|
||||
```
|
||||
|
||||
### Service Integration
|
||||
#### Authentik Proxy Provider Configuration
|
||||
|
||||
```yaml
|
||||
# Authentik Proxy Provider for forward auth
|
||||
name: "Whoami Forward Auth"
|
||||
type: "proxy"
|
||||
authorization_flow: "default-authorization-flow"
|
||||
external_host: "https://whoami.jnss.me"
|
||||
internal_host: "http://localhost:8080"
|
||||
skip_path_regex: "^/(health|metrics).*"
|
||||
mode: "forward_single" # Single application mode
|
||||
```
|
||||
|
||||
#### Service Integration (Forward Auth)
|
||||
|
||||
Services receive authentication information via HTTP headers:
|
||||
|
||||
```python
|
||||
# Example service code (Python Flask)
|
||||
@app.route('/dashboard')
|
||||
def dashboard():
|
||||
@app.route('/')
|
||||
def index():
|
||||
username = request.headers.get('Remote-User')
|
||||
name = request.headers.get('Remote-Name')
|
||||
email = request.headers.get('Remote-Email')
|
||||
groups = request.headers.get('Remote-Groups', '').split(',')
|
||||
|
||||
if 'admins' in groups:
|
||||
# Admin functionality
|
||||
pass
|
||||
|
||||
return render_template('dashboard.html',
|
||||
return render_template('index.html',
|
||||
username=username,
|
||||
name=name)
|
||||
```
|
||||
|
||||
### Authentik Provider Configuration
|
||||
|
||||
```yaml
|
||||
# Authentik Proxy Provider configuration
|
||||
name: "Service Forward Auth"
|
||||
authorization_flow: "default-authorization-flow"
|
||||
external_host: "https://service.jnss.me"
|
||||
internal_host: "http://localhost:8080"
|
||||
skip_path_regex: "^/(health|metrics|static).*"
|
||||
name=name,
|
||||
email=email,
|
||||
groups=groups)
|
||||
```
|
||||
|
||||
### Authorization Policies
|
||||
|
||||
Both OAuth and Forward Auth support Authentik authorization policies:
|
||||
|
||||
```yaml
|
||||
# Example authorization policy in Authentik
|
||||
policy_bindings:
|
||||
- policy: "group_admins_only"
|
||||
target: "service_dashboard"
|
||||
target: "nextcloud_oauth_provider"
|
||||
order: 0
|
||||
|
||||
- policy: "deny_external_ips"
|
||||
target: "admin_endpoints"
|
||||
- policy: "require_mfa"
|
||||
target: "gitea_oauth_provider"
|
||||
order: 1
|
||||
|
||||
- policy: "internal_network_only"
|
||||
target: "whoami_proxy_provider"
|
||||
order: 0
|
||||
```
|
||||
|
||||
### Decision Matrix: OAuth/OIDC vs Forward Auth
|
||||
|
||||
| Criteria | OAuth/OIDC | Forward Auth |
|
||||
|----------|-----------|-------------|
|
||||
| **Application Support** | Requires native OAuth/OIDC support | Any application |
|
||||
| **Protocol Standard** | Industry standard (RFC 6749, 7636) | Proprietary/custom |
|
||||
| **Token Management** | Native refresh tokens, proper expiry | Session-based only |
|
||||
| **Logout Handling** | Proper logout flow | Complex, proxy-dependent |
|
||||
| **API Access** | Full API support via tokens | Header-only |
|
||||
| **Implementation Effort** | Configure OAuth settings | Zero app changes |
|
||||
| **User Experience** | Standard OAuth redirects | Transparent |
|
||||
| **Security Model** | Token-based with scopes | Header trust model |
|
||||
| **When to Use** | **Nextcloud, Gitea, modern apps** | **Static sites, legacy apps, whoami** |
|
||||
|
||||
### Consequences
|
||||
|
||||
#### Positive
|
||||
|
||||
- **Security**: Consistent, centralized authentication and authorization
|
||||
- **Simplicity**: No application changes required for protection
|
||||
- **Flexibility**: Fine-grained access control through Authentik policies
|
||||
- **Auditability**: Centralized authentication logging
|
||||
- **User Experience**: Single sign-on across all services
|
||||
- **Standards Compliance**: OAuth/OIDC uses industry-standard protocols
|
||||
- **Security**: Multiple authentication options with appropriate security models
|
||||
- **Flexibility**: Right tool for each service (OAuth when possible, forward auth when needed)
|
||||
- **Auditability**: Centralized authentication logging via Authentik
|
||||
- **User Experience**: Proper SSO across all services
|
||||
