systemd: Move networkd into separate modules

The systemd module was getting rather bloated.

nixos/modules/module-list.nix

@@ -414,6 +414,9 @@
   ./system/boot/stage-1.nix
   ./system/boot/stage-2.nix
   ./system/boot/systemd.nix
+  ./system/boot/networkd.nix
+  ./system/boot/resolved.nix
+  ./system/boot/timesyncd.nix
   ./system/boot/tmp.nix
   ./system/etc/etc.nix
   ./system/upstart/upstart.nix

nixos/modules/system/boot/networkd.nix

@@ -0,0 +1,663 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+with import ./systemd-unit-options.nix { inherit config lib; };
+
+let
+
+  cfg = config.systemd.network;
+
+  checkLink = checkUnitConfig "Link" [
+    (assertOnlyFields [
+      "Description" "Alias" "MACAddressPolicy" "MACAddress" "NamePolicy" "Name"
+      "MTUBytes" "BitsPerSecond" "Duplex" "WakeOnLan"
+    ])
+    (assertValueOneOf "MACAddressPolicy" ["persistent" "random"])
+    (assertMacAddress "MACAddress")
+    (assertValueOneOf "NamePolicy" [
+      "kernel" "database" "onboard" "slot" "path" "mac"
+    ])
+    (assertByteFormat "MTUBytes")
+    (assertByteFormat "BitsPerSecond")
+    (assertValueOneOf "Duplex" ["half" "full"])
+    (assertValueOneOf "WakeOnLan" ["phy" "magic" "off"])
+  ];
+
+  checkNetdev = checkUnitConfig "Netdev" [
+    (assertOnlyFields [
+      "Description" "Name" "Kind" "MTUBytes" "MACAddress"
+    ])
+    (assertHasField "Name")
+    (assertHasField "Kind")
+    (assertValueOneOf "Kind" [
+      "bridge" "bond" "vlan" "macvlan" "vxlan" "ipip"
+      "gre" "sit" "vti" "veth" "tun" "tap" "dummy"
+    ])
+    (assertByteFormat "MTUBytes")
+    (assertMacAddress "MACAddress")
+  ];
+
+  checkVlan = checkUnitConfig "VLAN" [
+    (assertOnlyFields ["Id"])
+    (assertRange "Id" 0 4094)
+  ];
+
+  checkMacvlan = checkUnitConfig "MACVLAN" [
+    (assertOnlyFields ["Mode"])
+    (assertValueOneOf "Mode" ["private" "vepa" "bridge" "passthru"])
+  ];
+
+  checkVxlan = checkUnitConfig "VXLAN" [
+    (assertOnlyFields ["Id" "Group" "TOS" "TTL" "MacLearning"])
+    (assertRange "TTL" 0 255)
+    (assertValueOneOf "MacLearning" boolValues)
+  ];
+
+  checkTunnel = checkUnitConfig "Tunnel" [
+    (assertOnlyFields ["Local" "Remote" "TOS" "TTL" "DiscoverPathMTU"])
+    (assertRange "TTL" 0 255)
+    (assertValueOneOf "DiscoverPathMTU" boolValues)
+  ];
+
+  checkPeer = checkUnitConfig "Peer" [
+    (assertOnlyFields ["Name" "MACAddress"])
+    (assertMacAddress "MACAddress")
+  ];
+
+  tunTapChecks = [
+    (assertOnlyFields ["OneQueue" "MultiQueue" "PacketInfo" "User" "Group"])
+    (assertValueOneOf "OneQueue" boolValues)
+    (assertValueOneOf "MultiQueue" boolValues)
+    (assertValueOneOf "PacketInfo" boolValues)
+  ];
+
+  checkTun = checkUnitConfig "Tun" tunTapChecks;
+
+  checkTap = checkUnitConfig "Tap" tunTapChecks;
+
+  checkBond = checkUnitConfig "Bond" [
+    (assertOnlyFields [
+      "Mode" "TransmitHashPolicy" "LACPTransmitRate" "MIIMonitorSec"
+      "UpDelaySec" "DownDelaySec"
+    ])
+    (assertValueOneOf "Mode" [
+      "balance-rr" "active-backup" "balance-xor"
+      "broadcast" "802.3ad" "balance-tlb" "balance-alb"
+    ])
+    (assertValueOneOf "TransmitHashPolicy" [
+      "layer2" "layer3+4" "layer2+3" "encap2+3" "802.3ad" "encap3+4"
+    ])
+    (assertValueOneOf "LACPTransmitRate" ["slow" "fast"])
+  ];
+
+  checkNetwork = checkUnitConfig "Network" [
+    (assertOnlyFields [
+      "Description" "DHCP" "DHCPServer" "IPv4LL" "IPv4LLRoute"
+      "LLMNR" "Domains" "Bridge" "Bond"
+    ])
+    (assertValueOneOf "DHCP" ["both" "none" "v4" "v6"])
+    (assertValueOneOf "DHCPServer" boolValues)
+    (assertValueOneOf "IPv4LL" boolValues)
+    (assertValueOneOf "IPv4LLRoute" boolValues)
+    (assertValueOneOf "LLMNR" boolValues)
+  ];
+
+  checkAddress = checkUnitConfig "Address" [
+    (assertOnlyFields ["Address" "Peer" "Broadcast" "Label"])
+    (assertHasField "Address")
+  ];
+
+  checkRoute = checkUnitConfig "Route" [
+    (assertOnlyFields ["Gateway" "Destination" "Metric"])
+    (assertHasField "Gateway")
+  ];
+
+  checkDhcp = checkUnitConfig "DHCP" [
+    (assertOnlyFields [
+      "UseDNS" "UseMTU" "SendHostname" "UseHostname" "UseDomains" "UseRoutes"
+      "CriticalConnections" "VendorClassIdentifier" "RequestBroadcast"
+      "RouteMetric"
+    ])
+    (assertValueOneOf "UseDNS" boolValues)
+    (assertValueOneOf "UseMTU" boolValues)
+    (assertValueOneOf "SendHostname" boolValues)
+    (assertValueOneOf "UseHostname" boolValues)
+    (assertValueOneOf "UseDomains" boolValues)
+    (assertValueOneOf "UseRoutes" boolValues)
+    (assertValueOneOf "CriticalConnections" boolValues)
+    (assertValueOneOf "RequestBroadcast" boolValues)
+  ];
+
+  commonNetworkOptions = {
+
+    enable = mkOption {
+      default = false;
+      type = types.bool;
+      description = ''
+        Whether to manage network configuration using <command>systemd-network</command>.
+      '';
+    };
+
+    matchConfig = mkOption {
+      default = {};
+      example = { Name = "eth0"; };
+      type = types.attrsOf unitOption;
+      description = ''
+        Each attribute in this set specifies an option in the
+        <literal>[Match]</literal> section of the unit.  See
