nixpkgs/nixos/modules/services/system/dbus.nix
Eelco Dolstra 29027fd1e1 Rewrite ‘with pkgs.lib’ -> ‘with lib’
Using pkgs.lib on the spine of module evaluation is problematic
because the pkgs argument depends on the result of module
evaluation. To prevent an infinite recursion, pkgs and some of the
modules are evaluated twice, which is inefficient. Using ‘with lib’
prevents this problem.
2014-04-14 16:26:48 +02:00

161 lines
4.4 KiB
Nix

# D-Bus configuration and system bus daemon.
{ config, lib, pkgs, ... }:
with lib;
let
cfg = config.services.dbus;
homeDir = "/var/run/dbus";
configDir = pkgs.stdenv.mkDerivation {
name = "dbus-conf";
preferLocalBuild = true;
buildCommand = ''
ensureDir $out
cp -v ${pkgs.dbus_daemon}/etc/dbus-1/system.conf $out/system.conf
# !!! Hm, these `sed' calls are rather error-prone...
# Tell the daemon where the setuid wrapper around
# dbus-daemon-launch-helper lives.
sed -i $out/system.conf \
-e 's|<servicehelper>.*/libexec/dbus-daemon-launch-helper|<servicehelper>${config.security.wrapperDir}/dbus-daemon-launch-helper|'
# Add the system-services and system.d directories to the system
# bus search path.
sed -i $out/system.conf \
-e 's|<standard_system_servicedirs/>|${systemServiceDirs}|' \
-e 's|<includedir>system.d</includedir>|${systemIncludeDirs}|'
cp ${pkgs.dbus_daemon}/etc/dbus-1/session.conf $out/session.conf
# Add the services and session.d directories to the session bus
# search path.
sed -i $out/session.conf \
-e 's|<standard_session_servicedirs />|${sessionServiceDirs}&|' \
-e 's|<includedir>session.d</includedir>|${sessionIncludeDirs}|'
''; # */
};
systemServiceDirs = concatMapStrings
(d: "<servicedir>${d}/share/dbus-1/system-services</servicedir> ")
cfg.packages;
systemIncludeDirs = concatMapStrings
(d: "<includedir>${d}/etc/dbus-1/system.d</includedir> ")
cfg.packages;
sessionServiceDirs = concatMapStrings
(d: "<servicedir>${d}/share/dbus-1/services</servicedir> ")
cfg.packages;
sessionIncludeDirs = concatMapStrings
(d: "<includedir>${d}/etc/dbus-1/session.d</includedir> ")
cfg.packages;
in
{
###### interface
options = {
services.dbus = {
enable = mkOption {
type = types.bool;
default = true;
description = ''
Whether to start the D-Bus message bus daemon, which is
required by many other system services and applications.
'';
};
packages = mkOption {
type = types.listOf types.path;
default = [];
description = ''
Packages whose D-Bus configuration files should be included in
the configuration of the D-Bus system-wide message bus.
Specifically, every file in
<filename><replaceable>pkg</replaceable>/etc/dbus-1/system.d</filename>
is included.
'';
};
};
};
###### implementation
config = mkIf cfg.enable {
environment.systemPackages = [ pkgs.dbus_daemon pkgs.dbus_tools ];
environment.etc = singleton
{ source = configDir;
target = "dbus-1";
};
users.extraUsers.messagebus = {
uid = config.ids.uids.messagebus;
description = "D-Bus system message bus daemon user";
home = homeDir;
group = "messagebus";
};
users.extraGroups.messagebus.gid = config.ids.gids.messagebus;
# FIXME: these are copied verbatim from the dbus source tree. We
# should install and use the originals.
systemd.units."dbus.socket".text =
''
[Unit]
Description=D-Bus System Message Bus Socket
[Socket]
ListenStream=/var/run/dbus/system_bus_socket
'';
systemd.units."dbus.service".text =
''
[Unit]
Description=D-Bus System Message Bus
Requires=dbus.socket
[Service]
ExecStartPre=${pkgs.dbus_tools}/bin/dbus-uuidgen --ensure
ExecStartPre=-${pkgs.coreutils}/bin/rm -f /var/run/dbus/pid
ExecStart=${pkgs.dbus_daemon}/bin/dbus-daemon --system --address=systemd: --nofork --systemd-activation
ExecReload=${pkgs.dbus_tools}/bin/dbus-send --print-reply --system --type=method_call --dest=org.freedesktop.DBus / org.freedesktop.DBus.ReloadConfig
OOMScoreAdjust=-900
'';
security.setuidOwners = singleton
{ program = "dbus-daemon-launch-helper";
source = "${pkgs.dbus_daemon}/libexec/dbus-daemon-launch-helper";
owner = "root";
group = "messagebus";
setuid = true;
setgid = false;
permissions = "u+rx,g+rx,o-rx";
};
services.dbus.packages =
[ "/nix/var/nix/profiles/default"
config.system.path
];
environment.pathsToLink = [ "/etc/dbus-1" "/share/dbus-1" ];
};
}