ML-augmented Methodology for Fast Thermal Side-channel Emission Analysis.

Accurate side-channel attacks can non-invasively or semi-invasively extract secure information from hardware devices using "side- channel" measurements. The thermal profile of an IC is one class of side channel that can be used to exploit the security weaknesses in a design. Measurement of junction temperature from an on-chip thermal sensor or top metal layer temperature using an infrared thermal image of an IC with the package being removed can disclose secret keys of a cryptographic design through correlation power analysis. In order to identify the design vulnerabilities to thermal side channel attacks, design time simulation tools are highly important. However, simulation of thermal side-channel emission is highly complex and computationally intensive due to the scale of simulation vectors required and the multi-physics simulation models involved. Hence, in this paper, we have proposed a fast and comprehensive Machine Learning (ML) augmented thermal simulation methodology for thermal Side-Channel emission Analysis (SCeA). We have developed an innovative tile-based Delta-T Predictor using a data-driven DNN-based thermal solver. The developed tile based Delta-T Predictor temperature is used to perform the thermal side-channel analysis which models the scenario of thermal attacks with the measurement of junction temperature. This method can be 100-1000x faster depending on the size of the chip compared to traditional FEM-based thermal solvers with the same level of accuracy. Furthermore, this simulation allows for the determination of location- dependent wire temperature on the top metal layer to validate the scenario of thermal attack with top metal layer temperature. We have demonstrated the leakage of the encryption key in an 128-bit AES chip using both proposed tile-based temperature calculations and top metal wire temperature calculations, quantified by simulation MTD (Measurements-to-Disclosure).