Questions tagged [proxy-re-encryption]
a type of public-key encryption scheme that allows to transform ciphertexts encrypted under Alice's public key into ciphertexts decryptable by Bob
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Does something like Symmetric reencryption exist?
I'm an amateur so bear with me.
I was thinking about an E2E solution for data-at-rest proxy scenarios (like cloud storage provider) that allows you to issue and revoke users via symmetric keys.
I'm ...
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Can you re-encrypt data without knowing what the data is or using PRE?
I'm currently working on a distributed consensus-based system. I currently give the system a private key through a threshold encryption model, and I want to be able to take some data encrypted with ...
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Proxy Re-Encryption based on standard ElGamal
ElGamal-based BBS proxy re-encryption is well known, but it works on a variant of ElGamal like ($mg^r$,$g^{xr})$ not standard ElGamal ($g^r$,$mg^{xr}$). After reading the original paper, I found the ...
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Signature delegation without secret keys
Scenario: have an entity A that cannot hold any secret keys. A concrete example would be: an application that needs to be open sourced and cannot be modified. In order to send any signed messages, it ...
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ElGamal-based BBS proxy re-encryption implementation?
are there any available tools/libraries that implement the idea of EIGamal-based proxy re-encryption scheme shown below? Preferably in Golang. Thank you!
Source of this picture: https://www.cs.jhu....
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How proxy re-encryption works - layman perspective
Here is the use case: A uses B's public key to encrypt a message and sent it to B. In later stages, a new member C joins and B would like to let C be able to see this encrypted message (i.e., give the ...
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Data Security and Encryption
I have a research paper on data security using proxy re-encryption, and I need to provide an answer to a reviewer's comment. However, I have no idea on what to do or how to answer it.
The security ...
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Can RSA re-encrypt a message without decrypting it?
The goal of this question is to allow a server/proxy to forward an encrypted message without being able to read it with this procedure being transparent to the original sender and receiver.
Assume we ...
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How can I use two different public keys with the same private key for fully homomorphic encryption?
I am pretty new to cryptography.
Recently I run into this question where I have two different public keys with the same private key, and I need them for fully homomorphic encryption.
Let's say ...
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DES decryption of the homomorphic encryption ciphertext
I implemented an application using partial homomorphic encryption for outsourced computations. To get an efficient bandwidth, I am thinking to apply (DES) symmetric algorithm to encrypt the message ...
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Collusion resistance in proxy re-encryption scheme depending on bilinear map rules
A proxy re-encryption scheme is collusion resistant, if the proxy and a delegatee are not able to recover the secret key of the delegator. For example, when we have a message that was originally ...
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Multiparty dataset intersection count
Typically, Private Set Intersection (PSI) protocols let you learn the subset of items on each party's dataset that are in the intersection. The problem in this case is a relaxation of these kind of ...
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Symmetric proxy re-encryption practical implementations
I want to encrypt some files in a cloud and delegate decryption rights to authorized users. The performance matters for me and I think I should use schemes utilizing symmetric encryption.
Could ...
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How to upgrade encryption version of many large files?
Assume that I operate a user-facing online file syncing service that offers end-to-end encryption of large files, such that files are encrypted client-side first, then uploaded to the server for ...
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Can Paillier ,RSA or any other schemes be used for universal re-encryption like elGamal?
ElGamal, RSA, and Paillier cryptosystem have homomorphic property, and can be used fro re-encryption purposes. I want to use the encryption to re-encrypt ciphertext(as in proxy re-encryption but ...
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How re-encryption can be done through RSA
Both RSA and Elgamal have homomorphic properties. So both can re-encrypt the ciphertext. Re-encryption with Elgamal works as seen here.
How does re-encryption work using RSA?
What modification / ...
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Securely rekey/re-encrypt AES-encrypted file
Suppose I have a big file encrypted using AES (any mode you want) with key kA.
I'd like to give an untrusted proxy a kA->kB "conversion key" so that it re-encodes ...
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Does Proxy re-encryption can re-encrypt large data?
Many resources talk about the benefit of Proxy Re-encryption (PRE) and I also implement my PRE using Elliptic Curve key pair. But after I set up Global parameters, I can encrypt very small data maybe ...
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Why is a proxy needed in proxy re-encryption?
