Copyright 2010 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ 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
- General Public License for more details.
+ Lesser General Public License for more details.
- You should have received a copy of the GNU General Public License
+ You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
-->
<refnamediv>
<refname>systemd.exec</refname>
- <refpurpose>systemd execution environment configuration</refpurpose>
+ <refpurpose>Execution environment configuration</refpurpose>
</refnamediv>
<refsynopsisdiv>
- <para><filename>systemd.service</filename>,
- <filename>systemd.socket</filename>,
- <filename>systemd.mount</filename>,
- <filename>systemd.swap</filename></para>
+ <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>
for more information on the specific unit
configuration files. The execution specific
configuration options are configured in the [Service],
- [Socket], [Mount] resp. [Swap] section, depending on the unit
+ [Socket], [Mount], or [Swap] sections, depending on the unit
type.</para>
</refsect1>
<refsect1>
<title>Options</title>
- <variablelist>
+ <variablelist class='unit-directives'>
<varlistentry>
<term><varname>WorkingDirectory=</varname></term>
<listitem><para>Takes an absolute
directory path. Sets the working
- directory for executed
- processes.</para></listitem>
+ 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>Group=</varname></term>
<listitem><para>Sets the Unix user
- resp. group the processes are executed
- as. Takes a single user resp. group
+ 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
+ set, the default group of the user is
chosen.</para></listitem>
</varlistentry>
of group names or IDs. This option may
be specified more than once in which
case all listed groups are set as
- supplementary groups. This option does
- not override but extends the list of
- supplementary groups configured in the
- system group database for the
+ 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>
<listitem><para>Sets the CPU
scheduling priority for executed
- processes. Takes an integer between 1
- (lowest priority) and 99 (highest
- priority). The available priority
+ processes. The available priority
range depends on the selected CPU
- scheduling policy (see above). See
- <citerefentry><refentrytitle>sched_setscheduler</refentrytitle><manvolnum>2</manvolnum></citerefentry>
- for details.</para></listitem>
+ 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>
<listitem><para>Controls the CPU
affinity of the executed
processes. Takes a space-separated
- list of CPU indexes. See
+ list of CPU indexes. 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>
octal notation. See
<citerefentry><refentrytitle>umask</refentrytitle><manvolnum>2</manvolnum></citerefentry>
for details. Defaults to
- 0002.</para></listitem>
+ 0022.</para></listitem>
</varlistentry>
<varlistentry>
in which case all listed variables
will be set. If the same variable is
set twice the later setting will
- override the earlier setting. See
+ 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, and $ 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>.
+ </para>
+
+ <para>
+ See
<citerefentry><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry>
- for details.</para></listitem>
+ for details about environment variables.</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>EnvironmentFile=</varname></term>
contain new-line separated variable
assignments. Empty lines and lines
starting with ; or # will be ignored,
- which may be used for commenting. The
- argument passed should be an absolute
- file name, optionally prefixed with
+ 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 file name or wildcard
+ expression, optionally prefixed with
"-", which indicates that if the file
does not exist it won't be read and no
- error or warning message is
- logged. The files listed with this
+ 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. Settings from
these files override settings made
these files the files will be read in
the order they are specified and the
later setting will override the
- earlier setting. </para></listitem>
+ earlier setting.</para></listitem>
</varlistentry>
<varlistentry>
<option>tty</option>,
<option>syslog</option>,
<option>kmsg</option>,
+ <option>journal</option>,
+ <option>syslog+console</option>,
<option>kmsg+console</option>,
- <option>syslog+console</option> or
+ <option>journal+console</option> or
<option>socket</option>. If set to
<option>inherit</option> the file
descriptor of standard input is
terminal. <option>syslog</option>
connects standard output to the
<citerefentry><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>
- system logger. <option>kmsg</option>
+ system syslog
+ service. <option>kmsg</option>
connects it with the kernel log buffer
which is accessible via
- <citerefentry><refentrytitle>dmesg</refentrytitle><manvolnum>1</manvolnum></citerefentry>. <option>syslog+console</option>
- and <option>kmsg+console</option> work
+ <citerefentry><refentrytitle>dmesg</refentrytitle><manvolnum>1</manvolnum></citerefentry>. <option>journal</option>
+ connects it 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 is implicitly stored
+ in the journal as well, those options
+ are hence supersets of this
+ one). <option>syslog+console</option>,
+ <option>journal+console</option> and
+ <option>kmsg+console</option> work
similarly but copy the output to the
system console as
well. <option>socket</option> connects
socket activation, semantics are
similar to the respective option of
<varname>StandardInput=</varname>.
