An OAEP Variant With a Tight Security Proof

Jakob Jonsson

Paper 2002/034 Original: eprint.iacr.org/2002/034 ↗

An OAEP Variant With a Tight Security Proof

Jakob Jonsson

Abstract

We introduce the OAEP++ encoding method, which is an adaptation of the OAEP encoding method, replacing the last step of the encoding operation with an application of a block cipher such as AES. We demonstrate that if $f$ is a one-way trapdoor function that is hard to invert, then OAEP++ combined with $f$ is secure against an IND-CCA2 adversary in the random oracle model. Moreover, the security reduction is tight; an adversary against $f$-OAEP++ can be extended to an $f$-inverter with a running time linear in the number of oracle queries.

Metadata

Available format(s): PDF
Category: Public-key cryptography
Publication info: Preprint.
History: 2002-03-18: last updated; 2002-03-18: published
Short URL: https://ia.cr/2002/034
License: https://creativecommons.org/licenses/by/4.0/

BibTeX

@misc{cryptoeprint:2002/034,
      author = {Jakob Jonsson},
      title = {An OAEP Variant With a Tight Security Proof},
      howpublished = {Cryptology {ePrint} Archive, Paper 2002/034},
      year = {2002},
      url = {https://eprint.iacr.org/2002/034}
}