Cryptology ePrint Archive: Report 2015/512

Efficient Key Extraction from the Primary Side of a Switched-Mode Power Supply

Sami Saab, Andrew Leiserson, and Michael Tunstall

Abstract: In this paper we detail techniques that can be used to analyze and attack an AES implementation on an FPGA from the primary (i.e., external) side of a switched-mode power supply. Our attack only requires measurements of the duty cycle of the power supply, and then increases the signal-to-noise ratio (SNR) though averaging, deconvolution and wavelet based detrending. The result is an exploitable source of leakage that allows a secret key to be determined from low-frequency power measurements. The techniques and procedures provide a general approach to performing differential power analysis (DPA) from a single point of information for any single hypothesized intermediate value, suggesting their potential for improving other types of side-channel analysis as well.

Category / Keywords: implementation / Side-Channel Analysis, DPA, Switched-Mode Power Supply, Deconvolution, Detrending, Wavelets

Date: received 27 May 2015, last revised 28 May 2015

Contact author: sami saab at cryptography com

Available format(s): PDF | BibTeX Citation

Version: 20150528:201732 (All versions of this report)

Short URL: ia.cr/2015/512

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