feat: initial implementation of patchless packet handling

currently only supports "play packets", thus not including login and handshake

build.gradle

@@ -66,7 +66,7 @@ dependencies {
 }
 
 compileJava { //mappings for lillero-processor
-	options.compilerArgs << '-AmappingsFile=https://data.fantabos.co/output.tsrg'
+	options.compilerArgs << '-AmappingsFile=https://data.fantabos.co/1.16.5.tsrg'
 }
 
 jar {

src/main/java/ftbsc/bscv/Boscovicino.java

@@ -8,6 +8,7 @@ import ftbsc.bscv.api.IModule;
 import ftbsc.bscv.patches.CommandsPatch.CommandsBuiltEvent;
 import ftbsc.bscv.system.Friends;
 import ftbsc.bscv.system.ModManager;
+import ftbsc.bscv.system.PacketHandler;
 import net.minecraft.client.gui.screen.IngameMenuScreen;
 import net.minecraft.client.gui.widget.button.Button;
 import net.minecraft.command.CommandSource;
@@ -27,9 +28,9 @@ import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
 
-@Mod("bscv")
+@Mod(Boscovicino.MOD_ID)
 public class Boscovicino implements ICommons {
-	public static String MOD_ID = "bscv";
+	public static final String MOD_ID = "bscv";
 
 	public static final Logger LOGGER = LogManager.getLogger();
 
@@ -40,7 +41,12 @@ public class Boscovicino implements ICommons {
 	public static ForgeConfigSpec spec;
 
 	private static Friends friends;
-	public static Friends friends() { return Boscovicino.friends; }
+
+	private static PacketHandler packetHandler;
+
+	public static Friends friends() {
+		return Boscovicino.friends;
+	}
 
 	public Boscovicino() {
 		FMLJavaModLoadingContext.get().getModEventBus().addListener(this::onSetupComplete);
@@ -48,13 +54,16 @@ public class Boscovicino implements ICommons {
 		ForgeConfigSpec.Builder cfg = new ForgeConfigSpec.Builder();
 		CommandDispatcher<CommandSource> dp = this.dispatcher;
 
+		// load mods
 		Boscovicino.modManager = new ModManager(cfg, dp);
 		Boscovicino.modManager.load();
-
 		Boscovicino.modManager.finish();
-
 		Boscovicino.spec = cfg.build();
 
+		// initialise packet handler
+		Boscovicino.packetHandler = new PacketHandler();
+
+		// initialise friend manager
 		ForgeConfigSpec.Builder friendSpec = new ForgeConfigSpec.Builder();
 		Boscovicino.friends = new Friends(friendSpec, dp);
 
@@ -62,7 +71,7 @@ public class Boscovicino implements ICommons {
 		ModLoadingContext.get().registerConfig(Type.CLIENT, spec, "bscv.toml");
 		ModLoadingContext.get().registerConfig(Type.CLIENT, friendSpec.build(), "friends.toml");
 
-		// Register ourselves for server and other game events we are interested in
+		// register ourselves on the event bus
 		MinecraftForge.EVENT_BUS.register(this);
 	}
 
@@ -79,7 +88,6 @@ public class Boscovicino implements ICommons {
 
 	private void onSetupComplete(final FMLLoadCompleteEvent event) {
 		LOGGER.info("Initializing modules");
-
 		for (IModule m : modManager.mods) {
 			if (m.isEnabled()) {
 				m.enable(); // re-run enable() to register on the event bus and run enabled callbacks

src/main/java/ftbsc/bscv/modules/hud/InfoDisplay.java

@@ -3,7 +3,7 @@ package ftbsc.bscv.modules.hud;
 import com.google.auto.service.AutoService;
 import ftbsc.bscv.api.ILoadable;
 import ftbsc.bscv.modules.HudModule;
-import ftbsc.bscv.patches.PacketPatch.PacketEvent;
+import ftbsc.bscv.system.PacketHandler.PacketEvent;
 import ftbsc.bscv.tools.Setting;
 import net.minecraft.client.network.play.NetworkPlayerInfo;
 import net.minecraft.network.play.server.SUpdateTimePacket;

