1.\" $NetBSD: passwd.1,v 1.28 2006/03/07 01:52:09 hubertf Exp $ 2.\" 3.\" Copyright (c) 1990, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. Neither the name of the University nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.\" from: @(#)passwd.1 8.1 (Berkeley) 6/6/93 31.\" 32.Dd February 25, 2005 33.Dt PASSWD 1 34.Os 35.Sh NAME 36.Nm passwd 37.Nd modify a user's password 38.Sh SYNOPSIS 39.Nm 40.Op Ar user 41.Nm 42.Oo Fl d Ar files | Fl l Oc 43.Op Ar user 44.Nm 45.Oo Fl d Ar nis | Fl y Oc 46.Op Ar user 47.Nm 48.Oo Fl d Ar krb5 | Fl k Oc 49.Op Ar principal 50.Sh DESCRIPTION 51.Nm 52changes the user's password. 53First, the user is 54prompted for their current password. 55If the current password is correctly typed, a new password is 56requested. 57The new password must be entered twice to avoid typing errors. 58.Pp 59The new password should be at least six characters long and not 60purely alphabetic. 61Its total length must be less than 62.Dv _PASSWORD_LEN 63(currently 128 characters). 64Numbers, upper case letters and meta characters 65are encouraged. 66.Pp 67All options may not be available on all systems. 68.Bl -tag -width flag 69.It Fl d Ar database 70This option specifies the password database that should be updated. The 71following databases are supported: 72.Bl -tag -width files 73.It files 74This specifies that the password change should be applied to the local 75password file. 76When changing only the local password, 77.Nm 78uses 79.Xr pwd_mkdb 8 80to update the password databases. 81.It nis 82This specifies that the password change should be applied to the NIS 83password database. 84The 85.Xr rpc.yppasswdd 8 86daemon should be running on the master NIS server. 87.It krb5 88This specifies that the user's Kerberos 5 password should be changed. 89The host must be configured to use Kerberos. 90See 91.Xr krb5.conf 5 . 92.El 93.It Fl l 94This is the equivalent of 95.Fl d Ar files . 96.It Fl y 97This is the equivalent of 98.Fl d Ar nis . 99.It Fl k 100This is the equivalent of 101.Fl d Ar krb5 . 102.El 103.Pp 104If a password database is not specified, 105.Nm 106will change the password database as determined by the 107Pluggable Authentication Module 108.Pq PAM 109library. 110.Pp 111The type of cipher used to encrypt the password depends on the configuration 112in 113.Xr passwd.conf 5 . 114It can be different for local and NIS passwords. 115.Sh FILES 116.Bl -tag -width /etc/master.passwd -compact 117.It Pa /etc/master.passwd 118The user database 119.It Pa /etc/passwd 120A Version 7 format password file 121.It Pa /etc/passwd.XXXXXX 122Temporary copy of the password file 123.El 124.Sh SEE ALSO 125.Xr chpass 1 , 126.Xr login 1 , 127.Xr pwhash 1 , 128.Xr passwd 5 , 129.Xr passwd.conf 5 , 130.Xr pam 8 , 131.Xr pwd_mkdb 8 , 132.Xr vipw 8 133.Rs 134.%A Robert Morris 135.%A Ken Thompson 136.%T "UNIX password security" 137.Re 138.Sh HISTORY 139A 140.Nm 141command appeared in 142.At v6 . 143