Surreptitious Software

8. Software Watermarking

In the last few chapters, we have shown you techniques you can use to prevent an attacker from deciphering the inner workings of your program or from modifying it. But what happens if these lines of defenses fail? In this chapter, we will discuss software watermarking—a technique for embedding a unique identifier into the executable of a program. A watermark is much like a copyright notice; it asserts that you claim certain rights to the program. Just like the copyright notice in this book won’t prevent you from making photocopies for all your friends,¹ the presence of this unique identifier in your program won’t prevent an attacker from reverse engineering it or pirating it. However, if the identifier continues to exist ...