Extend the 'install' keyword for executable definitions to accept four
modes—'yes', 'no', 'both', and 'static'—to elegantly manage the creation
and installation of both shared and statically-linked (.standalone) binaries.
- 'yes' / 'no': Standard behavior (mapped to true/false).
- 'both': Installs both the shared and static variants.
- 'static': Installs the static variant under the original name, while
suffixing the uninstalled shared variant with '.shared'.
With this change, any arbitrary executable can now have its `.standalone`
variant built on demand simply by invoking `ninja <target>.standalone`.
For example, `varlinkctl` did not previously support a standalone variant,
but it can now be built explicitly via `ninja varlinkctl.standalone`.
These `.standalone` binaries are not built by default unless explicitly
specified as a ninja target or enabled via `-Dstandalone-binaries=true`.
Thus, the default build time should remain unaffected.
This centralisation eliminates a massive amount of boilerplate and duplicated
target declarations across almost all subdirectories (e.g., systemd-repart,
systemd-tmpfiles, systemd-shutdown, and systemd-report tools).
This makes each `foo_cflags` dependency define a `SYSTEMD_CFLAGS_MARKER_FOO`
macro, and checks if the macro is set when headers provided by external
libraries are included.
With this, we can fail fast at compile time if necessary `_cflags`
dependencies are omitted in meson.build. Missing dependencies found by this
mechanism have been added across the tree.
Compile the contents of a few essential target unit files
(graphical.target, multi-user.target, rescue.target, etc.) into the
manager binary, with comments stripped, and fall back to those built-in
copies when no fragment is found on disk. This lets the manager reach a
usable state even on a system that ships none of these unit files, e.g.
in minimal environments or one-off chroots.
On-disk files always take precedence (masks included), as the fallback is
only consulted when nothing is found in the lookup paths. The unit file
list is defined in units/meson.build and embedded via a small generator
script; 'units' is now processed before 'src/core' so the list is
available there.
The set of units and services is selected that should allow for a normal
operation of starting/stopping/restarting, of the machine. The services
all use SuccessAction=…, so they don't require any binaries to be
installed.
sigpwr.target is included, even though it doesn't do anything useful.
The same is true in normal installations. We might want to change it
do something useful there too.
After stripping, in an unoptimized build with glibc, we get a 8.7 MB binary:
$ file build-static/systemd
build-static/systemd: ELF 64-bit LSB executable, x86-64, version 1 (GNU/Linux), statically linked, BuildID[sha1]=1ec004bf61b775d284d909a818a3c4f63f83f055, for GNU/Linux 3.2.0, stripped
$ ls -lh build-static/systemd
-rwxr-xr-x 1 zbyszek zbyszek 8.7M Jun 30 14:07 build-static/systemd
This effectively reverts the meson config changes introduced in
0c6186695a. I wasn't happy with that form
back when it was commited, and in hindsight, I like it even less. Let's
just add a new option that hopefully is easier to understand and will
work better when new functionality is added in the future.
Now there are two options:
link-executor-shared (boolean, defaults to true)
— "link (separate) systemd-executor to libsystemd-shared.so and libsystemd-core.so"
systemd-multicall-binary (also boolean, defaults to false)
— "link systemd+systemd-executor as a single binary"
Build directories will need to be recreated again, sorry!
Allow systemd-executor to be compiled into a single binary.
The existing -Dlink-executor-shared=true|false is extended to also
allow -Dlink-executor-shared=single (*). The new mode is opt-in,
to allow experimentation and introduce this smoothly.
This saves a little space, but not as much as I expected:
$ ls -l build/{systemd,systemd-executor} build-new/systemd
-rwxr-xr-x 1 zbyszek zbyszek 631520 May 25 22:44 build/systemd
-rwxr-xr-x 1 zbyszek zbyszek 670464 May 25 22:44 build/systemd-executor
-rwxr-xr-x 1 zbyszek zbyszek 1214488 May 25 22:45 build-new/systemd
(This is with -Dbuildtype=debugoptimized -Db_lto=true).
The combined binary is slightly smaller than the sum of the separate
ones, but not much. In both cases, the binaries are linked to
libsystemd-core which is 10MB, so the size of the binaries themselves
doesn't make much of a difference. The executor needs exec-invoke.c
which is huge and not shared with anything else.
Longer term, I want to allow systemd to be linked statically. In
that case, having systemd-executor separate would be very painful.
So the option to use a multicall binary will be necessary.
Previously, we stored the resolved path to systemd-executor and
used it argv[0]. I don't think this was useful. After all, normally
we would use the non-resolved original path as argv[0]. So that
part is dropped, and the resolved path is only logged, but
"systemd-executor" is always used as argv[0]. This makes the
multicall binary work reliably, no matter what the actual file
name is.
