DOKK / manpages / debian 11 / libpam-modules / pam_ftp.8.en
PAM_FTP(8) Linux-PAM Manual PAM_FTP(8)

pam_ftp - PAM module for anonymous access module

pam_ftp.so [debug] [ignore] [users=XXX,YYY,...]

pam_ftp is a PAM module which provides a pluggable anonymous ftp mode of access.

This module intercepts the user's name and password. If the name is ftp or anonymous, the user's password is broken up at the @ delimiter into a PAM_RUSER and a PAM_RHOST part; these pam-items being set accordingly. The username (PAM_USER) is set to ftp. In this case the module succeeds. Alternatively, the module sets the PAM_AUTHTOK item with the entered password and fails.

This module is not safe and easily spoofable.

debug

Print debug information.

ignore

Pay no attention to the email address of the user (if supplied).

ftp=XXX,YYY,...

Instead of ftp or anonymous, provide anonymous login to the comma separated list of users: XXX,YYY,.... Should the applicant enter one of these usernames the returned username is set to the first in the list: XXX.

Only the auth module type is provided.

PAM_SUCCESS

The authentication was successful.

PAM_USER_UNKNOWN

User not known.

Add the following line to /etc/pam.d/ftpd to handle ftp style anonymous login:

#
# ftpd; add ftp-specifics. These lines enable anonymous ftp over
#       standard UN*X access (the listfile entry blocks access to
#       users listed in /etc/ftpusers)
#
auth    sufficient  pam_ftp.so
auth    required    pam_unix.so use_first_pass
auth    required    pam_listfile.so \

onerr=succeed item=user sense=deny file=/etc/ftpusers

pam.conf(5), pam.d(5), pam(7)

pam_ftp was written by Andrew G. Morgan <morgan@kernel.org>.

06/08/2020 Linux-PAM Manual