pam_listfile(8) — Linux manual page


PAM_LISTFILE(8)               Linux-PAM Manual               PAM_LISTFILE(8)

NAME         top

       pam_listfile - deny or allow services based on an arbitrary file

SYNOPSIS         top item=[tty|user|rhost|ruser|group|shell]
                       sense=[allow|deny] file=/path/filename
                       onerr=[succeed|fail] [apply=[user|@group]] [quiet]

DESCRIPTION         top

       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.

OPTIONS         top

           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
           the file.

           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.


       All module types (auth, account, password and session) are provided.

RETURN VALUES         top

           Authentication failure.

           Memory buffer error.

           The rule does not apply to the apply option.

           Error in service module.


EXAMPLES         top

       Classic 'ftpusers' authentication can be implemented with this entry
       in /etc/pam.d/ftpd:

           # deny ftp-access to users listed in the /etc/ftpusers file
           auth    required \
                   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 \
                   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

SEE ALSO         top

       pam.conf(5), pam.d(5), pam(8)

AUTHOR         top

       pam_listfile was written by Michael K. Johnson <>
       and Elliot Lee <>.

COLOPHON         top

       This page is part of the linux-pam (Pluggable Authentication Modules
       for Linux) project.  Information about the project can be found at 
       ⟨⟩.  If you have a bug report for this manual
       page, see ⟨//⟩.  This page was obtained from the
       tarball Linux-PAM-1.3.0.tar.bz2 fetched from
       ⟨⟩ on 2020-11-01.  If you discover
       any rendering problems in this HTML version of the page, or you be‐
       lieve 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)