Commit Graph
306 Commits
Author SHA1 Message Date
Zbigniew Jędrzejewski-Szmek e019ea738d pid1: order units using TTYVHangup= after vconsole setup
The goal of this change is to delay getty services until after
systemd-vconsole-setup has finished. systemd-vconsole-setup starts loadkeys,
and it seems that when loadkeys is interrupted by the TTY hangup call we do
when starting tty services [1], so that loadkeys starts getting EIO from the
ioctl("/dev/tty1", KDSKBENT) syscall it does.

Fixes #26908.

[1] https://github.com/legionus/kbd/issues/92#issuecomment-1554451788

Initially I wanted to add ordering dependencies to individual units, but
TTYVHangup= can be added to other various external units too. The solution with
an implicit dependency should cover those cases too.
2023-05-19 17:46:30 +02:00
Lennart Poettering 4fb8f1e883 service: allow freeing the fdstore via cleaning
Now that we have a potentially pinned fdstore let's add a concept for
cleaning it explicitly on user requested. Let's expose this via
"systemctl clean", i.e. the same way as user directories are cleaned.
2023-04-13 06:44:27 +02:00
Lennart Poettering 84be0c710d tree-wide: hook up image dissection policy logic everywhere 2023-04-05 20:45:30 +02:00
Daan De Meyer 1522077269 core: Move DynamicCreds into ExecRuntime
This is just another piece of runtime data so let's store it in
ExecRuntime alongside the other runtime data.
2023-03-27 14:47:30 +02:00
Daan De Meyer 28135da3cd core: Introduce unit private exec runtime
Currently, exec runtimes can be shared between units (using
JoinsNamespaceOf=). Let's introduce a concept of a private exec
runtime that isn't shared with JoinsNamespaceOf=. The existing
ExecRuntime struct is renamed to ExecRuntimeShared and becomes a
private member of the new private ExecRuntime.
2023-03-27 14:46:57 +02:00
Daan De Meyer e52a696a9a execute: Do not pass destroy as a boolean argument to unref()
Let's mimick what we do for DynamicUser and have two separate functions
for unreffing and destroying a ExecSharedRuntime object.
2023-03-27 14:32:58 +02:00
Daan De Meyer e76506b748 execute: Rename ExecRuntime to ExecSharedRuntime
Preparation for next commit
2023-03-27 14:05:30 +02:00
Lennart Poettering 50a4217bbe core: move encrypted credential check to execute.c
This is an operation on an ExecContext, hence it probably should be
placed there.
2023-03-23 18:22:27 +01:00
Lennart Poettering 874cdcbcf5 core: rename "mount_flags" → "mount_propagation_flag" internally where appropriate
ExecContext has a field that controls the mount propagation flag of the
mounts in the resulting namespace. This is exposed as "MountFlags="
which is super confusing, as it suggests one could control more than
propagation, and that it was actually a flags field. It's an enum
though only, and nothing else.

We might want to rename this externally one day, but given the compat
kludges this requires and the fact this is somewhat nichey it might not
be worth it. But internally let's rename it, as it makes things much
easier to grok, in particular as part of the codebase already exposed
the concept as mount_propagation_flag.

No actual code flow changes, just some renaming.
2023-03-14 13:00:27 +09:00
Lennart Poettering 6bb0084204 pid1: add unit file settings to control memory pressure logic 2023-03-01 09:43:23 +01:00
Yu Watanabe 2400212128 core/execute: make PrivateMounts= tristate
No functional change, just preparation for later commits.
2023-02-23 15:09:13 +09:00
Yu Watanabe fbbb9697b6 core/execute: introduce exec_needs_network_namespace() helper function 2023-02-23 15:09:13 +09:00
Michal Koutný b9f976fb45 core: mount namespaces: Remove auxiliary bind mounts directory after unit termination
Unit that requires its own mount namespace creates a temporary directory
to implement dynamic bind mounts (org.freedesktop.systemd1.Manager.BindMountUnit).
However, this directory is never removed and they will accumulate for
each unique unit (e.g. templated units of systemd-coredump@).

