man kftpusers (Formats) - /etc/ftpusers
NAME
/etc/ftpusers - FTP access list file
DESCRIPTION
/etc/ftpusers
contains a list of users that should be allowed or denied FTP access. Each line contains a user, optionally followed by (anything but is ignored). The semi-user matches any user. Users that has an explicit or that does not match any line, are allowed access. Anyone else is denied access.
Note that this is compatible with the old format, where this file contained a list of users that should be denied access.
EXAMPLES
This will deny anyone but and to use FTP: foo allow bar allow *
SEE ALSO
ftpd()