Functional Signcryption: Notion, Construction, and Applications

Functional encryption (FE) enables sophisticated control over decryption rights in a multi-user scenario, while functional signature (FS) allows to enforce complex constraints on signing capabilities. This paper introduces the concept of functional signcryption (FSC) that aims to provide the functionalities of both FE and FS in an unified cost-effective primitive. FSC provides a solution to the problem of achieving confidentiality and authenticity simultaneously in digital communication and storage systems involving multiple users with better efficiency compared to a sequential implementation of FE and FS. We begin by providing formal definition of FSC and formulating its security requirements. Next, we present a generic construction of this challenging primitive that supports arbitrary polynomial-size signing and decryption functions from known cryptographic building blocks, namely, indistinguishability obfuscation (IO) and statistically simulation-sound noninteractive zero-knowle...

• Type: Journal
• Year: 2015
• Where: PROVSEC
• Authors: Pratish Datta, Ratna Dutta, Sourav Mukhopadhyay
• Keywords: PROVSEC 2015, Security Privacy