- **Token Security**: OAuth provides secure token refresh and scope management
|
||||
- **Graceful Degradation**: Forward auth available for services without OAuth support
|
||||
|
||||
#### Negative
|
||||
|
||||
- **Single Point of Failure**: Authentication system failure affects all services
|
||||
- **Performance**: Additional hop for authentication checks
|
||||
- **Complexity**: Additional component in the request path
|
||||
- **Complexity**: Need to understand two authentication methods
|
||||
- **Configuration Overhead**: OAuth requires per-service configuration
|
||||
- **Single Point of Failure**: Authentik failure affects all services
|
||||
- **Learning Curve**: Team must understand OAuth flows and forward auth model
|
||||
|
||||
#### Mitigation Strategies
|
||||
|
||||
- **High Availability**: Robust deployment and monitoring of auth components
|
||||
- **Caching**: Session caching to reduce authentication overhead
|
||||
- **Fallback**: Emergency bypass procedures for critical services
|
||||
- **Monitoring**: Comprehensive monitoring of authentication flow
|
||||
- **Documentation**: Clear decision guide for choosing OAuth vs forward auth
|
||||
- **Templates**: Reusable OAuth configuration templates for common services
|
||||
- **High Availability**: Robust deployment and monitoring of Authentik
|
||||
- **Monitoring**: Comprehensive monitoring of both authentication flows
|
||||
- **Testing**: Automated tests for authentication flows
|
||||
|
||||
### Security Considerations
|
||||
|
||||
#### Session Security
|
||||
#### OAuth/OIDC Security
|
||||
|
||||
```yaml
|
||||
# Authentik session settings
|
||||
session_cookie_age: 3600 # 1 hour
|
||||
session_cookie_secure: true
|
||||
session_cookie_samesite: "Strict"
|
||||
session_remember_me: false
|
||||
# Authentik OAuth2 Provider security settings
|
||||
authorization_code_validity: 60 # 1 minute
|
||||
access_code_validity: 3600 # 1 hour
|
||||
refresh_code_validity: 2592000 # 30 days
|
||||
include_claims_in_id_token: true
|
||||
signing_key: "authentik-default-key"
|
||||
sub_mode: "hashed_user_id"
|
||||
issuer_mode: "per_provider"
|
||||
```
|
||||
|
||||
**Best Practices**:
|
||||
- Use PKCE for all OAuth flows (protection against interception)
|
||||
- Implement proper token rotation (refresh tokens expire and rotate)
|
||||
- Validate `aud` (audience) and `iss` (issuer) claims in JWT tokens
|
||||
- Use short-lived access tokens (1 hour)
|
||||
- Store client secrets securely (Ansible Vault)
|
||||
|
||||
#### Forward Auth Security
|
||||
|
||||
```yaml
|
||||
# Authentik Proxy Provider security settings
|
||||
token_validity: 3600 # 1 hour session
|
||||
cookie_domain: ".jnss.me"
|
||||
skip_path_regex: "^/(health|metrics|static).*"
|
||||
```
|
||||
|
||||
**Best Practices**:
|
||||
- Trust only Authentik-provided headers
|
||||
- Validate `Remote-User` header exists before granting access
|
||||
- Use HTTPS for all forward auth endpoints
|
||||
- Implement proper session timeouts
|
||||
- Strip user-provided authentication headers at proxy
|
||||
|
||||
#### Access Control
|
||||
|
||||
- **Group-Based Authorization**: Users assigned to groups, groups to applications
|
||||
- **Time-Based Access**: Temporary access grants
|
||||
- **IP-Based Restrictions**: Geographic or network-based access control
|
||||
- **Policy Engine**: Authentik policies for fine-grained access control
|
||||
- **MFA Requirements**: Multi-factor authentication for sensitive services
|
||||
- **IP-Based Restrictions**: Geographic or network-based access control
|
||||
- **Time-Based Access**: Temporary access grants via policies
|
||||
|
||||
#### Audit Logging
|
||||
|
||||
```json
|
||||
{
|
||||
"timestamp": "2025-12-11T17:52:31Z",
|
||||
"event": "authentication_success",
|
||||
"timestamp": "2025-12-15T10:30:00Z",
|
||||
"event": "oauth_authorization",
|
||||
"user": "john.doe",
|
||||
"service": "dashboard.jnss.me",
|
||||
"application": "nextcloud",
|
||||
"scopes": ["openid", "email", "profile", "groups"],
|
||||
"ip": "192.168.1.100",
|
||||
"user_agent": "Mozilla/5.0..."