Context
Here's the usual proxy re-encryption scenario:
Alice, with key pair $(pk_a, sk_a)$ encrypts a message $m$, producing $c = encrypt(pk_a, m)$
Alice saves $c$ on an untrusted storge provider (...
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Is it possible to delegate re-encryption key generation?
In a non-interactive proxy re-encryption scheme, Alice, with the key pair $(pk_a, sk_a)$, needs to issue a re-encryption key $re_{a\rightarrow b}$ once she wants to share her secret message with Bob, ...
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Application of uni-directional proxy re-encryption?
What kinds of applications is uni-directional proxy re-encryption applicable to?
I learned some applications that proxy re-encryption can be used, which are email and file sharing scenarios.
All of ...
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Possible to split a secret to generate a re-encryption key (PRE)?
I am wondering, if it is possible to split a secret (s.th. like shamir's secret sharing) which can be used to generate a re-encryption key in proxy re-encryption and only serve the splitted portions ...
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Proxy Reencryption - semi-trust into proxy required?
As far as I understood, PRE claims to hide the underlying message from being read by the proxy. Why can't the proxy simple use a public key of himself as target?
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Additive homomorphic secret sharing
I am new to cryptography esp, homomorphic encryption. I would like to know if the following is possible using something similiar to additive homomorphic secret sharing. Please apologize me if its too ...
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Is there a proxy re-encryption algorithm for Elliptic Curve ECIES?
I was wondering if there is a way to perform proxy re-encryption for ECIES public-key encryption (i.e. given a message encrypted with Alice's public key, re-encrypt it using Bob's public key). Is that ...
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What's the difference between single key-pair public key encryption and proxy re-encryption?
Proxy Re-Encryption provides the ability to transform a ciphertext encrypted under some key to the one under another key.
This seems interesting. But, something seems strange.
Suppose Alice has a key ...
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Proxy Re-Encryption with provable re-encryption target
Suppose Alice has encrypted some plaintext $P$ to Bob. Bob wishes to re-encrypt this information to Charlie via proxy, in such a manner that:
The proxy cannot obtain $P$
The proxy can prove that Bob ...
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How useful is proxy re-encryption if we end up needing a symmetric key?
I'm trying to design a system using proxy re-encryption (PRE) to allow the sharing of data between a user (delegator) and other users he delegates access to (delegatees). The goal is to use a PRE ...
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Usage of pairings in proxy re-encryption algorithm
I am having trouble understanding one part of the AFGH algorithm for proxy re-encryption (my background in discrete mathematics is lacking a bit).
The paper describes the algorithm setup the ...
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ElGamal proxy re-encryption
I wrote an algorithm to implement a suggestion in a paper by Ivan and Dodis to convert a regular ElGamal encryption scheme into a proxy re-encryption one (it's at page 6, left column of this but I ...
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Identity-based proxy re-encryption using different system parameters
I am wondering if there is an identity based proxy re-encryption scheme (such as the Green-Ateniese scheme https://eprint.iacr.org/2006/473.pdf) that converts an encryption computed with ID1, system ...
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Proxy re-encryption mod operations
I managed to implement the proxy re-encryption scheme from http://eprint.iacr.org/2009/189.pdf in Python 2.7, however I am having performance issues. As it is, I can run the algorithm for key sizes up ...
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What scheme will allow merging and splitting the result of a function?
I am wondering if it's possible to have a scheme as follows.
Here is the scenario:
we have a set of objects (e.g. strings) {O1, O2, ..., On}
we have a set of users {U1, U2, ..., Um}
each user asks ...
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Is there an encyption scheme that combines additive homomorphism with ability to proxy re-encrypt?
Is there an encyption scheme that combines additive homomorphism with ability to proxy re-encrypt? I've tried digging around on the Internet but haven't found anything conclusive on the topic.
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Can we proxy-re-encrypt using homomorphic encryption schemes?
Homomorphic encryption schemes are PKE schemes with an additional special method Evaluate.
The Evaluate method takes input any function (as boolean circuit) and encrypted inputs of the function and ...
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How practical is proxy re-encryption for AES?
In proxy re-encryption schemes, a proxy is given special information that allows it
to translate a ciphertext under one key into a ciphertext of the same message under a
different key.
How ...
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