Welcome to the resource topic for 2012/131
Title:
Composition Theorems for CCA Cryptographic Security
Authors: Rodolphe Lampe, Jacques Patarin
Abstract:We present two new theorems to analyze the indistinguishability of the composition of cryptographic permutations and the indistinguishability of the XOR of cryptographic functions. Using the H Coefficients technique of \cite{Patarin-2001}, for any two families of permutations F and G with CCA distinghuishability advantage \leq\alpha_F and \leq\alpha_G, we prove that the set of permutations f\circ g, f\in F, g\in G has CCA distinguishability advantage \leq\alpha_F\times\alpha_G. This simple composition result gives a CCA indistinguishability geometric gain when composing blockciphers (unlike previously known clasical composition theorems). As an example, we apply this new theorem to analyze 4r and 6r rounds Feistel schemes with r\geq 1 and we improve previous best known bounds for a certain range of queries. Similarly, for any two families of functions F and G with distinghuishability advantage \leq\alpha_F and \leq\alpha_G, we prove that the set of functions f\oplus g, f\in F, g\in G has distinguishability advantage \leq\alpha_F\times\alpha_G. As an example, we apply this new theorem to analyze the XOR of 2r permutations and we improve the previous best known bounds for certain range of queries
ePrint: https://eprint.iacr.org/2012/131
See all topics related to this paper.
Feel free to post resources that are related to this paper below.
Example resources include: implementations, explanation materials, talks, slides, links to previous discussions on other websites.
For more information, see the rules for Resource Topics .