Laravel 4.2 Security

Configuration

Laravel aims to make implementing authentication very simple. In fact, almost everything is configured for you out of the box. The authentication configuration file is located at app/config/auth.php, which contains several well documented options for tweaking the behavior of the authentication facilities.

By default, Laravel includes a User model in your app/models directory which may be used with the default Eloquent authentication driver. Please remember when building the Schema for this Model to ensure that the password field is a minimum of 60 characters.

If your application is not using Eloquent, you may use the database authentication driver which uses the Laravel query builder.

Note: Before getting started, make sure that your users (or equivalent) table contains a nullable, string remember_token column of 100 characters. This column will be used to store a token for "remember me" sessions being maintained by your application. This can be done by using $table->rememberToken(); in a migration.

Storing Passwords

The Laravel Hash class provides secure Bcrypt hashing:

Hashing A Password Using Bcrypt

$password = Hash::make('secret');

Verifying A Password Against A Hash

if (Hash::check('secret', $hashedPassword))
{
	// The passwords match...
}

Checking If A Password Needs To Be Rehashed

if (Hash::needsRehash($hashed))
{
	$hashed = Hash::make('secret');
}

Authenticating Users

To log a user into your application, you may use the Auth::attempt method.

if (Auth::attempt(array('email' => $email, 'password' => $password)))
{
	return Redirect::intended('dashboard');
}

Take note that email is not a required option, it is merely used for example. You should use whatever column name corresponds to a "username" in your database. The Redirect::intended function will redirect the user to the URL they were trying to access before being caught by the authentication filter. A fallback URI may be given to this method in case the intended destination is not available.

When the attempt method is called, the auth.attempt event will be fired. If the authentication attempt is successful and the user is logged in, the auth.login event will be fired as well.

Determining If A User Is Authenticated

To determine if the user is already logged into your application, you may use the check method:

if (Auth::check())
{
	// The user is logged in...
}

Authenticating A User And "Remembering" Them

If you would like to provide "remember me" functionality in your application, you may pass true as the second argument to the attempt method, which will keep the user authenticated indefinitely (or until they manually logout). Of course, your users table must include the string remember_token column, which will be used to store the "remember me" token.

if (Auth::attempt(array('email' => $email, 'password' => $password), true))
{
	// The user is being remembered...
}

Note: If the attempt method returns true, the user is considered logged into the application.

Determining If User Authed Via Remember

If you are "remembering" user logins, you may use the viaRemember method to determine if the user was authenticated using the "remember me" cookie:

if (Auth::viaRemember())
{
	//
}

Authenticating A User With Conditions

You also may add extra conditions to the authenticating query:

if (Auth::attempt(array('email' => $email, 'password' => $password, 'active' => 1)))
{
    // The user is active, not suspended, and exists.
}

Note: For added protection against session fixation, the user's session ID will automatically be regenerated after authenticating.

Accessing The Logged In User

Once a user is authenticated, you may access the User model / record:

$email = Auth::user()->email;

To retrieve the authenticated user's ID, you may use the id method:

$id = Auth::id();

To simply log a user into the application by their ID, use the loginUsingId method:

Auth::loginUsingId(1);

Validating User Credentials Without Login

The validate method allows you to validate a user's credentials without actually logging them into the application:

if (Auth::validate($credentials))
{
	//
}

Logging A User In For A Single Request

You may also use the once method to log a user into the application for a single request. No sessions or cookies will be utilized.

if (Auth::once($credentials))
{
	//
}

Logging A User Out Of The Application

Auth::logout();

Manually Logging In Users

If you need to log an existing user instance into your application, you may simply call the login method with the instance:

$user = User::find(1);

Auth::login($user);

This is equivalent to logging in a user via credentials using the attempt method.

Protecting Routes

Route filters may be used to allow only authenticated users to access a given route. Laravel provides the auth filter by default, and it is defined in app/filters.php.

Protecting A Route

Route::get('profile', array('before' => 'auth', function()
{
	// Only authenticated users may enter...
}));

CSRF Protection

Laravel provides an easy method of protecting your application from cross-site request forgeries.

Inserting CSRF Token Into Form

<input type="hidden" name="_token" value="<?php echo csrf_token(); ?>">

Validate The Submitted CSRF Token

Route::post('register', array('before' => 'csrf', function()
{
    return 'You gave a valid CSRF token!';
}));

HTTP Basic Authentication

HTTP Basic Authentication provides a quick way to authenticate users of your application without setting up a dedicated "login" page. To get started, attach the auth.basic filter to your route:

Protecting A Route With HTTP Basic

Route::get('profile', array('before' => 'auth.basic', function()
{
	// Only authenticated users may enter...
}));

By default, the basic filter will use the email column on the user record when authenticating. If you wish to use another column you may pass the column name as the first parameter to the basic method in your app/filters.php file:

