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2ca620c4ed
In service file, if the file has some of special SMACK label in ExecStart= and systemd has no permission for the special SMACK label then permission error will occurred. To resolve this, systemd should be able to set its SMACK label to something accessible of ExecStart=. So introduce new SmackProcessLabel. If label is specified with SmackProcessLabel= then the child systemd will set its label to that. To successfully execute the ExecStart=, accessible label should be specified with SmackProcessLabel=. Additionally, by SMACK policy, if the file in ExecStart= has no SMACK64EXEC then the executed process will have given label by SmackProcessLabel=. But if the file has SMACK64EXEC then the SMACK64EXEC label will be overridden. [zj: reword man page]
1587 lines
93 KiB
XML
1587 lines
93 KiB
XML
<?xml-stylesheet type="text/xsl" href="http://docbook.sourceforge.net/release/xsl/current/xhtml/docbook.xsl"?>
|
||
<!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 2010 Lennart Poettering
|
||
|
||
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="systemd.exec">
|
||
<refentryinfo>
|
||
<title>systemd.exec</title>
|
||
<productname>systemd</productname>
|
||
|
||
<authorgroup>
|
||
<author>
|
||
<contrib>Developer</contrib>
|
||
<firstname>Lennart</firstname>
|
||
<surname>Poettering</surname>
|
||
<email>lennart@poettering.net</email>
|
||
</author>
|
||
</authorgroup>
|
||
</refentryinfo>
|
||
|
||
<refmeta>
|
||
<refentrytitle>systemd.exec</refentrytitle>
|
||
<manvolnum>5</manvolnum>
|
||
</refmeta>
|
||
|
||
<refnamediv>
|
||
<refname>systemd.exec</refname>
|
||
<refpurpose>Execution environment configuration</refpurpose>
|
||
</refnamediv>
|
||
|
||
<refsynopsisdiv>
|
||
<para><filename><replaceable>service</replaceable>.service</filename>,
|
||
<filename><replaceable>socket</replaceable>.socket</filename>,
|
||
<filename><replaceable>mount</replaceable>.mount</filename>,
|
||
<filename><replaceable>swap</replaceable>.swap</filename></para>
|
||
</refsynopsisdiv>
|
||
|
||
<refsect1>
|
||
<title>Description</title>
|
||
|
||
<para>Unit configuration files for services, sockets,
|
||
mount points, and swap devices share a subset of
|
||
configuration options which define the execution
|
||
environment of spawned processes.</para>
|
||
|
||
<para>This man page lists the configuration options
|
||
shared by these four unit types. See
|
||
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
|
||
for the common options of all unit configuration
|
||
files, and
|
||
<citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
|
||
<citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
|
||
<citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
|
||
and
|
||
<citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>
|
||
for more information on the specific unit
|
||
configuration files. The execution specific
|
||
configuration options are configured in the [Service],
|
||
[Socket], [Mount], or [Swap] sections, depending on the unit
|
||
type.</para>
|
||
</refsect1>
|
||
|
||
<refsect1>
|
||
<title>Options</title>
|
||
|
||
<variablelist class='unit-directives'>
|
||
|
||
<varlistentry>
|
||
<term><varname>WorkingDirectory=</varname></term>
|
||
|
||
<listitem><para>Takes an absolute
|
||
directory path. Sets the working
|
||
directory for executed processes. If
|
||
not set, defaults to the root directory
|
||
when systemd is running as a system
|
||
instance and the respective user's
|
||
home directory if run as
|
||
user.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>RootDirectory=</varname></term>
|
||
|
||
<listitem><para>Takes an absolute
|
||
directory path. Sets the root
|
||
directory for executed processes, with
|
||
the
|
||
<citerefentry project='man-pages'><refentrytitle>chroot</refentrytitle><manvolnum>2</manvolnum></citerefentry>
|
||
system call. If this is used, it must
|
||
be ensured that the process and all
|
||
its auxiliary files are available in
|
||
the <function>chroot()</function>
|
||
jail.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>User=</varname></term>
|
||
<term><varname>Group=</varname></term>
|
||
|
||
<listitem><para>Sets the Unix user
|
||
or group that the processes are executed
|
||
as, respectively. Takes a single user or group
|
||
name or ID as argument. If no group is
|
||
set, the default group of the user is
|
||
chosen.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>SupplementaryGroups=</varname></term>
|
||
|
||
<listitem><para>Sets the supplementary
|
||
Unix groups the processes are executed
|
||
as. This takes a space-separated list
|
||
of group names or IDs. This option may
|
||
be specified more than once in which
|
||
case all listed groups are set as
|
||
supplementary groups. When the empty
|
||
string is assigned the list of
|
||
supplementary groups is reset, and all
|
||
assignments prior to this one will
|
||
have no effect. In any way, this
|
||
option does not override, but extends
|
||
the list of supplementary groups
|
||
configured in the system group
|
||
database for the
|
||
user.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>Nice=</varname></term>
|
||
|
||
<listitem><para>Sets the default nice
|
||
level (scheduling priority) for
|
||
executed processes. Takes an integer
|
||
between -20 (highest priority) and 19
|
||
(lowest priority). See
|
||
<citerefentry><refentrytitle>setpriority</refentrytitle><manvolnum>2</manvolnum></citerefentry>
|
||
for details.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>OOMScoreAdjust=</varname></term>
|
||
|
||
<listitem><para>Sets the adjustment
|
||
level for the Out-Of-Memory killer for
|
||
executed processes. Takes an integer
|
||
between -1000 (to disable OOM killing
|
||
for this process) and 1000 (to make
|
||
killing of this process under memory
|
||
pressure very likely). See <ulink
|
||
url="https://www.kernel.org/doc/Documentation/filesystems/proc.txt">proc.txt</ulink>
|
||
for details.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>IOSchedulingClass=</varname></term>
|
||
|
||
<listitem><para>Sets the IO scheduling
|
||
class for executed processes. Takes an
|
||
integer between 0 and 3 or one of the
|
||
strings <option>none</option>,
|
||
<option>realtime</option>,
|
||
<option>best-effort</option> or
|
||
<option>idle</option>. See
|
||
<citerefentry><refentrytitle>ioprio_set</refentrytitle><manvolnum>2</manvolnum></citerefentry>
|
||
for details.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>IOSchedulingPriority=</varname></term>
|
||
|
||
<listitem><para>Sets the IO scheduling
|
||
priority for executed processes. Takes
|
||
an integer between 0 (highest
|
||
priority) and 7 (lowest priority). The
|
||
available priorities depend on the
|
||
selected IO scheduling class (see
|
||
above). See
|
||
<citerefentry><refentrytitle>ioprio_set</refentrytitle><manvolnum>2</manvolnum></citerefentry>
|
||
for details.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>CPUSchedulingPolicy=</varname></term>
|
||
|
||
<listitem><para>Sets the CPU
|
||
scheduling policy for executed
|
||
processes. Takes one of
|
||
<option>other</option>,
|
||
<option>batch</option>,
|
||
<option>idle</option>,
|
||
<option>fifo</option> or
|
||
<option>rr</option>. See
|
||
<citerefentry><refentrytitle>sched_setscheduler</refentrytitle><manvolnum>2</manvolnum></citerefentry>
|
||
for details.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>CPUSchedulingPriority=</varname></term>
|
||
|
||
<listitem><para>Sets the CPU
|
||
scheduling priority for executed
|
||
processes. The available priority
|
||
range depends on the selected CPU
|
||
scheduling policy (see above). For
|
||
real-time scheduling policies an
|
||
integer between 1 (lowest priority)
|
||
and 99 (highest priority) can be used.
