Side-channel watermarks for embedded software

In this paper we introduce a new software watermarking mechanism for the embedded environment. The newly proposed software watermarking mechanism can be added at the assembly level and hides the watermark in the power consumption of the device. By using side-channel analysis techniques, the verifier can reliably detect his watermark in the power traces of the device. This new approach is especially well suited for embedded microcontrollers that have program memory protection. In comparison to other software watermark mechanisms a verifier does not need to have access to the software code or data memory to detect the watermark. This makes the detection of the watermarks very efficient for embedded applications in which access to the program code or data memory is very restricted. Our watermark method can therefore serve as a very easy and cost efficient way to detect software theft for embedded applications.