nixos/routedns: init

Signed-off-by: Jeroen Simonetti <jeroen@simonetti.nl>

nixos/modules/module-list.nix

@@ -884,6 +884,7 @@
   ./services/networking/redsocks.nix
   ./services/networking/resilio.nix
   ./services/networking/robustirc-bridge.nix
+  ./services/networking/routedns.nix
   ./services/networking/rpcbind.nix
   ./services/networking/rxe.nix
   ./services/networking/sabnzbd.nix

nixos/modules/services/networking/routedns.nix

@@ -0,0 +1,84 @@
+{ config
+, lib
+, pkgs
+, ...
+}:
+
+with lib;
+
+let
+  cfg = config.services.routedns;
+  settingsFormat = pkgs.formats.toml { };
+in
+{
+  options.services.routedns = {
+    enable = mkEnableOption "RouteDNS - DNS stub resolver, proxy and router";
+
+    settings = mkOption {
+      type = settingsFormat.type;
+      example = literalExpression ''
+        {
+          resolvers.cloudflare-dot = {
+            address = "1.1.1.1:853";
+            protocol = "dot";
+          };
+          groups.cloudflare-cached = {
+            type = "cache";
+            resolvers = ["cloudflare-dot"];
+          };
+          listeners.local-udp = {
+            address = "127.0.0.1:53";
+            protocol = "udp";
+            resolver = "cloudflare-cached";
+          };
+          listeners.local-tcp = {
+            address = "127.0.0.1:53";
+            protocol = "tcp";
+            resolver = "cloudflare-cached";
+          };
+        }
+      '';
+      description = ''
+        Configuration for RouteDNS, see <link xlink:href="https://github.com/folbricht/routedns/blob/master/doc/configuration.md"/>
+        for more information.
+      '';
+    };
+
+    configFile = mkOption {
+      default = settingsFormat.generate "routedns.toml" cfg.settings;
+      defaultText = "A RouteDNS configuration file automatically generated by values from services.routedns.*";
+      type = types.path;
+      example = literalExpression ''"''${pkgs.routedns}/cmd/routedns/example-config/use-case-1.toml"'';
+      description = "Path to RouteDNS TOML configuration file.";
+    };
+
+    package = mkOption {
+      default = pkgs.routedns;
+      defaultText = literalExpression "pkgs.routedns";
+      type = types.package;
+      description = "RouteDNS package to use.";
+    };
+  };
+
+  config = mkIf cfg.enable {
+    systemd.services.routedns = {
+      description = "RouteDNS - DNS stub resolver, proxy and router";
+      after = [ "network.target" ]; # in case a bootstrap resolver is used, this might fail a few times until the respective server is actually reachable
+      wantedBy = [ "multi-user.target" ];
+      wants = [ "network.target" ];
+      startLimitIntervalSec = 30;
+      startLimitBurst = 5;
+      serviceConfig = {
+        Restart = "on-failure";
+        RestartSec = "5s";
+        LimitNPROC = 512;
+        LimitNOFILE = 1048576;
+        DynamicUser = true;
+        AmbientCapabilities = "CAP_NET_BIND_SERVICE";
+        NoNewPrivileges = true;
+        ExecStart = "${getBin cfg.package}/bin/routedns -l 4 ${cfg.configFile}";
+      };
+    };
+  };
+  meta.maintainers = with maintainers; [ jsimonetti ];
+}