Universal tweakable Even-Mansour cipher and its applications

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.