# Web Gateway Tenant RBAC Contract

**Contract ID:** CONTRACT-GATEWAY-RBAC-001
**Status:** APPROVED
**Effective Date:** 2025-12-07
**Owners:** Gateway Guild, Authority Guild, Web UI Guild

## Overview

This contract defines the tenant isolation and role-based access control (RBAC) model for the StellaOps Web Gateway, ensuring consistent authorization across all API endpoints and UI components.

## Tenant Model

### Tenant Hierarchy

```
Organization (Org)
├── Tenant A
│   ├── Project 1
│   │   └── Resources...
│   └── Project 2
│       └── Resources...
└── Tenant B
    └── Project 3
        └── Resources...
```

### Tenant Identification

Tenants are identified through:

1. **JWT Claims:** `tenant_id` or `stellaops:tenant` claim
2. **Header:** `X-Tenant-Id` header (for service-to-service)
3. **Path Parameter:** `/tenants/{tenantId}/...` routes

### Tenant Resolution Priority

```
1. Path parameter (explicit)
2. JWT claim (authenticated user context)
3. X-Tenant-Id header (service-to-service)
4. Default tenant (configuration fallback)
```

## Role Definitions

### Built-in Roles

| Role | Description | Scope |
|------|-------------|-------|
| `org:admin` | Organization administrator | Org-wide |
| `org:reader` | Organization read-only access | Org-wide |
| `tenant:admin` | Tenant administrator | Single tenant |
| `tenant:operator` | Can modify resources within tenant | Single tenant |
| `tenant:viewer` | Read-only access to tenant | Single tenant |
| `project:admin` | Project administrator | Single project |
| `project:contributor` | Can modify project resources | Single project |
| `project:viewer` | Read-only project access | Single project |
| `policy:admin` | Policy management | Tenant-wide |
| `scanner:operator` | Scanner operations | Tenant-wide |
| `airgap:admin` | Air-gap operations | Tenant-wide |

### Role Hierarchy

```
org:admin
├── org:reader
├── tenant:admin
│   ├── tenant:operator
│   │   └── tenant:viewer
│   ├── policy:admin
│   ├── scanner:operator
│   └── airgap:admin
└── project:admin
    ├── project:contributor
    └── project:viewer
```

## Scopes

### OAuth 2.0 Scopes

| Scope | Description | Required Role |
|-------|-------------|---------------|
| `policy:read` | Read policies and profiles | `tenant:viewer` |
| `policy:edit` | Create/modify policies | `policy:admin` |
| `policy:activate` | Activate policies | `policy:admin` |
| `scanner:read` | View scan results | `tenant:viewer` |
| `scanner:execute` | Execute scans | `scanner:operator` |
| `airgap:seal` | Seal/unseal environment | `airgap:admin` |
| `airgap:status:read` | Read sealed mode status | `tenant:viewer` |
| `airgap:verify` | Verify bundles | `tenant:operator` |
| `export:read` | Read exports | `tenant:viewer` |
| `export:create` | Create exports | `tenant:operator` |
| `admin:users` | Manage users | `tenant:admin` |
| `admin:settings` | Manage settings | `tenant:admin` |

### Scope Inheritance

Child scopes are automatically granted when parent scope is present:

```yaml
scope_inheritance:
  "policy:edit": ["policy:read"]
  "policy:activate": ["policy:read", "policy:edit"]
  "scanner:execute": ["scanner:read"]
  "export:create": ["export:read"]
  "admin:users": ["admin:settings"]
```

## Resource Authorization

### Resource Types

| Resource Type | Tenant Scoped | Project Scoped | Description |
|--------------|---------------|----------------|-------------|
| `risk_profile` | Yes | No | Risk scoring profiles |
| `policy_pack` | Yes | No | Policy bundles |
| `scan_result` | Yes | Yes | Scan outputs |
| `export` | Yes | Yes | Export jobs |
| `finding` | Yes | Yes | Vulnerability findings |
| `vex_document` | Yes | Yes | VEX statements |
| `sealed_mode` | Yes | No | Air-gap state |
| `user` | Yes | No | Tenant users |
| `project` | Yes | No | Projects |

