We showcase the chi-squared method on some examples. In particular: (1) We prove an optimal bound of $q/2^n$ for the XOR of two permutations, and our proof considerably simplifies previous approaches using the $H$-coefficient method, (2) we provide improved bounds for the recently proposed encrypted Davies-Meyer PRF construction by Cogliati and Seurin (CRYPTO '16), and (3) we give a tighter bound for the Swap-or-not cipher by Hoang, Morris, and Rogaway (CRYPTO '12).
Category / Keywords: Symmetric cryptography, information-theoretic indistinguishability, provable security Original Publication (in the same form): IACR-CRYPTO-2017 Date: received 5 Jun 2017, last revised 22 Feb 2018 Contact author: hviettung at gmail com Available format(s): PDF | BibTeX Citation Note: The proceeding version of this paper contains a glitch in the proof of the XOR construction, which is corrected in this version. Version: 20180222:162822 (All versions of this report) Short URL: ia.cr/2017/537 Discussion forum: Show discussion | Start new discussion