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diff --git a/src/3rd_party/dbus-1.7.8/doc/dbus-daemon.1.xml.in b/src/3rd_party/dbus-1.7.8/doc/dbus-daemon.1.xml.in deleted file mode 100644 index 1a1e42cd2c..0000000000 --- a/src/3rd_party/dbus-1.7.8/doc/dbus-daemon.1.xml.in +++ /dev/null @@ -1,926 +0,0 @@ -<?xml version="1.0" encoding="ISO-8859-1"?> -<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN" - "http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd"> -<refentry id='dbusdaemon1'> - -<!-- dbus\-daemon manual page. - Copyright (C) 2003,2008 Red Hat, Inc. --> - -<refmeta> -<refentrytitle>dbus-daemon</refentrytitle> -<manvolnum>1</manvolnum> -<refmiscinfo class="manual">User Commands</refmiscinfo> -<refmiscinfo class="source">D-Bus</refmiscinfo> -<refmiscinfo class="version">@DBUS_VERSION@</refmiscinfo> -</refmeta> -<refnamediv> -<refname>dbus-daemon</refname> -<refpurpose>Message bus daemon</refpurpose> -</refnamediv> -<!-- body begins here --> -<refsynopsisdiv id='synopsis'> -<cmdsynopsis> - <command>dbus-daemon</command></cmdsynopsis> -<cmdsynopsis> - <command>dbus-daemon</command> <arg choice='opt'>--version </arg> - <arg choice='opt'>--session </arg> - <arg choice='opt'>--system </arg> - <arg choice='opt'>--config-file=<replaceable>FILE</replaceable></arg> - <arg choice='opt'><arg choice='plain'>--print-address </arg><arg choice='opt'><replaceable>=DESCRIPTOR</replaceable></arg></arg> - <arg choice='opt'><arg choice='plain'>--print-pid </arg><arg choice='opt'><replaceable>=DESCRIPTOR</replaceable></arg></arg> - <arg choice='opt'>--fork </arg> - <sbr/> -</cmdsynopsis> -</refsynopsisdiv> - - -<refsect1 id='description'><title>DESCRIPTION</title> -<para><command>dbus-daemon</command> is the D-Bus message bus daemon. See -<ulink url='http://www.freedesktop.org/software/dbus/'>http://www.freedesktop.org/software/dbus/</ulink> for more information about -the big picture. D-Bus is first a library that provides one-to-one -communication between any two applications; <command>dbus-daemon</command> is an -application that uses this library to implement a message bus -daemon. Multiple programs connect to the message bus daemon and can -exchange messages with one another.</para> - -<para>There are two standard message bus instances: the systemwide message bus -(installed on many systems as the "messagebus" init service) and the -per-user-login-session message bus (started each time a user logs in). -<command>dbus-daemon</command> is used for both of these instances, but with -a different configuration file.</para> - -<para>The --session option is equivalent to -"--config-file=@EXPANDED_SYSCONFDIR@/dbus-1/session.conf" and the --system -option is equivalent to -"--config-file=@EXPANDED_SYSCONFDIR@/dbus-1/system.conf". By creating -additional configuration files and using the --config-file option, -additional special-purpose message bus daemons could be created.</para> - -<para>The systemwide daemon is normally launched by an init script, -standardly called simply "messagebus".</para> - -<para>The systemwide daemon is largely used for broadcasting system events, -such as changes to the printer queue, or adding/removing devices.</para> - -<para>The per-session daemon is used for various interprocess communication -among desktop applications (however, it is not tied to X or the GUI -in any way).</para> - -<para>SIGHUP will cause the D-Bus daemon to PARTIALLY reload its -configuration file and to flush its user/group information caches. Some -configuration changes would require kicking all apps off the bus; so they will -only take effect if you restart the daemon. Policy changes should take effect -with SIGHUP.</para> - -</refsect1> - -<refsect1 id='options'><title>OPTIONS</title> -<para>The following options are supported:</para> -<variablelist remap='TP'> - <varlistentry> - <term><option>--config-file=FILE</option></term> - <listitem> -<para>Use the given configuration file.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>--fork</option></term> - <listitem> -<para>Force the message bus to fork and become a daemon, even if -the configuration file does not specify that it should. -In most contexts the configuration file already gets this -right, though. This option is not supported on Windows.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>--nofork</option></term> - <listitem> - <para>Force the message bus not to fork and become a daemon, even if - the configuration file specifies that it should. On Windows, - the dbus-daemon never forks, so this option is allowed but does - nothing.