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).
This beefs up the cgroup logic, adding --slice=, --property= to vmspawn
the same way it already exists in nspawn.
There are a bunch of differences though: we don't delegate the cgroup
access in the allocated unit (since qemu wouldn't need that), and we do
registration via varlink not dbus. Hence, while this follows a similar
logic now, it differs in a lot of details.
This makes in particular one change: when invoked on the command line
we'll only add the qemu instance to the allocated scope, not the vmspawn
process itself (this follows more closely how nspawn does this where
only the container payload has its scope, not nspawn itself). This is
quite tricky to implement: unlike in nspawn we have auxiliary services
to start, with depencies to the scope. This means we need to start the
scope early, so that we know the scope's name. But the command line to
invoke is only assembled from the data we learn about the auxiliary
services, hence much later. To addres we'll now fork off the child that
eventually will become early, then move it to a scope, prepare the
cmdline and then very late send the cmdline (and the fds we want to
pass) to the prepared child, which then execs it.
So far, machined strictly tracked the "leader" process of a machine,
i.e. the topmost process that is actually the payload of the machine.
Its runtime also defines the runtime of the machine, and we can directly
interact with it if we need to, for example for containers to join the
namespaces, or kill it.
Let's optionally also track the "supervisor" process of a machine, i.e.
the host process that manages the payload if there is one. This is
generally useful info, but in particular is useful because we might need
to communicate with it to shutdown a machine without cooperation of the
payload. Traditionally we did this by simply stopping the unit of the
machine, but this is not doable now that the host machined can be used
to track per-user machines.
In the long run we probably want a more bespoke protocol between
machined and supervisors (so that we can execute other commands too,
such as request cooperative reboots/shutdowns), but that's for later.
Some environments call the concept "monitor" rather than "supervisor" or
use some other term. I stuck to "supervisor" because nspawn uses this,
and ultimately one name is as good as another.
And of course, in other implementations of VM managers of containers
there might not be a single process tracking each VM/container. Because
of this, the concept of a supervisor is optional.
Now that unpriv clients can register machines, let's register their UID
too. This allows us to do two things:
1. make sure the scope delegation is assigned to the right UID (so that
the unpriv user can actually create cgroups below the delegated
scope)
2. permit certain types of access (i.e. killing, or pty access) to the
client without auth if it owns the machine.
Continuation of #37960.
The same concern as expalined in #37960 exists also in
missing_syscall.h. If we use enough new glibc, a function we want to use
may be already provided by glibc, but our baseline glibc may not. And it
is hard to detect in our daily development.
This moves all prototypes of syscalls to relevant headers, and missing
syscall functions are defined in relevant .c files of libc wrapper. This
way, we can use usual header as is, e.g. when we want to write code with
`move_mount()`, we can simply use sys/mount.h without checking if it is
supported by our baseline glibc.
- pass our system include directories to make generators use our libc
wrappers and latest kernel headers,
- include relevant headers in generated gperf file,
- use files() rather than find_program(), as the result of
find_program() cannot be passed to 'input' of custom_target(),
- move generate-bpf-delegate-configs.py to src/core/, as it is only used
by libcore.
Add a small paragraph explaining how BPF token works, how it's being
created and its relationship between the BPF filesystem.
Move all the relevant documentation in the PrivateBPF= section and let
point all the BPFDelegate* options to that one.
To implement --bind-user in systemd-vmspawn, we need a transient
version of these credentials. These are useful when the home directory
of the user is mounted into the container/vm and every trace of the user
will be (mostly) gone again when the container/vm is shut down.
closes#37602, see there for extra motivation and considered
alternatives.
On typical systems, only few services need to create SUID/SGID files.
This often is limited to the user explicitly setting suid/sgid, the
`systemd-tmpfiles*` services, and the package manager. Allowing a
default to globally restrict creation of suid/sgid files makes it easier
to apply this restriction precisely.
## testing done
- built on aarch64-linux and x86_64-linux
- ran a VM test on x86_64-linux, checking for:
- VM system boots successfully
- defaults apply (both `yes`, `no`, and undefined)
- systemd tmpfiles can set suid/sgid on journal log path
- Other services explicitly defining `RestrictSUIDSGID=no` can create
suid files
Add a new option PrivateBPF= to mount a new instance of bpffs within a
namespace.