Attach the auxiliary runtime directory existence to lifetime of other
"runtime" only per-unit directories.
2023-01-19 21:58:10 +01:00
Richard Phibel cd48e23f6a core: add OpenFile setting 2023-01-10 15:16:26 +01:00
Quentin Deslandes 523ea1237a journal: log filtering options support in PID1
Define new unit parameter (LogFilterPatterns) to filter logs processed by
journald.

This option is used to store a regular expression which is carried from
PID1 to systemd-journald through a cgroup xattrs:
`user.journald_log_filter_patterns`.
2022-12-15 09:57:39 +00:00
Yu Watanabe a2ab603cc4 core: do not create symlink to private directory if parent already exists
The very basic functinality of StateDirectory= or friends is creating
specified directories. That should work if one entry is a subdirectory
of another. However, it does not when combined with DynamicUser=yes.

To support such case, this adds ExecDirectoryItem.only_create flag, and
if it is set PID1 only create private directory, and not create the symlink
to the private directory.

Fixes #24783.
2022-10-03 09:25:00 +09:00
Yu Watanabe 564e5c9878 core: make exec_directory_add() extends existing symlinks
Follow-up for 211a3d87fb.

Previously, although ExecDirectoryItem.symlinks is strv, it always
contains at most one symlink.
2022-10-03 09:25:00 +09:00
Yu Watanabe b48ed70c79 Revert NFTSet feature
This reverts PR #22587 and its follow-up commit. More specifically,
2299b1cae3 (partially),
e176f855278d5098d3fecc5aa24ba702147d42e0,
ceb46a31a01b3d3d1d6095d857e29ea214a2776b, and
51bb9076ab8c050bebb64db5035852385accda35.

The PR was merged without final approval, and has several issues:
- OSS fuzz reported issues in the conf parser,
- It calls synchrnous netlink call, it should not be especially in PID1,
- The importance of NFTSet for CGroup and DynamicUser may be
  questionable, at least, there was no justification PID1 should support
  it.
- For networkd, it should be implemented with Request object,
- There is no test for the feature.

Fixes #23711.
Fixes #23717.
Fixes #23719.
Fixes #23720.
Fixes #23721.
Fixes #23759.
2022-06-22 22:23:58 +09:00
Topi Miettinen 46c3b1ff88 core: firewall integration with DynamicUserNFTSet=
New directive `DynamicUserNFTSet=` provides a method for integrating
configuration of dynamic users into firewall rules with NFT sets.

Example:
```
table inet filter {
        set u {
                typeof meta skuid
        }

        chain service_output {
                meta skuid != @u drop
                accept
        }
}
```

```
/etc/systemd/system/dunft.service
[Service]
DynamicUser=yes
DynamicUserNFTSet=inet:filter:u
ExecStart=/bin/sleep 1000

[Install]
WantedBy=multi-user.target
```

```
$ sudo nft list set inet filter u
table inet filter {
        set u {
                typeof meta skuid
                elements = { 64864 }
        }
}
$ ps -n --format user,group,pid,command -p `pgrep sleep`
    USER    GROUP     PID COMMAND
   64864    64864   55158 /bin/sleep 1000
```
2022-06-08 16:12:25 +00:00
Lennart Poettering 2ad591a3a3 pid1: search for creds in LoadCredential=/LoadCredentialEncrypted=
This adds support for searching for credentials more comprehensively.

Specifically, unless an absolute source path is specified we'll now
search for the credentials in the system credentials first, and then in
/etc/credstore/, /run/credstore/, and /usr/lib/credstore, making these
dirs hence the recommended place for credentials to leave in the system.

For LoadCredentialEncrypted= we'll also look into
/etc/credstore.encrypted/, /run/credstore.encrypted/, …. These dirs are
hence suitable for credentials whose provenience isn't trusted (e.g.
UEFI creds from systemd-stub), and thus require to be authenticated
before use.
2022-04-28 18:12:00 +02:00
Lennart PoetteringandLukas Märdian de90700f36 pid1: set SYSTEMD_NSS_DYNAMIC_BYPASS=1 env var for dbus-daemon
There's currently a deadlock between PID 1 and dbus-daemon: in some
cases dbus-daemon will do NSS lookups (which are blocking) at the same
time PID 1 synchronously blocks on some call to dbus-daemon. Let's break
that by setting SYSTEMD_NSS_DYNAMIC_BYPASS=1 env var for dbus-daemon,
which will disable synchronously blocking varlink calls from nss-systemd
to PID 1.

