chpass/chpass.1

   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. All advertising materials mentioning features or use of this software
  13 .\"    must display the following acknowledgement:
  14 .\"     This product includes software developed by the University of
  15 .\"     California, Berkeley and its contributors.
  16 .\" 4. Neither the name of the University nor the names of its contributors
  17 .\"    may be used to endorse or promote products derived from this software
  18 .\"    without specific prior written permission.
  19 .\"
  20 .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  21 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23 .\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  24 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30 .\" SUCH DAMAGE.
  31 .\"
  32 .\"     @(#)chpass.1    8.2 (Berkeley) 12/30/93
  33 .\"
  34 .Dd December 30, 1993
  35 .Dt CHPASS 1
  36 .Os
  37 .Sh NAME
  38 .Nm chpass, chfn, chsh, ypchpass, ypchfn, ypchsh
  39 .Nd add or change user database information
  40 .Sh SYNOPSIS
  41 chpass
  42 .Op Fl a Ar list
  43 .Op Fl p Ar encpass
  44 .Op Fl s Ar newshell
  45 .Op user
  46 .Sh DESCRIPTION
  47 The
  48 .Nm chpass
  49 program
  50 allows editing of the user database information associated
  51 with
  52 .Ar user
  53 or, by default, the current user.
  54 The information is formatted and supplied to an editor for changes.
  55 .Pp
  56 Only the information that the user is allowed to change is displayed.
  57 .Pp
  58 The options are as follows:
  59 .Bl -tag -width flag
  60 .It Fl a
  61 The super-user is allowed to directly supply a user database
  62 entry, in the format specified by
  63 .Xr passwd 5 ,
  64 as an argument.
  65 This argument must be a colon (``:'') separated list of all the
  66 user database fields, although they may be empty.
  67 .It Fl p
  68 The super-user is allowed to directly supply an encrypted password field,
  69 in the format used by
  70 .Xr crypt 3 ,
  71 as an argument.
  72 .It Fl s
  73 The
  74 .Fl s
  75 option attempts to change the user's shell to
  76 .Ar newshell .
  77 .El
  78 .Pp
  79 Possible display items are as follows:
  80 .Pp
  81 .Bl -tag -width "Home Directory:" -compact -offset indent
  82 .It Login:
  83 user's login name
  84 .It Password:
  85 user's encrypted password
  86 .It Uid:
  87 user's login
  88 .It Gid:
  89 user's login group
  90 .It Change:
  91 password change time
  92 .It Expire:
  93 account expiration time
  94 .It Class:
  95 user's general classification
  96 .It Home Directory:
  97 user's home directory
  98 .It Shell:
  99 user's login shell
 100 .It Full Name:
 101 user's real name
 102 .It Location:
 103 user's normal location
 104 .It Home Phone:
 105 user's home phone
 106 .It Office Phone:
 107 user's office phone
 108 .El
 109 .Pp
 110 The
 111 .Ar login
 112 field is the user name used to access the computer account.
 113 .Pp
 114 The
 115 .Ar password
 116 field contains the encrypted form of the user's password.
 117 .Pp
 118 The
 119 .Ar uid
 120 field is the number associated with the
 121 .Ar login
 122 field.
 123 Both of these fields should be unique across the system (and often
 124 across a group of systems) as they control file access.
 125 .Pp
 126 While it is possible to have multiple entries with identical login names
 127 and/or identical user id's, it is usually a mistake to do so.  Routines
 128 that manipulate these files will often return only one of the multiple
 129 entries, and that one by random selection.
 130 .Pp
 131 The
 132 .Ar group
 133 field is the group that the user will be placed in at login.
 134 Since BSD supports multiple groups (see
 135 .Xr groups 1 )
 136 this field currently has little special meaning.
 137 This field may be filled in with either a number or a group name (see
 138 .Xr group 5 ) .
 139 .Pp
 140 The
 141 .Ar change
 142 field is the date by which the password must be changed.
 143 .Pp
 144 The
 145 .Ar expire
 146 field is the date on which the account expires.
 147 .Pp
 148 Both the
 149 .Ar change
 150 and
 151 .Ar expire
 152 fields should be entered in the form ``month day year'' where
 153 .Ar month
 154 is the month name (the first three characters are sufficient),
 155 .Ar day
 156 is the day of the month, and
 157 .Ar year
 158 is the year.
 159 .Pp
 160 The
 161 .Ar class
 162 field is currently unused.  In the near future it will be a key to
 163 a
 164 .Xr termcap 5
 165 style database of user attributes.
 166 .Pp
 167 The user's
 168 .Ar home directory
 169 is the full UNIX path name where the user
 170 will be placed at login.
 171 .Pp
 172 The
 173 .Ar shell
 174 field is the command interpreter the user prefers.
 175 If the
 176 .Ar shell
 177 field is empty, the Bourne shell,
 178 .Pa /bin/sh ,
 179 is assumed.
 180 When altering a login shell, and not the super-user, the user
 181 may not change from a non-standard shell or to a non-standard
 182 shell.
 183 Non-standard is defined as a shell not found in
 184 .Pa /etc/shells .