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>--print-address[=DESCRIPTOR]</option></term> - <listitem> -<para>Print the address of the message bus to standard output, or -to the given file descriptor. This is used by programs that -launch the message bus.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>--print-pid[=DESCRIPTOR]</option></term> - <listitem> -<para>Print the process ID of the message bus to standard output, or -to the given file descriptor. This is used by programs that -launch the message bus.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>--session</option></term> - <listitem> -<para>Use the standard configuration file for the per-login-session message -bus.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>--system</option></term> - <listitem> -<para>Use the standard configuration file for the systemwide message bus.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>--version</option></term> - <listitem> -<para>Print the version of the daemon.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>--introspect</option></term> - <listitem> -<para>Print the introspection information for all D-Bus internal interfaces.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>--address[=ADDRESS]</option></term> - <listitem> -<para>Set the address to listen on. This option overrides the address -configured in the configuration file.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>--systemd-activation</option></term> - <listitem> -<para>Enable systemd-style service activation. Only useful in conjunction -with the systemd system and session manager on Linux.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>--nopidfile</option></term> - <listitem> -<para>Don't write a PID file even if one is configured in the configuration -files.</para> - - </listitem> - </varlistentry> -</variablelist> -</refsect1> - -<refsect1 id='configuration_file'><title>CONFIGURATION FILE</title> -<para>A message bus daemon has a configuration file that specializes it -for a particular application. For example, one configuration -file might set up the message bus to be a systemwide message bus, -while another might set it up to be a per-user-login-session bus.</para> - -<para>The configuration file also establishes resource limits, security -parameters, and so forth.</para> - -<para>The configuration file is not part of any interoperability -specification and its backward compatibility is not guaranteed; this -document is documentation, not specification.</para> - -<para>The standard systemwide and per-session message bus setups are -configured in the files "@EXPANDED_SYSCONFDIR@/dbus-1/system.conf" and -"@EXPANDED_SYSCONFDIR@/dbus-1/session.conf". These files normally -<include> a system-local.conf or session-local.conf; you can put local -overrides in those files to avoid modifying the primary configuration -files.</para> - - -<para>The configuration file is an XML document. It must have the following -doctype declaration:</para> -<literallayout remap='.nf'> - - <!DOCTYPE busconfig PUBLIC "-//freedesktop//DTD D-Bus Bus Configuration 1.0//EN" - "<ulink url='http://www.freedesktop.org/standards/dbus/1.0/busconfig.dtd'>http://www.freedesktop.org/standards/dbus/1.0/busconfig.dtd</ulink>"> - -</literallayout> <!-- .fi --> - - -<para>The following elements may be present in the configuration file.</para> - -<itemizedlist remap='TP'> - - <listitem><para><emphasis remap='I'><busconfig></emphasis></para></listitem> - - -</itemizedlist> - -<para>Root element.</para> - -<itemizedlist remap='TP'> - - <listitem><para><emphasis remap='I'><type></emphasis></para></listitem> - - -</itemizedlist> - -<para>The well-known type of the message bus. Currently known values are -"system" and "session"; if other values are set, they should be -either added to the D-Bus specification, or namespaced. The last -<type> element "wins" (previous values are ignored). This element -only controls which message bus specific environment variables are -set in activated clients. Most of the policy that distinguishes a -session bus from the system bus is controlled from the other elements -in the configuration file.