+        <citerefentry><refentrytitle>systemd.link</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+        <citerefentry><refentrytitle>systemd.netdev</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+        <citerefentry><refentrytitle>systemd.network</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+        for details.
+      '';
+    };
+
+  };
+
+  linkOptions = commonNetworkOptions // {
+
+    linkConfig = mkOption {
+      default = {};
+      example = { MACAddress = "00:ff:ee:aa:cc:dd"; };
+      type = types.addCheck (types.attrsOf unitOption) checkLink;
+      description = ''
+        Each attribute in this set specifies an option in the
+        <literal>[Link]</literal> section of the unit.  See
+        <citerefentry><refentrytitle>systemd.link</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+  };
+
+  netdevOptions = commonNetworkOptions // {
+
+    netdevConfig = mkOption {
+      default = {};
+      example = { Name = "mybridge"; Kind = "bridge"; };
+      type = types.addCheck (types.attrsOf unitOption) checkNetdev;
+      description = ''
+        Each attribute in this set specifies an option in the
+        <literal>[Netdev]</literal> section of the unit.  See
+        <citerefentry><refentrytitle>systemd.netdev</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+    vlanConfig = mkOption {
+      default = {};
+      example = { Id = "4"; };
+      type = types.addCheck (types.attrsOf unitOption) checkVlan;
+      description = ''
+        Each attribute in this set specifies an option in the
+        <literal>[VLAN]</literal> section of the unit.  See
+        <citerefentry><refentrytitle>systemd.netdev</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+    macvlanConfig = mkOption {
+      default = {};
+      example = { Mode = "private"; };
+      type = types.addCheck (types.attrsOf unitOption) checkMacvlan;
+      description = ''
+        Each attribute in this set specifies an option in the
+        <literal>[MACVLAN]</literal> section of the unit.  See
+        <citerefentry><refentrytitle>systemd.netdev</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+    vxlanConfig = mkOption {
+      default = {};
+      example = { Id = "4"; };
+      type = types.addCheck (types.attrsOf unitOption) checkVxlan;
+      description = ''
+        Each attribute in this set specifies an option in the
+        <literal>[VXLAN]</literal> section of the unit.  See
+        <citerefentry><refentrytitle>systemd.netdev</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+    tunnelConfig = mkOption {
+      default = {};
+      example = { Remote = "192.168.1.1"; };
+      type = types.addCheck (types.attrsOf unitOption) checkTunnel;
+      description = ''
+        Each attribute in this set specifies an option in the
+        <literal>[Tunnel]</literal> section of the unit.  See
+        <citerefentry><refentrytitle>systemd.netdev</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+    peerConfig = mkOption {
+      default = {};
+      example = { Name = "veth2"; };
+      type = types.addCheck (types.attrsOf unitOption) checkPeer;
+      description = ''
+        Each attribute in this set specifies an option in the
+        <literal>[Peer]</literal> section of the unit.  See
+        <citerefentry><refentrytitle>systemd.netdev</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+    tunConfig = mkOption {
+      default = {};
+      example = { User = "openvpn"; };
+      type = types.addCheck (types.attrsOf unitOption) checkTun;
+      description = ''
+        Each attribute in this set specifies an option in the
+        <literal>[Tun]</literal> section of the unit.  See
+        <citerefentry><refentrytitle>systemd.netdev</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+    tapConfig = mkOption {
+      default = {};
+      example = { User = "openvpn"; };
+      type = types.addCheck (types.attrsOf unitOption) checkTap;
+      description = ''
+        Each attribute in this set specifies an option in the
+        <literal>[Tap]</literal> section of the unit.  See
+        <citerefentry><refentrytitle>systemd.netdev</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+    bondConfig = mkOption {
+      default = {};
+      example = { Mode = "802.3ad"; };
+      type = types.addCheck (types.attrsOf unitOption) checkBond;
+      description = ''
+        Each attribute in this set specifies an option in the
+        <literal>[Bond]</literal> section of the unit.  See
+        <citerefentry><refentrytitle>systemd.netdev</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+  };
+
+  addressOptions = {
+
+    addressConfig = mkOption {
+      default = {};
+      example = { Address = "192.168.0.100/24"; };
+      type = types.addCheck (types.attrsOf unitOption) checkAddress;
+      description = ''
+        Each attribute in this set specifies an option in the
+        <literal>[Address]</literal> section of the unit.  See
+        <citerefentry><refentrytitle>systemd.network</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+  };
+
+  routeOptions = {
+
+    routeConfig = mkOption {
+      default = {};
+      example = { Gateway = "192.168.0.1"; };
+      type = types.addCheck (types.attrsOf unitOption) checkRoute;
+      description = ''
+        Each attribute in this set specifies an option in the
