What is the authenticity of the hadith about Assufyani?

The hadith is in Al-Hakim, and Mustadrak, by Ali may Allah be pleased with him. It basically says that the sufyani will be descendant of Khalid bin Yazid bin Abi Sfyan, he will emerge in Damascus, and he will kill many and the killing will be so bad that it will get to a point were women will be sliced open and the infants in them will be killed. The Hadith goes on, it is long, but I wonder what is the authenticity of it.