2 files changed, 90 insertions, 0 deletions
diff --git a/machines/xnet/net/default.nix b/machines/xnet/net/default.nix
new file mode 100644
index 0000000..2255f53
--- /dev/null
+++ b/machines/xnet/net/default.nix
@@ -0,0 +1,44 @@
+{ config, lib, ... }:
+let
+  cfg = config.xnet.net;
+  inherit (lib) mkOption mkIf types;
+  prefix = "10.26.4";
+in
+{
+  imports = [
+    ./sshd.nix
+  ];
+
+  options.xnet.net = {
+    interface = mkOption {
+      type = types.str;
+      default = "";
+      description = "Network interface connecting to xnet.";
+    };
+
+    addr = mkOption {
+      type = types.ints.between 0 255;
+      description = "Final octet for xnet address.";
+      example = 4;
+    };
+  };
+
+  # TODO:
+  #   - Add assertion that each address is only used once across config
+  #   - Add each host to each other hosts dns configuration
+  config = mkIf (builtins.stringLength cfg.interface > 0) {
+    networking.vlans = {
+      "${cfg.interface}.4" = {
+        inherit (cfg) interface;
+        id = 4;
+      };
+    };
+
+    networking.interfaces = {
+      "${cfg.interface}.4".ipv4.addresses = [{
+        address = "${prefix}.${toString cfg.addr}";
+        prefixLength = 24;
+      }];
+    };
+  };
+}
diff --git a/machines/xnet/net/sshd.nix b/machines/xnet/net/sshd.nix
new file mode 100644
index 0000000..ef225db
--- /dev/null
+++ b/machines/xnet/net/sshd.nix
@@ -0,0 +1,46 @@
+{ config, lib, ... }:
+let
+  cfg = config.xnet.net.sshd;
+  inherit (lib) mkOption mkIf types;
+in
+{
+  options.xnet.net.sshd = {
+    enable = mkOption {
+      type = types.bool;
+      default = false;
+      description = "Enable hardened SSH service.";
+    };
+  };
+
+  config = mkIf cfg.enable {
+    services.openssh = {
+      enable = true;
+      startWhenNeeded = true;
+      openFirewall = true;
+      hostKeys = [{
+        path = "/persist/certs/ssh/ssh_host_ed25519_key";
+        type = "ed25519";
+      }];
+      settings = {
+        UsePAM = true;
+        X11Forwarding = false;
+        PermitRootLogin = "no";
+        PasswordAuthentication = 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}";
+    };
+  };
+}