|
||
See <citerefentry><refentrytitle>sched_setscheduler</refentrytitle><manvolnum>2</manvolnum></citerefentry>
|
||
for details.
|
||
</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>CPUSchedulingResetOnFork=</varname></term>
|
||
|
||
<listitem><para>Takes a boolean
|
||
argument. If true, elevated CPU
|
||
scheduling priorities and policies
|
||
will be reset when the executed
|
||
processes fork, and can hence not leak
|
||
into child processes. See
|
||
<citerefentry><refentrytitle>sched_setscheduler</refentrytitle><manvolnum>2</manvolnum></citerefentry>
|
||
for details. Defaults to false.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>CPUAffinity=</varname></term>
|
||
|
||
<listitem><para>Controls the CPU
|
||
affinity of the executed
|
||
processes. Takes a space-separated
|
||
list of CPU indices. This option may
|
||
be specified more than once in which
|
||
case the specificed CPU affinity masks
|
||
are merged. If the empty string is
|
||
assigned, the mask is reset, all
|
||
assignments prior to this will have no
|
||
effect. See
|
||
<citerefentry><refentrytitle>sched_setaffinity</refentrytitle><manvolnum>2</manvolnum></citerefentry>
|
||
for details.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>UMask=</varname></term>
|
||
|
||
<listitem><para>Controls the file mode
|
||
creation mask. Takes an access mode in
|
||
octal notation. See
|
||
<citerefentry><refentrytitle>umask</refentrytitle><manvolnum>2</manvolnum></citerefentry>
|
||
for details. Defaults to
|
||
0022.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>Environment=</varname></term>
|
||
|
||
<listitem><para>Sets environment
|
||
variables for executed
|
||
processes. Takes a space-separated
|
||
list of variable assignments. This
|
||
option may be specified more than once
|
||
in which case all listed variables
|
||
will be set. If the same variable is
|
||
set twice, the later setting will
|
||
override the earlier setting. If the
|
||
empty string is assigned to this
|
||
option, the list of environment
|
||
variables is reset, all prior
|
||
assignments have no effect.
|
||
Variable expansion is not performed
|
||
inside the strings, however, specifier
|
||
expansion is possible. The $ character has
|
||
no special meaning.
|
||
If you need to assign a value containing spaces
|
||
to a variable, use double quotes (")
|
||
for the assignment.</para>
|
||
|
||
<para>Example:
|
||
<programlisting>Environment="VAR1=word1 word2" VAR2=word3 "VAR3=$word 5 6"</programlisting>
|
||
gives three variables <literal>VAR1</literal>,
|
||
<literal>VAR2</literal>, <literal>VAR3</literal>
|
||
with the values <literal>word1 word2</literal>,
|
||
<literal>word3</literal>, <literal>$word 5 6</literal>.
|
||
</para>
|
||
|
||
<para>
|
||
See
|
||
<citerefentry project='man-pages'><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry>
|
||
for details about environment variables.</para></listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><varname>EnvironmentFile=</varname></term>
|
||
<listitem><para>Similar to
|
||
<varname>Environment=</varname> but
|
||
reads the environment variables from a
|
||
text file. The text file should
|
||
contain new-line-separated variable
|
||
assignments. Empty lines and lines
|
||
starting with ; or # will be ignored,
|
||
which may be used for commenting. A line
|
||
ending with a backslash will be concatenated
|
||
with the following one, allowing multiline variable
|
||
definitions. The parser strips leading
|
||
and trailing whitespace from the values
|
||
of assignments, unless you use
|
||
double quotes (").</para>
|
||
|
||
<para>The argument passed should be an
|
||
absolute filename or wildcard
|
||
expression, optionally prefixed with
|
||
<literal>-</literal>, which indicates
|
||
that if the file does not exist, it
|
||
will not be read and no error or warning
|
||
message is logged. This option may be
|
||
specified more than once in which case
|
||
all specified files are read. If the
|
||
empty string is assigned to this
|
||
option, the list of file to read is
|
||
reset, all prior assignments have no
|
||
effect.</para>
|
||
|
||
<para>The files listed with this
|
||
directive will be read shortly before
|
||
the process is executed (more
|
||
specifically, after all
|
||
processes from a previous unit state
|
||
terminated. This means you can
|
||
generate these files in one unit
|
||
state, and read it with this option in
|
||
the next). Settings from these files
|
||
override settings made with
|
||
<varname>Environment=</varname>. If
|
||
the same variable is set twice from
|
||
these files, the files will be read in
|
||
the order they are specified and the
|
||
later setting will override the
|
||
earlier setting.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>StandardInput=</varname></term>
|
||
<listitem><para>Controls where file
|
||
descriptor 0 (STDIN) of the executed
|
||
processes is connected to. Takes one
|
||
of <option>null</option>,
|
||
<option>tty</option>,
|
||
<option>tty-force</option>,
|
||
<option>tty-fail</option> or
|
||
<option>socket</option>.</para>
|
||
|
||
<para>If <option>null</option> is
|
||
selected, standard input will be
|
||
connected to
|
||
<filename>/dev/null</filename>,
|
||
i.e. all read attempts by the process
|
||
will result in immediate EOF.</para>
|
||
|
||
<para>If <option>tty</option> is
|
||
selected, standard input is connected
|
||
to a TTY (as configured by
|
||
<varname>TTYPath=</varname>, see
|
||
below) and the executed process
|
||
becomes the controlling process of the
|
||
terminal. If the terminal is already
|
||
being controlled by another process,
|
||
the executed process waits until the
|
||
current controlling process releases
|
||
the terminal.</para>
|
||
|
||
<para><option>tty-force</option> is similar
|
||
to <option>tty</option>, but the
|
||
executed process is forcefully and
|
||
immediately made the controlling
|
||
process of the terminal, potentially
|
||
removing previous controlling
|
||
processes from the
|
||
terminal.</para>
|
||
|
||
<para><option>tty-fail</option> is
|
||
similar to <option>tty</option> but if
|
||
the terminal already has a controlling
|
||
process start-up of the executed
|
||
process fails.</para>
|
||
|
||
<para>The <option>socket</option>
|
||
option is only valid in
|
||
socket-activated services, and only
|
||
when the socket configuration file
|
||
(see
|
||
<citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>
|
||
for details) specifies a single socket
|
||
only. If this option is set, standard
|
||
input will be connected to the socket
|
||
the service was activated from, which
|
||
is primarily useful for compatibility
|
||
with daemons designed for use with the
|
||
traditional
|
||
<citerefentry><refentrytitle>inetd</refentrytitle><manvolnum>8</manvolnum></citerefentry>
|
||
daemon.</para>
|
||
|
||
<para>This setting defaults to
|
||
