Ubuntu Manpage: vnc.conf - configuration file for Virtual Network Computing

Provided by: tigervnc-standalone-server_1.7.0+dfsg-8ubuntu2_amd64

NAME

       vnc.conf - configuration file for Virtual Network Computing

SYNOPSIS

       $variable = "someValue";

       $variable = "someValue";

       $variable .= "someValue";

       $variable = $var1 . $var2;

DESCRIPTION

       /etc/vnc.conf  is  the  site wide configuration file for tigervncserver(1), the free X server for Virtual
       Network Computing (VNC). It can be used to change the behavior of the server at  startup  time,  although
       for all values suitable defaults are preset.

       vnc.conf will be parsed by tigervncserver. Then tigervncserver will proceed and read $HOME/.vnc/vnc.conf,
       a  file  that can be changed on a per-user base. It has the some syntax and options as the file described
       in this document.

EXAMPLES

       The site wide configuration file /etc/vnc.conf should come with the Debian  package  tigervnc-standalone-
       server.   This  file  serves  as  an  example  for  the  user  file  $HOME/.vnc/vnc.conf.   The site wide
       configuration file is pretty self-descriptive, and this document will mainly repeat the information  that
       already can be found there.

OVERVIEW

       The  file  is  in  perl(1)  syntax,  although  only  variable  assignment  is allowed for your safety and
       convenience. But there still a variety of possibilities to set the string variables.

       All variable names are prefixed by `$'. You can assign a string to a variable using the `=' operator, and
       you can append a string to a variable using the `.=' operator. You can concatenate two strings using  the
       `.'   operator. You can substitute variables even inside quotes. You can access the environment variables
       using the notation $ENV{VARIABLE}.

       You can unset a variable by assigning undef to it. Use this to return the  state  of  the  variable  from
       `set' to `use default'.

       You must end a line with a semicolon.

OPTIONS

The options are given with their default value if this is known.

$vncClasses = "/var/www/vnc";
Should be the path to the java classes of the server.

$baseHttpPort = undef;
This is the port base for the mini-HTTP server that is built-in to Xtigervnc(1). The real http
port will be derived from this base plus the display number.

$XFConfigPath = "/etc/X11/xorg.conf";
Can be set to the global xorg.conf file. This will be parsed to gain default values for $fontPath.
If you want to disable this feature, point it to an invalid file, /invalid for example.

$fontPath
Should be a comma separated list of fonts to be added to the font path. If not specified, and
$XFConfigPath is valid, tigervncserver will read the $fontPath from there. If both are not set,
the default will apply.

$PAMService = "tigervnc";
This parameter specifies the PAM service used for plain password authentication if one of the
security types Plain, TLSPlain, or X509Plain is used. If /etc/pam.d/vnc is not present, then
tigervncserver(1) expects to use the tigervnc PAM service to authenticate the passwords of users
when any of the *Plain security types are used. Note that the tigervnc-common package provides
the PAM service configuration file /etc/pam.d/tigervnc. Otherwise, if /etc/pam.d/vnc is present,
then the vnc PAM service will be used.

$sslAutoGenCertCommand = "openssl req
-newkey ec:/etc/tigervnc/ecparams.pem
-x509 -days 2190 -nodes";
The command specified by the $sslAutoGenCertCommand parameter is used to auto generate the
certificate for the -X509Cert and -X509Key options of Xtigervnc(1). The configuration for
openssl(1SSL) is taken from /etc/tigervnc/ssleay.cnf where we substitute @HostName@ by the fully
qualified domain name of the host.

$vncUserDir = "$ENV{HOME}/.vnc";
Contains the filename for the log files directory of Xtigervnc (the server) and the viewers that
are connected to it.

$vncPasswdFile = $vncUserDir . "/passwd";
Contains the filename of the password file for Xtigervnc. This file is only used for the security
types VncAuth, TLSVnc, and X509Vnc.

$vncStartup = "/etc/X11/XSession";
Points to a script that will be started at the very beginning of the Xtigervnc session.

$xauthorityFile = "$ENV{HOME}/.Xauthority";
Specifies the path to the X authority file that should be used by your Xtigervnc server.

$desktopName = "${HOSTFQDN}:nn ($ENV{LOGNAME})";
Should be set to the default name of the desktop. This can be changed at the command line with
-name.

$wmDecoration = "8x64";
Sets the adjustment of $geometry to accommodate the window decoration used by the X11 window
manager. This is used to fully display the VNC desktop even if the VNC viewer is not in full
screen mode.

