Cryptology ePrint Archive: Report 2006/275

A New Mode of Encryption Providing A Tweakable Strong Pseudo-Random

Debrup Chakraborty and Palash Sarkar

Abstract: We present PEP, which is a new construction of a tweakable strong pseudo-random permutation. PEP uses a hash-encrypt-hash approach which has recently been used in the construction of HCTR. This approach is different from the encrypt-mask-encrypt approach of constructions such as CMC, EME and EME$^*$. The general hash-encrypt-hash approach was earlier used by Naor-Reingold to provide a generic construction technique for an SPRP (but not a tweakable SPRP). PEP can be seen as the development of the Naor-Reingold approach into a fully specified mode of operation with a concrete security reduction for a tweakable strong pseudo-random permutation. The security bound of HCTR which is also based on the Naor-Reingold approach is weaker than that of PEP. Compared to previous known constructions, PEP is the only construction of tweakable SPRP which uses a single key, is efficiently parallelizable and can handle an arbitrary number of blocks.

Category / Keywords: secret-key cryptography / mode of operation, tweakable encryption, strong pseudo-random permutation

Publication Info: A short version of this paper apperas in the proceedings of FSE 2006, LNCS 4047

Date: received 16 Aug 2006

Contact author: debrup at delta cs cinvestav mx

Available format(s): Postscript (PS) | Compressed Postscript (PS.GZ) | PDF | BibTeX Citation

Version: 20060817:085829 (All versions of this report)

Short URL: ia.cr/2006/275

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