Oblivious checking of a digital good is performed by identifying a plurality of key instructions within a function of a digital good. Each key instruction is an instruction that possibly modifies a register or a flag. An extra instruction is then inserted into the function for each of the key instructions. The extra instructions each correspond to one of the key instructions and modify a register in a deterministic fashion based on the corresponding key instruction. A set of inputs to the function are then identified that result in different valid computation paths in the function being taken. A checksum for the function is then generated by using a mapping function which maps the contents of the register to the set of inputs.