code: function(state,isInv)
  		{
  			for (var i = 0; i < 16; i++)
  				state[i] = isInv?this.rsbox[state[i]]:this.sbox[state[i]];
  			return state;
  		}
docs: /* substitute all the values from the state with the value in the SBox
  using the state value as index for the SBox