I am using d365 online, I need to append custom logic in existing portal login.
Currently the login is authenticating user from contact entity and allows login. I want to add some validations like user account expire, is marked blocked etc. If any check fails stop user from login and show error message.
Also for authenticate thru google or linked in account I want to validate the email address already exists in contact entity in the system, if email id doesn't exists prevent user from login.
Please guide how to achieve above functionality