4 files changed, 107 insertions, 1 deletions
diff --git a/modules/services/nixos/default.nix b/modules/services/nixos/default.nix
index 9c95180..db637e8 100644
--- a/modules/services/nixos/default.nix
+++ b/modules/services/nixos/default.nix
@@ -4,6 +4,7 @@
     ./audio.nix
     ./bluetooth.nix
     ./tailscale.nix
+    ./wireguard
     ./selfhost
     ./ssh.nix
   ];
diff --git a/modules/services/nixos/wireguard/client.nix b/modules/services/nixos/wireguard/client.nix
new file mode 100644
index 0000000..ec41ad5
--- /dev/null
+++ b/modules/services/nixos/wireguard/client.nix
@@ -0,0 +1,50 @@
+{
+  config,
+  lib,
+  ...
+}: let
+  cfg = config.collinux.services.networking.wireguard;
+in
+  lib.mkIf (cfg.enable && cfg.localPeer.role == "spoke") {
+    boot.extraModulePackages = [config.boot.kernelPackages.wireguard];
+
+    # we know the machine is configured to use networkd already
+    systemd.network = {
+      netdevs = {
+        "10-wg0" = {
+          netdevConfig = {
+            Kind = "wireguard";
+            Name = "wg0";
+          };
+
+          wireguardConfig = {
+            PrivateKeyFile = cfg.privateKeyFile;
+            ListenPort = 51820;
+          };
+
+          wireguardPeers = [
+            {
+              PublicKey = ""; # will configure later
+              AllowedIPs = ["100.100.0.1"];
+              Endpoint = "williamsfam.us.com:51820"; # not configured yet
+            }
+          ];
+        };
+      };
+
+      networks."12-wireguard" = {
+        name = "wg0";
+
+        networkConfig = {
+          Address = cfg.ip;
+          Gateway = "100.100.0.1";
+          DHCP = "no";
+
+          # disable ipv6 addresses
+          IPv6AcceptRA = "no";
+          IPv6PrivacyExtensions = "no";
+          LinkLocalAddressing = "no";
+        };
+      };
+    };
+  }
diff --git a/modules/services/nixos/wireguard/default.nix b/modules/services/nixos/wireguard/default.nix
new file mode 100644
index 0000000..f7ecff0
--- /dev/null
+++ b/modules/services/nixos/wireguard/default.nix
@@ -0,0 +1,6 @@
+{
+  imports = [
+    ./client.nix
+    ./server.nix
+  ];
+}
diff --git a/modules/services/options.nix b/modules/services/options.nix
index f42dd12..cae9e72 100644
--- a/modules/services/options.nix
+++ b/modules/services/options.nix
@@ -32,12 +32,49 @@ in {
           };
         };
         tailscale.enable = mkEnableOption "tailscale";
+        wireguard = let
+          spokeOpts = {
+            ip = mkOption {
+              type = ip_addr;
+            };
+            key = mkOption {
+              type = lib.types.str;
+            };
+          };
+
+          hubOpts =
+            spokeOpts
+            // {
+              domain = mkOption {
+                type = lib.types.str;
+              };
+              port = mkOption {
+                type = lib.types.port;
+              };
+            };
+        in {
+          # based on https://www.procustodibus.com/blog/2020/11/wireguard-hub-and-spoke-config
+          enable = mkEnableOption "wireguard";
+
+          peersConfig = {
+            hub = mkOption {
+              type = lib.types.attrsOf (lib.types.submodule {options = hubOpts;});
+            };
+
+            spokes = mkOption {
+              type = lib.types.attrsOf (lib.types.submodule {options = spokeOpts;});
+            };
+          };
+
+          localPeer = mkOption {
+            type = lib.types.oneOf [hubOpts spokeOpts];
+          };
+        };
         sshd.enable = mkEnableOption "OpenSSH server";
       };
       audio = {
         enable = mkEnableOption "pipewire + wireplumber";
         pulse.enable = mkEnableOption "pipewire-pulse";
-        # some config to make audio work with wine (TODO for jupiter)
       };
       bluetooth = {
         enable = mkEnableOption "bluetooth";
@@ -97,6 +134,18 @@ in {
         assertion = with config.collinux.services.networking; (iwd.enable && !networkmanager.enable && !networkd.enable) || (!iwd.enable && networkmanager.enable && !networkd.enable) || (!iwd.enable && !networkmanager.enable && networkd.enable);
         message = "only one networking method (iwd, networkmanager, static) can be active";
       }
+      {
+        assertion = with config.collinux.services.networking; !(wireguard.enable && tailscale.enable);
+        message = "only one vpn method (tailscale, wireguard) can be active";
+      }
+      {
+        assertion = with config.collinux.services.networking; wireguard.enable && !networkd.enable;
+        message = "wireguard configuration only supports networkd at the moment";
+      }
+      {
+        assertion = with config.collinux.services.networking.wireguard; enable && (peersConfig |> (builtins.filter (m: m.role == "hub")) |> lib.count) == 1;
+        message = "there must be exactly one hub in the wireguard configuration";
+      }
     ];
   };
 }