From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: William Blake Galbreath <Blake.Galbreath@GMail.com>
Date: Wed, 22 Jan 2020 20:13:40 -0600
Subject: [PATCH] UPnP Port Forwarding


diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
index a859c915117d7660673f580864b3ba2aeb1d9480..4e294958336fd4b86248b42a57398b5de6cad496 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -307,6 +307,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
     // Spigot end
     public static long currentTickLong = 0L; // Paper
     public boolean lagging = false; // Purpur
+    protected boolean upnp = false; // Purpur
 
     public volatile Thread shutdownThread; // Paper
     public volatile boolean abnormalExit = false; // Paper
@@ -970,6 +971,14 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
         // CraftBukkit end
         MinecraftServer.LOGGER.info("Stopping server");
         MinecraftTimings.stopServer(); // Paper
+        // Purpur start
+        if (upnp) {
+            if (dev.omega24.upnp4j.UPnP4J.close(this.getPort(), dev.omega24.upnp4j.util.Protocol.TCP)) {
+                LOGGER.info("[UPnP] Port {} closed", this.getPort());
+            } else {
+                LOGGER.error("[UPnP] Failed to close port {}", this.getPort());
+            }
+        }
         // CraftBukkit start
         if (this.server != null) {
             this.server.disablePlugins();
diff --git a/src/main/java/net/minecraft/server/dedicated/DedicatedServer.java b/src/main/java/net/minecraft/server/dedicated/DedicatedServer.java
index d185dfc8194aad9ed7d1a55817bb4c52834527f2..431414152030810c486839fe6ef645007db20647 100644
--- a/src/main/java/net/minecraft/server/dedicated/DedicatedServer.java
+++ b/src/main/java/net/minecraft/server/dedicated/DedicatedServer.java
@@ -293,6 +293,30 @@ public class DedicatedServer extends MinecraftServer implements ServerInterface
             DedicatedServer.LOGGER.warn("Perhaps a server is already running on that port?");
             return false;
         }
+        // Purpur start
+        if (org.purpurmc.purpur.PurpurConfig.useUPnP) {
+            LOGGER.info("[UPnP] Attempting to start UPnP port forwarding service...");
+            if (dev.omega24.upnp4j.UPnP4J.isUPnPAvailable()) {
+                if (dev.omega24.upnp4j.UPnP4J.isOpen(this.getPort(), dev.omega24.upnp4j.util.Protocol.TCP)) {
+                    this.upnp = false;
+                    LOGGER.info("[UPnP] Port {} is already open", this.getPort());
+                } else if (dev.omega24.upnp4j.UPnP4J.open(this.getPort(), dev.omega24.upnp4j.util.Protocol.TCP)) {
+                    this.upnp = true;
+                    LOGGER.info("[UPnP] Successfully opened port {}", this.getPort());
+                } else {
+                    this.upnp = false;
+                    LOGGER.info("[UPnP] Failed to open port {}", this.getPort());
+                }
+
+                if (upnp) {
+                    LOGGER.info("[UPnP] {}:{}", dev.omega24.upnp4j.UPnP4J.getExternalIP(), this.getPort());
+                }
+            } else {
+                this.upnp = false;
+                LOGGER.error("[UPnP] Service is unavailable");
+            }
+        }
+        // Purpur end
 
         // CraftBukkit start
         // this.setPlayerList(new DedicatedPlayerList(this, this.registryHolder, this.playerDataStorage)); // Spigot - moved up
diff --git a/src/main/java/org/purpurmc/purpur/PurpurConfig.java b/src/main/java/org/purpurmc/purpur/PurpurConfig.java
index 2657f8e49058f7801c2435d499e6133e912021ac..3462a34a7d8e2bbf4c19c02a0b9f19ad5ccdc00f 100644
--- a/src/main/java/org/purpurmc/purpur/PurpurConfig.java
+++ b/src/main/java/org/purpurmc/purpur/PurpurConfig.java
@@ -422,4 +422,9 @@ public class PurpurConfig {
     private static void tpsCatchup() {
         tpsCatchup = getBoolean("settings.tps-catchup", tpsCatchup);
     }
+
+    public static boolean useUPnP = false;
+    private static void networkSettings() {
+        useUPnP = getBoolean("settings.network.upnp-port-forwarding", useUPnP);
+    }
 }