In a blind signature scheme, the signer does not know what he is signing. This is an important building block of anonymous voting or digital cash schemes, because it allows an authority to control the creating of signed messages, but doesn't allow it to track their use.

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Sequence of Encrypting RSA like Chaum Blinding scheme

I'd be a noob in cryptography but reading up a little on RSA, I do get some understanding and I want to specifically resolve this issue. UPDATED Lets say we have the following values in place: ...
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Going Blind, Group or Ring?

I have several problems approaching the following problem: Let's assume that we have Alice, Bob and Cathy. Alice wants to present a message to Cathy, showing her that someone else has signed it (Bob), ...
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Usability of padding scheme in blinded RSA signature?

In Wikipedia's article on Blind signature, in the section Dangers of blind signing which describes RSA blinding attack one reads the following This attack works because in this blind signature ...
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Unblind a RSA blinded signature

I have blinded m = 16 with r= 13, e = 7 and n = 209. This resulted in m' = 464, which led to a s' = 8. Now, I want to unblind this s' by using s = s' * r$^{-1}$ but im stuck at filling in the ...
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Blinding twice in RSA

I understand that if you have a message $m$, you can blind it by selecting a random $r$ and then multiplying $r^e\times m \pmod{n}$ Someone else then signs it with $d$, raising to the power of $d$: ...
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Blind Signatures

The verification algorithm given in blind signature. Should it work for both Original message and the signature on it Blinded message and the signature on it. If yes, then how can we verify if ...
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blinding a hash vs. sending the hash directly

So with blind signatures you have two parties - A and B. A has a message that they want B to sign so A creates a hash of their message, blinds it, and then sends it to B to sign. That, as I understand ...
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PKCS1 and blind RSA signatures

Wikipedia's article on RSA blind signatures says that you need to raise the message $m$ to the secret exponent $d$ modulo the public modulus $N$. Implicit within that, it seems to me, is that m needs ...
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What is “Blinding” used for in cryptography?

What does "blinding" mean in cryptography, and where do we usually use it? Can you describe a sample implementation?
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RSA blind signatures in practice

Hi I have a problem with moving my blind signature implementation from educational (textbook RSA) to more practical (padded RSA) side. David Chaums paper gives a following figure: $r$ - blinding ...
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One-way hash on encrypted data, result hidden from hasher

I'm looking for a one-way hash function that can be performed by A on an encrypted piece of data E(D) provided by B, without the performer A able to figure out D or H(D). This similar to HMAC(Message, ...
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Which blind signature schemes exist, and how do they compare?

I'm looking into blind signature schemes for use as digital cash. I have come across blinded RSA, and Lucre(DH based). Are there other schemes available, and how do they compare? I suspect there ...
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Blind signature with openssl

I'm trying to understand (to reproduce in practice) how does blinded tokens work. Currently i'm lacking examples. According to Wiki the blinded signature protocol is the same as ordinary signature ...