Fix client crashing with empty text packets

Author: onebeastchris

core/src/main/java/org/geysermc/geyser/network/CodecProcessor.java

@@ -83,7 +83,9 @@
 import org.cloudburstmc.protocol.bedrock.packet.SimpleEventPacket;
 import org.cloudburstmc.protocol.bedrock.packet.SubChunkRequestPacket;
 import org.cloudburstmc.protocol.bedrock.packet.SubClientLoginPacket;
+import org.cloudburstmc.protocol.bedrock.packet.TextPacket;
 import org.cloudburstmc.protocol.common.util.VarInts;
+import org.geysermc.geyser.network.codec.CustomTextPacketSerializer;
 
 /**
  * Processes the Bedrock codec to remove or modify unused or unsafe packets and fields.
@@ -305,6 +307,10 @@ static BedrockCodec processCodec(BedrockCodec codec) {
                     .updateSerializer(PlayerInputPacket.class, ILLEGAL_SERIALIZER);
             }
 
+            if (GameProtocol.is1_21_130orHigher(codec.getProtocolVersion())) {
+                codecBuilder.updateSerializer(TextPacket.class, CustomTextPacketSerializer.INSTANCE);
+            }
+
             if (!Boolean.getBoolean("Geyser.ReceiptPackets")) {
                 codecBuilder.updateSerializer(RefreshEntitlementsPacket.class, IGNORED_SERIALIZER);
                 codecBuilder.updateSerializer(PurchaseReceiptPacket.class, IGNORED_SERIALIZER);

core/src/main/java/org/geysermc/geyser/network/codec/CustomTextPacketSerializer.java

@@ -0,0 +1,115 @@
+/*
+ * Copyright (c) 2025 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.network.codec;
+
+import io.netty.buffer.ByteBuf;
+import org.cloudburstmc.protocol.bedrock.codec.BedrockCodecHelper;
+import org.cloudburstmc.protocol.bedrock.codec.v897.serializer.TextSerializer_v897;
+import org.cloudburstmc.protocol.bedrock.packet.TextPacket;
+import org.cloudburstmc.protocol.common.util.TextConverter;
+
+// Sending empty messages kicks clients with 1.21.130...
+public class CustomTextPacketSerializer extends TextSerializer_v897 {
+
+    public static final CustomTextPacketSerializer INSTANCE = new CustomTextPacketSerializer();
+
+    @Override
+    public void serialize(ByteBuf buffer, BedrockCodecHelper helper, TextPacket packet) {
+        TextPacket.Type type = packet.getType();
+        TextConverter converter = helper.getTextConverter();
+        CharSequence message = packet.getMessage(CharSequence.class);
+        Boolean needsTranslation = converter.needsTranslation(message);
+
+        buffer.writeBoolean(needsTranslation != null ? needsTranslation : packet.isNeedsTranslation());
+        String msg;
+
+        switch (type) {
+            case RAW:
+            case TIP:
+            case SYSTEM:
+                buffer.writeByte(0); // MessageOnly
+                helper.writeString(buffer, "raw");
+                helper.writeString(buffer, "tip");
+                helper.writeString(buffer, "systemMessage");
+                helper.writeString(buffer, "textObjectWhisper");
+                helper.writeString(buffer, "textObjectAnnouncement");
+                helper.writeString(buffer, "textObject");
+                buffer.writeByte(type.ordinal());
+                msg = converter.serialize(message);
+                if (msg.isEmpty()) msg = " ";
+                helper.writeString(buffer, msg);
+                break;
+            case JSON:
+            case WHISPER_JSON:
+            case ANNOUNCEMENT_JSON:
+                buffer.writeByte(0); // MessageOnly
+                helper.writeString(buffer, "raw");
+                helper.writeString(buffer, "tip");
+                helper.writeString(buffer, "systemMessage");
+                helper.writeString(buffer, "textObjectWhisper");
+                helper.writeString(buffer, "textObjectAnnouncement");
+                helper.writeString(buffer, "textObject");
+                buffer.writeByte(type.ordinal());
+                msg = converter.serializeJson(message);
+                if (msg.isEmpty()) msg = " ";
+                helper.writeString(buffer, msg);
+                break;
+            case CHAT:
+            case WHISPER:
+            case ANNOUNCEMENT:
+                buffer.writeByte(1); // AuthorAndMessage
+                helper.writeString(buffer, "chat");
+                helper.writeString(buffer, "whisper");
+                helper.writeString(buffer, "announcement");
+                buffer.writeByte(type.ordinal());
+                helper.writeString(buffer, packet.getSourceName());
+                msg = converter.serialize(message);
+                if (msg.isEmpty()) msg = " ";
+                helper.writeString(buffer, msg);
+                break;
+            case TRANSLATION:
+            case POPUP:
+            case JUKEBOX_POPUP:
+                buffer.writeByte(2); // MessageAndParams
+                helper.writeString(buffer, "translate");
+                helper.writeString(buffer, "popup");
+                helper.writeString(buffer, "jukeboxPopup");
+                buffer.writeByte(type.ordinal());
+                String text = converter.serializeWithArguments(message, packet.getParameters());
+                if (text.isEmpty()) text = " ";
+                helper.writeString(buffer, text);
+                helper.writeArray(buffer, packet.getParameters(), helper::writeString);
+                break;
+            default:
+                throw new UnsupportedOperationException("Unsupported TextType " + type);
+        }
+
+        helper.writeString(buffer, packet.getXuid());
+        helper.writeString(buffer, packet.getPlatformChatId());
+        String filtered = converter.serialize(packet.getFilteredMessage(CharSequence.class));
+        helper.writeOptional(buffer, (s -> !s.isEmpty()), filtered, (buf, codecHelper, s) -> codecHelper.writeString(buf, s));
+    }
+}