Privacy preserving signcryption scheme

Abstract

Signcryption is a public-key cryptographic primitive that is a synthesis of encryption and digital signature schemes. We present a signcryption scheme using anonymous attribute based encryption. The scheme uses the notion of identity-based digital signature on the message encrypted under the attribute based encryption scheme. The scheme provides both sender and receiver anonymity, in particular, only the legitimate receiver can identify the sender after the successful decryption operation. We show that the scheme is secure against adaptive chosen ciphertext attack and chosen message attack.