|
||||
}
|
||||
```
|
||||
|
||||
### Alternative Models Supported
|
||||
### Implementation Examples by Service Type
|
||||
|
||||
While forward auth is primary, we also support:
|
||||
#### OAuth/OIDC Services (Primary Method)
|
||||
|
||||
1. **OAuth2/OIDC Integration**: For applications that can implement OAuth2
|
||||
2. **API Key Authentication**: For service-to-service communication
|
||||
3. **Service-Native Auth**: For legacy applications that cannot be easily protected
|
||||
**Nextcloud**:
|
||||
```caddyfile
|
||||
cloud.jnss.me {
|
||||
reverse_proxy localhost:8080
|
||||
}
|
||||
# OAuth configured within Nextcloud application
|
||||
```
|
||||
|
||||
### Implementation Examples
|
||||
**Gitea**:
|
||||
```caddyfile
|
||||
git.jnss.me {
|
||||
reverse_proxy localhost:3000
|
||||
}
|
||||
# OAuth configured within Gitea application settings
|
||||
```
|
||||
|
||||
#### Protecting a Static Site
|
||||
#### Forward Auth Services (Fallback Method)
|
||||
|
||||
**Whoami (test/demo service)**:
|
||||
```caddyfile
|
||||
whoami.jnss.me {
|
||||
forward_auth https://auth.jnss.me {
|
||||
uri /outpost.goauthentik.io/auth/caddy
|
||||
copy_headers Remote-User Remote-Name Remote-Email Remote-Groups
|
||||
}
|
||||
reverse_proxy localhost:8080
|
||||
}
|
||||
```
|
||||
|
||||
**Static Documentation Site**:
|
||||
```caddyfile
|
||||
docs.jnss.me {
|
||||
forward_auth https://auth.jnss.me {
|
||||
@@ -734,33 +811,44 @@ docs.jnss.me {
|
||||
}
|
||||
```
|
||||
|
||||
#### Protecting an API
|
||||
|
||||
**Internal API (no OAuth support)**:
|
||||
```caddyfile
|
||||
api.jnss.me {
|
||||
forward_auth https://auth.jnss.me {
|
||||
uri /outpost.goauthentik.io/auth/caddy
|
||||
copy_headers Remote-User Remote-Email Remote-Groups
|
||||
}
|
||||
|
||||
reverse_proxy localhost:3000
|
||||
}
|
||||
```
|
||||
|
||||
#### Public Endpoints with Selective Protection
|
||||
#### Selective Protection (Public + Protected Paths)
|
||||
|
||||
```caddyfile
|
||||
app.jnss.me {
|
||||
# Public endpoints (no auth)
|
||||
# Public endpoints (no auth required)
|
||||
handle /health {
|
||||
reverse_proxy localhost:8080
|
||||
}
|
||||
|
||||
handle /metrics {
|
||||
reverse_proxy localhost:8080
|
||||
}
|
||||
|
||||
handle /public/* {
|
||||
reverse_proxy localhost:8080
|
||||
}
|
||||
|
||||
# Protected endpoints
|
||||
# Protected endpoints (forward auth)
|
||||
handle /admin/* {
|
||||
forward_auth https://auth.jnss.me {
|
||||
uri /outpost.goauthentik.io/auth/caddy
|
||||
copy_headers Remote-User Remote-Groups
|
||||
}
|
||||
reverse_proxy localhost:8080
|
||||
}
|
||||
|
||||
# Default: protected
|
||||
handle {
|
||||
forward_auth https://auth.jnss.me {
|
||||
uri /outpost.goauthentik.io/auth/caddy
|
||||
@@ -773,18 +861,17 @@ app.jnss.me {
|
||||
|
||||
### Alternatives Considered
|
||||
|
||||
1. **OAuth2 Only**: Rejected due to application modification requirements
|
||||
2. **Shared Database**: Rejected due to tight coupling between services
