nixpkgs/nixos/modules/services/x11/display-managers/lightdm.nix
Michael Weiss 1273f414a7 display-managers: Fix the xsession parameters
The xsession script was called with inconsistent (depending on the
display managers) and wrong parameters. The main reason for this where
the spaces the parameter syntax. In order to fix this the old syntax:
$1 = '<desktop-manager> + <window-manager>'
Will be replaced with a new syntax:
$1 = "<desktop-manager>+<window-manager>"

This assumes that neither "<desktop-manager>" nor "<window-manager>"
contain the "+" character but this shouldn't be a problem.

This patch also fixes the quoting by using double quotes (") instead of
single quotes (') [0].

Last but not least this'll add some comments for the better
understanding of the script.

[0]: https://specifications.freedesktop.org/desktop-entry-spec/latest/ar01s06.html
2017-04-28 22:00:14 +02:00

255 lines
7.5 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
xcfg = config.services.xserver;
dmcfg = xcfg.displayManager;
xEnv = config.systemd.services."display-manager".environment;
cfg = dmcfg.lightdm;
inherit (pkgs) stdenv lightdm writeScript writeText;
# lightdm runs with clearenv(), but we need a few things in the enviornment for X to startup
xserverWrapper = writeScript "xserver-wrapper"
''
#! ${pkgs.bash}/bin/bash
${concatMapStrings (n: "export ${n}=\"${getAttr n xEnv}\"\n") (attrNames xEnv)}
display=$(echo "$@" | xargs -n 1 | grep -P ^:\\d\$ | head -n 1 | sed s/^://)
if [ -z "$display" ]
then additionalArgs=":0 -logfile /var/log/X.0.log"
else additionalArgs="-logfile /var/log/X.$display.log"
fi
exec ${dmcfg.xserverBin} ${toString dmcfg.xserverArgs} $additionalArgs "$@"
'';
usersConf = writeText "users.conf"
''
[UserList]
minimum-uid=500
hidden-users=${concatStringsSep " " dmcfg.hiddenUsers}
hidden-shells=/run/current-system/sw/bin/nologin
'';
lightdmConf = writeText "lightdm.conf"
''
[LightDM]
${optionalString cfg.greeter.enable ''
greeter-user = ${config.users.extraUsers.lightdm.name}
greeters-directory = ${cfg.greeter.package}
''}
sessions-directory = ${dmcfg.session.desktops}
[Seat:*]
xserver-command = ${xserverWrapper}
session-wrapper = ${dmcfg.session.script}
${optionalString cfg.greeter.enable ''
greeter-session = ${cfg.greeter.name}
''}
${optionalString cfg.autoLogin.enable ''
autologin-user = ${cfg.autoLogin.user}
autologin-user-timeout = ${toString cfg.autoLogin.timeout}
autologin-session = ${defaultSessionName}
''}
${cfg.extraSeatDefaults}
'';
defaultSessionName =
let
dm = xcfg.desktopManager.default;
wm = xcfg.windowManager.default;
in dm + optionalString (wm != "none") ("+" + wm);
in
{
# Note: the order in which lightdm greeter modules are imported
# here determines the default: later modules (if enable) are
# preferred.
imports = [
./lightdm-greeters/gtk.nix
];
options = {
services.xserver.displayManager.lightdm = {
enable = mkOption {
type = types.bool;
default = false;
description = ''
Whether to enable lightdm as the display manager.
'';
};
greeter = {
enable = mkOption {
type = types.bool;
default = true;
description = ''
If set to false, run lightdm in greeterless mode. This only works if autologin
is enabled and autoLogin.timeout is zero.
'';
};
package = mkOption {
type = types.package;
description = ''
The LightDM greeter to login via. The package should be a directory
containing a .desktop file matching the name in the 'name' option.
'';
};
name = mkOption {
type = types.string;
description = ''
The name of a .desktop file in the directory specified
in the 'package' option.
'';
};
};
background = mkOption {
type = types.str;
default = "${pkgs.nixos-artwork}/share/artwork/gnome/Gnome_Dark.png";
description = ''
The background image or color to use.
'';
};
extraSeatDefaults = mkOption {
type = types.lines;
default = "";
example = ''
greeter-show-manual-login=true
'';
description = "Extra lines to append to SeatDefaults section.";
};
autoLogin = mkOption {
default = {};
description = ''
Configuration for automatic login.
'';
type = types.submodule {
options = {
enable = mkOption {
type = types.bool;
default = false;
description = ''
Automatically log in as the specified <option>autoLogin.user</option>.
'';
};
user = mkOption {
type = types.nullOr types.str;
default = null;
description = ''
User to be used for the automatic login.
'';
};
timeout = mkOption {
type = types.int;
default = 0;
description = ''
Show the greeter for this many seconds before automatic login occurs.
'';
};
};
};
};
};
};
config = mkIf cfg.enable {
assertions = [
{ assertion = cfg.autoLogin.enable -> cfg.autoLogin.user != null;
message = ''
LightDM auto-login requires services.xserver.displayManager.lightdm.autoLogin.user to be set
'';
}
{ assertion = cfg.autoLogin.enable -> elem defaultSessionName dmcfg.session.names;
message = ''
LightDM auto-login requires that services.xserver.desktopManager.default and
services.xserver.windowMananger.default are set to valid values. The current
default session: ${defaultSessionName} is not valid.
'';
}
{ assertion = !cfg.greeter.enable -> (cfg.autoLogin.enable && cfg.autoLogin.timeout == 0);
message = ''
LightDM can only run without greeter if automatic login is enabled and the timeout for it
is set to zero.
'';
}
];
services.xserver.displayManager.slim.enable = false;
services.xserver.displayManager.job = {
logsXsession = true;
# lightdm relaunches itself via just `lightdm`, so needs to be on the PATH
execCmd = ''
export PATH=${lightdm}/sbin:$PATH
exec ${lightdm}/sbin/lightdm --log-dir=/var/log --run-dir=/run
'';
};
environment.etc."lightdm/lightdm.conf".source = lightdmConf;
environment.etc."lightdm/users.conf".source = usersConf;
services.dbus.enable = true;
services.dbus.packages = [ lightdm ];
# lightdm uses the accounts daemon to rember language/window-manager per user
services.accounts-daemon.enable = true;
security.pam.services.lightdm = {
allowNullPassword = true;
startSession = true;
};
security.pam.services.lightdm-greeter = {
allowNullPassword = true;
startSession = true;
text = ''
auth required pam_env.so envfile=${config.system.build.pamEnvironment}
auth required pam_permit.so
account required pam_permit.so
password required pam_deny.so
session required pam_env.so envfile=${config.system.build.pamEnvironment}
session required pam_unix.so
session optional ${pkgs.systemd}/lib/security/pam_systemd.so
'';
};
security.pam.services.lightdm-autologin.text = ''
auth requisite pam_nologin.so
auth required pam_succeed_if.so uid >= 1000 quiet
auth required pam_permit.so
account include lightdm
password include lightdm
session include lightdm
'';
users.extraUsers.lightdm = {
createHome = true;
home = "/var/lib/lightdm-data";
group = "lightdm";
uid = config.ids.uids.lightdm;
};
users.extraGroups.lightdm.gid = config.ids.gids.lightdm;
services.xserver.tty = null; # We might start multiple X servers so let the tty increment themselves..
services.xserver.display = null; # We specify our own display (and logfile) in xserver-wrapper up there
};
}