Cannot change qubes-gui-daemon settings using qvm-features

arraybolt3 · October 4, 2024, 1:26am

I’m hacking on the qubes-gui-daemon code, and have successfully implemented a new feature into it. (Add X event buffering for cloaking user input patterns by ArrayBolt3 · Pull Request #149 · QubesOS/qubes-gui-daemon · GitHub for those who are interested) This feature needs to have a configurable setting, so I tried to implement a new configuration option for it. Supposedly qubes-gui-deamon settings can be set using the qvm-features tool. However, I’m having trouble doing this, and can reproduce the issue I had using a previously existing feature that my new feature should not affect.

Looking at /etc/qubes/guid.conf, there’s a setting called windows_count_limit that allows you to specify how many windows a Qube can have open at any one time. This looked like a pretty easy setting to verify if it worked or not, and so I tried setting the maximum number of allowed windows to 2. Following the instructions from the qvm-features manpage, I ran:

qvm-features work gui-windows-count-limit 2

(work being the name of a Fedora 40 Qube on my system.) This command seemed to work, if I run qvm-features work I can see the gui-windows-count-limit setting has been set to 2. To make sure the settings were being applied, I shut down the work Qube entirely, then started it back up. Once it was booted, I launched three XFCE Terminal windows in it, and all three of them appeared on my desktop, which seems wrong since I specifically requested a maximum of two windows to be allowed.

Naturally this isn’t the only configuration option that isn’t working - the configuration option for my new feature similarly is silently ignored. Just in case, I also tried setting configuration options directly in /etc/qubes/guid.conf despite the fact that it says it isn’t read, and that similarly failed. (I only tried this with my custom configuration option, and it was silently ignored.)

Am I using qvm-features wrong? Or is this config file telling me to try to set settings in the wrong spot perhaps? What should I do in order to configure qubes-gui-daemon?

apparatus · October 4, 2024, 6:06am

The gui-windows-count-limit support was removed:

qubes-gui-daemon (4.1.20-1) unstable; urgency=medium

  [ Demi Marie Obenour ]
  * Remove windows_count from Ghandles

You can try this

qvm-features work gui-allow-utf8-titles 1

This works for me.

Check the ./gui-daemon/xside.c and ./gui-daemon/xside.h files in qubes-gui-daemon.

apparatus · October 4, 2024, 6:42am

I guess you need to add your GUI daemon option here as well:

github.com

QubesOS/qubes-core-admin-client/blob/30d75476b9ee181be04c8143a32b6416f6dc432f/qubesadmin/tools/qvm_start_daemon.py#L50


      
          from qubesadmin.tools import xcffibhelpers
          
          GUI_DAEMON_PATH = '/usr/bin/qubes-guid'
          PACAT_DAEMON_PATH = '/usr/bin/pacat-simple-vchan'
          QUBES_ICON_DIR = '/usr/share/icons/hicolor/128x128/devices'
          
          GUI_DAEMON_OPTIONS = [
              ('allow_fullscreen', 'bool'),
              ('override_redirect_protection', 'bool'),
              ('override_redirect', 'str'),
              ('allow_utf8_titles', 'bool'),
              ('secure_copy_sequence', 'str'),
              ('secure_paste_sequence', 'str'),
              ('windows_count_limit', 'int'),
              ('trayicon_mode', 'str'),
              ('window_background_color', 'str'),
              ('startup_timeout', 'int'),
          ]
          
          formatter = logging.Formatter(
              '%(asctime)s - %(name)s - %(levelname)s - %(message)s')

arraybolt3 · October 4, 2024, 7:25am

oh so that’s what I was missing. Thanks for the pointer, I would have never caught that, or at least it would have taken me a while.

w.r.t. the option for window count being removed, perhaps it should be removed from the config file if it’s no longer a thing.

apparatus · October 4, 2024, 7:28am

The config file should be just removed:

github.com/QubesOS/qubes-issues

Update documentation that refers to vestigial /etc/qubes/guid.conf, and eventually remove it

opened 05:09PM - 17 Jun 24 UTC

Euwiiwueir

T: bug C: doc P: default diagnosed

[How to file a helpful issue](https://www.qubes-os.org/doc/issue-tracking/) #…## Qubes OS release 4.1+ ### Brief summary Global and per-VM `qubes-guid` configuration used to be done by way of the file `/etc/qubes/guid.conf`. Since release 4.1 configuration of `qubes-guid` transitioned to `qvm-features`, with this updated note in the manpage: ``` gui-*, gui-default-* GUI daemon configuration. See /etc/qubes/guid.conf for a list of sup‐ ported options. To change a given GUI option for a specific qube, set the gui-{option} feature (with underscores replaced with dashes). For example, to enable allow_utf8_titles for a qube, set gui-allow-utf8-titles to True. To change a given GUI option globally, set the gui-default-{option} feature on the GuiVM for that qube. ``` And in `/etc/qubes/guid.conf`: ``` # Default configuration file for Qubes GUI daemon # (For syntax go http://www.hyperrealm.com/libconfig/libconfig_manual.html) # EDITING THIS FILE WILL NOT HAVE ANY EFFECT! It is not read by the GUI daemon # anymore, and is left here for reference only. To configure the GUI daemon, # use qvm-features (see 'man qvm-features' for details). ... ``` However, other documentation refers to this file as still being effective: https://www.qubes-os.org/doc/config-files/#gui-and-audio-configuration-in-dom0 https://github.com/QubesOS/qubes-doc/blob/03ebdad8f96e0f21f65a5e1f1f9ade5af9b254c9/user/advanced-topics/config-files.md https://www.qubes-os.org/doc/how-to-enter-fullscreen-mode/#enabling-fullscreen-mode-for-select-vms https://github.com/QubesOS/qubes-doc/blob/03ebdad8f96e0f21f65a5e1f1f9ade5af9b254c9/user/how-to-guides/how-to-enter-fullscreen-mode.md **To fix:** - Move the useful documentation remaining in `/etc/qubes/guid.conf` directly into the `qvm-features` manpage (https://github.com/QubesOS/qubes-core-admin-client/blob/main/doc/manpages/qvm-features.rst) - Update https://github.com/QubesOS/qubes-doc/blob/main/user/how-to-guides/how-to-enter-fullscreen-mode.md - Update https://github.com/QubesOS/qubes-doc/blob/main/user/advanced-topics/config-files.md - Update [xside.c](https://github.com/QubesOS/qubes-gui-daemon/blob/main/gui-daemon/xside.c), [xside.h](https://github.com/QubesOS/qubes-gui-daemon/blob/main/gui-daemon/xside.h) to remove references to `/etc/qubes/guid.conf` - Eventually: remove [`/etc/qubes/guid.conf`](https://github.com/QubesOS/qubes-gui-daemon/blob/main/gui-daemon/guid.conf) and connected build/installation infrastructure ### Steps to reproduce Click documentation links above ### Expected behavior Documentation refers to `qvm-features` rather than `/etc/qubes/guid.conf` ### Actual behavior Documentation is misleading

But the windows_count_limit should be removed from qvm_start_daemon.py.