man/gpasswd.1.xml

   1 <?xml version="1.0" encoding="UTF-8"?>
   2 <!--
   3    Copyright (c) 1996       , Rafal Maszkowski
   4    Copyright (c) 2007 - 2008, Nicolas François
   5    All rights reserved.
   6
   7    Redistribution and use in source and binary forms, with or without
   8    modification, are permitted provided that the following conditions
   9    are met:
  10    1. Redistributions of source code must retain the above copyright
  11       notice, this list of conditions and the following disclaimer.
  12    2. Redistributions in binary form must reproduce the above copyright
  13       notice, this list of conditions and the following disclaimer in the
  14       documentation and/or other materials provided with the distribution.
  15    3. The name of the copyright holders or contributors may not be used to
  16       endorse or promote products derived from this software without
  17       specific prior written permission.
  18
  19    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  20    ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  21    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
  22    PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT
  23    HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  24    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  25    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  26    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  27    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  28    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  29    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  30 -->
  31 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook V4.5//EN"
  32   "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
  33 <!ENTITY ENCRYPT_METHOD        SYSTEM "login.defs.d/ENCRYPT_METHOD.xml">
  34 <!ENTITY MAX_MEMBERS_PER_GROUP SYSTEM "login.defs.d/MAX_MEMBERS_PER_GROUP.xml">
  35 <!ENTITY MD5_CRYPT_ENAB        SYSTEM "login.defs.d/MD5_CRYPT_ENAB.xml">
  36 <!ENTITY SHA_CRYPT_MIN_ROUNDS  SYSTEM "login.defs.d/SHA_CRYPT_MIN_ROUNDS.xml">
  37 ]>
  38
  39 <refentry id='gpasswd.1'>
  40   <!-- $Id: gpasswd.1.xml 3008 2009-05-26 19:23:40Z nekral-guest $ -->
  41   <refmeta>
  42     <refentrytitle>gpasswd</refentrytitle>
  43     <manvolnum>1</manvolnum>
  44     <refmiscinfo class="sectdesc">User Commands</refmiscinfo>
  45   </refmeta>
  46   <refnamediv id='name'>
  47     <refname>gpasswd</refname>
  48     <refpurpose>
  49       <phrase condition="no_gshadow">
  50         administer <filename>/etc/group</filename>
  51       </phrase>
  52       <phrase condition="gshadow">
  53         administer <filename>/etc/group</filename> and
  54         <filename>/etc/gshadow</filename>
  55       </phrase>
  56     </refpurpose>
  57   </refnamediv>
  58   <!-- body begins here -->
  59   <refsynopsisdiv id='synopsis'>
  60     <cmdsynopsis>
  61       <command>gpasswd</command>
  62       <arg choice='opt'>
  63         <replaceable>option</replaceable>
  64       </arg>
  65       <arg choice='plain'>
  66         <replaceable>group</replaceable>
  67       </arg>
  68     </cmdsynopsis>
  69   </refsynopsisdiv>
  70
  71   <refsect1 id='description'>
  72     <title>DESCRIPTION</title>
  73     <para>
  74       The <command>gpasswd</command> command is used to administer
  75       <filename>/etc/group</filename><phrase condition="gshadow">,
  76       and <filename>/etc/gshadow</filename></phrase>.
  77       Every group can have
  78       <phrase condition="gshadow">administrators,</phrase>
  79       members and a password.
  80     </para>
  81     <para condition="gshadow">
  82       System administrators can use the <option>-A</option> option to define
  83       group administrator(s) and the <option>-M</option> option to define
  84       members. They have all rights of group administrators and members.
  85     </para>
  86     <para>
  87       <command>gpasswd</command> called by
  88       <phrase condition="gshadow">a group administrator</phrase>
  89       <phrase condition="no_gshadow">a system administrator</phrase>
  90       with a group name only prompts for the new password of the
  91       <replaceable>group</replaceable>.
  92     </para>
  93     <para>
  94       If a password is set the members can still use <citerefentry>
  95       <refentrytitle>newgrp</refentrytitle><manvolnum>1</manvolnum>
  96       </citerefentry> without a password, and non-members must supply the
  97       password.
  98     </para>
  99
 100     <refsect2 id='notes_about_group_passwords'>
 101       <title>Notes about group passwords</title>
 102       <para>
 103         Group passwords are an inherent security problem since more than one
 104         person is permitted to know the password. However, groups are a
 105         useful tool for permitting co-operation between different users.
 106       </para>
 107     </refsect2>
 108
 109   </refsect1>
 110
 111   <refsect1 id='options'>
 112     <title>OPTIONS</title>
 113     <para condition="gshadow">
 114       Except for the <option>-A</option> and <option>-M</option> options,
 115       the options cannot be combined.
 116     </para>
 117     <para condition="no_gshadow">
 118       The options cannot be combined.
 119     </para>
 120     <para>
 121       The options which apply to the <command>gpasswd</command> command are:
 122     </para>
 123     <variablelist remap='IP'>
 124       <varlistentry>
 125         <term>
 126           <option>-a</option>, <option>--add</option> <replaceable>user</replaceable>
 127         </term>
 128         <listitem>
 129           <para>
 130             Add the <replaceable>user</replaceable> to the named
 131             <replaceable>group</replaceable>.
