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Encryption plugin help

Post Reply
cultclassic
Posts: 1
Joined: 2018-03-23 23:14

Encryption plugin help

Post by cultclassic »

Hi

I have ultravnc server on a Win 7 machine. I also
installed and configured the encryption plugin,
and generated the public and private keys.
Are there any more steps to get encryption to
work? Because when I try to connect from another
windows or linux mint machines, I get the warning the
that the connection is not secure.
A client on ubuntu gave me this error:
"unknown authentication scheme from vnc server 17 151 153"
Am I missing some steps?

Thanks
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Rudi De Vos
Admin & Developer
Admin & Developer
Posts: 6867
Joined: 2004-04-23 10:21
Contact:

Re: Encryption plugin help

Post by Rudi De Vos »

encryption plugin
**you need a server and viewer that support the plugins

**Simple mode,
Nothing to confgure, just select use [v]

Image

If you configure the plugin
1) You can set a longer password ( Passphrase)
This way, the encryption plugin encrypt the data and authenticate with a stronger key

2) You can generate a server and viewer key
*server key stay on the server in the same folder as the plugin and winvnc
*viewer key is copied to the same folder as the viewer and plugin
This way, the key act as authentication and encryption. Only the viewer with the key can connect.

I don't know if someone has implemented the plugins for unix else you are restricted to the version that support it
mhertz
20
20
Posts: 39
Joined: 2018-02-27 20:19

Re: Encryption plugin help

Post by mhertz »

For linux, the only viewer i'm aware of supporting ultravnc encryption(+ ultravnc chat, file-transfer, repeater and mslogon) is ssvncviewer, an enhanced and patched tightvnc v1.3.9 viewer, provided in the ssvnc package from Karl Runge. I'm not fully sure if it supports also the securevncplugin.dsm, or only the older msrc4plugin.dsm. It's rather old though, not updated since 2011, but works fine. Additionally, it's the only linux vncviewer I could get to connect to an ultravnc SC server, as ultravnc SC reports supporting RFB3.16, and all the viewers don't get that and uses 3.8 which isn't compatible. It works in RFB3.3 mode, which ssvncviewer uses automatically when connecting to ultravnc SC servers. Btw, you can also install cygwin/openssh(or on win10 possibly opt for the native openssh-beta, or the linux-subsystem/openssh) and simply encrypt using ssh-tunnel with any vncviewer, which is what I do currently(I use the vncviewer from tigervnc which is currently updated and slightly faster).

Ohh, I forgot, in the ssvnc package, there's also a standalone command-line tool ultravnc_dsm_plugin, which you can use with any vncviewer. Too bad development has ceased with these great tools, though atleast we still have them available and many things(all?) works as promised - Karl Runge rocks! He's also the one behind the nice x11vnc which adds winvnc functionality to *nix i.e. connect to real X display instead of dynamic one.

http://www.karlrunge.com/x11vnc/ssvnc.html
simonleung2020
Posts: 1
Joined: 2020-01-31 10:08

Re: Encryption plugin help

Post by simonleung2020 »

Rudi De Vos wrote:encryption plugin
**you need a server and viewer that support the plugins

**Simple mode,
Nothing to confgure, just select use [v]

Image

If you configure the plugin
1) You can set a longer password ( Passphrase)
This way, the encryption plugin encrypt the data and authenticate with a stronger key

2) You can generate a server and viewer key
*server key stay on the server in the same folder as the plugin and winvnc
*viewer key is copied to the same folder as the viewer and plugin
This way, the key act as authentication and encryption. Only the viewer with the key can connect.

I don't know if someone has implemented the plugins for unix else you are restricted to the version that support it

To enable encryption, do I just need to use plugin and create password? Do I have to generate server and viewer key?
User avatar
Rudi De Vos
Admin & Developer
Admin & Developer
Posts: 6867
Joined: 2004-04-23 10:21
Contact:

Re: Encryption plugin help

Post by Rudi De Vos »

To enable
A) enable the plugin
data is encrypted and the standard vnc password is used
B) enable the plugin + set passphrase
data is encrypted and the passphrase is used
C) create keys
data is encrypted and keys are used for encryption and authentication

You can use A,B or C
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