I really don't know how they legalize or i-legalize such thing as bitcoin because you are using it with your own internet and computer hardware maybe they just not supporting it before but every citizen of India can use it no matter what happens unless their government issue a criminal liabilities in using bitcoin.
I think no countries that rules as bitcoin holders as criminals. Holding bitcoin is right. Using bitcoin for transaction is prohibited in several countries . Even buy and sell using USD is illegal. some countries should use their own currency.