Laravel CAS Client Package

A Laravel package for seamless single sign-on against One System (the CAS server). This package provides secure SSO authentication with JWT tokens, optional HMAC signature validation, and role-based access control.

Requirements

• PHP ^7.2 | ^7.3 | ^7.4 | ^8.0 (PHP 8.1+ recommended)
• Laravel ^7.0 | ^8.0 | ^9.0 | ^10.0 | ^11.0 | ^12.0
• firebase/php-jwt ^6.0, guzzlehttp/guzzle ^7.0 (installed automatically)

Features

• 🔐 Secure SSO Authentication - JWT token-based authentication
• 🛡️ Signature Validation - HMAC SHA-256 request signing
• 👥 Role-Based Access Control - Middleware for role protection
• 🔧 Easy Configuration - Environment-based setup
• 📝 Comprehensive Logging - Authentication event tracking
• ⚡ Performance Optimized - Token caching and validation
• 🎯 Laravel Integration - Native Laravel guards and middleware

Installation

1. Install via Composer

composer require cas-system/laravel-client

2. Run the Installer (recommended)

php artisan cas:install

The installer publishes the config, adds the CasUserTrait to your User model and seeds the required .env keys. Then run the migration that adds the CAS columns to the users table:

php artisan migrate

Prefer to do it by hand? Publish just the config with the cas-client-config tag:

php artisan vendor:publish --tag=cas-client-config
php artisan migrate

3. Configure Environment Variables

Add the following to your .env file. The client_id / client_secret are issued when you register this client in One System — store the secret server-side only, never in browser code:

# One System (CAS) server
CAS_SERVER_URL=http://127.0.0.1:8001
CAS_CLIENT_ID=your_client_id
CAS_CLIENT_SECRET=your_client_secret

# Callback the browser is sent back to after login
CAS_CALLBACK_URL=https://yourapp.com/cas/callback

# Security settings (optional — must match the server if enabled)
CAS_ENABLE_SIGNATURE_VALIDATION=true
CAS_SIGNATURE_SECRET=your-shared-signature-secret

Quick Start

1. Protect Routes with Middleware

The service provider auto-registers two middleware aliases: cas.auth and cas.role.

// In routes/web.php

// Any authenticated CAS user
Route::middleware(['cas.auth'])->group(function () {
    Route::get('/dashboard', [DashboardController::class, 'index']);
    Route::get('/profile', [ProfileController::class, 'show']);
});

// Restrict by role — user needs ANY of the listed roles
Route::middleware(['cas.auth', 'cas.role:admin,manager'])->group(function () {
    Route::get('/admin', [AdminController::class, 'index']);
});

2. Manual Authentication

use CasSystem\LaravelClient\Facades\CasClient;

class AuthController extends Controller
{
    public function login(Request $request)
    {
        $returnUrl = $request->query('return_url', route('dashboard'));
        $loginUrl = CasClient::getLoginUrl($returnUrl);
        return redirect($loginUrl);
    }

    public function callback(Request $request)
    {
        $token = $request->query('token');
        
        if (!$token) {
            return redirect()->route('login')->with('error', 'No authentication token provided');
        }

        $user = CasClient::validateToken($token);
        
        if ($user) {
            // Store user data in session
            session([
                'cas_user' => $user,
                'cas_token' => $token,
                'authenticated' => true
            ]);
            
            return redirect()->route('dashboard')->with('success', 'Login successful');
        }
        
        return redirect()->route('login')->with('error', 'Authentication failed');
    }

    public function logout(Request $request)
    {
        $token = session('cas_token');
        
        // Logout from CAS server
        CasClient::logout($token);
        
        // Clear local session
        session()->forget(['cas_user', 'cas_token', 'authenticated']);
        session()->invalidate();
        session()->regenerateToken();
        
        return redirect('/')->with('success', 'Logged out successfully');
    }
}

3. Access User Data

// In your controllers
public function dashboard(Request $request)
{
    $user = session('cas_user');
    $username = $user['username'];
    $email = $user['email'];
    $roles = $user['roles'] ?? [];
    
    return view('dashboard', compact('user', 'username', 'email', 'roles'));
}

// Check user roles
use CasSystem\LaravelClient\Facades\CasClient;

if (CasClient::userHasRole($user, 'admin')) {
    // User has admin role
}

if (CasClient::userHasAnyRole($user, ['admin', 'manager'])) {
    // User has admin OR manager role
}

if (CasClient::userHasAllRoles($user, ['user', 'verified'])) {
    // User has BOTH user AND verified roles
}

4. Blade Templates

{{-- In your Blade templates --}}
@if(session('authenticated'))
    <div class="user-info">
        <h3>Welcome, {{ session('cas_user.name') }}</h3>
        <p>Email: {{ session('cas_user.email') }}</p>
        <p>Roles: {{ implode(', ', session('cas_user.roles', [])) }}</p>
    </div>
    
    <form method="POST" action="{{ route('cas.logout') }}">
        @csrf
        <button type="submit" class="btn btn-danger">Logout</button>
    </form>
@else
    <a href="{{ route('cas.login') }}" class="btn btn-primary">Sign in with One System</a>
@endif

Configuration

Environment Variables

# Required Settings
CAS_SERVER_URL=http://127.0.0.1:8001              # One System (CAS) server URL
CAS_CLIENT_ID=your_client_id                      # Your registered client ID
CAS_CLIENT_SECRET=your_client_secret              # Client secret (server-side only)

# Callback Configuration
CAS_CALLBACK_URL=https://yourapp.com/cas/callback # Where the server redirects after login

# Security Settings
CAS_ENABLE_SIGNATURE_VALIDATION=true              # Enable HMAC request signing
CAS_SIGNATURE_SECRET=your-shared-signature-secret # HMAC signature secret (must match server)
CAS_VERIFY_SSL=true                               # Verify SSL certificates

