PAM_FTP(8) Linux-PAM Manual PAM_FTP(8)NAME
pam_ftp - PAM module for anonymous access module
SYNOPSIS
pam_ftp.so [debug] [ignore] [users=XXX,YYY,...]
DESCRIPTION
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.
OPTIONS
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.
MODULE TYPES PROVIDED
Only the auth module type is provided.
RETURN VALUES
PAM_SUCCESS
The authentication was successful.
PAM_USER_UNKNOWN
User not known.
EXAMPLES
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
SEE ALSO pam.conf(5), pam.d(5), pam(7)AUTHOR
pam_ftp was written by Andrew G. Morgan <morgan@kernel.org>.
Linux-PAM Manual 06/04/2011 PAM_FTP(8)
Check Out this Related Man Page
PAM_LISTFILE(8) Linux-PAM Manual PAM_LISTFILE(8)NAME
pam_listfile - deny or allow services based on an arbitrary file
SYNOPSIS
pam_listfile.so item=[tty|user|rhost|ruser|group|shell] sense=[allow|deny] file=/path/filename onerr=[succeed|fail] [apply=[user|@group]]
[quiet]
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.
MODULE TYPES PROVIDED
All module types (auth, account, password and session) are provided.
RETURN VALUES
PAM_AUTH_ERR
Authentication failure.
PAM_BUF_ERR
Memory buffer error.
PAM_IGNORE
The rule does not apply to the apply option.
PAM_SERVICE_ERR
Error in service module.
PAM_SUCCESS
Success.
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.
SEE ALSO pam.conf(5), pam.d(5), pam(7)AUTHOR
pam_listfile was written by Michael K. Johnson <johnsonm@redhat.com> and Elliot Lee <sopwith@cuc.edu>.
Linux-PAM Manual 06/04/2011 PAM_LISTFILE(8)