Cryptology ePrint Archive: Report 2007/014

Invertible Universal Hashing and the TET Encryption Mode

Shai Halevi

Abstract: This work describes a mode of operation, TET, that turns a regular block cipher into a length-preserving enciphering scheme for messages of (almost) arbitrary length. When using an n-bit block cipher, the resulting scheme can handle input of any bit-length between n and 2^n and associated data of arbitrary length.

The mode TET is a concrete instantiation of the generic mode of operation that was proposed by Naor and Reingold, extended to handle tweaks and inputs of arbitrary bit length. The main technical tool is a construction of invertible ``universal hashing'' on wide blocks, which is as efficient to compute and invert as polynomial-evaluation hash.

Category / Keywords: secret-key cryptography /

Publication Info: Extended abstract appears in the proceedings of CRYPTO 2007

Date: received 12 Jan 2007, last revised 24 May 2007

Contact author: shaih at alum mit edu

Available format(s): PDF | BibTeX Citation

Version: 20070524:134457 (All versions of this report)

Short URL: ia.cr/2007/014

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