(*) This means that compat as the commandline level is maintained:
'meson setup build -Dlink-executor-shared=true …' works as before.
Unfortunately, when using an existing build directory, meson chokes
on the type change and refuses to reconfigure the directory or change
the option or do anything useful. I think meson is DTWT here, but
this is hard to fix. So the build directory probably needs to be
recreated.
Drop the -fundamental suffix from src/fundamental/ headers in favor of names
that match their src/basic/ or src/shared/ counterparts (e.g.
macro-fundamental.h -> macro.h, assert-fundamental.h -> assert-util.h,
cleanup-fundamental.h -> cleanup-util.h). Rename src/basic/{btrfs,label}.{c,h}
to use the -util suffix to match the existing shared/btrfs-util and
shared/label-util siblings. Rename src/shared/mkdir-label.{c,h} to mkdir.{c,h}
and src/shared/tmpfile-util-label.{c,h} to tmpfile-util.{c,h} to match the
corresponding src/basic names.
This saves us from having to come up with separate names for files that do
the same thing across tiers, and it makes it easier to move stuff between
src/fundamental, src/basic and src/shared: consumers just #include "foo.h"
and pick up whichever tier their -I path resolves to first, so call sites
don't need to be updated when an API moves between layers.
Where a higher-tier wrapper exists (e.g. src/basic/macro.h wrapping
src/fundamental/macro.h), the wrapper uses an explicit "../fundamental/foo.h"
or "../basic/foo.h" relative include for the lower-tier header. We can't use
GCC's #include_next directive for this — when the wrapper is reachable both
via same-dir-as-source lookup and via -I (e.g. -Isrc/shared) for the
directory it lives in, #include_next advances by exactly one slot in libcpp's
internal directory chain and lands on the same physical directory it was
already in, never reaching the lower-tier sibling (see make_cpp_dir() in
gcc/libcpp/files.cc:1986).
To make sure the right headers are always picked up, the include directories
are reordered so that e.g. src/shared always takes priority over src/basic and
similar for the other directories.
Co-developed-by: Claude Opus 4.7 <noreply@anthropic.com>
Methods:
- `io.systemd.Job.List` — list all queued jobs or look up by `id`/`unit`
name, with streaming support. Uses context/runtime split: `JobContext`
(Unit, JobType) and `JobRuntime` (Id, State, Result,
ActivationDetails). Follows the same SELinux and parameter-conflict
patterns as `io.systemd.Unit.List`.
- `io.systemd.Job.Cancel` — cancel a specific job by ID, with SELinux
and polkit authorization.
- `io.systemd.Job.ClearAll` — cancel all pending jobs, with SELinux and
polkit authorization.
Our baseline glibc is 2.34, which merged libdl, libpthread (the
dependency('threads') target), and librt into libc. Empty .so/.a stubs
remain for backward compatibility with old binaries, but new builds
resolve dl_*, pthread_*, mq_*, timer_*, etc. directly from libc.
On musl the same libraries are likewise empty stubs.
Drop the libdl, threads, and librt entries from every meson.build, and
remove the now-stale 'Libs.private: -lrt -pthread' from libudev.pc.in
since both flags resolve to empty link-time stubs on glibc 2.34+ and
musl.
Verified with readelf -d that libsystemd.so, libudev.so, and systemd no
longer carry DT_NEEDED entries for libdl/libpthread/librt.
The kernel Live Update Orchestrator (LUO) exposes /dev/liveupdate, which
allows userspace to hand a set of "preservable" kernel objects to the
new kernel across a kexec-based reboot. For now it only supports memfds,
with more object types (virtio devices, etc.) expected to be added later.
This is a natural fit for systemd's FD Store feature: services hand
memfds (containing serialized state or other service data) to PID 1 via
FDSTORE=1 sd_notify() messages, and get them back on their next start.
Today this works across service restarts, soft reboots and
initrd→rootfs transitions. With LUO we can extend the same mechanism to
work across kexec, too.
The protocol on the PID 1 side works roughly as follows:
* All preservable fds are collected into a single LUO session named
"systemd". Each FD gets uploaded with a token. Token 0 in that session
is reserved for a "mapping" memfd, which carries a JSON object
describing how to dispatch the other tokens back to units on the next
boot:
{
"foo.service": [
{ "type": "fd", "name": "stateA", "token": 1 },
{ "type": "fd", "name": "stateB", "token": 2 }
],
...