</para> - - -<para>If the well-known type of the message bus is "session", then the -DBUS_STARTER_BUS_TYPE environment variable will be set to "session" -and the DBUS_SESSION_BUS_ADDRESS environment variable will be set -to the address of the session bus. Likewise, if the type of the -message bus is "system", then the DBUS_STARTER_BUS_TYPE environment -variable will be set to "system" and the DBUS_SESSION_BUS_ADDRESS -environment variable will be set to the address of the system bus -(which is normally well known anyway).</para> - - -<para>Example: <type>session</type></para> - -<itemizedlist remap='TP'> - - <listitem><para><emphasis remap='I'><include></emphasis></para></listitem> - - -</itemizedlist> - -<para>Include a file <include>filename.conf</include> at this point. If the -filename is relative, it is located relative to the configuration file -doing the including.</para> - - -<para><include> has an optional attribute "ignore_missing=(yes|no)" -which defaults to "no" if not provided. This attribute -controls whether it's a fatal error for the included file -to be absent.</para> - -<itemizedlist remap='TP'> - - <listitem><para><emphasis remap='I'><includedir></emphasis></para></listitem> - - -</itemizedlist> - -<para>Include all files in <includedir>foo.d</includedir> at this -point. Files in the directory are included in undefined order. -Only files ending in ".conf" are included.</para> - - -<para>This is intended to allow extension of the system bus by particular -packages. For example, if CUPS wants to be able to send out -notification of printer queue changes, it could install a file to -@EXPANDED_SYSCONFDIR@/dbus-1/system.d that allowed all apps to receive -this message and allowed the printer daemon user to send it.</para> - -<itemizedlist remap='TP'> - - <listitem><para><emphasis remap='I'><user></emphasis></para></listitem> - - -</itemizedlist> - -<para>The user account the daemon should run as, as either a username or a -UID. If the daemon cannot change to this UID on startup, it will exit. -If this element is not present, the daemon will not change or care -about its UID.</para> - - -<para>The last <user> entry in the file "wins", the others are ignored.</para> - - -<para>The user is changed after the bus has completed initialization. So -sockets etc. will be created before changing user, but no data will be -read from clients before changing user. This means that sockets -and PID files can be created in a location that requires root -privileges for writing.</para> - -<itemizedlist remap='TP'> - - <listitem><para><emphasis remap='I'><fork></emphasis></para></listitem> - - -</itemizedlist> - -<para>If present, the bus daemon becomes a real daemon (forks -into the background, etc.). This is generally used -rather than the --fork command line option.</para> - -<itemizedlist remap='TP'> - - <listitem><para><emphasis remap='I'><keep_umask></emphasis></para></listitem> - - -</itemizedlist> - -<para>If present, the bus daemon keeps its original umask when forking. -This may be useful to avoid affecting the behavior of child processes.</para> - -<itemizedlist remap='TP'> - - <listitem><para><emphasis remap='I'><syslog></emphasis></para></listitem> - - -</itemizedlist> - -<para>If present, the bus daemon will log to syslog.</para> - -<itemizedlist remap='TP'> - - <listitem><para><emphasis remap='I'><pidfile></emphasis></para></listitem> - - -</itemizedlist> - -<para>If present, the bus daemon will write its pid to the specified file. -The --nopidfile command-line option takes precedence over this setting.</para> - -<itemizedlist remap='TP'> - - <listitem><para><emphasis remap='I'><allow_anonymous></emphasis></para></listitem> - - -</itemizedlist> - -<para>If present, connections that authenticated using the ANONYMOUS -mechanism will be authorized to connect. This option has no practical -effect unless the ANONYMOUS mechanism has also been enabled using the -<emphasis remap='I'><auth></emphasis> element, described below.</para> - -<itemizedlist remap='TP'> - - <listitem><para><emphasis remap='I'><listen></emphasis></para></listitem> - - -</itemizedlist> - -<para>Add an address that the bus should listen on. The -address is in the standard D-Bus format that contains -a transport name plus possible parameters/options.</para> - - -<para>Example: <listen>unix:path=/tmp/foo</listen></para> - - -<para>Example: <listen>tcp:host=localhost,port=1234</listen></para> - - -<para>If there are multiple <listen> elements, then the bus listens -on multiple addresses. The bus will pass its address to -started services or other interested parties with -the last address given in <listen> first. That is, -apps will try to connect to the last <listen> address first.