nixos/livekit: init, nixos/lk-jwt-service: init (#399627)

nixos/modules/module-list.nix

@@ -752,6 +752,7 @@
   ./services/matrix/dendrite.nix
   ./services/matrix/hebbot.nix
   ./services/matrix/hookshot.nix
+  ./services/matrix/lk-jwt-service.nix
   ./services/matrix/matrix-alertmanager.nix
   ./services/matrix/maubot.nix
   ./services/matrix/mautrix-meta.nix
@@ -1181,6 +1182,7 @@
   ./services/networking/lambdabot.nix
   ./services/networking/legit.nix
   ./services/networking/libreswan.nix
+  ./services/networking/livekit.nix
   ./services/networking/lldpd.nix
   ./services/networking/logmein-hamachi.nix
   ./services/networking/lokinet.nix

nixos/modules/services/matrix/lk-jwt-service.nix

@@ -0,0 +1,93 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+let
+  cfg = config.services.lk-jwt-service;
+in
+{
+  meta.maintainers = [ lib.maintainers.quadradical ];
+  options.services.lk-jwt-service = {
+    enable = lib.mkEnableOption "Enable lk-jwt-service";
+    package = lib.mkPackageOption pkgs "lk-jwt-service" { };
+
+    livekitUrl = lib.mkOption {
+      type = lib.types.strMatching "^wss?://.*";
+      example = "wss://example.com/livekit/sfu";
+      description = ''
+        The public websocket URL for livekit.
+        The proto needs to be either  `wss://` (recommended) or `ws://` (insecure).
+      '';
+    };
+
+    keyFile = lib.mkOption {
+      type = lib.types.path;
+      description = ''
+        Path to a file containing the credential mapping (`<keyname>: <secret>`) to access LiveKit.
+
+        Example:
+        ```
+          lk-jwt-service: f6lQGaHtM5HfgZjIcec3cOCRfiDqIine4CpZZnqdT5cE
+        ```
+
+        For more information, see <https://github.com/element-hq/lk-jwt-service#configuration>.
+      '';
+    };
+
+    port = lib.mkOption {
+      type = lib.types.port;
+      default = 8080;
+      description = "Port that lk-jwt-service should listen on.";
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    systemd.services.lk-jwt-service = {
+      description = "Minimal service to issue LiveKit JWTs for MatrixRTC";
+      documentation = [ "https://github.com/element-hq/lk-jwt-service" ];
+      wantedBy = [ "multi-user.target" ];
+      wants = [ "network-online.target" ];
+      after = [ "network-online.target" ];
+      environment = {
+        LIVEKIT_URL = cfg.livekitUrl;
+        LIVEKIT_JWT_PORT = toString cfg.port;
+        LIVEKIT_KEY_FILE = "/run/credentials/lk-jwt-service.service/livekit-secrets";
+      };
+
+      serviceConfig = {
+        LoadCredential = [ "livekit-secrets:${cfg.keyFile}" ];
+        ExecStart = lib.getExe cfg.package;
+        DynamicUser = true;
+        LockPersonality = true;
+        MemoryDenyWriteExecute = true;
+        ProtectClock = true;
+        ProtectControlGroups = true;
+        ProtectHostname = true;
+        ProtectKernelLogs = true;
+        ProtectKernelModules = true;
+        ProtectKernelTunables = true;
+        PrivateDevices = true;
+        PrivateMounts = true;
+        PrivateUsers = true;
+        RestrictAddressFamilies = [
+          "AF_INET"
+          "AF_INET6"
+        ];
+        RestrictNamespaces = true;
+        RestrictRealtime = true;
+        ProtectHome = true;
+        SystemCallArchitectures = "native";
+        SystemCallFilter = [
+          "@system-service"
+          "~@privileged"
+          "~@resources"
+        ];
+        Restart = "on-failure";
+        RestartSec = 5;
+        UMask = "077";
+      };
+    };
+  };
+}

