With this change we'll open the shell's tty right from machined and then
pass it to the transient unit we create. This way we make sure the pty
is opened exactly as long as the transient service is around, and no
longer, and vice versa. This way pty forwarders do not have to deal with
EIO problems due to vhangup, as the pty is open all the time from the
point we set things up to the point where the service goes away.
If set to ~ the working directory is set to the home directory of the
user configured in User=.
This change also exposes the existing switch for the working directory
that allowed making missing working directories non-fatal.
This also changes "machinectl shell" to make use of this to ensure that
the invoked shell is by default in the user's home directory.
Fixes#1268.
off_t is a really weird type as it is usually 64bit these days (at least
in sane programs), but could theoretically be 32bit. We don't support
off_t as 32bit builds though, but still constantly deal with safely
converting from off_t to other types and back for no point.
Hence, never use the type anymore. Always use uint64_t instead. This has
various benefits, including that we can expose these values directly as
D-Bus properties, and also that the values parse the same in all cases.
Now that we get useful error messages from sd-bus for container
connections, let's make use of this and report better errors back to
machined clients.
Fixes#685.
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.
Introduce separate actions for creating login or shell sessions for
the local host or a local container. By default allow local unprivileged
clients to create new login sessions (which is safe, since getty will
ask for username and authentication).
Also, imply login privs from shell privs, as well as shell and login
privs from manage privs.
Some of the operations machined/machinectl implement are also very
useful when applied to the host system (such as machinectl login,
machinectl shell or machinectl status), hence introduce a pseudo-machine
by the name of ".host" in machined that refers to the host system, and
may be used top execute operations on the host system with.
This copies the pseudo-image ".host" machined already implements for
image related commands.
(This commit also adds a PK privilege for opening a PTY in a container,
which was previously not accessible for non-root.)
This new bus call opens an interactive shell in a container. It works
like the existing OpenLogin() call, but does not involve getty, and
instead opens an arbitrary command line.
This is similar to "systemd-run -t -M" but is controlled by a specific
PolicyKit privilege.
To be able to use `systemd-run` or `machinectl login` on a container
that is in a private user namespace, the sub-process must have entered
the user namespace before connecting to the container's D-Bus, otherwise
the UID and GID in the peer credentials are garbage.
So we extend namespace_open and namespace_enter to support UID namespaces,
and we enter the UID namespace in bus_container_connect_{socket,kernel}.
namespace_open will degrade to a no-op if user namespaces are not enabled
in the kernel.
Special handling is required for the setns call in namespace_enter with
a user namespace, since transitioning to your own namespace is forbidden,
as it would result in re-entering your user namespace as root.
Arguably it may be valid to check this at the call site, rather than
inside namespace_enter, but it is less code to do it inside, and if the
intention of calling namespace_enter is to *be* in the target namespace,
rather than to transition to the target namespace, it is a reasonable
approach.
The check for whether the user namespace is the same must happen before
entering namespaces, as we may not be able to access /proc during the
intermediate transition stage.
We can't instead attempt to enter the user namespace and then ignore
the failure from it being the same namespace, since the error code is
not distinct, and we can't compare namespaces while mid-transition.
Absolute paths should be sufficient to prevent funny business,
and while path_is_safe() checks this, it also checks whether the path
contains . or .. components, which while odd, aren't a security risk.
It is no different to return 0 over 1 in the property
callback. It is confusing to return 1 which made me think
1 has a special purpose. This way code is consistent with
the rest of the tree.
./configure --enable/disable-kdbus can be used to set the default
behavior regarding kdbus.
If no kdbus kernel support is available, dbus-dameon will be used.
With --enable-kdbus, the kernel command line option "kdbus=0" can
be used to disable kdbus.
With --disable-kdbus, the kernel command line option "kdbus=1" is
required to enable kdbus support.
XDG refers to X Desktop Group, a former name for freedesktop.org.
This group is responsible for specifications like basedirs,
.desktop files and icon naming, but as far as I know, it has never
tried to redefine basename().
I think these references were meant to say XPG (X/Open Portability
Guide), a precursor of POSIX. POSIX is better-known and less easily
confused with XDG, and is how the basename(3) man page describes
the libgen.h version of basename().
The other version of basename() is glibc-specific and is described
in basename(3) as "the GNU version"; specifically mention that
version, to disambiguate.
If NULL is specified for the bus it is now automatically derived from
the passed in message.
This commit also changes a number of invocations of sd_bus_send() to
make use of this.
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 fixes "machinectl login" on systems configured with --disable-kdbus.
The error was:
machinectl login foo
Failed to get machine PTY: Input/output error
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.
They do not use any functions from libcap directly. The CAP_KILL constant in
use by these files comes from <linux/capability.h> imported through
"missing.h".
Tested that "systemd-machined" builds cleanly and works after this change.
This adds a new bus call to machined that enumerates /var/lib/container
and returns all trees stored in it, distuingishing three types:
- GPT disk images, which are files suffixed with ".gpt"
- directory trees
- btrfs subvolumes
In the long run this should become a full fledged client to networkd
(but not before networkd learns bus support). For now, just pull
interesting data out of networkd, udev, and rtnl and present it to the
user, in a simple but useful output.
Let's settle on a single type for all address family values, even if
UNIX is very inconsitent on the precise type otherwise. Given that
socket() is the primary entrypoint for the sockets API, and that uses
"int", and "int" is relatively simple and generic, we settle on "int"
for this.
