This implements a "storage target mode", similar to what MacOS provides
since a long time as "Target Disk Mode":
https://en.wikipedia.org/wiki/Target_Disk_Mode
This implementation is relatively simple:
1. a new generic target "storage-target-mode.target" is added, which
when booted into defines the target mode.
2. a small tool and service "systemd-storagetm.service" is added which
exposes a specific device or all devices as NVMe-TCP devices over the
network. NVMe-TCP appears to be hot shit right now how to expose
block devices over the network. And it's really simple to set up via
configs, hence our code is relatively short and neat.
The idea is that systemd-storagetm.target can be extended sooner or
later, for example to expose block devices also as USB mass storage
devices and similar, in case the system has "dual mode" USB controller
that can also work as device, not just as host. (And people could also
plug in sharing as NBD, iSCSI, whatever they want.)
How to use this? Boot into your system with a kernel cmdline of
"rd.systemd.unit=storage-target-mode.target ip=link-local", and you'll see on
screen the precise "nvme connect" command line to make the relevant
block devices available locally on some other machine. This all requires
that the target mode stuff is included in the initrd of course. And the
system will the stay in the initrd forever.
Why bother? Primarily three use-cases:
1. Debug a broken system: with very few dependencies during boot get
access to the raw block device of a broken machine.
2. Migrate from system to another system, by dd'ing the old to the new
directly.
3. Installing an OS remotely on some device (for example via Thunderbolt
networking)
(And there might be more, for example the ability to boot from a
laptop's disk on another system)
Limitations:
1. There's no authentication/encryption. Hence: use this on local links
only.
2. NVMe target mode on Linux supports r/w operation only. Ideally, we'd
have a read-only mode, for security reasons, and default to it.
Future love:
1. We should have another mode, where we simply expose the homed LUKS
home dirs like that.
2. Some lightweight hookup with plymouth, to display a (shortened)
version of the info we write to the console.
To test all this, just run:
mkosi --kernel-command-line-extra="rd.systemd.unit=storage-target-mode.target" qemu
modprobe treats "-" and "_" interchangeably, thereby avoiding frequent
errors because some module names contain dashes and others underscores.
Because modprobe@.service unescapes the instance name, an attempt to
start "modprobe@dm-crypt.service" will run "modprobe -abq dm/crypt",
which is doomed to fail. "modprobe@dm_crypt.service" will work as
expected. Thus unescaping the instance name has surprising side effects.
Use "%i" instead.
When --boot is set, and --keep-unit is not, set CoredumpReceive=yes on
the scope allocated for the container. When --keep-unit is set, nspawn
does not allocate the container's unit, so the existing unit needs to
configure this setting itself.
Since systemd-nspawn@.service sets --boot and --keep-unit, add
CoredumpReceives=yes to that unit.
As systemd-journal-upload deals mostly with remote servers, add
some failsafes to its unit to restart on failures.
```
[Service]
Restart=on-failure
RestartSteps=10
RestartMaxDelaySec=60
```
This is primarily supposed to be a 1st step with varlinkifying our
various command line tools, and excercise in how this might look like
across our codebase one day. However, at AllSystemsGo! 2023 it was
requested that we provide an API to do a PCR measurement along with a
matching event log record, and this provides that.
This adds an explicit service for initializing the TPM2 SRK. This is
implicitly also done by systemd-cryptsetup, hence strictly speaking
redundant, but doing this early has the benefit that we can parallelize
this in a nicer way. This also write a copy of the SRK public key in PEM
format to /run/ + /var/lib/, thus pinning the disk image to the TPM.
Making the SRK public key is also useful for allowing easy offline
encryption for a specific TPM.
Sooner or later we should probably grow what this service does, the
above is just the first step. For example, the service should probably
offer the ability to reset the TPM (clear the owner hierarchy?) on a
factory reset, if such a policy is needed. And we might want to install
some default AK (?).
Fixes: #27986
Also see: #22637
Follow-up for d120ce478d
blockdev@.target is used as a synchronization point between
the mount unit and corresponding systemd-cryptsetup@.service.
After the mentioned commit, it doesn't get a stop job enqueued
during shutdown, and thus the stop job for systemd-cryptsetup@.service
could be run before the mount unit is stopped.
Therefore, let's make blockdev@.target conflict with umount.target,
which is also what systemd-cryptsetup@.service does.
