International Association for Cryptologic Research
OAEP and other similar schemes proven secure in Random-Oracle Model require one or more hash functions with output size larger than those of standard hash functions. In this paper, the authors show that by utilizing popular Sponge constructions in OAEP framework, they can eliminate the need of such hash functions. They provide a new scheme in OAEP framework based on Sponge construction and call their scheme Sponge based Asymmetric Encryption Padding (SpAEP). SpAEP is based on 2 functions: Sponge and SpongeWrap and requires only standard output sizes proposed and standardized for Sponge functions.