# This module implements a terminal service based on ‘x11vnc’. It # listens on port 5900 for VNC connections. It then presents a login # screen to the user. If the user successfully authenticates, x11vnc # checks to see if a X server is already running for that user. If # not, a X server (Xvfb) is started for that user. The Xvfb instances # persist across VNC sessions. { config, lib, pkgs, ... }: with lib; let # Wrap Xvfb to set some flags/variables. xvfbWrapper = pkgs.writeScriptBin "Xvfb" '' #! ${pkgs.stdenv.shell} export XKB_BINDIR=${pkgs.xorg.xkbcomp}/bin export XORG_DRI_DRIVER_PATH=${pkgs.mesa}/lib/dri exec ${pkgs.xorg.xorgserver}/bin/Xvfb "$@" -xkbdir ${pkgs.xkeyboard_config}/etc/X11/xkb ''; in { config = { services.xserver.enable = true; services.xserver.videoDrivers = []; # Enable KDM. Any display manager will do as long as it supports XDMCP. services.xserver.displayManager.kdm.enable = true; services.xserver.displayManager.kdm.enableXDMCP = true; services.xserver.displayManager.kdm.extraConfig = '' [General] # We're headless, so don't bother starting an X server. StaticServers= [Xdmcp] Xaccess=${pkgs.writeText "Xaccess" "localhost"} ''; systemd.sockets.terminal-server = { description = "Terminal Server Socket"; wantedBy = [ "sockets.target" ]; before = [ "multi-user.target" ]; socketConfig.Accept = true; socketConfig.ListenStream = 5900; }; systemd.services."terminal-server@" = { description = "Terminal Server"; path = [ xvfbWrapper pkgs.gawk pkgs.which pkgs.openssl pkgs.xorg.xauth pkgs.nettools pkgs.shadow pkgs.procps pkgs.utillinux pkgs.bash ]; environment.FD_GEOM = "1024x786x24"; environment.FD_XDMCP_IF = "127.0.0.1"; #environment.FIND_DISPLAY_OUTPUT = "/tmp/foo"; # to debug the "find display" script serviceConfig = { StandardInput = "socket"; StandardOutput = "socket"; StandardError = "journal"; ExecStart = "@${pkgs.x11vnc}/bin/x11vnc x11vnc -inetd -display WAIT:1024x786:cmd=FINDCREATEDISPLAY-Xvfb.xdmcp -unixpw -ssl SAVE"; # Don't kill the X server when the user quits the VNC # connection. FIXME: the X server should run in a # separate systemd session. KillMode = "process"; }; }; }; }