<option>null</option>.</para></listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><varname>StandardOutput=</varname></term>
|
||
<listitem><para>Controls where file
|
||
descriptor 1 (STDOUT) of the executed
|
||
processes is connected to. Takes one
|
||
of <option>inherit</option>,
|
||
<option>null</option>,
|
||
<option>tty</option>,
|
||
<option>journal</option>,
|
||
<option>syslog</option>,
|
||
<option>kmsg</option>,
|
||
<option>journal+console</option>,
|
||
<option>syslog+console</option>,
|
||
<option>kmsg+console</option> or
|
||
<option>socket</option>.</para>
|
||
|
||
<para><option>inherit</option>
|
||
duplicates the file descriptor of
|
||
standard input for standard
|
||
output.</para>
|
||
|
||
<para><option>null</option> connects
|
||
standard output to
|
||
<filename>/dev/null</filename>,
|
||
i.e. everything written to it will be
|
||
lost.</para>
|
||
|
||
<para><option>tty</option> connects
|
||
standard output to a tty (as
|
||
configured via
|
||
<varname>TTYPath=</varname>, see
|
||
below). If the TTY is used for output
|
||
only, the executed process will not
|
||
become the controlling process of the
|
||
terminal, and will not fail or wait
|
||
for other processes to release the
|
||
terminal.</para>
|
||
|
||
<para><option>journal</option>
|
||
connects standard output with the
|
||
journal which is accessible via
|
||
<citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>.
|
||
Note that everything that is written
|
||
to syslog or kmsg (see below) is
|
||
implicitly stored in the journal as
|
||
well, the specific two options listed
|
||
below are hence supersets of this
|
||
one.</para>
|
||
|
||
<para><option>syslog</option> connects
|
||
standard output to the <citerefentry
|
||
project='man-pages'><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>
|
||
system syslog service, in addition to
|
||
the journal. Note that the journal
|
||
daemon is usually configured to
|
||
forward everything it receives to
|
||
syslog anyway, in which case this
|
||
option is no different from
|
||
<option>journal</option>.</para>
|
||
|
||
<para><option>kmsg</option> connects
|
||
standard output with the kernel log
|
||
buffer which is accessible via
|
||
<citerefentry
|
||
project='man-pages'><refentrytitle>dmesg</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
|
||
in addition to the journal. The
|
||
journal daemon might be configured to
|
||
send all logs to kmsg anyway, in which
|
||
case this option is no different from
|
||
<option>journal</option>.</para>
|
||
|
||
<para><option>journal+console</option>,
|
||
<option>syslog+console</option> and
|
||
<option>kmsg+console</option> work in
|
||
a similar way as the three options
|
||
above but copy the output to the
|
||
system console as well.</para>
|
||
|
||
<para><option>socket</option> connects
|
||
standard output to a socket acquired
|
||
via socket activation. The semantics
|
||
are similar to the same option of
|
||
<varname>StandardInput=</varname>.</para>
|
||
|
||
<para>This setting defaults to the
|
||
value set with
|
||
<option>DefaultStandardOutput=</option>
|
||
in
|
||
<citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
|
||
which defaults to
|
||
<option>journal</option>.</para></listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><varname>StandardError=</varname></term>
|
||
<listitem><para>Controls where file
|
||
descriptor 2 (STDERR) of the
|
||
executed processes is connected to.
|
||
The available options are identical to
|
||
those of
|
||
<varname>StandardOutput=</varname>,
|
||
with one exception: if set to
|
||
<option>inherit</option> the file
|
||
descriptor used for standard output is
|
||
duplicated for standard error. This
|
||
setting defaults to the value set with
|
||
<option>DefaultStandardError=</option>
|
||
in
|
||
<citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
|
||
which defaults to
|
||
<option>inherit</option>.</para></listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><varname>TTYPath=</varname></term>
|
||
<listitem><para>Sets the terminal
|
||
device node to use if standard input, output,
|
||
or error are connected to a
|
||
TTY (see above). Defaults to
|
||
<filename>/dev/console</filename>.</para></listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><varname>TTYReset=</varname></term>
|
||
<listitem><para>Reset the terminal
|
||
device specified with
|
||
<varname>TTYPath=</varname> before and
|
||
after execution. Defaults to
|
||
<literal>no</literal>.</para></listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><varname>TTYVHangup=</varname></term>
|
||
<listitem><para>Disconnect all clients
|
||
which have opened the terminal device
|
||
specified with
|
||
<varname>TTYPath=</varname>
|
||
before and after execution. Defaults
|
||
to
|
||
<literal>no</literal>.</para></listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><varname>TTYVTDisallocate=</varname></term>
|
||
<listitem><para>If the terminal
|
||
device specified with
|
||
<varname>TTYPath=</varname> is a
|
||
virtual console terminal, try to
|
||
deallocate the TTY before and after
|
||
execution. This ensures that the
|
||
screen and scrollback buffer is
|
||
cleared. Defaults to
|
||
<literal>no</literal>.</para></listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><varname>SyslogIdentifier=</varname></term>
|
||
<listitem><para>Sets the process name
|
||
to prefix log lines sent to the
|
||
logging system or the kernel log
|
||
buffer with. If not set, defaults to
|
||
the process name of the executed
|
||
process. This option is only useful
|
||
when
|
||
<varname>StandardOutput=</varname> or
|
||
<varname>StandardError=</varname> are
|
||
set to <option>syslog</option>,
|
||
<option>journal</option> or
|
||
<option>kmsg</option> (or to the same
|
||
settings in combination with
|
||
<option>+console</option>).</para></listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><varname>SyslogFacility=</varname></term>
|
||
<listitem><para>Sets the syslog
|
||
facility to use when logging to
|
||
syslog. One of <option>kern</option>,
|
||
<option>user</option>,
|
||
<option>mail</option>,
|
||
<option>daemon</option>,
|
||
<option>auth</option>,
|
||
<option>syslog</option>,
|
||
<option>lpr</option>,
|
||
<option>news</option>,
|
||
<option>uucp</option>,
|
||
<option>cron</option>,
|
||
<option>authpriv</option>,
|
||
<option>ftp</option>,
|
||
<option>local0</option>,
|
||
<option>local1</option>,
|
||
<option>local2</option>,
|
||
<option>local3</option>,
|
||
<option>local4</option>,
|
||
<option>local5</option>,
|
||
<option>local6</option> or
|
||
<option>local7</option>. See
|
||
<citerefentry project='man-pages'><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>
|
||
for details. This option is only
|
||
useful when
|
||
<varname>StandardOutput=</varname> or
|
||
<varname>StandardError=</varname> are
|
||
set to <option>syslog</option>.
