Paper 2021/1252
Complete Practical Side-Channel-Assisted Reverse Engineering of AES-Like Ciphers
Andrea Caforio, Fatih Balli, and Subhadeep Banik
Abstract
Public knowledge about the structure of a cryptographic system is a standard assumption in the literature and algorithms are expected to guarantee security in a setting where only the encryption key is kept secret. Nevertheless, undisclosed proprietary cryptographic algorithms still find widespread use in applications both in the civil and military domains. Even though side-channel-based reverse engineering attacks that recover the hidden components of custom cryptosystems have been demonstrated for a wide range of constructions, the complete and practical reverse engineering of AES-128-like ciphers remains unattempted. In this work, we close this gap and propose the first practical reverse engineering of AES-128-like custom ciphers, i.e., algorithms that deploy undisclosed SubBytes, ShiftRows and MixColumns functions. By performing a side-channel-assisted differential power analysis, we show that the amount of traces required to fully recover the undisclosed components are relatively small, hence the possibility of a side-channel attack remains as a practical threat. The results apply to both 8-bit and 32-bit architectures and were validated on two common microcontroller platforms.
Metadata
- Available format(s)
-
PDF
- Category
- Implementation
- Publication info
- Published elsewhere. CARDIS-2021
- Keywords
- side-channelDPAreverse engineeringAES
- Contact author(s)
-
andrea caforio @ epfl ch
fatih balli @ csem ch
subhadeep banik @ epfl ch - History
- 2021-09-20: received
- Short URL
- https://ia.cr/2021/1252
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2021/1252,
author = {Andrea Caforio and Fatih Balli and Subhadeep Banik},
title = {Complete Practical Side-Channel-Assisted Reverse Engineering of {AES}-Like Ciphers},
howpublished = {Cryptology {ePrint} Archive, Paper 2021/1252},
year = {2021},
url = {https://eprint.iacr.org/2021/1252}
}