1 files changed, 72 insertions, 0 deletions
diff --git a/modules/sshd.nix b/modules/sshd.nix
new file mode 100644
index 0000000..86fea58
--- /dev/null
+++ b/modules/sshd.nix
@@ -0,0 +1,72 @@
+{
+  config,
+  lib,
+  ...
+}:
+
+let
+  cfg = config.depot.net.sshd;
+  inherit (lib)
+    mkOption
+    mkDefault
+    mkIf
+    types
+    ;
+in
+{
+  options.depot.net.sshd = {
+    enable = mkOption {
+      type = types.bool;
+      default = false;
+      description = "Enable hardened SSH service.";
+    };
+    publish = mkOption {
+      type = types.bool;
+      default = false;
+      description = "Publish SSH service over mDNS.";
+    };
+  };
+
+  config = mkIf cfg.enable {
+    services.openssh = {
+      enable = true;
+      startWhenNeeded = true;
+      openFirewall = true;
+      hostKeys = lib.singleton {
+        path = "/persist/certs/ssh/ssh_host_ed25519_key";
+        type = "ed25519";
+      };
+      settings = {
+        UsePAM = false;
+        X11Forwarding = false;
+        PermitRootLogin = "prohibit-password";
+        PasswordAuthentication = mkDefault false;
+        # Ciphers = [ "chacha20-poly1305@openssh.com" ];
+        # Macs = [ "hmac-sha2-512-etm@openssh.com" ];
+        # KexAlgorithms = [ "curve25519-sha256@libssh.org" ];
+      };
+      sftpServerExecutable = "internal-sftp";
+      sftpFlags = [
+        "-f AUTHPRIV"
+        "-l INFO"
+      ];
+      # extraConfig =
+      #   let
+      #     pubkeyTypes = lib.strings.concatStringsSep "," [
+      #       "sk-ssh-ed25519-cert-v01@openssh.com"
+      #       "ssh-ed25519-cert-v01@openssh.com"
+      #       "ssh-ed25519"
+      #     ];
+      #   in
+      #   "PubkeyAcceptedKeyTypes ${pubkeyTypes}";
+    };
+
+    environment.etc."systemd/dnssd/ssh.dnssd".text = mkIf cfg.publish ''
+      [Service]
+      Name=%H
+      Type=_ssh._tcp
+      Port=22
+      TxtText=hello world
+    '';
+  };
+}