Cryptography Stack Exchange
Cryptography Stack Exchange

Questions tagged [shuffle]

12 questions
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EC scalar multiplication and shuffling

Problem Alice has an array of random EC points $P_{1},...,P_{n}$ (their logarithms are not known neither to Alice nor to Bob). She sends them to Bob. Bob multiplies them all by a secret number $x$, suffles them and sends the resulting array…
artelk
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Deterministic shuffling algorithm

Is there a well know (cryptographically secure) algorithm to shuffle a vector of values, deterministically, without using any randomness, such that it is hard (or as hard as possible) to guess its initial configuration? The goal is to achieve an…
raugfer
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What is the difference between a permutation and a shuffle (transposition cipher)

A non-cryptographic definition of a permutation is "2a: the act or process of changing the lineal order of an ordered set of objects. 2b: an ordered arrangement of a set of objects The Wikipedia article on Random permutation states that "A good…
SAI Peregrinus
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Fisher Yates on "faulted" random number generator cryptanalysis

For the sake of curiosity and fun, i have implemented a C# program that operate as deck dealer on 40 cards deck (following the Fisher Yates shuffeling algorithm https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle). The fun part is that i have…
Skary
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Are there on-line ways to use a block cipher to generate unique $n$ bits that guarantee collision-freeness for $2^n$ times?

$n$ is a run-time variable chosen each time the user runs the implementation. One way I can think is to use any block cipher, say AES, as a seeded CSPRNG to randomly shuffle list of numbers $0, 1, \ldots, 2^n-1$. This way I guarantee…
caveman
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Multiple attributes under shuffled differential privacy

Notation: eps_c (epsilon central), eps_l (epsilon local), n (number of users), d (number of attributes). A single attribute A_i may have |A_i|=r different values for i in [1,d]. Let's suppose each user holds d discrete attributes (e.g., A_1 = Gender…
hharcolezi
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Can you find the consecutive integer from the shuffled bits of the next n integers

Lets say I have $n+1$ integers $x, x+1, x+2, ..., x+n$ which are unsigned. If I apply a hidden permutation $\sigma$ to the bits (right to left) of each respective number I have $x_0', x_1', x_2'$. ($x=\sum_{i} b_i * 2^i, x_0'=\sum_{i} b_{\sigma(i)}…
Ben
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How to construct a permutation (shuffle) oblivious pseudorandom function?

We know that OPRF is a two-party protocol, where Alice inputs $X = {x_1, ..., x_n}$, Bob has no input, and after executing the OPRF protocol, Alice gets $F_k(x_i)$, and Bob receives a pseudorandom key $K$. I wonder if it is possible to construct a…
song
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Is this transposition cipher unbreakable?

Given a password as a seed for a Psuedo Random number generator and Fisher Yates Algorithm to shuffle bytes of a string to random places like Hello World to ldWoeHor ll, is it practically and/or theoretically impossible to break such cipher if…
Sprax
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Paillier cryptosystem for verifiable shuffles

I am looking for some algorithm or implementation on Pailler cryptosystem-based verifiable shuffles for mixNet. So far, all the verifiable shuffles and mixNet are available for ElGamal cryptosystems like the Groth method, etc. Does anyone know the…
Nomana
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Confusion about verifiable shuffle of BFV ciphertexts in paper

I'm trying to understand a specific part of the paper "Lattice-Based Proof of Shuffle and Applications to Electronic Voting" by Aranha et al. In the section discussing verifiable shuffles, the authors write: Verifiable shuffles. One application is…
randy
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How to attack the shuffling of correlated numbers?

Suppose I have a function that accepts vector input $x$ and outputs vector $y=f(x)$. I want to protect the output $y$ through shuffling numbers in it. I hope the shuffling can confuse the attacker by hiding the position information. The ability of…
Hobbit
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