### Authorization Rules

```yaml
# authorization-rules.yaml
rules:
  - resource: risk_profile
    actions:
      read:
        required_scopes: [policy:read]
        tenant_isolation: strict
      create:
        required_scopes: [policy:edit]
        tenant_isolation: strict
      update:
        required_scopes: [policy:edit]
        tenant_isolation: strict
      activate:
        required_scopes: [policy:activate]
        tenant_isolation: strict
      delete:
        required_scopes: [policy:edit]
        tenant_isolation: strict
        require_role: policy:admin

  - resource: scan_result
    actions:
      read:
        required_scopes: [scanner:read]
        tenant_isolation: strict
        project_isolation: optional
      create:
        required_scopes: [scanner:execute]
        tenant_isolation: strict
      delete:
        required_scopes: [scanner:execute]
        tenant_isolation: strict
        require_role: scanner:operator

  - resource: sealed_mode
    actions:
      read:
        required_scopes: [airgap:status:read]
        tenant_isolation: strict
      seal:
        required_scopes: [airgap:seal]
        tenant_isolation: strict
        require_role: airgap:admin
        audit: required
      unseal:
        required_scopes: [airgap:seal]
        tenant_isolation: strict
        require_role: airgap:admin
        audit: required
```

## Tenant Isolation

### Strict Isolation

All data access is tenant-scoped by default:

```sql
-- Example: All queries include tenant filter
SELECT * FROM findings
WHERE tenant_id = @current_tenant_id
  AND deleted_at IS NULL;
```

### Cross-Tenant Access

Cross-tenant access is prohibited except:

1. **Organization admins** can access all tenants in their org
2. **Internal services** with explicit `cross_tenant` scope
3. **Aggregation endpoints** with `org:reader` role

### Isolation Enforcement Points

| Layer | Enforcement |
|-------|-------------|
| Gateway | Validates tenant claim, injects X-Tenant-Id |
| Service | Applies tenant filter to all queries |
| Database | Row-level security (RLS) policies |
| Cache | Tenant-prefixed cache keys |

## JWT Claims

### Required Claims

```json
{
  "sub": "user-uuid",
  "aud": ["stellaops-api"],
  "iss": "https://auth.stellaops.io",
  "exp": 1701936000,
  "iat": 1701932400,
  "stellaops:tenant": "tenant-uuid",
  "stellaops:org": "org-uuid",
  "stellaops:roles": ["tenant:operator", "policy:admin"],
  "scope": "policy:read policy:edit scanner:read"
}
```

### Custom Claims

| Claim | Type | Description |
|-------|------|-------------|
| `stellaops:tenant` | string | Current tenant UUID |
| `stellaops:org` | string | Organization UUID |
| `stellaops:roles` | string[] | Assigned roles |
| `stellaops:projects` | string[] | Accessible projects |
| `stellaops:tier` | string | Rate limit tier |

## Gateway Implementation

### Authorization Middleware

```csharp
// AuthorizationMiddleware.cs
public class TenantAuthorizationMiddleware
{
    public async Task InvokeAsync(HttpContext context, RequestDelegate next)
    {
        // 1. Extract tenant from JWT/header/path
        var tenantId = ResolveTenantId(context);

        // 2. Validate tenant access
        if (!await ValidateTenantAccess(context.User, tenantId))
        {
            context.Response.StatusCode = 403;
            return;
        }

        // 3. Set tenant context for downstream
        context.Items["TenantId"] = tenantId;
        context.Request.Headers["X-Tenant-Id"] = tenantId;

        await next(context);
    }
}
```

### Scope Authorization

```csharp
// ScopeAuthorization.cs
public static class ScopeAuthorization
{
    public static IResult? RequireScope(HttpContext context, string requiredScope)
    {
        var scopes = context.User.FindFirst("scope")?.Value?.Split(' ') ?? [];

        if (!scopes.Contains(requiredScope) && !HasInheritedScope(scopes, requiredScope))
        {
            return Results.Problem(
                title: "Forbidden",
                detail: $"Missing required scope: {requiredScope}",
                statusCode: 403);
        }

        return null; // Access granted
    }
}
```

