nixpkgs/nixos/modules/services/networking/dnsmasq.nix
Robert Kovacsics 2c00429560 nixos/dnsmasq: Use attrs instead of plain text config
This should make it easier to configure in multiple places, override
defaults, etc.
2022-12-04 23:08:37 +00:00

183 lines
5.2 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
cfg = config.services.dnsmasq;
dnsmasq = pkgs.dnsmasq;
stateDir = "/var/lib/dnsmasq";
# True values are just put as `name` instead of `name=true`, and false values
# are turned to comments (false values are expected to be overrides e.g.
# mkForce)
formatKeyValue =
name: value:
if value == true
then name
else if value == false
then "# setting `${name}` explicitly set to false"
else generators.mkKeyValueDefault { } "=" name value;
settingsFormat = pkgs.formats.keyValue {
mkKeyValue = formatKeyValue;
listsAsDuplicateKeys = true;
};
# Because formats.generate is outputting a file, we use of conf-file. Once
# `extraConfig` is deprecated we can just use
# `dnsmasqConf = format.generate "dnsmasq.conf" cfg.settings`
dnsmasqConf = pkgs.writeText "dnsmasq.conf" ''
conf-file=${settingsFormat.generate "dnsmasq.conf" cfg.settings}
${cfg.extraConfig}
'';
in
{
imports = [
(mkRenamedOptionModule [ "services" "dnsmasq" "servers" ] [ "services" "dnsmasq" "settings" "server" ])
];
###### interface
options = {
services.dnsmasq = {
enable = mkOption {
type = types.bool;
default = false;
description = lib.mdDoc ''
Whether to run dnsmasq.
'';
};
resolveLocalQueries = mkOption {
type = types.bool;
default = true;
description = lib.mdDoc ''
Whether dnsmasq should resolve local queries (i.e. add 127.0.0.1 to
/etc/resolv.conf).
'';
};
alwaysKeepRunning = mkOption {
type = types.bool;
default = false;
description = lib.mdDoc ''
If enabled, systemd will always respawn dnsmasq even if shut down manually. The default, disabled, will only restart it on error.
'';
};
settings = mkOption {
type = types.submodule {
freeformType = settingsFormat.type;
options.server = mkOption {
type = types.listOf types.str;
default = [ ];
example = [ "8.8.8.8" "8.8.4.4" ];
description = lib.mdDoc ''
The DNS servers which dnsmasq should query.
'';
};
};
default = { };
description = lib.mdDoc ''
Configuration of dnsmasq. Lists get added one value per line (empty
lists and false values don't get added, though false values get
turned to comments). Gets merged with
{
dhcp-leasefile = "${stateDir}/dnsmasq.leases";
conf-file = optional cfg.resolveLocalQueries "/etc/dnsmasq-conf.conf";
resolv-file = optional cfg.resolveLocalQueries "/etc/dnsmasq-resolv.conf";
}
'';
example = literalExpression ''
{
domain-needed = true;
dhcp-range = [ "192.168.0.2,192.168.0.254" ];
}
'';
};
extraConfig = mkOption {
type = types.lines;
default = "";
description = lib.mdDoc ''
Extra configuration directives that should be added to
`dnsmasq.conf`.
This option is deprecated, please use {option}`settings` instead.
'';
};
};
};
###### implementation
config = mkIf cfg.enable {
warnings = lib.optional (cfg.extraConfig != "") "Text based config is deprecated, dnsmasq now supports `services.dnsmasq.settings` for an attribute-set based config";
services.dnsmasq.settings = {
dhcp-leasefile = mkDefault "${stateDir}/dnsmasq.leases";
conf-file = mkDefault (optional cfg.resolveLocalQueries "/etc/dnsmasq-conf.conf");
resolv-file = mkDefault (optional cfg.resolveLocalQueries "/etc/dnsmasq-resolv.conf");
};
networking.nameservers =
optional cfg.resolveLocalQueries "127.0.0.1";
services.dbus.packages = [ dnsmasq ];
users.users.dnsmasq = {
isSystemUser = true;
group = "dnsmasq";
description = "Dnsmasq daemon user";
};
users.groups.dnsmasq = {};
networking.resolvconf = mkIf cfg.resolveLocalQueries {
useLocalResolver = mkDefault true;
extraConfig = ''
dnsmasq_conf=/etc/dnsmasq-conf.conf
dnsmasq_resolv=/etc/dnsmasq-resolv.conf
'';
};
systemd.services.dnsmasq = {
description = "Dnsmasq Daemon";
after = [ "network.target" "systemd-resolved.service" ];
wantedBy = [ "multi-user.target" ];
path = [ dnsmasq ];
preStart = ''
mkdir -m 755 -p ${stateDir}
touch ${stateDir}/dnsmasq.leases
chown -R dnsmasq ${stateDir}
touch /etc/dnsmasq-{conf,resolv}.conf
dnsmasq --test
'';
serviceConfig = {
Type = "dbus";
BusName = "uk.org.thekelleys.dnsmasq";
ExecStart = "${dnsmasq}/bin/dnsmasq -k --enable-dbus --user=dnsmasq -C ${dnsmasqConf}";
ExecReload = "${pkgs.coreutils}/bin/kill -HUP $MAINPID";
PrivateTmp = true;
ProtectSystem = true;
ProtectHome = true;
Restart = if cfg.alwaysKeepRunning then "always" else "on-failure";
};
restartTriggers = [ config.environment.etc.hosts.source ];
};
};
}