nixpkgs/nixos/modules/services/networking/dnsmasq.nix
Peter Hoeg 0034f9e52c dnsmasq nixos: make sure it always runs
By default we only restart if the dnsmasq daemon fails but we introduce an
option to always keep it running.
2017-10-12 12:55:12 +08:00

120 lines
3 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
cfg = config.services.dnsmasq;
dnsmasq = pkgs.dnsmasq;
stateDir = "/var/lib/dnsmasq";
dnsmasqConf = pkgs.writeText "dnsmasq.conf" ''
dhcp-leasefile=${stateDir}/dnsmasq.leases
${optionalString cfg.resolveLocalQueries ''
conf-file=/etc/dnsmasq-conf.conf
resolv-file=/etc/dnsmasq-resolv.conf
''}
${flip concatMapStrings cfg.servers (server: ''
server=${server}
'')}
${cfg.extraConfig}
'';
in
{
###### interface
options = {
services.dnsmasq = {
enable = mkOption {
type = types.bool;
default = false;
description = ''
Whether to run dnsmasq.
'';
};
resolveLocalQueries = mkOption {
type = types.bool;
default = true;
description = ''
Whether dnsmasq should resolve local queries (i.e. add 127.0.0.1 to
/etc/resolv.conf).
'';
};
servers = mkOption {
type = types.listOf types.str;
default = [];
example = [ "8.8.8.8" "8.8.4.4" ];
description = ''
The DNS servers which dnsmasq should query.
'';
};
alwaysKeepRunning = mkOption {
type = types.bool;
default = false;
description = ''
If enabled, systemd will always respawn dnsmasq even if shut down manually. The default, disabled, will only restart it on error.
'';
};
extraConfig = mkOption {
type = types.lines;
default = "";
description = ''
Extra configuration directives that should be added to
<literal>dnsmasq.conf</literal>.
'';
};
};
};
###### implementation
config = mkIf config.services.dnsmasq.enable {
networking.nameservers =
optional cfg.resolveLocalQueries "127.0.0.1";
services.dbus.packages = [ dnsmasq ];
users.extraUsers = singleton {
name = "dnsmasq";
uid = config.ids.uids.dnsmasq;
description = "Dnsmasq daemon user";
};
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 ];
};
};
}