In the long run we should fix this differently: remove all synchronous
calls to dbus-daemon from PID 1. This is not trivial however: so far we
had the rule that synchronous calls from PID 1 to the dbus broker are OK
as long as they only go to interfaces implemented by the broke itself
rather than services reachable through it. Given that the relationship
between PID 1 and dbus is kinda special anyway, this was considered
acceptable for the sake of simplicity, since we quite often need
metadata about bus peers from the broker, and the asynchronous logic
would substantially complicate even the simplest method handlers.

This mostly reworks the existing code that sets SYSTEMD_NSS_BYPASS_BUS=
(which is a similar hack to deal with deadlocks between nss-systemd and
dbus-daemon itself) to set SYSTEMD_NSS_DYNAMIC_BYPASS=1 instead. No code
was checking SYSTEMD_NSS_BYPASS_BUS= anymore anyway, and it used to
solve a similar problem, hence it's an obvious piece of code to rework
like this.

Issue originally tracked down by Lukas Märdian. This patch is inspired
and closely based on his patch:

       https://github.com/systemd/systemd/pull/22038

Fixes: #15316
Co-authored-by: Lukas Märdian <slyon@ubuntu.com>
2022-02-18 10:49:36 +01:00
Luca Boccassi a07b992606 core: add ExtensionDirectories= setting
Add a new setting that follows the same principle and implementation
as ExtensionImages, but using directories as sources.
It will be used to implement support for extending portable images
with directories, since portable services can already use a directory
as root.
2022-01-21 22:53:12 +09:00
Peter Morrow cdebedb4d4 service: pass service exit status to spawned On{Failure,Success}= dependency
When a service exits and triggers either an OnFailure= or OnSuccess=
dependency we now set a new environment variable for the ExecStart= and
ExecStartPre= process. This variable $MONITOR_METADATA exposes the
metadata relating to the service which triggered the dependency.
MONITOR_METADATA takes the following form:

MONITOR_METADATA="SERVICE_RESULT=<result-string0>,EXIT_CODE=<exit-code0>,EXIT_STATUS=<exit-status0>,INVOCATION_ID=<id>,UNIT=<triggering-unit0.service>;SERVICE_RESULT=<result-stringN>,EXIT_CODE=<exit-codeN>,=EXIT_STATUS=<exit-statusN>,INVOCATION_ID=<id>,UNIT=<triggering-unitN.service>"

MONITOR_METADATA is space separated set of metadata relating to the
service(s) which triggered the dependency. This is a list since if we
have 2 services which trigger the same dependency then the dependency
start job may be merged. In this case we need to pass both service
metadata to the triggered service. If there is no job merging then
MONITOR_METADATA will be a single entry.

For example, in the case we had a service "failer.service" which
triggers "failer-handler.service", the following variable is exported to
the ExecStart= and ExecStartPre= processes in failer-handler.service:

MONITOR_METADATA="SERVICE_RESULT=exit-code,EXIT_CODE=exited,EXIT_STATUS=1,INVOCATION_ID=67c657ed7b34466ea369abdf994c6393,UNIT=failer.service"

In another example where we have failer.service and failer2.service
which both also trigger failer-handler.service then the start job for
failer-handler.service may be merged and we might get the following:

MONITOR_METADATA="SERVICE_RESULT=exit-code,EXIT_CODE=exited,EXIT_STATUS=1,INVOCATION_ID=16a93ad196c94109990fb8b9aa5eef5f,UNIT=failer.service;SERVICE_RESULT=exit-code,EXIT_CODE=exited,EXIT_STATUS=1,INVOCATION_ID=ff70131e4cc145e994fb621de25a3e8f,UNIT=failer2.service"
2021-12-13 11:25:57 +00:00
Daan De Meyer 51462135fb exec: Add TTYRows and TTYColumns properties to set TTY dimensions 2021-11-05 21:32:14 +00:00
Luca Boccassi 211a3d87fb core: add [State|Runtime|Cache|Logs]Directory symlink as second parameter
When combined with a tmpfs on /run or /var/lib, allows to create
arbitrary and ephemeral symlinks for StateDirectory or RuntimeDirectory.
This is especially useful when sharing these directories between
different services, to make the same state/runtime directory 'backend'
appear as different names to each service, so that they can be added/removed
to a sharing agreement transparently, without code changes.

