Some events fired by wodSSHD will have Action parameter sent to your application, where they expect you to put it simple response to raised event - if action will be allowed or not.

Typical example would be LoginPassword event. Once user connects and provides username and password, you can check entered values and decide whether you will let user in or reject his connection. If you decide that password is correct, set Action variable to Allow. If you want to deny access to the system, set Action variable to Deny.