</para> - - -<para>tcp sockets can accept IPv4 addresses, IPv6 addresses or hostnames. -If a hostname resolves to multiple addresses, the server will bind -to all of them. The family=ipv4 or family=ipv6 options can be used -to force it to bind to a subset of addresses</para> - - -<para>Example: <listen>tcp:host=localhost,port=0,family=ipv4</listen></para> - - -<para>A special case is using a port number of zero (or omitting the port), -which means to choose an available port selected by the operating -system. The port number chosen can be obtained with the ---print-address command line parameter and will be present in other -cases where the server reports its own address, such as when -DBUS_SESSION_BUS_ADDRESS is set.</para> - - -<para>Example: <listen>tcp:host=localhost,port=0</listen></para> - - -<para>tcp addresses also allow a bind=hostname option, which will override -the host option specifying what address to bind to, without changing -the address reported by the bus. The bind option can also take a -special name '*' to cause the bus to listen on all local address -(INADDR_ANY). The specified host should be a valid name of the local -machine or weird stuff will happen.</para> - - -<para>Example: <listen>tcp:host=localhost,bind=*,port=0</listen></para> - -<itemizedlist remap='TP'> - - <listitem><para><emphasis remap='I'><auth></emphasis></para></listitem> - - -</itemizedlist> - -<para>Lists permitted authorization mechanisms. If this element doesn't -exist, then all known mechanisms are allowed. If there are multiple -<auth> elements, all the listed mechanisms are allowed. The order in -which mechanisms are listed is not meaningful.</para> - - -<para>Example: <auth>EXTERNAL</auth></para> - - -<para>Example: <auth>DBUS_COOKIE_SHA1</auth></para> - -<itemizedlist remap='TP'> - - <listitem><para><emphasis remap='I'><servicedir></emphasis></para></listitem> - - -</itemizedlist> - -<para>Adds a directory to scan for .service files. Directories are -scanned starting with the first to appear in the config file -(the first .service file found that provides a particular -service will be used).</para> - - -<para>Service files tell the bus how to automatically start a program. -They are primarily used with the per-user-session bus, -not the systemwide bus.</para> - -<itemizedlist remap='TP'> - - <listitem><para><emphasis remap='I'><standard_session_servicedirs/></emphasis></para></listitem> - - -</itemizedlist> - -<para><standard_session_servicedirs/> is equivalent to specifying a series -of <servicedir/> elements for each of the data directories in the "XDG -Base Directory Specification" with the subdirectory "dbus-1/services", -so for example "/usr/share/dbus-1/services" would be among the -directories searched.</para> - - -<para>The "XDG Base Directory Specification" can be found at -<ulink url='http://freedesktop.org/wiki/Standards/basedir-spec'>http://freedesktop.org/wiki/Standards/basedir-spec</ulink> if it hasn't moved, -otherwise try your favorite search engine.</para> - - -<para>The <standard_session_servicedirs/> option is only relevant to the -per-user-session bus daemon defined in -@EXPANDED_SYSCONFDIR@/dbus-1/session.conf. Putting it in any other -configuration file would probably be nonsense.</para> - -<itemizedlist remap='TP'> - - <listitem><para><emphasis remap='I'><standard_system_servicedirs/></emphasis></para></listitem> - - -</itemizedlist> - -<para><standard_system_servicedirs/> specifies the standard system-wide -activation directories that should be searched for service files. -This option defaults to @EXPANDED_DATADIR@/dbus-1/system-services.</para> - - -<para>The <standard_system_servicedirs/> option is only relevant to the -per-system bus daemon defined in -@EXPANDED_SYSCONFDIR@/dbus-1/system.conf. Putting it in any other -configuration file would probably be nonsense.</para> - -<itemizedlist remap='TP'> - - <listitem><para><emphasis remap='I'><servicehelper/></emphasis></para></listitem> - - -</itemizedlist> - -<para><servicehelper/> specifies the setuid helper that is used to launch -system daemons with an alternate user. Typically this should be -the dbus-daemon-launch-helper executable in located in libexec.