|
||
Defaults to
|
||
<option>daemon</option>.</para></listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><varname>SyslogLevel=</varname></term>
|
||
<listitem><para>Default syslog level
|
||
to use when logging to syslog or the
|
||
kernel log buffer. One of
|
||
<option>emerg</option>,
|
||
<option>alert</option>,
|
||
<option>crit</option>,
|
||
<option>err</option>,
|
||
<option>warning</option>,
|
||
<option>notice</option>,
|
||
<option>info</option>,
|
||
<option>debug</option>. See
|
||
<citerefentry project='man-pages'><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>
|
||
for details. This option is only
|
||
useful when
|
||
<varname>StandardOutput=</varname> or
|
||
<varname>StandardError=</varname> are
|
||
set to <option>syslog</option> or
|
||
<option>kmsg</option>. Note that
|
||
individual lines output by the daemon
|
||
might be prefixed with a different log
|
||
level which can be used to override
|
||
the default log level specified
|
||
here. The interpretation of these
|
||
prefixes may be disabled with
|
||
<varname>SyslogLevelPrefix=</varname>,
|
||
see below. For details see
|
||
<citerefentry><refentrytitle>sd-daemon</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
|
||
|
||
Defaults to
|
||
<option>info</option>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>SyslogLevelPrefix=</varname></term>
|
||
<listitem><para>Takes a boolean
|
||
argument. If true and
|
||
<varname>StandardOutput=</varname> or
|
||
<varname>StandardError=</varname> are
|
||
set to <option>syslog</option>,
|
||
<option>kmsg</option> or
|
||
<option>journal</option>, log lines
|
||
written by the executed process that
|
||
are prefixed with a log level will be
|
||
passed on to syslog with this log
|
||
level set but the prefix removed. If
|
||
set to false, the interpretation of
|
||
these prefixes is disabled and the
|
||
logged lines are passed on as-is. For
|
||
details about this prefixing see
|
||
<citerefentry><refentrytitle>sd-daemon</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
|
||
Defaults to true.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>TimerSlackNSec=</varname></term>
|
||
<listitem><para>Sets the timer slack
|
||
in nanoseconds for the executed
|
||
processes. The timer slack controls
|
||
the accuracy of wake-ups triggered by
|
||
timers. See
|
||
<citerefentry><refentrytitle>prctl</refentrytitle><manvolnum>2</manvolnum></citerefentry>
|
||
for more information. Note that in
|
||
contrast to most other time span
|
||
definitions this parameter takes an
|
||
integer value in nano-seconds if no
|
||
unit is specified. The usual time
|
||
units are understood
|
||
too.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>LimitCPU=</varname></term>
|
||
<term><varname>LimitFSIZE=</varname></term>
|
||
<term><varname>LimitDATA=</varname></term>
|
||
<term><varname>LimitSTACK=</varname></term>
|
||
<term><varname>LimitCORE=</varname></term>
|
||
<term><varname>LimitRSS=</varname></term>
|
||
<term><varname>LimitNOFILE=</varname></term>
|
||
<term><varname>LimitAS=</varname></term>
|
||
<term><varname>LimitNPROC=</varname></term>
|
||
<term><varname>LimitMEMLOCK=</varname></term>
|
||
<term><varname>LimitLOCKS=</varname></term>
|
||
<term><varname>LimitSIGPENDING=</varname></term>
|
||
<term><varname>LimitMSGQUEUE=</varname></term>
|
||
<term><varname>LimitNICE=</varname></term>
|
||
<term><varname>LimitRTPRIO=</varname></term>
|
||
<term><varname>LimitRTTIME=</varname></term>
|
||
<listitem><para>These settings control
|
||
various resource limits for executed
|
||
processes. See
|
||
<citerefentry><refentrytitle>setrlimit</refentrytitle><manvolnum>2</manvolnum></citerefentry>
|
||
for details. Use the string
|
||
<varname>infinity</varname> to
|
||
configure no limit on a specific
|
||
resource.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>PAMName=</varname></term>
|
||
<listitem><para>Sets the PAM service
|
||
name to set up a session as. If set,
|
||
the executed process will be
|
||
registered as a PAM session under the
|
||
specified service name. This is only
|
||
useful in conjunction with the
|
||
<varname>User=</varname> setting. If
|
||
not set, no PAM session will be opened
|
||
for the executed processes. See
|
||
<citerefentry project='man-pages'><refentrytitle>pam</refentrytitle><manvolnum>8</manvolnum></citerefentry>
|
||
for details.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>CapabilityBoundingSet=</varname></term>
|
||
|
||
<listitem><para>Controls which
|
||
capabilities to include in the
|
||
capability bounding set for the
|
||
executed process. See
|
||
<citerefentry project='man-pages'><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry>
|
||
for details. Takes a whitespace-separated
|
||
list of capability names as read by
|
||
<citerefentry><refentrytitle>cap_from_name</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
|
||
e.g. <constant>CAP_SYS_ADMIN</constant>,
|
||
<constant>CAP_DAC_OVERRIDE</constant>,
|
||
<constant>CAP_SYS_PTRACE</constant>.
|
||
Capabilities listed will be included
|
||
in the bounding set, all others are
|
||
removed. If the list of capabilities
|
||
is prefixed with <literal>~</literal>,
|
||
all but the listed capabilities will
|
||
be included, the effect of the
|
||
assignment inverted. Note that this
|
||
option also affects the respective
|
||
capabilities in the effective,
|
||
permitted and inheritable capability
|
||
sets, on top of what
|
||
<varname>Capabilities=</varname>
|
||
does. If this option is not used, the
|
||
capability bounding set is not
|
||
modified on process execution, hence
|
||
no limits on the capabilities of the
|
||
process are enforced. This option may
|
||
appear more than once in which case
|
||
the bounding sets are merged. If the
|
||
empty string is assigned to this
|
||
option, the bounding set is reset to
|
||
the empty capability set, and all
|
||
prior settings have no effect. If set
|
||
to <literal>~</literal> (without any
|
||
further argument), the bounding set is
|
||
reset to the full set of available
|
||
capabilities, also undoing any
|
||
previous settings.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>SecureBits=</varname></term>
|
||
<listitem><para>Controls the secure
|
||
bits set for the executed process.
