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 7e7f66ab202e5ac3bd8f91ed0ab1db51c2679101..027bc1f3ad7c6cab51b57122eae553b010082f1c 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -320,6 +320,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
     public final io.papermc.paper.configuration.PaperConfigurations paperConfigurations; // Paper - add paper configuration files
     public boolean isIteratingOverLevels = false; // Paper - Throw exception on world create while being ticked
     public boolean lagging = false; // Purpur
+    protected boolean upnp = false; // Purpur
 
     public volatile Thread shutdownThread; // Paper
     public volatile boolean abnormalExit = false; // Paper
@@ -1043,6 +1044,15 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
         Commands.COMMAND_SENDING_POOL.shutdownNow(); // Paper - Perf: Async command map building; Shutdown and don't bother finishing
         MinecraftTimings.stopServer(); // Paper
         this.server.spark.disable(); // Paper - spark
+        // 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());
+            }
+        }
+        // Purpur end
         // 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 e093ef5b2712776767db6b9b78e46bbee5b91ee5..7288850095495472ef35c8eb03fb519dd0f704ee 100644
--- a/src/main/java/net/minecraft/server/dedicated/DedicatedServer.java
+++ b/src/main/java/net/minecraft/server/dedicated/DedicatedServer.java
@@ -297,6 +297,30 @@ 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 f4c8dd204943f77760f0a7f73838776bf2f85b63..3351f1aad470e27501dd60436756fada434b9e25 100644
--- a/src/main/java/org/purpurmc/purpur/PurpurConfig.java
+++ b/src/main/java/org/purpurmc/purpur/PurpurConfig.java
@@ -421,4 +421,9 @@ 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);
+    }
 }