We design a practical and provablysecure block ciper over small domain and non-binary inputs,which is also can be considered as a pseudorandom permutation on N elements.Our work is based on a relation we found between...We design a practical and provablysecure block ciper over small domain and non-binary inputs,which is also can be considered as a pseudorandom permutation on N elements.Our work is based on a relation we found between the small domain ciper and the negative hypergeometric probability(NHG) distribution.We prove that our block ciper achieves ideal security,that is,it is indistinguishable from a random permutation even if the adversary had already observed N plaintext-cipertext pairs.In particular,we initiate an efficient and sufficiently precise sampling algorithm for negative hypergeometric distribution.展开更多
基金National 973 Fundamental Basic Research Program under grant No.2014CB340600 and by the National Natural Science Foundations of China
文摘We design a practical and provablysecure block ciper over small domain and non-binary inputs,which is also can be considered as a pseudorandom permutation on N elements.Our work is based on a relation we found between the small domain ciper and the negative hypergeometric probability(NHG) distribution.We prove that our block ciper achieves ideal security,that is,it is indistinguishable from a random permutation even if the adversary had already observed N plaintext-cipertext pairs.In particular,we initiate an efficient and sufficiently precise sampling algorithm for negative hypergeometric distribution.