</para> - - -<para>The <servicehelper/> option is only relevant to the per-system bus daemon -defined in @EXPANDED_SYSCONFDIR@/dbus-1/system.conf. Putting it in any other -configuration file would probably be nonsense.</para> - -<itemizedlist remap='TP'> - - <listitem><para><emphasis remap='I'><limit></emphasis></para></listitem> - - -</itemizedlist> - -<para><limit> establishes a resource limit. For example:</para> -<literallayout remap='.nf'> - <limit name="max_message_size">64</limit> - <limit name="max_completed_connections">512</limit> -</literallayout> <!-- .fi --> - - -<para>The name attribute is mandatory. -Available limit names are:</para> -<literallayout remap='.nf'> - "max_incoming_bytes" : total size in bytes of messages - incoming from a single connection - "max_incoming_unix_fds" : total number of unix fds of messages - incoming from a single connection - "max_outgoing_bytes" : total size in bytes of messages - queued up for a single connection - "max_outgoing_unix_fds" : total number of unix fds of messages - queued up for a single connection - "max_message_size" : max size of a single message in - bytes - "max_message_unix_fds" : max unix fds of a single message - "service_start_timeout" : milliseconds (thousandths) until - a started service has to connect - "auth_timeout" : milliseconds (thousandths) a - connection is given to - authenticate - "max_completed_connections" : max number of authenticated connections - "max_incomplete_connections" : max number of unauthenticated - connections - "max_connections_per_user" : max number of completed connections from - the same user - "max_pending_service_starts" : max number of service launches in - progress at the same time - "max_names_per_connection" : max number of names a single - connection can own - "max_match_rules_per_connection": max number of match rules for a single - connection - "max_replies_per_connection" : max number of pending method - replies per connection - (number of calls-in-progress) - "reply_timeout" : milliseconds (thousandths) - until a method call times out -</literallayout> <!-- .fi --> - - -<para>The max incoming/outgoing queue sizes allow a new message to be queued -if one byte remains below the max. So you can in fact exceed the max -by max_message_size.</para> - - -<para>max_completed_connections divided by max_connections_per_user is the -number of users that can work together to denial-of-service all other users by using -up all connections on the systemwide bus.</para> - - -<para>Limits are normally only of interest on the systemwide bus, not the user session -buses.</para> - -<itemizedlist remap='TP'> - - <listitem><para><emphasis remap='I'><policy></emphasis></para></listitem> - - -</itemizedlist> - -<para>The <policy> element defines a security policy to be applied to a particular -set of connections to the bus. A policy is made up of -<allow> and <deny> elements. Policies are normally used with the systemwide bus; -they are analogous to a firewall in that they allow expected traffic -and prevent unexpected traffic.</para> - - -<para>Currently, the system bus has a default-deny policy for sending method calls -and owning bus names. Everything else, in particular reply messages, receive -checks, and signals has a default allow policy.</para> - - -<para>In general, it is best to keep system services as small, targeted programs which -run in their own process and provide a single bus name. Then, all that is needed -is an <allow> rule for the "own" permission to let the process claim the bus -name, and a "send_destination" rule to allow traffic from some or all uids to -your service.</para> - - -<para>The <policy> element has one of four attributes:</para> -<literallayout remap='.nf'> - context="(default|mandatory)" - at_console="(true|false)" - user="username or userid" - group="group name or gid" -</literallayout> <!-- .fi --> - - -<para>Policies are applied to a connection as follows:</para> -<literallayout remap='.nf'> - - all context="default" policies are applied - - all group="connection's user's group" policies are applied - in undefined order - - all user="connection's auth user" policies are applied - in undefined order - - all at_console="true" policies are applied - - all at_console="false" policies are applied - - all context="mandatory" policies are applied -</literallayout> <!-- .fi --> - - -<para>Policies applied later will override those applied earlier, -when the policies overlap. Multiple policies with the same -user/group/context are applied in the order they appear -in the config file.