Fix #245: Resolve unexpected teleport confirmation ID kick on 1.9+ servers

viaforge-mc189/src/main/java/com/viaversion/viaforge/mixin/impl/MixinNetHandlerPlayClient.java

@@ -18,12 +18,19 @@
 
 package com.viaversion.viaforge.mixin.impl;
 
+import com.viaversion.viaforge.mixin.interfaces.IS08;
+import com.viaversion.viarewind.protocol.v1_9to1_8.Protocol1_9To1_8;
 import com.viaversion.viaversion.api.connection.UserConnection;
+import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
+import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
+import com.viaversion.viaversion.api.type.Types;
 import com.viaversion.viaversion.connection.ConnectionDetails;
 import com.viaversion.viaforge.common.ViaForgeCommon;
+import com.viaversion.viaversion.protocols.v1_8to1_9.packet.ServerboundPackets1_9;
 import io.netty.channel.Channel;
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.network.NetHandlerPlayClient;
+import net.minecraft.network.play.server.S08PacketPlayerPosLook;
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Inject;
@@ -43,4 +50,18 @@ public void sendConnectionDetails(CallbackInfo ci) {
         ConnectionDetails.sendConnectionDetails(connection, ConnectionDetails.MOD_CHANNEL);
     }
 
+    @Inject(method = "handlePlayerPosLook", at = @At(value = "INVOKE", target = "Lnet/minecraft/entity/player/EntityPlayer;setPositionAndRotation(DDDFF)V", shift = At.Shift.AFTER))
+    public void handleTeleportPacket(S08PacketPlayerPosLook packetIn, CallbackInfo ci) {
+        final Channel channel = Minecraft.getMinecraft().thePlayer.sendQueue.getNetworkManager().channel();
+        final UserConnection connection = channel.attr(ViaForgeCommon.VF_VIA_USER).get();
+        if (connection == null) {
+            return;
+        }
+
+        if (ViaForgeCommon.getManager().getTargetVersion().newerThanOrEqualTo(ProtocolVersion.v1_9)) {
+            PacketWrapper packet = PacketWrapper.create(ServerboundPackets1_9.ACCEPT_TELEPORTATION, connection);
+            packet.write(Types.VAR_INT, ((IS08)packetIn).getTeleportId());
+            packet.sendToServer(Protocol1_9To1_8.class);
+        }
+    }
 }

viaforge-mc189/src/main/java/com/viaversion/viaforge/mixin/impl/MixinS08PacketPlayerPosLook.java

@@ -0,0 +1,61 @@
+/*
+ * This file is part of ViaForge - https://github.com/ViaVersion/ViaForge
+ * Copyright (C) 2021-2026 Florian Reuth <git@florianreuth.de> and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.viaversion.viaforge.mixin.impl;
+
+import com.viaversion.viaforge.common.ViaForgeCommon;
+import com.viaversion.viaforge.mixin.interfaces.IS08;
+import com.viaversion.viarewind.protocol.v1_9to1_8.storage.PlayerPositionTracker;
+import com.viaversion.viaversion.api.connection.UserConnection;
+import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
+import io.netty.channel.Channel;
+import net.minecraft.client.Minecraft;
+import net.minecraft.network.PacketBuffer;
+import net.minecraft.network.play.server.S08PacketPlayerPosLook;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Unique;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+import java.io.IOException;
+
+@Mixin(S08PacketPlayerPosLook.class)
+public class MixinS08PacketPlayerPosLook implements IS08 {
+
+    @Unique
+    private int teleportId;
+
+    @Inject(method = "readPacketData", at = @At("RETURN"))
+    public void onReadPacketData(PacketBuffer buf, CallbackInfo ci) throws IOException {
+        if (ViaForgeCommon.getManager().getTargetVersion().newerThanOrEqualTo(ProtocolVersion.v1_9)) {
+            Channel channel = Minecraft.getMinecraft().thePlayer.sendQueue.getNetworkManager().channel();
+            UserConnection connection = channel.attr(ViaForgeCommon.VF_VIA_USER).get();
+            if (connection != null) {
+                PlayerPositionTracker tracker = connection.get(PlayerPositionTracker.class);
+                if (tracker != null) {
+                    this.teleportId = tracker.getConfirmId();
+                }
+            }
+        }
+    }
+
+    @Override
+    public int getTeleportId() {
+        return this.teleportId;
+    }
+}

viaforge-mc189/src/main/java/com/viaversion/viaforge/mixin/interfaces/IS08.java

@@ -0,0 +1,23 @@
+/*
+ * This file is part of ViaForge - https://github.com/ViaVersion/ViaForge
+ * Copyright (C) 2021-2026 Florian Reuth <git@florianreuth.de> and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.viaversion.viaforge.mixin.interfaces;
+
+public interface IS08 {
+    int getTeleportId();
+}

viaforge-mc189/src/main/resources/mixins.viaforge.json

@@ -11,6 +11,7 @@
     "MixinGuiScreenAddServer",
     "MixinGuiScreenServerList",
     "MixinNetHandlerPlayClient",
+    "MixinS08PacketPlayerPosLook",
     "MixinServerData",
     "compatibility.patcher.MixinProtocolVersionDetector",
     "connect.MixinGuiConnecting_1",