Can't start Tor Control panel in sys-whonix Qubes 4.1

[tzwcfq]

I’ve installed Qubes 4.1 with latest current-testing updates and I can’t start Tor Control panel in sys-whonix but Anon Connection Wizard works fine and tor works fine as well.
When I try to start Tor Control panel from terminal then I’m getting this error:

user@host:~$ sudo --set-home tor-control-panel 
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
QLayout: Attempting to add QLayout "" to QFrame "", which already has a layout
Traceback (most recent call last):
  File "/usr/bin/tor-control-panel", line 8, in <module>
    tor_control_panel.main()
  File "/usr/lib/python3/dist-packages/tor_control_panel/tor_control_panel.py", line 760, in main
    tor_controller.refresh(True)
  File "/usr/lib/python3/dist-packages/tor_control_panel/tor_control_panel.py", line 716, in refresh
    self.refresh_user_configuration()
  File "/usr/lib/python3/dist-packages/tor_control_panel/tor_control_panel.py", line 664, in refresh_user_configuration
    args = torrc_gen.parse_torrc()
  File "/usr/lib/python3/dist-packages/tor_control_panel/torrc_gen.py", line 128, in parse_torrc
    bridge_type = bridges_display[bridges_type.index(bridge_type)]
IndexError: list index out of range
QThread: Destroyed while thread is still running
Aborted

UPD:
It seems that the problem is that I’ve added bridges with pluggable transport ‘none’. When I add bridges with pluggable transport ‘obfs4’ then I can open Tor Control panel again.

[tzwcfq]

This is Tor Control panel bug and is unrelated to Qubes. I’ve tested it with Whonix on KVM and it fails in the same way.
I’ve found a workaround:
If you add at least one obfs4 bridge in you config in Anon Connection Wizard and add your other bridges with transport ‘none’ then the Tor Control panel can be started and used again.

UPD:
It seems that it’s enough to just add ClientTransportPlugin in torrc config and it works even without adding obfs4 bridge:

sudo sh -c 'echo "ClientTransportPlugin obfs4 exec /usr/bin/obfs4proxy" >> /usr/local/etc/torrc.d/40_tor_control_panel.conf'

Also it doesn’t work if I add ClientTransportPlugin /usr/local/etc/torrc.d/50_user.conf.

[Patrick]

A bug that should be fixed one day. Help welcome.

Meanwhile:

• Don’t use bridges of type none. Nowadays obfs4 is available so why downgrade.
• Try Anon Connection Wizard - Whonix.
• File /usr/local/etc/torrc.d/40_tor_control_panel.conf can be deleted

  • sudo rm /usr/local/etc/torrc.d/40_tor_control_panel.conf

  • and then re-created using
    • Tor Control Panel or
    • Anon Connection Wizard - Whonix
    • Manual Bridge Configuration

What to expect from Tor Control Panel / Anon Connection Wizard and what not, see:
Unsuitable Connectivity Troubleshooting Tools

[tzwcfq]

@Patrick

Don’t use bridges of type none. Nowadays obfs4 is available so why downgrade.

The obfs4 bridges that I’m getting from bridges-torproject-org are mostly don’t work for me (I guess my ISP is actively banning tor bridges) or are stopping to work after some time. But bridges with type none are working fine I guess my ISP is not banning them so actively.

@Patrick

Try [Anon Connection Wizard - Whonix]

Anon Connection Wizard works fine as I’ve stated above. Tor Control panel was just more convenient as I could just see the Tor connection status and easily restart tor with the button.