Route::filter('auth.basic', function()
{
	return Auth::basic('username');
});

Setting Up A Stateless HTTP Basic Filter

You may also use HTTP Basic Authentication without setting a user identifier cookie in the session, which is particularly useful for API authentication. To do so, define a filter that returns the onceBasic method:

Route::filter('basic.once', function()
{
	return Auth::onceBasic();
});

If you are using PHP FastCGI, HTTP Basic authentication will not work correctly by default. The following lines should be added to your .htaccess file:

RewriteCond %{HTTP:Authorization} ^(. )$
RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]

Password Reminders & Reset

Model & Table

Most web applications provide a way for users to reset their forgotten passwords. Rather than forcing you to re-implement this on each application, Laravel provides convenient methods for sending password reminders and performing password resets. To get started, verify that your User model implements the Illuminate\Auth\Reminders\RemindableInterface contract. Of course, the User model included with the framework already implements this interface, and uses the Illuminate\Auth\Reminders\RemindableTrait to include the methods needed to implement the interface.

Implementing The RemindableInterface

use Illuminate\Auth\Reminders\RemindableTrait;
use Illuminate\Auth\Reminders\RemindableInterface;

class User extends Eloquent implements RemindableInterface {

	use RemindableTrait;

}

Generating The Reminder Table Migration

Next, a table must be created to store the password reset tokens. To generate a migration for this table, simply execute the auth:reminders-table Artisan command:

php artisan auth:reminders-table

php artisan migrate

Password Reminder Controller

Now we're ready to generate the password reminder controller. To automatically generate a controller, you may use the auth:reminders-controller Artisan command, which will create a RemindersController.php file in your app/controllers directory.

php artisan auth:reminders-controller

The generated controller will already have a getRemind method that handles showing your password reminder form. All you need to do is create a password.remind view. This view should have a basic form with an email field. The form should POST to the RemindersController@postRemind action.

A simple form on the password.remind view might look like this:

<form action="{{ action('RemindersController@postRemind') }}" method="POST">
	<input type="email" name="email">
	<input type="submit" value="Send Reminder">
</form>

In addition to getRemind, the generated controller will already have a postRemind method that handles sending the password reminder e-mails to your users. This method expects the email field to be present in the POST variables. If the reminder e-mail is successfully sent to the user, a status message will be flashed to the session. If the reminder fails, an error message will be flashed instead.

Within the postRemind controller method you may modify the message instance before it is sent to the user:

Password::remind(Input::only('email'), function($message)
{
	$message->subject('Password Reminder');
});

Your user will receive an e-mail with a link that points to the getReset method of the controller. The password reminder token, which is used to identify a given password reminder attempt, will also be passed to the controller method. The action is already configured to return a password.reset view which you should build. The token will be passed to the view, and you should place this token in a hidden form field named token. In addition to the token, your password reset form should contain email, password, and password_confirmation fields. The form should POST to the RemindersController@postReset method.

A simple form on the password.reset view might look like this:

<form action="{{ action('RemindersController@postReset') }}" method="POST">
	<input type="hidden" name="token" value="{{ $token }}">
	<input type="email" name="email">
	<input type="password" name="password">
	<input type="password" name="password_confirmation">
	<input type="submit" value="Reset Password">
</form>

Finally, the postReset method is responsible for actually changing the password in storage. In this controller action, the Closure passed to the Password::reset method sets the password attribute on the User and calls the save method. Of course, this Closure is assuming your User model is an Eloquent model; however, you are free to change this Closure as needed to be compatible with your application's database storage system.

If the password is successfully reset, the user will be redirected to the root of your application. Again, you are free to change this redirect URL. If the password reset fails, the user will be redirect back to the reset form, and an error message will be flashed to the session.

Password Validation

By default, the Password::reset method will verify that the passwords match and are >= six characters. You may customize these rules using the Password::validator method, which accepts a Closure. Within this Closure, you may do any password validation you wish. Note that you are not required to verify that the passwords match, as this will be done automatically by the framework.

Password::validator(function($credentials)
{
	return strlen($credentials['password']) >= 6;
});

Note: By default, password reset tokens expire after one hour. You may change this via the reminder.expire option of your app/config/auth.php file.

Encryption

Laravel provides facilities for strong AES encryption via the mcrypt PHP extension:

Encrypting A Value

$encrypted = Crypt::encrypt('secret');

Note: Be sure to set a 16, 24, or 32 character random string in the key option of the app/config/app.php file. Otherwise, encrypted values will not be secure.

Decrypting A Value

$decrypted = Crypt::decrypt($encryptedValue);

Setting The Cipher & Mode

You may also set the cipher and mode used by the encrypter:

Crypt::setMode('ctr');

Crypt::setCipher($cipher);

Authentication Drivers

Laravel offers the database and eloquent authentication drivers out of the box. For more information about adding additional authentication drivers, check out the Authentication extension documentation.