}
unit IDs are used as the unit identifier, as they're stable
across daemon-reexec, switch-root and kexec. token refers to the
LUO token assigned to the object in the session.
* On shutdown for MANAGER_KEXEC, just before manager_free(), systemd
walks all services and serializes their persistent fd store contents
(fds + FDNAMEs + unit IDs) into a JSON memfd. The FDs themselves are
gathered into a FDSet to be kept around. The fdset and the
serialization memfd are passed to systemd-shutdown via the
SYSTEMD_LUO_SERIALIZE_FD environment variable providing the fd number,
so the actual LUO session creation and ioctls can happen as the very
last step before kexec (shutdown implementation is the next commit).
* On boot, manager_luo_restore_fd_stores() opens /dev/liveupdate,
tries to retrieve the "systemd" session, reads the mapping memfd,
then for each entry retrieves the fd from the session and attempts
to attach it to the matching unit's fd store.
* The FDs are injected in the appropriate unit's FD stores using the
same mechanism as the LISTEN_FDS propagation that was set up earlier.
Non-kexec shutdown paths are unaffected: if MANAGER_KEXEC is not the
final objective, no serialization file is produced and no LUO session
is ever created. Likewise if /dev/liveupdate does not exist, nothing
happens.
Move the existing (partial) service context builder from varlink-unit.c into its own varlink-service.c file, following the pattern established by other unit type context builders (varlink-path.c, varlink-scope.c, etc.). No functional change.
Add a new RestrictFileSystemAccess= boolean setting in the [Manager] section of
system.conf that enforces execution only from signed dm-verity block
devices and the initramfs during early boot.
When RestrictFileSystemAccess=yes is set, PID1 loads a BPF LSM program early in boot
that:
Integrity tracking (self-populating, no userspace involvement):
- bdev_setintegrity: records dm-verity signature status in a BPF hash
map when the kernel signals device integrity via
security_bdev_setintegrity()
- bdev_free_security: removes devices from the map on teardown
Execution enforcement (deny-default policy):
- bprm_check_security: blocks execve() from untrusted sources
- mmap_file: blocks PROT_EXEC mmap (shared libs, anonymous exec memory)
- file_mprotect: blocks W->X transitions (JIT, libffi, etc.)
Trust anchors:
- Signed dm-verity volumes (sig_valid flag in the BPF map)
- Initramfs (s_dev captured at load time, cleared after switch_root)
- Everything else is denied (tmpfs, procfs, sysfs, anonymous PROT_EXEC)
PID1 requires dm-verity require_signatures=1 to be enabled and refuses
to load the BPF program otherwise, ensuring the kernel enforces that all
dm-verity devices carry valid signatures.
After attach, PID1 extracts owned FDs from the skeleton (link FDs +
.bss map FD) and lets the skeleton be destroyed. The dup'd link FDs
keep programs attached via the kernel reference chain (link FD ->
bpf_link -> bpf_prog -> bpf_map). Destroying the skeleton unmaps the
.bss page from PID1's address space so no BPF state is readable via
/proc/1/mem. The .bss map FD is retained for targeted writes (clearing
initramfs_s_dev after switch_root via mmap).
Signed-off-by: Christian Brauner <brauner@kernel.org>
Add varlink context and runtime builders for .timer units:
TimerContext: MonotonicTimers (with MonotonicTimerBase enum), CalendarTimers, Unit, OnClockChange, OnTimezoneChange, AccuracyUSec, RandomizedDelayUSec, RandomizedOffsetUSec, FixedRandomDelay, Persistent, WakeSystem, RemainAfterElapse, DeferReactivation
TimerRuntime: Result (TimerResult enum), NextElapseUSecRealtime, NextElapseUSecMonotonic, LastTriggerUSec
MonotonicTimerSpec and CalendarTimerSpec are separate types since they have different value types (int vs string). MonotonicTimerBase and TimerResult are proper varlink enum types.
Compared to the old io-systemd-Unit-List branch, this adds RandomizedOffsetUSec and DeferReactivation (both present in D-Bus but previously missing), and adds full runtime fields.
Co-developed-by: Claude Opus 4.6 <noreply@anthropic.com>
Add varlink context and runtime builders for .swap units:
SwapContext: What, Priority, Options, TimeoutUSec, ExecActivate, ExecDeactivate
SwapRuntime: ControlPID, Result, CleanResult, UID, GID (SwapResult enum)
SwapResult is exposed as a proper varlink enum type. Runtime follows the same pattern as MountRuntime (ControlPID, Result, CleanResult, ref UID/GID).
The integration test is conditional since swap units may not be present on all systems.
