Merge branch 'compression' into dev

bootstrap/velocity/src/main/java/org/geysermc/geyser/platform/velocity/GeyserVelocityCompressionDisabler.java

@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) 2019-2021 GeyserMC. http://geysermc.org
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @author GeyserMC
+ * @link https://github.com/GeyserMC/Geyser
+ */
+
+package org.geysermc.geyser.platform.velocity;
+
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelOutboundHandlerAdapter;
+import io.netty.channel.ChannelPromise;
+import org.geysermc.geyser.GeyserImpl;
+
+import java.lang.reflect.Method;
+
+public class GeyserVelocityCompressionDisabler extends ChannelOutboundHandlerAdapter {
+    static final boolean ENABLED;
+    private static final Class<?> COMPRESSION_PACKET_CLASS;
+    private static final Class<?> LOGIN_SUCCESS_PACKET_CLASS;
+    private static final Method SET_COMPRESSION_METHOD;
+
+    static {
+        boolean enabled = false;
+        Class<?> compressionPacketClass = null;
+        Class<?> loginSuccessPacketClass = null;
+        Method setCompressionMethod = null;
+
+        try {
+            compressionPacketClass = Class.forName("com.velocitypowered.proxy.protocol.packet.SetCompression");
+            loginSuccessPacketClass = Class.forName("com.velocitypowered.proxy.protocol.packet.ServerLoginSuccess");
+            setCompressionMethod = Class.forName("com.velocitypowered.proxy.connection.MinecraftConnection")
+                    .getMethod("setCompressionThreshold", int.class);
+            enabled = true;
+        } catch (Exception e) {
+            GeyserImpl.getInstance().getLogger().error("Could not initialize compression disabler!", e);
+        }
+
+        ENABLED = enabled;
+        COMPRESSION_PACKET_CLASS = compressionPacketClass;
+        LOGIN_SUCCESS_PACKET_CLASS = loginSuccessPacketClass;
+        SET_COMPRESSION_METHOD = setCompressionMethod;
+    }
+
+    public GeyserVelocityCompressionDisabler() {
+        if (!ENABLED) {
+            throw new RuntimeException("Geyser compression disabler cannot be initialized in its current state!");
+        }
+    }
+
+    @Override
+    public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) throws Exception {
+        Class<?> msgClass = msg.getClass();
+        if (!COMPRESSION_PACKET_CLASS.isAssignableFrom(msgClass)) {
+            if (LOGIN_SUCCESS_PACKET_CLASS.isAssignableFrom(msgClass)) {
+                // We're past the point that compression can be enabled
+                // Invoke the method as it calls a Netty event and handles removing cleaner than we could
+                Object minecraftConnection = ctx.pipeline().get("handler");
+                SET_COMPRESSION_METHOD.invoke(minecraftConnection, -1);
+
+                ctx.pipeline().remove(this);
+            }
+            super.write(ctx, msg, promise);
+        }
+    }
+}

bootstrap/velocity/src/main/java/org/geysermc/geyser/platform/velocity/GeyserVelocityInjector.java

@@ -34,6 +34,7 @@ import org.geysermc.geyser.network.netty.GeyserInjector;
 import org.geysermc.geyser.network.netty.LocalServerChannelWrapper;
 
 import java.lang.reflect.Field;
+import java.lang.reflect.Method;
 import java.util.function.Supplier;
 
 public class GeyserVelocityInjector extends GeyserInjector {
@@ -67,9 +68,23 @@ public class GeyserVelocityInjector extends GeyserInjector {
         workerGroupField.setAccessible(true);
         EventLoopGroup workerGroup = (EventLoopGroup) workerGroupField.get(connectionManager);
 
+        // This method is what initializes the connection in Java Edition, after Netty is all set.
+        Method initChannel = ChannelInitializer.class.getDeclaredMethod("initChannel", Channel.class);
+        initChannel.setAccessible(true);
+
         ChannelFuture channelFuture = (new ServerBootstrap()
                 .channel(LocalServerChannelWrapper.class)
-                .childHandler(channelInitializer)
+                .childHandler(new ChannelInitializer<>() {
+                    @Override
+                    protected void initChannel(Channel ch) throws Exception {
+                        initChannel.invoke(channelInitializer, ch);
+
+                        if (bootstrap.getGeyserConfig().isDisableCompression() && GeyserVelocityCompressionDisabler.ENABLED) {
+                            ch.pipeline().addAfter("minecraft-encoder", "geyser-compression-disabler",
+                                    new GeyserVelocityCompressionDisabler());
+                        }
+                    }
+                })
                 .group(bossGroup, workerGroup) // Cannot be DefaultEventLoopGroup
                 .childOption(ChannelOption.WRITE_BUFFER_WATER_MARK, serverWriteMark) // Required or else rare network freezes can occur
                 .localAddress(LocalAddress.ANY))