man/sd_bus_creds_new_from_pid.xml

   1 <?xml version='1.0'?> <!--*- Mode: nxml; nxml-child-indent: 2; indent-tabs-mode: nil -*-->
   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
   3 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
   4
   5 <!--
   6 This file is part of systemd.
   7
   8 Copyright 2014 Zbigniew Jędrzejewski-Szmek
   9
  10 systemd is free software; you can redistribute it and/or modify it
  11 under the terms of the GNU Lesser General Public License as published by
  12 the Free Software Foundation; either version 2.1 of the License, or
  13 (at your option) any later version.
  14
  15 systemd is distributed in the hope that it will be useful, but
  16 WITHOUT ANY WARRANTY; without even the implied warranty of
  17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  18 Lesser General Public License for more details.
  19
  20 You should have received a copy of the GNU Lesser General Public License
  21 along with systemd; If not, see <http://www.gnu.org/licenses/>.
  22 -->
  23
  24 <refentry id="sd_bus_creds_new_from_pid" conditional="ENABLE_KDBUS">
  25
  26   <refentryinfo>
  27     <title>sd_bus_creds_new_from_pid</title>
  28     <productname>systemd</productname>
  29
  30     <authorgroup>
  31       <author>
  32         <contrib>A monkey with a typewriter</contrib>
  33         <firstname>Zbigniew</firstname>
  34         <surname>Jędrzejewski-Szmek</surname>
  35         <email>zbyszek@in.waw.pl</email>
  36       </author>
  37     </authorgroup>
  38   </refentryinfo>
  39
  40   <refmeta>
  41     <refentrytitle>sd_bus_creds_new_from_pid</refentrytitle>
  42     <manvolnum>3</manvolnum>
  43   </refmeta>
  44
  45   <refnamediv>
  46     <refname>sd_bus_creds_new_from_pid</refname>
  47     <refname>sd_bus_creds_get_mask</refname>
  48     <refname>sd_bus_creds_ref</refname>
  49     <refname>sd_bus_creds_unref</refname>
  50
  51     <refpurpose>Retrieve credentials object for the specified PID</refpurpose>
  52   </refnamediv>
  53
  54   <refsynopsisdiv>
  55     <funcsynopsis>
  56       <funcsynopsisinfo>#include &lt;systemd/sd-bus.h&gt;</funcsynopsisinfo>
  57
  58       <funcprototype>
  59         <funcdef>int <function>sd_bus_creds_new_from_pid</function></funcdef>
  60         <paramdef>pid_t <parameter>pid</parameter></paramdef>
  61         <paramdef>uint64_t <parameter>creds_mask</parameter></paramdef>
  62         <paramdef>sd_bus_creds **<parameter>ret</parameter></paramdef>
  63       </funcprototype>
  64
  65       <funcprototype>
  66         <funcdef>uint64_t <function>sd_bus_creds_get_mask</function></funcdef>
  67         <paramdef>const sd_bus_creds *<parameter>c</parameter></paramdef>
  68       </funcprototype>
  69
  70       <funcprototype>
  71         <funcdef>sd_bus_creds *<function>sd_bus_creds_ref</function></funcdef>
  72         <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef>
  73       </funcprototype>
  74
  75       <funcprototype>
  76         <funcdef>sd_bus_creds *<function>sd_bus_creds_unref</function></funcdef>
  77         <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef>
  78       </funcprototype>
  79     </funcsynopsis>
  80
  81     <para>
  82       <constant>SD_BUS_CREDS_PID</constant>,
  83       <constant>SD_BUS_CREDS_TID</constant>,
  84       <constant>SD_BUS_CREDS_UID</constant>,
  85       <constant>SD_BUS_CREDS_GID</constant>,
  86       <constant>SD_BUS_CREDS_COMM</constant>,
  87       <constant>SD_BUS_CREDS_TID_COMM</constant>,
  88       <constant>SD_BUS_CREDS_EXE</constant>,
