Configuring custom authentication for FTP server

[djechelon]

Hello,
I would like to configure a custom authentication system for virtual FTP accounts.
I have recently used vsftp, configuring it through YaST, however it requires me to set up a UNIX account for each user that wants to log in.

Instead, I need to create a virtual domain hosting environment, where each user with a UNIX account can set up FTP accounts for each domain of their customers. I don't want a UNIX account for each domain name.

Each virtual FTP user has its home directory under its creator's home directory, for example
/home/djechelon/virtualhost/www.example1.com
/home/djechelon/virtualhost/www.example2.com
/home/djechelon/virtualhost/www.example3.com
/home/pippobaudo/virtualhost/www.example4.com
/home/pippobaudo/virtualhost/www.example5.com
/home/pippobaudo/virtualhost/www.example6.com
(I can still use symbolic links.....)

I was thinking about using a MySQL/SQLite database to store credentials, but how to map the triple (username, password, home) into vsftpd? In other words, how to make sure that I can login with username www.example5.org and have chroot access (as either user pippobaudo or Apache's wwwrun, not currently sure) to /home/pippobaudo/virtualhost/www.example5.com?

Is it possible? Do I need to use a different server?


Another question about it. I have several IP addresses: how to run two independent instances of vsftpd (or another FTP server software), each one with its own configuration, on different IP addresses?

Thank you in advance