系统D-Bus不允许使用conf文件冲销所有权

Question

我正在尝试创建一个在系统总线上运行的守护程序服务,其中从此服务发送和接收的权限应该完全对任何人开放.(安全性不是此服务的关注点).当我尝试使用QtDbus(使用PyQt)注册服务时,我收到此错误:Connection ":1.0" is not allowed to own the service "org.dbus.arduino" due to security policies in the configuration file.这个其他堆栈溢出具有相同的错误,但由于某种原因在这种情况下根本没有帮助.dbus_bus_request_name ():不允许连接拥有该服务.

通常你应该保留system.conf文件,并在目录中添加你的权限"打出"配置文件system.d.我已经做到了这一点,但它似乎没有改变任何东西,无论我如何打开我的权限.事实上,我几乎是积极的,它没有改变任何东西!这是我的conf文件,因为它就在这一刻.

<!DOCTYPE busconfig PUBLIC
 "-//freedesktop//DTD D-BUS Bus Configuration 1.0//EN"
 "http://www.freedesktop.org/standards/dbus/1.0/busconfig.dtd">

<busconfig>
    <policy user="myUser">
        <allow own="*"/>
        <allow own="org.dbus.arduino"/>
        <allow send_type="method_call" log="true"/>
    </policy>                 
    <policy user="root">        
        <allow own="*"/>
        <allow own="org.dbus.arduino"/>
        <allow send_type="method_call" log="true"/>
    </policy>                         
    <policy context="default">            
    </policy>                                                     
</busconfig>                 

即使我这样做或类似的东西,它仍然不起作用.

<busconfig>               
    <policy context="default">     
        <allow own="*"/>
        <allow own="org.dbus.arduino"/>
        <allow send_type="method_call" log="true"/>       
    </policy>                                                     
</busconfig>  

我甚至把文件的名称以az开头,以便它可能是最后一个读入的文件.这是system.conf文件,注意我已经注释掉了"允许自己"部分.这是使其工作的唯一方法(以及最糟糕的"修复").

<!DOCTYPE busconfig PUBLIC "-//freedesktop//DTD D-Bus Bus Configuration 1.0//EN"
 "http://www.freedesktop.org/standards/dbus/1.0/busconfig.dtd">
<busconfig>

  <!-- Our well-known bus type, do not change this -->
  <type>system</type>

  <!-- Run as special user -->
  <user>messagebus</user>

  <!-- Fork into daemon mode -->
  <fork/>

  <!-- We use system service launching using a helper -->
  <standard_system_servicedirs/>

  <!-- This is a setuid helper that is used to launch system services -->
  <servicehelper>/lib/dbus-1/dbus-daemon-launch-helper</servicehelper>

  <!-- Write a pid file -->
  <pidfile>/var/run/dbus/pid</pidfile>

  <!-- Enable logging to syslog -->
  <syslog/>

  <!-- Only allow socket-credentials-based authentication -->
  <auth>EXTERNAL</auth>

  <!-- Only listen on a local socket. (abstract=/path/to/socket 
       means use abstract namespace, don't really create filesystem 
       file; only Linux supports this. Use path=/whatever on other 
       systems.) -->
  <listen>unix:path=/var/run/dbus/system_bus_socket</listen>

  <policy context="default">
    <!-- All users can connect to system bus -->
    <allow user="*"/>

    <!-- Holes must be punched in service configuration files for
         name ownership and sending method calls -->
    <deny own="*"/>
    <deny send_type="method_call" log="true"/>

    <!-- THIS IS THE ONLY WAY TO GET THIS TO WORK
    <allow own="*"/>
    <allow send_type="method_call" log="true"/>
    -->



    <!-- Signals and reply messages (method returns, errors) are allowed
         by default -->
    <allow send_type="signal"/>
    <allow send_requested_reply="true" send_type="method_return"/>
    <allow send_requested_reply="true" send_type="error"/>

    <!-- All messages may be received by default -->
    <allow receive_type="method_call"/>
    <allow receive_type="method_return"/>
    <allow receive_type="error"/>
    <allow receive_type="signal"/>

    <!-- Allow anyone to talk to the message bus -->
    <allow send_destination="org.freedesktop.DBus"/>
    <!-- But disallow some specific bus services -->
    <deny send_destination="org.freedesktop.DBus"
          send_interface="org.freedesktop.DBus"
          send_member="UpdateActivationEnvironment"/>

  </policy>

  <!-- Config files are placed here that among other things, punch 
       holes in the above policy for specific services. -->
  <includedir>system.d</includedir>

  <!-- This is included last so local configuration can override what's 
       in this standard file -->
  <include ignore_missing="yes">system-local.conf</include>

  <include if_selinux_enabled="yes" selinux_root_relative="yes">contexts/dbus_contexts</include>

</busconfig>

我绝对必须使用系统总线,因为我将它部署在没有GUI的Raspberry Pi上(没有x11,没有会话总线).我只能通过完全允许系统总线上的所有内容来获得Raspberry Pi的工作(安全性并不是这个设备上的大部分交易).显然,我不允许在我的开发机器上发生这种情况.作为背景我使用的是Opensuse 12.2,Raspberry Pi是Debian Squeeze.我无法使用我的用户帐户或root用户拥有该服务,除非我完全打开权限,在这种情况下它可以正常工作.我还要注意,当我完全打开系统总线时,我仍然必须使用root来向守护进程发送消息(终止命令).我希望解决方案能够通过具有访问权限的root的特定用户运行.我也很满意解决方案只允许同一个用户和root用户向它发送消息.

感谢您的帮助,我相信这是一个小问题!

Answer 1

我终于找到了这个问题.当Dbus查找配置文件以查找权限(如所有权)时,该文件不仅必须在system.d /中,而且还必须以.conf结尾.

我的配置文件"org.dbus.arduino"应该是"org.dbus.arduino.conf".我从system.conf中删除了代码.确认我不再拥有权限,在"system.d/org.dbus.arduino.conf"创建配置文件,我被授予权限.然后我尝试将文件重命名为"org.dbus.arduino"并确认权限被拒绝.