XMX: A Firmware-Oriented Block Cipher Based on Modular Multiplications

Abstract. This paper presents xmx, a new symmetric block cipher optimized for public-key libraries and microcontrollers with arithmetic coprocessors. xmx has no S-boxes and uses only modular multiplications and xors. The complete scheme can be described by a couple of compact formulae that offer several interesting time-space trade-offs (number of rounds/key-size for constant security). In practice, xmx appears to be tiny and fast: 136 code bytes and a 121 kilo-bits/second throughput on a Siemens SLE44CR80s smart-card (5 MHz oscillator).

• Type: Conference
• Year: 1997
• Where: FSE
• Authors: David M'Raïhi, David Naccache, Jacques Stern, Serge Vaudenay
• Keywords: Cryptology, FSE 1997, Interesting Time-space Trade-offs, Modular Multiplications, Symmetric Block Cipher