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homelab/homelab-rbac.md
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rock d146f7e3af iam: add memory scope + service accounts to Authentik
- Add 'memory' scope property mapping with claims:
  - memory_projects: project-level access filter
  - memory_visibility: public/private visibility
  - memory_role: admin/user/portfolio-agent
- Add capability groups: llm-users, memory-users, memory-writers
- Add service account provisioning for portfolio-agent, memory-agent
- Service accounts use client_credentials flow
- Add homelab-rbac.md design doc (Authentik-centric model)
2026-09-03 16:27:39 -07:00

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# Homelab RBAC Design
**Authentik as Universal Identity Provider** — Single source of truth for all identity, groups, and permissions. Services validate JWTs and trust claims; no separate auth systems.
## Design Principles
1. **Authentik = Policy Decision Point** — All access decisions computed in Authentik, embedded in JWT claims
2. **Services = Policy Enforcement Points** — Validate JWT signature via JWKS, trust claims blindly
3. **Zero Service-Side RBAC** — No local user/role tables, no permission logic in services
4. **Claims Are The API** — Each service defines what claims it needs; Authentik provides them
---
## Architecture
```
┌─────────────────────────────────────────────────────────────────────────────┐
│ Clients │
│ ┌──────────┐ ┌──────────┐ ┌──────────┐ ┌──────────┐ ┌──────────┐ │
│ │ Browser │ │ CLI │ │ Mobile │ │ Agent │ │ CI/CD │ │
│ └────┬─────┘ └────┬─────┘ └────┬─────┘ └────┬─────┘ └────┬─────┘ │
└────────┼─────────────┼─────────────┼─────────────┼─────────────┼────────────┘
│ │ │ │ │
│ auth_code │ device │ device │ client │ client
│ + PKCE │ code │ code │ credentials│ credentials
│ │ │ │ │
└─────────────┴─────────────┴─────────────┴─────────────┴─────────────┐
┌─────────────────────────────────────────────────────────────────────────────────┐
│ AUTHENTIK (Policy Decision Point) │
│ │
│ ┌─────────────────┐ ┌─────────────────┐ ┌───────────────────────────────┐ │
│ │ Users │ │ Groups │ │ User Attributes │ │
│ │ │ │ │ │ │ │
│ │ rock (human) │ │ homelab-admins │ │ memory_projects: ["*"] │ │
│ │ portfolio-sa │ │ llm-admins │ │ memory_visibility: private │ │
│ │ (svc account) │ │ memory-admins │ │ minio_policy: consoleAdmin │ │
│ └─────────────────┘ └─────────────────┘ └───────────────────────────────┘ │
│ │ │
│ ▼ │
│ ┌──────────────────────────────────────────────────────────────────────────┐ │
│ │ Property Mappings (Scope → Claim) │ │
│ │ │ │
│ │ scope: groups → claim: groups (group names list) │ │
│ │ scope: permissions → claim: permissions (computed from groups) │ │
│ │ scope: memory → claims: memory_projects, memory_visibility, │ │
│ │ memory_role (from user attrs + groups) │ │
│ │ scope: minio → claim: policy (MinIO policy name) │ │
│ └──────────────────────────────────────────────────────────────────────────┘ │
│ │ │
│ ▼ │
│ ┌──────────────────────────────────────────────────────────────────────────┐ │
│ │ JWT Token (signed) │ │
│ │ { │ │
│ │ "sub": "abc123", │ │
│ │ "groups": ["homelab-admins", "memory-admins"], │ │
│ │ "permissions": ["*"], │ │
│ │ "memory_projects": ["*"], │ │
│ │ "memory_visibility": "private", │ │
│ │ "memory_role": "admin", │ │
│ │ "policy": "consoleAdmin" │ │
│ │ } │ │
│ └──────────────────────────────────────────────────────────────────────────┘ │
└────────────────────────────────────────┬────────────────────────────────────────┘
JWT (Authorization: Bearer)
┌──────────────────────────────┼──────────────────────────────┐
│ │ │
▼ ▼ ▼
