Sufis say they practice tasawwuf and they say it is from the Quran and Sunnah. Should we all view Sufism as Halal or is it haram?

Some Sufi teachings are from Islam, living simple life, for example not accumulating too much wealth and doing dhikr of Allah. However some of their beliefs which in fact forms the real body of belief of Sufism - that human being can become one from Allah - is not from Islam and not acceptable. Some people due to closeness to Allah and being hierarchy can be called to or prayed to in Sufism. This is major shirk and dangerous. There is no difference between one calling to Jeelani or Shia calling to Zain-ul-abideen. This has become the main feature of Sufism today. In the early past there were Sufis who would stay in simple lives and refrain from big gatherings of people. The Naqshabandi have Khidr in their chain. This is common amongst some groups in Malaysia here and the ruler of Brunei is his follower. The founder of Naqashabandi tareeqah or Nazim Haqqani says he can be present in 7 different locations and his Sheikh, in 14 at the same time. The worst danger which comes from this is the intermediacy.