PaperMC/patches/server/0186-Call-PaperServerListPingEvent-for-legacy-pings.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Minecrell <minecrell@minecrell.net>
Date: Wed, 11 Oct 2017 19:30:51 +0200
Subject: [PATCH] Call PaperServerListPingEvent for legacy pings


diff --git a/src/main/java/com/destroystokyo/paper/network/PaperLegacyStatusClient.java b/src/main/java/com/destroystokyo/paper/network/PaperLegacyStatusClient.java
new file mode 100644
index 0000000000000000000000000000000000000000..cc54b1c207981235b5160e8773b27cf9a5dcd4d5
--- /dev/null
+++ b/src/main/java/com/destroystokyo/paper/network/PaperLegacyStatusClient.java
@@ -0,0 +1,75 @@
+package com.destroystokyo.paper.network;
+
+import com.destroystokyo.paper.event.server.PaperServerListPingEvent;
+import net.kyori.adventure.text.serializer.plain.PlainTextComponentSerializer;
+import net.minecraft.ChatFormatting;
+import net.minecraft.server.MinecraftServer;
+import org.apache.commons.lang3.StringUtils;
+
+import java.net.InetSocketAddress;
+
+import javax.annotation.Nullable;
+
+public final class PaperLegacyStatusClient implements StatusClient {
+
+    private final InetSocketAddress address;
+    private final int protocolVersion;
+    @Nullable private final InetSocketAddress virtualHost;
+
+    private PaperLegacyStatusClient(InetSocketAddress address, int protocolVersion, @Nullable InetSocketAddress virtualHost) {
+        this.address = address;
+        this.protocolVersion = protocolVersion;
+        this.virtualHost = virtualHost;
+    }
+
+    @Override
+    public InetSocketAddress getAddress() {
+        return this.address;
+    }
+
+    @Override
+    public int getProtocolVersion() {
+        return this.protocolVersion;
+    }
+
+    @Nullable
+    @Override
+    public InetSocketAddress getVirtualHost() {
+        return this.virtualHost;
+    }
+
+    @Override
+    public boolean isLegacy() {
+        return true;
+    }
+
+    public static PaperServerListPingEvent processRequest(MinecraftServer server,
+            InetSocketAddress address, int protocolVersion, @Nullable InetSocketAddress virtualHost) {
+
+        PaperServerListPingEvent event =  new PaperServerListPingEventImpl(server,
+                new PaperLegacyStatusClient(address, protocolVersion, virtualHost), Byte.MAX_VALUE, null);
+        server.server.getPluginManager().callEvent(event);
+
+        if (event.isCancelled()) {
+            return null;
+        }
+
+        return event;
+    }
+
+    @SuppressWarnings("deprecation") // Valid as this is the legacy status client
+    public static String getMotd(PaperServerListPingEvent event) {
+        return getFirstLine(event.getMotd());
+    }
+
+    public static String getUnformattedMotd(PaperServerListPingEvent event) {
+        // Strip color codes and all other occurrences of the color char (because it's used as delimiter)
+        return getFirstLine(StringUtils.remove(PlainTextComponentSerializer.plainText().serialize(event.motd()), ChatFormatting.PREFIX_CODE));
+    }
+
+    private static String getFirstLine(String s) {
+        int pos = s.indexOf('\n');
+        return pos >= 0 ? s.substring(0, pos) : s;
+    }
+
+}
diff --git a/src/main/java/net/minecraft/server/network/LegacyQueryHandler.java b/src/main/java/net/minecraft/server/network/LegacyQueryHandler.java
index 738da83f82bf01bde94c956ac22525a638db3906..d4f5a98a0b1ca9f2a8baa6e0b27353df94d1f333 100644
--- a/src/main/java/net/minecraft/server/network/LegacyQueryHandler.java
+++ b/src/main/java/net/minecraft/server/network/LegacyQueryHandler.java
@@ -46,11 +46,22 @@ public class LegacyQueryHandler extends ChannelInboundHandlerAdapter {
                 SocketAddress socketaddress = channelhandlercontext.channel().remoteAddress();
                 int i = bytebuf.readableBytes();
                 String s = null; // Paper
-                org.bukkit.event.server.ServerListPingEvent event = org.bukkit.craftbukkit.event.CraftEventFactory.callServerListPingEvent(socketaddress, this.server.getMotd(), this.server.getPlayerCount(), this.server.getMaxPlayers()); // CraftBukkit
+                // org.bukkit.event.server.ServerListPingEvent event = org.bukkit.craftbukkit.event.CraftEventFactory.callServerListPingEvent(socketaddress, this.server.getMotd(), this.server.getPlayerCount(), this.server.getMaxPlayers()); // CraftBukkit // Paper
+                com.destroystokyo.paper.event.server.PaperServerListPingEvent event; // Paper
 
