User authorization in symfony 3

It is necessary to implement a simple user authorization. Now it works with such security.yml settings.

security: providers: in_memory: memory: users: admin: password: admin roles: 'ROLE_ADMIN' firewalls: dev: pattern: ^/(_(profiler|wdt)|css|images|js)/ security: false secured_area: pattern: ^/ anonymous: ~ form_login: login_path: /login check_path: /login_check logout: path: /logout target: / access_control: - { path: ^/login, roles: IS_AUTHENTICATED_ANONYMOUSLY } - { path: ^/, roles: ROLE_ADMIN } encoders: Symfony\Component\Security\Core\User\User: plaintext 

I need to make the login and password check happen according to my scheme. Those. all users are stored in another database in the users table. All work with this table is only to verify the username and password and get the email user. Verification of data from the login form is the first and last time this table will be used.

Registered routing

 login_check: path: /login_check defaults: { _controller: AppBundle:Security:check } 

but the check passes as if by this action. In checkAction, I'm trying to display simple text and stop the script, but the main page opens.