X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=man%2Fsystemd.exec.xml;h=4294e54a5505c0a4bb339cda7123e5a9cedb41bd;hp=89e3369d3c4916b7fdce95adf31a48f906a12ef3;hb=1fda0ab5fc9cf7454c8da32941e433dc38ba9991;hpb=ab1f063390f55e14a8de87f21c4fad199eb908a6 diff --git a/man/systemd.exec.xml b/man/systemd.exec.xml index 89e3369d3..4294e54a5 100644 --- a/man/systemd.exec.xml +++ b/man/systemd.exec.xml @@ -9,16 +9,16 @@ 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 . --> @@ -44,14 +44,14 @@ systemd.exec - systemd execution environment configuration + Execution environment configuration - systemd.service, - systemd.socket, - systemd.mount, - systemd.swap + service.service, + socket.socket, + mount.mount, + swap.swap @@ -75,22 +75,26 @@ 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. Options - + WorkingDirectory= Takes an absolute directory path. Sets the working - directory for executed - processes. + 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. @@ -113,10 +117,10 @@ Group= 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. @@ -125,14 +129,19 @@ Sets the supplementary Unix groups the processes are executed - as. This takes a space separated list + 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. 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. @@ -210,13 +219,15 @@ 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 - sched_setscheduler2 - for details. + scheduling policy (see above). For + real-time scheduling policies an + integer between 1 (lowest priority) + and 99 (highest priority) can be used. + See sched_setscheduler2 + for details. + @@ -238,7 +249,13 @@ 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 sched_setaffinity2 for details. @@ -265,9 +282,29 @@ 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, however, specifier + expansion is possible. $ character has + no special meaning. + If you need to assign a value containing spaces + to a variable, use double quotes (") + for the assignment. + + Example: + Environment="VAR1=word1 word2" VAR2=word3 "VAR3=word 5 6" + gives three variables VAR1, + VAR2, VAR3. + + + + See environ7 - for details. + for details about environment variables. EnvironmentFile= @@ -275,16 +312,32 @@ Environment= but reads the environment variables from a text file. The text file should - contain new-line separated variable + 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 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 + 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 ("). + + The argument passed should be an + absolute filename 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. 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. + + The files listed with this directive will be read shortly before the process is executed. Settings from these files override settings made @@ -294,7 +347,7 @@ these files the files will be read in the order they are specified and the later setting will override the - earlier setting. + earlier setting. @@ -361,8 +414,10 @@ , , , + , + , , - or + or . If set to the file descriptor of standard input is @@ -383,11 +438,21 @@ terminal. connects standard output to the syslog3 - system logger. + system syslog + service. connects it with the kernel log buffer which is accessible via - dmesg1. - and work + dmesg1. + connects it with the journal which is + accessible via + journalctl1 + (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). , + and + work similarly but copy the output to the system console as well. connects @@ -395,8 +460,13 @@ socket activation, semantics are similar to the respective option of StandardInput=. - This setting defaults to - . + This setting defaults to the value set + with + + in + systemd-system.conf5, + which defaults to + . StandardError= @@ -410,7 +480,11 @@ the file descriptor used for standard output is duplicated for standard error. This - setting defaults to + setting defaults to the value set with + + in + systemd-system.conf5, + which defaults to . @@ -441,7 +515,7 @@ TTYVTDisallocate= - If the the terminal + If the terminal device specified with TTYPath= is a virtual console terminal try to @@ -525,7 +599,7 @@ prefixes may be disabled with SyslogLevelPrefix=, see below. For details see - sd-daemon7. + sd-daemon3. Defaults to . @@ -537,8 +611,9 @@ argument. If true and StandardOutput= or StandardError= are - set to or - log lines + set to , + or + , log lines written by the executed process that are prefixed with a log level will be passed on to syslog with this log @@ -547,7 +622,7 @@ these prefixes is disabled and the logged lines are passed on as-is. For details about this prefixing see - sd-daemon7. + sd-daemon3. Defaults to true. @@ -555,16 +630,17 @@ TimerSlackNSec= 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 prctl2 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. + integer value in nano-seconds if no + unit is specified. The usual time + units are understood + too. @@ -619,14 +695,19 @@ 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 tcpd8 - for details. + for details. Note that this option may + be used to do access control checks + only. Shell commands and commands + described in + hosts_options5 + are not supported. @@ -637,27 +718,40 @@ capability bounding set for the executed process. See capabilities7 - for details. Takes a whitespace - separated list of capability names as - read by - cap_from_name3. + for details. Takes a whitespace-separated + list of capability names as read by + cap_from_name3, + e.g. CAP_SYS_ADMIN, + CAP_DAC_OVERRIDE, + CAP_SYS_PTRACE. Capabilities listed will be included in the bounding set, all others are removed. If the list of capabilities - 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 + is prefixed with ~ + 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 or inherited capability - sets. That's what - Capabilities= is - for. If this option is not used the + permitted and inheritable capability + sets, on top of what + Capabilities= + 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. + 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 ~ (without any + further argument) the bounding set is + reset to the full set of available + capabilities, also undoing any + previous settings. @@ -670,9 +764,13 @@ , , , - and/or - . - + and/or + . 