|
||||
3. **VPN-Based Access**: Rejected due to operational complexity for web services
|
||||
4. **Per-Service Authentication**: Rejected due to management overhead
|
||||
1. **OAuth2/OIDC Only**: Rejected because many services don't support OAuth natively
|
||||
2. **Forward Auth Only**: Rejected because it doesn't leverage native OAuth support in modern apps
|
||||
3. **Per-Service Authentication**: Rejected due to management overhead and inconsistent security
|
||||
4. **Shared Database**: Rejected due to tight coupling between services
|
||||
5. **VPN-Based Access**: Rejected due to operational complexity for web services
|
||||
6. **SAML**: Rejected in favor of modern OAuth2/OIDC standards
|
||||
|
||||
---
|
||||
|
||||
## ADR-005: Rootful Containers with Infrastructure Fact Pattern
|
||||
## Rootful Containers with Infrastructure Fact Pattern
|
||||
|
||||
**Status**: ✅ Accepted
|
||||
**Date**: December 2025
|
||||
**Deciders**: Infrastructure Team
|
||||
**Technical Story**: Enable containerized applications to access native infrastructure services (PostgreSQL, Valkey) via Unix sockets with group-based permissions.
|
||||
|
||||
### Context
|
||||
@@ -1038,25 +1125,5 @@ curl -I http://127.0.0.1:9000/
|
||||
1. **Rootless with user namespace** - Discarded due to GID remapping breaking group-based socket access
|
||||
2. **TCP-only connections** - Rejected to maintain Unix socket security and performance benefits
|
||||
3. **Hardcoded GIDs** - Rejected for portability; facts provide dynamic resolution
|
||||
4. **Directory permissions (777)** - Rejected for security; group-based access more restrictive
|
||||
|
||||
4. **Directory permissions (777)** - Rejected for security; group-based access more restrictive. This is then later changed again to 777, due to Nextcloud switching from root to www-data, breaking group-based permissions.
|
||||
---
|
||||
|
||||
## Summary
|
||||
|
||||
These architecture decisions collectively create a robust, secure, and performant infrastructure:
|
||||
|
||||
- **Native Services** provide optimal performance and security
|
||||
- **Unix Sockets** eliminate network attack vectors
|
||||
- **Podman + systemd** delivers secure container orchestration
|
||||
- **Forward Authentication** enables centralized security without application changes
|
||||
- **Rootful Container Pattern** enables group-based socket access with infrastructure fact sharing
|
||||
|
||||
The combination results in an infrastructure that prioritizes security and performance while maintaining operational simplicity and reliability.
|
||||
|
||||
## References
|
||||
|
||||
- [Service Integration Guide](service-integration-guide.md)
|
||||
- [Authentik Deployment Guide](authentik-deployment-guide.md)
|
||||
- [Security Hardening](security-hardening.md)
|
||||
- [Authentik Role Documentation](../roles/authentik/README.md)
|
||||
Reference in New Issue
Block a user