LLWM & IR-Mark: Integrating Software Watermarks into an LLVM-based Framework

While software protection mechanisms, such as DRM and online services, hinder the unrestrained duplication of games and applications, these mechanisms fail at protecting individual software components from reuse by intellectual property thieves. While conceptually watermarking can discourage software misuse and allows proof of ownership, embedding watermarks requires expert knowledge. This is why software watermarks are barely used. This paper presents LLWM, an LLVM-based watermarking framework that automates the embedding of watermarks and thus enables the widespread use of watermarking. LLWM incorporates several (adapted) implementations of existing watermarking techniques and provides the foundation for IR-Mark, a new watermarking technique based on a modified register allocation. With LLWM, built upon LLVM and its compiler Clang, developers can use a watermark simply by compiling their codes, without the obstacle of having to understand and run existing methods and standalone tools. With the methods included in LLWM, we offer a variety of choices for embedding techniques and evaluate and discuss their characteristics and resilience against common attacks.