- This setting defaults to
- <option>inherit</option>.</para></listitem>
+ 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>
<option>inherit</option> the file
descriptor used for standard output is
duplicated for standard error. This
- setting defaults to
+ 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>
</varlistentry>
<varlistentry>
<term><varname>TTYVTDisallocate=</varname></term>
- <listitem><para>If the the terminal
+ <listitem><para>If the terminal
device specified with
<varname>TTYPath=</varname> is a
virtual console terminal try to
prefixes may be disabled with
<varname>SyslogLevelPrefix=</varname>,
see below. For details see
- <citerefentry><refentrytitle>sd-daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>.
+ <citerefentry><refentrytitle>sd-daemon</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
Defaults to
<option>info</option>.</para></listitem>
argument. If true and
<varname>StandardOutput=</varname> or
<varname>StandardError=</varname> are
- set to <option>syslog</option> or
- <option>kmsg</option> log lines
+ 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
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>7</manvolnum></citerefentry>.
+ <citerefentry><refentrytitle>sd-daemon</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
Defaults to true.</para></listitem>
</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
+ 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 and does
- not understand any other
- units.</para></listitem>
+ integer value in nano-seconds if no
+ unit is specified. The usual time
+ units are understood
+ too.</para></listitem>
</varlistentry>
<varlistentry>
conjunction with socket-activated
services, and stream sockets (TCP) in
particular. It has no effect on other
- socket types (e.g. datagram/UDP) and on processes
- unrelated to socket-based
+ socket types (e.g. datagram/UDP) and
+ on processes unrelated to socket-based
activation. If the tcpwrap
verification fails daemon start-up
will fail and the connection is
terminated. See
<citerefentry><refentrytitle>tcpd</refentrytitle><manvolnum>8</manvolnum></citerefentry>
- for details.</para></listitem>
+ for details. Note that this option may
+ be used to do access control checks
+ only. Shell commands and commands
+ described in
+ <citerefentry><refentrytitle>hosts_options</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+ are not supported.</para></listitem>
</varlistentry>
<varlistentry>
is prefixed with ~ all but the listed
capabilities will be included, the
effect of the assignment
- inverted. Note that this option does
- not actually set or unset any
- capabilities in the effective,
- permitted or inherited capability
- sets. That's what
- <varname>Capabilities=</varname> is
- for. If this option is not used the
+ inverted. Note that this option also
+ effects 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.</para></listitem>
+ 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, and all prior
+ settings have no
+ effect.</para></listitem>
</varlistentry>
<varlistentry>
<option>keep-caps-locked</option>,
<option>no-setuid-fixup</option>,
<option>no-setuid-fixup-locked</option>,
- <option>no-setuid-noroot</option> and/or
- <option>no-setuid-noroot-locked</option>.