┌───────────────────┐ ┌───────────────────┐ ┌───────────────────┐
│ API Gateway │ │ Memory Service │ │ MinIO │
│ │ │ (Poimen) │ │ │
│ 1. Validate JWT │ │ 1. Validate JWT │ │ 1. Validate JWT │
│ 2. Read claims: │ │ 2. Read claims: │ │ 2. Read claims: │
│ - permissions │ │ - memory_* │ │ - policy │
│ 3. Allow/deny │ │ 3. Filter rows │ │ 3. Map to IAM │
│ │ │ │ │ │
│ NO local RBAC │ │ NO local RBAC │ │ NO local RBAC │
└───────────────────┘ └───────────────────┘ └───────────────────┘
```
---
## Authentik Configuration
### Groups (in Authentik)
| Group | Purpose | `is_superuser` |
|-------|---------|----------------|
| `homelab-admins` | Universal admin, full access to everything | `true` |
| `llm-admins` | LLM service management | `false` |
| `memory-admins` | Memory service management | `false` |
| `minio-admins` | MinIO storage management | `false` |
| `llm-users` | Can call LLM inference (no admin) | `false` |
| `memory-users` | Can query memory (no write) | `false` |
### User Attributes (stored on user object)
Fine-grained scopes stored as user attributes in Authentik:
| Attribute | Type | Example | Purpose |
|-----------|------|---------|---------|
| `memory_projects` | `string[]` | `["homelab", "portfolio"]` or `["*"]` | Which projects user can access |
| `memory_visibility` | `string` | `"public"` or `"private"` | Max visibility level |
| `minio_policy` | `string` | `"portfolio-rw"` | Override MinIO policy (optional) |
### Property Mappings (Scopes → Claims)
#### 1. `permissions` scope (existing)
```python
# Already in authentik-provision.py
GROUP_PERMISSIONS = {
"homelab-admins": ["*"],
"llm-admins": ["llm:read", "llm:write", "llm:inference"],
"llm-users": ["llm:inference"],
"memory-admins": ["memory:read", "memory:write", "memory:admin"],
"memory-users": ["memory:read"],
"minio-admins": ["minio:read", "minio:write"],
# ...
}
perms = set()
for group in request.user.groups.all():
perms.update(GROUP_PERMISSIONS.get(group.name, []))
return {"permissions": sorted(perms)}
```
#### 2. `memory` scope (NEW - to add)
```python
# Memory service claims - reads from user attributes + group membership
_MEMORY_EXPR = """
# Default scopes
projects = request.user.attributes.get("memory_projects", [])
visibility = request.user.attributes.get("memory_visibility", "public")
role = "user"
# Admin overrides
if request.user.ak_groups.filter(name="homelab-admins").exists():
projects = ["*"]
visibility = "private"
role = "admin"
elif request.user.ak_groups.filter(name="memory-admins").exists():
visibility = "private"
role = "admin"
# Service account specific configs
SA_CONFIGS = {
"portfolio-agent": {
"projects": ["homelab", "portfolio"],
"visibility": "public",
"role": "portfolio-agent"
},
"memory-agent": {
"projects": ["*"],
"visibility": "private",
"role": "authenticated-user"
}
}
if request.user.username in SA_CONFIGS:
cfg = SA_CONFIGS[request.user.username]
projects = cfg["projects"]
visibility = cfg["visibility"]
role = cfg["role"]
return {
"memory_projects": projects,
"memory_visibility": visibility,
"memory_role": role
}
"""
```
#### 3. `minio` scope (existing)
```python
# Already in authentik-provision.py
_POLICY_EXPR = """
# Check for explicit policy override in user attributes
explicit = request.user.attributes.get("minio_policy")
if explicit:
return {"policy": explicit}
# Group-based defaults
if request.user.ak_groups.filter(name="homelab-admins").exists():
return {"policy": "consoleAdmin"}
elif request.user.ak_groups.filter(name="minio-admins").exists():
return {"policy": "readwrite"}
else:
return {"policy": "readonly"}
"""
```
---
## Service Claim Contracts
Each service documents what JWT claims it expects. Authentik must provide them.
