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BUG: SC using ZRLE encoding even though not told to

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jollyjinx
Posts: 2
Joined: 2008-01-25 12:44
Location: Germany
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BUG: SC using ZRLE encoding even though not told to

Post by jollyjinx »

Dear developers,

I'm the developer of JollysFastVNC and it seems that your VNC SC server is not correctly speaking the VNC protocol.

It uses the ZRLE protocol even though my client never told it that it supports ZRLE. My client supports Tight and zlib encoding and it seems as soon as my client says it supports zlib encoding UVNC SC will then choose zrle.

Furthermore UVNC beginns the reverse connection by saying it speaks 003.016 vnc protocol. The standard then would suggest as the minor protocol is > 7 we should speak 003.008 protocol. UVNC SC does then not correctly respond to the security features. It will only respond correctly during the initiation when the protocol by the client requested is 003.003.


Regards Patrick Stein
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I'm not reading your list so ask questions by mail.
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author of ScreenRecycler, JollysFastVNC
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Rudi De Vos
Admin & Developer
Admin & Developer
Posts: 6863
Joined: 2004-04-23 10:21
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Re: BUG: SC using ZRLE encoding even though not told to

Post by Rudi De Vos »

SC is a cut down version, minimal size.
Tight is not supported and default to zrle

SC use a lot of options that are Ultravnc only , extra rfb was needed
( encryption plugins, repeater etc...)
to tell it to the viewer.

I don't think 3.0.8 already existed when we made SC, at that time
the rfb protocol above 3.0.5 was not set.
jollyjinx
Posts: 2
Joined: 2008-01-25 12:44
Location: Germany
Contact:

Re: BUG: SC using ZRLE encoding even though not told to

Post by jollyjinx »

Uih, quick reply.

If it defaults to ZRLE than that's definitely an error, as the VNC protocol says to read the encodings the viewer supports and then choose accordingly from top to bottom.
Choosing an encoding the viewer does not support is wrong.

It does not use ZRLE if my viewer says that it does not support Zlib. So the mechnism should be to only choose ZRLE when the viewer says so.

Right now users have to disable all encodings in the viewer to get it working with UVNC SC at all.

Regards - Patrick
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author of ScreenRecycler, JollysFastVNC
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