How can I force a specific password?

Question

How can I force a specific password for a specific user & not let that user change their password? I have a client that thinks that even if I force strong passwords via this plugin: https://wordpress.org/plugins/force-strong-passwords/ their users will use short & easy passwords. Thus, they want to set random 14 character passwords for every user & not let them change said passwords. Does anyone know how to do this?

Answer 1

You can use this code in your functions.php to restrict users below admin level from changing their passwords:

if ( is_admin() ) {
  add_action( 'init', 'disable_password_fields', 10 );
}

function disable_password_fields() {
  if ( ! current_user_can( 'activate_plugins' ) ) {
    $show_password_fields = add_filter( 'show_password_fields', '__return_false' );
  }
}

The admin should probably register each user manually if possible and select a strong password for them.

Edit - Changed user level check. Syntax.

Answer 2

This is a very vast question so excuse me for not adding code. I do have a map for you.

For sensible reasons, WordPress doesn't have a hook or filter that can help modify user passwords before they are saved in the database. The solution proposed by @jason-murray will hide the password fields in one location — on the user profile page.

However, users can update passwords using Forgot password feature. If you hide/disable it, you'd disable your users. Instead, you could just hook into the retrieve_password_message filter.

This sends an email to the user with an activation key and all. You can generate a password using wp_hash_password and wp_generate_password, sending it in the email and updating in the database. (Try finding out the rough statistics of the number of people and the frequency at which they forget and reset passwords.)

Also, there's no point setting up passwords manually for users, especially if you have a large number of users. When users register, you could hijack the pluggable wp_new_user_notification and generate a strong password, replace the default password generated by WordPress, and send a modified email to the user.