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 fa6bf262da81837c7ff7b115a0a7b4a7f266037a..843d86bbb615d6257c143a3822a2af214af1a737 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -321,6 +321,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
     public static long currentTickLong = 0L; // Paper - track current tick as a long
     public boolean isIteratingOverLevels = false; // Paper - Throw exception on world create while being ticked
     public boolean lagging = false; // Purpur
+    protected boolean upnp = false; // Purpur
 
     public static <S extends MinecraftServer> S spin(Function<Thread, S> serverFactory) {
         AtomicReference<S> atomicreference = new AtomicReference();
@@ -954,6 +955,14 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
         MinecraftServer.LOGGER.info("Stopping server");
         Commands.COMMAND_SENDING_POOL.shutdownNow(); // Paper - Perf: Async command map building; Shutdown and don't bother finishing
         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 70b0d8f18df7380d54a9c28e0d9060964e338993..1331b58b60142513708c8188f04c6818d75d6160 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
             if (true) throw new IllegalStateException("Failed to bind to port", ioexception); // Paper - Propagate failed to bind to port error
             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.registries(), 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 95fd67671ad690052f7d697ef11e327969af5ef8..d1e825e11727a6923ffd9a524dadde3ed9436821 100644
--- a/src/main/java/org/purpurmc/purpur/PurpurConfig.java
+++ b/src/main/java/org/purpurmc/purpur/PurpurConfig.java
@@ -410,4 +410,9 @@ 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);
+    }
 }