1PAM_TALLY2(8)                  Linux-PAM Manual                  PAM_TALLY2(8)
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NAME

6       pam_tally2 - The login counter (tallying) module
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SYNOPSIS

9       pam_tally2.so [file=/path/to/counter] [onerr=[fail|succeed]]
10                     [magic_root] [even_deny_root] [deny=n] [lock_time=n]
11                     [unlock_time=n] [root_unlock_time=n] [serialize] [audit]
12                     [silent] [no_log_info] [debug]
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14       pam_tally2 [--file /path/to/counter] [--user username] [--reset[=n]]
15                  [--quiet]
16

DESCRIPTION

18       This module maintains a count of attempted accesses, can reset count on
19       success, can deny access if too many attempts fail.
20
21       pam_tally2 comes in two parts: pam_tally2.so and pam_tally2. The former
22       is the PAM module and the latter, a stand-alone program.  pam_tally2 is
23       an (optional) application which can be used to interrogate and
24       manipulate the counter file. It can display user counts, set individual
25       counts, or clear all counts. Setting artificially high counts may be
26       useful for blocking users without changing their passwords. For
27       example, one might find it useful to clear all counts every midnight
28       from a cron job.
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30       Normally, failed attempts to access root will not cause the root
31       account to become blocked, to prevent denial-of-service: if your users
32       aren't given shell accounts and root may only login via su or at the
33       machine console (not telnet/rsh, etc), this is safe.
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OPTIONS

36       GLOBAL OPTIONS
37           This can be used for auth and account module types.
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39           onerr=[fail|succeed]
40               If something weird happens (like unable to open the file),
41               return with PAM_SUCCESS if onerr=succeed is given, else with
42               the corresponding PAM error code.
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44           file=/path/to/counter
45               File where to keep counts. Default is /var/log/tallylog.
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47           audit
48               Will log the user name into the system log if the user is not
49               found.
50
51           silent
52               Don't print informative messages.
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54           no_log_info
55               Don't log informative messages via syslog(3).
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57           debug
58               Always log tally count when it is incremented as a debug level
59               message to the system log.
60
61       AUTH OPTIONS
62           Authentication phase first increments attempted login counter and
63           checks if user should be denied access. If the user is
64           authenticated and the login process continues on call to
65           pam_setcred(3) it resets the attempts counter.
66
67           deny=n
68               Deny access if tally for this user exceeds n.
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70           lock_time=n
71               Always deny for n seconds after failed attempt.
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73           unlock_time=n
74               Allow access after n seconds after failed attempt. If this
75               option is used the user will be locked out for the specified
76               amount of time after he exceeded his maximum allowed attempts.
77               Otherwise the account is locked until the lock is removed by a
78               manual intervention of the system administrator.
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80           magic_root
81               If the module is invoked by a user with uid=0 the counter is
82               not incremented. The sysadmin should use this for user launched
83               services, like su, otherwise this argument should be omitted.
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85           even_deny_root
86               Root account can become unavailable.
87
88           root_unlock_time=n
89               This option implies even_deny_root option. Allow access after n
90               seconds to root account after failed attempt. If this option is
91               used the root user will be locked out for the specified amount
92               of time after he exceeded his maximum allowed attempts.
93
94           serialize
95               Serialize access to the tally file using locks. This option
96               might be used only for non-multithreaded services because it
97               depends on the fcntl locking of the tally file. Also it is a
98               good idea to use this option only in such configurations where
99               the time between auth phase and account or setcred phase is not
100               dependent on the authenticating client. Otherwise the
101               authenticating client will be able to prevent simultaneous
102               authentications by the same user by simply artificially
103               prolonging the time the file record lock is held.
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105       ACCOUNT OPTIONS
106           Account phase resets attempts counter if the user is not magic
107           root. This phase can be used optionally for services which don't
108           call pam_setcred(3) correctly or if the reset should be done
109           regardless of the failure of the account phase of other modules.
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111           magic_root
112               If the module is invoked by a user with uid=0 the counter is
113               not changed. The sysadmin should use this for user launched
114               services, like su, otherwise this argument should be omitted.
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MODULE TYPES PROVIDED

117       The auth and account module types are provided.
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RETURN VALUES

120       PAM_AUTH_ERR
121           A invalid option was given, the module was not able to retrieve the
122           user name, no valid counter file was found, or too many failed
123           logins.
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125       PAM_SUCCESS
126           Everything was successful.
127
128       PAM_USER_UNKNOWN
129           User not known.
130

NOTES

132       pam_tally2 is not compatible with the old pam_tally faillog file
133       format. This is caused by requirement of compatibility of the tallylog
134       file format between 32bit and 64bit architectures on multiarch systems.
135
136       There is no setuid wrapper for access to the data file such as when the
137       pam_tally2.so module is called from xscreensaver. As this would make it
138       impossible to share PAM configuration with such services the following
139       workaround is used: If the data file cannot be opened because of
140       insufficient permissions (EACCES) the module returns PAM_IGNORE.
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EXAMPLES

143       Add the following line to /etc/pam.d/login to lock the account after 4
144       failed logins. Root account will be locked as well. The accounts will
145       be automatically unlocked after 20 minutes. The module does not have to
146       be called in the account phase because the login calls pam_setcred(3)
147       correctly.
148
149           auth     required       pam_securetty.so
150           auth     required       pam_tally2.so deny=4 even_deny_root unlock_time=1200
151           auth     required       pam_env.so
152           auth     required       pam_unix.so
153           auth     required       pam_nologin.so
154           account  required       pam_unix.so
155           password required       pam_unix.so
156           session  required       pam_limits.so
157           session  required       pam_unix.so
158           session  required       pam_lastlog.so nowtmp
159           session  optional       pam_mail.so standard
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161

FILES

163       /var/log/tallylog
164           failure count logging file
165

SEE ALSO

167       pam.conf(5), pam.d(5), pam(8)
168

AUTHOR

170       pam_tally2 was written by Tim Baverstock and Tomas Mraz.
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174Linux-PAM Manual                  05/18/2017                     PAM_TALLY2(8)
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