This paper describes a generalized tweakable blockcipher HPH （Hash-Permutation-Hash）, which is based ona public random permutation P and a family of almost-XOR-universal hash functions H={HK}K∈κ as a tweak and key...This paper describes a generalized tweakable blockcipher HPH （Hash-Permutation-Hash）, which is based ona public random permutation P and a family of almost-XOR-universal hash functions H={HK}K∈κ as a tweak and keyschedule, and defined as y = HPHK（（t1, t2）, x） = P（x HK（t1）） HK（t2）, where K is a key randomly chosen from a keyspace/C, （tl, t2） is a tweak chosen from a valid tweak space T, x is a plaintext, and y is a ciphertext. We prove that HPHis a secure strong tweakable pseudorandom permutation （STPRP） by using H-coefficients technique. Then we focus on thesecurity of HPH against multi-key and related-key attacks. We prove that HPH achieves both multi-key STPRP security andrelated-key STPRP security. HPH can be extended to wide applications. It can be directly applied to authentication andauthenticated encryption modes. We apply HPH to PMAC1 and OPP, provide an improved authentication mode HPMACand a new authenticated encryption mode OPH, and prove that the two modes achieve single-key security, multi-key security,and related-key security.展开更多
The construction of the tweakable Even-Mansour cipher is in fact the designs of permutations,mask operations,and masking functions.For information-theoretic security,permutations are usually taken as random permutatio...The construction of the tweakable Even-Mansour cipher is in fact the designs of permutations,mask operations,and masking functions.For information-theoretic security,permutations are usually taken as random permutations.This paper focuses on the mask operations and masking functions to construct a universal tweakable Even-Mansour cipher.Firstly,we describe a formal definition of a universal masking function and provide a universal tweakable Even-Mansour cipher UTEM.In the random permutation model,we prove that UTEM is multi-key secure by H-coefficients technique.Then we show some efficient instantiations of the universal masking function to concertize UTEM.Finally,we apply UTEM to an encryption mode TIE(tweak incrementation encryption)and an authenticated encryption mode IAPM(integrity aware parallelizable mode),present two new schemes TIE-plus and IAPM-plus,and prove their security.UTEM enriches tweakable blockciphers,brings more research topics,and plays an important role in modes of operation,which will be of great significance.展开更多
基金This work was supported by the National Natural Science Foundation of China under Grant Nos. 61522210 and 61632013,
文摘This paper describes a generalized tweakable blockcipher HPH （Hash-Permutation-Hash）, which is based ona public random permutation P and a family of almost-XOR-universal hash functions H={HK}K∈κ as a tweak and keyschedule, and defined as y = HPHK（（t1, t2）, x） = P（x HK（t1）） HK（t2）, where K is a key randomly chosen from a keyspace/C, （tl, t2） is a tweak chosen from a valid tweak space T, x is a plaintext, and y is a ciphertext. We prove that HPHis a secure strong tweakable pseudorandom permutation （STPRP） by using H-coefficients technique. Then we focus on thesecurity of HPH against multi-key and related-key attacks. We prove that HPH achieves both multi-key STPRP security andrelated-key STPRP security. HPH can be extended to wide applications. It can be directly applied to authentication andauthenticated encryption modes. We apply HPH to PMAC1 and OPP, provide an improved authentication mode HPMACand a new authenticated encryption mode OPH, and prove that the two modes achieve single-key security, multi-key security,and related-key security.
基金supported by the National Key Research and Development Program of China(2019YFB2101704)National Natural Science Foundation of China(Grant Nos.61902195 and 62102196)NUPTSF(NY219131).
文摘The construction of the tweakable Even-Mansour cipher is in fact the designs of permutations,mask operations,and masking functions.For information-theoretic security,permutations are usually taken as random permutations.This paper focuses on the mask operations and masking functions to construct a universal tweakable Even-Mansour cipher.Firstly,we describe a formal definition of a universal masking function and provide a universal tweakable Even-Mansour cipher UTEM.In the random permutation model,we prove that UTEM is multi-key secure by H-coefficients technique.Then we show some efficient instantiations of the universal masking function to concertize UTEM.Finally,we apply UTEM to an encryption mode TIE(tweak incrementation encryption)and an authenticated encryption mode IAPM(integrity aware parallelizable mode),present two new schemes TIE-plus and IAPM-plus,and prove their security.UTEM enriches tweakable blockciphers,brings more research topics,and plays an important role in modes of operation,which will be of great significance.
