From 9ada0093e92388590c7368600ca4e9e3e376f0d0 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 16:22:51 +0200 Subject: Adding upstream version 1.5.2. Signed-off-by: Daniel Baumann --- modules/pam_listfile/README | 101 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 101 insertions(+) create mode 100644 modules/pam_listfile/README (limited to 'modules/pam_listfile/README') diff --git a/modules/pam_listfile/README b/modules/pam_listfile/README new file mode 100644 index 0000000..5f926bd --- /dev/null +++ b/modules/pam_listfile/README @@ -0,0 +1,101 @@ +pam_listfile — deny or allow services based on an arbitrary file + +━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ + +DESCRIPTION + +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 + +item=[tty|user|rhost|ruser|group|shell] + + What is listed in the file and should be checked for. + +sense=[allow|deny] + + Action to take if found in file, if the item is NOT found in the file, then + the opposite action is requested. + +file=/path/filename + + File containing one item per line. The file needs to be a plain file and + not world writable. + +onerr=[succeed|fail] + + What to do if something weird happens like being unable to open the file. + +apply=[user|@group] + + 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. + +quiet + + Do not treat service refusals or missing list files as errors that need to + be logged. + +EXAMPLES + +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 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 account. + +AUTHOR + +pam_listfile was written by Michael K. Johnson and Elliot +Lee . + -- cgit v1.2.3