+        <literal>[Route]</literal> section of the unit.  See
+        <citerefentry><refentrytitle>systemd.network</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+  };
+
+  networkOptions = commonNetworkOptions // {
+
+    networkConfig = mkOption {
+      default = {};
+      example = { Description = "My Network"; };
+      type = types.addCheck (types.attrsOf unitOption) checkNetwork;
+      description = ''
+        Each attribute in this set specifies an option in the
+        <literal>[Network]</literal> section of the unit.  See
+        <citerefentry><refentrytitle>systemd.network</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+    dhcpConfig = mkOption {
+      default = {};
+      example = { UseDNS = true; UseRoutes = true; };
+      type = types.addCheck (types.attrsOf unitOption) checkDhcp;
+      description = ''
+        Each attribute in this set specifies an option in the
+        <literal>[DHCP]</literal> section of the unit.  See
+        <citerefentry><refentrytitle>systemd.network</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+    name = mkOption {
+      type = types.nullOr types.str;
+      default = null;
+      description = ''
+        The name of the network interface to match against.
+      '';
+    };
+
+    DHCP = mkOption {
+      type = types.nullOr types.str;
+      default = null;
+      description = ''
+        Whether to enable DHCP on the interfaces matched.
+      '';
+    };
+
+    domains = mkOption {
+      type = types.nullOr (types.listOf types.str);
+      default = null;
+      description = ''
+        A list of domains to pass to the network config.
+      '';
+    };
+
+    address = mkOption {
+      default = [ ];
+      type = types.listOf types.str;
+      description = ''
+        A list of addresses to be added to the network section of the
+        unit.  See <citerefentry><refentrytitle>systemd.network</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+    gateway = mkOption {
+      default = [ ];
+      type = types.listOf types.str;
+      description = ''
+        A list of gateways to be added to the network section of the
+        unit.  See <citerefentry><refentrytitle>systemd.network</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+    dns = mkOption {
+      default = [ ];
+      type = types.listOf types.str;
+      description = ''
+        A list of dns servers to be added to the network section of the
+        unit.  See <citerefentry><refentrytitle>systemd.network</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+    ntp = mkOption {
+      default = [ ];
+      type = types.listOf types.str;
+      description = ''
+        A list of ntp servers to be added to the network section of the
+        unit.  See <citerefentry><refentrytitle>systemd.network</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+    vlan = mkOption {
+      default = [ ];
+      type = types.listOf types.str;
+      description = ''
+        A list of vlan interfaces to be added to the network section of the
+        unit.  See <citerefentry><refentrytitle>systemd.network</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+    macvlan = mkOption {
+      default = [ ];
+      type = types.listOf types.str;
+      description = ''
+        A list of macvlan interfaces to be added to the network section of the
+        unit.  See <citerefentry><refentrytitle>systemd.network</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+    vxlan = mkOption {
+      default = [ ];
+      type = types.listOf types.str;
+      description = ''
+        A list of vxlan interfaces to be added to the network section of the
+        unit.  See <citerefentry><refentrytitle>systemd.network</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+    tunnel = mkOption {
+      default = [ ];
+      type = types.listOf types.str;
+      description = ''
+        A list of tunnel interfaces to be added to the network section of the
+        unit.  See <citerefentry><refentrytitle>systemd.network</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+    addresses = mkOption {
+      default = [ ];
+      type = types.listOf types.optionSet;
+      options = [ addressOptions ];
+      description = ''
+        A list of address sections to be added to the unit.  See
+        <citerefentry><refentrytitle>systemd.network</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+    routes = mkOption {
+      default = [ ];
+      type = types.listOf types.optionSet;
+      options = [ routeOptions ];
+      description = ''
+        A list of route sections to be added to the unit.  See
+        <citerefentry><refentrytitle>systemd.network</refentrytitle>
+        <manvolnum>5</manvolnum></citerefentry> for details.
+      '';
+    };
+
+  };
+
+  networkConfig = { name, config, ... }: {
+    config = {
+      matchConfig = optionalAttrs (config.name != null) {
+        Name = config.name;
+      };
+      networkConfig = optionalAttrs (config.DHCP != null) {
+        DHCP = config.DHCP;
+      } // optionalAttrs (config.domains != null) {
+        Domains = concatStringsSep " " config.domains;
+      };
+    };
+  };
+
+  linkToUnit = name: def:
+    { inherit (def) enable;
+      text = commonMatchText def +
+        ''
+          [Link]