</para> - -<variablelist remap='TP'> - <varlistentry> - <term><emphasis remap='I'><deny></emphasis></term> - <listitem> -<para><emphasis remap='I'><allow></emphasis></para> - - </listitem> - </varlistentry> -</variablelist> - -<para>A <deny> element appears below a <policy> element and prohibits some -action. The <allow> element makes an exception to previous <deny> -statements, and works just like <deny> but with the inverse meaning.</para> - - -<para>The possible attributes of these elements are:</para> -<literallayout remap='.nf'> - send_interface="interface_name" - send_member="method_or_signal_name" - send_error="error_name" - send_destination="name" - send_type="method_call" | "method_return" | "signal" | "error" - send_path="/path/name" - - receive_interface="interface_name" - receive_member="method_or_signal_name" - receive_error="error_name" - receive_sender="name" - receive_type="method_call" | "method_return" | "signal" | "error" - receive_path="/path/name" - - send_requested_reply="true" | "false" - receive_requested_reply="true" | "false" - - eavesdrop="true" | "false" - - own="name" - own_prefix="name" - user="username" - group="groupname" -</literallayout> <!-- .fi --> - - -<para>Examples:</para> -<literallayout remap='.nf'> - <deny send_destination="org.freedesktop.Service" send_interface="org.freedesktop.System" send_member="Reboot"/> - <deny send_destination="org.freedesktop.System"/> - <deny receive_sender="org.freedesktop.System"/> - <deny user="john"/> - <deny group="enemies"/> -</literallayout> <!-- .fi --> - - -<para>The <deny> element's attributes determine whether the deny "matches" a -particular action. If it matches, the action is denied (unless later -rules in the config file allow it).</para> - -<para>send_destination and receive_sender rules mean that messages may not be -sent to or received from the *owner* of the given name, not that -they may not be sent *to that name*. That is, if a connection -owns services A, B, C, and sending to A is denied, sending to B or C -will not work either.</para> - -<para>The other send_* and receive_* attributes are purely textual/by-value -matches against the given field in the message header.</para> - -<para>"Eavesdropping" occurs when an application receives a message that -was explicitly addressed to a name the application does not own, or -is a reply to such a message. Eavesdropping thus only applies to -messages that are addressed to services and replies to such messages -(i.e. it does not apply to signals).</para> - -<para>For <allow>, eavesdrop="true" indicates that the rule matches even -when eavesdropping. eavesdrop="false" is the default and means that -the rule only allows messages to go to their specified recipient. -For <deny>, eavesdrop="true" indicates that the rule matches -only when eavesdropping. eavesdrop="false" is the default for <deny> -also, but here it means that the rule applies always, even when -not eavesdropping. The eavesdrop attribute can only be combined with -send and receive rules (with send_* and receive_* attributes).</para> - -<para>The [send|receive]_requested_reply attribute works similarly to the eavesdrop -attribute. It controls whether the <deny> or <allow> matches a reply -that is expected (corresponds to a previous method call message). -This attribute only makes sense for reply messages (errors and method -returns), and is ignored for other message types.</para> - - -<para>For <allow>, [send|receive]_requested_reply="true" is the default and indicates that -only requested replies are allowed by the -rule. [send|receive]_requested_reply="false" means that the rule allows any reply -even if unexpected.</para> - - -<para>For <deny>, [send|receive]_requested_reply="false" is the default but indicates that -the rule matches only when the reply was not -requested. [send|receive]_requested_reply="true" indicates that the rule applies -always, regardless of pending reply state.</para> - - -<para>user and group denials mean that the given user or group may -not connect to the message bus.</para> - - -<para>For "name", "username", "groupname", etc. -the character "*" can be substituted, meaning "any." Complex globs -like "foo.bar.*" aren't allowed for now because they'd be work to -implement and maybe encourage sloppy security anyway.