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NAME

       pam_tally - The login counter (tallying) module

SYNOPSIS

       pam_tally.so [file=/path/to/counter] [onerr=[fail|succeed]]
                    [magic_root] [even_deny_root_account] [deny=n]
                    [lock_time=n] [unlock_time=n] [per_user] [no_lock_time]
                    [no_reset] [audit] [silent] [no_log_info]

       pam_tally [--file /path/to/counter] [--user username] [--reset[=n]]
                 [--quiet]

DESCRIPTION

       This module maintains a count of attempted accesses, can reset count on
       success, can deny access if too many attempts fail.

       pam_tally comes in two parts: pam_tally.so and pam_tally. The former is
       the PAM module and the latter, a stand-alone program.  pam_tally is an
       (optional) application which can be used to interrogate and manipulate
       the counter file. It can display users' counts, set individual counts,
       or clear all counts. Setting artificially high counts may be useful for
       blocking users without changing their passwords. For example, one might
       find it useful to clear all counts every midnight from a cron job. The
       faillog(8) command can be used instead of pam_tally to to maintain the
       counter file.

       Normally, failed attempts to access root will not cause the root
       account to become blocked, to prevent denial-of-service: if your users
       aren't given shell accounts and root may only login via su or at the
       machine console (not telnet/rsh, etc), this is safe.

OPTIONS

       GLOBAL OPTIONS
           This can be used for auth and account module types.

           onerr=[fail|succeed]
               If something weird happens (like unable to open the file),
               return with PAM_SUCCESS if onerr=succeed is given, else with
               the corresponding PAM error code.

           file=/path/to/counter
               File where to keep counts. Default is /var/log/faillog.

           audit
               Will log the user name into the system log if the user is not
               found.

           silent
               Don't print informative messages.

           no_log_info
               Don't log informative messages via syslog(3).

       AUTH OPTIONS
           Authentication phase first checks if user should be denied access
           and if not it increments attempted login counter. Then on call to
           pam_setcred(3) it resets the attempts counter.

           deny=n
               Deny access if tally for this user exceeds n.

           lock_time=n
               Always deny for n seconds after failed attempt.

           unlock_time=n
               Allow access after n seconds after failed attempt. If this
               option is used the user will be locked out for the specified
               amount of time after he exceeded his maximum allowed attempts.
               Otherwise the account is locked until the lock is removed by a
               manual intervention of the system administrator.

           magic_root
               If the module is invoked by a user with uid=0 the counter is
               not incremented. The sysadmin should use this for user launched
               services, like su, otherwise this argument should be omitted.

           no_lock_time
               Do not use the .fail_locktime field in /var/log/faillog for
               this user.

           no_reset
               Don't reset count on successful entry, only decrement.

           even_deny_root_account
               Root account can become unavailable.

           per_user
               If /var/log/faillog contains a non-zero
               .fail_max/.fail_locktime field for this user then use it
               instead of deny=n/ lock_time=n parameter.

           no_lock_time
               Don't use .fail_locktime filed in /var/log/faillog for this
               user.

       ACCOUNT OPTIONS
           Account phase resets attempts counter if the user is not magic
           root. This phase can be used optionally for services which don't
           call pam_setcred(3) correctly or if the reset should be done
           regardless of the failure of the account phase of other modules.

           magic_root
               If the module is invoked by a user with uid=0 the counter is
               not incremented. The sysadmin should use this for user launched
               services, like su, otherwise this argument should be omitted.

           no_reset
               Don't reset count on successful entry, only decrement.

MODULE TYPES PROVIDED

       The auth and account module types are provided.

RETURN VALUES

       PAM_AUTH_ERR
           A invalid option was given, the module was not able to retrieve the
           user name, no valid counter file was found, or too many failed
           logins.

       PAM_SUCCESS
           Everything was successful.

       PAM_USER_UNKNOWN
           User not known.

EXAMPLES

       Add the following line to /etc/pam.d/login to lock the account after
       too many failed logins. The number of allowed fails is specified by
       /var/log/faillog and needs to be set with pam_tally or faillog(8)
       before.

           auth     required       pam_securetty.so
           auth     required       pam_tally.so per_user
           auth     required       pam_env.so
           auth     required       pam_unix.so
           auth     required       pam_nologin.so
           account  required       pam_unix.so
           password required       pam_unix.so
           session  required       pam_limits.so
           session  required       pam_unix.so
           session  required       pam_lastlog.so nowtmp
           session  optional       pam_mail.so standard

FILES

       /var/log/faillog
           failure logging file

SEE ALSO

       faillog(8), pam.conf(5), pam.d(5), pam(7)

AUTHOR

       pam_tally was written by Tim Baverstock and Tomas Mraz.