T-Scope: Side-channel Leakage Assessment with a Hardware-accelerated Online TVLA Test

Test vector leakage assessment (TVLA) is a generic and commonly-used approach to assessing a device's side-channel vulnerability based on measuring a large number power traces. However, the current use model of TVLA uses batch processing which separates trace acquisition from statistical analysis, making the method harder to use in online, continuous-monitoring scenarios. We propose T-scope, a TVLA optimized for online testing of real-time targets. We use a pipelined solution to efficiently store power traces in compact histogram structures, and then use FPGA-based hardware acceleration of Welch's t-test to compute the TVLA. By continuously updating the histograms with newly acquired power traces, T-scope visualizes real-time changes in the side-channel leakage characteristics of the target. Our FPGA-based hardware-accelerator, created using high-level synthesis, offers a 99.93X performance gain over a software-based solution. We present a hardware demonstrator of a real-time display of the TVLA assessment of a leaky implementation of the Advanced Encryption Standard.