Memory Encryption in Smart Cards

Baris Ege, Elif Bilge Kavun, Tolga Yalcin

10th Smart Card Research and Advanced Application Conference (CARDIS 2011), Leuven, Belgium, Sept. 14-16, 2011


Abstract

With the latest advances in attack methods, it has become increasingly more difficult to secure data stored on smart cards, especially on non-volatile memories (NVMs), which may store sensitive information such as cryptographic keys or program code. Lightweight and low-latency cryptographic modules are a promising solution to this problem. In this study, memory encryption schemes using counter (CTR) and XOR-Encrypt-XOR (XEX) modes of operation are adapted for the target application, and utilized using various implementations of the block ciphers AES and PRESENT. Both schemes are implemented with a block cipher-based address scrambling scheme, as well as a special write counter scheme in order to extend the lifetime of the encryption key in CTR-mode. Using the lightweight cipher PRESENT, it is possible to implement a smart card NVM encryption scheme with less than 6K gate equivalents and zero additional latency.

[DOI] [pdf]

Tags: AES, Low-latency block cipher, Memory encryption, PRESENT, Smart Card