config: Add support for custom client port configuration

This commit introduces the ability to specify a custom port for the client
configuration. This feature is particularly useful when the WireGuard server
is behind a port forwarding setup, allowing clients to connect using the
correct port number.

With this change, users can now define the desired client port in the
configuration file, ensuring seamless connectivity even in scenarios where
the client's listening port differs from the standard WireGuard port.

docker-compose.yml

@@ -15,6 +15,7 @@ services:
       # - PASSWORD=foobar123
       # - PORT=51821
       # - WG_PORT=51820
+      # - WG_CONFIG_PORT=92820
       # - WG_DEFAULT_ADDRESS=10.8.0.x
       # - WG_DEFAULT_DNS=1.1.1.1
       # - WG_MTU=1420

src/config.js

@@ -10,6 +10,7 @@ module.exports.WG_PATH = process.env.WG_PATH || '/etc/wireguard/';
 module.exports.WG_DEVICE = process.env.WG_DEVICE || 'eth0';
 module.exports.WG_HOST = process.env.WG_HOST;
 module.exports.WG_PORT = process.env.WG_PORT || '51820';
+module.exports.WG_CONFIG_PORT = process.env.WG_CONFIG_PORT || process.env.WG_PORT || '51820';
 module.exports.WG_MTU = process.env.WG_MTU || null;
 module.exports.WG_PERSISTENT_KEEPALIVE = process.env.WG_PERSISTENT_KEEPALIVE || '0';
 module.exports.WG_DEFAULT_ADDRESS = process.env.WG_DEFAULT_ADDRESS || '10.8.0.x';

src/lib/WireGuard.js

@@ -13,6 +13,7 @@ const {
   WG_PATH,
   WG_HOST,
   WG_PORT,
+  WG_CONFIG_PORT,
   WG_MTU,
   WG_DEFAULT_DNS,
   WG_DEFAULT_ADDRESS,
@@ -207,7 +208,7 @@ PublicKey = ${config.server.publicKey}
 ${client.preSharedKey ? `PresharedKey = ${client.preSharedKey}\n` : ''
 }AllowedIPs = ${WG_ALLOWED_IPS}
 PersistentKeepalive = ${WG_PERSISTENT_KEEPALIVE}
-Endpoint = ${WG_HOST}:${WG_PORT}`;
+Endpoint = ${WG_HOST}:${WG_CONFIG_PORT}`;
   }
 
   async getClientQRCodeSVG({ clientId }) {