Surreptitious Software

2. Methods of Attack and Defense

There is a saying: “If you build a better mouse trap, someone will build a better mouse,” and that could well describe the eternal struggle between Doris and Axel in our surreptitious software scenarios from the last chapter. Axel comes up with a new way to analyze and modify Doris’ code, Doris retaliates with a cleverer watermarking algorithm and additional layers of obfuscation and tamperproofing, which prompts Axel to develop better analysis techniques, and so on. At present we see no end to this escalating war—as of yet there are no theoretical results or practical tools that could put an end to it once and for all, tipping the scales permanently in Doris’ or Axel’s favor, so this situation is simply something ...