xref: /freebsd/lib/libpam/modules/pam_unix/pam_unix.8 (revision 830940567b49bb0c08dfaed40418999e76616909)
1.\" Copyright (c) 2001 Mark R V Murray
2.\" All rights reserved.
3.\" Copyright (c) 2001 Networks Associates Technology, Inc.
4.\" All rights reserved.
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6.\" This software was developed for the FreeBSD Project by ThinkSec AS and
7.\" NAI Labs, the Security Research Division of Network Associates, Inc.
8.\" under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
9.\" DARPA CHATS research program.
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35.\" $FreeBSD$
36.\"
37.Dd June 20, 2009
38.Dt PAM_UNIX 8
39.Os
40.Sh NAME
41.Nm pam_unix
42.Nd UNIX PAM module
43.Sh SYNOPSIS
44.Op Ar service-name
45.Ar module-type
46.Ar control-flag
47.Pa pam_unix
48.Op Ar options
49.Sh DESCRIPTION
50The
51.Ux
52authentication service module for PAM,
53.Nm
54provides functionality for three PAM categories:
55authentication, account management, and password management.
56In terms of the
57.Ar module-type
58parameter, they are the
59.Dq Li auth ,
60.Dq Li account ,
61and
62.Dq Li password
63features.
64It also provides a null function for session management.
65.Ss Ux Ss Authentication Module
66The
67.Ux
68authentication component provides functions to verify the identity of
69a user
70.Pq Fn pam_sm_authenticate ,
71which obtains the relevant
72.Xr passwd 5
73entry.
74It prompts the user for a password and verifies that this is correct with
75.Xr crypt 3 .
76.Pp
77The following options may be passed to the authentication module:
78.Bl -tag -width ".Cm use_first_pass"
79.It Cm debug
80.Xr syslog 3
81debugging information at
82.Dv LOG_DEBUG
83level.
84.It Cm use_first_pass
85If the authentication module is not the first in the stack, and a
86previous module obtained the user's password, that password is used to
87authenticate the user.
88If this fails, the authentication module returns failure without
89prompting the user for a password.
90This option has no effect if the authentication module is the first in
91the stack, or if no previous modules obtained the user's password.
92.It Cm try_first_pass
93This option is similar to the
94.Cm use_first_pass
95option, except that if the previously obtained password fails, the
96user is prompted for another password.
97.It Cm auth_as_self
98This option will require the user to authenticate themselves as
99themselves, not as the account they are attempting to access.
100This is primarily for services like
101.Xr su 1 ,
102where the user's ability to retype their own password might be deemed
103sufficient.
104.It Cm nullok
105If the password database has no password for the entity being
106authenticated, then this option will forgo password prompting, and
107silently allow authentication to succeed.
108.It Cm local_pass
109Use only the local password database, even if NIS is in use.
110This will cause an authentication failure if the system is configured
111to only use NIS.
112.It Cm nis_pass
113Use only the NIS password database.
114This will cause an authentication failure if the system is not
115configured to use NIS.
116.El
117.Ss Ux Ss Account Management Module
118The
119.Ux
120account management component provides a function to perform account
121management,
122.Fn pam_sm_acct_mgmt .
123The function verifies that the authenticated user is allowed to log
124into the local user account by checking the following criteria:
125.Bl -dash -offset indent
126.It
127locked status of the account compatible with
128.Xr pw 8
129.Cm lock ;
130.It
131the password expiry date from
132.Xr passwd 5 ;
133.It
134.Xr login.conf 5
135restrictions on the remote host, login time, and tty.
136.El
137.Pp
138The following options may be passed to the management module:
139.Bl -tag -width ".Cm use_first_pass"
140.It Cm debug
141.Xr syslog 3
142debugging information at
143.Dv LOG_DEBUG
144level.
145.El
146.Ss Ux Ss Password Management Module
147The
148.Ux
149password management component provides a function to perform password
150management,
151.Fn pam_sm_chauthtok .
152The function changes
153the user's password.
154.Pp
155The following options may be passed to the password module:
156.Bl -tag -width ".Cm use_first_pass"
157.It Cm debug
158.Xr syslog 3
159debugging information at
160.Dv LOG_DEBUG
161level.
162.It Cm no_warn
163suppress warning messages to the user.
164These messages include reasons why the user's authentication attempt
165was declined.
166.It Cm local_pass
167forces the password module to change a local password in favour of a
168NIS one.
169.It Cm nis_pass
170forces the password module to change a NIS password in favour of a
171local one.
172.El
173.Sh FILES
174.Bl -tag -width ".Pa /etc/master.passwd" -compact
175.It Pa /etc/master.passwd
176default
177.Ux
178password database.
179.El
180.Sh SEE ALSO
181.Xr passwd 1 ,
182.Xr getlogin 2 ,
183.Xr crypt 3 ,
184.Xr getpwent 3 ,
185.Xr syslog 3 ,
186.Xr nsswitch.conf 5 ,
187.Xr passwd 5 ,
188.Xr pam 8 ,
189.Xr pw 8 ,
190.Xr yp 8
191