Mercy: A Fast Large Block Cipher for Disk Sector Encryption

Abstract. We discuss the special requirements imposed on the underlying cipher of systems which encrypt each sector of a disk partition independently, and demonstrate a certificational weakness in some existing block ciphers including Bellare and Rogaway's 1999 proposal, proposing a new quantitative measure of avalanche. To address these needs, we present Mercy, a new block cipher accepting large (4096-bit) blocks, which uses a key-dependent state machine to build a bijective F function for a Feistel cipher. Mercy achieves 9 cycles/byte on a Pentium compatible processor.

• Type: Conference
• Year: 2000
• Where: FSE
• Authors: Paul Crowley
• Keywords: Block Cipher, Cryptology, Feistel Cipher, FSE 2000, Rogaway's 1999 Proposal