ECGSC: Elliptic curve based generalized signcryption

Abstract

Signcryption is a new cryptographic primitive that simultaneously fulfills both the functions of signature and encryption. The definition of Generalized Signcryption is proposed in the paper firstly. Generalized Signcryption has a special feature that provides confidentiality or authenticity separately under the condition of specific inputs. Based on ECDSA, a Signcryption scheme called ECGSC is designed. It will be equivalent to an AtE(OTP$, MAC) encryption scheme or ECDSA when one of party is absent. A third party can verify the Signcryption text publicly in the method of ECDSA. Security properties are proven based on Random Oracle mode: confidentiality (CUF-CPA), unforgeability (UF-CMA) and non-repudiation. Compared with the others, ECGSC presents a 78% reduction in computational cost for typical security parameters for high level security applications. © Springer-Verlag Berlin Heidelberg 2006.