 132           </para>
 133         </listitem>
 134       </varlistentry>
 135     </variablelist>
 136     <variablelist remap='IP'>
 137       <varlistentry>
 138         <term>
 139           <option>-d</option>, <option>--delete</option> <replaceable>user</replaceable>
 140         </term>
 141         <listitem>
 142           <para>
 143             Remove the <replaceable>user</replaceable> from the named
 144             <replaceable>group</replaceable>.
 145           </para>
 146         </listitem>
 147       </varlistentry>
 148     </variablelist>
 149     <variablelist remap='IP'>
 150       <varlistentry>
 151         <term>
 152           <option>-r</option>, <option>--remove-password</option>
 153         </term>
 154         <listitem>
 155           <para>
 156             Remove the password from the named <replaceable>group</replaceable>.
 157             Only group members will be allowed to use
 158             <command>newgrp</command> to join the named
 159             <replaceable>group</replaceable>.
 160           </para>
 161         </listitem>
 162       </varlistentry>
 163     </variablelist>
 164     <variablelist remap='IP'>
 165       <varlistentry>
 166         <term>
 167           <option>-R</option>, <option>--restrict</option>
 168         </term>
 169         <listitem>
 170           <para>
 171             Restrict the access to the named <replaceable>group</replaceable>.
 172             Only group members will be allowed to use
 173             <command>newgrp</command> to join the named
 174             <replaceable>group</replaceable>.
 175           </para>
 176         </listitem>
 177       </varlistentry>
 178     </variablelist>
 179     <variablelist remap='IP' condition="gshadow">
 180       <varlistentry>
 181         <term>
 182           <option>-A</option>, <option>--administrators</option> <replaceable>user</replaceable>,...
 183         </term>
 184         <listitem>
 185           <para>
 186             Set the list of administrative users.
 187           </para>
 188         </listitem>
 189       </varlistentry>
 190     </variablelist>
 191     <variablelist remap='IP'>
 192       <varlistentry>
 193         <term>
 194           <option>-M</option>, <option>--members</option> <replaceable>user</replaceable>,...
 195         </term>
 196         <listitem>
 197           <para>
 198             Set the list of group members.
 199           </para>
 200         </listitem>
 201       </varlistentry>
 202     </variablelist>
 203   </refsect1>
 204
 205   <refsect1 id='caveats'>
 206     <title>CAVEATS</title>
 207     <para>
 208       This tool only operates on the <filename>/etc/group</filename>
 209       <phrase condition="gshadow"> and <filename>/etc/gshadow</filename>
 210       files.</phrase>
 211       <phrase condition="no_gshadow">file.</phrase>
 212       Thus you cannot change any NIS or LDAP group. This must be performed
 213       on the corresponding server.
 214     </para>
 215   </refsect1>
 216
 217   <refsect1 id='configuration'>
 218     <title>CONFIGURATION</title>
 219     <para>
 220       The following configuration variables in
 221       <filename>/etc/login.defs</filename> change the behavior of this
 222       tool:
 223     </para>
 224     <variablelist>
 225       &ENCRYPT_METHOD;
 226       &MAX_MEMBERS_PER_GROUP;
 227       &MD5_CRYPT_ENAB;
 228       &SHA_CRYPT_MIN_ROUNDS; <!--This also document SHA_CRYPT_MAX_ROUNDS-->
 229     </variablelist>
 230   </refsect1>
 231
 232   <refsect1 id='files'>
 233     <title>FILES</title>
 234     <variablelist>
 235       <varlistentry>
 236         <term><filename>/etc/group</filename></term>
 237         <listitem>
 238           <para>Group account information.</para>
 239         </listitem>
 240       </varlistentry>
 241       <varlistentry condition="gshadow">
 242         <term><filename>/etc/gshadow</filename></term>
 243         <listitem>
 244           <para>Secure group account information.</para>
 245         </listitem>
 246       </varlistentry>
 247     </variablelist>
 248   </refsect1>
 249
 250   <refsect1 id='see_also'>
 251     <title>SEE ALSO</title>
 252     <para>
 253       <citerefentry>
 254         <refentrytitle>newgrp</refentrytitle><manvolnum>1</manvolnum>
 255       </citerefentry>,
 256       <citerefentry>
 257         <refentrytitle>groupadd</refentrytitle><manvolnum>8</manvolnum>
 258       </citerefentry>,
 259       <citerefentry>
 260         <refentrytitle>groupdel</refentrytitle><manvolnum>8</manvolnum>
 261       </citerefentry>,
 262       <citerefentry>
 263         <refentrytitle>groupmod</refentrytitle><manvolnum>8</manvolnum>
 264       </citerefentry>,
 265       <citerefentry>
 266         <refentrytitle>grpck</refentrytitle><manvolnum>8</manvolnum>
 267       </citerefentry>,
 268       <citerefentry>
 269         <refentrytitle>group</refentrytitle><manvolnum>5</manvolnum>
 270       </citerefentry><phrase condition="gshadow">,
 271       <citerefentry>
 272         <refentrytitle>gshadow</refentrytitle><manvolnum>5</manvolnum>
 273       </citerefentry></phrase>.
 274     </para>
 275   </refsect1>
 276 </refentry>