pam_listfile is a PAM module which provides a way to deny or allow
services based on an arbitrary file.
The module gets the item of the type specified -- user specifies the
username, PAM_USER; tty specifies the name of the terminal over which
the request has been made, PAM_TTY; rhost specifies the name of the
remote host (if any) from which the request was made, PAM_RHOST; and
ruser specifies the name of the remote user (if available) who made
the request, PAM_RUSER -- and looks for an instance of that item in
the file=filename. filename contains one line per item listed. If
the item is found, then if sense=allow, PAM_SUCCESS is returned,
causing the authorization request to succeed; else if sense=deny,
PAM_AUTH_ERR is returned, causing the authorization request to fail.
If an error is encountered (for instance, if filename does not exist,
or a poorly-constructed argument is encountered), then if
onerr=succeed, PAM_SUCCESS is returned, otherwise if onerr=fail,
PAM_AUTH_ERR or PAM_SERVICE_ERR (as appropriate) will be returned.
An additional argument, apply=, can be used to restrict the
application of the above to a specific user (apply=username) or a
given group (apply=@groupname). This added restriction is only
meaningful when used with the tty, rhost and shell items.
Besides this last one, all arguments should be specified; do not
count on any default behavior.
No credentials are awarded by this module.
What is listed in the file and should be checked for.
Action to take if found in file, if the item is NOT found in the
file, then the opposite action is requested.
File containing one item per line. The file needs to be a plain
file and not world writable.
What to do if something weird happens like being unable to open
Restrict the user class for which the restriction apply. Note
that with item=[user|ruser|group] this does not make sense, but
for item=[tty|rhost|shell] it have a meaning.
Do not treat service refusals or missing list files as errors
that need to be logged.
Classic 'ftpusers' authentication can be implemented with this entry
# deny ftp-access to users listed in the /etc/ftpusers file
auth required pam_listfile.so \
onerr=succeed item=user sense=deny file=/etc/ftpusers
Note, users listed in /etc/ftpusers file are (counterintuitively) not
allowed access to the ftp service.
To allow login access only for certain users, you can use a
/etc/pam.d/login entry like this:
# permit login to users listed in /etc/loginusers
auth required pam_listfile.so \
onerr=fail item=user sense=allow file=/etc/loginusers
For this example to work, all users who are allowed to use the login
service should be listed in the file /etc/loginusers. Unless you are
explicitly trying to lock out root, make sure that when you do this,
you leave a way for root to log in, either by listing root in
/etc/loginusers, or by listing a user who is able to su to the root
This page is part of the linux-pam (Pluggable Authentication Modules
for Linux) project. Information about the project can be found at
⟨http://www.linux-pam.org/⟩. If you have a bug report for this manual
page, see ⟨//www.linux-pam.org/⟩. This page was obtained from the
tarball Linux-PAM-1.3.0.tar.bz2 fetched from
⟨http://www.linux-pam.org/library/⟩ on 2020-08-13. If you discover
any rendering problems in this HTML version of the page, or you
believe there is a better or more up-to-date source for the page, or
you have corrections or improvements to the information in this
COLOPHON (which is not part of the original manual page), send a mail
Linux-PAM Manual 04/01/2016 PAM_LISTFILE(8)