+          ${attrsToSection def.linkConfig}
+        '';
+    };
+
+  netdevToUnit = name: def:
+    { inherit (def) enable;
+      text = commonMatchText def +
+        ''
+          [NetDev]
+          ${attrsToSection def.netdevConfig}
+
+          ${optionalString (def.vlanConfig != { }) ''
+            [VLAN]
+            ${attrsToSection def.vlanConfig}
+
+          ''}
+          ${optionalString (def.macvlanConfig != { }) ''
+            [MACVLAN]
+            ${attrsToSection def.macvlanConfig}
+
+          ''}
+          ${optionalString (def.vxlanConfig != { }) ''
+            [VXLAN]
+            ${attrsToSection def.vxlanConfig}
+
+          ''}
+          ${optionalString (def.tunnelConfig != { }) ''
+            [Tunnel]
+            ${attrsToSection def.tunnelConfig}
+
+          ''}
+          ${optionalString (def.peerConfig != { }) ''
+            [Peer]
+            ${attrsToSection def.peerConfig}
+
+          ''}
+          ${optionalString (def.tunConfig != { }) ''
+            [Tun]
+            ${attrsToSection def.tunConfig}
+
+          ''}
+          ${optionalString (def.tapConfig != { }) ''
+            [Tap]
+            ${attrsToSection def.tapConfig}
+
+          ''}
+          ${optionalString (def.bondConfig != { }) ''
+            [Bond]
+            ${attrsToSection def.bondConfig}
+
+          ''}
+        '';
+    };
+
+  networkToUnit = name: def:
+    { inherit (def) enable;
+      text = commonMatchText def +
+        ''
+          [Network]
+          ${attrsToSection def.networkConfig}
+          ${concatStringsSep "\n" (map (s: "Address=${s}") def.address)}
+          ${concatStringsSep "\n" (map (s: "Gateway=${s}") def.gateway)}
+          ${concatStringsSep "\n" (map (s: "DNS=${s}") def.dns)}
+          ${concatStringsSep "\n" (map (s: "NTP=${s}") def.ntp)}
+          ${concatStringsSep "\n" (map (s: "VLAN=${s}") def.vlan)}
+          ${concatStringsSep "\n" (map (s: "MACVLAN=${s}") def.macvlan)}
+          ${concatStringsSep "\n" (map (s: "VXLAN=${s}") def.vxlan)}
+          ${concatStringsSep "\n" (map (s: "Tunnel=${s}") def.tunnel)}
+
+          ${optionalString (def.dhcpConfig != { }) ''
+            [DHCP]
+            ${attrsToSection def.dhcpConfig}
+
+          ''}
+          ${flip concatMapStrings def.addresses (x: ''
+            [Address]
+            ${attrsToSection x.addressConfig}
+
+          '')}
+          ${flip concatMapStrings def.routes (x: ''
+            [Route]
+            ${attrsToSection x.routeConfig}
+
+          '')}
+        '';
+    };
+
+in
+
+{
+
+  options = {
+
+    systemd.network.enable = mkOption {
+      default = false;
+      type = types.bool;
+      description = ''
+        Whether to enable networkd or not.
+      '';
+    };
+
+    systemd.network.links = mkOption {
+      default = {};
+      type = types.attrsOf types.optionSet;
+      options = [ linkOptions ];
+      description = "Definition of systemd network links.";
+    };
+
+    systemd.network.netdevs = mkOption {
+      default = {};
+      type = types.attrsOf types.optionSet;
+      options = [ netdevOptions ];
+      description = "Definition of systemd network devices.";
+    };
+
+    systemd.network.networks = mkOption {
+      default = {};
+      type = types.attrsOf types.optionSet;
+      options = [ networkOptions networkConfig ];
+      description = "Definition of systemd networks.";
+    };
+
+    systemd.network.units = mkOption {
+      description = "Definition of networkd units.";
+      default = {};
+      type = types.attrsOf types.optionSet;
+      options = { name, config, ... }:
+        { options = concreteUnitOptions;
+          config = {
+            unit = mkDefault (makeUnit name config);
+          };
+        };
+    };
+
+  };
+
+  config = mkIf config.systemd.network.enable {
+
+    systemd.network.units =
+      mapAttrs' (n: v: nameValuePair "${n}.link" (linkToUnit n v)) cfg.links
+      // mapAttrs' (n: v: nameValuePair "${n}.netdev" (netdevToUnit n v)) cfg.netdevs
+      // mapAttrs' (n: v: nameValuePair "${n}.network" (networkToUnit n v)) cfg.networks;
+
+    users.extraUsers.systemd-network.uid = config.ids.uids.systemd-network;
+    users.extraGroups.systemd-network.gid = config.ids.gids.systemd-network;
+
+    systemd.services.systemd-networkd = {
+      wantedBy = [ "multi-user.target" ];
+      before = [ "network-interfaces.target" ];
+      restartTriggers = [ config.environment.etc."systemd/network".source ];
+    };
+
+    systemd.services.systemd-networkd-wait-online = {
+      before = [ "network-online.target" "ip-up.target" ];
+      wantedBy = [ "network-online.target" "ip-up.target" ];
+    };
+
+    systemd.services."systemd-network-wait-online@" = {
+      description = "Wait for Network Interface %I to be Configured";
+      conflicts = [ "shutdown.target" ];
+      requisite = [ "systemd-networkd.service" ];
+      after = [ "systemd-networkd.service" ];
+      serviceConfig = {
+        Type = "oneshot";
+        RemainAfterExit = true;
+        ExecStart = "${config.systemd.package}/lib/systemd/systemd-networkd-wait-online -i %I";
+      };
+    };
+
+    services.resolved.enable = mkDefault true;
+    services.timesyncd.enable = mkDefault config.services.ntp.enable;
+
+  };
+
+}

