Rename nspawn's --user=NAME option to --uid=NAME for selecting the
container user. The -u short option is preserved. --user=NAME and
--user NAME are still accepted but emit a deprecation warning. A
pre-parsing step stitches the space-separated --user NAME form into
--user=NAME before getopt sees it, preserving backwards compatibility
despite --user now being an optional_argument.
Repurpose --user (without argument) and --system as standalone
switches for selecting the runtime scope (user vs system service
manager).
Replace all uses of the arg_privileged boolean with
arg_runtime_scope comparisons throughout nspawn. The default scope
is auto-detected from the effective UID.
Co-developed-by: Claude Opus 4.6 <noreply@anthropic.com>
Move register_machine() and unregister_machine() from
vmspawn-register.{c,h} into shared machine-register.{c,h} so both
nspawn and vmspawn can use the same implementation.
The unified register_machine() uses varlink first (for richer
features like SSH support and unit allocation) with a D-Bus
RegisterMachineWithNetwork fallback for older machined. The
interface adds a class parameter ("vm" or "container") and
local_ifindex for nspawn's network interface support.
The unified unregister_machine() similarly tries varlink first
(io.systemd.Machine.Unregister) before falling back to D-Bus.
Both register_machine() and unregister_machine() only log at debug
level internally, leaving error/notice logging to callers.
Add register_machine_with_fallback() which tries system and/or user
scope registration based on a RuntimeScope parameter
(_RUNTIME_SCOPE_INVALID for both), and
unregister_machine_with_fallback() as its counterpart. Both use
RET_GATHER() to collect errors from each scope.
Make --register= a tristate (yes/no/auto) defaulting to auto. When
set to auto, registration failures are logged at notice level and
ignored. When set to yes, failures are fatal.
Co-developed-by: Claude Opus 4.6 <noreply@anthropic.com>
We expose this via --private-users-delegate= which takes the number of
ranges to delegate. On top of delegating the ranges, we also mount in
the nsresourced socket and the mountfsd socket so that nested containers
can use nsresourced to allocate from the delegated ranges and mountfsd to
mount images.
Finally, we also create /run/systemd/dissect-root with systemd-tmpfiles to
make sure it is always available as unpriv users won't be able to create it
themselves.
Aside from the usual boilerplate of moving the shared logic to shared/,
we also rework the implementation of --bind-user= to be similar to what
we'll do in systemd-vmspawn. Instead of messing with the nspawn container
user namespace, we use idmapped mounts to map the user's home directory on
the host to the mapped uid in the container.
Ideally we'd also use the "userdb.transient" credentials to provision the
user records, but this would only work for booted containers, whereas the
current logic works for non-booted containers as well.
Aside from being similar to how we'll implement --bind-user= in vmspawn,
using idmapped mounts also allows supporting --bind-user= without having to
use --private-users=.
This mimics the switch of the same name from nspawn: it controls whether
we expect a READY=1 message from the payload or not. Previously we'd
always expect that. This makes it configurable, just like it is in
nspawn.
There's one fundamental difference in behaviour though: in nspawn it
defaults to off, in vmspawn it defaults to on. (for historical reasons,
ideally we'd default to on in both cases, but changing is quite a compat
break both directly and indirectly: since timeouts might get triggered).
Prior to this change, no user shell can be specified in the user
records passed into a container via --bind-user=. This new option
allows users to:
1. When false (the default), continue to specify no user shell for
each bound user record, resulting in the use of the container's
default shell for bound users.
2. When true, include each host user's shell in the corresponding
user record passed into a container (via --bind-user=).
3. When an absolute path, set that path as the user shell for each
user record passed into a container (via --bind-user=).
This does not change the existing behavior, but allows users to
opt-in to either copy the shells specified by the host user records
or override the shell explicitly by path.
This is needed for dnf5. But dnf-4 doesn't know about it. So also add a hint to
skip the option with dnf-4. We can drop this later when dnf5 is the default
everywhere.
Also, s/vim-minimal/nano/. Nano is the default editor in Fedora since
https://fedoraproject.org/wiki/Changes/UseNanoByDefault.
This is useful when the previous invocation is unexpectedly killed.
Otherwise, if systemd-nspawn is killed forcibly, then unix-export
directory is not cleared and unmounted, and the subsequent invocation
will fail. E.g.
===
[ 18.895515] TEST-13-NSPAWN.sh[645]: + machinectl start long-running
[ 18.945703] systemd-nspawn[1387]: Mount point '/run/systemd/nspawn/unix-export/long-running' exists already, refusing.
[ 18.949236] systemd[1]: systemd-nspawn@long-running.service: Failed with result 'exit-code'.
[ 18.949743] systemd[1]: Failed to start systemd-nspawn@long-running.service.
===
It's sometimes very useful to be able to terminate a container quickly
but cleanly while talking to it. Introduce a hotkey for that: ^]^]p for
powering it off. In similar style add ^]^]r for rebooting it.
I don't actually need this anymore since we're going with a
unit based approach for the containers stuff internally so
let's just revert it.
Fixes#34085
This reverts commit ce2291730d.
This allows for example forcing to use /sbin/init instead of always
using /usr/lib/systemd/systemd if it exists. Or it allows using a
different path altogether.
When starting a container with --user, the new uid will be resolved and switched to
only in the inner child, at the end of the setup, by spawning getent. But the
credentials are set up in the outer child, long before the user is resolvable,
and the directories/files are made only readable by root and read-only, which
means they cannot be changed later and made visible to the user.
When this particular combination is specified, it is obvious the caller wants
the single-process container to be able to use credentials, so make them world
readable only in that specific case.
Fixes https://github.com/systemd/systemd/issues/31794
This also replaces the Fedora download example with another one from
Ubuntu, since Fedora's images these days no longer qualify as DDIs, they
have no distinctive partition type UUIDs set for multiple of their
partitions, hence the images cannot be booted. A bit sad. Let's provide
a command that just works in its place.
owneridmap bind option will map the target directory owner from inside the
container to the owner of the directory bound from the host filesystem.
This will ensure files and directories created in the container will be owned
by the directory owner of the host filesystem. All other users will remain
unmapped. Files to be written as other users in the container will not be
allowed.
Resolves: #27037
Common sense says that to "try" something means "to not fail if
something turns out not to be possible", thus do not make this
combination a hard error.
The actual implementation ignores any --link-journal= setting when
--ephemeral is in effect, so the semantics are upheld.
As I noticed a lot of missing information when trying to implement checking
for missing info. I reimplemented the version information script to be more
robust, and here is the result.
Follow up to ec07c3c80b
This tries to add information about when each option was added. It goes
back to version 183.
The version info is included from a separate file to allow generating it,
which would allow more control on the formatting of the final output.