PrivateBPF= can be set to "no" to use the host bpffs in readonly mode
and "yes" to do a new mount.
The mount is done with the new fsopen()/fsmount() API because in future
we'll hook some commands between the two calls.
Based on https://github.com/systemd/systemd/issues/7820, this adds support for
quota enforcement to State, Cache, and Log exec directories.
* Add new directives, StateDirectoryQuota=, CacheDirectoryQuota=, and
LogDirectoryQuota=, to define quotas as percentages (hard limits for
blocks and inodes) or absolute values (hard limits for blocks only).
* Add new directives, StateDirectoryQuotaAccounting=,
CacheDirectoryQuotaAccounting= and LogDirectoryQuotaAccounting= to keep
track of storage quotas but not enforce them (effectively just assigning
a project ID to defined exec directories).
Example:
```
StateDirectory=quotadir
StateDirectoryQuota=1%
Jan 06 22:55:46 abeltran: Storage quotas set for /var/lib/private/quotadir. Block limit = 2639404, inode limit = 671088
root@abeltran:/var/lib/private# lsattr -pR
3153000189 --------------e----P-- ./quotadir
root@abeltran:/var/lib/private# repquota -P /datadrive
*** Report for project quotas on device /dev/sdc1
Block grace time: 7days; Inode grace time: 7days
Block limits File limits
Project used soft hard grace used soft hard grace
----------------------------------------------------------------------
#0 -- 213200 0 0 4086 0 0
#3153000189 -- 2639404 0 2639404 2 0 671088
```
ssh-generator: generate /etc/issue.d/ with VSOCK ssh info data
I find myself trying to log into a fresh ParticleOS VM started via
systemd-vmspawn all the time, but I don't know its CID. Let's show it on
the getty screen, to make it immediately visible.
Related to https://github.com/systemd/systemd/pull/37641.
The name "transient settings" was used in docs/TRANSIENT-SETTINGS.md.
Using "setting" helps distinguish this from D-Bus "properties", which are
a much larger set, partially overlapping.
Currently, when running "systemctl preset-all --root=xxx" in mkosi
to enable/disable units for initrds, the system presets are used.
The problem with this approach is that the system presets are written
for the system, and that is not necessarily ideal for an initrd, but we
still want to use the same packages in the initrd that we install in the
system, so let's introduce a separate directory for initrd presets which
is used to pick up preset files from when we detect that we're configuring
an initrd (by looking for /etc/initrd-release).
We also introduce a systemd preset file for the initrd, which is based on
the system one, except with all the stuff unnecessary for the initrd removed.
I find myself trying to log into a fresh ParticleOS VM started via
systemd-vmspawn all the time, but I don't know its CID. Let's show it on
the getty screen, to make it immediately visible.
ephemeral/ephemeral-import are described as possible '--mutable' options but
not present in the list. Note, "systemd-sysext --help" lists them correctly.
Alternative to b50f6dbe57
The commit naively returned early from socket_enter_running(), which however
is quite problematic, as the socket will be woken up over and over again
without doing a thing, until we eventually hit Poll/TriggerLimit*=.
On top of that it requires hacks to hold the start job for initrd-switch-root.service
up. Overall I doubt that is the right approach.
Let's instead hook this into our job engine, and try to activate
the service again when some other units are stopped. If all installed
jobs have been run yet we're still seeing the conflict or the manually
selected timeout is reached, fail the socket as before.
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 a new meta value for the `Format=` option, which is equivalent
as specifying `Label=_empty` and `NoAuto=1` for compatibility with
sd-sysupdate.
Closes: https://github.com/systemd/systemd/issues/34596
[1] says:
> Since 0.60.0 the name argument is optional and defaults to the basename of
> the first output
We specify >= 0.62 as the supported version, so drop the duplicate name in all cases
where it is the same as outputs[0], i.e. almost all cases.
[1] https://mesonbuild.com/Reference-manual_functions.html#custom_target
Lennart Poettering
Yu Watanabe
Matteo Croce
Ubuntu
DaanDeMeyer
Christian Hesse
Grimmauld
Andres Beltran
Mike Yuan
Gabríel Arthúr Pétursson
ZIHCO
Zbigniew Jędrzejewski-Szmek
Frede Braendstrup
Vitaly Kuznetsov
Nick Labich
Michael Ferrari