Questions tagged [fiat-shamir]

The Fiat–Shamir heuristic takes an interactive proof of knowledge and uses this as base to create a digital signature.

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Weak Challenge Generation - Fiat-Shamir Heuristic

The Fiat-Shamir heuristic may be applied to transform a Sigma-Protocol on R(x,w) into a ZKPoK. Let's call the prover's first message ...
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Could be El-Gamal signature scheme constructed via Fiat-Shamir heuristic?

For example, Schnorr signature is pretty similar to El-Gamal. And everywhere where Schnorr signature is explained (for example - on Wikipedia), there's said that there's Schnorr scheme which is ...
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Challenges of Fiat-Shamir Transformation of ZK Proof / Sigma Protocol

Let $\Sigma$ be a sigma protocol whose commitment, challenge and response phases are $\Sigma_1, \Sigma_2, \Sigma_3$, respectively. In Fiat-Shamir Transformation, the challenges are $H(\Sigma_1)$ ...
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Sigma Protocol with Privacy-preserving Discrete Logarithms?

I've been reading up on Sigma Protocols and Fiat-Shamir Heuristic. There is a small problem I see here that is possibly already solved, but I'd like to know if it has a solution. Peggy wants to prove ...
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Need tips on how to break Fiat-Shamir sigma-protocol (programming challenge)

I'm completely stuck on an university programming challenge and I need some tips to get me out of the valley I'm in, you don't need to give the full answer if you do not wish to. What we have: Fiat ...
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Valid reencryption of simple mixnet

How can I provide a non interactive proof using the Fiat Shamir method for the valid reencryption of a simple mixnet?
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168 views

Fiat Shamir with S^3

I'm trying to do Fiat Shamir but with $I = S^3 \pmod n$ where $S$ is the secret key. How will I prove that I know the cube root? I tried doing the old formula but with instead with $(RS)^3 = x*I \pmod ...
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Zero Knowledge Non Interactive Proof with random oracle

I am trying to write an assay about Non Interactive Zero-Knowledge proofs and would like to take the simple discrete logarithm problem example fallowing the Feige-Fiat-Shamir heuristics. I understand ...