src/main/java/ftbsc/bscv/modules/motion/VanillaFlight.java

@@ -1,12 +1,10 @@
 package ftbsc.bscv.modules.motion;
 
 import com.google.auto.service.AutoService;
-import ftbsc.bscv.ICommons;
 import ftbsc.bscv.api.ILoadable;
 import ftbsc.bscv.modules.QuickModule;
-import ftbsc.bscv.patches.PacketPatch.PacketEvent;
+import ftbsc.bscv.system.PacketHandler.PacketEvent;
 import ftbsc.bscv.tools.Setting;
-import net.minecraft.client.entity.player.ClientPlayerEntity;
 import net.minecraft.network.play.client.CPlayerPacket;
 import net.minecraft.util.math.vector.Vector3d;
 import net.minecraftforge.common.ForgeConfigSpec;

src/main/java/ftbsc/bscv/modules/network/PacketLogger.java

@@ -24,7 +24,7 @@ import com.google.gson.JsonPrimitive;
 import ftbsc.bscv.Boscovicino;
 import ftbsc.bscv.api.ILoadable;
 import ftbsc.bscv.modules.QuickModule;
-import ftbsc.bscv.patches.PacketPatch.PacketEvent;
+import ftbsc.bscv.system.PacketHandler.PacketEvent;
 import net.minecraft.network.IPacket;
 import net.minecraft.util.math.vector.Vector2f;
 import net.minecraft.util.math.vector.Vector3d;

src/main/java/ftbsc/bscv/modules/self/AntiHunger.java

@@ -4,7 +4,7 @@ import com.google.auto.service.AutoService;
 import ftbsc.bscv.ICommons;
 import ftbsc.bscv.api.ILoadable;
 import ftbsc.bscv.modules.AbstractModule;
-import ftbsc.bscv.patches.PacketPatch.PacketEvent;
+import ftbsc.bscv.system.PacketHandler.PacketEvent;
 import ftbsc.bscv.tools.Setting;
 import net.minecraft.network.play.client.CEntityActionPacket;
 import net.minecraft.network.play.client.CEntityActionPacket.Action;

src/main/java/ftbsc/bscv/modules/self/AutoDisconnect.java

@@ -4,7 +4,7 @@ import com.google.auto.service.AutoService;
 import ftbsc.bscv.ICommons;
 import ftbsc.bscv.api.ILoadable;
 import ftbsc.bscv.modules.AbstractModule;
-import ftbsc.bscv.patches.PacketPatch.PacketEvent;
+import ftbsc.bscv.system.PacketHandler.PacketEvent;
 import ftbsc.bscv.tools.Setting;
 import net.minecraft.network.play.server.SDisconnectPacket;
 import net.minecraft.network.play.server.SUpdateHealthPacket;

src/main/java/ftbsc/bscv/modules/self/AutoFish.java

@@ -4,7 +4,7 @@ import com.google.auto.service.AutoService;
 import ftbsc.bscv.ICommons;
 import ftbsc.bscv.api.ILoadable;
 import ftbsc.bscv.modules.AbstractModule;
-import ftbsc.bscv.patches.PacketPatch.PacketEvent;
+import ftbsc.bscv.system.PacketHandler.PacketEvent;
 import ftbsc.bscv.tools.Setting;
 import net.minecraft.client.Minecraft;
 import net.minecraft.network.play.server.SPlaySoundEffectPacket;

src/main/java/ftbsc/bscv/modules/self/Freecam.java

@@ -5,7 +5,7 @@ import ftbsc.bscv.Boscovicino;
 import ftbsc.bscv.ICommons;
 import ftbsc.bscv.api.ILoadable;
 import ftbsc.bscv.modules.QuickModule;
-import ftbsc.bscv.patches.PacketPatch.PacketEvent;
+import ftbsc.bscv.system.PacketHandler.PacketEvent;
 import ftbsc.bscv.tools.Keyboard;
 import ftbsc.bscv.tools.Setting;
 import net.minecraft.client.entity.player.RemoteClientPlayerEntity;