nixos/modules/system/boot/resolved.nix

@@ -0,0 +1,36 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+{
+
+  options = {
+
+    services.resolved.enable = mkOption {
+      default = false;
+      type = types.bool;
+      description = ''
+        Whether to enable the systemd DNS resolver daemon.
+      '';
+    };
+
+  };
+
+  config = mkIf config.services.resolved.enable {
+
+    systemd.services.systemd-resolved = {
+      wantedBy = [ "multi-user.target" ];
+      restartTriggers = [ config.environment.etc."systemd/resolved.conf".source ];
+    };
+
+    environment.etc."systemd/resolved.conf".text = ''
+      [Resolve]
+      DNS=${concatStringsSep " " config.networking.nameservers}
+    '';
+
+    users.extraUsers.systemd-resolve.uid = config.ids.uids.systemd-resolve;
+    users.extraGroups.systemd-resolve.gid = config.ids.gids.systemd-resolve;
+
+  };
+
+}

nixos/modules/system/boot/systemd-unit-options.nix

@@ -62,126 +62,7 @@ let
     ])
   ];
 
-  checkLink = checkUnitConfig "Link" [
+in rec {
-    (assertOnlyFields [
-      "Description" "Alias" "MACAddressPolicy" "MACAddress" "NamePolicy" "Name"
-      "MTUBytes" "BitsPerSecond" "Duplex" "WakeOnLan"
-    ])
-    (assertValueOneOf "MACAddressPolicy" ["persistent" "random"])
-    (assertMacAddress "MACAddress")
-    (assertValueOneOf "NamePolicy" [
-      "kernel" "database" "onboard" "slot" "path" "mac"
-    ])
-    (assertByteFormat "MTUBytes")
-    (assertByteFormat "BitsPerSecond")
-    (assertValueOneOf "Duplex" ["half" "full"])
-    (assertValueOneOf "WakeOnLan" ["phy" "magic" "off"])
-  ];
-
-  checkNetdev = checkUnitConfig "Netdev" [
-    (assertOnlyFields [
-      "Description" "Name" "Kind" "MTUBytes" "MACAddress"
-    ])
-    (assertHasField "Name")
-    (assertHasField "Kind")
-    (assertValueOneOf "Kind" [
-      "bridge" "bond" "vlan" "macvlan" "vxlan" "ipip"
-      "gre" "sit" "vti" "veth" "tun" "tap" "dummy"
-    ])
-    (assertByteFormat "MTUBytes")
-    (assertMacAddress "MACAddress")
-  ];
-
-  checkVlan = checkUnitConfig "VLAN" [
-    (assertOnlyFields ["Id"])
-    (assertRange "Id" 0 4094)
-  ];
-
-  checkMacvlan = checkUnitConfig "MACVLAN" [
-    (assertOnlyFields ["Mode"])
-    (assertValueOneOf "Mode" ["private" "vepa" "bridge" "passthru"])
-  ];
-
-  checkVxlan = checkUnitConfig "VXLAN" [
-    (assertOnlyFields ["Id" "Group" "TOS" "TTL" "MacLearning"])
-    (assertRange "TTL" 0 255)
-    (assertValueOneOf "MacLearning" boolValues)
-  ];
-
-  checkTunnel = checkUnitConfig "Tunnel" [
-    (assertOnlyFields ["Local" "Remote" "TOS" "TTL" "DiscoverPathMTU"])
-    (assertRange "TTL" 0 255)
-    (assertValueOneOf "DiscoverPathMTU" boolValues)
-  ];
-
-  checkPeer = checkUnitConfig "Peer" [
-    (assertOnlyFields ["Name" "MACAddress"])
-    (assertMacAddress "MACAddress")
-  ];
-
-  tunTapChecks = [
-    (assertOnlyFields ["OneQueue" "MultiQueue" "PacketInfo" "User" "Group"])
-    (assertValueOneOf "OneQueue" boolValues)
-    (assertValueOneOf "MultiQueue" boolValues)
-    (assertValueOneOf "PacketInfo" boolValues)
-  ];
-
-  checkTun = checkUnitConfig "Tun" tunTapChecks;
-
-  checkTap = checkUnitConfig "Tap" tunTapChecks;
-
-  checkBond = checkUnitConfig "Bond" [
-    (assertOnlyFields [
-      "Mode" "TransmitHashPolicy" "LACPTransmitRate" "MIIMonitorSec"
-      "UpDelaySec" "DownDelaySec"
-    ])
-    (assertValueOneOf "Mode" [
-      "balance-rr" "active-backup" "balance-xor"
-      "broadcast" "802.3ad" "balance-tlb" "balance-alb"
-    ])
-    (assertValueOneOf "TransmitHashPolicy" [
-      "layer2" "layer3+4" "layer2+3" "encap2+3" "802.3ad" "encap3+4"
-    ])
-    (assertValueOneOf "LACPTransmitRate" ["slow" "fast"])
-  ];
-
-  checkNetwork = checkUnitConfig "Network" [
-    (assertOnlyFields [
-      "Description" "DHCP" "DHCPServer" "IPv4LL" "IPv4LLRoute"
-      "LLMNR" "Domains" "Bridge" "Bond"
-    ])
-    (assertValueOneOf "DHCP" ["both" "none" "v4" "v6"])
-    (assertValueOneOf "DHCPServer" boolValues)
-    (assertValueOneOf "IPv4LL" boolValues)
-    (assertValueOneOf "IPv4LLRoute" boolValues)
-    (assertValueOneOf "LLMNR" boolValues)
-  ];
-
-  checkAddress = checkUnitConfig "Address" [
-    (assertOnlyFields ["Address" "Peer" "Broadcast" "Label"])
-    (assertHasField "Address")
-  ];
-
-  checkRoute = checkUnitConfig "Route" [
-    (assertOnlyFields ["Gateway" "Destination" "Metric"])
-    (assertHasField "Gateway")
-  ];
-
-  checkDhcp = checkUnitConfig "DHCP" [
-    (assertOnlyFields [
-      "UseDNS" "UseMTU" "SendHostname" "UseHostname" "UseDomains" "UseRoutes"
-      "CriticalConnections" "VendorClassIdentifier" "RequestBroadcast"
-      "RouteMetric"
-    ])
-    (assertValueOneOf "UseDNS" boolValues)
-    (assertValueOneOf "UseMTU" boolValues)
-    (assertValueOneOf "SendHostname" boolValues)
-    (assertValueOneOf "UseHostname" boolValues)
-    (assertValueOneOf "UseDomains" boolValues)
-    (assertValueOneOf "UseRoutes" boolValues)
-    (assertValueOneOf "CriticalConnections" boolValues)
-    (assertValueOneOf "RequestBroadcast" boolValues)
-  ];
 
   unitOption = mkOptionType {
     name = "systemd option";
@@ -195,8 +76,6 @@ let
         else mergeOneOption loc defs';
   };
 
-in rec {
-
   sharedOptions = {
 
     enable = mkOption {
@@ -619,345 +498,4 @@ in rec {
 
   targetOptions = commonUnitOptions;
 
