1.\" Copyright (c) 1988, 1990, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" @(#)chpass.1 8.2 (Berkeley) 12/30/93 29.\" 30.Dd May 25, 2021 31.Dt CHPASS 1 32.Os 33.Sh NAME 34.Nm chpass , 35.Nm chfn , 36.Nm chsh , 37.Nm ypchpass , 38.Nm ypchfn , 39.Nm ypchsh 40.Nd add or change user database information 41.Sh SYNOPSIS 42.Nm chpass 43.Op Fl a Ar list 44.Op Fl e Ar expiretime 45.Op Fl p Ar encpass 46.Op Fl s Ar newshell 47.Op user 48.Nm ypchpass 49.Op Fl loy 50.Op Fl a Ar list 51.Op Fl d Ar domain 52.Op Fl e Ar expiretime 53.Op Fl h Ar host 54.Op Fl p Ar encpass 55.Op Fl s Ar newshell 56.Op user 57.Sh DESCRIPTION 58The 59.Nm 60utility 61allows editing of the user database information associated 62with 63.Ar user 64or, by default, the current user. 65.Pp 66The 67.Nm chfn , 68.Nm chsh , 69.Nm ypchpass , 70.Nm ypchfn 71and 72.Nm ypchsh 73utilities behave identically to 74.Nm . 75(There is only one program.) 76.Pp 77The information is formatted and supplied to an editor for changes. 78.Pp 79Only the information that the user is allowed to change is displayed. 80.Pp 81The options are as follows: 82.Bl -tag -width "-e expiretime" 83.It Fl a Ar list 84The super-user is allowed to directly supply a user database 85entry, in the format specified by 86.Xr passwd 5 , 87as an argument. 88This argument must be a colon 89.Pq Dq \&: 90separated list of all the 91user database fields, although they may be empty. 92.It Fl e Ar expiretime 93Change the account expire time. 94This option is used to set the expire time 95from a script as if it was done in the interactive editor. 96.It Fl p Ar encpass 97The super-user is allowed to directly supply an encrypted password field, 98in the format used by 99.Xr crypt 3 , 100as an argument. 101.It Fl s Ar newshell 102Attempt to change the user's shell to 103.Ar newshell . 104.El 105.Pp 106Possible display items are as follows: 107.Pp 108.Bl -tag -width "Other Information:" -compact -offset indent 109.It Login: 110user's login name 111.It Password: 112user's encrypted password 113.It Uid: 114user's login 115.It Gid: 116user's login group 117.It Class: 118user's general classification 119.It Change: 120password change time 121.It Expire: 122account expiration time 123.It Full Name: 124user's real name 125.It Office Location: 126user's office location (1) 127.It Office Phone: 128user's office phone (1) 129.It Home Phone: 130user's home phone (1) 131.It Other Information: 132any locally defined parameters for user (1) 133.It Home Directory: 134user's home directory 135.It Shell: 136user's login shell 137.Pp 138.It NOTE(1) - 139In the actual master.passwd file, these fields are comma-delimited 140fields embedded in the FullName field. 141.El 142.Pp 143The 144.Ar login 145field is the user name used to access the computer account. 146.Pp 147The 148.Ar password 149field contains the encrypted form of the user's password. 150.Pp 151The 152.Ar uid 153field is the number associated with the 154.Ar login 155field. 156Both of these fields should be unique across the system (and often 157across a group of systems) as they control file access. 158.Pp 159While it is possible to have multiple entries with identical login names 160and/or identical user id's, it is usually a mistake to do so. 161Routines 162that manipulate these files will often return only one of the multiple 163entries, and that one by random selection. 164.Pp 165The 166.Ar gid 167field is the group that the user will be placed in at login. 168Since 169.Bx 170supports multiple groups (see 171.Xr groups 1 ) 172this field currently has little special meaning. 173This field may be filled in with either a number or a group name (see 174.Xr group 5 ) . 175.Pp 176The 177.Ar class 178field references class descriptions in 179.Pa /etc/login.conf 180and is typically used to initialize the user's system resource limits 181when they login. 182.Pp 183The 184.Ar change 185field is the date by which the password must be changed. 186.Pp 187The 188.Ar expire 189field is the date on which the account expires. 