An example (simplified, but real) use case:

foo.service:
StateDirectory=foo

bar.service:
StateDirectory=bar

foo.service.d/shared.conf:
StateDirectory=
StateDirectory=shared:foo

bar.service.d/shared.conf:
StateDirectory=
StateDirectory=shared:bar

foo and bar use respectively /var/lib/foo and /var/lib/bar. Then
the orchestration layer decides to stop this sharing, the drop-in
can be removed. The services won't need any update and will keep
working and being able to store state, transparently.

To keep backward compatibility, new DBUS messages are added.
2021-10-28 10:47:46 +01:00
Iago Lopez Galeiras b1994387d3 core: use LSM BPF functions to implement RestrictFileSystems=
It attaches the LSM BPF program when the system manager starts up.

It populates the hash of maps BPF map when services that have
RestrictFileSystems= set start.

It cleans up the hash of maps when the unit cgroup is pruned.

To pass the file descriptor of the BPF map we add it to the keep_fds
array.
2021-10-06 10:52:14 +02:00
alexlzhu 8c35c10d20 core: Add ExecSearchPath parameter to specify the directory relative to which binaries executed by Exec*= should be found
Currently there does not exist a way to specify a path relative to which
all binaries executed by Exec should be found. The only way is to
specify the absolute path.

This change implements the functionality to specify a path relative to which
binaries executed by Exec*= can be found.

Closes #6308
2021-09-28 14:52:27 +01:00
Lennart Poettering 43144be4a1 pid1: add support for encrypted credentials 2021-07-08 09:30:56 +02:00
Xℹ Ruoyao a70581ffb5 New directives PrivateIPC and IPCNamespacePath 2021-03-04 00:04:36 +08:00
Luca Boccassi 93f597013a Add ExtensionImages directive to form overlays
Add support for overlaying images for services on top of their
root fs, using a read-only overlay.
2021-02-23 15:34:46 +00:00
Zbigniew Jędrzejewski-Szmek 2d93c20e5f tree-wide: use -EINVAL for enum invalid values
As suggested in https://github.com/systemd/systemd/pull/11484#issuecomment-775288617.

This does not touch anything exposed in src/systemd. Changing the defines there
would be a compatibility break.

Note that tests are broken after this commit. They will be fixed in the next one.
2021-02-10 14:46:59 +01:00
Topi Miettinen ddc155b2fd New directives NoExecPaths= ExecPaths=
Implement directives `NoExecPaths=` and `ExecPaths=` to control `MS_NOEXEC`
mount flag for the file system tree. This can be used to implement file system
W^X policies, and for example with allow-listing mode (NoExecPaths=/) a
compromised service would not be able to execute a shell, if that was not
explicitly allowed.

Example:
[Service]
NoExecPaths=/
ExecPaths=/usr/bin/daemon /usr/lib64 /usr/lib

Closes: #17942.
2021-01-29 12:40:52 +00:00
Lennart Poettering 3bdc25a4cf core: make NotifyAccess= in combination with RootDirectory=/RootImage= work
Previously if people enabled RootDirectory=/RootImage= and NotifyAccess=
together, things wouldn't work, they'd have to explicitly add
BindReadOnlyPaths=/run/systemd/notify too.

Let's make this implicit. Since both options are opt-in, if people use
them together it would be pointless not also defining the
BindReadOnlyPaths= entry, in which case we can just do it automatically.

See: #18051
2021-01-20 22:39:07 +01:00
Luca Boccassi 5e8deb94c6 core: add DBUS method to bind mount new nodes without service restart
Allow to setup new bind mounts for a service at runtime (via either
DBUS or a new 'systemctl bind' verb) with a new helper that forks into
the unit's mount namespace.
Add a new integration test to cover this.