### API Gateway (`api.riotpiao.com`)
**Required Claims:**
```json
{
"permissions": ["llm:inference", "..."] // Check against required permission
}
```
**Enforcement:**
```go
// Gateway just checks if required permission is in claims
if !slices.Contains(claims.Permissions, "llm:inference") {
return 403
}
```
### Memory Service (`memory.riotpiao.com`)
**Required Claims:**
```json
{
"sub": "user-id", // Owner for conversation filtering
"permissions": ["memory:read", "..."], // Capability check
"memory_projects": ["homelab", "..."], // Project filter (or ["*"])
"memory_visibility": "public|private", // Max visibility level
"memory_role": "admin|user|..." // Built-in role (optional)
}
```
**Enforcement:**
```rust
// Memory service filters results based on claims
fn filter_results(results: Vec<Doc>, claims: &Claims) -> Vec<Doc> {
results.into_iter().filter(|doc| {
// Project check
let project_ok = claims.memory_projects.contains("*")
|| claims.memory_projects.contains(&doc.project);
// Visibility check
let visibility_ok = match claims.memory_visibility.as_str() {
"private" => true, // Can see everything
"public" => doc.visibility == "public",
_ => false,
};
// Owner check for conversations
let owner_ok = doc.resource_type != "conversation"
|| doc.owner == claims.sub;
project_ok && visibility_ok && owner_ok
}).collect()
}
```
### MinIO (`minio.riotpiao.com`)
**Required Claims:**
```json
{
"policy": "consoleAdmin|readwrite|readonly|<custom>"
}
```
**Enforcement:**
- MinIO natively reads `policy` claim via `MINIO_IDENTITY_OPENID_CLAIM_NAME=policy`
- Looks up policy by name in MinIO's IAM policy store
- Built-in: `consoleAdmin`, `readwrite`, `readonly`, `writeonly`, `diagnostics`
- Custom policies created via `mc admin policy create`
---
## Service Accounts
Service accounts are Authentik users with `type: service_account` and client credentials grant.
### Creating a Service Account
```python
# In authentik-provision.py, add to SERVICES dict:
"portfolio-agent": {
"type": "service_account", # No redirect URIs
"grant_types": ["client_credentials"],
"client_secret_source": ("portfolio", "portfolio-oidc", "CLIENT_SECRET"),
"generate_if_missing": True,
"display_name": "Portfolio Agent",
"groups": ["llm-users", "memory-users"], # Group membership
"attributes": { # User attributes
"memory_projects": ["homelab", "portfolio"],
"memory_visibility": "public"
}
}
```
### Service Account Token Flow
```bash
# 1. Service requests token with client credentials
curl -X POST https://authentik.riotpiao.com/application/o/token/ \
-d "grant_type=client_credentials" \
-d "client_id=portfolio-agent" \
-d "client_secret=$SECRET" \
-d "scope=openid permissions memory"
# 2. Authentik returns JWT with claims
{
"access_token": "eyJ...",
"token_type": "Bearer",
"expires_in": 300
}
# 3. Service uses token to call API
curl https://api.riotpiao.com/v1/chat/completions \
-H "Authorization: Bearer eyJ..."
```
---
## User Onboarding
### Admin Creates User
```python
# 1. Create user via Authentik API
POST /api/v3/core/users/
{
"username": "alice",
"email": "[email protected]",
"groups": ["llm-users", "memory-users"],
"attributes": {
"memory_projects": ["homelab"],
"memory_visibility": "public"
}
}
# 2. Set password or send invite
POST /api/v3/core/users/{pk}/set_password/
or
POST /api/v3/stages/invitation/invitations/
```
### Grant Additional Access
```python
# Add to group (grants permissions via GROUP_PERMISSIONS mapping)
PATCH /api/v3/core/users/{pk}/
{
"groups": ["llm-users", "memory-users", "memory-admins"] # Added memory-admins
}
# Or update attributes for fine-grained scopes
PATCH /api/v3/core/users/{pk}/
{
"attributes": {
"memory_projects": ["homelab", "new-project"], # Added project
"memory_visibility": "private" # Upgraded visibility
}
}
```
### Offboard User
```python
# Deactivate (preserves audit trail)
PATCH /api/v3/core/users/{pk}/
{"is_active": false}
# Revoke all tokens immediately
POST /api/v3/core/users/{pk}/revoke_tokens/
```
---
## Implementation Checklist
### Phase 1: Add Memory Claims ⬜
1. Add `memory` scope property mapping to `authentik-provision.py`
2. Add scope to `poimen-memory` OAuth provider
3. Update Memory service to read claims instead of local RBAC
### Phase 2: Service Accounts ⬜
1. Add service account creation to `authentik-provision.py`
2. Create `portfolio-agent` service account
3. Test client credentials flow
### Phase 3: MinIO Fine-Grained ⬜
1. Create custom MinIO policies (`portfolio-rw`, `memory-rw`)
2. Update `minio` scope mapping for service accounts
3. Test bucket-level access
---
## Appendix: Claim Reference
| Claim | Source | Services |
|-------|--------|----------|
| `sub` | User ID (hashed) | All (owner checks) |
| `groups` | Group membership | ArgoCD, Grafana |
| `permissions` | Computed from groups | API Gateway, Memory |
| `memory_projects` | User attr + group | Memory |
| `memory_visibility` | User attr + group | Memory |
| `memory_role` | User attr + group | Memory |
| `policy` | User attr + group | MinIO |
| `immich_role` | Group membership | Immich |