In some cases, caching DNS results locally is not desirable, a it makes DNS
cache poisoning attacks a tad easier and also allows users on the system to
determine whether or not a particular domain got visited by another user. Thus
provide a new "Cache" resolved.conf option to disable it.
This change documents the existance of the systemd-nspawn@.service template
unit file, which was previously not mentioned at all. Since the unit file uses
slightly different default than nspawn invoked from the command line, these
defaults are now explicitly documented too.
A couple of further additions and changes are made, too.
Replaces: #3497
Add sd_notify() parameter to change watchdog_usec during runtime.
Application can change watchdog_usec value by
sd_notify like this. Example. sd_notify(0, "WATCHDOG_USEC=20000000").
To reset watchdog_usec as configured value in service file,
restart service.
Notice.
sd_event is not currently supported. If application uses
sd_event_set_watchdog, or sd_watchdog_enabled, do not use
"WATCHDOG_USEC" option through sd_notify.
The new command shows the per-link and global DNS configuration currently in
effect. This is useful to quickly see the DNS settings resolved acquired from
networkd and that was pushed into it via the bus APIs.
In makefile we create symlinks runlevel5.target to graphical.target and
runlevel2-4.target to multi-user.target. Let's say the same thing in
systemd.special manpage.
This permits services to detect whether their stdout/stderr is connected to the
journal, and if so talk to the journal directly, thus permitting carrying of
metadata.
As requested by the gtk folks: #2473
If a percentage is used, it is taken relative to the installed RAM size. This
should make it easier to write generic unit files that adapt to the local system.
This adds three new seccomp syscall groups: @keyring for kernel keyring access,
@cpu-emulation for CPU emulation features, for exampe vm86() for dosemu and
suchlike, and @debug for ptrace() and related calls.
Also, the @clock group is updated with more syscalls that alter the system
clock. capset() is added to @privileged, and pciconfig_iobase() is added to
@raw-io.
Finally, @obsolete is a cleaned up. A number of syscalls that never existed on
Linux and have no number assigned on any architecture are removed, as they only
exist in the man pages and other operating sytems, but not in code at all.
create_module() is moved from @module to @obsolete, as it is an obsolete system
call. mem_getpolicy() is removed from the @obsolete list, as it is not
obsolete, but simply a NUMA API.
This patch implements the new magic character '!'. By putting '!' in front
of a command, systemd executes it with full privileges ignoring paramters
such as User, Group, SupplementaryGroups, CapabilityBoundingSet,
AmbientCapabilities, SecureBits, SystemCallFilter, SELinuxContext,
AppArmorProfile, SmackProcessLabel, and RestrictAddressFamilies.
Fixes partially https://github.com/systemd/systemd/issues/3414
Related to https://github.com/coreos/rkt/issues/2482
Testing:
1. Create a user 'bob'
2. Create the unit file /etc/systemd/system/exec-perm.service
(You can use the example below)
3. sudo systemctl start ext-perm.service
4. Verify that the commands starting with '!' were not executed as bob,
4.1 Looking to the output of ls -l /tmp/exec-perm
4.2 Each file contains the result of the id command.
`````````````````````````````````````````````````````````````````
[Unit]
Description=ext-perm
[Service]
Type=oneshot
TimeoutStartSec=0
User=bob
ExecStartPre=!/usr/bin/sh -c "/usr/bin/rm /tmp/exec-perm*" ;
/usr/bin/sh -c "/usr/bin/id > /tmp/exec-perm-start-pre"
ExecStart=/usr/bin/sh -c "/usr/bin/id > /tmp/exec-perm-start" ;
!/usr/bin/sh -c "/usr/bin/id > /tmp/exec-perm-star-2"
ExecStartPost=/usr/bin/sh -c "/usr/bin/id > /tmp/exec-perm-start-post"
ExecReload=/usr/bin/sh -c "/usr/bin/id > /tmp/exec-perm-reload"
ExecStop=!/usr/bin/sh -c "/usr/bin/id > /tmp/exec-perm-stop"
ExecStopPost=/usr/bin/sh -c "/usr/bin/id > /tmp/exec-perm-stop-post"
[Install]
WantedBy=multi-user.target]
`````````````````````````````````````````````````````````````````
This the patch implements a notificaiton mechanism from the init process
in the container to systemd-nspawn.
The switch --notify-ready=yes configures systemd-nspawn to wait the "READY=1"
message from the init process in the container to send its own to systemd.
--notify-ready=no is equivalent to the previous behavior before this patch,
systemd-nspawn notifies systemd with a "READY=1" message when the container is
created. This notificaiton mechanism uses socket file with path relative to the contanier
"/run/systemd/nspawn/notify". The default values it --notify-ready=no.
It is also possible to configure this mechanism from the .nspawn files using
NotifyReady. This parameter takes the same options of the command line switch.
Before this patch, systemd-nspawn notifies "ready" after the inner child was created,
regardless the status of the service running inside it. Now, with --notify-ready=yes,
systemd-nspawn notifies when the service is ready. This is really useful when
there are dependencies between different contaniers.
Fixes https://github.com/systemd/systemd/issues/1369
Based on the work from https://github.com/systemd/systemd/pull/3022
Testing:
Boot a OS inside a container with systemd-nspawn.
Note: modify the commands accordingly with your filesystem.