Useful for zero-downtime addition to services that are running inside
mount namespaces, especially when using RootImage/RootDirectory.

If a service runs with a read-only root, a tmpfs is added on /run
to ensure we can create the airlock directory for incoming mounts
under /run/host/incoming.
2021-01-18 17:24:05 +00:00
Lucas Werkmeister 8d7dab1fda Add truncate: to StandardOutput= etc.
This adds the ability to specify truncate:PATH for StandardOutput= and
StandardError=, similar to the existing append:PATH. The code is mostly
copied from the related append: code. Fixes #8983.
2021-01-15 09:54:50 +01:00
Yu Watanabe db9ecf0501 license: LGPL-2.1+ -> LGPL-2.1-or-later 2020-11-09 13:23:58 +09:00
Zbigniew Jędrzejewski-Szmek fcb7138ca7 test-path: do not fail the test if we fail to start a service because of cgroup setup
The test was failing because it couldn't start the service:

path-modified.service: state = failed; result = exit-code
path-modified.path: state = waiting; result = success
path-modified.service: state = failed; result = exit-code
path-modified.path: state = waiting; result = success
path-modified.service: state = failed; result = exit-code
path-modified.path: state = waiting; result = success
path-modified.service: state = failed; result = exit-code
path-modified.path: state = waiting; result = success
path-modified.service: state = failed; result = exit-code
path-modified.path: state = waiting; result = success
path-modified.service: state = failed; result = exit-code
Failed to connect to system bus: No such file or directory
-.slice: Failed to enable/disable controllers on cgroup /system.slice/kojid.service, ignoring: Permission denied
path-modified.service: Failed to create cgroup /system.slice/kojid.service/path-modified.service: Permission denied
path-modified.service: Failed to attach to cgroup /system.slice/kojid.service/path-modified.service: No such file or directory
path-modified.service: Failed at step CGROUP spawning /bin/true: No such file or directory
path-modified.service: Main process exited, code=exited, status=219/CGROUP
path-modified.service: Failed with result 'exit-code'.
Test timeout when testing path-modified.path

In fact any of the services that we try to start may fail, especially
considering that we're doing some rogue cgroup operations. See
https://github.com/systemd/systemd/pull/16603#issuecomment-679133641.
2020-10-22 11:05:17 +02:00
Lennart Poettering 74e1252072 execute: add helper for checking if root_directory/root_image are set in ExecContext 2020-10-01 11:02:11 +02:00
Zbigniew Jędrzejewski-Szmek 5e98086d16 core: remember when we set ExecContext.mount_apivfs
No functional change intended so far.
2020-09-24 10:03:18 +02:00
Topi Miettinen 9df2cdd8ec exec: SystemCallLog= directive
With new directive SystemCallLog= it's possible to list system calls to be
logged. This can be used for auditing or temporarily when constructing system
call filters.

---
v5: drop intermediary, update HASHMAP_FOREACH_KEY() use
v4: skip useless debug messages, actually parse directive
v3: don't declare unused variables with old libseccomp
v2: fix build without seccomp or old libseccomp
2020-09-15 12:54:17 +03:00
Lennart Poettering bb0c0d6f29 core: add credentials logic
Fixes: #15778 #16060
2020-08-25 19:45:35 +02:00
Lennart Poettering 4e39995371 core: introduce ProtectProc= and ProcSubset= to expose hidepid= and subset= procfs mount options
Kernel 5.8 gained a hidepid= implementation that is truly per procfs,
which allows us to mount a distinct once into every unit, with
individual hidepid= settings. Let's expose this via two new settings:
ProtectProc= (wrapping hidpid=) and ProcSubset= (wrapping subset=).

Replaces: #11670
2020-08-24 20:11:02 +02:00
Luca Boccassi b3d133148e core: new feature MountImages
Follows the same pattern and features as RootImage, but allows an
arbitrary mount point under / to be specified by the user, and
multiple values - like BindPaths.