 185 .Pp
 186 The last four fields are for storing the user's
 187 .Ar full name , office location ,
 188 and
 189 .Ar home
 190 and
 191 .Ar work telephone
 192 numbers.
 193 .Pp
 194 Once the information has been verified,
 195 .Nm chpass
 196 uses
 197 .Xr pwd_mkdb 8
 198 to update the user database.
 199 .Sh ENVIRONMENT
 200 The
 201 .Xr vi 1
 202 editor will be used unless the environment variable EDITOR is set to
 203 an alternate editor.
 204 When the editor terminates, the information is re-read and used to
 205 update the user database itself.
 206 Only the user, or the super-user, may edit the information associated
 207 with the user.
 208 .Sh NIS INTERACTION
 209 .Nm Chpass
 210 can also be used in conjunction with NIS, however some restrictions
 211 apply.
 212 Currently,
 213 .Nm chpass
 214 can only make changes to the NIS passwd maps through
 215 .Xr yppasswdd 8 ,
 216 which only permits changes to a user's password, shell and gecos
 217 fields. It can not be used to change other user information or to
 218 add new records to the NIS passwd maps. (Doing that would require
 219 something such as ypupdated, which is not yet supported.)
 220 Furthermore,
 221 .Xr yppasswdd 8
 222 requires password authentication before it will make any
 223 changes, even if it receives a request from the super-user.
 224 .Pp
 225 As a result, the following restrictions apply when
 226 .Nm chpass
 227 is used with NIS:
 228 .Bl -enum -offset indent
 229 .It
 230 .Pa Only the shell and gecos information may be changed.
 231 All other
 232 fields are restricted, even when
 233 .Nm chpass
 234 is invoked by the super-user, because the
 235 .Xr yppasswdd 8
 236 daemon has no support for updating them. While support for
 237 changing other fields could be added, this would lead to
 238 compatibility problems with other NIS-capable systems.
 239 Even though the super-user may supply data for other fields
 240 while editing an entry, the extra information (other than the
 241 password -- see below) will be silently discarded.
 242 .It
 243 .Pa Password authentication is required.
 244 .Nm Chpass
 245 will prompt for the user's NIS password before effecting
 246 any changes. If the password is invalid, all changes will be
 247 discarded.
 248 .It
 249 .Pa Adding new records to the local
 250 .Pa password database is discouraged.
 251 .Nm Chpass
 252 will allow the administrator to add new records to the
 253 local password database while NIS is enabled, but this can lead to
 254 some confusion since the new records are appended to the end of
 255 the master password file, usually after the special NIS '+' entries.
 256 The administrator should use
 257 .Xr vipw 8
 258 to modify the local password
 259 file when NIS is running.
 260 .It
 261 .Pa Password changes are not permitted.
 262 Users should use
 263 .Xr passwd 1
 264 or
 265 .Xr yppasswd 1
 266 to change their NIS passwords. The super-user is allowed to specify
 267 a new password (even though the ``Password:'' field does not show
 268 up in the editor template, the super-user may add it back by hand),
 269 but even the super-user must supply the user's original password
 270 otherwise
 271 .Xr yppasswdd 8
 272 will refuse to update the NIS maps.
 273 .El
 274 .Pp
 275 There are also two extra option flags that are available when
 276 .Nm chpass
 277 is compiles with NIS support:
 278 .Bl -tag -width flag
 279 .It Fl l
 280 The
 281 .Fl l
 282 flag forces
 283 .Nm chpass
 284 to modify the local copy of a user's password
 285 information in the even that a user exists in both
 286 the local and NIS databases.
 287 .It Fl y
 288 This flag has the opposite effect of
 289 .Fl l .
 290 This flag is largely redundant since
 291 .Nm chpass
 292 operates on NIS entries by default if NIS is enabled.
 293 .El
 294 .Pp
 295 .Sh FILES
 296 .Bl -tag -width /etc/master.passwd -compact
 297 .It Pa /etc/master.passwd
 298 The user database
 299 .It Pa /etc/passwd
 300 A Version 7 format password file
 301 .It Pa /etc/chpass.XXXXXX
 302 Temporary copy of the password file
 303 .It Pa /etc/shells
 304 The list of approved shells
 305 .El
 306 .Sh SEE ALSO
 307 .Xr login 1 ,
 308 .Xr finger 1 ,
 309 .Xr passwd 1 ,
 310 .Xr getusershell 3 ,
 311 .Xr passwd 5 ,
 312 .Xr pwd_mkdb 8 ,
 313 .Xr vipw 8
 314 .Rs
 315 .%A Robert Morris
 316 and
 317 .%A Ken Thompson
 318 .%T "UNIX Password security"
 319 .Re
 320 .Sh NOTES
 321 The
 322 .Xr chfn 1 ,
 323 .Xr chsh 1 ,
 324 .Xr ypchpass 1 ,
 325 .Xr ypchfn 1
 326 and
 327 .Xr upchsh 1
 328 commands are really only links to
 329 .Nm chpass .
 330 .Sh BUGS
 331 User information should (and eventually will) be stored elsewhere.
 332 .Sh HISTORY
 333 The
 334 .Nm
 335 command appeared in
 336 .Bx 4.3 Reno .