ABSTRACT Recently, a quantum blind signature scheme based on the ‐state for quantum supply chain finance has been proposed, which utilizes blindness to protect the privacy of participating firms. However, our analysis found that this scheme cannot resist the intercept‐measurement‐resend attack and the entanglement‐measurement attack, and the blind operation is ineffective against the insider attacker. Importantly, the blind signer can achieve existential forgery through a valid signature. Then, an improved scheme was proposed that reduces quantum bit consumption, eliminates the need for quantum state swap tests, and extends the message space for signatures to the more universal classical bit space. We have constructed a security model that formally defines the security properties and adversary capabilities of the quantum blind signature. Through this model, the blindness and unforgeability of the improved scheme are reduced to the principles of quantum mechanics in four games. The vulnerabilities of the original scheme and the feasibility of the improved scheme in quantum computing have been verified through the Qiskit simulator.
ABSTRACT Recently, a quantum blind signature scheme based on the ‐state for quantum supply chain finance has been proposed, which utilizes blindness to protect the privacy of participating firms. However, our analysis found that this scheme cannot resist the intercept‐measurement‐resend attack and the entanglement‐measurement attack, and the blind operation is ineffective against the insider attacker. Importantly, the blind signer can achieve existential forgery through a valid signature. Then, an improved scheme was proposed that reduces quantum bit consumption, eliminates the need for quantum state swap tests, and extends the message space for signatures to the more universal classical bit space. We have constructed a security model that formally defines the security properties and adversary capabilities of the quantum blind signature. Through this model, the blindness and unforgeability of the improved scheme are reduced to the principles of quantum mechanics in four games. The vulnerabilities of the original scheme and the feasibility of the improved scheme in quantum computing have been verified through the Qiskit simulator.
The blind signature is widely used in cryptography applications because it can prevent the signer from gaining the original message. Owing to the unconditional security, the quantum blind signature is more advantageous than the classical one. In this paper, we propose a new provable secure quantum blind signature scheme with the nonorthogonal single-photon BB84-state and provide a new method to encode classical messages into quantum signature states. The message owner injects a randomizing factor into the original message and then strips the blind factor from the quantum blind signature signed by the blind signer. The verifier can validate the quantum signature and announce it publicly. At last, the analytical results show that the proposed scheme satisfies all of the security requirements of the blind signature: blindness, unforgeability, non-repudiation, unlinkability, and traceability. Due to there being no use of quantum entanglement states, the total feasibility and practicability of the scheme are obviously better than the previous ones.
ABSTRACT As quantum technology advances, classical digital signatures exhibit vulnerabilities in preserving security properties during the transmission of information. Working toward a reliable communication protocol, we introduce a proxy blind signature scheme to teleport a single particle qubit state with a message to the receiver, employing a three qubit GHZ entangled state. The blindness property is utilized to secure the message information from the proxy signer. A trusted party, Trent, is introduced to supervise the communication process. Alice blinds the original message and sends the Bell measurements with her entangled particle to proxy signer Charlie. After receiving measurements from Alice and Charlie, Bob verifies the proxy blind signature and performs appropriate unitary operations on his particle. Thereafter, Trent verifies the security of the quantum teleportation setup by matching the output data with the original data sent by Alice. Security analysis results prove that the proposed scheme fulfils the basic security necessities, including undeniability, unforgeability, blindness, verifiability, and traceability.
In this paper, we propose a novel semiquantum proxy blind signature scheme using quantum teleportation based on χ states, where the original message owner, proxy signer, and third party are quantum participants with complete quantum capabilities, while the original signer and signature verifier are semiquantum participants with limited quantum capabilities. Our protocol not only has complete blindness, unforgeability, and nonrepudiation, but it also resists the attack behavior of an eavesdropper. Because of the limited quantum capabilities of the original signer and signature verifier, our protocol does not require them to prepare and measure the quantum superposition and quantum entangled states when used in practical applications. Hence, our protocol can reduce the burden of quantum state preparation and measurement for the original signer and signature verifier.
Abstract The authors present a novel token exchange scheme with an example of an electronic cash (eCash) transaction scheme that ensures quantum security, addressing the vulnerabilities of existing models in the face of quantum computing threats. The authors’ comprehensive analysis of various quantum blind signature mechanisms revealed significant shortcomings in their applicability to eCash transactions and their resilience against quantum adversaries. In response, the authors drew inspiration from D. Chaum's original classical eCash scheme and innovated a quantum‐secure transaction framework. The authors detail the developed protocol and rigorously evaluate its security aspects. The protocol's adherence to critical security requirements such as blindness, non‐forgeability, non‐deniability, and prevention of double spending is analysed. Moreover, the scheme against Intercept and Resend, Denial of Service, Man‐in‐the‐Middle, and Entangle‐and‐Measure attacks is rigorously tested. The authors’ findings indicate a robust eCash transaction model capable of withstanding the challenges posed by quantum computing advancements.
The paper uses the uncertainty principle and nocloning theorem; then combines the fundamental properties of quantum mechanics with the cryptographic hash function together; after that proposes a new security quantum blind signature.The analysis of security shows that the improved scheme has the feature of non-forgery, non-disavowal.Compares with other quantum signature, the new scheme needn't to update the signer's transmission private key and it can avoid the signer's private key being exposed by the sender.Moreover, the improved scheme has guiding significance value to further optimal design quantum blind signature and quantum signature, etc.
In order to solve the security of electronic transactions on limited goods, some quantum blind double signature (QBDS) protocols were proposed. In existing QBDS protocols, all participants must have specific quantum computing capabilities. Realistically, high cost of quantum devices may hinder people from using the QBDS protocol. Therefore, we propose a semi-quantum arbitrator blind double signature (SQABDS) scheme. In this scheme, the sender (signer) and the receiver both are classical participants, which can relatively reduce the dependence on quantum hardware. The introduction of blind signers can protect the privacy of electronic transactions, the introduction of semi-trusted arbitrator can relax the strong assumption about the trustworthiness of the arbitrator, for the arbitrator cannot forge the signature. In addition, the SQABDS scheme can be used to sign classical messages directly without performing any quantum swapping tests or quantum gate operations. Finally, the analysis shows that our scheme is securer and its quantum cost is relatively lower.