<?xml version='1.0'?> <!--*-nxml-*--> <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> <!-- This file is part of systemd. Copyright 2014 Zbigniew Jędrzejewski-Szmek systemd is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. systemd is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with systemd; If not, see <http://www.gnu.org/licenses/>. --> <refentry id="sd_bus_creds_get_pid" conditional="ENABLE_KDBUS"> <refentryinfo> <title>sd_bus_creds_get_pid</title> <productname>systemd</productname> <authorgroup> <author> <contrib>A monkey with a typewriter</contrib> <firstname>Zbigniew</firstname> <surname>Jędrzejewski-Szmek</surname> <email>zbyszek@in.waw.pl</email> </author> </authorgroup> </refentryinfo> <refmeta> <refentrytitle>sd_bus_creds_get_pid</refentrytitle> <manvolnum>3</manvolnum> </refmeta> <refnamediv> <refname>sd_bus_creds_get_pid</refname> <refname>sd_bus_creds_get_pid_starttime</refname> <refname>sd_bus_creds_get_tid</refname> <refname>sd_bus_creds_get_uid</refname> <refname>sd_bus_creds_get_gid</refname> <refname>sd_bus_creds_get_comm</refname> <refname>sd_bus_creds_get_tid_comm</refname> <refname>sd_bus_creds_get_exe</refname> <refname>sd_bus_creds_get_cmdline</refname> <refname>sd_bus_creds_get_cgroup</refname> <refname>sd_bus_creds_get_unit</refname> <refname>sd_bus_creds_get_user_unit</refname> <refname>sd_bus_creds_get_slice</refname> <refname>sd_bus_creds_get_session</refname> <refname>sd_bus_creds_get_owner_uid</refname> <refname>sd_bus_creds_has_effective_cap</refname> <refname>sd_bus_creds_has_permitted_cap</refname> <refname>sd_bus_creds_has_inheritable_cap</refname> <refname>sd_bus_creds_has_bounding_cap</refname> <refname>sd_bus_creds_get_selinux_context</refname> <refname>sd_bus_creds_get_audit_session_id</refname> <refname>sd_bus_creds_get_audit_login_uid</refname> <refname>sd_bus_creds_get_unique_name</refname> <refname>sd_bus_creds_get_well_known_names</refname> <refpurpose>Retrieve fields from a credentials object</refpurpose> </refnamediv> <refsynopsisdiv> <funcsynopsis> <funcsynopsisinfo>#include <systemd/sd-bus.h></funcsynopsisinfo> <funcprototype> <funcdef>int <function>sd_bus_creds_get_pid</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>pid_t *<parameter>pid</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_get_pid_starttime</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>uint64_t *<parameter>usec</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_get_tid</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>pid_t *<parameter>tid</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_get_pid</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>uid_t *<parameter>uid</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_get_gid</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>gid_t *<parameter>gid</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_get_comm</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>const char **<parameter>comm</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_get_tid_comm</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>const char **<parameter>comm</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_get_exe</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>const char **<parameter>exe</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_get_cmdline</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>char ***<parameter>cmdline</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_get_cgroup</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>const char **<parameter>cgroup</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_get_unit</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>const char **<parameter>unit</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_get_user_unit</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>const char **<parameter>unit</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_get_slice</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>const char **<parameter>slice</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_get_session</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>const char **<parameter>slice</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_get_owner_uid</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>uid_t *<parameter>uid</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_has_effective_cap</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>int <parameter>capability</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_has_permitted_cap</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>int <parameter>capability</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_has_inheritable_cap</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>int <parameter>capability</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_has_bounding_cap</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>int <parameter>capability</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_get_selinux_context</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>const char **<parameter>context</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_get_audit_session_id</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>uint32_t *<parameter>sessionid</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_get_audit_login_uid</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>uid_t *<parameter>loginuid</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_get_unique_name</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>const char **<parameter>name</parameter></paramdef> </funcprototype> <funcprototype> <funcdef>int <function>sd_bus_creds_get_well_known_names</function></funcdef> <paramdef>sd_bus_creds *<parameter>c</parameter></paramdef> <paramdef>char ***<parameter>name</parameter></paramdef> </funcprototype> </funcsynopsis> </refsynopsisdiv> <refsect1> <title>Description</title> <para>These functions return information from an <parameter>sd_bus_creds</parameter> object. It may be created with <citerefentry><refentrytitle>sd_bus_creds_new_from_pid</refentrytitle><manvolnum>3</manvolnum></citerefentry>, in which case it will describe the specified process, or it may be created by <citerefentry><refentrytitle>sd_bus_get_peer_creds</refentrytitle><manvolnum>3</manvolnum></citerefentry>, in which case it will describe the process at the other endpoint of a connection. </para> <para><function>sd_bus_creds_get_pid</function> will retrieve the PID (process identifier).</para> <para><function>sd_bus_creds_get_pid_starttime</function> will retrieve the time since the start of the epoch in microseconds since the process was started.</para> <para><function>sd_bus_creds_get_tid</function> will retrieve the TID (thread identifier).</para> <para><function>sd_bus_creds_get_uid</function> will retrieve the numeric UID (user identifier).</para> <para><function>sd_bus_creds_get_gid</function> will retrieve the numeric GID (group identifier).</para> <para><function>sd_bus_creds_get_comm</function> will retrieve the comm field (truncated name of the executable, as stored in <filename>/proc/<replaceable>pid</replaceable>/comm</filename>). </para> <para><function>sd_bus_creds_get_tid_comm</function> will retrieve the comm field of the thread (as stored in <filename>/proc/<replaceable>pid</replaceable>/task/<replaceable>tid</replaceable>/comm</filename>). </para> <para><function>sd_bus_creds_get_exe</function> will retrieve the path to the program (as stored in the <filename>/proc/<replaceable>pid</replaceable>/exe</filename> link, but with <literal> (deleted)</literal> suffix removed). </para> <para><function>sd_bus_creds_get_cmdline</function> will retrieve an array of command-line arguments (as stored in <filename>/proc/<replaceable>pid</replaceable>/cmdline</filename>). </para> <para><function>sd_bus_creds_get_cgroup</function> will retrieve the cgroup path. See <ulink url="https://www.kernel.org/doc/Documentation/cgroups/cgroups.txt">cgroups.txt</ulink>. </para> <para><function>sd_bus_creds_get_unit</function> will retrieve the systemd unit name (in the system instance of systemd) that the process is part of. See <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. </para> <para><function>sd_bus_creds_get_user_unit</function> will retrieve the systemd unit name (in the user instance of systemd) that the process is part of. See <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. </para> <para><function>sd_bus_creds_get_slice</function> will retrieve the systemd slice (a unit in the system instance of systemd) that the process is part of. See <citerefentry><refentrytitle>systemd.slice</refentrytitle><manvolnum>5</manvolnum></citerefentry>. </para> <para><function>sd_bus_creds_get_session</function> will retrieve the logind session that the process is part of. See <citerefentry><refentrytitle>systemd-logind.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>. </para> <para><function>sd_bus_creds_get_owner_uid</function> will retrieve the numeric UID (user identifier) of the user who owns the slice that the process is part of. See <citerefentry><refentrytitle>systemd.slice</refentrytitle><manvolnum>5</manvolnum></citerefentry> <!-- and <citerefentry><refentrytitle>systemd-user-sessions.service</refentrytitle><manvolnum>8</manvolnum></citerefentry> -->. </para> <para><function>sd_bus_creds_has_effective_cap</function> will check whether the capability specified by <parameter>capability</parameter> was set in the effective capabilities mask. A positive return value means that is was set, zero means that it was not set, and a negative return value signifies an error. See <citerefentry project='man-pages'><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry> and <varname>Capabilities=</varname> and <varname>CapabilityBoundingSet=</varname> settings in <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>. </para> <para><function>sd_bus_creds_has_permitted_cap</function> is similar to <function>sd_bus_creds_has_effective_cap</function>, but will check the permitted capabilities mask.