-  commonNetworkOptions = {
-
-    enable = mkOption {
-      default = true;
-      type = types.bool;
-      description = ''
-        If set to false, this unit will be a symlink to
-        /dev/null.
-      '';
-    };
-
-    matchConfig = mkOption {
-      default = {};
-      example = { Name = "eth0"; };
-      type = types.attrsOf unitOption;
-      description = ''
-        Each attribute in this set specifies an option in the
-        <literal>[Match]</literal> section of the unit.  See
-        <citerefentry><refentrytitle>systemd.link</refentrytitle><manvolnum>5</manvolnum></citerefentry>
-        <citerefentry><refentrytitle>systemd.netdev</refentrytitle><manvolnum>5</manvolnum></citerefentry>
-        <citerefentry><refentrytitle>systemd.network</refentrytitle><manvolnum>5</manvolnum></citerefentry>
-        for details.
-      '';
-    };
-
-  };
-
-  linkOptions = commonNetworkOptions // {
-
-    linkConfig = mkOption {
-      default = {};
-      example = { MACAddress = "00:ff:ee:aa:cc:dd"; };
-      type = types.addCheck (types.attrsOf unitOption) checkLink;
-      description = ''
-        Each attribute in this set specifies an option in the
-        <literal>[Link]</literal> section of the unit.  See
-        <citerefentry><refentrytitle>systemd.link</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-  };
-
-  netdevOptions = commonNetworkOptions // {
-
-    netdevConfig = mkOption {
-      default = {};
-      example = { Name = "mybridge"; Kind = "bridge"; };
-      type = types.addCheck (types.attrsOf unitOption) checkNetdev;
-      description = ''
-        Each attribute in this set specifies an option in the
-        <literal>[Netdev]</literal> section of the unit.  See
-        <citerefentry><refentrytitle>systemd.netdev</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-    vlanConfig = mkOption {
-      default = {};
-      example = { Id = "4"; };
-      type = types.addCheck (types.attrsOf unitOption) checkVlan;
-      description = ''
-        Each attribute in this set specifies an option in the
-        <literal>[VLAN]</literal> section of the unit.  See
-        <citerefentry><refentrytitle>systemd.netdev</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-    macvlanConfig = mkOption {
-      default = {};
-      example = { Mode = "private"; };
-      type = types.addCheck (types.attrsOf unitOption) checkMacvlan;
-      description = ''
-        Each attribute in this set specifies an option in the
-        <literal>[MACVLAN]</literal> section of the unit.  See
-        <citerefentry><refentrytitle>systemd.netdev</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-    vxlanConfig = mkOption {
-      default = {};
-      example = { Id = "4"; };
-      type = types.addCheck (types.attrsOf unitOption) checkVxlan;
-      description = ''
-        Each attribute in this set specifies an option in the
-        <literal>[VXLAN]</literal> section of the unit.  See
-        <citerefentry><refentrytitle>systemd.netdev</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-    tunnelConfig = mkOption {
-      default = {};
-      example = { Remote = "192.168.1.1"; };
-      type = types.addCheck (types.attrsOf unitOption) checkTunnel;
-      description = ''
-        Each attribute in this set specifies an option in the
-        <literal>[Tunnel]</literal> section of the unit.  See
-        <citerefentry><refentrytitle>systemd.netdev</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-    peerConfig = mkOption {
-      default = {};
-      example = { Name = "veth2"; };
-      type = types.addCheck (types.attrsOf unitOption) checkPeer;
-      description = ''
-        Each attribute in this set specifies an option in the
-        <literal>[Peer]</literal> section of the unit.  See
-        <citerefentry><refentrytitle>systemd.netdev</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-    tunConfig = mkOption {
-      default = {};
-      example = { User = "openvpn"; };
-      type = types.addCheck (types.attrsOf unitOption) checkTun;
-      description = ''
-        Each attribute in this set specifies an option in the
-        <literal>[Tun]</literal> section of the unit.  See
-        <citerefentry><refentrytitle>systemd.netdev</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-    tapConfig = mkOption {
-      default = {};
-      example = { User = "openvpn"; };
-      type = types.addCheck (types.attrsOf unitOption) checkTap;
-      description = ''
-        Each attribute in this set specifies an option in the
-        <literal>[Tap]</literal> section of the unit.  See
-        <citerefentry><refentrytitle>systemd.netdev</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-    bondConfig = mkOption {
-      default = {};
-      example = { Mode = "802.3ad"; };
-      type = types.addCheck (types.attrsOf unitOption) checkBond;
-      description = ''
-        Each attribute in this set specifies an option in the
-        <literal>[Bond]</literal> section of the unit.  See
-        <citerefentry><refentrytitle>systemd.netdev</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-  };
-
-  addressOptions = {
-
-    addressConfig = mkOption {
-      default = {};
-      example = { Address = "192.168.0.100/24"; };
-      type = types.addCheck (types.attrsOf unitOption) checkAddress;
-      description = ''
-        Each attribute in this set specifies an option in the
-        <literal>[Address]</literal> section of the unit.  See
-        <citerefentry><refentrytitle>systemd.network</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-  };
-
-  routeOptions = {
-
-    routeConfig = mkOption {
-      default = {};
-      example = { Gateway = "192.168.0.1"; };
-      type = types.addCheck (types.attrsOf unitOption) checkRoute;
-      description = ''
-        Each attribute in this set specifies an option in the
-        <literal>[Route]</literal> section of the unit.  See
-        <citerefentry><refentrytitle>systemd.network</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-  };
-
-  networkOptions = commonNetworkOptions // {
-
-    networkConfig = mkOption {
-      default = {};
-      example = { Description = "My Network"; };
-      type = types.addCheck (types.attrsOf unitOption) checkNetwork;
-      description = ''
-        Each attribute in this set specifies an option in the
-        <literal>[Network]</literal> section of the unit.  See
-        <citerefentry><refentrytitle>systemd.network</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-    dhcpConfig = mkOption {
-      default = {};
-      example = { UseDNS = true; UseRoutes = true; };
-      type = types.addCheck (types.attrsOf unitOption) checkDhcp;
-      description = ''
-        Each attribute in this set specifies an option in the
-        <literal>[DHCP]</literal> section of the unit.  See
-        <citerefentry><refentrytitle>systemd.network</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-    name = mkOption {
-      type = types.nullOr types.str;
-      default = null;
-      description = ''
-        The name of the network interface to match against.
-      '';
-    };
-
-    DHCP = mkOption {
-      type = types.nullOr types.str;
-      default = null;
-      description = ''
-        Whether to enable DHCP on the interfaces matched.
-      '';
-    };
-
-    domains = mkOption {
-      type = types.nullOr (types.listOf types.str);
-      default = null;
-      description = ''
-        A list of domains to pass to the network config.
-      '';
-    };
-
-    address = mkOption {
-      default = [ ];
-      type = types.listOf types.str;
-      description = ''
-        A list of addresses to be added to the network section of the
-        unit.  See <citerefentry><refentrytitle>systemd.network</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-    gateway = mkOption {
-      default = [ ];
-      type = types.listOf types.str;
-      description = ''
-        A list of gateways to be added to the network section of the
-        unit.  See <citerefentry><refentrytitle>systemd.network</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-    dns = mkOption {
-      default = [ ];
-      type = types.listOf types.str;
-      description = ''
-        A list of dns servers to be added to the network section of the
-        unit.  See <citerefentry><refentrytitle>systemd.network</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-    ntp = mkOption {
-      default = [ ];
-      type = types.listOf types.str;
-      description = ''
-        A list of ntp servers to be added to the network section of the
-        unit.  See <citerefentry><refentrytitle>systemd.network</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-    vlan = mkOption {
-      default = [ ];
-      type = types.listOf types.str;
-      description = ''
-        A list of vlan interfaces to be added to the network section of the
-        unit.  See <citerefentry><refentrytitle>systemd.network</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-    macvlan = mkOption {
-      default = [ ];
-      type = types.listOf types.str;
-      description = ''
-        A list of macvlan interfaces to be added to the network section of the
-        unit.  See <citerefentry><refentrytitle>systemd.network</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-    vxlan = mkOption {
-      default = [ ];
-      type = types.listOf types.str;
-      description = ''
-        A list of vxlan interfaces to be added to the network section of the
-        unit.  See <citerefentry><refentrytitle>systemd.network</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-    tunnel = mkOption {
-      default = [ ];
-      type = types.listOf types.str;
-      description = ''
-        A list of tunnel interfaces to be added to the network section of the
-        unit.  See <citerefentry><refentrytitle>systemd.network</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-    addresses = mkOption {
-      default = [ ];
-      type = types.listOf types.optionSet;
-      options = [ addressOptions ];
-      description = ''
-        A list of address sections to be added to the unit.  See
-        <citerefentry><refentrytitle>systemd.network</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-    routes = mkOption {
-      default = [ ];
-      type = types.listOf types.optionSet;
-      options = [ routeOptions ];
-      description = ''
-        A list of route sections to be added to the unit.  See
-        <citerefentry><refentrytitle>systemd.network</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry> for details.
-      '';
-    };
-
-  };
-
 }