</para> - - -<para><allow own_prefix="a.b"/> allows you to own the name "a.b" or any -name whose first dot-separated elements are "a.b": in particular, -you can own "a.b.c" or "a.b.c.d", but not "a.bc" or "a.c". -This is useful when services like Telepathy and ReserveDevice -define a meaning for subtrees of well-known names, such as -org.freedesktop.Telepathy.ConnectionManager.(anything) -and org.freedesktop.ReserveDevice1.(anything).</para> - - -<para>It does not make sense to deny a user or group inside a <policy> -for a user or group; user/group denials can only be inside -context="default" or context="mandatory" policies.</para> - - -<para>A single <deny> rule may specify combinations of attributes such as -send_destination and send_interface and send_type. In this case, the -denial applies only if both attributes match the message being denied. -e.g. <deny send_interface="foo.bar" send_destination="foo.blah"/> would -deny messages with the given interface AND the given bus name. -To get an OR effect you specify multiple <deny> rules.</para> - - -<para>You can't include both send_ and receive_ attributes on the same -rule, since "whether the message can be sent" and "whether it can be -received" are evaluated separately.</para> - - -<para>Be careful with send_interface/receive_interface, because the -interface field in messages is optional. In particular, do NOT -specify <deny send_interface="org.foo.Bar"/>! This will cause -no-interface messages to be blocked for all services, which is -almost certainly not what you intended. Always use rules of -the form: <deny send_interface="org.foo.Bar" send_destination="org.foo.Service"/></para> - -<itemizedlist remap='TP'> - - <listitem><para><emphasis remap='I'><selinux></emphasis></para></listitem> - - -</itemizedlist> - -<para>The <selinux> element contains settings related to Security Enhanced Linux. -More details below.</para> - -<itemizedlist remap='TP'> - - <listitem><para><emphasis remap='I'><associate></emphasis></para></listitem> - - -</itemizedlist> - -<para>An <associate> element appears below an <selinux> element and -creates a mapping. Right now only one kind of association is possible:</para> -<literallayout remap='.nf'> - <associate own="org.freedesktop.Foobar" context="foo_t"/> -</literallayout> <!-- .fi --> - - -<para>This means that if a connection asks to own the name -"org.freedesktop.Foobar" then the source context will be the context -of the connection and the target context will be "foo_t" - see the -short discussion of SELinux below.</para> - - -<para>Note, the context here is the target context when requesting a name, -NOT the context of the connection owning the name.</para> - - -<para>There's currently no way to set a default for owning any name, if -we add this syntax it will look like:</para> -<literallayout remap='.nf'> - <associate own="*" context="foo_t"/> -</literallayout> <!-- .fi --> -<para>If you find a reason this is useful, let the developers know. -Right now the default will be the security context of the bus itself.</para> - - -<para>If two <associate> elements specify the same name, the element -appearing later in the configuration file will be used.</para> - -</refsect1> - -<refsect1 id='selinux'><title>SELinux</title> -<para>See <ulink url='http://www.nsa.gov/selinux/'>http://www.nsa.gov/selinux/</ulink> for full details on SELinux. Some useful excerpts:</para> - - -<para>Every subject (process) and object (e.g. file, socket, IPC object, -etc) in the system is assigned a collection of security attributes, -known as a security context. A security context contains all of the -security attributes associated with a particular subject or object -that are relevant to the security policy.</para> - - -<para>In order to better encapsulate security contexts and to provide -greater efficiency, the policy enforcement code of SELinux typically -handles security identifiers (SIDs) rather than security contexts. A -SID is an integer that is mapped by the security server to a security -context at runtime.</para> - - -<para>When a security decision is required, the policy enforcement code -passes a pair of SIDs (typically the SID of a subject and the SID of -an object, but sometimes a pair of subject SIDs or a pair of object -SIDs), and an object security class to the security server. The object -security class indicates the kind of object, e.g. a process, a regular -file, a directory, a TCP socket, etc.