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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  op-
     tions 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 un-
     filtered. In the unfiltered mode all messages are sent on as they	are  re-
     ceived. 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 life-
     times via NameOwnerChanged signals. If a client calls a method  on  or  re-
     ceives  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.freedesk-
     top.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 be-
     fore 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  po-
     lices  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 prac-
     tice, 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 re-
     strict 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 individ-
     ual 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  al-
     lowed.  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  other-
     wise 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 op-
	 tion 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.*=*	--broad-
     cast=org.freedesktop.portal.*=@/org/freedesktop/portal/*

flatpak 						       XDG-DBUS-PROXY(1)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=xdg-dbus-proxy&sektion=1&manpath=FreeBSD+Ports+15.1.quarterly>

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