Thread: [dbus-cplusplus-devel] dbus_bus_request_name with bluez

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Hello,

I'm developing the dbus-c++, but I think my problem is dbus specific.
So I ask here.

This is what I do on the terminal:

> dbus-send --system --type=method_call --print-reply --dest=org.bluez / org.bluez.Manager.DefaultAdapter

method return sender=:1.43 -> dest=:1.81 reply_serial=2
   object path "/org/bluez/11832/hci0"

This works well. So I tried the python code:

bus = dbus.SystemBus()

bluez = dbus.Interface(bus.get_object("org.bluez", "/"),
						"org.bluez.Manager")

print "DefaultAdapter: " + bluez.DefaultAdapter ()

This prints:

DefaultAdapter: /org/bluez/11832/hci0

Also working, so I tested it with dbus-c++ and I get this error:

> ./bluephone 
terminate called after throwing an instance of 'DBus::Error'
  what():  Connection ":1.83" is not allowed to own the service "org.bluez" due 
  to security policies in the configuration file
Aborted

So I debugged into the library and see this C code:

void Connection::request_name(const char *name, int flags)
{
	InternalError e;

	debug_log("%s: registering bus name %s", unique_name(), name);

	int ret = dbus_bus_request_name(_pvt->conn, name, flags, e);

        if (ret == -1)
        {
	       if (e) throw Error(e);
        }

	if (name)
	{
		_pvt->names.push_back(name);
		std::string match = "destination='" + _pvt->names.back() + "'";
		add_match(match.c_str());
	}
}

Debugger says:

flags = 0
name = "org.bluez"
ret = -1

So it throws the Error in this case. If I comment out the Exception throw
than my example works without problems. This is really strange and gets me 
to some questions:

* Did I a mistake?

* Why is the dbus-send working?

* Why is the Python example working

* Why does DBus simply give my application access to the liked service
  only by ignoring the error handling? Isn't this a little insecure?

BTW: I just found out if I start my application as root it also works
with enabled exception handling. Have I found a security hole (at least
in dbus-python and dbus-send)?

bluez-4.12-0ubuntu5

regards
Andreas