</para> - - -<para>Access decisions specify whether or not a permission is granted for a -given pair of SIDs and class. Each object class has a set of -associated permissions defined to control operations on objects with -that class.</para> - - -<para>D-Bus performs SELinux security checks in two places.</para> - - -<para>First, any time a message is routed from one connection to another -connection, the bus daemon will check permissions with the security context of -the first connection as source, security context of the second connection -as target, object class "dbus" and requested permission "send_msg".</para> - - -<para>If a security context is not available for a connection -(impossible when using UNIX domain sockets), then the target -context used is the context of the bus daemon itself. -There is currently no way to change this default, because we're -assuming that only UNIX domain sockets will be used to -connect to the systemwide bus. If this changes, we'll -probably add a way to set the default connection context.</para> - - -<para>Second, any time a connection asks to own a name, -the bus daemon will check permissions with the security -context of the connection as source, the security context specified -for the name in the config file as target, object -class "dbus" and requested permission "acquire_svc".</para> - - -<para>The security context for a bus name is specified with the -<associate> element described earlier in this document. -If a name has no security context associated in the -configuration file, the security context of the bus daemon -itself will be used.</para> - -</refsect1> - -<refsect1 id='debugging'><title>DEBUGGING</title> -<para>If you're trying to figure out where your messages are going or why -you aren't getting messages, there are several things you can try.</para> - -<para>Remember that the system bus is heavily locked down and if you -haven't installed a security policy file to allow your message -through, it won't work. For the session bus, this is not a concern.</para> - -<para>The simplest way to figure out what's happening on the bus is to run -the <emphasis remap='I'>dbus-monitor</emphasis> program, which comes with the D-Bus -package. You can also send test messages with <emphasis remap='I'>dbus-send</emphasis>. These -programs have their own man pages.</para> - -<para>If you want to know what the daemon itself is doing, you might consider -running a separate copy of the daemon to test against. This will allow you -to put the daemon under a debugger, or run it with verbose output, without -messing up your real session and system daemons.</para> - -<para>To run a separate test copy of the daemon, for example you might open a terminal -and type:</para> -<literallayout remap='.nf'> - DBUS_VERBOSE=1 dbus-daemon --session --print-address -</literallayout> <!-- .fi --> - -<para>The test daemon address will be printed when the daemon starts. You will need -to copy-and-paste this address and use it as the value of the -DBUS_SESSION_BUS_ADDRESS environment variable when you launch the applications -you want to test. This will cause those applications to connect to your -test bus instead of the DBUS_SESSION_BUS_ADDRESS of your real session bus.</para> - -<para>DBUS_VERBOSE=1 will have NO EFFECT unless your copy of D-Bus -was compiled with verbose mode enabled. This is not recommended in -production builds due to performance impact. You may need to rebuild -D-Bus if your copy was not built with debugging in mind. (DBUS_VERBOSE -also affects the D-Bus library and thus applications using D-Bus; it may -be useful to see verbose output on both the client side and from the daemon.)</para> - -<para>If you want to get fancy, you can create a custom bus -configuration for your test bus (see the session.conf and system.conf -files that define the two default configurations for example). This -would allow you to specify a different directory for .service files, -for example.</para> - -</refsect1> - -<refsect1 id='author'><title>AUTHOR</title> -<para>See <ulink url='http://www.freedesktop.org/software/dbus/doc/AUTHORS'>http://www.freedesktop.org/software/dbus/doc/AUTHORS</ulink></para> - -</refsect1> - -<refsect1 id='bugs'><title>BUGS</title> -<para>Please send bug reports to the D-Bus mailing list or bug tracker, -see <ulink url='http://www.freedesktop.org/software/dbus/'>http://www.freedesktop.org/software/dbus/</ulink></para> -</refsect1> -</refentry> |