
Protect white‐box AES to resist table composition attacks
Author(s) -
Bai Kunpeng,
Wu Chuankun,
Zhang Zhenfeng
Publication year - 2018
Publication title -
iet information security
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.308
H-Index - 34
eISSN - 1751-8717
pISSN - 1751-8709
DOI - 10.1049/iet-ifs.2017.0046
Subject(s) - computer science , white box , cryptography , s box , cryptanalysis , key (lock) , lookup table , context (archaeology) , block cipher , table (database) , aes implementations , theoretical computer science , computer security , advanced encryption standard , arithmetic , operating system , mathematics , database , software engineering , paleontology , biology
White‐box cryptography protects cryptographic software in a white‐box attack context (WBAC), where the dynamic execution of the cryptographic software is under full control of an adversary. Protecting AES in the white‐box setting attracted many scientists and engineers, and several solutions emerged. However, almost all these solutions have been badly broken by various efficient white‐box attacks, which target compositions of key‐embedding lookup tables. In 2014, Luo, Lai, and You proposed a new WBAC‐oriented AES implementation, and claimed that their implementation is secure against both Billet et al . 's attack and De Mulder et al . 's attack. In this study, based on the existing table‐composition‐targeting cryptanalysis techniques, the authors show that the secret key of the Luo–Lai–You (LLY) implementation can be recovered with a time complexity of about 2 44 . Furthermore, the authors propose a new white‐box AES implementation based on table lookups, which is shown to be resistant against the existing table‐composition‐targeting white‐box attacks. The authors, key‐embedding tables are obfuscated with large affine mappings, which cannot be cancelled out by table compositions of the existing cryptanalysis techniques. Although their implementation requires twice as much memory as the LLY WBAES to store the tables, its speed is about 63 times of the latter.