| Autor: |
Alex Biryukov, Baptiste Lambin, Aleksei Udovenko |
| Jazyk: |
angličtina |
| Rok vydání: |
2023 |
| Předmět: |
|
| Zdroj: |
Transactions on Cryptographic Hardware and Embedded Systems, Vol 2023, Iss 3 (2023) |
| Druh dokumentu: |
article |
| ISSN: |
2569-2925 |
| DOI: |
10.46586/tches.v2023.i3.97-135 |
| Popis: |
At CRYPTO’22, Ranea, Vandersmissen, and Preneel proposed a new way to design white-box implementations of ARX-based ciphers using so-called implicit functions and quadratic-affine encodings. They suggest the Speck block-cipher as an example target. In this work, we describe practical attacks on the construction. For the implementation without one of the external encodings, we describe a simple algebraic key recovery attack. If both external encodings are used (the main scenario suggested by the authors), we propose optimization and inversion attacks, followed by our main result - a multiple-step round decomposition attack and a decomposition-based key recovery attack. Our attacks only use the white-box round functions as oracles and do not rely on their description. We implemented and verified experimentally attacks on white-box instances of Speck-32/64 and Speck-64/128. We conclude that a single ARX-round is too weak to be used as a white-box round. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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