xref: /openbsd-src/usr.bin/passwd/passwd.1 (revision 41ce3b17e73f6b7d2d9e1a3d961e4bab2d895cb5)
1.\"	$OpenBSD: passwd.1,v 1.48 2022/03/31 17:27:26 naddy Exp $
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30.\"	from: @(#)passwd.1	6.11 (Berkeley) 7/24/91
31.\"
32.Dd $Mdocdate: March 31 2022 $
33.Dt PASSWD 1
34.Os
35.Sh NAME
36.Nm passwd
37.Nd modify a user's password
38.Sh SYNOPSIS
39.Nm passwd
40.Op Ar user
41.Sh DESCRIPTION
42.Nm
43changes the user's password.
44If no
45.Ar user
46is specified, the user's login name is used (see
47.Xr logname 1 ) .
48First, the user is prompted for their current password.
49If the current password is correctly typed, a new password is requested.
50The new password must be entered twice to avoid typing errors.
51.Pp
52The new password should be at least six characters long and not
53purely alphabetic.
54A mixture of both lower and uppercase letters, numbers, and
55meta-characters is encouraged.
56.Pp
57The quality of the password can be enforced by specifying an external
58checking program via the
59.Dq passwordcheck
60variable in
61.Xr login.conf 5 .
62.Pp
63The superuser is not required to provide a user's current password
64if only the local password is modified.
65.Pp
66Password encryption parameters depend on the configuration of the
67.Dq localcipher
68capability in
69.Xr login.conf 5 .
70If none is specified then blowfish is used, with the number of
71rounds selected based on system performance.
72.Sh FILES
73.Bl -tag -width /etc/master.passwd -compact
74.It Pa /etc/login.conf
75configuration options
76.It Pa /etc/master.passwd
77user database
78.It Pa /etc/passwd
79user database, with confidential information removed
80.It Pa /etc/passwd.XXXXXX
81temporary copy of the password file
82.It Pa /etc/ptmp
83lock file for the passwd database
84.El
85.Sh DIAGNOSTICS
86.Bl -diag
87.It "Attempting to lock password file, please wait or press ^C to abort"
88.Pp
89The password file is currently locked by another process;
90.Nm
91will keep trying to lock the password file until it succeeds or
92you hit the interrupt character (control-C by default).
93If
94.Nm
95is interrupted while trying to gain the lock, the password change will
96be lost.
97.Pp
98If the process holding the lock was prematurely terminated, the lock
99file may be stale and
100.Nm
101will wait forever trying to lock the password file.
102To determine whether a live process is actually holding the lock, the
103admin may run the following:
104.Bd -literal -offset indent
105$ fstat /etc/ptmp
106.Ed
107.Pp
108If no process is listed, it is safe to remove the
109.Pa /etc/ptmp
110file to clear the error.
111.El
112.Sh SEE ALSO
113.Xr chpass 1 ,
114.Xr encrypt 1 ,
115.Xr logname 1 ,
116.Xr login.conf 5 ,
117.Xr passwd 5 ,
118.Xr pwd_mkdb 8 ,
119.Xr vipw 8
120.Rs
121.%A Robert Morris
122.%A Ken Thompson
123.%T Password security: a case history
124.%J Communications of the ACM
125.%V Volume 22
126.%N Issue 11
127.%D Nov. 1979
128.%P pp. 594\(en597
129.Re
130.Sh HISTORY
131A
132.Nm
133command appeared in
134.At v3 .
135