Paper 2024/1787

An Efficient and Secure Boolean Function Evaluation Protocol

Abstract

Boolean functions play an important role in designing and analyzing many cryptographic systems, such as block ciphers, stream ciphers, and hash functions, due to their unique cryptographic properties such as nonlinearity, correlation immunity, and algebraic properties. The secure evaluation of Boolean functions or Secure Boolean Evaluation (SBE) is an important area of research. SBE allows parties to jointly compute Boolean functions without exposing their private inputs. SBE finds applications in privacy-preserving protocols and secure multi-party computations. In this manuscript, we present an efficient and generic two-party protocol (namely $\textsf{BooleanEval}$) for the secure evaluation of Boolean functions by utilizing a 1-out-of-2 Oblivious Transfer (OT) as a building block. $\textsf{BooleanEval}$ only employs XOR operations as the core computational step, thus making it lightweight and fast. Unlike other lightweight state-of-the-art designs of SBE, $\textsf{BooleanEval}$ avoids the use of additional cryptographic primitives, such as hash functions and commitment schemes to reduce the computational overhead.