Co-developed-by: Claude Opus 4.6 <noreply@anthropic.com>
Add varlink context and runtime builders for .scope units:
ScopeContext: OOMPolicy (enum), RuntimeMaxUSec, RuntimeRandomizedExtraUSec, TimeoutStopUSec
ScopeRuntime: Result (ScopeResult enum)
Both OOMPolicy and ScopeResult are exposed as proper varlink enum types.
Co-developed-by: Claude Opus 4.6 <noreply@anthropic.com>
Add varlink context and runtime builders for .path units:
PathContext: Paths (array of PathType enum + path specs), Unit, MakeDirectory, DirectoryMode, TriggerLimit
PathRuntime: Result (PathResult enum)
Both PathType and PathResult are exposed as proper varlink enum types.
Co-developed-by: Claude Opus 4.6 <noreply@anthropic.com>
The six .bpf.c files and their shared .bpf.h headers now live directly
under src/bpf/, rather than scattered across src/core/bpf/<prog>/,
src/network/bpf/<prog>/ and src/nsresourced/bpf/<prog>/.
All BPF compilation logic — the BPF_FRAMEWORK determination (clang/gcc/
bpftool/llvm-strip lookups), flag and command construction, vmlinux.h
handling, the bpf_programs list and the loop that builds the unstripped
object, the stripped object and the skeleton header for each program —
moves into src/bpf/meson.build. The top-level meson.build only keeps
option handling and the libbpf dependency. subdir('src/bpf') is pulled
up before config.h generation so that BPF_FRAMEWORK, HAVE_VMLINUX_H and
ENABLE_SYSCTL_BPF land in conf in time.
Skeleton wrapper headers (<prog>-skel.h) are now emitted by a
configure_file() template (src/bpf/bpf-skel-wrapper.h.in) at meson
setup, replacing the previously checked-in shims of the same name.
Consumer #include paths are flattened:
"bpf/<prog>/<prog>-skel.h" becomes "<prog>-skel.h",
"bpf/<prog>/<prog>-api.bpf.h" becomes "<prog>-api.bpf.h". src/bpf is
added to includes so the shared BPF headers resolve.
sysctl-write-event.h, now shared between userspace (networkd-sysctl.c)
and BPF (sysctl-monitor.bpf.c) from a single location, gains guarded
includes so pid_t and uint64_t resolve on both sides: vmlinux.h in the
BPF case (selected via __bpf__), stdint.h + sys/types.h otherwise.
It was actually intended to load libmount very early, as it is
needed by more than just mount units, such as umount_recursive(),
bind_remount_recursive(), get_sub_mounts(), etc.
Fixes https://github.com/systemd/systemd/issues/39994
This reverts commit 46b4b33c25.
Quite often we need to specify include_directories('.'). Normally, meson
does this automatically, but we specify implicit_include_directories : false,
see 30d20907bd for an explanation.
Passing the include_directories argument through the template layers was rather
cumbersome. Let's simplify things by always including the directory of the
first source file. This makes the definitions simpler, at the cost of having an
unnecessary include directory in the list in some cases.
(Tests are excluded from this change, because they happen to not need this, but
also because some tests have source[0] which is a custom target, and we'd need
newer meson to support that.)
Instead of skipping libcore entirely when libmount is not available,
let's only compile out the pieces that need libmount. This makes the
meson logic much less complex and allows systemd-analyze to be built
when libmount is not available.
Currently, if the libmount feature is disabled, we don't build
libshared and as a result skip building every other executable as
well. Among other things, this makes our nodeps CI builds kind of
pointless since hardly any code will be compiled.
Let's improve on the situation by making libmount properly optional
in libshared. Then, we only skip building the executables that
actually need libmount.
test-shift-uid.c doesn't actually use anything from libacl. It all goes
through shared/, and the dep there is enough.
Same for the coredump stuffi, logind and core/.
And pstore doesn't use it at all, neither directly or indirectly.
Then, move syscall definitions to the wrapper, and prototypes are moved
to relevant headers.
This also adds checks for add_key() and request_key(), as one day
glibc may be going to add some of them separatedly.
The check for fspick in meson.build is dropped, as it is currently
unused in our code.
This also moves
- basic/missing_bpf.h -> include/override/linux/bpf.h,
- basic/missing_keyctl.h -> include/override/linux/keyctl.h.
Yu Watanabe
Zbigniew Jędrzejewski-Szmek
Daan De Meyer
Luca Boccassi
Ivan Kruglov
Christian Brauner
Yaping Li
Luiz Amaral
Zbigniew Jędrzejewski-Szmek
Mike Yuan
Daan De Meyer
Lennart Poettering