Hash Functions and Message Authentication

This chapter is concerned with mechanisms for data integrity, specifically hash functions and message authentication codes. It discusses design techniques for hash functions, including iterated hash functions and the sponge construction. The chapter introduces concepts of security for hash functions, in particular, the idea of collision resistance. It introduces the important design technique of iterated hash functions. The chapter provides a treatment of message authentication codes, where the authors again present some general constructions and security proofs. Unconditionally secure MACs, and their construction using strongly universal hash families. Many commonly used hash functions have been constructed using the Merkle-Damgard approach. Strongly universal hash families are used in several areas of cryptography. It proves some lower bounds on deception probabilities of unconditionally secure MACs, which show that the authentication codes derived from strongly universal hash families have minimum possible deception probabilities.