nixos/modules/system/boot/systemd.nix

@@ -301,19 +301,6 @@ let
     };
   };
 
-  networkConfig = { name, config, ... }: {
-    config = {
-      matchConfig = optionalAttrs (config.name != null) {
-        Name = config.name;
-      };
-      networkConfig = optionalAttrs (config.DHCP != null) {
-        DHCP = config.DHCP;
-      } // optionalAttrs (config.domains != null) {
-        Domains = concatStringsSep " " config.domains;
-      };
-    };
-  };
-
   toOption = x:
     if x == true then "true"
     else if x == false then "false"
@@ -412,98 +399,6 @@ let
       ${attrsToSection def.matchConfig}
     '';
 
-  linkToUnit = name: def:
-    { inherit (def) enable;
-      text = commonMatchText def +
-        ''
-          [Link]
-          ${attrsToSection def.linkConfig}
-        '';
-    };
-
-  netdevToUnit = name: def:
-    { inherit (def) enable;
-      text = commonMatchText def +
-        ''
-          [NetDev]
-          ${attrsToSection def.netdevConfig}
-
-          ${optionalString (def.vlanConfig != { }) ''
-            [VLAN]
-            ${attrsToSection def.vlanConfig}
-
-          ''}
-          ${optionalString (def.macvlanConfig != { }) ''
-            [MACVLAN]
-            ${attrsToSection def.macvlanConfig}
-
-          ''}
-          ${optionalString (def.vxlanConfig != { }) ''
-            [VXLAN]
-            ${attrsToSection def.vxlanConfig}
-
-          ''}
-          ${optionalString (def.tunnelConfig != { }) ''
-            [Tunnel]
-            ${attrsToSection def.tunnelConfig}
-
-          ''}
-          ${optionalString (def.peerConfig != { }) ''
-            [Peer]
-            ${attrsToSection def.peerConfig}
-
-          ''}
-          ${optionalString (def.tunConfig != { }) ''
-            [Tun]
-            ${attrsToSection def.tunConfig}
-
-          ''}
-          ${optionalString (def.tapConfig != { }) ''
-            [Tap]
-            ${attrsToSection def.tapConfig}
-
-          ''}
-          ${optionalString (def.bondConfig != { }) ''
-            [Bond]
-            ${attrsToSection def.bondConfig}
-
-          ''}
-        '';
-    };
-
-  networkToUnit = name: def:
-    { inherit (def) enable;
-      text = commonMatchText def +
-        ''
-          [Network]
-          ${attrsToSection def.networkConfig}
-          ${concatStringsSep "\n" (map (s: "Address=${s}") def.address)}
-          ${concatStringsSep "\n" (map (s: "Gateway=${s}") def.gateway)}
-          ${concatStringsSep "\n" (map (s: "DNS=${s}") def.dns)}
-          ${concatStringsSep "\n" (map (s: "NTP=${s}") def.ntp)}
-          ${concatStringsSep "\n" (map (s: "VLAN=${s}") def.vlan)}
-          ${concatStringsSep "\n" (map (s: "MACVLAN=${s}") def.macvlan)}
-          ${concatStringsSep "\n" (map (s: "VXLAN=${s}") def.vxlan)}
-          ${concatStringsSep "\n" (map (s: "Tunnel=${s}") def.tunnel)}
-
-          ${optionalString (def.dhcpConfig != { }) ''
-            [DHCP]
-            ${attrsToSection def.dhcpConfig}
-
-          ''}
-          ${flip concatMapStrings def.addresses (x: ''
-            [Address]
-            ${attrsToSection x.addressConfig}
-
-          '')}
-          ${flip concatMapStrings def.routes (x: ''
-            [Route]
-            ${attrsToSection x.routeConfig}
-
-          '')}
-        '';
-    };
-
   generateUnits = type: units: upstreamUnits: upstreamWants:
     pkgs.runCommand "${type}-units" { preferLocalBuild = true; } ''
       mkdir -p $out
@@ -683,47 +578,6 @@ in
       '';
     };
 
-    systemd.network.enable = mkOption {
-      default = false;
-      type = types.bool;
-      description = ''
-        Whether to enable networkd or not.
-      '';
-    };
-
-    systemd.network.links = mkOption {
-      default = {};
-      type = types.attrsOf types.optionSet;
-      options = [ linkOptions ];
-      description = "Definition of systemd network links.";
-    };
-
-    systemd.network.netdevs = mkOption {
-      default = {};
-      type = types.attrsOf types.optionSet;
-      options = [ netdevOptions ];
-      description = "Definition of systemd network devices.";
-    };
-
-    systemd.network.networks = mkOption {
-      default = {};
-      type = types.attrsOf types.optionSet;
-      options = [ networkOptions networkConfig ];
-      description = "Definition of systemd networks.";
-    };
-
-    systemd.network.units = mkOption {
-      description = "Definition of networkd units.";
-      default = {};
-      type = types.attrsOf types.optionSet;
-      options = { name, config, ... }:
-        { options = concreteUnitOptions;
-          config = {
-            unit = mkDefault (makeUnit name config);
-          };
-        };
-    };
-
     systemd.defaultUnit = mkOption {
       default = "multi-user.target";
       type = types.str;
@@ -807,22 +661,6 @@ in
       '';
     };
 
