Simple PHP SSO integration for Laravel

Requirements

• Laravel 5.5+
• PHP 7.1+

Words meanings

• SSO - Single Sign-On.
• Server - page which works as SSO server, handles authentications, stores all sessions data.
• Broker - your page which is used visited by clients/users.
• Client/User - your every visitor.

How it works?

Client visits Broker and unique token is generated. When new token is generated we need to attach Client session to his session in Broker so he will be redirected to Server and back to Broker at this moment new session in Server will be created and associated with Client session in Broker's page. When Client visits other Broker same steps will be done except that when Client will be redirected to Server he already use his old session and same session id which associated with Broker#1.

Installation

Server

Install this package using composer.

$ composer require zefy/laravel-sso

Copy config file to Laravel project config/ folder.

$ php artisan vendor:publish --provider="andcarpi\LaravelSSOServer\SSOServiceProvider"

Create table where all brokers will be saved.

$ php artisan migrate --path=vendor/zefy/laravel-sso/database/migrations

Edit your app/Http/Kernel.php by removing throttle middleware and adding sessions middleware to api middlewares array. This is necessary because we need sessions to work in API routes and throttle middleware can block connections which we need.

'api' => [
    'bindings',
    \Illuminate\Session\Middleware\StartSession::class,
],

Now you should create brokers. You can create new broker using following Artisan CLI command:

$ php artisan sso:broker:create {name}

---

Broker

Install this package using composer.

$ composer require zefy/laravel-sso

Copy config file to Laravel project config/ folder.

$ php artisan vendor:publish --provider="andcarpi\LaravelSSOServer\SSOServiceProvider"

Change type value in config/laravel-sso.php file from server to broker.

Set 3 new options in your .env file:

SSO_SERVER_URL=
SSO_BROKER_NAME=
SSO_BROKER_SECRET=

SSO_SERVER_URL is your server's http url without trailing slash. SSO_BROKER_NAME and SSO_BROKER_SECRET must be data which exists in your server's brokers table.

Edit your app/Http/Kernel.php by adding \andcarpi\LaravelSSOServer\Middleware\SSOAutoLogin::class middleware to web middleware group. It should look like this:

protected $middlewareGroups = [
        'web' => [
            ...
            \andcarpi\LaravelSSOServer\Middleware\SSOAutoLogin::class,
        ],

        'api' => [
            ...
        ],
    ];

Last but not least, you need to edit app/Http/Controllers/Auth/LoginController.php. You should add two functions into LoginController class which will authenticate your client through SSO server but not your Broker page.

protected function attemptLogin(Request $request)
{
    $broker = new \andcarpi\LaravelSSOServer\LaravelSSOBroker;
    
    $credentials = $this->credentials($request);
    return $broker->login($credentials[$this->username()], $credentials['password']);
}

public function logout(Request $request)
{
    $broker = new \andcarpi\LaravelSSOServer\LaravelSSOBroker;
    
    $broker->logout();
    
    $this->guard()->logout();
    
    $request->session()->invalidate();
    
    return redirect('/');
}

That's all. For other Broker pages you should repeat everything from the beginning just changing your Broker name and secret in configuration file.

Example .env options:

SSO_SERVER_URL=https://server.test
SSO_BROKER_NAME=site1
SSO_BROKER_SECRET=892asjdajsdksja74jh38kljk2929023