Starting the kdbus discussions

[Colin Walters]

On Thu, 2014-01-02 at 14:24 -0500, Colin Walters wrote:
> On Mon, 2013-12-30 at 04:50 +0100, Lennart Poettering wrote:
> 
> > Well, it's not that different from today. On Fedora at least we ship a
> > systemd service file each for all bus-activated system service these days,

[snip some text]

Sorry, I see you replied to this later.  

> Now, there's one big difference when connecting directly to kdbus
> vs. indirectly via the proxy: the old XML policy language is not used
> on
> kdbus directly, the kernel enforces more Unix-like ACLs on service
> names, and will not enforce anything on members/interfaces and so on,
> the way dbus1 allowed that in the XML policy. When connecting to the
> kdbus system bus directly you need to be aware of that, and do your
> own
> access control (which is a lot easier to do though than in dbus1,
> since
> messages carry creds and caps from the sender anyway).

Right, that is a serious concern.  Enough to make me wonder if GLib
should have G_BUS_TYPE_KSYSTEM for example.

But...eww.  It'd be unfortunate to penalize all GDBus users just for the
sake of services which are still installing policy files though =/

Hmm.  Perhaps an alternative is that if *any* files are installed
in /etc/dbus-1/system.d that perform access control, then kdbus is
disabled?  Ugly still.

Another option is to punt to the system builder; GLib would have a
compile-time option --enable-kdbus, and any system builder using
this would take responsibility for ensuring that no GDBus-using clients
are installing DBus XML policy.

Any other ideas?