- </para></listitem>
+ <option>noroot</option> and/or
+ <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.</para></listitem>
</varlistentry>
<varlistentry>
groups the executed processes shall be
made members of. Takes a
space-separated list of cgroup
- identifiers. A cgroup identifier has a
- format like
+ identifiers. A cgroup identifier is
+ formatted like
<filename>cpu:/foo/bar</filename>,
- where "cpu" identifies the kernel
+ where "cpu" indicates the kernel
control group controller used, and
<filename>/foo/bar</filename> is the
- control group path. The controller name
- and ":" may be omitted in which case
- the named systemd control group
+ control group path. The controller
+ name and ":" may be omitted in which
+ case the named systemd control group
hierarchy is implied. Alternatively,
the path and ":" may be omitted, in
which case the default control group
- path for this unit is implied. This
- option may be used to place executed
- processes in arbitrary groups in
- arbitrary hierarchies -- which can be
- configured externally with additional execution limits. By default
- systemd will place all executed
- processes in separate per-unit control
- groups (named after the unit) in the
- systemd named hierarchy. Since every
- process can be in one group per
- hierarchy only overriding the control group
- path in the named systemd hierarchy
- will disable automatic placement in
- the default group. For details about control
- groups see <ulink
- url="http://www.kernel.org/doc/Documentation/cgroups/cgroups.txt">cgroups.txt</ulink>.</para></listitem>
+ path for this unit is implied.</para>
+
+ <para>This option may be used to place
+ executed processes in arbitrary groups
+ in arbitrary hierarchies -- which may
+ then be externally configured with
+ additional execution limits. By
+ default systemd will place all
+ executed processes in separate
+ per-unit control groups (named after
+ the unit) in the systemd named
+ hierarchy. This option is primarily
+ intended to place executed processes
+ in specific paths in specific kernel
+ controller hierarchies. It is not
+ recommended to manipulate the service
+ control group path in the systemd
+ named hierarchy. For details about
+ control groups see <ulink
+ url="http://www.kernel.org/doc/Documentation/cgroups/cgroups.txt">cgroups.txt</ulink>.</para>
+
+ <para>This option may appear more than
+ once, in which case the list of
+ control group assignments is
+ merged. If the same hierarchy gets two
+ different paths assigned only the
+ later setting will take effect. If the
+ empty string is assigned to this
+ option the list of control group
+ assignments is reset, all previous
+ assignments will have no
+ effect.</para>
+
+ <para>Note that the list of control
+ group assignments of a unit is
+ extended implicitly based on the
+ settings of
+ <varname>DefaultControllers=</varname>
+ of
+ <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ but a unit's
+ <varname>ControlGroup=</varname>
+ setting for a specific controller
+ takes precedence.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>ControlGroupModify=</varname></term>
+ <listitem><para>Takes a boolean
+ argument. If true, the control groups
+ created for this unit will be owned by
+ the user specified with
+ <varname>User=</varname> (and the
+ appropriate group), and he/she can create
+ subgroups as well as add processes to
+ the group.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>ControlGroupPersistent=</varname></term>
+ <listitem><para>Takes a boolean
+ argument. If true, the control groups
+ created for this unit will be marked
+ to be persistent, i.e. systemd will
+ not remove them when stopping the
+ unit. The default is false, meaning
+ that the control groups will be
+ removed when the unit is stopped. For
+ details about the semantics of this
+ logic see <ulink
+ url="http://www.freedesktop.org/wiki/Software/systemd/PaxControlGroups">PaxControlGroups</ulink>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>ControlGroupAttribute=</varname></term>
+
+ <listitem><para>Set a specific control
+ group attribute for executed
+ processes, and (if needed) add the
+ executed processes to a cgroup in the
+ hierarchy of the controller the
+ attribute belongs to. Takes two
+ space-separated arguments: the
+ attribute name (syntax is
+ <literal>cpu.shares</literal> where
+ <literal>cpu</literal> refers to a
+ specific controller and
+ <literal>shares</literal> to the
+ attribute name), and the attribute
+ value. Example:
+ <literal>ControlGroupAttribute=cpu.shares
+ 512</literal>. If this option is used
+ for an attribute that belongs to a
+ kernel controller hierarchy the unit
+ is not already configured to be added
+ to (for example via the
+ <literal>ControlGroup=</literal>
+ option) then the unit will be added to
+ the controller and the default unit
+ cgroup path is implied. Thus, using
+ <varname>ControlGroupAttribute=</varname>
+ is in most cases sufficient to make
+ use of control group enforcements,
+ explicit
+ <varname>ControlGroup=</varname> are
+ only necessary in case the implied
+ default control group path for a
+ service is not desirable. For details
+ about control group attributes see
+ <ulink
+ url="http://www.kernel.org/doc/Documentation/cgroups/cgroups.txt">cgroups.txt</ulink>. This
+ option may appear more than once, in
+ order to set multiple control group
+ attributes. If this option is used
+ multiple times for the same cgroup
+ attribute only the later setting takes
+ effect. If the empty string is
+ assigned to this option the list of
+ attributes is reset, all previous
+ cgroup attribute settings have no
+ effect, including those done with
+ <varname>CPUShares=</varname>,
+ <varname>MemoryLimit=</varname>,
+ <varname>MemorySoftLimit</varname>,
+ <varname>DeviceAllow=</varname>,
+ <varname>DeviceDeny=</varname>,
+ <varname>BlockIOWeight=</varname>,
+ <varname>BlockIOReadBandwidth=</varname>,
+ <varname>BlockIOWriteBandwidth=</varname>.