Original implementation by @topimiettinen at:
https://github.com/systemd/systemd/pull/14451
Reworked to use dissect's logic instead of bare libmount() calls
and other review comments.
Thanks Topi for the initial work to come up with and implement
this useful feature.
2020-08-05 21:34:55 +01:00
Luca Boccassi 18d7370587 service: add new RootImageOptions feature
Allows to specify mount options for RootImage.
In case of multi-partition images, the partition number can be prefixed
followed by colon. Eg:

RootImageOptions=1:ro,dev 2:nosuid nodev

In absence of a partition number, 0 is assumed.
2020-07-29 17:17:32 +01:00
Zbigniew Jędrzejewski-Szmek 56a13a495c pid1: create ro private tmp dirs when /tmp or /var/tmp is read-only
Read-only /var/tmp is more likely, because it's backed by a real device. /tmp
is (by default) backed by tmpfs, but it doesn't have to be. In both cases the
same consideration applies.

If we boot with read-only /var/tmp, any unit with PrivateTmp=yes would fail
because we cannot create the subdir under /var/tmp to mount the private directory.
But many services actually don't require /var/tmp (either because they only use
it occasionally, or because they only use /tmp, or even because they don't use the
temporary directories at all, and PrivateTmp=yes is used to isolate them from
the rest of the system).

To handle both cases let's create a read-only directory under /run/systemd and
mount it as the private /tmp or /var/tmp. (Read-only to not fool the service into
dumping too much data in /run.)

$ sudo systemd-run -t -p PrivateTmp=yes bash
Running as unit: run-u14.service
Press ^] three times within 1s to disconnect TTY.
[root@workstation /]# ls -l /tmp/
total 0
[root@workstation /]# ls -l /var/tmp/
total 0
[root@workstation /]# touch /tmp/f
[root@workstation /]# touch /var/tmp/f
touch: cannot touch '/var/tmp/f': Read-only file system

This commit has more changes than I like to put in one commit, but it's touching all
the same paths so it's hard to split.
exec_runtime_make() was using the wrong cleanup function, so the directory would be
left behind on error.
2020-07-14 19:47:15 +02:00
Luca Boccassi d4d55b0d13 core: add RootHashSignature service parameter
Allow to explicitly pass root hash signature as a unit option. Takes precedence
over implicit checks.
2020-06-25 08:45:21 +01:00
Lennart Poettering 6b000af4f2 tree-wide: avoid some loaded terms
https://tools.ietf.org/html/draft-knodel-terminology-02
https://lwn.net/Articles/823224/

This gets rid of most but not occasions of these loaded terms:

1. scsi_id and friends are something that is supposed to be removed from
   our tree (see #7594)

2. The test suite defines an API used by the ubuntu CI. We can remove
   this too later, but this needs to be done in sync with the ubuntu CI.

3. In some cases the terms are part of APIs we call or where we expose
   concepts the kernel names the way it names them. (In particular all
   remaining uses of the word "slave" in our codebase are like this,
   it's used by the POSIX PTY layer, by the network subsystem, the mount
   API and the block device subsystem). Getting rid of the term in these
   contexts would mean doing some major fixes of the kernel ABI first.

Regarding the replacements: when whitelist/blacklist is used as noun we
replace with with allow list/deny list, and when used as verb with
allow-list/deny-list.
2020-06-25 09:00:19 +02:00
Luca Boccassi 0389f4fa81 core: add RootHash and RootVerity service parameters
Allow to explicitly pass root hash (explicitly or as a file) and verity
device/file as unit options. Take precedence over implicit checks.
2020-06-23 10:50:09 +02:00
Lennart Poettering f3dc6af20f core: automatically update StandardOuput=syslog to =journal (and similar for StandardError=)
Let's go one step further and upgrade implicitly. Usually =syslog
assignments are historic artifacts only. Let's upgrade the lines
automatically, and politely suggest people update their unit
files/configuration (and drop the lines altogether, without
replacement).

Fixes: #15807
2020-05-15 00:05:46 +02:00
Zbigniew Jędrzejewski-Szmek ad21e542b2 manager: add CoredumpFilter= setting
Fixes #6685.
2020-04-09 14:08:48 +02:00