                 if (i == 0) {
                     LegacyQueryHandler.LOGGER.debug("Ping: (<1.3.x) from {}", socketaddress);
-                    s = LegacyQueryHandler.createVersion0Response(this.server, event); // CraftBukkit
+
+                    // Paper start - Call PaperServerListPingEvent and use results
+                    event = com.destroystokyo.paper.network.PaperLegacyStatusClient.processRequest(net.minecraft.server.MinecraftServer.getServer(), (java.net.InetSocketAddress) socketaddress, 39, null);
+                    if (event == null) {
+                        channelhandlercontext.close();
+                        bytebuf.release();
+                        flag = false;
+                        return;
+                    }
+                    s = String.format(Locale.ROOT, "%s\u00a7%d\u00a7%d", com.destroystokyo.paper.network.PaperLegacyStatusClient.getUnformattedMotd(event), event.getNumPlayers(), event.getMaxPlayers());
+                    // Paper end
                     LegacyQueryHandler.sendFlushAndClose(channelhandlercontext, LegacyQueryHandler.createLegacyDisconnectPacket(channelhandlercontext.alloc(), s));
                 } else {
                     if (bytebuf.readUnsignedByte() != 1) {
@@ -75,7 +86,18 @@ public class LegacyQueryHandler extends ChannelInboundHandlerAdapter {
                         LegacyQueryHandler.LOGGER.debug("Ping: (1.4-1.5.x) from {}", socketaddress);
                     }
 
-                    if (s == null) s = LegacyQueryHandler.createVersion1Response(this.server, event); // CraftBukkit // Paper
+                    if (s == null) {
+                        // Paper start - Call PaperServerListPingEvent and use results
+                        event = com.destroystokyo.paper.network.PaperLegacyStatusClient.processRequest(net.minecraft.server.MinecraftServer.getServer(), (java.net.InetSocketAddress) socketaddress, 127, null); // Paper
+                        if (event == null) {
+                            channelhandlercontext.close();
+                            bytebuf.release();
+                            flag = false;
+                            return;
+                        }
+                        s = String.format(Locale.ROOT, "\u00a71\u0000%d\u0000%s\u0000%s\u0000%d\u0000%d", new Object[] { event.getProtocolVersion(), this.server.getServerVersion(), event.getMotd(), event.getNumPlayers(), event.getMaxPlayers()}); // CraftBukkit
+                        // Paper end
+                    }
                     LegacyQueryHandler.sendFlushAndClose(channelhandlercontext, LegacyQueryHandler.createLegacyDisconnectPacket(channelhandlercontext.alloc(), s));
                 }
 
@@ -187,8 +209,16 @@ public class LegacyQueryHandler extends ChannelInboundHandlerAdapter {
 
         LOGGER.debug("Ping: (1.6) from {}", ctx.channel().remoteAddress());
 
-        String response = String.format("\u00a71\u0000%d\u0000%s\u0000%s\u0000%d\u0000%d",
-            Byte.MAX_VALUE, server.getServerVersion(), server.getMotd(), server.getPlayerCount(), server.getMaxPlayers());
+        java.net.InetSocketAddress virtualHost = com.destroystokyo.paper.network.PaperNetworkClient.prepareVirtualHost(host, port);
+        com.destroystokyo.paper.event.server.PaperServerListPingEvent event = com.destroystokyo.paper.network.PaperLegacyStatusClient.processRequest(
+                server, (java.net.InetSocketAddress) ctx.channel().remoteAddress(), protocolVersion, virtualHost);
+        if (event == null) {
+            ctx.close();
+            return null;
+        }
+
+        String response = String.format("\u00a71\u0000%d\u0000%s\u0000%s\u0000%d\u0000%d", event.getProtocolVersion(), event.getVersion(),
+            com.destroystokyo.paper.network.PaperLegacyStatusClient.getMotd(event), event.getNumPlayers(), event.getMaxPlayers());
         return response;
     }