+ </para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>CPUShares=</varname></term>
+
+ <listitem><para>Assign the specified
+ overall CPU time shares to the
+ processes executed. Takes an integer
+ value. This controls the
+ <literal>cpu.shares</literal> control
+ group attribute, which defaults to
+ 1024. For details about this control
+ group attribute see <ulink
+ url="http://www.kernel.org/doc/Documentation/scheduler/sched-design-CFS.txt">sched-design-CFS.txt</ulink>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>MemoryLimit=</varname></term>
+ <term><varname>MemorySoftLimit=</varname></term>
+
+ <listitem><para>Limit the overall memory usage
+ of the executed processes to a certain
+ size. Takes a memory size in bytes. If
+ the value is suffixed with K, M, G or
+ T the specified memory size is parsed
+ as Kilobytes, Megabytes, Gigabytes,
+ or Terabytes (to the base
+ 1024), respectively. This controls the
+ <literal>memory.limit_in_bytes</literal>
+ and
+ <literal>memory.soft_limit_in_bytes</literal>
+ control group attributes. For details
+ about these control group attributes
+ see <ulink
+ url="http://www.kernel.org/doc/Documentation/cgroups/memory.txt">memory.txt</ulink>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>DeviceAllow=</varname></term>
+ <term><varname>DeviceDeny=</varname></term>
+
+ <listitem><para>Control access to
+ specific device nodes by the executed processes. Takes two
+ space separated strings: a device node
+ path (such as
+ <filename>/dev/null</filename>)
+ followed by a combination of r, w, m
+ to control reading, writing, or
+ creating of the specific device node
+ by the unit, respectively. This controls the
+ <literal>devices.allow</literal>
+ and
+ <literal>devices.deny</literal>
+ control group attributes. For details
+ about these control group attributes
+ see <ulink
+ url="http://www.kernel.org/doc/Documentation/cgroups/devices.txt">devices.txt</ulink>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>BlockIOWeight=</varname></term>
+
+ <listitem><para>Set the default or
+ per-device overall block IO weight
+ value for the executed
+ processes. Takes either a single
+ weight value (between 10 and 1000) to
+ set the default block IO weight, or a
+ space separated pair of a file path
+ and a weight value to specify the
+ device specific weight value (Example:
+ "/dev/sda 500"). The file path may be
+ specified as path to a block device
+ node or as any other file in which
+ case the backing block device of the
+ file system of the file is
+ determined. This controls the
+ <literal>blkio.weight</literal> and
+ <literal>blkio.weight_device</literal>
+ control group attributes, which
+ default to 1000. Use this option
+ multiple times to set weights for
+ multiple devices. For details about
+ these control group attributes see
+ <ulink
+ url="http://www.kernel.org/doc/Documentation/cgroups/blkio-controller.txt">blkio-controller.txt</ulink>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>BlockIOReadBandwidth=</varname></term>
+ <term><varname>BlockIOWriteBandwidth=</varname></term>
+
+ <listitem><para>Set the per-device
+ overall block IO bandwidth limit for
+ the executed processes. Takes a space
+ separated pair of a file path and a
+ bandwidth value (in bytes per second)
+ to specify the device specific
+ bandwidth. The file path may be
+ specified as path to a block device
+ node or as any other file in which
+ case the backing block device of the
+ file system of the file is determined.
