Restricting Login

Introduction

LdapRecord-Laravel provides various ways you can prevent certain users from logging into your application. Let's walk through some approaches.

Using a Group Membership

To use a group membership for authorizing signing in to your application, we will use an authentication rule.

In our example application, we want to only allow users who are members of a single group to authenticate. This group will be called Help Desk.

Let's create our new authentication rule by running the below command:

php artisan ldap:make:rule OnlyHelpDeskUsers

A new rule will be created inside app/Ldap/Rules/OnlyHelpDeskUsers.php

Then, add the rule to your authentication provider:

// config/auth.php

'providers' => [
    // ...

    'users' => [
        'driver' => 'ldap',
        'model' => LdapRecord\Models\ActiveDirectory\User::class,
        'rules' => [
            App\Ldap\Rules\OnlyHelpDeskUsers::class, // <-- Added here.
        ],
    ],
],

Make sure you run php artisan config:clear if you are caching your configuration files.

In the newly generated rule, we can check for group membership in various ways, as well as check for nested group membership, and even for multiple group memberships.

Let's walk through each example.

Checking for a single group

When checking for a single group, we will use the relation exists() method:

use LdapRecord\Models\Model as LdapRecord;
use Illuminate\Database\Eloquent\Model as Eloquent;

/**
 * Check if the rule passes validation.
 *
 * @return bool
 */
public function passes(LdapRecord $user, Eloquent $model = null): bool
{
    return $user->groups()->exists(
        'cn=Help Desk,ou=Groups,dc=local,dc=com'
    );
}

With the exists() method, we can also use an LdapRecord Model instance:

This approach is useful, so an exception will be thrown when the group cannot be located.

public function passes(LdapRecord $user, Eloquent $model = null): bool
{
    return $user->groups()->exists(
        Group::findOrFail('cn=Help Desk,ou=Groups,dc=local,dc=com')
    );
}

Or; A Common Name (cn):

public function passes(LdapRecord $user, Eloquent $model = null): bool
{
    return $user->groups()->exists('Help Desk');
}

Checking for multiple groups

To check that the user has all of a given set of groups, we will use the exists() method:

public function passes(LdapRecord $user, Eloquent $model = null): bool
{
    return $user->groups()->exists(
        'cn=Help Desk,ou=Groups,dc=local,dc=com',
        'cn=Site Admins,ou=Groups,dc=local,dc=com'
    );
}

We can also use Model instances:

public function passes(LdapRecord $user, Eloquent $model = null): bool
{
    return $user->groups()->exists([
        Group::findOrFail('cn=Help Desk,ou=Groups,dc=local,dc=com'),
        Group::findOrFail('cn=Site Admins,ou=Groups,dc=local,dc=com'),
    ]);
}

Or; Common Names (cn):

public function passes(LdapRecord $user, Eloquent $model = null): bool
{
    return $user->groups()->exists([
        'Help Desk', 'Site Admins'
    ]);
}

Checking for any given groups

To check that a user has any of a given set of groups, we will use the contains() method:

public function passes(LdapRecord $user, Eloquent $model = null): bool
{
    return $user->groups()->contains([
        'Help Desk', 'Accounting'
    ]);
}

You can also provide a Model instance or Distinguished Name into the contains method.

This will allow members of either the Help Desk or Accounting group to authenticate.

Checking for nested group(s) recursively

Nested group checking allows LdapRecord to search recursively if a user is a member of a particular group.

For example, if a user is a member of an Accounting group, and this Accounting group is a member of an Office group, you can tell LdapRecord to search recursively for the Office group:

public function passes(LdapRecord $user, Eloquent $model = null): bool
{
    return $user->groups()->recursive()->exists('Office');
}

Using the above example without the recursive call, it will fail to determine the users group membership, since LdapRecord is only searching for immediate memberships of the user:

public function passes(LdapRecord $user, Eloquent $model = null): bool
{
    // Only searching immediate group memberships:
    return $user->groups()->exists('Office');
}

Using an Organizational Unit

To use an Organizational Unit which contains your users that you want to allow sign in to your application, we will leverage LdapRecord model scopes.

In our application, we have an Organizational Unit named Accounting with the following Distinguished Name:

ou=Accounting,ou=Users,dc=local,dc=com

Let's create a new model scope using the below command:

php artisan ldap:make:scope OnlyAccountingUsers

Now inside the generated scope, we will limit the query to only return users who are contained inside our Accounting OU:

<?php

namespace App\Ldap\Scopes;

use LdapRecord\Models\Model;
use LdapRecord\Models\Scope;
use LdapRecord\Query\Model\Builder;

class OnlyAccountingUsers implements Scope
{
    /**
     * Apply the scope to the given query.
     *
     * @param Builder $query
     * @param Model   $model
     *
     * @return void
     */
    public function apply(Builder $query, Model $model)
    {
        $query->in('ou=Accounting,ou=Users,dc=local,dc=com');

        // You can also make this "environment aware" if needed:
        // $query->in(env('LDAP_USER_SCOPE'));
    }
}

After modifying the scope, we can now add the scope to our LDAP user model.

If you are using one of the built-in predefined models, you can add the global scope to the model inside your AuthServiceProvider::boot() method:

// app/Providers/AuthServiceProvider.php

use App\Ldap\Scopes\OnlyAccountingUsers;

/**
 * Register any authentication / authorization services.
 *
 * @return void
 */
public function boot()
{
    $this->registerPolicies();

    \LdapRecord\Models\ActiveDirectory\User::addGlobalScope(
        new OnlyAccountingUsers
    );
}

If you have created your own LDAP model, add the scope in the inside your models static boot method:

<?php

namespace App\Ldap;

use LdapRecord\Models\Model;
use App\Ldap\Scopes\CompanyScope;

class User extends Model
{
    /**
     * The "booting" method of the model.
     *
     * @return void
     */
    protected static function boot()
    {
        parent::boot();

        static::addGlobalScope(new OnlyAccountingUsers);
    }
}

Now when you attempt to sign in to your application, only users who are contained inside the Accounting OU will be allowed to authenticate.

Using Only Manually Imported Users

To enforce only manually imported LDAP users who exist inside your database to sign in to your application, you must use an authentication rule.

LdapRecord-Laravel includes this authentication rule out-of-the-box:

LdapRecord\Laravel\Auth\Rules\OnlyImported

To use this rule, insert it into the rules array into your authentication provider configuration inside the config/auth.php file:

// config/auth.php

'providers' => [
    // ...

    'users' => [
        'driver' => 'ldap',
        'model' => LdapRecord\Models\ActiveDirectory\User::class,
        'rules' => [
            LdapRecord\Laravel\Auth\Rules\OnlyImported::class, // <-- Added here.
        ],
    ],
],