|
||
Takes a space-separated combination of
|
||
options from the following list:
|
||
<option>keep-caps</option>,
|
||
<option>keep-caps-locked</option>,
|
||
<option>no-setuid-fixup</option>,
|
||
<option>no-setuid-fixup-locked</option>,
|
||
<option>noroot</option>, and
|
||
<option>noroot-locked</option>. This
|
||
option may appear more than once in
|
||
which case the secure bits are ORed.
|
||
If the empty string is assigned to
|
||
this option, the bits are reset to 0.
|
||
See <citerefentry
|
||
project='man-pages'><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry>
|
||
for details.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>Capabilities=</varname></term>
|
||
<listitem><para>Controls the
|
||
<citerefentry project='man-pages'><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry>
|
||
set for the executed process. Take a
|
||
capability string describing the
|
||
effective, permitted and inherited
|
||
capability sets as documented in
|
||
<citerefentry><refentrytitle>cap_from_text</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
|
||
Note that these capability sets are
|
||
usually influenced (and filtered) by the capabilities
|
||
attached to the executed file. Due to
|
||
that
|
||
<varname>CapabilityBoundingSet=</varname>
|
||
is probably a much more useful
|
||
setting.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>ReadWriteDirectories=</varname></term>
|
||
<term><varname>ReadOnlyDirectories=</varname></term>
|
||
<term><varname>InaccessibleDirectories=</varname></term>
|
||
|
||
<listitem><para>Sets up a new file
|
||
system namespace for executed
|
||
processes. These options may be used
|
||
to limit access a process might have
|
||
to the main file system
|
||
hierarchy. Each setting takes a
|
||
space-separated list of absolute
|
||
directory paths. Directories listed in
|
||
<varname>ReadWriteDirectories=</varname>
|
||
are accessible from within the
|
||
namespace with the same access rights
|
||
as from outside. Directories listed in
|
||
<varname>ReadOnlyDirectories=</varname>
|
||
are accessible for reading only,
|
||
writing will be refused even if the
|
||
usual file access controls would
|
||
permit this. Directories listed in
|
||
<varname>InaccessibleDirectories=</varname>
|
||
will be made inaccessible for
|
||
processes inside the namespace. Note
|
||
that restricting access with these
|
||
options does not extend to submounts
|
||
of a directory that are created later
|
||
on. These options may be specified
|
||
more than once in which case all
|
||
directories listed will have limited
|
||
access from within the namespace. If
|
||
the empty string is assigned to this
|
||
option, the specific list is reset,
|
||
and all prior assignments have no
|
||
effect.</para>
|
||
<para>Paths in
|
||
<varname>ReadOnlyDirectories=</varname>
|
||
and
|
||
<varname>InaccessibleDirectories=</varname>
|
||
may be prefixed with
|
||
<literal>-</literal>, in which case
|
||
they will be ignored when they do not
|
||
exist. Note that using this
|
||
setting will disconnect propagation of
|
||
mounts from the service to the host
|
||
(propagation in the opposite direction
|
||
continues to work). This means that
|
||
this setting may not be used for
|
||
services which shall be able to
|
||
install mount points in the main mount
|
||
namespace.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>PrivateTmp=</varname></term>
|
||
|
||
<listitem><para>Takes a boolean
|
||
argument. If true, sets up a new file
|
||
system namespace for the executed
|
||
processes and mounts private
|
||
<filename>/tmp</filename> and
|
||
<filename>/var/tmp</filename>
|
||
directories inside it that is not
|
||
shared by processes outside of the
|
||
namespace. This is useful to secure
|
||
access to temporary files of the
|
||
process, but makes sharing between
|
||
processes via
|
||
<filename>/tmp</filename> or
|
||
<filename>/var/tmp</filename>
|
||
impossible. If this is enabled, all
|
||
temporary files created by a service
|
||
in these directories will be removed
|
||
after the service is stopped. Defaults
|
||
to false. It is possible to run two or
|
||
more units within the same private
|
||
<filename>/tmp</filename> and
|
||
<filename>/var/tmp</filename>
|
||
namespace by using the
|
||
<varname>JoinsNamespaceOf=</varname>
|
||
directive, see
|
||
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
|
||
for details. Note that using this
|
||
setting will disconnect propagation of
|
||
mounts from the service to the host
|
||
(propagation in the opposite direction
|
||
continues to work). This means that
|
||
this setting may not be used for
|
||
services which shall be able to install
|
||
mount points in the main mount
|
||
namespace.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>PrivateDevices=</varname></term>
|
||
|
||
<listitem><para>Takes a boolean
|
||
argument. If true, sets up a new /dev
|
||
namespace for the executed processes
|
||
and only adds API pseudo devices such
|
||
as <filename>/dev/null</filename>,
|
||
<filename>/dev/zero</filename> or
|
||
<filename>/dev/random</filename> (as
|
||
well as the pseudo TTY subsystem) to
|
||
it, but no physical devices such as
|
||
<filename>/dev/sda</filename>. This is
|
||
useful to securely turn off physical
|
||
device access by the executed
|
||
process. Defaults to false. Enabling
|
||
this option will also remove
|
||
<constant>CAP_MKNOD</constant> from
|
||
the capability bounding set for the
|
||
unit (see above), and set
|
||
<varname>DevicePolicy=closed</varname>
|
||
(see
|
||
<citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>
|
||
for details). Note that using this
|
||
setting will disconnect propagation of
|
||
mounts from the service to the host
|
||
(propagation in the opposite direction
|
||
continues to work). This means that
|
||
this setting may not be used for
|
||
services which shall be able to
|
||
install mount points in the main mount
|
||
namespace.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>PrivateNetwork=</varname></term>
|
||
|
||
<listitem><para>Takes a boolean
|
||
argument. If true, sets up a new
|
||
network namespace for the executed
|
||
processes and configures only the
|
||
loopback network device
|
||
<literal>lo</literal> inside it. No
|
||
other network devices will be
|
||
available to the executed process.
