Support files for paper "Racing against the clock: side-channel leakage from crossing asynchronous clock domains"

Note that results will differ slightly each time (and from the tables in the paper) due to outlier removal using a random sampling approach to establish the median, and standard numerical precision.

How to run

Clone/extract the repository. Then, in the src folder, create and activate a virtual environment, install the requirements, and run the runall.sh script to generate all figures (as PNG) and a markdown representation of the tables.

cd src
python -m venv .venv
source .venv/bin/activate
pip install -r requirements.txt
./runall.sh

This has been tested on MacOS 15, Python 3.13.5.

Items covered:

initial_investigation.py

• Fig 2/3/16/17: comparison of activity against RAPL, clock ratio, CLOCK_MONOTONIC, RDTSC
• Table 1: Comparison of spin and sha

instructions

• Table 2: Comparison of pairwise t-values for different instructions

Operands

• Table 3: Comparison of multiplication by all-0 vs. all-1

imx_original

• Figure 4: Leakage behaviour on i.MXRT1166 processor - Violin plot and correlation progression

fpga_frequencies

• Figure 8: Experiments on FPGA over different memory clock frequencies - variability and t-values
• Table 4: Comparison of different frequencies on FPGA with significant leakage
• Figure 9: Distribution of measurements for HW0 (blue) and HW8 (orange) at different frequencies, highlighting substantial difference at asynchronous clock

fpga_cpa

• Figure 10: CPA convergence traces for toy-cipher on FPGA platform

dma_timer_nop_add.py

• Figure 11: Timer delta capture through DMA over time for NOP and ADD

covert_channel.py

• Figure 12: Average of 10 000 interpolated traces after filtering, showing the ability to make a covert channel

modexp_attack.py and modexp_attack_plot.py

• Figure 13: Attack on sections of 512-bit key. The correct key bits are annotated at the bottom of each plot.

imx_tiny_aes.py

• Figure 15: CPA convergence on first SubBytes over 545 000 traces on i.MX RT1166x