HBaseSaslRpcServer getOrCreateSaslServer() throws IOException {
    if (saslServer == null) {
      saslServer = new HBaseSaslRpcServer(provider, rpcServer.saslProps, rpcServer.secretManager);
    }
    return saslServer;
  }
No protobuf encoding of raw sasl messages
hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/ServerRpcConnection.java