A digital signature scheme based on the discrete logarithm problem, published by Taher ElGamal in 1984. Not to be confused with the ElGamal encryption system.
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Safe generator for ElGamal signature
What are the properties a generator $g$ should have to be secure for ElGamal signatures (original scheme)?
I am aware that it is poorly chosen and not secure when $g|p-1$ or $g^{-1}|p-1$, where $p$ ...
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Why do we need to hash both the message and the $h$ value in ElGamal signature?
The professor left us a question on ElGamal signatures:
Given the hash function $H$ and message $M$, choose a random $r$ and compute $h=g^r$ and $H(M||h)$. Show that, if $H(M)$ is used instead of ...
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ElGamal signature: Forging a signature of a specific form
I have a question I can't solve from one of the courses I'm currently taking:
Show that given a legitimate ElGamal signature $(S,R)$ on a given message $m$, an attacker
can compute a signature ...