# Optional Settings
CAS_TIMEOUT=30                                     # HTTP request timeout (seconds)
CAS_USER_MODEL=App\Models\User                     # Eloquent User model (uses CasUserTrait)
CAS_USER_DASHBOARD=/dashboard                      # Redirect target after login
CAS_ROUTES_ENABLED=true                            # Register the package's /cas/* routes
CAS_CACHE_ENABLED=true                            # Enable user data caching
CAS_CACHE_TTL=3600                                # Cache time-to-live (seconds)
CAS_LOGGING_ENABLED=true                          # Enable authentication logging

Advanced Configuration

Edit config/cas-client.php for advanced options:

return [
    // User management — a local User record is found/created on successful login
    'user' => [
        'create_local_users' => true,
        'model' => env('CAS_USER_MODEL', 'App\Models\Auth\User'),
        'defaults' => [
            'user_type' => 'Guest',
        ],
    ],

    // Route configuration — package routes auto-registered under this prefix
    'routes' => [
        'enabled' => env('CAS_ROUTES_ENABLED', true),
        'prefix' => env('CAS_ROUTES_PREFIX', 'cas'),
        'middleware' => ['web'],
        'user_dashboard' => env('CAS_USER_DASHBOARD', '/dashboard'),
    ],

    // Cache validated user data to cut calls to the server
    'cache' => [
        'enabled' => env('CAS_CACHE_ENABLED', true),
        'ttl' => env('CAS_CACHE_TTL', 3600),
        'prefix' => 'cas_',
    ],

    // Logging configuration
    'logging' => [
        'enabled' => env('CAS_LOGGING_ENABLED', true),
        'channel' => env('CAS_LOG_CHANNEL', 'single'),
        'level' => env('CAS_LOG_LEVEL', 'info'),
    ],
];

Middleware

CasAuthentication Middleware

Protects routes requiring CAS authentication:

Route::middleware(['cas.auth'])->group(function () {
    Route::get('/protected', [Controller::class, 'method']);
});

CasRole Middleware

Protects routes requiring specific roles:

// Single role
Route::middleware(['cas.auth', 'cas.role:admin'])->group(function () {
    Route::get('/admin', [AdminController::class, 'index']);
});

// Multiple roles (user needs ANY of these roles)
Route::middleware(['cas.auth', 'cas.role:admin,manager,supervisor'])->group(function () {
    Route::get('/management', [ManagementController::class, 'index']);
});

API Reference

CasAuthService Methods

// Build the SSO login URL -> {CAS_SERVER_URL}/sso/login?client_id=...
$loginUrl = CasClient::getLoginUrl($returnUrl);

// Validate a single-use token SERVER-TO-SERVER.
// POST {CAS_SERVER_URL}/api/sso/validate  { token, client_id, client_secret }
// On 200 returns the user array { id, username, email, ... }, else null.
$user = CasClient::validateToken($token);

// Get cached user data (no network call)
$user = CasClient::getUserFromToken($token);

// Service-to-service token issuance for a known user.
// POST {CAS_SERVER_URL}/api/sso/token  { client_id, client_secret, username }
$result = CasClient::generateSSOToken('jane.doe'); // ['token' => ..., 'redirect_url' => ...]

// Logout -> POST {CAS_SERVER_URL}/api/logout
$success = CasClient::logout($token);

// Role checking helpers
$hasRole = CasClient::userHasRole($user, 'admin');
$hasAnyRole = CasClient::userHasAnyRole($user, ['admin', 'manager']);
$hasAllRoles = CasClient::userHasAllRoles($user, ['user', 'verified']);

User Data Structure

$user = [
    'id' => 1,
    'username' => 'john_doe',
    'email' => 'john@example.com',
    'name' => 'John Doe',
    'roles' => ['user', 'manager'],
    // Additional fields from CAS server
];

Security Features

Signature Validation

When enabled, all requests to the CAS server are signed with HMAC SHA-256:

// Automatic signature generation
$signature = hash_hmac('sha256', $payload, $secret);

The payload includes:

• HTTP method
• Request URI
• Request body
• Timestamp
• Client ID

Token Caching

User data is cached to reduce CAS server load:

// Cached for performance
Cache::put("cas_user_{$token}", $userData, $ttl);

Error Handling

Comprehensive error handling for all CAS operations:

try {
    $user = CasClient::validateToken($token);
} catch (CasAuthException $e) {
    Log::error('CAS authentication failed', ['error' => $e->getMessage()]);
}

Troubleshooting

Common Issues

1. Authentication Loop

   • Check CAS_CALLBACK_URL matches your route
   • Verify session configuration
   • Ensure middleware order is correct

2. Token Validation Fails

   • Verify client credentials in CAS server
   • Check CAS_SIGNATURE_SECRET if using signatures
   • Ensure CAS server is accessible

3. Role Access Denied

   • Verify user has required roles in CAS
   • Check role middleware configuration
   • Ensure roles are properly synced

Debug Mode

Enable debug logging:

CAS_LOGGING_ENABLED=true
CAS_LOG_LEVEL=debug

Testing

Test your configuration:

# Test One System (CAS) server connectivity
curl -I http://127.0.0.1:8001/health

# Test token validation
php artisan tinker
>>> app(\CasSystem\LaravelClient\Services\CasAuthService::class)->validateToken('your-test-token');

License

This package is open-sourced software licensed under the MIT license.

Support

For support, please contact your CAS system administrator or create an issue in the project repository.

Contributing

Please see CONTRIBUTING.md for details on how to contribute to this package.

Changelog

Please see CHANGELOG.md for details on recent changes.