## Web UI Integration

### Route Guards

```typescript
// route-guards.ts
export const TenantGuard: CanActivateFn = (route, state) => {
  const auth = inject(AuthService);
  const requiredRoles = route.data['roles'] as string[];

  if (!auth.hasAnyRole(requiredRoles)) {
    return inject(Router).createUrlTree(['/unauthorized']);
  }

  return true;
};

// Usage in routes
{
  path: 'policy/studio',
  component: PolicyStudioComponent,
  canActivate: [TenantGuard],
  data: { roles: ['policy:admin', 'tenant:admin'] }
}
```

### Scope-Based UI Elements

```typescript
// rbac.directive.ts
@Directive({ selector: '[requireScope]' })
export class RequireScopeDirective {
  @Input() set requireScope(scope: string) {
    this.updateVisibility(scope);
  }

  private updateVisibility(scope: string): void {
    const hasScope = this.auth.hasScope(scope);
    this.viewContainer.clear();
    if (hasScope) {
      this.viewContainer.createEmbeddedView(this.templateRef);
    }
  }
}

// Usage in templates
<button *requireScope="'policy:activate'">Activate Policy</button>
```

## Audit Trail

### Audited Operations

All write operations are logged with:

```json
{
  "timestamp": "2025-12-07T10:30:00Z",
  "actor": {
    "userId": "user-uuid",
    "tenantId": "tenant-uuid",
    "roles": ["policy:admin"],
    "ipAddress": "192.168.1.100"
  },
  "action": "policy.activate",
  "resource": {
    "type": "policy_pack",
    "id": "pack-123",
    "version": 5
  },
  "outcome": "success",
  "details": {
    "previousStatus": "approved",
    "newStatus": "active"
  }
}
```

### Sensitive Operations

These operations require enhanced audit logging:

- `sealed_mode.seal` / `sealed_mode.unseal`
- `policy.activate`
- `export.create` (with PII)
- `user.role.assign`
- `tenant.settings.modify`

## Configuration

### Gateway RBAC Configuration

```yaml
# gateway/rbac.yaml
rbac:
  enabled: true
  strictTenantIsolation: true
  allowCrossTenantForOrgAdmin: true

  defaultRole: tenant:viewer
  defaultScopes:
    - policy:read
    - scanner:read

  roleBindings:
    tenant:admin:
      scopes:
        - policy:read
        - policy:edit
        - policy:activate
        - scanner:read
        - scanner:execute
        - airgap:status:read
        - export:read
        - export:create
        - admin:users
        - admin:settings

    policy:admin:
      scopes:
        - policy:read
        - policy:edit
        - policy:activate
```

## Error Responses

### 401 Unauthorized

```json
{
  "type": "https://stellaops.org/problems/unauthorized",
  "title": "Unauthorized",
  "status": 401,
  "detail": "Authentication required."
}
```

### 403 Forbidden

```json
{
  "type": "https://stellaops.org/problems/forbidden",
  "title": "Forbidden",
  "status": 403,
  "detail": "You do not have permission to access this resource.",
  "requiredScope": "policy:activate",
  "currentScopes": ["policy:read"]
}
```

### 404 Not Found (Tenant Isolation)

```json
{
  "type": "https://stellaops.org/problems/not-found",
  "title": "Not Found",
  "status": 404,
  "detail": "Resource not found."
}
```

Note: 404 is returned instead of 403 for resources in other tenants to prevent enumeration attacks.

## Changelog

| Date | Version | Change |
|------|---------|--------|
| 2025-12-07 | 1.0.0 | Initial contract definition |

## References

- [Auth Scopes Documentation](../security/auth-scopes.md)
- [RBAC Documentation](../security/scopes-and-roles.md)
- [Tenancy Overview](../security/tenancy-overview.md)
- [Rate Limit Design](./rate-limit-design.md)