  89       <constant>SD_BUS_CREDS_CMDLINE</constant>,
  90       <constant>SD_BUS_CREDS_CGROUP</constant>,
  91       <constant>SD_BUS_CREDS_UNIT</constant>,
  92       <constant>SD_BUS_CREDS_USER_UNIT</constant>,
  93       <constant>SD_BUS_CREDS_SLICE</constant>,
  94       <constant>SD_BUS_CREDS_SESSION</constant>,
  95       <constant>SD_BUS_CREDS_OWNER_UID</constant>,
  96       <constant>SD_BUS_CREDS_EFFECTIVE_CAPS</constant>,
  97       <constant>SD_BUS_CREDS_PERMITTED_CAPS</constant>,
  98       <constant>SD_BUS_CREDS_INHERITABLE_CAPS</constant>,
  99       <constant>SD_BUS_CREDS_BOUNDING_CAPS</constant>,
 100       <constant>SD_BUS_CREDS_SELINUX_CONTEXT</constant>,
 101       <constant>SD_BUS_CREDS_AUDIT_SESSION_ID</constant>,
 102       <constant>SD_BUS_CREDS_AUDIT_LOGIN_UID</constant>,
 103       <constant>SD_BUS_CREDS_UNIQUE_NAME</constant>,
 104       <constant>SD_BUS_CREDS_WELL_KNOWN_NAMES</constant>,
 105       <constant>_SD_BUS_CREDS_ALL</constant>
 106     </para>
 107   </refsynopsisdiv>
 108
 109   <refsect1>
 110     <title>Description</title>
 111
 112     <para><function>sd_bus_creds_new_from_pid()</function> creates a new
 113     credentials object and fills it with information about the process
 114     <parameter>pid</parameter>. This pointer to this object will
 115     be stored in <parameter>ret</parameter> pointer.</para>
 116
 117     <para>The information that will be stored is determined by
 118     <parameter>creds_mask</parameter>. It may contain a subset of ORed
 119     constants <constant>SD_BUS_CREDS_PID</constant>,
 120     <constant>SD_BUS_CREDS_TID</constant>,
 121     <constant>SD_BUS_CREDS_UID</constant>,
 122     <constant>SD_BUS_CREDS_GID</constant>,
 123     <constant>SD_BUS_CREDS_COMM</constant>,
 124     <constant>SD_BUS_CREDS_TID_COMM</constant>,
 125     <constant>SD_BUS_CREDS_EXE</constant>,
 126     <constant>SD_BUS_CREDS_CMDLINE</constant>,
 127     <constant>SD_BUS_CREDS_CGROUP</constant>,
 128     <constant>SD_BUS_CREDS_UNIT</constant>,
 129     <constant>SD_BUS_CREDS_USER_UNIT</constant>,
 130     <constant>SD_BUS_CREDS_SLICE</constant>,
 131     <constant>SD_BUS_CREDS_SESSION</constant>,
 132     <constant>SD_BUS_CREDS_OWNER_UID</constant>,
 133     <constant>SD_BUS_CREDS_EFFECTIVE_CAPS</constant>,
 134     <constant>SD_BUS_CREDS_PERMITTED_CAPS</constant>,
 135     <constant>SD_BUS_CREDS_INHERITABLE_CAPS</constant>,
 136     <constant>SD_BUS_CREDS_BOUNDING_CAPS</constant>,
 137     <constant>SD_BUS_CREDS_SELINUX_CONTEXT</constant>,
 138     <constant>SD_BUS_CREDS_AUDIT_SESSION_ID</constant>,
 139     <constant>SD_BUS_CREDS_AUDIT_LOGIN_UID</constant>,
 140     <constant>SD_BUS_CREDS_UNIQUE_NAME</constant>,
 141     <constant>SD_BUS_CREDS_WELL_KNOWN_NAMES</constant>,
 142     or <constant>_SD_BUS_CREDS_ALL</constant> to indicate
 143     all known fields.</para>
 144
 145     <para>Fields can be retrieved from the credentials object using
 146     <citerefentry><refentrytitle>sd_bus_creds_get_pid</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 147     and other functions which correspond directly to the constants
 148     listed above.</para>
 149
 150     <para>A mask of fields which were actually successfully set
 151     (acquired from <filename>/proc</filename>, etc.) can be retrieved
 152     with <function>sd_bus_creds_get_mask()</function>. If the
 153     credentials object was created with
 154     <function>sd_bus_creds_new_from_pid()</function>, this will be a
 155     subset of fields requested in <parameter>creds_mask</parameter>.
