1PAM_TALLY2(8) Linux-PAM Manual PAM_TALLY2(8)
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6 pam_tally2 - The login counter (tallying) module
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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]
13 pam_tally2 [--file /path/to/counter] [--user username] [--reset[=n]]
15 [--quiet]
16
18 This module maintains a count of attempted accesses, can reset count on
19 success, can deny access if too many attempts fail.
20 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 users' counts, set
25 individual counts, or clear all counts. Setting artificially high
26 counts may be useful for blocking users without changing their
27 passwords. For example, one might find it useful to clear all counts
28 every midnight from a cron job.
29 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.
34
36 GLOBAL OPTIONS
37 This can be used for auth and account module types.
38 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.
43 file=/path/to/counter
45 File where to keep counts. Default is /var/log/tallylog.
46 audit
48 Will log the user name into the system log if the user is not
49 found.
50 silent
52 Don't print informative messages.
53 no_log_info
55 Don't log informative messages via syslog(3).
56 AUTH OPTIONS
58 Authentication phase first increments attempted login counter and
59 checks if user should be denied access. If the user is
60 authenticated and the login process continues on call to
61 pam_setcred(3) it resets the attempts counter.
62 deny=n
64 Deny access if tally for this user exceeds n.
65 lock_time=n
67 Always deny for n seconds after failed attempt.
68 unlock_time=n
70 Allow access after n seconds after failed attempt. If this
71 option is used the user will be locked out for the specified
72 amount of time after he exceeded his maximum allowed attempts.
73 Otherwise the account is locked until the lock is removed by a
74 manual intervention of the system administrator.
75 magic_root
77 If the module is invoked by a user with uid=0 the counter is
78 not incremented. The sysadmin should use this for user launched
79 services, like su, otherwise this argument should be omitted.
80 even_deny_root
82 Root account can become unavailable.
83 root_unlock_time=n
85 This option implies even_deny_root option. Allow access after n
86 seconds to root account after failed attempt. If this option is
87 used the root user will be locked out for the specified amount
88 of time after he exceeded his maximum allowed attempts.
89 serialize
91 Serialize access to the tally file using locks. This option
92 might be used only for non-multithreaded services because it
93 depends on the fcntl locking of the tally file. Also it is a
94 good idea to use this option only in such configurations where
95 the time between auth phase and account or setcred phase is not
96 dependent on the authenticating client. Otherwise the
97 authenticating client will be able to prevent simultaneous
98 authentications by the same user by simply artificially
99 prolonging the time the file record lock is held.
100 ACCOUNT OPTIONS
102 Account phase resets attempts counter if the user is not magic
103 root. This phase can be used optionally for services which don't
104 call pam_setcred(3) correctly or if the reset should be done
105 regardless of the failure of the account phase of other modules.
106 magic_root
108 If the module is invoked by a user with uid=0 the counter is
109 not changed. The sysadmin should use this for user launched
110 services, like su, otherwise this argument should be omitted.
111
113 The auth and account module types are provided.
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116 PAM_AUTH_ERR
117 A invalid option was given, the module was not able to retrieve the
118 user name, no valid counter file was found, or too many failed
119 logins.
120 PAM_SUCCESS
122 Everything was successful.
123 PAM_USER_UNKNOWN
125 User not known.
126
128 pam_tally2 is not compatible with the old pam_tally faillog file
129 format. This is caused by requirement of compatibility of the tallylog
130 file format between 32bit and 64bit architectures on multiarch systems.
131 There is no setuid wrapper for access to the data file such as when the
133 pam_tally2.so module is called from xscreensaver. As this would make it
134 impossible to share PAM configuration with such services the following
135 workaround is used: If the data file cannot be opened because of
136 insufficient permissions (EACCES) the module returns PAM_IGNORE.
137
139 Add the following line to /etc/pam.d/login to lock the account after 4
140 failed logins. Root account will be locked as well. The accounts will
141 be automatically unlocked after 20 minutes. The module does not have to
142 be called in the account phase because the login calls pam_setcred(3)
143 correctly.
144 auth required pam_securetty.so
146 auth required pam_tally2.so deny=4 even_deny_root unlock_time=1200
147 auth required pam_env.so
148 auth required pam_unix.so
149 auth required pam_nologin.so
150 account required pam_unix.so
151 password required pam_unix.so
152 session required pam_limits.so
153 session required pam_unix.so
154 session required pam_lastlog.so nowtmp
155 session optional pam_mail.so standard
156
159 /var/log/tallylog
160 failure count logging file
161
163 pam.conf(5), pam.d(5), pam(8)
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166 pam_tally2 was written by Tim Baverstock and Tomas Mraz.
167Linux-PAM Manual 09/19/2013 PAM_TALLY2(8)