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diff --git a/man/su.1.xml b/man/su.1.xml new file mode 100644 index 0000000..24143c3 --- /dev/null +++ b/man/su.1.xml @@ -0,0 +1,453 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!-- + Copyright (c) 1989 - 1990, Julianne Frances Haugh + Copyright (c) 2007 - 2008, Nicolas François + All rights reserved. + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions + are met: + 1. Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + 2. Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in the + documentation and/or other materials provided with the distribution. + 3. The name of the copyright holders or contributors may not be used to + endorse or promote products derived from this software without + specific prior written permission. + + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A + PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +--> +<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook V4.5//EN" + "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [ +<!ENTITY CONSOLE SYSTEM "login.defs.d/CONSOLE.xml"> +<!ENTITY CONSOLE_GROUPS SYSTEM "login.defs.d/CONSOLE_GROUPS.xml"> +<!ENTITY DEFAULT_HOME SYSTEM "login.defs.d/DEFAULT_HOME.xml"> +<!ENTITY ENV_HZ SYSTEM "login.defs.d/ENV_HZ.xml"> +<!ENTITY ENVIRON_FILE SYSTEM "login.defs.d/ENVIRON_FILE.xml"> +<!ENTITY ENV_PATH SYSTEM "login.defs.d/ENV_PATH.xml"> +<!ENTITY ENV_SUPATH SYSTEM "login.defs.d/ENV_SUPATH.xml"> +<!ENTITY ENV_TZ SYSTEM "login.defs.d/ENV_TZ.xml"> +<!ENTITY LOGIN_STRING SYSTEM "login.defs.d/LOGIN_STRING.xml"> +<!ENTITY MAIL_CHECK_ENAB SYSTEM "login.defs.d/MAIL_CHECK_ENAB.xml"> +<!ENTITY MAIL_DIR SYSTEM "login.defs.d/MAIL_DIR.xml"> +<!ENTITY QUOTAS_ENAB SYSTEM "login.defs.d/QUOTAS_ENAB.xml"> +<!ENTITY SULOG_FILE SYSTEM "login.defs.d/SULOG_FILE.xml"> +<!ENTITY SU_NAME SYSTEM "login.defs.d/SU_NAME.xml"> +<!ENTITY SU_WHEEL_ONLY SYSTEM "login.defs.d/SU_WHEEL_ONLY.xml"> +<!ENTITY SYSLOG_SU_ENAB SYSTEM "login.defs.d/SYSLOG_SU_ENAB.xml"> +<!ENTITY USERGROUPS_ENAB SYSTEM "login.defs.d/USERGROUPS_ENAB.xml"> +<!-- SHADOW-CONFIG-HERE --> +]> +<refentry id='su.1'> + <!-- $Id$ --> + <refentryinfo> + <author> + <firstname>Julianne Frances</firstname> + <surname>Haugh</surname> + <contrib>Creation, 1989</contrib> + </author> + <author> + <firstname>Thomas</firstname> + <surname>Kłoczko</surname> + <email>kloczek@pld.org.pl</email> + <contrib>shadow-utils maintainer, 2000 - 2007</contrib> + </author> + <author> + <firstname>Nicolas</firstname> + <surname>François</surname> + <email>nicolas.francois@centraliens.net</email> + <contrib>shadow-utils maintainer, 2007 - now</contrib> + </author> + </refentryinfo> + <refmeta> + <refentrytitle>su</refentrytitle> + <manvolnum>1</manvolnum> + <refmiscinfo class="sectdesc">User Commands</refmiscinfo> + <refmiscinfo class="source">shadow-utils</refmiscinfo> + <refmiscinfo class="version">&SHADOW_UTILS_VERSION;</refmiscinfo> + </refmeta> + <refnamediv id='name'> + <refname>su</refname> + <refpurpose>change user ID or become superuser</refpurpose> + </refnamediv> + <refsynopsisdiv id='synopsis'> + <cmdsynopsis> + <command>su</command> + <arg choice='opt'> + <replaceable>options</replaceable> + </arg> + <arg choice='opt'> + <arg choice='plain'> + <replaceable>username</replaceable> + </arg> + </arg> + </cmdsynopsis> + </refsynopsisdiv> + + <refsect1 id='description'> + <title>DESCRIPTION</title> + <para> + The <command>su</command> command is used to become another user during + a login session. Invoked without a <option>username</option>, + <command>su</command> defaults to + becoming the superuser. The optional argument <option>-</option> may + be used to provide an environment similar to what the user would + expect had the user logged in directly. + </para> + + <para> + Additional arguments may be provided after the username, in which case + they are supplied to the user's login shell. In particular, an + argument of <option>-c</option> will cause the next argument to be + treated as a command by most command interpreters. The command will be + executed by the shell specified in <filename>/etc/passwd</filename> + for the target user. + </para> + + <para> + You can use the <option>--</option> argument to separate + <command>su</command> options from the arguments supplied to the shell. + </para> + + <para>The user will be prompted for a password, if appropriate. Invalid + passwords will produce an error message. All attempts, both valid and + invalid, are logged to detect abuse of the system. + </para> + + <para> + The current environment is passed to the