190.Pp 191Both the 192.Ar change 193and 194.Ar expire 195fields should be entered in the form 196.Dq month day year 197where 198.Ar month 199is the month name (the first three characters are sufficient), 200.Ar day 201is the day of the month, and 202.Ar year 203is the year. 204.Pp 205Five fields are available for storing the user's 206.Ar full name , office location , 207.Ar work 208and 209.Ar home telephone 210numbers and finally 211.Ar other information 212which is a single comma delimited string to represent any additional 213gecos fields (typically used for site specific user information). 214Note that 215.Xr finger 1 216will display the office location and office phone together under the 217heading 218.Ar Office\&: . 219.Pp 220The user's 221.Ar home directory 222is the full 223.Ux 224path name where the user 225will be placed at login. 226.Pp 227The 228.Ar shell 229field is the command interpreter the user prefers. 230If the 231.Ar shell 232field is empty, the Bourne shell, 233.Pa /bin/sh , 234is assumed. 235When altering a login shell, and not the super-user, the user 236may not change from a non-standard shell or to a non-standard 237shell. 238Non-standard is defined as a shell not found in 239.Pa /etc/shells . 240.Pp 241Once the information has been verified, 242.Nm 243uses 244.Xr pwd_mkdb 8 245to update the user database. 246.Sh ENVIRONMENT 247The 248.Xr vi 1 249editor will be used unless the environment variable 250.Ev EDITOR 251is set to 252an alternate editor. 253When the editor terminates, the information is re-read and used to 254update the user database itself. 255Only the user, or the super-user, may edit the information associated 256with the user. 257.Pp 258See 259.Xr pwd_mkdb 8 260for an explanation of the impact of setting the 261.Ev PW_SCAN_BIG_IDS 262environment variable. 263.Sh NIS INTERACTION 264The 265.Nm 266utility can also be used in conjunction with NIS, however some restrictions 267apply. 268Currently, 269.Nm 270can only make changes to the NIS passwd maps through 271.Xr rpc.yppasswdd 8 , 272which normally only permits changes to a user's password, shell and GECOS 273fields. 274Except when invoked by the super-user on the NIS master server, 275.Nm 276(and, similarly, 277.Xr passwd 1 ) 278cannot use the 279.Xr rpc.yppasswdd 8 280server to change other user information or 281add new records to the NIS passwd maps. 282Furthermore, 283.Xr rpc.yppasswdd 8 284requires password authentication before it will make any 285changes. 286The only user allowed to submit changes without supplying 287a password is the super-user on the NIS master server; all other users, 288including those with root privileges on NIS clients (and NIS slave 289servers) must enter a password. 290(The super-user on the NIS master is allowed to bypass these restrictions 291largely for convenience: a user with root access 292to the NIS master server already has the privileges required to make 293updates to the NIS maps, but editing the map source files by hand can 294be cumbersome. 295.Pp 296Note: these exceptions only apply when the NIS master server is a 297.Fx 298system). 299.Pp 300Consequently, except where noted, the following restrictions apply when 301.Nm 302is used with NIS: 303.Bl -enum -offset indent 304.It 305.Em "Only the shell and GECOS information may be changed" . 306All other 307fields are restricted, even when 308.Nm 309is invoked by the super-user. 310While support for 311changing other fields could be added, this would lead to 312compatibility problems with other NIS-capable systems. 313Even though the super-user may supply data for other fields 314while editing an entry, the extra information (other than the 315password \(em see below) will be silently discarded. 316.Pp 317Exception: the super-user on the NIS master server is permitted to 318change any field. 319.It 320.Em "Password authentication is required" . 321The 322.Nm 323utility will prompt for the user's NIS password before effecting 324any changes. 325If the password is invalid, all changes will be 326discarded. 327.Pp 328Exception: the super-user on the NIS master server is allowed to 329submit changes without supplying a password. 330(The super-user may 331choose to turn off this feature using the 332.Fl o 333flag, described below.) 334.It 335.Em "Adding new records to the local password database is discouraged" . 