|
||
This is useful to securely turn off
|
||
network access by the executed
|
||
process. Defaults to false. It is
|
||
possible to run two or more units
|
||
within the same private network
|
||
namespace by using the
|
||
<varname>JoinsNamespaceOf=</varname>
|
||
directive, see
|
||
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
|
||
for details. Note that this option
|
||
will disconnect all socket families
|
||
from the host, this includes
|
||
AF_NETLINK and AF_UNIX. The latter has
|
||
the effect that AF_UNIX sockets in the
|
||
abstract socket namespace will become
|
||
unavailable to the processes (however,
|
||
those located in the file system will
|
||
continue to be
|
||
accessible).</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>ProtectSystem=</varname></term>
|
||
|
||
<listitem><para>Takes a boolean
|
||
argument or
|
||
<literal>full</literal>. If true,
|
||
mounts the <filename>/usr</filename>
|
||
directory read-only for processes
|
||
invoked by this unit. If set to
|
||
<literal>full</literal>, the
|
||
<filename>/etc</filename> directory is mounted
|
||
read-only, too. This setting ensures
|
||
that any modification of the vendor
|
||
supplied operating system (and
|
||
optionally its configuration) is
|
||
prohibited for the service. It is
|
||
recommended to enable this setting for
|
||
all long-running services, unless they
|
||
are involved with system updates or
|
||
need to modify the operating system in
|
||
other ways. Note however that
|
||
processes retaining the CAP_SYS_ADMIN
|
||
capability can undo the effect of this
|
||
setting. This setting is hence
|
||
particularly useful for daemons which
|
||
have this capability removed, for
|
||
example with
|
||
<varname>CapabilityBoundingSet=</varname>. Defaults
|
||
to off.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>ProtectHome=</varname></term>
|
||
|
||
<listitem><para>Takes a boolean
|
||
argument or
|
||
<literal>read-only</literal>. If true,
|
||
the directories
|
||
<filename>/home</filename> and
|
||
<filename>/run/user</filename> are
|
||
made inaccessible and empty for
|
||
processes invoked by this unit. If set
|
||
to <literal>read-only</literal>, the
|
||
two directories are made read-only
|
||
instead. It is recommended to enable
|
||
this setting for all long-running
|
||
services (in particular network-facing
|
||
ones), to ensure they cannot get access
|
||
to private user data, unless the
|
||
services actually require access to
|
||
the user's private data. Note however
|
||
that processes retaining the
|
||
CAP_SYS_ADMIN capability can undo the
|
||
effect of this setting. This setting
|
||
is hence particularly useful for
|
||
daemons which have this capability
|
||
removed, for example with
|
||
<varname>CapabilityBoundingSet=</varname>. Defaults
|
||
to off.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>MountFlags=</varname></term>
|
||
|
||
<listitem><para>Takes a mount
|
||
propagation flag:
|
||
<option>shared</option>,
|
||
<option>slave</option> or
|
||
<option>private</option>, which
|
||
control whether mounts in the file
|
||
system namespace set up for this
|
||
unit's processes will receive or
|
||
propagate mounts or unmounts. See
|
||
<citerefentry><refentrytitle>mount</refentrytitle><manvolnum>2</manvolnum></citerefentry>
|
||
for details. Defaults to
|
||
<option>shared</option>. Use
|
||
<option>shared</option> to ensure that
|
||
mounts and unmounts are propagated
|
||
from the host to the container and
|
||
vice versa. Use <option>slave</option>
|
||
to run processes so that none of their
|
||
mounts and unmounts will propagate to
|
||
the host. Use <option>private</option>
|
||
to also ensure that no mounts and
|
||
unmounts from the host will propagate
|
||
into the unit processes'
|
||
namespace. Note that
|
||
<option>slave</option> means that file
|
||
systems mounted on the host might stay
|
||
mounted continuously in the unit's
|
||
namespace, and thus keep the device
|
||
busy. Note that the file system
|
||
namespace related options
|
||
(<varname>PrivateTmp=</varname>,
|
||
<varname>PrivateDevices=</varname>,
|
||
<varname>ProtectSystem=</varname>,
|
||
<varname>ProtectHome=</varname>,
|
||
<varname>ReadOnlyDirectories=</varname>,
|
||
<varname>InaccessibleDirectories=</varname>
|
||
and
|
||
<varname>ReadWriteDirectories=</varname>)
|
||
require that mount and unmount
|
||
propagation from the unit's file
|
||
system namespace is disabled, and
|
||
hence downgrade
|
||
<option>shared</option> to
|
||
<option>slave</option>.
|
||
</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>UtmpIdentifier=</varname></term>
|
||
|
||
<listitem><para>Takes a four
|
||
character identifier string for an
|
||
utmp/wtmp entry for this service. This
|
||
should only be set for services such
|
||
as <command>getty</command>
|
||
implementations where utmp/wtmp
|
||
entries must be created and cleared
|
||
before and after execution. If the
|
||
configured string is longer than four
|
||
characters, it is truncated and the
|
||
terminal four characters are
|
||
used. This setting interprets %I style
|
||
string replacements. This setting is
|
||
unset by default, i.e. no utmp/wtmp
|
||
entries are created or cleaned up for
|
||
this service.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>SELinuxContext=</varname></term>
|
||
|
||
<listitem><para>Set the SELinux
|
||
security context of the executed
|
||
process. If set, this will override
|
||
the automated domain
|
||
transition. However, the policy still
|
||
needs to autorize the transition. This
|
||
directive is ignored if SELinux is
|
||
disabled. If prefixed by
|
||
<literal>-</literal>, all errors will
|
||
be ignored. See
|
||
<citerefentry><refentrytitle>setexeccon</refentrytitle><manvolnum>3</manvolnum></citerefentry>
|
||
for details.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>AppArmorProfile=</varname></term>
|
||
|
||
<listitem><para>Takes a profile name as argument.
|
||
The process executed by the unit will switch to
|
||
this profile when started. Profiles must already
|
||
be loaded in the kernel, or the unit will fail.
|
||
This result in a non operation if AppArmor is not
|
||
enabled. If prefixed by <literal>-</literal>, all errors
|
||
will be ignored.
