I have seen a couple of websites / tutorials to "access files and folders" controlled by Samba4.
I want to ask if it is possible to use Samba as the database, and allow a user to enter their username and password, then using PHP, connect to the Samba users list to check these credentials and authenticate.
I did this looong time ago with samba3 and PHP4. Sorry but I can't give you details right now but I used this: http://uranus.chrysocome.net/linux/php/php_smbauth.htm
Code will be like:
smbauth($username, $password, $primary_svr, $secondary_svr, $domain);
I didn't see support for PHP5 or if it is possible to install it via apt. Anyway, with the source and administrative privileges you can compile it.