336The 337.Nm 338utility will allow the administrator to add new records to the 339local password database while NIS is enabled, but this can lead to 340some confusion since the new records are appended to the end of 341the master password file, usually after the special NIS '+' entries. 342The administrator should use 343.Xr vipw 8 344to modify the local password 345file when NIS is running. 346.Pp 347The super-user on the NIS master server is permitted to add new records 348to the NIS password maps, provided the 349.Xr rpc.yppasswdd 8 350server has been started with the 351.Fl a 352flag to permitted additions (it refuses them by default). 353The 354.Nm 355utility tries to update the local password database by default; to update the 356NIS maps instead, invoke chpass with the 357.Fl y 358flag. 359.It 360.Em "Password changes are not permitted". 361Users should use 362.Xr passwd 1 363or 364.Xr yppasswd 1 365to change their NIS passwords. 366The super-user is allowed to specify 367a new password (even though the 368.Dq Password: 369field does not show 370up in the editor template, the super-user may add it back by hand), 371but even the super-user must supply the user's original password 372otherwise 373.Xr rpc.yppasswdd 8 374will refuse to update the NIS maps. 375.Pp 376Exception: the super-user on the NIS master server is permitted to 377change a user's NIS password with 378.Nm . 379.El 380.Pp 381There are also a few extra option flags that are available when 382.Nm 383is compiled with NIS support: 384.Bl -tag -width "-d domain" 385.It Fl d Ar domain 386Specify a particular NIS domain. 387The 388.Nm 389utility uses the system domain name by default, as set by the 390.Xr domainname 1 391utility. 392The 393.Fl d 394option can be used to override a default, or to specify a domain 395when the system domain name is not set. 396.It Fl h Ar host 397Specify the name or address of an NIS server to query. 398Normally, 399.Nm 400will communicate with the NIS master host specified in the 401.Pa master.passwd 402or 403.Pa passwd 404maps. 405On hosts that have not been configured as NIS clients, there is 406no way for the program to determine this information unless the user 407provides the hostname of a server. 408Note that the specified hostname need 409not be that of the NIS master server; the name of any server, master or 410slave, in a given NIS domain will do. 411.Pp 412When using the 413.Fl d 414option, the hostname defaults to 415.Dq localhost . 416The 417.Fl h 418option can be used in conjunction with the 419.Fl d 420option, in which case the user-specified hostname will override 421the default. 422.It Fl l 423Force 424.Nm 425to modify the local copy of a user's password 426information in the event that a user exists in both 427the local and NIS databases. 428.It Fl o 429Force the use of RPC-based updates when communicating with 430.Xr rpc.yppasswdd 8 431.Pq Dq old-mode . 432When invoked by the super-user on the NIS master server, 433.Nm 434allows unrestricted changes to the NIS passwd maps using dedicated, 435non-RPC-based mechanism (in this case, a 436.Ux 437domain socket). 438The 439.Fl o 440flag can be used to force 441.Nm 442to use the standard update mechanism instead. 443This option is provided 444mainly for testing purposes. 445.It Fl y 446Opposite effect of 447.Fl l . 448This flag is largely redundant since 449.Nm 450operates on NIS entries by default if NIS is enabled. 451.El 452.Sh FILES 453.Bl -tag -width /etc/master.passwd -compact 454.It Pa /etc/master.passwd 455the user database 456.It Pa /etc/passwd 457a Version 7 format password file 458.It Pa /etc/pw.XXXXXX 459temporary file 460.It Pa /etc/shells 461the list of approved shells 462.El 463.Sh EXAMPLES 464Change the shell of the current user to 465.Ql /usr/local/bin/zsh : 466.Bd -literal -offset indent 467chsh -s /usr/local/bin/zsh 468.Ed 469.Sh SEE ALSO 470.Xr finger 1 , 471.Xr login 1 , 472.Xr passwd 1 , 473.Xr getusershell 3 , 474.Xr login.conf 5 , 475.Xr passwd 5 , 476.Xr pw 8 , 477.Xr pwd_mkdb 8 , 478.Xr vipw 8 479.Rs 480.%A Robert Morris 481.%A Ken Thompson 482.%T "UNIX Password security" 483.Re 484.Sh HISTORY 485The 486.Nm 487utility appeared in 488.Bx 4.3 Reno . 489.Sh BUGS 490User information should (and eventually will) be stored elsewhere. 491