new shell. The value of + <envar>$PATH</envar> is reset to <filename>/bin:/usr/bin</filename> + for normal users, or <filename>/sbin:/bin:/usr/sbin:/usr/bin</filename> + for the superuser. This may be changed with the + <option>ENV_PATH</option> and <option>ENV_SUPATH</option> + definitions in <filename>/etc/login.defs</filename>. + </para> + + <para> + A subsystem login is indicated by the presence of a "*" as the first + character of the login shell. The given home directory will be used as + the root of a new file system which the user is actually logged into. + </para> + </refsect1> + + <refsect1 id='options'> + <title>OPTIONS</title> + <para>The options which apply to the <command>su</command> command are: + </para> + <variablelist remap='IP'> + <varlistentry> + <term> + <option>-c</option>, <option>--command</option> <replaceable>COMMAND</replaceable> + </term> + <listitem> + <para> + Specify a command that will be invoked by the shell using its + <option>-c</option>. + </para> + <para> + The executed command will have no controlling terminal. This + option cannot be used to execute interactive programs which + need a controlling TTY. + <!-- This avoids TTY hijacking when su is used to lower + privileges --> + </para> + </listitem> + </varlistentry> + <varlistentry> + <term> + <option>-</option>, <option>-l</option>, <option>--login</option> + </term> + <listitem> + <para> + Provide an environment similar to what the user would expect had + the user logged in directly. + </para> + <para> + When <option>-</option> is used, it must be specified before any + <option>username</option>. For portability it is recommended + to use it as last option, before any + <option>username</option>. The other forms + (<option>-l</option> and <option>--login</option>) + do not have this restriction. + </para> + </listitem> + </varlistentry> + <varlistentry> + <term> + <option>-s</option>, <option>--shell</option> <replaceable>SHELL</replaceable> + </term> + <listitem> + <para>The shell that will be invoked.</para> + <para> + The invoked shell is chosen from (highest priority first): + <!--This should be an ordered list, but lists inside another + list does not work well with current docbook. + - nekral - 2009.06.03 --> + <variablelist> + <varlistentry><term></term><listitem> + <para>The shell specified with --shell.</para> + </listitem></varlistentry> + <varlistentry><term></term><listitem> + <para> + If <option>--preserve-environment</option> is used, the + shell specified by the <envar>$SHELL</envar> environment + variable. + </para> + </listitem></varlistentry> + <varlistentry><term></term><listitem> + <para> + The shell indicated in the <filename>/etc/passwd</filename> + entry for the target user. + </para> + </listitem></varlistentry> + <varlistentry><term></term><listitem> + <para><filename>/bin/sh</filename> if a shell could not be + found by any above method.</para> + </listitem></varlistentry> + </variablelist> + </para> + <para> + If the target user has a restricted shell (i.e. the shell field of + this user's entry in <filename>/etc/passwd</filename> is not + listed in <filename>/etc/shells</filename>), then the + <option>--shell</option> option or the <envar>$SHELL</envar> + environment variable won't be taken into account, unless + <command>su</command> is called by root. + </para> + </listitem> + </varlistentry> + <varlistentry> + <term> + <option>-m</option>, <option>-p</option>, + <option>--preserve-environment</option> + </term> + <listitem> + <para> + Preserve the current environment, except for: + <variablelist> + <varlistentry> + <term><envar>$PATH</envar></term> + <listitem> + <para> + reset according to the + <filename>/etc/login.defs</filename> options + <option>ENV_PATH</option> or + <option>ENV_SUPATH</option> (see below); + </para> + </listitem> + </varlistentry> + <varlistentry> + <term><envar>$IFS</envar></term> + <listitem> + <para> + reset to + <quote><space><tab><newline></quote>, + if it was set. + </para> + </listitem> + </varlistentry> + </variablelist> + </para> + <para> + If the target user has a restricted shell, this option has no + effect (unless <command>su</command> is called by root). + </para> + <para> + Note that the default behavior for the environment is the + following: + <variablelist> + <varlistentry><term></term><listitem> + <para> + The <envar>$HOME</envar>, <envar>$SHELL</envar>, + <envar>$USER</envar>, <envar>$LOGNAME</envar>, + <envar>$PATH</envar>, and <envar>$IFS</envar> + environment variables are reset. + </para> + </listitem> + </varlistentry> + <varlistentry><term></term><listitem> + <para> + If <option>--login</option> is not used, the + environment is copied, except for the variables above. + </para> + </listitem> + </varlistentry> + <varlistentry><term></term><listitem> + <para> + If <option>--login</option> is used, the + <envar>$TERM</envar>, <envar>$COLORTERM</envar>, + <envar>$DISPLAY</envar>, and + <envar>$XAUTHORITY</envar> environment variables are + copied if they were set. + </para> + </listitem> + </varlistentry> + <varlistentry condition="no_pam"><term></term><listitem> + <para> + If <option>--login</option> is used, the + <envar>$TZ</envar>, <envar>$HZ</envar>, and + <envar>$MAIL</envar> environment + variables are set according to the + <filename>/etc/login.defs</filename> + options <option>ENV_TZ</option>, + <option>ENV_HZ</option>, <option>MAIL_DIR</option>, and + <option>MAIL_FILE</option> (see below). + </para> + </listitem> + </varlistentry> + <varlistentry condition="no_pam"><term></term><listitem> + <para> + If <option>--login</option> is used, other environment + variables might be set by the + <option>ENVIRON_FILE</option> file (see below). + </para> + </listitem> + </varlistentry> + <varlistentry condition="pam"><term></term><listitem> + <para> + Other environments might be set by PAM modules. + </para> + </listitem> + </varlistentry> + </variablelist> + </para> + </listitem> + </varlistentry> + </variablelist> + </refsect1> + + <refsect1 id='caveats'> + <title>CAVEATS</title> + <para> + This version of <command>su</command> has many compilation options, + only some of which may be in use at any particular site. + </para> + </refsect1> + + <refsect1 id='configuration'> + <title>CONFIGURATION</title> + <para> + The following configuration variables in + <filename>/etc/login.defs</filename> change the behavior of this + tool: + </para> + <variablelist> + &CONSOLE; + &CONSOLE_GROUPS; + &DEFAULT_HOME; + <phrase condition="no_pam">&ENV_HZ;</phrase> + &ENVIRON_FILE; + &ENV_PATH; + &ENV_SUPATH; + &ENV_TZ; + <phrase condition="no_pam">&LOGIN_STRING;</phrase> + &MAIL_CHECK_ENAB; + <phrase condition="no_pam">&MAIL_DIR;</phrase> + "AS_ENAB; + &SULOG_FILE; + &SU_NAME; + &SU_WHEEL_ONLY; + &SYSLOG_SU_ENAB; + <phrase condition="no_pam">&USERGROUPS_ENAB;</phrase> + </variablelist> + </refsect1> + + <refsect1 id='files'> + <title>FILES</title> + <variablelist> + <varlistentry> + <term><filename>/etc/passwd</filename></term> + <listitem> + <para>User account information.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><filename>/etc/shadow</filename></term> + <listitem> + <para>Secure user account information.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><filename>/etc/login.defs</filename></term> + <listitem> + <para>Shadow password suite configuration.</para> + </listitem> + </varlistentry> + </variablelist> + </refsect1> + + <refsect1 id='exit_values'> + <title>EXIT VALUES</title> + <para> + On success, <command>su</command> returns the exit value of the + command it executed. + </para> + <para> + If this command was terminated by a signal, <command>su</command> + returns the number of this signal plus 128. + </para> + <para> + If su has to kill the command (because it was asked to terminate, + and the command did not terminate in time), <command>su</command> + returns 255. + </para> + <para> + Some exit values from <command>su</command> are independent from the + executed command: + <variablelist> + <varlistentry> + <term><replaceable>0</replaceable></term> + <listitem> + <para>success (<option>--help</option> only)</para> + </listitem> + </varlistentry> + <varlistentry> + <term><replaceable>1</replaceable></term> + <listitem> + <para>System or authentication failure</para> + </listitem> + </varlistentry> + <varlistentry> + <term><replaceable>126</replaceable></term> + <listitem> + <para>The requested command was not found</para> + </listitem> + </varlistentry> + <varlistentry> + <term><replaceable>127</replaceable></term> + <listitem> + <para>The requested command could not be executed</para> + </listitem> + </varlistentry> + </variablelist> + </para> + </refsect1> + + <refsect1 id='see_also'> + <title>SEE ALSO</title> + <para><citerefentry> + <refentrytitle>login</refentrytitle><manvolnum>1</manvolnum> + </citerefentry>, + <citerefentry> + <refentrytitle>login.defs</refentrytitle><manvolnum>5</manvolnum> + </citerefentry>, + <citerefentry> + <refentrytitle>sg</refentrytitle><manvolnum>1</manvolnum> + </citerefentry>, + <citerefentry> + <refentrytitle>sh</refentrytitle><manvolnum>1</manvolnum> + </citerefentry>. + </para> + </refsect1> +</refentry> |