In preparation for reusing the image dissector in the GPT auto-discovery
logic, only optionally fail the dissection when we can't identify a root
partition.
In the GPT auto-discovery we are completely fine with any kind of root,
given that we run when it is already mounted and all we do is find some
additional auxiliary partitions on the same disk.
This is useful for reusing the dissector logic in the gpt-auto-discovery logic:
there we really don't want to use MBR or naked file systems as root device.
This adds support for discovering and making use of properly tagged dm-verity
data integrity partitions. This extends both systemd-nspawn and systemd-dissect
with a new --root-hash= switch that takes the root hash to use for the root
partition, and is otherwise fully automatic.
Verity partitions are discovered automatically by GPT table type UUIDs, as
listed in
https://www.freedesktop.org/wiki/Specifications/DiscoverablePartitionsSpec/
(which I updated prior to this change, to include new UUIDs for this purpose.
mkosi with https://github.com/systemd/mkosi/pull/39 applied may generate images
that carry the necessary integrity data. With that PR and this commit, the
following simply lines suffice to boot up an integrity-protected container image:
```
# mkdir test
# cd test
# mkosi --verity
# systemd-nspawn -i ./image.raw -bn
```
Note that mkosi writes the image file to "image.raw" next to a a file
"image.roothash" that contains the root hash. systemd-nspawn will look for that
file and use it if it exists, in case --root-hash= is not specified explicitly.
This adds support to the image dissector to deal with encrypted images (only
LUKS). Given that we now have a neatly isolated image dissector codebase, let's
add a new feature to it: support for automatically dealing with encrypted
images. This is then exposed in systemd-dissect and nspawn.
It's pretty basic: only support for passphrase-based encryption.
In order to ensure that "systemd-dissect --mount" results in mount points whose
backing LUKS DM devices are cleaned up automatically we use the DM_DEV_REMOVE
ioctl() directly on the device (in DM_DEFERRED_REMOVE mode). libgcryptsetup at
the moment doesn't provide a proper API for this. Thankfully, the ioctl() API
is pretty easy to use.
This adds a bus call GetImageOSRelease() to the Manager interface that
retrieves the /etc/os-release file of a machine image. It matches the existing
GetMachineOSRelease() call, however operates on a disk image rather than a
running container.
The backend for this call on .raw images is implemented via the generalized
image dissector, which makes this scheme relatively easy to implement.
This is a follow-up to 5d2036b5f3, and also makes
the "machinectl clean" verb asynchronous, after all it's little more than a
series of image removals.
The changes required to make this happen are a bit more comprehensive as we
need to pass information about deleted images back to the client, as well as
information about the image we failed on if we failed on one. Hence, create a
temporary file in /tmp, serialize that data into, and read it from the parent
after the operation is complete.
If we remove a directory image (i.e. not a btrfs snapshot) then things might
get quite expensive, hence run this asynchronous in a forked off process, too.
Let's make sigkill_wait() take a normal pid_t, and add sigkill_waitp() that
takes a pointer (which is useful for usage in _cleanup_), following the usual
logic we have for this.
Cloning an image can be slow, if the image is not on a btrfs subvolume, hence
let's make sure we do this asynchronously in a child process, so that machined
isn't blocked as long as we process the client request.
This adds a new, generic "Operation" object to machined, that is used to track
these kind of background processes.
This is inspired by the MachineOperation object that already exists to make
copy operations asynchronous. A later patch will rework the MachineOperation
logic to use the generic Operation instead.
Fixes: #2060
(Of course, in the long run, we should probably add a copy-based fall-back. But
given how slow that is, this probably requires some asynchronous forking logic
like the CopyFrom() and CopyTo() method calls already implement.)
Extra details for an action can be supplied when calling polkit's
CheckAuthorization method. Details are a list of key/value string pairs.
Custom policy can use these details when making authorization decisions.
This should simplify the prototype a bit. The bus parameter is redundant
in most cases, and in the few where it matters it can be derived from
the message via sd_bus_message_get_bus().
This patch removes includes that are not used. The removals were found with
include-what-you-use which checks if any of the symbols from a header is
in use.
Also, allow clients to alter their own objects without any further
priviliges. i.e. this allows clients to kill and lock their own sessions
without involving PK.
