No. You cannot park your tent at white land. And if you want to do so you will be needing the permission which you can take locally and will be difficult to get. However, you can stay there at tent hotels they provide there.
Rann utsav has ended already. But for the future , you cannot pitch it on the white desert. You can surely pitch your tent 30kms far a sand dune area near kalo dungar !. There no permissions are required.