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X11vnc server stores the passwords nearly in plaintext (there is an option to get the password back from the password file). Therefore i want to implement a password check using sha256 or another hashfunction, which is harder to reverse. In the man page are some hints, how to implement an own password checker. It is written that -unixpw_cmd should be the way to go, but unfortunatly I only get this error message when trying to log in:

$ vncviewer localhost
Connected to RFB server, using protocol version 3.8
Server did not offer supported security type

I use this server commandline:

x11vnc -ssl -forever -shared -unixpw -unixpw_cmd ./vncpwcheck

And this script:

#!/bin/bash
read user
read pass
echo -n $pass | sha256sum --status -c passwdfile

The passwdfile looks like this:

2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae  -

What do I forget? The man page says everthing how to use the single options but nothing which other options are needed that it works?

Alex Stragies
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reox
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