Service tax & cst both

Sir,

We have an agreement with Maharastra based party/ suppliers. The party/ supplier has provided  temporary mansoon /weather sheds in our premises situated in U.P. with all his materials. Suppliers charging the amount for shed on per square ft rate (as per agrrement). Now he is charging Service Tax @ 12.36% on amount plus CST @ 12.5% on subtotal i.e amount+Ser.Tax. The calculations are as under:-

Amount charged for shed  Rs.100.00

Service tax @ 12.36           Rs.12.36

CST @ 12.5%                     Rs.14.05

Total Bill amt                      Rs.126.41

I just want to know, whether is it as per law??

Respected experts are requested to please suggest.

Thank you

Ashok kr Pandey