Fixes#29336
So, unfortunately oomd uses "io.system." rather than "io.systemd." as
prefix for its sockets. This is a mistake, and doesn't match the
Varlink interface naming or anything else in oomd.
hence, let's fix that.
Given that this is an internal protocol between PID1 and oomd let's
simply change this without retaining compat.
The tool initially just measured the boot phase, but was subsequently
extended to measure file system and machine IDs, too. At AllSystemsGo
there were request to add more, and make the tool generically
accessible.
Hence, let's rename the binary (but not the pcrphase services), to make
clear the tool is not just measureing the boot phase, but a lot of other
things too.
The tool is located in /usr/lib/ and still relatively new, hence let's
just rename the binary and be done with it, while keeping the unit names
stable.
While we are at it, also move the tool out of src/boot/ and into its own
src/pcrextend/ dir, since it's not really doing boot related stuff
anymore.
When booting from virtiofs, we won't be able to find a root block
device. Let's gracefully handle this similar to how we don't fail
if we can't find a GPT partition table.
Before this commit, the hibernate location logic only exists in
the generator. Also, we compare device nodes (devnode_same()) and
clear EFI variable HibernateLocation in the generator too. This is
not ideal though: when the generator gets to run, udev hasn't yet
started, so effectively devnode_same() always fails. Moreover, if
the boot process is interrupted by e.g. battery-check, the hibernate
information is lost.
Therefore, let's split out the logic of finding hibernate location.
The generator only does the initial validation of system info and
enables systemd-hibernate-resume.service, and when the service
actually runs we validate everything again, which includes comparing
the device nodes and clearing the EFI variable. This should make
things more robust, plus systems that don't utilize a systemd-enabled
initrd can use the exact same logic to resume using the EFI variable.
I.e., systemd-hibernate-resume can be used standalone.
Otherwise the root filesystem might still be readonly and
systemd-userdbd fails to start.
Explicitly pick systemd-remount-fs.service instead of local-fs-pre.target
to prevent a dependency cycle.
- add reference to the service unit in the man page,
- fix several indentation and typos,
- replace '(uint64_t) -1' with 'UINT64_MAX',
- drop unnecessary 'continue'.
This makes tmpfiles, sysusers, and udevd invoked in the following order:
1. systemd-tmpfiles-setup-dev-early.service
Create device nodes gracefully, that is, create device nodes anyway
by ignoring unknown users and groups.
2. systemd-sysusers.service
Create users and groups, to make later invocations of tmpfiles and
udevd can resolve necessary users and groups.
3. systemd-tmpfiles-setup-dev.service
Adjust owners of previously created device nodes.
4. systemd-udevd.service
Process all devices. Especially to make block devices active and can
be mountable.
5. systemd-tmpfiles-setup.service
Setup basic filesystem.
Follow-up for b42482af90.
Fixes#28653.
Replaces #28681 and #28732.
This reverts commits 112a41b6ec,
3178698bb5, and
b768379e8b.
The commit 112a41b6ec introduces #28765,
as systemd-tmpfiles-setup.service has ordering after local-fs.target,
but usually the target requires block devices processed by udevd.
Hence, the service can only start after the block devices timed out.
Fixes#28765.
Follow-up for b42482af90.
The commit makes systemd-tmpfiles-setup.service also updates the
permission or owner of device nodes. However, the service does not have
ordering for systemd-udevd.service. So, the service may set different
permission from the one udevd already set.
Fixes#28653.
Replaces #28681.
If emergency.target is started while initrd-parse-etc.service/start is queued,
the initrd-parse-etc job did not get canceled. In parallel to the emergency
units, it eventually runs the service, which starts initrd-cleanup.service,
which in turn isolates initrd-switch-root.target. This stops the emergency
units and effectively starts the initrd boot process again, which likely
fails again like the initial attempt. The system is thus stuck in an endless
loop, never really reaching emergency.target.
With this conflict added, starting emergency.target automatically cancels
initrd-parse-etc.service/start, avoiding the loop.
Without this change, there are no ordering between udevd and tmpfiles,
and if tmpfiles is invoked later it may discard the permission set by
udevd.
Fixes an issue introduced by b42482af90.
Fixes#28588 and #28653.
In it's latest release, agetty will support reading the agetty.autologin
and login.noauth credentials, so let's make sure we import those in our
getty units so they're available to agetty to read.
Some of the new units using systemd-pcrphase are missing the --graceful
flag which causes them to error if the tpm libraries are not installed.
Add --graceful just like in the other pcrphase units to make systemd-pcrphase
exit gracefully if the tpm libraries are missing.