+ If the bandwidth is suffixed with K, M,
+ G, or T the specified bandwidth is
+ parsed as Kilobytes, Megabytes,
+ Gigabytes, or Terabytes, respectively (Example:
+ "/dev/disk/by-path/pci-0000:00:1f.2-scsi-0:0:0:0
+ 5M"). This controls the
+ <literal>blkio.read_bps_device</literal>
+ and
+ <literal>blkio.write_bps_device</literal>
+ control group attributes. Use this
+ option multiple times to set bandwidth
+ limits for multiple devices. For
+ details about these control group
+ attributes see <ulink
+ url="http://www.kernel.org/doc/Documentation/cgroups/blkio-controller.txt">blkio-controller.txt</ulink>.</para></listitem>
</varlistentry>
<varlistentry>
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. You must list submounts
- separately in these settings to
- ensure the same limited access. These
- options may be specified more than
- once in which case all directories
- listed will have limited access from
- within the
- namespace.</para></listitem>
+ will be made inaccessible for
+ processes inside the namespace. Note
+ that restricting access with these
+ options does not extend to submounts
+ of a directory. You must list
+ submounts separately in these settings
+ to ensure the same limited
+ access. 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></listitem>
</varlistentry>
<varlistentry>
<term><varname>PrivateTmp=</varname></term>
<listitem><para>Takes a boolean
- argument. If true sets up a new
- namespace for the executed processes
- and mounts a private
- <filename>/tmp</filename> directory
- inside it, that is not shared by
+ 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 are 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>
- impossible. Defaults to false.</para></listitem>
+ <filename>/tmp</filename> or
+ <filename>/var/tmp</filename>
+ impossible. All temporary data created
+ by service will be removed after service
+ is stopped. Defaults to
+ false.</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.</para></listitem>
</varlistentry>
<varlistentry>
<option>shared</option>,
<option>slave</option> or
<option>private</option>, which
- control whether namespaces set up with
- <varname>ReadWriteDirectories=</varname>,
- <varname>ReadOnlyDirectories=</varname>
- and
- <varname>InaccessibleDirectories=</varname>
- receive or propagate new mounts
- from/to the main namespace. See
- <citerefentry><refentrytitle>mount</refentrytitle><manvolnum>1</manvolnum></citerefentry>
- for details. Defaults to
- <option>shared</option>, i.e. the new
- namespace will both receive new mount
- points from the main namespace as well
- as propagate new mounts to
- it.</para></listitem>
+ control whether the file system
+ namespace set up for this unit's
+ processes will receive or propagate
+ new mounts. See
+ <citerefentry><refentrytitle>mount</refentrytitle><manvolnum>2</manvolnum></citerefentry>
+ for details. Default to
+ <option>shared</option>.</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>UtmpIdentifier=</varname></term>
- <listitem><para>Takes a a four
+ <listitem><para>Takes a four
character identifier string for an
utmp/wtmp entry for this service. This
should only be set for services such
this service.</para></listitem>
</varlistentry>
+ <varlistentry>
+ <term><varname>IgnoreSIGPIPE=</varname></term>
+
+ <listitem><para>Takes a boolean
+ argument. If true causes SIGPIPE to be
+ ignored in the executed
+ process. Defaults to true, since
+ SIGPIPE 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
+ process except for the listed ones
+ will result in immediate process
+ termination with the SIGSYS 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 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 don't
+ 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></listitem>
+ </varlistentry>
+
</variablelist>
</refsect1>
<para>
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</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.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>
</para>
</refsect1>
~ianmdlvl / elogind.git / blobdiff