add ssh module

modules/ssh/default.nix

@@ -0,0 +1,50 @@
+## Secure Shell
+## ============
+##
+## Provide SSH service using Dropbear
+
+{ lib, pkgs, config, ...}:
+let
+  inherit (lib) mkOption types;
+  inherit (pkgs) liminix;
+  mkBoolOption = description : mkOption {
+    type = types.bool;
+    inherit description;
+    default = true;
+  };
+
+in {
+  options = {
+    system.service.ssh = mkOption {
+      type = liminix.lib.types.serviceDefn;
+    };
+  };
+  config.system.service = {
+    ssh = liminix.callService ./ssh.nix {
+      address = mkOption {
+        type = types.nullOr types.str;
+        default = null;
+        description = "Listen on specified address";
+        example = "127.0.0.1";
+      };
+      port = mkOption {
+        type = types.port;
+        default = 22;
+        description = "Listen on specified TCP port";
+      };
+      allowRoot = mkBoolOption "Allow root to login";
+      allowPasswordLogin = mkBoolOption "Allow login using password (disable for public key auth only)";
+      allowPasswordLoginForRoot = mkBoolOption "Allow root to login using password (disable for public key auth only)";
+      allowLocalPortForward = mkBoolOption "Enable local port forwarding";
+      allowRemotePortForward = mkBoolOption "Enable remote port forwarding";
+      allowRemoteConnectionToForwardedPorts = mkOption {
+        type = types.bool; default = false;
+        description = "Allow remote hosts to connect to local forwarded ports (by default they are bound to loopback)";
+      };
+      extraConfig = mkOption {
+        type = types.separatedString " ";
+        default = "";
+      };
+    };
+  };
+}