As of 2016 The Ministry of Commerce have declared and announced that bringing in Shishas or Electronic cigarettes into the kingdom in 2016 is prohibited.
They are also using a very old law making possession of them illegal. People have been 'arrested' and taken to the police station usually negated by paying a 'fine' and the equipment confiscated.
I believe it has yet to be tested in the courts.
Plenty of info on Google.