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   1 <?xml version="1.0" encoding="UTF-8"?>
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  30 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook V4.5//EN"
  31   "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
  32 <!-- SHADOW-CONFIG-HERE -->
  33 ]>
  34
  35 <refentry id='newuidmap.1'>
  36   <refmeta>
  37     <refentrytitle>newuidmap</refentrytitle>
  38     <manvolnum>1</manvolnum>
  39     <refmiscinfo class="sectdesc">User Commands</refmiscinfo>
  40     <refmiscinfo class="source">shadow-utils</refmiscinfo>
  41     <refmiscinfo class="version">&SHADOW_UTILS_VERSION;</refmiscinfo>
  42   </refmeta>
  43   <refnamediv id='name'>
  44     <refname>newuidmap</refname>
  45     <refpurpose>set the uid mapping of a user namespace</refpurpose>
  46   </refnamediv>
  47
  48   <refsynopsisdiv id='synopsis'>
  49     <cmdsynopsis>
  50       <command>newuidmap</command>
  51       <arg choice='plain'>
  52         <replaceable>pid</replaceable>
  53       </arg>
  54       <arg choice='plain'>
  55         <replaceable>uid</replaceable>
  56       </arg>
  57       <arg choice='plain'>
  58         <replaceable>loweruid</replaceable>
  59       </arg>
  60       <arg choice='plain'>
  61         <replaceable>count</replaceable>
  62       </arg>
  63       <arg choice='opt'>
  64         <arg choice='plain'>
  65           <replaceable>uid</replaceable>
  66         </arg>
  67         <arg choice='plain'>
  68           <replaceable>loweruid</replaceable>
  69         </arg>
  70         <arg choice='plain'>
  71           <replaceable>count</replaceable>
  72         </arg>
  73         <arg choice='opt'>
  74           <replaceable>...</replaceable>
  75         </arg>
  76       </arg>
  77     </cmdsynopsis>
  78   </refsynopsisdiv>
  79
  80   <refsect1 id='description'>
  81     <title>DESCRIPTION</title>
  82     <para>
  83       The <command>newuidmap</command> sets <filename>/proc/[pid]/uid_map</filename> based on its
  84       command line arguments and the uids allowed in <filename>/etc/subuid</filename>.
  85       Note that the root user is not exempted from the requirement for a valid
  86       <filename>/etc/subuid</filename> entry.
  87     </para>
  88
  89     <para>
  90       After the pid argument, <command>newuidmap</command> expects sets of 3 integers:
  91       <variablelist>
  92         <varlistentry>
  93           <term>uid</term>
  94           <listitem>
  95             <para>
  96               Beginning of the range of UIDs inside the user namespace.
  97             </para>
  98           </listitem>
  99         </varlistentry>
 100         <varlistentry>
 101           <term>loweruid</term>
 102           <listitem>
 103             <para>
 104               Beginning of the range of UIDs outside the user namespace.
 105             </para>
 106           </listitem>
 107         </varlistentry>
 108         <varlistentry>
 109           <term>count</term>
 110           <listitem>
 111             <para>
 112               Length of the ranges (both inside and outside the user namespace).
 113             </para>
 114           </listitem>
 115         </varlistentry>
 116       </variablelist>
 117     </para>
 118
 119     <para>
 120       <command>newuidmap</command> verifies that the caller is the owner
 121       of the process indicated by <option>pid</option> and that for each
 122       of the above sets, each of the UIDs in the range [loweruid,
 123       loweruid+count] is allowed to the caller according to
 124       <filename>/etc/subuid</filename> before setting
 125       <filename>/proc/[pid]/uid_map</filename>.
 126     </para>
 127     <para>
 128       Note that newuidmap may be used only once for a given process.
 129     </para>
 130   </refsect1>
 131
 132   <refsect1 id='options'>
 133     <title>OPTIONS</title>
 134     <para>
 135       There currently are no options to the <command>newuidmap</command> command.
 136     </para>
 137     <variablelist remap='IP'>
 138     </variablelist>
 139   </refsect1>
 140
 141   <refsect1 id='files'>
 142     <title>FILES</title>
 143     <variablelist>
 144       <varlistentry>
 145         <term><filename>/etc/subuid</filename></term>
 146         <listitem>
 147           <para>List of user's subordinate user IDs.</para>
 148         </listitem>
 149       </varlistentry>
 150       <varlistentry>
 151         <term><filename>/proc/[pid]/uid_map</filename></term>
 152         <listitem>
 153           <para>Mapping of uids from one between user namespaces.</para>
 154         </listitem>
 155       </varlistentry>
 156     </variablelist>
 157   </refsect1>
 158
 159   <refsect1 id='see_also'>
 160     <title>SEE ALSO</title>
 161     <para>
 162       <citerefentry>
 163         <refentrytitle>login.defs</refentrytitle><manvolnum>5</manvolnum>
 164       </citerefentry>,
 165       <citerefentry>
 166         <refentrytitle>newusers</refentrytitle><manvolnum>8</manvolnum>
 167       </citerefentry>,
 168       <citerefentry>
 169         <refentrytitle>subuid</refentrytitle><manvolnum>5</manvolnum>
 170       </citerefentry>,
 171       <citerefentry>
 172         <refentrytitle>useradd</refentrytitle><manvolnum>8</manvolnum>
 173       </citerefentry>,
 174       <citerefentry>
 175         <refentrytitle>usermod</refentrytitle><manvolnum>8</manvolnum>
 176       </citerefentry>,
 177       <citerefentry>
 178         <refentrytitle>userdel</refentrytitle><manvolnum>8</manvolnum>
 179       </citerefentry>.
 180     </para>
 181   </refsect1>
 182 </refentry>