Tamper-proofing Software Watermarking Scheme Based on Constant Encoding

A novel tamper-proofing software watermarking scheme is proposed based on CLOC encoding of PPCT and constant tamper-proofing technology. This scheme constructs a many-to-one function with the watermark pieces and encodes the results of the function into constants as the parameters of opaque predicates, then distributes them in the program, which leads to the interaction of the watermark pieces. The situation of one or more pieces destroyed can be felt due to the interaction characteristic and then the program will not work correctly, which improves the watermarks tamper-proofing ability. The experiment shows that the performance of the scheme is good and can resist many kinds of attacks.