Added check of reserved flags for PUBREL message

netty_parser/src/main/java/org/dna/mqtt/moquette/parser/netty/PubRelDecoder.java

@@ -15,6 +15,13 @@
  */
 package org.dna.mqtt.moquette.parser.netty;
 
+import io.netty.buffer.ByteBuf;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.handler.codec.CorruptedFrameException;
+import io.netty.util.AttributeMap;
+import java.io.UnsupportedEncodingException;
+import java.util.List;
+import org.dna.mqtt.moquette.proto.messages.AbstractMessage;
 import org.dna.mqtt.moquette.proto.messages.MessageIDMessage;
 import org.dna.mqtt.moquette.proto.messages.PubRelMessage;
 
@@ -22,11 +29,31 @@ import org.dna.mqtt.moquette.proto.messages.PubRelMessage;
  *
  * @author andrea
  */
-class PubRelDecoder extends MessageIDDecoder {
-
+class PubRelDecoder extends DemuxDecoder {
+    
     @Override
-    protected MessageIDMessage createMessage() {
-        return new PubRelMessage();
+    void decode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out) throws UnsupportedEncodingException {
+        decode((AttributeMap)ctx, in, out);
+    }
+
+//    @Override
+    void decode(AttributeMap ctx, ByteBuf in, List<Object> out) throws UnsupportedEncodingException {
+        in.resetReaderIndex();
+        //Common decoding part
+        MessageIDMessage message = new PubRelMessage();
+        if (!decodeCommonHeader(message, in)) {
+            in.resetReaderIndex();
+            return;
+        }
+        
+        //if 3.1.1, check the flags (dup, retain and qos == 0)
+        if (message.isDupFlag() || message.isRetainFlag() || message.getQos() != AbstractMessage.QOSType.LEAST_ONE) {
+            throw new CorruptedFrameException("Received a PURREL with fixed header flags != b0010");
+        }
+        
+        //read  messageIDs
+        message.setMessageID(in.readUnsignedShort());
+        out.add(message);
     }
 
 }