|
||
</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>SmackProcessLabel=</varname></term>
|
||
|
||
<listitem><para>Takes a
|
||
<option>SMACK64</option> security
|
||
label as argument. The process
|
||
executed by the unit will be started
|
||
under this label and SMACK will decide
|
||
whether the processes is allowed to
|
||
run or not based on it. The process
|
||
will continue to run under the label
|
||
specified here unless the executable
|
||
has its own
|
||
<option>SMACK64EXEC</option> label, in
|
||
which case the process will transition
|
||
to run under that label. When not
|
||
specified, the label that systemd is
|
||
running under is used. This directive
|
||
is ignored if SMACK is
|
||
disabled.</para>
|
||
|
||
<para>The value may be prefixed by
|
||
<literal>-</literal>, in which case
|
||
all errors will be ignored. An empty
|
||
value may be specified to unset
|
||
previous assignments.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>IgnoreSIGPIPE=</varname></term>
|
||
|
||
<listitem><para>Takes a boolean
|
||
argument. If true, causes <constant>SIGPIPE</constant> to be
|
||
ignored in the executed
|
||
process. Defaults to true because
|
||
<constant>SIGPIPE</constant> generally is useful only in
|
||
shell pipelines.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>NoNewPrivileges=</varname></term>
|
||
|
||
<listitem><para>Takes a boolean
|
||
argument. If true, ensures that the
|
||
service process and all its children
|
||
can never gain new privileges. This
|
||
option is more powerful than the respective
|
||
secure bits flags (see above), as it
|
||
also prohibits UID changes of any
|
||
kind. This is the simplest, most
|
||
effective way to ensure that a process
|
||
and its children can never elevate
|
||
privileges again.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>SystemCallFilter=</varname></term>
|
||
|
||
<listitem><para>Takes a
|
||
space-separated list of system call
|
||
names. If this setting is used, all
|
||
system calls executed by the unit
|
||
processes except for the listed ones
|
||
will result in immediate process
|
||
termination with the
|
||
<constant>SIGSYS</constant> signal
|
||
(whitelisting). If the first character
|
||
of the list is <literal>~</literal>,
|
||
the effect is inverted: only the
|
||
listed system calls will result in
|
||
immediate process termination
|
||
(blacklisting). If running in user
|
||
mode and this option is used,
|
||
<varname>NoNewPrivileges=yes</varname>
|
||
is implied. This feature makes use of the
|
||
Secure Computing Mode 2 interfaces of
|
||
the kernel ('seccomp filtering') and
|
||
is useful for enforcing a minimal
|
||
sandboxing environment. Note that the
|
||
<function>execve</function>,
|
||
<function>rt_sigreturn</function>,
|
||
<function>sigreturn</function>,
|
||
<function>exit_group</function>,
|
||
<function>exit</function> system calls
|
||
are implicitly whitelisted and do not
|
||
need to be listed explicitly. This
|
||
option may be specified more than once
|
||
in which case the filter masks are
|
||
merged. If the empty string is
|
||
assigned, the filter is reset, all
|
||
prior assignments will have no
|
||
effect.</para>
|
||
|
||
<para>If you specify both types of
|
||
this option (i.e. whitelisting and
|
||
blacklisting), the first encountered
|
||
will take precedence and will dictate
|
||
the default action (termination or
|
||
approval of a system call). Then the
|
||
next occurrences of this option will
|
||
add or delete the listed system calls
|
||
from the set of the filtered system
|
||
calls, depending of its type and the
|
||
default action. (For example, if you have started
|
||
with a whitelisting of
|
||
<function>read</function> and
|
||
<function>write</function>, and right
|
||
after it add a blacklisting of
|
||
<function>write</function>, then
|
||
<function>write</function> will be
|
||
removed from the set.)
|
||
</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>SystemCallErrorNumber=</varname></term>
|
||
|
||
<listitem><para>Takes an
|
||
<literal>errno</literal> error number
|
||
name to return when the system call
|
||
filter configured with
|
||
<varname>SystemCallFilter=</varname>
|
||
is triggered, instead of terminating
|
||
the process immediately. Takes an
|
||
error name such as
|
||
<constant>EPERM</constant>,
|
||
<constant>EACCES</constant> or
|
||
<constant>EUCLEAN</constant>. When this
|
||
setting is not used, or when the empty
|
||
string is assigned, the process will be
|
||
terminated immediately when the filter
|
||
is triggered.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>SystemCallArchitectures=</varname></term>
|
||
|
||
<listitem><para>Takes a space
|
||
separated list of architecture
|
||
identifiers to include in the system
|
||
call filter. The known architecture
|
||
identifiers are
|
||
<constant>x86</constant>,
|
||
<constant>x86-64</constant>,
|
||
<constant>x32</constant>,
|
||
<constant>arm</constant> as well as
|
||
the special identifier
|
||
<constant>native</constant>. Only
|
||
system calls of the specified
|
||
architectures will be permitted to
|
||
processes of this unit. This is an
|
||
effective way to disable compatibility
|
||
with non-native architectures for
|
||
processes, for example to prohibit
|
||
execution of 32-bit x86 binaries on
|
||
64-bit x86-64 systems. The special
|
||
<constant>native</constant> identifier
|
||
implicitly maps to the native
|
||
architecture of the system (or more
|
||
strictly: to the architecture the
|
||
system manager is compiled for). If
|
||
running in user mode and this option
|
||
is used,
|
||
<varname>NoNewPrivileges=yes</varname>
|
||
is implied. Note that setting this
|
||
option to a non-empty list implies
|
||
that <constant>native</constant> is
|
||
included too. By default, this option
|
||
is set to the empty list, i.e. no
|
||
architecture system call filtering is
|
||
applied.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>RestrictAddressFamilies=</varname></term>
|
||
|
||
<listitem><para>Restricts the set of
|
||
socket address families accessible to
|
||
the processes of this unit. Takes a
|
||
space-separated list of address family
|
||
names to whitelist, such as
|
||
<constant>AF_UNIX</constant>,
|
||
<constant>AF_INET</constant> or
|
||
<constant>AF_INET6</constant>. When
|
||
prefixed with <constant>~</constant>
|
||
the listed address families will be
|
||
applied as blacklist, otherwise as
|
||
whitelist. Note that this restricts
|
||
access to the
|
||
<citerefentry><refentrytitle>socket</refentrytitle><manvolnum>2</manvolnum></citerefentry>
|
||
system call only. Sockets passed into
|
||
the process by other means (for
|
||
example, by using socket activation
|
||
with socket units, see
|
||
<citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>)
|
||
are unaffected. Also, sockets created
|
||
with <function>socketpair()</function>
|
||
(which creates connected AF_UNIX
|
||
sockets only) are unaffected. Note
|
||
that this option has no effect on
|
||
32-bit x86 and is ignored (but works
|
||
correctly on x86-64). If running in user
|
||
mode and this option is used,
|
||
<varname>NoNewPrivileges=yes</varname>
|
||
is implied. By default, no
|
||
restriction applies, all address
|
||
families are accessible to
|
||
processes. If assigned the empty
|
||
string, any previous list changes are
|
||
undone.</para>
|
||
|
||
<para>Use this option to limit
|
||
exposure of processes to remote
|
||
systems, in particular via exotic
|
||
network protocols. Note that in most
|
||
cases, the local
|
||
<constant>AF_UNIX</constant> address
|
||
family should be included in the
|
||
configured whitelist as it is
|
||
frequently used for local
|
||
communication, including for
|
||
<citerefentry><refentrytitle>syslog</refentrytitle><manvolnum>2</manvolnum></citerefentry>
|
||
logging.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>Personality=</varname></term>
|
||
|
||
<listitem><para>Controls which
|
||
kernel architecture
|
||
<citerefentry><refentrytitle>uname</refentrytitle><manvolnum>2</manvolnum></citerefentry>
|
||
shall report, when invoked by unit
|
||
processes. Takes one of
|
||
<constant>x86</constant> and
|
||
<constant>x86-64</constant>. This is
|
||
useful when running 32-bit services on
|
||
a 64-bit host system. If not specified,
|
||
the personality is left unmodified and
|
||
thus reflects the personality of the
|
||
host system's
|
||
kernel.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>RuntimeDirectory=</varname></term>
|
||
<term><varname>RuntimeDirectoryMode=</varname></term>
|
||
|
||
<listitem><para>Takes a list of
|
||
directory names. If set, one or more
|
||
directories by the specified names
|
||
will be created below
|
||
<filename>/run</filename> (for system
|
||
services) or below
|
||
<varname>$XDG_RUNTIME_DIR</varname>
|
||
(for user services) when the unit is
|
||
started, and removed when the unit is
|
||
stopped. The directories will have the
|
||
access mode specified in
|
||
<varname>RuntimeDirectoryMode=</varname>,
|
||
and will be owned by the user and
|
||
group specified in
|
||
<varname>User=</varname> and
|
||
<varname>Group=</varname>. Use this to
|
||
manage one or more runtime directories
|
||
of the unit and bind their lifetime to
|
||
the daemon runtime. The specified
|
||
directory names must be relative, and
|
||
may not include a
|
||
<literal>/</literal>, i.e. must refer
|
||
to simple directories to create or
|
||
remove. This is particularly useful
|
||
for unprivileged daemons that cannot
|
||
create runtime directories in
|
||
<filename>/run</filename> due to lack
|
||
of privileges, and to make sure the
|
||
runtime directory is cleaned up
|
||
automatically after use. For runtime
|
||
directories that require more complex
|
||
or different configuration or lifetime
|
||
guarantees, please consider using
|
||
<citerefentry><refentrytitle>tmpfiles.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
</variablelist>
|
||
</refsect1>
|
||
|
||
<refsect1>
|
||
<title>Environment variables in spawned processes</title>
|
||
|
||
<para>Processes started by the system are executed in
|
||
a clean environment in which select variables
|
||
listed below are set. System processes started by systemd
|
||
do not inherit variables from PID 1, but processes
|
||
started by user systemd instances inherit all
|
||
environment variables from the user systemd instance.
