Cryptography Stack Exchange
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Questions tagged [distributed-decryption]

20 questions
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Proof of correct construction of a private key in distributed cryptography

In an exponential ElGamal encryption scheme where the key generation is done in a distributed way among $n$ trustees we have that each trustee $i$ (where $1 \leq i \leq n$): Selects a private key share $x_i \in \mathbb{Z}_q^{\star}$. Computes a…
LRM
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Is it possible to decrypt only a portion of a gpg encrypted file?

I have very large encrypted files that I need to process in a highly parallel fashion (the files are composed of distinct records of data). Currently, the process begins by first decrypting the data, then starting the parallel work with each worker…
James Maroney
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How to generate Multiple Encryption Keys for use in RSA polymorphic multiplication

I am a long time scroller, first time poster in the crypto stack. I've recently been finding myself leaving the realm of mainstream/standard crypto (imo that consists of symmetric/asymmetric encryption, some ciphers and one way hash functions ect).…
Dimitree
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A method for creating distributed public key for ECDSA, what are the risk factors?

There is quite a bit of literature on distributed ECC signing without a trusted dealer. Published works are mostly overly complicated, so I am proposing this simple technique which I am sure if it is valid is already published (but I couldn't find…
naiem
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Encryption in a Distributed PKI?

Given a PKI infrastructure with a root node that signs CSR's for nodes Alice, Bob, and Carol. Is it possible for Alice to encrypt some information, store it publicly somewhere, then later Bob or Carol can decrypt that information, without Alice,…
Uncle Spook
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Dynamic Distributed Key Generation for elGamal

I am looking for a scheme for dynamic threshold public-key encryption, which includes dynamic distributed key generation. Namely, the number of parties that participate in DKG is bounded, but unknown. The list of public keys of each party is known,…
Stanislaw Baranski
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Distributed Asymmetric Key Decryption with threshold

Threshold decryption of public-key encryption schemes allows the decryption key to be distributed among trustees. Then, to decrypt the ciphertext it requires at least threshold t trustees to run the decryption protocol in order to get the plain…
sashank
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Distributed key generation when all parties need to participate

Suppose $n$ parties where $t$ are honest want to perform a distributed key generation protocol. There are many existing schemes. In the simpler setting where all $n$ parties must be online, otherwise the protocol aborts, does the following…
lamba
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Question on double-asymmetric encryption and split knowledge

Moin moin, Let‘s assume there are two keypairs (d1,e1) and (d2,e2), where d1 and d2 are unrelated private keys and e1 and e2 the corresponding public keys. Imagine Alice knowing neither d1 nor d2 and Bob only d1, not d2. Alice has a ciphertext c…
Charly
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Dining-Cryptographer Net (DC-Net) Scheme that Handles Collisions?

[Question edited at the request of Mods] I recently became fascinated with the elegant and simple solution that Chaum proposed for the Dining Cryptographers problem. If you are unfamiliar, please checkout Wikipedia for a summary and solution. What…
A M
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Decentralized / Distributed Private Key Generation between Untrusted Parties?

I found an interesting concept in this paper, page 13, (Link to the paper) called "Decentralized private key generation", as follows: "Decentralized private key generation – Multiple Enigma nodes locally create a segment of the key, whereas the…
Questioner
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Is encrypting a secret key and being able to decrypt plain text with it possible?

Please forgive me if this is a basic question, I'm in high school so I still don't understand very much. Let's say there are two servers, each with a set of public and private keys. These denote server one: $PK^1, SK^1$ and server two: $PK^2, SK^2$.…
kleenex
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RSA decrypting of a huge file by parts

I need to decrypt a huge file that I own previously encoded by myself with a RSA public key (it's possible for this step using a symmetric algorithm key). Problem is that I can't load it in my disposable memory for specific embedded architecture…
Alex
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Decrypt AES-128 with key file but missing IV?

I want to decrypt a file that has been encrypted using AES-128 in CBC mode using OpenSSL. I got the “.key” file – which is 32 digits – but when I try to decrypt with OpenSSL, the program asks me for “-iv” and I don't know the IV of that file so it…
BelindaSchull
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Multi-party decryption, no central decrypter

Recently a bank had a costly mistake that resulted in their master private key being exposed. Through this thread, I learned about multi-party key storage with Adi Shamir's secret sharing scheme as the basis, very cool. In the naive setup, there's…
nitsujri
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