1. Create a filesystem where you can boot an OS.
2. sudo systemd-nspawn -D ${HOME}/distros/fedora-23/ sh
2.1. Create the unit file /etc/systemd/system/sleep.service inside the container
(You can use the example below)
2.2. systemdctl enable sleep
2.3 exit
3. sudo systemd-run --service-type=notify --unit=notify-test
${HOME}/systemd/systemd-nspawn --notify-ready=yes
-D ${HOME}/distros/fedora-23/ -b
4. In a different shell run "systemctl status notify-test"
When using --notify-ready=yes the service status is "activating" for 20 seconds
before being set to "active (running)". Instead, using --notify-ready=no
the service status is marked "active (running)" quickly, without waiting for
the 20 seconds.
This patch was also test with --private-users=yes, you can test it just adding it
at the end of the command at point 3.
------ sleep.service ------
[Unit]
Description=sleep
After=network.target
[Service]
Type=oneshot
ExecStart=/bin/sleep 20
[Install]
WantedBy=multi-user.target
------------ end ------------
The long name is just too hard to type. We generally should avoid using
acronyms too liberally, if they aren't established enough, but it appears that
"RA" is known well enough. Internally we call the option "ipv6_accept_ra"
anyway, and the kernel also exposes it under this name. Hence, let's rename the
IPv6AcceptRouterAdvertisements= setting and the
[IPv6AcceptRouterAdvertisements] section to IPv6AcceptRA= and [IPv6AcceptRA].
The old setting IPv6AcceptRouterAdvertisements= is kept for compatibility with
older configuration. (However the section [IPv6AcceptRouterAdvertisements] is
not, as it was never available in a published version of systemd.
Debian and their derivatives (Ubuntu, Trisquel, etc.) use a code name
for their repositories. Thus record the code name in os-release for
processing.
Closessystemd/systemd#3429
This reworks sd-ndisc and networkd substantially to support IPv6 RA much more
comprehensively. Since the API is extended quite a bit networkd has been ported
over too, and the patch is not as straight-forward as one could wish. The
rework includes:
- Support for DNSSL, RDNSS and RA routing options in sd-ndisc and networkd. Two
new configuration options have been added to networkd to make this
configurable.
- sd-ndisc now exposes an sd_ndisc_router object that encapsulates a full RA
message, and has direct, friendly acessor functions for the singleton RA
properties, as well as an iterative interface to iterate through known and
unsupported options. The router object may either be retrieved from the wire,
or generated from raw data. In many ways the sd-ndisc API now matches the
sd-lldp API, except that no implicit database of seen data is kept. (Note
that sd-ndisc actually had a half-written, but unused implementaiton of such
a store, which is removed now.)
- sd-ndisc will now collect the reception timestamps of RA, which is useful to
make sd_ndisc_router fully descriptive of what it covers.
Fixes: #1079
New exec boolean MemoryDenyWriteExecute, when set, installs
a seccomp filter to reject mmap(2) with PAGE_WRITE|PAGE_EXEC
and mprotect(2) with PAGE_EXEC.
Recently added cgroup unified hierarchy support uses "max" in configurations
for no upper limit. While consistent with what the kernel uses for no upper
limit, it is inconsistent with what systemd uses for other controllers such as
memory or pids. There's no point in introducing another term. Update cgroup
unified hierarchy support so that "infinity" is the only term that systemd
uses for no upper limit.
Definitions of ReadWriteDirectories=, ReadOnlyDirectories=, InaccessibleDirectories=,
WorkingDirectory=, and RootDirecory= were not clear. This patch specifies when
they are relative to the host's root directory and when they are relative to the service's
root directory.
Fixes#3248
On the unified hierarchy, memory controller implements three control knobs -
low, high and max which enables more useable and versatile control over memory
usage. This patch implements support for the three control knobs.
* MemoryLow, MemoryHigh and MemoryMax are added for memory.low, memory.high and
memory.max, respectively.
* As all absolute limits on the unified hierarchy use "max" for no limit, make
memory limit parse functions accept "max" in addition to "infinity" and
document "max" for the new knobs.
* Implement compatibility translation between MemoryMax and MemoryLimit.
v2:
- Fixed missing else's in config_parse_memory_limit().
- Fixed missing newline when writing out drop-ins.
- Coding style updates to use "val > 0" instead of "val".
- Minor updates to documentation.
The sync() call on shutdown had been removed with commit 57371e5829
together with the no-sync option for the shutdown commands.
The sync call was restored in commit 4a3ad39957 but the no-sync option
wasn't re-added.
I think we should restore this option at least for the legacy halt command.
Due to the substantial interface changes in cgroup unified hierarchy, new IO
settings are introduced. Currently, IO settings apply only to unified
hierarchy and BlockIO to legacy. While the transition is necessary, it's
painful for users to have to provide configs for both. This patch implements
translation from one config set to another for configs which make sense.
* The translation takes place during application of the configs. Users won't
see IO or BlockIO settings appearing without being explicitly created.
* The translation takes place only if there is no config for the matching
cgroup hierarchy type at all.
While this doesn't provide comprehensive compatibility, it should considerably
ease transition to the new IO settings which are a superset of BlockIO
settings.
v2:
- Update test-cgroup-mask.c so that it accounts for the fact that
CGROUP_MASK_IO and CGROUP_MASK_BLKIO move together. Also, test/parent.slice
now sets IOWeight instead of BlockIOWeight.
cgroup IO controller supports maximum limits for both bandwidth and IOPS but
systemd resource control currently only supports bandwidth limits. This patch
adds support for IOReadIOPSMax and IOWriteIOPSMax when unified cgroup hierarchy
is in use.
It isn't difficult to also add BlockIOReadIOPS and BlockIOWriteIOPS for legacy
hierarchies but IO control on legacy hierarchies is half-broken anyway, so
let's leave it alone for now.
