Add support for encoding custom crafted packets with UnknownPacket

bedrock/bedrock-common/src/main/java/com/nukkitx/protocol/bedrock/BedrockPacketCodec.java

@@ -11,6 +11,7 @@
 import gnu.trove.map.hash.TIntObjectHashMap;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.PooledByteBufAllocator;
+import io.netty.util.ReferenceCountUtil;
 import io.netty.util.internal.logging.InternalLogger;
 import io.netty.util.internal.logging.InternalLoggerFactory;
 import lombok.AccessLevel;
@@ -32,7 +33,7 @@ public final class BedrockPacketCodec {
     @Getter
     private final String minecraftVersion;
     private final PacketSerializer<BedrockPacket>[] serializers;
-    private final TIntHashBiMap<Class<BedrockPacket>> idBiMap;
+    private final TIntHashBiMap<Class<? extends BedrockPacket>> idBiMap;
     private final PacketSerializer<PacketHeader> headerSerializer;
 
     public static Builder builder() {
@@ -64,28 +65,35 @@ public BedrockPacket tryDecode(ByteBuf buf) throws PacketSerializeException {
         return packet;
     }
 
+    @SuppressWarnings("unchecked")
     public ByteBuf tryEncode(BedrockPacket packet) throws PacketSerializeException {
-        PacketHeader header = packet.getHeader();
-        if (header == null) {
-            header = new PacketHeader();
-        }
-        int packetId = getId(packet);
-        header.setPacketId(packetId);
-
         ByteBuf buf = PooledByteBufAllocator.DEFAULT.directBuffer();
         try {
+            PacketHeader header = packet.getHeader();
+            if (header == null) {
+                header = new PacketHeader();
+            }
+
+            PacketSerializer<BedrockPacket> serializer;
+            if (packet instanceof UnknownPacket) {
+                serializer = (PacketSerializer<BedrockPacket>) packet;
+            } else {
+                int packetId = getId(packet.getClass());
+                header.setPacketId(packetId);
+                serializer = serializers[packetId];
+            }
             headerSerializer.serialize(buf, header);
-            serializers[packetId].serialize(buf, packet);
+            serializer.serialize(buf, packet);
         } catch (Exception e) {
             buf.release();
             throw new PacketSerializeException("Error whilst serializing " + packet.getClass().getSimpleName(), e);
+        } finally {
+            ReferenceCountUtil.release(packet);
         }
         return buf;
     }
 
-    @SuppressWarnings("unchecked")
-    public int getId(BedrockPacket packet) {
-        Class<BedrockPacket> clazz = (Class<BedrockPacket>) packet.getClass();
+    public int getId(Class<? extends BedrockPacket> clazz) {
         int id = idBiMap.get(clazz);
         if (id == -1) {
             throw new IllegalArgumentException("Packet ID for " + clazz.getName() + " does not exist.");
@@ -97,7 +105,7 @@ public int getId(BedrockPacket packet) {
     @NoArgsConstructor(access = AccessLevel.PRIVATE)
     public static class Builder {
         private final TIntObjectMap<PacketSerializer<BedrockPacket>> serializers = new TIntObjectHashMap<>();
-        private final TIntHashBiMap<Class<BedrockPacket>> idBiMap = new TIntHashBiMap<>((Class) UnknownPacket.class);
+        private final TIntHashBiMap<Class<? extends BedrockPacket>> idBiMap = new TIntHashBiMap<>((Class) UnknownPacket.class);
         private int protocolVersion = -1;
         private String minecraftVersion = null;
         private PacketSerializer<PacketHeader> headerSerializer = null;

bedrock/bedrock-common/src/main/java/com/nukkitx/protocol/bedrock/BedrockSession.java

@@ -97,7 +97,7 @@ private void checkPacket(BedrockPacket packet) {
         Preconditions.checkState(this.packetCodec != BedrockCompat.COMPAT_CODEC, "No PacketCodec is set!");
 
         // Verify that the packet ID exists.
-        this.packetCodec.getId(packet);
+        this.packetCodec.getId(packet.getClass());
     }
 
     public void sendWrapped(Collection<BedrockPacket> packets, boolean encrypt) {

bedrock/bedrock-common/src/main/java/com/nukkitx/protocol/bedrock/packet/UnknownPacket.java

@@ -5,12 +5,13 @@
 import com.nukkitx.protocol.serializer.PacketSerializer;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.ByteBufUtil;
+import io.netty.util.ReferenceCounted;
 import lombok.Data;
 import lombok.EqualsAndHashCode;
 
 @Data
 @EqualsAndHashCode(callSuper = true)
-public final class UnknownPacket extends BedrockPacket implements PacketSerializer<UnknownPacket> {
+public final class UnknownPacket extends BedrockPacket implements PacketSerializer<UnknownPacket>, ReferenceCounted {
     private ByteBuf payload;
 
     @Override
@@ -32,4 +33,54 @@ public String toString() {
     public final boolean handle(BedrockPacketHandler handler) {
         return false;
     }
+
+    @Override
+    public int refCnt() {
+        if (this.payload == null) {
+            return 0;
+        }
+        return payload.refCnt();
+    }
+
+    @Override
+    public UnknownPacket retain() {
+        if (this.payload != null) {
+            this.payload.retain();
+        }
+        return this;
+    }
+
+    @Override
+    public UnknownPacket retain(int increment) {
+        if (this.payload != null) {
+            this.payload.retain(increment);
+        }
+        return this;
+    }
+
+    @Override
+    public UnknownPacket touch() {
+        if (this.payload != null) {
+            this.payload.touch();
+        }
+        return this;
+    }
+
+    @Override
+    public UnknownPacket touch(Object hint) {
+        if (this.payload != null) {
+            this.payload.touch(hint);
+        }
+        return this;
+    }
+
+    @Override
+    public boolean release() {
+        return this.payload == null || this.payload.release();
+    }
+
+    @Override
+    public boolean release(int decrement) {
+        return this.payload == null || this.payload.release(decrement);
+    }
 }