nixos/uptermd: init

nixos/doc/manual/from_md/release-notes/rl-2205.section.xml

@@ -323,6 +323,14 @@
           <link linkend="opt-services.tetrd.enable">services.tetrd</link>.
         </para>
       </listitem>
+      <listitem>
+        <para>
+          <link xlink:href="https://upterm.dev">uptermd</link>, an
+          open-source solution for sharing terminal sessions instantly
+          over the public internet via secure tunnels. Available at
+          <link linkend="opt-services.uptermd.enable">services.uptermd</link>.
+        </para>
+      </listitem>
       <listitem>
         <para>
           <link xlink:href="https://github.com/mbrubeck/agate">agate</link>,

nixos/doc/manual/release-notes/rl-2205.section.md

@@ -99,6 +99,8 @@ In addition to numerous new and upgraded packages, this release has the followin
 
 - [tetrd](https://tetrd.app), share your internet connection from your device to your PC and vice versa through a USB cable. Available at [services.tetrd](#opt-services.tetrd.enable).
 
+- [uptermd](https://upterm.dev), an open-source solution for sharing terminal sessions instantly over the public internet via secure tunnels. Available at [services.uptermd](#opt-services.uptermd.enable).
+
 - [agate](https://github.com/mbrubeck/agate), a very simple server for the Gemini hypertext protocol. Available as [services.agate](options.html#opt-services.agate.enable).
 
 - [ArchiSteamFarm](https://github.com/JustArchiNET/ArchiSteamFarm), a C# application with primary purpose of idling Steam cards from multiple accounts simultaneously. Available as [services.archisteamfarm](options.html#opt-services.archisteamfarm.enable).

nixos/modules/module-list.nix

@@ -936,6 +936,7 @@
   ./services/networking/unifi.nix
   ./services/video/unifi-video.nix
   ./services/video/rtsp-simple-server.nix
+  ./services/networking/uptermd.nix
   ./services/networking/v2ray.nix
   ./services/networking/vsftpd.nix
   ./services/networking/wasabibackend.nix

nixos/modules/services/networking/uptermd.nix

@@ -0,0 +1,106 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+  cfg = config.services.uptermd;
+in
+{
+  options = {
+    services.uptermd = {
+      enable = mkEnableOption "uptermd";
+
+      openFirewall = mkOption {
+        type = types.bool;
+        default = false;
+        description = ''
+          Whether to open the firewall for the port in <option>services.uptermd.port</option>.
+        '';
+      };
+
+      port = mkOption {
+        type = types.port;
+        default = 2222;
+        description = ''
+          Port the server will listen on.
+        '';
+      };
+
+      listenAddress = mkOption {
+        type = types.str;
+        default = "[::]";
+        example = "127.0.0.1";
+        description = ''
+          Address the server will listen on.
+        '';
+      };
+
+      hostKey = mkOption {
+        type = types.nullOr types.path;
+        default = null;
+        example = "/run/keys/upterm_host_ed25519_key";
+        description = ''
+          Path to SSH host key. If not defined, an ed25519 keypair is generated automatically.
+        '';
+      };
+
+      extraFlags = mkOption {
+        type = types.listOf types.str;
+        default = [];
+        example = [ "--debug" ];
+        description = ''
+          Extra flags passed to the uptermd command.
+        '';
+      };
+    };
+  };
+
+  config = mkIf cfg.enable {
+    networking.firewall = mkIf cfg.openFirewall {
+      allowedTCPPorts = [ cfg.port ];
+    };
+
+    systemd.services.uptermd = {
+      description = "Upterm Daemon";
+      wantedBy = [ "multi-user.target" ];
+      after = [ "network.target" ];
+
+      path = [ pkgs.openssh ];
+
+      preStart = mkIf (cfg.hostKey == null) ''
+        if ! [ -f ssh_host_ed25519_key ]; then
+          ssh-keygen \
+            -t ed25519 \
+            -f ssh_host_ed25519_key \
+            -N ""
+        fi
+      '';
+
+      serviceConfig = {
+        StateDirectory = "uptermd";
+        WorkingDirectory = "/var/lib/uptermd";
+        ExecStart = "${pkgs.upterm}/bin/uptermd --ssh-addr ${cfg.listenAddress}:${toString cfg.port} --private-key ${if cfg.hostKey == null then "ssh_host_ed25519_key" else cfg.hostKey} ${concatStringsSep " " cfg.extraFlags}";
+
+        # Hardening
+        AmbientCapabilities = mkIf (cfg.port < 1024) [ "CAP_NET_BIND_SERVICE" ];
+        CapabilityBoundingSet = mkIf (cfg.port < 1024) [ "CAP_NET_BIND_SERVICE" ];
+        PrivateUsers = cfg.port >= 1024;
+        LockPersonality = true;
+        MemoryDenyWriteExecute = true;
+        PrivateDevices = true;
+        ProtectClock = true;
+        ProtectControlGroups = true;
+        ProtectHome = true;
+        ProtectHostname = true;
+        ProtectKernelLogs = true;
+        ProtectKernelModules = true;
+        ProtectKernelTunables = true;
+        RestrictAddressFamilies = [ "AF_INET" "AF_INET6" ];
+        RestrictNamespaces = true;
+        RestrictRealtime = true;
+        SystemCallArchitectures = "native";
+        SystemCallFilter = "@system-service";
+      };
+    };
+  };
+}