Improved Self-certified Partially Blind Signature Scheme

Ijca Proceedings on International Conference on Emergent Trends in Computing and Communication, 2014

Internet has become an Integral part and prime need of every human being in their day to day life. People now prefer to do transaction over the internet than doing it offline as it reduces time consumption. In such scenarios, securing customer data is one of the biggest challenges for software developers. For this reason Security protocols like Blind Signature Scheme came into picture where requester is allowed obtain a signature from the signer who signs a message without reading the content of the message, and cannot link the protocol with the resulting message signature pair. Blind Signature scheme is mostly used for E-commerce applications like Digital payment system, Electronic-voting system as it provides security goals like blindness, untraceability, correctness and nonforgeability. Neal Koblitz and Victor S. Miller has presented Elliptic curve cryptography (ECC) which is an approach to public key cryptography based on algebraic structure of elliptic curves in over finite fields. Elliptic curve cryptosystem is more efficient than other public key cryptosystem due to difficulty in solving elliptic curve discrete logarithm problem. Using the benefits of elliptic curve cryptography we have presented implementation of blind signature scheme using JAVA.

2023

Blind digital signature schemes allow for digital documents to be signed and verified without revealing the contents of the document to the signer. This paper provides a brief introduction to blind digital signatures and surveys several of their uses in data privacy applications, including e-voting, anonymous e-cash, and e-healthcare. For concreteness, RSA-based signatures are considered in some detail.

IACR Cryptol. ePrint Arch., 2017

We propose a novel cryptographic primitive called conditional blind signatures. Our primitive allows a user to request blind signatures on messages of her choice. The signer has a secret Boolean input which determines if the supplied signature is valid or not. The user should not be able to distinguish between valid and invalid signatures. A designated verifier, however, can tell which signatures verify correctly, and is in fact the only entity who can learn the secret input associated with the (unblinded) signed message. We instantiate our primitive as an extension of the Okamoto-Schnorr blind signature scheme and provide variations to fit different usage scenarios. Finally, we analyze and prove the security properties of the new scheme and explore potential applications.

2018

This report will discuss on an idea proposed in a journal which published on 2017, which covered within blind signature protocol domain. In that journal, authors covered the fundamental behind blind signature protocol, history of creation, the challenges on current practices and proposing 3 new algorithms to overcome on current challenges. Original journal accessible at https://pdfs.semanticscholar.org/d3f7/9ff8af49542adb72864981c0fe2a757f28bb.pdf

Journal of Computer Security, 2013

Blind signatures allow users to obtain signatures on messages hidden from the signer; moreover, the signer cannot link the resulting message/signature pair to the signing session. This paper presents blind signature schemes, in which the number of interactions between the user and the signer is minimal and whose blind signatures are short. Our schemes are defined over bilinear groups and are proved secure in the common-reference-string model without random oracles and under standard assumptions: CDH and the decision-linear assumption. (We also give variants over asymmetric groups based on similar assumptions.) The blind signatures are Waters signatures, which consist of 2 group elements. Moreover, we instantiate partially blind signatures, where the message consists of a part hidden from the signer and a commonly known public part, and schemes achieving perfect blindness. We propose new variants of blind signatures, such as signer-friendly partially blind signatures, where the public part can be chosen by the signer without prior agreement, 3-party blind signatures, as well as blind signatures on multiple aggregated messages provided by independent sources. We also extend Waters signatures to non-binary alphabets by proving a new result on the underlying hash function.

Blind signature allows a requester to obtain signature from a signer on any document in such a way that, the authority learns nothing about the message that is being signed. Due to the blindness and untraceability properties of Blind Signature Scheme, it can be used in cryptographic applications such as web based e-voting, digital cash etc. In this paper, a novel blind signature scheme based on Elliptic Curve Discrete Logarithm Problem has been proposed. The model has been explained using a customer-and-bank example and the proof of correctness has been made.

partially blind signature is a variant of the blind signature. The partially blind signature scheme allows a signer to sign a partially blind message that explicitly includes the pre-agreed information. In 2005, Chow et al. first proposed an ID-based partially blind signature scheme with bilinear pairings. ID-based public key systems with bilinear pairings defined on elliptic curves offer a flexible approach to achieve both simplifying the certificate management and reducing the computational cost. However, their scheme is time-consuming for requesters (or clients) with mobile devices. In 2007, Hu and Huang proposed an efficient ID-based partially blind signature scheme based on bilinear pairings. They claimed that the proposed scheme is provably secure under the random oracle model. However, this paper shows that the Hu-Huang scheme suffers from forgery attacks.

This paper presents a new partially blind signature, dedicated for sensitive applications, and depending on agreement factors. In the traditional partially blind signature schemes, there is an agreement between the sender and the signer, but in this method, the agreement is used to recover blind messages by an individual group of users and to enforce the system's security.The blind signature used in this method is based on RSA scheme designed by Chaum [1] as an initial step to our system with modifications. The proposed method enhances the important properties of blind signature schemes such as unforgeability, the anonymity, blindness and others. The security of this developed system is analyzed to show the importance of agreement in blind signatures. The most important property of this scheme is to classify messages according to their sensitivity that can be used to recover unblined message by authentication group selected by the singer and to use agreement secure information to get more secure system.

2021

Blind signatures provide authenticity, integrity, nonrepudiation, blindness and untraceability of the message contents. In blind signature, the signer signs the message without revealing the contents of a message. Certificateless blind signature scheme is the combination of certificateless scheme and blind signature scheme. In certificateless blind signature scheme there is no need of certificates to verify the authenticity of the public key of user. In this research, the “Certificatrless blind signature scheme using ECC” of Nayak et al is analyzed. The analysis shows that the proposed certificateless blind signature scheme is not secure against the known cryptanalysis attacks. In fact, an attacker can easily reveal the secret key of the signer by mounting a forgery attack and can become a fake signer. After a successful cryptanalysis, a modified version of the scheme is presented. In the modified version of the scheme, the elliptic curve encryption and decryption is introduced in t...

Journal of Mathematics and Statistics, 2008

Partially blind signatures played an important role in many electronic commerce applications. Many existing partially blind signature scheme based on a single hard problem but not secure. In this study, we propose a secure partially blind signature scheme based on factoring and discrete logarithms and show that the proposed scheme satisfies the partial blindness, randomization, unlinkability and unforgeability properties. We also analyse the computation cost of the proposed scheme.