A New Concept of Hash Functions SNMAC Using a Special Block Cipher and NMAC/HMAC Constructions

摘要: In this paper, we present new security proofs of well-known hash constructions NMAC/HMAC proposed by Bellare et al. in 1996. We show that block ciphers should be used functions another way than it has been so far. introduce a cryptographic primitive called special cipher (SBC) which is resistant to attacks specific for functions. propose use SBC the constructions, what gives rise concept Special NMAC (SNMAC). From our follows SNMAC are computationally preimage and collision attacks. Moreover, at CRYPTO 2005 Coron proved indifferentiable from random oracle limit. construction general enables various proposals using different instances ciphers. DN (Double Net) define function HDN (Hash Double as based on DN.