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/net/minecraft/server/MinecraftServer.java b/net/minecraft/server/MinecraftServer.java
index 9219b31a7273b08e7acd1a953c260a5520333922..80a8bd2dc32763f8ee2062c2d1b36188f2532523 100644
--- a/net/minecraft/server/MinecraftServer.java
+++ b/net/minecraft/server/MinecraftServer.java
@@ -331,6 +331,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
     public boolean isIteratingOverLevels = false; // Paper - Throw exception on world create while being ticked
     private final Set<String> pluginsBlockingSleep = new java.util.HashSet<>(); // Paper - API to allow/disallow tick sleeping
     public boolean lagging = false; // Purpur - Lagging threshold
+    protected boolean upnp = false; // Purpur - UPnP Port Forwarding
 
     public volatile Thread shutdownThread; // Paper
     public volatile boolean abnormalExit = false; // Paper
@@ -1057,6 +1058,15 @@ 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
+        // Purpur start - UPnP Port Forwarding
+        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());
+            }
+        }
+        // Purpur end - UPnP Port Forwarding
         // CraftBukkit start
         if (this.server != null) {
             this.server.spark.disable(); // Paper - spark
diff --git a/net/minecraft/server/dedicated/DedicatedServer.java b/net/minecraft/server/dedicated/DedicatedServer.java
index 6252001c03230f35c5ec7354faa3720e407dee6c..683c7c373e1b9f764bb9b53cdaace9740f607c75 100644
--- a/net/minecraft/server/dedicated/DedicatedServer.java
+++ b/net/minecraft/server/dedicated/DedicatedServer.java
@@ -301,6 +301,30 @@ 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 - UPnP Port Forwarding
+        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 - UPnP Port Forwarding
 
         // 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 82903b6ce4cf30b2d95001455ee4e3a454b3ddd5..f84248af574887e48180e88b3e365f7008dd1c16 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);
+    }
 }