src/main/java/ftbsc/bscv/modules/self/Immovable.java

@@ -7,7 +7,7 @@ import ftbsc.bscv.modules.AbstractModule;
 import ftbsc.bscv.patches.BlockPushPatch.PlayerBlockPushEvent;
 import ftbsc.bscv.patches.EntityPushPatch.PlayerEntityPushEvent;
 import ftbsc.bscv.patches.LiquidPushPatch.PlayerLiquidPushEvent;
-import ftbsc.bscv.patches.PacketPatch.PacketEvent;
+import ftbsc.bscv.system.PacketHandler.PacketEvent;
 import ftbsc.bscv.tools.Setting;
 import net.minecraft.network.play.server.SEntityVelocityPacket;
 import net.minecraft.network.play.server.SExplosionPacket;

src/main/java/ftbsc/bscv/modules/vision/UpdateESP.java

@@ -12,7 +12,7 @@ import com.mojang.blaze3d.systems.RenderSystem;
 
 import ftbsc.bscv.api.ILoadable;
 import ftbsc.bscv.modules.QuickModule;
-import ftbsc.bscv.patches.PacketPatch.PacketEvent;
+import ftbsc.bscv.system.PacketHandler.PacketEvent;
 import ftbsc.bscv.tools.Setting;
 import net.minecraft.client.renderer.BufferBuilder;
 import net.minecraft.client.renderer.Tessellator;

src/main/java/ftbsc/bscv/patches/PacketPatch.java

@@ -1,107 +0,0 @@
-package ftbsc.bscv.patches;
-
-import ftbsc.lll.processor.annotations.Find;
-import ftbsc.lll.processor.annotations.Injector;
-import ftbsc.lll.processor.annotations.Patch;
-import ftbsc.lll.processor.annotations.Target;
-import ftbsc.lll.proxies.MethodProxy;
-import ftbsc.lll.tools.InsnSequence;
-import ftbsc.lll.tools.PatternMatcher;
-import ftbsc.lll.tools.debug.BytecodePrinter;
-import ftbsc.lll.tools.nodes.MethodProxyInsnNode;
-import io.netty.channel.ChannelHandlerContext;
-import io.netty.util.concurrent.Future;
-import io.netty.util.concurrent.GenericFutureListener;
-import net.minecraft.network.IPacket;
-import net.minecraft.network.NetworkManager;
-import net.minecraftforge.common.MinecraftForge;
-import net.minecraftforge.eventbus.api.Cancelable;
-import net.minecraftforge.eventbus.api.Event;
-
-import org.objectweb.asm.Opcodes;
-import org.objectweb.asm.tree.*;
-
-public class PacketPatch {
-
-	public static class PacketEvent {
-		@Cancelable
-		public static class Outgoing extends Event {
-			public final IPacket<?> packet;
-
-			public Outgoing(IPacket<?> packet) {
-				this.packet = packet;
-			}
-		}
-
-		@Cancelable
-		public static class Incoming extends Event {
-			public final IPacket<?> packet;
-
-			public Incoming(IPacket<?> packet) {
-				this.packet = packet;
-			}
-		}
-	}
-
-	public static boolean pktIn(IPacket<?> pkt) {
-		return MinecraftForge.EVENT_BUS.post(new PacketEvent.Incoming(pkt));
-	}
-
-	public static boolean pktOut(IPacket<?> pkt) {
-		return MinecraftForge.EVENT_BUS.post(new PacketEvent.Outgoing(pkt));
-	}
-
-	@Patch(value = NetworkManager.class, reason = "add hook to intercept and alter/cancel incoming packets")
-	public abstract static class IncomingPacketInterceptor implements Opcodes {
-		@Find(parent = PacketPatch.class)
-		abstract MethodProxy pktIn();
-
-		@Target
-		public abstract void channelRead0(ChannelHandlerContext ctx, IPacket<?> pak);
-
-		@Injector
-		public void inject(ClassNode clazz, MethodNode main) {
-			AbstractInsnNode found = PatternMatcher.builder()
-				.opcodes(ALOAD, GETFIELD, INVOKEINTERFACE, IFEQ)
-				.ignoreFrames()
-				.ignoreLabels()
-				.ignoreLineNumbers()
-				.build()
-				.find(main)
-				.getLast();
-			
-			LabelNode skip = new LabelNode();
-			InsnSequence is = new InsnSequence();
-			is.add(new VarInsnNode(ALOAD, 2));
-			is.add(new MethodProxyInsnNode(INVOKESTATIC, pktIn()));
-			is.add(new JumpInsnNode(IFEQ, skip));
-			is.add(new InsnNode(RETURN));
-			is.add(skip);
-
-			main.instructions.insert(found, is);
-		}
-	}
-
-	@Patch(value = NetworkManager.class, reason = "add hook to intercept and alter/cancel outgoing packets")
-	public abstract static class OutgoingPacketInterceptor implements Opcodes {
-		@Find(parent = PacketPatch.class)
-		abstract MethodProxy pktOut();
-
-		@Target
-		public abstract void sendPacket(IPacket<?> pak, GenericFutureListener<? extends Future<? super Void>> gfl);
-
-		@Injector
-		public void inject(ClassNode clazz, MethodNode main) {
-			// hook at the top
-			LabelNode skip = new LabelNode();
-			InsnSequence is = new InsnSequence();
-			is.add(new VarInsnNode(ALOAD, 1));
-			is.add(new MethodProxyInsnNode(INVOKESTATIC, pktOut()));
-			is.add(new JumpInsnNode(IFEQ, skip));
-			is.add(new InsnNode(RETURN));
-			is.add(skip);
-
-			main.instructions.insert(is);
-		}
-	}
-}

