Bug 492265

Summary:	KRDC receives Authentication Failed from KRFB
Product:	[Applications] krdc	Reporter:	Freek de Kruijf <freekdekruijf>
Component:	VNC	Assignee:	Urs Wolfer <uwolfer>
Status:	RESOLVED WORKSFORME
Severity:	normal	CC:	ctrlaltca
Priority:	NOR
Version First Reported In:	24.05.2
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Freek de Kruijf 2024-08-27 12:24:14 UTC

I have KRFB started on a Raspberry Pi 4B in a XFCE session on Leap 15.6. I see KRFB is listening on port 5900. I start KRDC on a Tumbleweed x86_64 system in the same LAN and start a VNC session to the RPi4 using the IP address of that system. Using lsof on the RPi4, I see there is an established session between KRFB and KRDC. I enabled unguarded access in KRFB, so no prompt for allowing access appears.

Entering the password shown in the KRFB in the KRDC window gives the error: Authentication failed.

In .xsession-errors on the RPi4 I see:

libEGL warning: DRI2: failed to authenticate
libEGL warning: MESA-LOADER: failed to open zink: /usr/lib64/dri/zink_dri.so: cannot open shared object file: No such file or directory (search paths /usr/lib64/dri, suffix _dri)

SUMMARY
KRDC receives Authentication Failed from KRFB

STEPS TO REPRODUCE
1. Start KRFB on remote system on LAN and note password
2. Start KRDC on local system on LAN
3. Start connection to KRFB system and fill in the password

OBSERVED RESULT
Authentication failed

EXPECTED RESULT
Authentication succeeded.

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
(available in the Info Center app, or by running `kinfo` in a terminal window)
Linux/KDE Plasma: 6.10.5
KDE Plasma Version: 6.1.4
KDE Frameworks Version: 5.116.0
Qt Version: 6.7.2

ADDITIONAL INFORMATION

Comment 1 Fabio 2025-08-27 12:41:38 UTC

In local tests I've not been able to reproduce this problem on recent krfb/krdc versions.
It would have been nice to:
 * see if another vnc client is able to connect to the krfb server
 * run krdc from the commandline to get its logs 
 * get the krfb server logs

Are you still able to reproduce this problem now?

Comment 2 Bug Janitor Service 2025-09-11 03:49:01 UTC

🐛🧹 ⚠️ This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information, then set the bug status to REPORTED. If there is no change for at least 30 days, it will be automatically closed as RESOLVED WORKSFORME.

For more information about our bug triaging procedures, please read https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging.

Thank you for helping us make KDE software even better for everyone!

Comment 3 Bug Janitor Service 2025-09-26 03:47:31 UTC

🐛🧹 This bug has been in NEEDSINFO status with no change for at least 30 days. Closing as RESOLVED WORKSFORME.