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XDG-DBUS-PROXY(1)		 User Commands		     XDG-DBUS-PROXY(1)

NAME
       xdg-dbus-proxy -	D-Bus proxy

SYNOPSIS

       xdg-dbus-proxy [OPTION...] [ADDRESS PATH	[OPTION...]...]

DESCRIPTION
       xdg-dbus-proxy is a filtering proxy for D-Bus connections. Its
       arguments are one or more ADDRESS-PATH pairs specifying the buses to
       proxy, with options that	specify	what filtering to apply.

   Basic Operation
       The proxy listens to the	unix domain socket at PATH, and	for each
       client that connects to the socket, it opens up a new connection	to the
       specified D-Bus ADDRESS (typically the session bus) and forwards	data
       between the two.	During the authentication phase	all data is forwarded
       as received, and	additionally for the first 1 byte zero we also send
       the proxy credentials to	the bus.

       Once the	connection is authenticated there are two modes, filtered and
       unfiltered. In the unfiltered mode all messages are sent	on as they are
       received. In the	filtering mode policy is applied to determine which
       messages	to allow, and which to drop.

       Filtering is applied only to outgoing signals and method	calls and
       incoming	broadcast signals. All replies (errors or method returns) are
       allowed once for	an outstanding method call, and	never otherwise.

       If a client ever	receives a message from	another	peer on	the bus, the
       senders unique name is made visible, so the client can track caller
       lifetimes via NameOwnerChanged signals. If a client calls a method on
       or receives a broadcast signal from a name (even	if filtered to some
       subset of paths or interfaces), that names basic	policy is considered
       to be (at least)	TALK, from then	on.

   Policy
       The policy for the filtering consists of	a mapping from well-known
       names to	a policy that is either	SEE, TALK or OWN. The default initial
       policy is that the the user is only allowed to TALK to the bus itself
       (org.freedesktop.DBus, or no destination	specified), and	TALK to	its
       own unique ID. All other	clients	are invisible.

       Here is a description of	the policy levels (each	level implies the ones
       before it):

       SEE
	   The name/ID is visible in the ListNames reply

	   The name/ID is visible in the ListActivatableNames reply

	   You can call	GetNameOwner on	the name

	   You can call	NameHasOwner on	the name

	   You see NameOwnerChanged signals on the name

	   You see NameOwnerChanged signals on the ID when the client
	   disconnects

	   You can call	the GetXXX methods on the name/ID to get e.g. the peer
	   pid

	   You get AccessDenied	rather than NameHasNoOwner when	sending
	   messages to the name/ID

       TALK
	   You can send	any method calls and signals to	the name/ID

	   You will receive broadcast signals from the name/ID (if you have a
	   match rule for them)

	   You can call	StartServiceByName on the name

       OWN
	   You are allowed to call RequestName/ReleaseName/ListQueuedOwners on
	   the name

       Policy is specified with	the --see, --talk and --own options. The
       well-known names	in these options can have a '.*' suffix. A name	of
       "org.foo.*" matches "org.foo", org.foo.bar", and	"org.foo.bar.gazonk",
       but not "org.foobar".

       Polices are specified for well-known names, but they also affect	the
       owner of	that name, so that the policy for a unique ID is the union of
       the polices for all the names it	owns. For technical reasons, the
       policy for a unique name	is "sticky", in	that the highest policy
       granted by a once-owned name is kept, even when the client releases
       that name. This is impossible to	avoid in a race-free way in a proxy.
       But it is rarely	a problem in practice, as few clients release names
       and stay	on the bus.

       In addition to the basic	SEE/TALK/OWN policy, it	is possible to specify
       more complicated	rules about what method	calls can be made on and what
       broadcast signals can be	received from well-known names.	A rule can
       restrict	the allowed calls/signals to a specific	object path or a
       subtree of object paths,	and it can restrict the	allowed	interface down
       to an individual	method or signal name.

       Rules are specified with	the --call and --broadcast options. The	RULE
       in these	options	determines what	interfaces, methods and	object paths
       are allowed. It must be of the form [METHOD][@PATH], where METHOD can
       be either '*' or	a D-Bus	interface, possible with a '.*'	suffix,	or a
       fully-qualified method name, and	PATH is	a D-Bus	object path, possible
       with a '/*' suffix.

OPTIONS
       When options are	used multiple times, the last option wins, unless
       otherwise specified.

       General options:

       --help
	   Print help and exit

       --version
	   Print version

       --fd=FD
	   Write to FD when the	proxies	are ready, and stop when it is closed.

       --args=FD
	   Parse nul-separated arguments from the given	file descriptor. This
	   option can be used multiple times to	parse options from multiple
	   sources.

       Proxy Options:

       These options can only be used after an ADDRESS and apply to the	proxy
       for that	address.

       --filter
	   Enable filtering

       --log
	   Turn	on logging

       --sloppy-names
	   Make	all unique names visible.

       --see=NAME
	   Set the SEE policy for the given name.

       --talk=NAME
	   Set the TALK	policy for the given name.

       --own=NAME
	   Set the OWN policy for the given name.

       --call=NAME=RULE
	   Set a rule for calls	on the given name.

       --broadcast=NAME=RULE
	   Set a rule for broadcast signals from the given name.

EXAMPLES
       $ xdg-dbus-proxy	--fd=26	unix:path=/run/usr/1000/bus
       /run/usr/1000/.dbus-proxy/session-bus-proxy --filter
       --own=org.gnome.ghex.* --talk=ca.desrt.dconf
       --call=org.freedesktop.portal.*=*
       --broadcast=org.freedesktop.portal.*=@/org/freedesktop/portal/*

flatpak							     XDG-DBUS-PROXY(1)

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