src/main/java/ftbsc/bscv/system/PacketHandler.java

@@ -0,0 +1,69 @@
+package ftbsc.bscv.system;
+
+import ftbsc.bscv.Boscovicino;
+import io.netty.channel.*;
+import net.minecraft.network.IPacket;
+import net.minecraft.network.NetworkManager;
+import net.minecraftforge.client.event.ClientPlayerNetworkEvent;
+import net.minecraftforge.common.MinecraftForge;
+import net.minecraftforge.eventbus.api.Cancelable;
+import net.minecraftforge.eventbus.api.Event;
+import net.minecraftforge.eventbus.api.SubscribeEvent;
+
+@ChannelHandler.Sharable
+public class PacketHandler extends ChannelDuplexHandler {
+
+	public PacketHandler() {
+		MinecraftForge.EVENT_BUS.register(this);
+	}
+
+	@Override
+	public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
+		if(processPacket(msg, false))
+			super.channelRead(ctx, msg);
+	}
+
+	@Override
+	public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) throws Exception {
+		if(processPacket(msg, true))
+			super.write(ctx, msg, promise);
+	}
+
+	private static boolean processPacket(Object msg, boolean outgoing) {
+		if(msg instanceof IPacket) {
+			IPacket<?> pkt = (IPacket<?>) msg;
+			PacketEvent event = outgoing ? new PacketEvent.Outgoing(pkt) : new PacketEvent.Incoming(pkt);
+			MinecraftForge.EVENT_BUS.post(event);
+			return !event.isCanceled();
+		} else return true;
+	}
+
+	@SubscribeEvent
+	public void registerOnLogin(ClientPlayerNetworkEvent.LoggedInEvent event) {
+		NetworkManager nm = event.getNetworkManager();
+		if(nm != null) {
+			nm.channel().pipeline().addBefore("packet_handler", "bscv_handler", this);
+			Boscovicino.LOGGER.info("Successfully registered PacketHandler!");
+		} else Boscovicino.LOGGER.error("Failed to register PacketHandler: NetworkManager was null!");
+	}
+
+	@Cancelable
+	public static class PacketEvent extends Event {
+
+		public static class Outgoing extends PacketEvent {
+			public final IPacket<?> packet;
+
+			public Outgoing(IPacket<?> packet) {
+				this.packet = packet;
+			}
+		}
+
+		public static class Incoming extends PacketEvent {
+			public final IPacket<?> packet;
+
+			public Incoming(IPacket<?> packet) {
+				this.packet = packet;
+			}
+		}
+	}
+}