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. @@ -700,42 +798,65 @@ groups the executed processes shall be made members of. Takes a space-separated list of cgroup - identifiers. A cgroup identifier has a - format like - cpu:/foo/bar, - where "cpu" identifies the kernel + identifiers. A cgroup identifier is + formatted like + cpu:/foo/bar, + where "cpu" indicates the kernel control group controller used, and - /foo/bar is the + /foo/bar is the 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. This option is - primarily intended to place executed - processes in specific paths in - specific kernel controller - hierarchies. It is however not + path for this unit is implied. + + 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 group path in the private + systemd named hierarchy + (i.e. name=systemd), + and doing this might result in + undefined behaviour. For details about control groups see cgroups.txt. + url="http://www.kernel.org/doc/Documentation/cgroups/cgroups.txt">cgroups.txt. + + 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. + + Note that the list of control + group assignments of a unit is + extended implicitly based on the + settings of + DefaultControllers= + of + systemd-system.conf5, + but a unit's + ControlGroup= + setting for a specific controller + takes precedence. @@ -750,12 +871,27 @@ the group. + + ControlGroupPersistent= + 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 PaxControlGroups. + + ControlGroupAttribute= Set a specific control group attribute for executed - processes, and (if needed) add the the + processes, and (if needed) add the executed processes to a cgroup in the hierarchy of the controller the attribute belongs to. Takes two @@ -778,8 +914,8 @@ the controller and the default unit cgroup path is implied. Thus, using ControlGroupAttribute= - is in most case sufficient to make use - of control group enforcements, + is in most cases sufficient to make + use of control group enforcements, explicit ControlGroup= are only necessary in case the implied @@ -790,18 +926,36 @@ url="http://www.kernel.org/doc/Documentation/cgroups/cgroups.txt">cgroups.txt. This option may appear more than once, in order to set multiple control group - attributes. + 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 + CPUShares=, + MemoryLimit=, + MemorySoftLimit, + DeviceAllow=, + DeviceDeny=, + BlockIOWeight=, + BlockIOReadBandwidth=, + BlockIOWriteBandwidth=. + CPUShares= Assign the specified - overall CPU time shares to the processes executed. Takes - an integer value. This controls the + overall CPU time shares to the + processes executed. Takes an integer + value. This controls the cpu.shares control - group attribute. For details about - this control group attribute see sched-design-CFS.txt. @@ -814,9 +968,9 @@ 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 - resp. Terabytes (to the base - 1024). This controls the + as Kilobytes, Megabytes, Gigabytes, + or Terabytes (to the base + 1024), respectively. This controls the memory.limit_in_bytes and memory.soft_limit_in_bytes @@ -832,13 +986,13 @@ Control access to specific device nodes by the executed processes. Takes two - space separated strings: a device node + space-separated strings: a device node path (such as /dev/null) followed by a combination of r, w, m - to control reading, writing resp. + to control reading, writing, or creating of the specific device node - by the unit. This controls the + by the unit, respectively. This controls the devices.allow and devices.deny @@ -848,16 +1002,77 @@ url="http://www.kernel.org/doc/Documentation/cgroups/devices.txt">devices.txt. + + BlockIOWeight= + + 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 + blkio.weight and + blkio.weight_device + 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 + blkio-controller.txt. + + + + BlockIOReadBandwidth= + BlockIOWriteBandwidth= + + 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 + blkio.read_bps_device + and + blkio.write_bps_device + control group attributes. Use this + option multiple times to set bandwidth + limits for multiple devices. For + details about these control group + attributes see blkio-controller.txt. + + ReadWriteDirectories= ReadOnlyDirectories= InaccessibleDirectories= Sets up a new - file-system name space for executed + file system namespace for executed processes. These options may be used to limit access a process might have - to the main file-system + to the main file system hierarchy. Each setting takes a space-separated list of absolute directory paths. Directories listed in @@ -871,18 +1086,21 @@ usual file access controls would permit this. Directories listed in InaccessibleDirectories= - 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. + 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. @@ -891,16 +1109,20 @@ Takes a boolean argument. If true sets up a new file system namespace for the executed - processes and mounts a private - /tmp directory - inside it, that is not shared by + processes and mounts private + /tmp and + /var/tmp 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 - /tmp - impossible. Defaults to + /tmp or + /var/tmp + impossible. All temporary data created + by service will be removed after service + is stopped. Defaults to false. @@ -929,26 +1151,19 @@ , or , which - control whether namespaces set up with - ReadWriteDirectories=, - ReadOnlyDirectories= - and - InaccessibleDirectories= - receive or propagate new mounts - from/to the main namespace. See - mount1 - for details. Defaults to - , i.e. the new - namespace will both receive new mount - points from the main namespace as well - as propagate new mounts to - it. + control whether the file system + namespace set up for this unit's + processes will receive or propagate + new mounts. See + mount2 + for details. Default to + . UtmpIdentifier= - Takes a a four + Takes a four character identifier string for an utmp/wtmp entry for this service. This should only be set for services such @@ -966,6 +1181,71 @@ this service. + + IgnoreSIGPIPE= + + Takes a boolean + argument. If true, causes SIGPIPE to be + ignored in the executed + process. Defaults to true because + SIGPIPE generally is useful only in + shell pipelines. + + + + NoNewPrivileges= + + 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. + + + + SystemCallFilter= + + 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 ~ + the effect is inverted: only the + listed system calls will result in + immediate process termination + (blacklisting). If this option is used + NoNewPrivileges=yes + 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 + execve, + rt_sigreturn, + sigreturn, + exit_group, + exit 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. + + @@ -974,11 +1254,14 @@ systemd1, systemctl8, + journalctl8, systemd.unit5, systemd.service5, systemd.socket5, systemd.swap5, - systemd.mount5 + systemd.mount5, + systemd.kill5, + systemd.directives7