 156     </para>
 157
 158     <para><function>sd_bus_creds_ref</function> creates a new
 159     reference to the credentials object <parameter>c</parameter>. This
 160     object will not be destroyed until
 161     <function>sd_bus_creds_unref</function> has been called as many
 162     times plus once more. Once the reference count has dropped to zero,
 163     <parameter>c</parameter> cannot be used anymore, so further
 164     calls to <function>sd_bus_creds_ref(c)</function> or
 165     <function>sd_bus_creds_unref(c)</function> are illegal.</para>
 166
 167     <para><function>sd_bus_creds_unref</function> destroys a reference
 168     to <parameter>c</parameter>.</para>
 169   </refsect1>
 170
 171   <refsect1>
 172     <title>Return Value</title>
 173
 174     <para>On success, <function>sd_bus_creds_new_from_pid()</function>
 175     returns 0 or a positive integer. On failure, it returns a negative
 176     errno-style error code.</para>
 177
 178     <para><function>sd_bus_creds_get_mask()</function> returns the
 179     mask of successfully acquired fields.</para>
 180
 181     <para><function>sd_bus_creds_ref</function> always returns the
 182     argument.</para>
 183
 184     <para><function>sd_bus_creds_unref</function> always returns
 185     <constant>NULL</constant>.</para>
 186   </refsect1>
 187
 188   <refsect1>
 189     <title>Reference ownership</title>
 190
 191     <para>Function <function>sd_bus_creds_new_from_pid()</function>
 192     creates a new object and the caller owns the sole reference. When
 193     not needed anymore, this reference should be destroyed with
 194     <citerefentry><refentrytitle>sd_bus_creds_unref</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
 195     </para>
 196   </refsect1>
 197
 198   <refsect1>
 199     <title>Errors</title>
 200
 201     <para>Returned errors may indicate the following problems:</para>
 202
 203     <variablelist>
 204
 205       <varlistentry>
 206         <term><constant>-ESRCH</constant></term>
 207
 208         <listitem><para>Specified <parameter>pid</parameter> could not
 209         be found.</para></listitem>
 210       </varlistentry>
 211
 212       <varlistentry>
 213         <term><constant>-EINVAL</constant></term>
 214
 215         <listitem><para>Specified parameter is invalid
 216         (<constant>NULL</constant> in case of output
 217         parameters).</para></listitem>
 218       </varlistentry>
 219
 220       <varlistentry>
 221         <term><constant>-ENOMEM</constant></term>
 222
 223         <listitem><para>Memory allocation failed.</para></listitem>
 224       </varlistentry>
 225     </variablelist>
 226   </refsect1>
 227
 228   <refsect1>
 229     <title>Notes</title>
 230
 231     <para><function>sd_bus_creds_new_from_pid()</function> is
 232     available as a shared library, which can be compiled and linked to
 233     with the
 234     <constant>libsystemd</constant> <citerefentry project='die-net'><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 235     file.</para>
 236   </refsect1>
 237
 238   <refsect1>
 239     <title>See Also</title>
 240
 241     <para>
 242       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 243       <citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 244       <citerefentry><refentrytitle>sd_bus_creds_ref</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 245       <citerefentry><refentrytitle>sd_bus_creds_unref</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 246       <citerefentry><refentrytitle>sd_bus_creds_get_pid</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 247       <citerefentry><refentrytitle>sd_bus_creds_get_tid</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 248       <citerefentry><refentrytitle>sd_bus_creds_get_uid</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 249       <citerefentry><refentrytitle>sd_bus_creds_get_gid</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 250       <citerefentry><refentrytitle>sd_bus_creds_get_comm</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 251       <citerefentry><refentrytitle>sd_bus_creds_get_tid_comm</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 252       <citerefentry><refentrytitle>sd_bus_creds_get_exe</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 253       <citerefentry><refentrytitle>sd_bus_creds_get_cmdline</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 254       <citerefentry><refentrytitle>sd_bus_creds_get_cgroup</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 255       <citerefentry><refentrytitle>sd_bus_creds_get_unit</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 256       <citerefentry><refentrytitle>sd_bus_creds_get_user_unit</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 257       <citerefentry><refentrytitle>sd_bus_creds_get_slice</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 258       <citerefentry><refentrytitle>sd_bus_creds_get_session</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 259       <citerefentry><refentrytitle>sd_bus_creds_get_owner_uid</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 260       <citerefentry><refentrytitle>sd_bus_creds_has_effective_cap</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 261       <citerefentry><refentrytitle>sd_bus_creds_has_permitted_cap</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 262       <citerefentry><refentrytitle>sd_bus_creds_has_inheritable_cap</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 263       <citerefentry><refentrytitle>sd_bus_creds_has_bounding_cap</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 264       <citerefentry><refentrytitle>sd_bus_creds_get_selinux_context</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 265       <citerefentry><refentrytitle>sd_bus_creds_get_audit_session_id</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 266       <citerefentry><refentrytitle>sd_bus_creds_get_audit_login_uid</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 267       <citerefentry><refentrytitle>sd_bus_creds_get_unique_name</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 268       <citerefentry><refentrytitle>sd_bus_creds_get_well_known_names</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 269     </para>
 270   </refsect1>
 271
 272 </refentry>