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Abnormality of NO AUTHENTICATION Server

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YY
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Joined: 2006-11-13 15:11

Abnormality of NO AUTHENTICATION Server

Post by YY »

I found a problem when UVNC server is configured to NO AUTHENTICATION, i.e.

AuthRequired=0 (inside Ultravnc.ini), and
VNC Password & View Only Password both are nul/blank


My tests are done on WinXP Prof, with UVNC started as service. Here are what I found:

1. When the system is boot, the following error message popup: Image
This is normal, but not completely accurate.
"To prevent user from enabling authentication" ..... No, "AuthRequired=0" doesn't mean it or imply this.

 When I logon into my admin a/c, here are what I found:
 - sometimes (not always) the EYE icon not showing on the Sys-tray.
 - the "-autoreconnt ....." inside "service_commandline=" not working.
  In fact, it worked once, and then never tried to reconnect.
 - When I tried to stop the uvnc_service, it was not shutdown properly,
  There was one winvnc.exe keep on running, exactly as the case of the bug of 1.0.9.5 with AllowShutdown=0



2. When the system has been bootup, and I start uvnc_service manually.

 Following the about test, I stopped the uvnc_service, and killed the remained winvnc.exe session, and then start it again
 - the about VNC Error window was not show in this situation.
 - the "service_commandline=-autoreconnet ...... " working properly
 - the uvnc_service can be stopped prolerly


Base on my observation:
- The code excuted at bootup has a bug, that affect the proper initiation of UVNC
- In the condition of AuthRequired=0 & NUL password, the code (during bootup) incorrectly implied the setting "AllowShutdown=0" as well, thus trigger the shutdown problem of "1.0.9.5 with AllowShutdown=0". This is considered have been fixed on 1.0.9.6, but may be not.
Last edited by YY on 2011-05-07 03:56, edited 2 times in total.
YY
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Posts: 996
Joined: 2006-11-13 15:11

Re: Abnormality of NO AUTHENTICATION Server

Post by YY »

I found more characteristic of this issue .....

YY wrote:1. When the system is boot, the following error message popup: Image
Condition A
during the VNC Error window popup at bootup, if I click "OK" or close it, and then logon. I found that:
- Most likely the EYE icon will appear on the Sys-tray properly (I just try about 5-10 times, this need booting the pc)
- the "-autoreconnt ....." inside "service_commandline=" will work once. If not got connect it will NOT reconnect (as what I reported on my 1st post).
- The uvnc_service can be shutdown properly. ie. both winvnc.exe sessions can be terminated.


Condition B
OR, when this error message popup, if the mouse pointer click on other part of the desktop, this popup will be vanished .... (IN FACT IT STILL EXIT, it is just hided/covered by the Win Logon screen), you just see the Win Logon screen.

If I logon with this condition, the problems I reported appear ...
- sometimes (not always) the EYE icon not showing on the Sys-tray.
- the "-autoreconnt ....." inside "service_commandline=" not working. (completely no connection, not even once.)
- When I tried to stop the uvnc_service, it was not shutdown properly (one winvnc.exe keep on running)



Condition C
OK in the situation of Condition B, i.e. I ignor the VNC Error window and logon-ed, I still have a chance to rectify:
- Just logout, and Windows will return to the Win Logon Screen
- at a short moment (about 5 seconds), the VNC Error window will appear, at this moment click "OK" or close it.
- if you miss this chance, of couse you do it again by log on and then log out again.
- When this Error window is proplerly closed, the UVNC looks like working more normally


My comment:
- If this VNC Error window not closed, the UVNC not working properly
- Even the VNC Error window is closed, the "service_commandline=-autoreconnect ...." still not working. Or the problem is: AllowShutdown=0, the "service_commandline=-autoreconnect ...." not working.
Last edited by YY on 2011-05-07 03:57, edited 2 times in total.
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Rudi De Vos
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Re: Abnormality of NO AUTHENTICATION Server

Post by Rudi De Vos »

The problem seems to be that the warning message should never
be displayed running as service.
Now it display it when running as non admin, but running as service with no logon -> no user -> no admin -> Messagebox...

winvnc startup lock at init properties until you press OK.
Without the press OK, this thread is loked.

1) this lock prevent shutdown, no more session switches possible.
2) partial init is done, a lot of stuff can happen..

Added extra check to disable warning when running as service.

[post=85761][/post]

You reported some -autoreconnect issue's... are this related to this one
or still exist after this change?
Last edited by Rudi De Vos on 2011-04-16 18:25, edited 2 times in total.
YY
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Posts: 996
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Re: Abnormality of NO AUTHENTICATION Server

Post by YY »

Rudi De Vos wrote:Added extra check to disable warning when running as service.
Thanks for you rapid response. :P :P

Rudi De Vos wrote:[post=85761][/post]

You reported some -autoreconnect issue's... are this related to this one
or still exist after this change?
Just download this beta version.

But before I verify if this fixed those old problem I reported, I found another serious one, which I think should be fixed first.

Please see [topic=27955]BUG: Old Version Viewer will crash Server 1.0.9.6[/topic]
Last edited by YY on 2011-04-17 09:52, edited 1 time in total.
YY
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Joined: 2006-11-13 15:11

Re: Abnormality of NO AUTHENTICATION Server

Post by YY »

Rudi De Vos wrote:Added extra check to disable warning when running as service.
Have tested the 10961 Dated 18-Apr-2011. The reported problem is eliminated. :)

Just a question, I cannot locate this VNC Error popup, even I start the winvnc.exe in application mode. Is this message removed completely ?


Rudi De Vos wrote:You reported some -autoreconnect issue's... are this related to this one or still exist after this change?
Still exist.
Please see [topic=27927]Bug: Autoreconnect function broken on 1.0.9.6[/topic]
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Rudi De Vos
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Re: Abnormality of NO AUTHENTICATION Server

Post by Rudi De Vos »

authrequired=0 the admin allowed non passwd access.

Only if winvnc is started as non admin user, you get the warning, the admin need to know what he does.
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