This commit includes adding introduce manager_get_machine_by_pidref() as a replacement for manager_get_machine_by_pid()
and moving surrounding code to utilise PidRef.
These operations might require slow I/O, and thus might block PID1's main
loop for an undeterminated amount of time. Instead of performing them
inline, fork a worker process and stash away the D-Bus message, and reply
once we get a SIGCHILD indicating they have completed. That way we don't
break compatibility and callers can continue to rely on the fact that when
they get the method reply the operation either succeeded or failed.
To keep backward compatibility, unlike reload control processes, these
are ran inside init.scope and not the target cgroup. Unlike ExecReload,
this is under our control and is not defined by the unit. This is necessary
because previously the operation also wasn't ran from the target cgroup,
so suddenly forking a copy-on-write copy of pid1 into the target cgroup
will make memory usage spike, and if there is a MemoryMax= or MemoryHigh=
set and the cgroup is already close to the limit, it will cause an OOM
kill, where previously it would have worked fine.
Also adds three properties:
- VsockCid: the VSOCK CID of the VM
- SshAddress: the address of the VM in a format SSH can connect to
- SshPrivateKeyPath: the path to the SSH private key to use to connect
to the VM.
GetMachineSSHInfo is essentially a convenience method to query both the
SshAddress and SshPrivateKeyPath properties at once.
This simplifies bus_verify_polkit_async() and related calls quite a bit:
1. This removes any support for authentication-by-Linux-capability. This
is ultimately a kdbus leftover: with classic AF_UNIX transports we
cannot authenticate by capabilities securely (because we cannot
acquire it from the peer without races), hence we never actually did.
Since the necessary kernel work didn't materialize in the last 10y,
and is unlikely to be added, let's just kill this context. We cannot
quite remove the caps stuff from sd-bus for API compat, but for our
polkit logic let's kill it.
2. The "good_uid" and "interactive" params are only necessary in very
few cases, hence let's move them to a new call
bus_verify_polkit_async_full() and make bus_verify_polkit_async() a
wrapper around it without those two parameters.
This also fixes a bunch of wrong uses of the "interactive" bool. The
bool makes no sense today as the ALLOW_INTERACTIVE_AUTHORIZATION field
in the D-Bus message header replaces it fully. We only need it to
implement method calls we introduced prior to that header field becoming
available in D-Bus. And it should only be used on such old method calls,
and otherwise always be set to false.
This does not change behaviour in any way. Just simplifies stuff.
Fixes: #21586
Sometimes it makes sense to hard kill a client if we die. Let's hence
add a third FORK_DEATHSIG flag for this purpose: FORK_DEATHSIG_SIGKILL.
To make things less confusing this also renames FORK_DEATHSIG to
FORK_DEATHSIG_SIGTERM to make clear it sends SIGTERM. We already had
FORK_DEATHSIG_SIGINT, hence this makes things nicely symmetric.
A bunch of users are switched over for FORK_DEATHSIG_SIGKILL where we
know it's safe to abort things abruptly. This should make some kernel
cases more robust, since we cannot get confused by signal masks or such.
While we are at it, also fix a bunch of bugs where we didn't take
FORK_DEATHSIG_SIGINT into account in safe_fork()
We use it for more than just pipe() arrays. For example also for
socketpair(). Hence let's give it a generic name.
Also add EBADF_TRIPLET to mirror this for things like
stdin/stdout/stderr arrays, which we use a bunch of times.
This is preparation for #28891, which adds a bunch more helpers around
"struct iovec", at which point this really deserves its own .c/.h file.
The idea is that we sooner or later can consider "struct iovec" as an
entirely generic mechanism to reference some binary blob, and is the
go-to type for this purpose whenever we need one.
The subvolumes set is a set of source inodes similar to how the
denylist hashmap contains source inodes as keys. It indicates
directories in the source tree that should become subvolumes in
the target tree.
The article "a" goes before consonant sounds and "an" goes before vowel
sounds. This commit changes an to a for UKI, UDP, UTF-8, URL, UUID, U-Label, UI
and USB, since they start with the sound /ˌjuː/.
In various tools and services we have a per-system and per-user concept.
So far we sometimes used a boolean indicating whether we are in system
mode, or a reversed boolean indicating whether we are in user mode, or
the LookupScope enum used by the lookup path logic.
Let's address that, in introduce a common enum for this, we can use all
across the board.
This is mostly just search/replace, no actual code changes.
Pass the joined arguments to polkit as command_line property like
pkexec does. Obviously not exactly perfect as it lacks quoting. Good
enough for polkit rules to check whether a program was called with
or without arguments though.
-1 was used everywhere, but -EBADF or -EBADFD started being used in various
places. Let's make things consistent in the new style.
Note that there are two candidates:
EBADF 9 Bad file descriptor
EBADFD 77 File descriptor in bad state
Since we're initializating the fd, we're just assigning a value that means
"no fd yet", so it's just a bad file descriptor, and the first errno fits
better. If instead we had a valid file descriptor that became invalid because
of some operation or state change, the other errno would fit better.
In some places, initialization is dropped if unnecessary.
machine: Add APIs CopyTo[Machine]WithFlags + CopyFrom[Machine]WithFlags
- Same API to those without `WithFlags` (except this can take flags)
- Initially, only a flag to allow replacing a file if it already exists
* machine: update to use new-style sd-bus macros
Replace old SD_BUS_METHOD_WITH_NAMES and SD_BUS_SIGNAL_WITH_NAMES macros to
the new SD_BUS_METHOD_WITH_ARGS and SD_BUS_SIGNAL_WITH_ARGS macros.
Meson test, mkosi test image and running machinectl after build returned
no error. But since I don't have any virtual machines or containers, I'm not
sure how to test the changes thoroughly.
Let's define two helpers strdupa_safe() + strndupa_safe() which do the
same as their non-safe counterparts, except that they abort if called
with allocations larger than ALLOCA_MAX.
This should ensure that all our alloca() based allocations are subject
to this limit.
afaics glibc offers three alloca() based APIs: alloca() itself,
strndupa() + strdupa(). With this we have now replacements for all of
them, that take the limit into account.
Daan De Meyer
Yu Watanabe
Ivan Kruglov
Lennart Poettering
Mike Yuan
Luca Boccassi
Zbigniew Jędrzejewski-Szmek
Sam Leonard
Joerg Behrmann
Ludwig Nussel
David Tardon
Frantisek Sumsal
Alexander Wilson
Amarjargal
Luca Boccassi