$geometry = "1900x1200";
This sets the framebuffer width & height. A default for this option as well as the $depth and
$pixelformat options can be derived if the tigervncserver(1) is run in a X session – either
$ENV{DISPLAY} or the session given by $getDefaultFrom – with the -xdisplaydefaults option. The
geometry can also be changed at the commandline with the -geometry option. Otherwise, the fixed
defaults given here as well as in the following two configuration parameter documentations will be
used.

$depth = "32";
This sets the framebuffer color depth, i.e., the number of bits per pixel to use. It must be
either 32, 24, 16, or 8.

$pixelformat = "rgb888";
Specifies the pixel format for the Xtigervnc(1) server to use (BGRnnn or RGBnnn). The default for
depth 8 is BGR233 (meaning the most significant two bits represent blue, the next three green, and
the least significant three represent red), the default for depth 16 is RGB565 and for depth 24
and 32 is RGB888.

$getDefaultFrom
This option lets you set the display from which you can query the default of the above three
options, if you don't want to start tigervncserver from within a running X server. It will be
added to the call of xdpyinfo. It is useful to get the default from the X server you will run
xvncviewer in, because the data has not to be recalculated then.

$getDefaultFrom = "-display localhost:0"; is an example how to do this.

$rfbwait = "30000";
Sets the maximum time in msec to wait for the VNC client viewer.

$localhost = "yes";
Should the TigerVNC server only listen on localhost for incoming TigerVNC connections. This is
useful if you use SSH and want to stop non-SSH connections from any other hosts. Hence,
$localhost = "yes" is the default if security types are not specified. In this case, only the
security type VncAuth will be offered. If the security types are specified, either via the option
-SecurityTypes given to tigervncserver(1) or via the $SecurityTypes configuration parameter in
/etc/vnc.conf or in $HOME/.vnc/vnc.conf, then the default depends on the specified security types.
The default will be $localhost = "no" if the specified security types contain at least one of the
TLS* or X509* secutity types and also contain none of the *None security types. As always, the
defaults can be overwritten on the commandline via the -localhost option or via the $localhost
configuration parameter in /etc/vnc.conf or in $HOME/.vnc/vnc.conf.

$SecurityTypes = "VncAuth"
The $SecurityTypes parameter contains a comma separated list of the default security types the
Xtigervnc server will offer. Available security types are None, VncAuth, Plain, TLSNone, TLSVnc,
TLSPlain, X509None, X509Vnc and X509Plain. The *None security types do not offer any kind of
user authentication for connecting VNC sessions. Hence, combining a *None security type and
$localhost = "no" is a very bad idea. The TLS* and X509* security types do enforce SSL
encryption for data transmission. Hence, combining a TLS* or X509* security type and
$localhost = "yes" is a senseless idea. Thus, in the case of $localhost = "no", the default for
$SecurityTypes will be extended from VncAuth to VncAuth,TLSVnc.

$PlainUsers = "$ENV{LOGNAME}"
The $PlainUsers configuration parameter contains a comma separated list of users that are
authorized to access the VNC server if the security types Plain, TLSPlain, or X509Plain are used
to establish the connection. The password for these users are check by the system via the PAM
service specified via $PAMService option. On default, only the user starting the tigervncserver is
contained in the list. By specifying *, any user can authenticate using this security type.

$X509Cert and $X509Key
These two options contain the filenames for a certificate and its key that is used for the
security types X509None, X509Vnc, and X509Plain. If nothing is specified – the default case –
then a self-signed certificate is auto-generated by tigervncserver(1) and stored in
$HOME/.vnc/${HOSTFQDN}-SrvCert.pem and $HOME/.vnc/${HOSTFQDN}-SrvKey.pem, respectively. If
filenames are given for $X509Cert and $X509Key either here or on the commandline via -X509Cert and
-X509Key options, then the auto generation is disabled and the user has to take care that usable
certificates are present.

FILES

       /usr/bin/tigervncserver
              A wrapper script around Xtigervnc to start the server with appropriate defaults.

       /usr/bin/tigervncpasswd
              Command  to  create  and change password files to be used by the RFB protocol (can be specified in
              the  $vncPasswdFile  variable).   /usr/bin/Xtigervnc  The  real  server.  Will   be   invoked   by
              tigervncserver.

AUTHOR

       2016  -  Modified for TigerVNC 1.7 by Joachim Falk (Joachim.falk@gmx.de) 2006 - Modified for vnc 4.1.2 by
       Joachim Falk (Joachim.falk@gmx.de) 1998 - Originally written by Marcus Brinkmann  (Marcus.Brinkmann@ruhr-
       uni-bochum.de) for the Debian GNU/Linux Distribution.

TigerVNC 1.7                                      Jan 5th, 2017                                     vnc.conf(5x)