</para> <para><function>sd_bus_creds_has_inheritable_cap</function> is similar to <function>sd_bus_creds_has_effective_cap</function>, but will check the inheritable capabilities mask.</para> <para><function>sd_bus_creds_has_bounding_cap</function> is similar to <function>sd_bus_creds_has_effective_cap</function>, but will check the bounding capabilities mask.</para> <para><function>sd_bus_creds_get_selinux_context</function> will retrieve the SELinux security context (label) of the process.</para> <para><function>sd_bus_creds_get_audit_session_id</function> will retrieve the audit session identifier of the process.</para> <para><function>sd_bus_creds_get_audit_login_uid</function> will retrieve the audit user login identifier (the identifier of the user who is "responsible" for the session).</para> <para><function>sd_bus_creds_get_unique_name</function> will retrieve the D-Bus unique name. See <ulink url="http://dbus.freedesktop.org/doc/dbus-specification.html#message-protocol-names-bus">The D-Bus specification</ulink>.</para> <para><function>sd_bus_creds_get_well_known_names</function> will retrieve the set of D-Bus well-known names. See <ulink url="http://dbus.freedesktop.org/doc/dbus-specification.html#message-protocol-names-bus">The D-Bus specification</ulink>.</para> <para>All functions that take a <parameter>const char**</parameter> parameter will store the answer there as an address of a NUL-terminated string. It will be valid as long as <parameter>c</parameter> remains valid, and should not be freed or modified by the caller.</para> <para>All functions that take a <parameter>char***</parameter> parameter will store the answer there as an address of a an array of strings. Each invidividual string is NUL-terminated, and the array is NULL-terminated as a whole. It will be valid as long as <parameter>c</parameter> remains valid, and should not be freed or modified by the caller.</para> </refsect1> <refsect1> <title>Return Value</title> <para>On success, these calls return 0 or a positive integer. On failure, these calls return a negative errno-style error code. </para> </refsect1> <refsect1> <title>Errors</title> <para>Returned errors may indicate the following problems:</para> <variablelist> <varlistentry> <term><varname>-ENODATA</varname></term> <listitem><para>Given field is not available in <parameter>c</parameter>.</para> </listitem> </varlistentry> <varlistentry> <term><varname>-ENOENT</varname></term> <listitem><para>Given field is not specified for the sender. This will be returned by <function>sd_bus_get_unit</function>, <function>sd_bus_get_user_unit</function>, <function>sd_bus_get_slice</function>, <function>sd_bus_get_session</function>, and <function>sd_bus_get_owner_uid</function> if the sender is not part of a systemd system unit, systemd user unit, systemd slice, logind session, or a systemd user session.</para> </listitem> </varlistentry> <varlistentry> <term><varname>-ENXIO</varname></term> <listitem><para>An error occured in parsing cgroup paths. <filename>libsystemd</filename> might be out of sync with the running systemd version.</para></listitem> </varlistentry> <varlistentry> <term><varname>-EINVAL</varname></term> <listitem><para>Specified pointer parameter is <constant>NULL</constant>. </para></listitem> </varlistentry> <varlistentry> <term><varname>-ENOMEM</varname></term> <listitem><para>Memory allocation failed.</para></listitem> </varlistentry> </variablelist> </refsect1> <refsect1> <title>Notes</title> <para><function>sd_bus_open_user()</function> and other functions described here are available as a shared library, which can be compiled and linked to with the <constant>libsystemd</constant> <citerefentry project='die-net'><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry> file.</para> </refsect1> <refsect1> <title>See Also</title> <para> <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, <citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry>, <citerefentry><refentrytitle>fork</refentrytitle><manvolnum>2</manvolnum></citerefentry>, <citerefentry><refentrytitle>execve</refentrytitle><manvolnum>2</manvolnum></citerefentry>, <citerefentry project='man-pages'><refentrytitle>credentials</refentrytitle><manvolnum>7</manvolnum></citerefentry>, <citerefentry project='man-pages'><refentrytitle>free</refentrytitle><manvolnum>3</manvolnum></citerefentry>, <citerefentry project='man-pages'><refentrytitle>proc</refentrytitle><manvolnum>5</manvolnum></citerefentry>, <citerefentry><refentrytitle>systemd.journald-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry> </para> </refsect1> </refentry>