The service has Type=oneshot, which means that the default value of SuccessExitStatus=0.
When multiple vtcon devices are detected, udev will restart the service after each
one. If this happens quickly enough, the old instance will get SIGTERM while it is
still running:
[ 5.357341] (udev-worker)[593]: vtcon1: /usr/lib/udev/rules.d/90-vconsole.rules:12 RUN '/usr/bin/systemctl --no-block restart systemd-vconsole-setup.service
[ 5.357439] (udev-worker)[593]: vtcon1: Running command "/usr/bin/systemctl --no-block restart systemd-vconsole-setup.service"
[ 5.357485] (udev-worker)[593]: vtcon1: Starting '/usr/bin/systemctl --no-block restart systemd-vconsole-setup.service'
[ 5.357537] (udev-worker)[609]: vtcon0: /usr/lib/udev/rules.d/90-vconsole.rules:12 RUN '/usr/bin/systemctl --no-block restart systemd-vconsole-setup.service
[ 5.357587] (udev-worker)[609]: vtcon0: Running command "/usr/bin/systemctl --no-block restart systemd-vconsole-setup.service"
[ 5.357634] (udev-worker)[609]: vtcon0: Starting '/usr/bin/systemctl --no-block restart systemd-vconsole-setup.service'
...
[ 5.680529] systemd[1]: systemd-vconsole-setup.service: Trying to enqueue job systemd-vconsole-setup.service/restart/replace
[ 5.680565] systemd[1]: systemd-vconsole-setup.service: Merged into running job, re-running: systemd-vconsole-setup.service/restart as 557
[ 5.680600] systemd[1]: systemd-vconsole-setup.service: Enqueued job systemd-vconsole-setup.service/restart as 557
...
[ 5.682334] systemd[1]: Received SIGCHLD from PID 744 ((le-setup)).
[ 5.682377] systemd[1]: Child 744 ((le-setup)) died (code=killed, status=15/TERM)
[ 5.682407] systemd[1]: systemd-vconsole-setup.service: Child 744 belongs to systemd-vconsole-setup.service.
[ 5.682436] systemd[1]: systemd-vconsole-setup.service: Main process exited, code=killed, status=15/TERM
[ 5.682471] systemd[1]: systemd-vconsole-setup.service: Failed with result 'signal'.
[ 5.682518] systemd[1]: systemd-vconsole-setup.service: Service will not restart (manual stop)
[ 5.682552] systemd[1]: systemd-vconsole-setup.service: Changed stop-sigterm -> failed
This is expected and not a problem. Let's treat SIGTERM as success so we don't
get this spurious "failure".
"Setup" is a noun, and the expected order is "<adjective> <noun>".
("Set up" is the verb. But we want a noun here, so that we can say
e.g. "Starting Virtual Console Setup".)
Let's make our units more robust to being added to an initrd:
1. systemd-boot-update only makes sense if sd-boot is available in /usr/
to copy into the ESP. This is generally not the case in initrds, and
even if it was, we shouldn't update the ESP from the initrd, but from
the host instead.
2. The rfkill services save/restore rfkill state, but that information
is only available once /var/ is mounted, which generally happens
after the initrd transition.
3. utmp management is partly in /var/, and legacy anyway, hence don't
bother with it in the initrd.
Let's rename the unit to systemd-battery-check.service. We usually want
to name our own unit files like our tools they wrap, in particular if
they are entirely defined by us (i.e. not just wrappers of foreign
concepts)
While we are at it, also hook this in from initrd.target, and order it
against initrd-root-device.target so that it runs before the root device
is possibly written to (i.e. mounted or fsck'ed).
This is heavily inspired by @aafeijoo-suse's PR #28208, but quite
different ;-)
Follow-ups for e3d4148d50.
- add reference to initrd-battery-check.service in man page, and move
its section from 1 to 8,
- add link to man page in help message,
- introduce ERRNO_IS_NO_PLYMOUTH(),
- propagate error in battery_check_send_plymouth_message(),
- rename battery_check_send_plymouth_message() -> plymouth_send_message(),
- return earlier when the first battery level check passed to reduce
indentation,
- fix potential use of invalid fd on battery restored,
- do not use emoji for /dev/console,
- add simple test (mostly for coverity),
etc, etc...
This also merges two arrays units and in_units, and uses dictionary
for declaring units.
This also fixes the condition handling, that previously only two
conditions were handled and rests were ignored.
