Visible to the public Biblio

Filters: Author is Kar, Monodeep  [Clear All Filters]
2020-01-20
Chawla, Nikhil, Singh, Arvind, Rahman, Nael Mizanur, Kar, Monodeep, Mukhopadhyay, Saibal.  2019.  Extracting Side-Channel Leakage from Round Unrolled Implementations of Lightweight Ciphers. 2019 IEEE International Symposium on Hardware Oriented Security and Trust (HOST). :31–40.

Energy efficiency and security is a critical requirement for computing at edge nodes. Unrolled architectures for lightweight cryptographic algorithms have been shown to be energy-efficient, providing higher performance while meeting resource constraints. Hardware implementations of unrolled datapaths have also been shown to be resistant to side channel analysis (SCA) attacks due to a reduction in signal-to-noise ratio (SNR) and an increased complexity in the leakage model. This paper demonstrates optimal leakage models and an improved CFA attack which makes it feasible to extract first-order side-channel leakages from combinational logic in the initial rounds of unrolled datapaths. Several leakage models, targeting initial rounds, are explored and 1-bit hamming weight (HW) based leakage model is shown to be an optimal choice. Additionally, multi-band narrow bandpass filtering techniques in conjunction with correlation frequency analysis (CFA) is demonstrated to improve SNR by up to 4×, attributed to the removal of the misalignment effect in combinational logics and signal isolation. The improved CFA attack is performed on side channel signatures acquired for 7-round unrolled SIMON datapaths, implemented on Sakura-G (XILINX spartan 6, 45nm) based FPGA platform and a 24× reduction in minimum-traces-to-disclose (MTD) for revealing 80% of the key bits is demonstrated with respect to conventional time domain correlation power analysis (CPA). Finally, the proposed method is successfully applied to a fully-unrolled datapath for PRINCE and a parallel round-based datapath for Advanced Encryption Standard (AES) algorithm to demonstrate its general applicability.

2017-11-13
Kar, Monodeep, Singh, Arvind, Mathew, Sanu, Rajan, Anand, De, Vivek, Mukhopadhyay, Saibal.  2016.  Exploiting Fully Integrated Inductive Voltage Regulators to Improve Side Channel Resistance of Encryption Engines. Proceedings of the 2016 International Symposium on Low Power Electronics and Design. :130–135.

This paper explores fully integrated inductive voltage regulators (FIVR) as a technique to improve the side channel resistance of encryption engines. We propose security aware design modes for low passive FIVR to improve robustness of an encryption-engine against statistical power attacks in time and frequency domain. A Correlation Power Analysis is used to attack a 128-bit AES engine synthesized in 130nm CMOS. The original design requires \textasciitilde250 Measurements to Disclose (MTD) the 1st byte of key; but with security-aware FIVR, the CPA was unsuccessful even after 20,000 traces. We present a reversibility based threat model for the FIVR-based protection improvement and show the robustness of security aware FIVR against such threat.