|
||
</para>
|
||
|
||
<variablelist class='environment-variables'>
|
||
<varlistentry>
|
||
<term><varname>$PATH</varname></term>
|
||
|
||
<listitem><para>Colon-separated list
|
||
of directiories to use when launching
|
||
executables. Systemd uses a fixed
|
||
value of
|
||
<filename>/usr/local/sbin</filename>:<filename>/usr/local/bin</filename>:<filename>/usr/sbin</filename>:<filename>/usr/bin</filename>:<filename>/sbin</filename>:<filename>/bin</filename>.
|
||
</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>$LANG</varname></term>
|
||
|
||
<listitem><para>Locale. Can be set in
|
||
<citerefentry><refentrytitle>locale.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
|
||
or on the kernel command line (see
|
||
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
|
||
and
|
||
<citerefentry><refentrytitle>kernel-command-line</refentrytitle><manvolnum>7</manvolnum></citerefentry>).
|
||
</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>$USER</varname></term>
|
||
<term><varname>$LOGNAME</varname></term>
|
||
<term><varname>$HOME</varname></term>
|
||
<term><varname>$SHELL</varname></term>
|
||
|
||
<listitem><para>User name (twice), home
|
||
directory, and the login shell.
|
||
The variables are set for the units that
|
||
have <varname>User=</varname> set,
|
||
which includes user
|
||
<command>systemd</command> instances.
|
||
See
|
||
<citerefentry><refentrytitle>passwd</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
|
||
</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>$XDG_RUNTIME_DIR</varname></term>
|
||
|
||
<listitem><para>The directory for volatile
|
||
state. Set for the user <command>systemd</command>
|
||
instance, and also in user sessions.
|
||
See
|
||
<citerefentry><refentrytitle>pam_systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
|
||
</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>$XDG_SESSION_ID</varname></term>
|
||
<term><varname>$XDG_SEAT</varname></term>
|
||
<term><varname>$XDG_VTNR</varname></term>
|
||
|
||
<listitem><para>The identifier of the
|
||
session, the seat name, and
|
||
virtual terminal of the session. Set
|
||
by
|
||
<citerefentry><refentrytitle>pam_systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>
|
||
for login sessions.
|
||
<varname>$XDG_SEAT</varname> and
|
||
<varname>$XDG_VTNR</varname> will
|
||
only be set when attached to a seat and a
|
||
tty.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>$MAINPID</varname></term>
|
||
|
||
<listitem><para>The PID of the units
|
||
main process if it is known. This is
|
||
only set for control processes as
|
||
invoked by
|
||
<varname>ExecReload=</varname> and
|
||
similar. </para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>$MANAGERPID</varname></term>
|
||
|
||
<listitem><para>The PID of the user
|
||
<command>systemd</command> instance,
|
||
set for processes spawned by it.
|
||
</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>$LISTEN_FDS</varname></term>
|
||
<term><varname>$LISTEN_PID</varname></term>
|
||
|
||
<listitem><para>Information about file
|
||
descriptors passed to a service for
|
||
socket activation. See
|
||
<citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
|
||
</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>$TERM</varname></term>
|
||
|
||
<listitem><para>Terminal type, set
|
||
only for units connected to a terminal
|
||
(<varname>StandardInput=tty</varname>,
|
||
<varname>StandardOutput=tty</varname>,
|
||
or
|
||
<varname>StandardError=tty</varname>).
|
||
See
|
||
<citerefentry project='man-pages'><refentrytitle>termcap</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
|
||
</para></listitem>
|
||
</varlistentry>
|
||
</variablelist>
|
||
|
||
<para>Additional variables may be configured by the
|
||
following means: for processes spawned in specific
|
||
units, use the <varname>Environment=</varname> and
|
||
<varname>EnvironmentFile=</varname> options above; to
|
||
specify variables globally, use
|
||
<varname>DefaultEnvironment=</varname> (see
|
||
<citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>)
|
||
or the kernel option
|
||
<varname>systemd.setenv=</varname> (see
|
||
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>). Additional
|
||
variables may also be set through PAM,
|
||
cf. <citerefentry project='man-pages'><refentrytitle>pam_env</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
|
||
</refsect1>
|
||
|
||
<refsect1>
|
||
<title>See Also</title>
|
||
<para>
|
||
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
|
||
<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
|
||
<citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
|
||
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
|
||
<citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
|
||
<citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
|
||
<citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
|
||
<citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
|
||
<citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
|
||
<citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
|
||
<citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
|
||
<citerefentry><refentrytitle>tmpfiles.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
|
||
<citerefentry project='man-pages'><refentrytitle>exec</refentrytitle><manvolnum>3</manvolnum></citerefentry>
|
||
</para>
|
||
</refsect1>
|
||
|
||
</refentry>
|