nixos/modules/services/networking/livekit.nix

@@ -0,0 +1,141 @@
+{
+  config,
+  lib,
+  pkgs,
+  utils,
+  ...
+}:
+let
+  cfg = config.services.livekit;
+  format = pkgs.formats.json { };
+in
+{
+  meta.maintainers = with lib.maintainers; [ quadradical ];
+  options.services.livekit = {
+    enable = lib.mkEnableOption "Enable the livekit server";
+    package = lib.mkPackageOption pkgs "livekit" { };
+
+    keyFile = lib.mkOption {
+      type = lib.types.path;
+      description = ''
+        LiveKit key file holding one or multiple application secrets. Use `livekit-server generate-keys` to generate a random key name and secret.
+
+        The file should have the format `<keyname>: <secret>`. Example:
+        ```
+          lk-jwt-service: f6lQGaHtM5HfgZjIcec3cOCRfiDqIine4CpZZnqdT5cE
+        ```
+
+        Individual key/secret pairs need to be passed to clients to connect to this instance.
+      '';
+    };
+
+    openFirewall = lib.mkOption {
+      type = lib.types.bool;
+      default = false;
+      description = "Opens port range for LiveKit on the firewall.";
+    };
+
+    settings = lib.mkOption {
+      type = lib.types.submodule {
+        freeformType = format.type;
+        options = {
+          port = lib.mkOption {
+            type = lib.types.port;
+            default = 7880;
+            description = "Main TCP port for RoomService and RTC endpoint.";
+          };
+
+          rtc = {
+            port_range_start = lib.mkOption {
+              type = lib.types.int;
+              default = 50000;
+              description = "Start of UDP port range for WebRTC";
+            };
+
+            port_range_end = lib.mkOption {
+              type = lib.types.int;
+              default = 51000;
+              description = "End of UDP port range for WebRTC";
+            };
+
+            use_external_ip = lib.mkOption {
+              type = lib.types.bool;
+              default = false;
+              description = ''
+                When set to true, attempts to discover the host's public IP via STUN.
+                This is useful for cloud environments such as AWS & Google where hosts have an internal IP that maps to an external one.
+              '';
+            };
+          };
+        };
+      };
+      default = { };
+      description = ''
+        LiveKit configuration file expressed in nix.
+
+        For an example configuration, see <https://docs.livekit.io/home/self-hosting/deployment/#configuration>.
+        For all possible values, see <https://github.com/livekit/livekit/blob/master/config-sample.yaml>.
+      '';
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    networking.firewall = lib.mkIf cfg.openFirewall {
+      allowedTCPPorts = [
+        cfg.settings.port
+      ];
+      allowedUDPPortRanges = [
+        {
+          from = cfg.settings.rtc.port_range_start;
+          to = cfg.settings.rtc.port_range_end;
+        }
+      ];
+    };
+
+    systemd.services.livekit = {
+      description = "LiveKit SFU server";
+      documentation = [ "https://docs.livekit.io" ];
+      wantedBy = [ "multi-user.target" ];
+      wants = [ "network-online.target" ];
+      after = [ "network-online.target" ];
+
+      serviceConfig = {
+        LoadCredential = [ "livekit-secrets:${cfg.keyFile}" ];
+        ExecStart = utils.escapeSystemdExecArgs [
+          (lib.getExe cfg.package)
+          "--config=${format.generate "livekit.json" cfg.settings}"
+          "--key-file=/run/credentials/livekit.service/livekit-secrets"
+        ];
+        DynamicUser = true;
+        LockPersonality = true;
+        MemoryDenyWriteExecute = true;
+        ProtectClock = true;
+        ProtectControlGroups = true;
+        ProtectHostname = true;
+        ProtectKernelLogs = true;
+        ProtectKernelModules = true;
+        ProtectKernelTunables = true;
+        PrivateDevices = true;
+        PrivateMounts = true;
+        PrivateUsers = true;
+        RestrictAddressFamilies = [
+          "AF_INET"
+          "AF_INET6"
+          "AF_NETLINK"
+        ];
+        RestrictNamespaces = true;
+        RestrictRealtime = true;
+        ProtectHome = true;
+        SystemCallArchitectures = "native";
+        SystemCallFilter = [
+          "@system-service"
+          "~@privileged"
+          "~@resources"
+        ];
+        Restart = "on-failure";
+        RestartSec = 5;
+        UMask = "077";
+      };
+    };
+  };
+}