-    services.resolved.enable = mkOption {
-      default = false;
-      type = types.bool;
-      description = ''
-        Enables the systemd dns resolver daemon.
-      '';
-    };
-
-    services.timesyncd.enable = mkOption {
-      default = false;
-      type = types.bool;
-      description = ''
-        Enables the systemd ntp client daemon.
-      '';
-    };
-
     systemd.tmpfiles.rules = mkOption {
       type = types.listOf types.str;
       default = [];
@@ -886,7 +724,7 @@ in
 
   ###### implementation
 
-  config = mkMerge [ {
+  config = {
 
     warnings = concatLists (mapAttrsToList (name: service:
       optional (service.serviceConfig.Type or "" == "oneshot" && service.serviceConfig.Restart or "no" != "no")
@@ -899,6 +737,7 @@ in
     environment.etc."systemd/system".source =
       generateUnits "system" cfg.units upstreamSystemUnits upstreamSystemWants;
 
+    # FIXME: move to networkd.nix.
     environment.etc."systemd/network".source =
       generateUnits "network" cfg.network.units [] [];
 
@@ -979,11 +818,6 @@ in
                    (v: let n = escapeSystemdPath v.where;
                        in nameValuePair "${n}.automount" (automountToUnit n v)) cfg.automounts);
 
-    systemd.network.units =
-      mapAttrs' (n: v: nameValuePair "${n}.link" (linkToUnit n v)) cfg.network.links
-      // mapAttrs' (n: v: nameValuePair "${n}.netdev" (netdevToUnit n v)) cfg.network.netdevs
-      // mapAttrs' (n: v: nameValuePair "${n}.network" (networkToUnit n v)) cfg.network.networks;
-
     systemd.user.units =
          mapAttrs' (n: v: nameValuePair "${n}.service" (serviceToUnit n v)) cfg.user.services
       // mapAttrs' (n: v: nameValuePair "${n}.socket"  (socketToUnit  n v)) cfg.user.sockets
@@ -1006,15 +840,6 @@ in
     users.extraUsers.systemd-journal-gateway.uid = config.ids.uids.systemd-journal-gateway;
     users.extraGroups.systemd-journal-gateway.gid = config.ids.gids.systemd-journal-gateway;
 
-    users.extraUsers.systemd-network.uid = config.ids.uids.systemd-network;
-    users.extraGroups.systemd-network.gid = config.ids.gids.systemd-network;
-
-    users.extraUsers.systemd-resolve.uid = config.ids.uids.systemd-resolve;
-    users.extraGroups.systemd-resolve.gid = config.ids.gids.systemd-resolve;
-
-    users.extraUsers.systemd-timesync.uid = config.ids.uids.systemd-timesync;
-    users.extraGroups.systemd-timesync.gid = config.ids.gids.systemd-timesync;
-
     # Generate timer units for all services that have a ‘startAt’ value.
     systemd.timers =
       mapAttrs (name: service:
@@ -1053,57 +878,6 @@ in
     systemd.services.systemd-remount-fs.restartIfChanged = false;
     systemd.services.systemd-journal-flush.restartIfChanged = false;
 
-  }
-  (mkIf config.systemd.network.enable {
-    systemd.services.systemd-networkd = {
-      wantedBy = [ "multi-user.target" ];
-      before = [ "network-interfaces.target" ];
-      restartTriggers = [ config.environment.etc."systemd/network".source ];
   };
 
-    systemd.services.systemd-networkd-wait-online = {
-      before = [ "network-online.target" "ip-up.target" ];
-      wantedBy = [ "network-online.target" "ip-up.target" ];
-    };
-
-    systemd.services."systemd-network-wait-online@" = {
-      description = "Wait for Network Interface %I to be Configured";
-      conflicts = [ "shutdown.target" ];
-      requisite = [ "systemd-networkd.service" ];
-      after = [ "systemd-networkd.service" ];
-      serviceConfig = {
-        Type = "oneshot";
-        RemainAfterExit = true;
-        ExecStart = "${config.systemd.package}/lib/systemd/systemd-networkd-wait-online -i %I";
-      };
-    };
-
-    services.resolved.enable = mkDefault true;
-    services.timesyncd.enable = mkDefault config.services.ntp.enable;
-  })
-  (mkIf config.services.resolved.enable {
-    systemd.services.systemd-resolved = {
-      wantedBy = [ "multi-user.target" ];
-      restartTriggers = [ config.environment.etc."systemd/resolved.conf".source ];
-    };
-
-    environment.etc."systemd/resolved.conf".text = ''
-      [Resolve]
-      DNS=${concatStringsSep " " config.networking.nameservers}
-    '';
-  })
-  (mkIf config.services.timesyncd.enable {
-    systemd.services.systemd-timesyncd = {
-      wantedBy = [ "sysinit.target" ];
-      restartTriggers = [ config.environment.etc."systemd/timesyncd.conf".source ];
-    };
-
-    environment.etc."systemd/timesyncd.conf".text = ''
-      [Time]
-      NTP=${concatStringsSep " " config.services.ntp.servers}
-    '';
-
-    systemd.services.ntpd.enable = false;
-  })
-  ];
 }

nixos/modules/system/boot/timesyncd.nix

@@ -0,0 +1,38 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+{
+
+  options = {
+
+    services.timesyncd.enable = mkOption {
+      default = false;
+      type = types.bool;
+      description = ''
+        Enables the systemd NTP client daemon.
+      '';
+    };
+
+  };
+
+  config = mkIf config.services.timesyncd.enable {
+
+    systemd.services.systemd-timesyncd = {
+      wantedBy = [ "sysinit.target" ];
+      restartTriggers = [ config.environment.etc."systemd/timesyncd.conf".source ];
+    };
+
+    environment.etc."systemd/timesyncd.conf".text = ''
+      [Time]
+      NTP=${concatStringsSep " " config.services.ntp.servers}
+    '';
+
+    systemd.services.ntpd.enable = false;
+
+    users.extraUsers.systemd-timesync.uid = config.ids.uids.systemd-timesync;
+    users.extraGroups.systemd-timesync.gid = config.ids.gids.systemd-timesync;
+
+  };
+
+}