@Override
  protected void channelRead0(ChannelHandlerContext ctx, ByteBuf msg) throws Exception {
    byte[] bytes = new byte[msg.readableBytes()];
    msg.readBytes(bytes);
    ctx.fireChannelRead(Unpooled.wrappedBuffer(unwrapper.unwrap(bytes, 0, bytes.length)));
  }
Unwrap sasl messages. Should be placed after a
io.netty.handler.codec.LengthFieldBasedFrameDecoder
hbase-client/src/main/java/org/apache/hadoop/hbase/security/SaslUnwrapHandler.java