Cryptology ePrint Archive: Report 2017/1040

Threshold Implementations of GIFT: A Trade-off Analysis

Naina Gupta and Arpan Jati and Anupam Chattopadhyay and Somitra Kumar Sanadhya and Donghoon Chang

Abstract: Threshold Implementation (TI) is one of the most widely used countermeasure for side channel attacks. Over the years several TI techniques have been proposed for randomizing cipher execution using different variations of secret-sharing and implementation techniques. For instance, Direct Sharing (4-shares) is the most straightforward implementation of the threshold countermeasure. But, its usage is limited due to its high area requirements. On the other hand, sharing using decomposition (3-shares) countermeasure for cubic non-linear functions significantly reduces area and complexity in comparison to 4-shares. Nowadays, security of ciphers using a side channel countermeasure is of utmost importance. This is due to the wide range of security critical applications from smart cards, battery operated IoT devices, to accelerated crypto-processors. Such applications have different requirements (higher speed, energy efficiency, low latency, small area etc.) and hence need different implementation techniques. Although, many TI strategies and implementation techniques are known for different ciphers, there is no single study comparing these on a single cipher. Such a study would allow a fair comparison of the various methodologies. In this work, we present an in-depth analysis of the various ways in which TI can be implemented for a lightweight cipher. We chose GIFT for our analysis as it is currently one of the most energy-efficient lightweight ciphers. The experimental results show that different implementation techniques have distinct applications. For example, the 4-shares technique is good for applications demanding high throughput whereas 3-shares is suitable for constrained environments with less area and moderate throughput requirements. The techniques presented in the paper are also applicable to other block ciphers. For security evaluation, we performed leakage assessment on 3-shares (as it has good area versus speed trade-off) and combined 3-shares (as it uses a new implementation strategy). Experiments using 10 million traces show that the designs are protected against first-order attacks.

Category / Keywords: Side-channel, Threshold Implementation, DPA, CPA, GIFT, TI

Date: received 21 Oct 2017, last revised 30 Sep 2018

Contact author: nainag at iiitd ac in

Available format(s): PDF | BibTeX Citation

Version: 20180930:151556 (All versions of this report)

Short URL: ia.cr/2017/1040