Partially blind signature schemes are an extension of blind signature schemes that allow a signer to explicitly include necessary information (expiration date, collateral conditions, or whatever) in the resulting signatures under some agreement with the receiver. This paper formalizes such a notion and presents secure and efficient schemes based on a widely applicable method of obtaining witnes...

A seminal result in cryptography is that signature schemes can be constructed (in a black-box fashion) from any one-way function. The minimal assumptions needed to construct blind signature schemes, however, have remained unclear. Here, we rule out black-box constructions of blind signature schemes from one-way functions. In fact, we rule out constructions even from a random permutation oracle,...

Cryptography based on the theory of error correcting codes and lattices has received a wide attention in the last years. Shor’s algorithm showed that in a world where quantum computers are assumed to exist, number theoretic cryptosystems are insecure. Therefore, it is important to design suitable, provably secure post-quantum signature schemes. Code-based public key cryptography has the charact...

In this article, we show that the Chien et al. s partially blind signature scheme based on RSA public cryptosystem could not meet the untraceability property of a blind signature. 2002 Elsevier Inc. All rights reserved.

Abstract A (t, n) threshold proxy signature scheme enables an original signer to delegate the signature authority to a proxy group of n member such that t or more than t proxy signers can cooperatively sign messages on behalf of the original signer. In the paper, we review the security of some nonrepudiable threshold proxy signature schemes with known signers. We show that Sun’s threshold proxy...

Abstract: This paper constructs a new group blind signature scheme on the basis of CZK group signature scheme. The security of the new scheme is under the computational Diffie-Hellman problem in the random oracle model. In our scheme, to blind the group signature of CZK only adds the computation of modular addition; while the scheme in LR98 adds the computation of double discreet logarithm, roo...

We present the design and implementation of Sensus, a practical, secure and private system for polling (conducting surveys and elections) over computer networks. Expanding on the work of Fujioka, Okamoto, and Ohta, Sensus uses blind signatures to ensure that only registered voters can vote and that each registered voter only votes once, while at the same time maintaining voters’ privacy. Sensus...

Blindness and unforgeability are two essential security requirements of a secure blind signature scheme. Blindness means that after interacting with various users, the signer can never be able to link a valid message pair. Blindness is meaningless if after interacting with various users, the signer is able to link a valid message signature pair. This security vulnerability is known as linkabili...

Cryptography is increasingly applied to the E-commerce world, especially to the untraceable payment system and the electronic voting system. Protocols for these systems strongly require the anonymous digital signature property, and thus a blind signature strategy is the answer to it. Chaum stated that every blind signature protocol should hold two fundamental properties, blindness and intractab...

Proxy blind signature, which combines the properties of both proxy signature and blind signature, is useful in e-cash and e-commerce. In this paper, we present a verifiable self-certified public key scheme and a proxy blind signature scheme using the verifiable self-certified public key. The self-certified public key has an advantage which can withstand public key substitution attacks. As far a...