从TS-SUF-2到TS-SUF-4：FROST2阈值签名的实用安全增强

中文摘要 AI 辅助

阈值签名方案在保护区块链和分布式系统内的数字资产方面发挥着至关重要的作用。FROST2作为一种实用的阈值Schnorr签名方案脱颖而出，以其高效性和与标准验证流程的兼容性而著称。然而，在一次性离散对数假设下，在静态腐败和集中式密钥生成设置中，Bellare等人（CRYPTO 2022）已证明FROST2仅能达到TS-SUF-2安全性，这是其易受TS-UF-3攻击的结果。在本文中，我们通过提出FROST2的增强变体FROST2+来解决这一安全限制，该变体在与原始FROST2相同的计算假设下达到TS-SUF-4安全级别。FROST2+通过集成额外的预处理令牌验证来增强FROST2，这有助于缓解TS-UF-3和TS-UF-4漏洞，同时保持实际效率。我们证明，FROST2+不仅能在与原始FROST2分析相同的条件下实现TS-SUF-4安全性，而且在初始化时使用诸如PedPoP之类的分布式密钥生成协议也能实现该安全性。我们使用ZCash的FROST库进行的基准测试表明，在启用预计算时，FROST2+的性能与FROST2相当，并且比FROST快约64-79%。

英文摘要

Threshold signature schemes play a vital role in securing digital assets within blockchain and distributed systems. FROST2 stands out as a practical threshold Schnorr signature scheme, noted for its efficiency and compatibility with standard verification processes. However, under the one-more discrete logarithm assumption, with static corruption and centralized key generation settings, FROST2 has been shown by Bellare et al. (in CRYPTO 2022) to achieve only TS-SUF-2 security, which is a consequence of its vulnerability to TS-UF-3 attacks. In this paper, we address this security limitation by presenting an enhanced variant of FROST2, namely, FROST2+ which achieves the TS-SUF-4 security level under the same computational assumptions as the original FROST2. FROST2+ strengthens FROST2 by integrating additional pre-processing token verifications that help mitigate TS-UF-3 and TS-UF-4 vulnerabilities while maintaining practical efficiency. We show that FROST2+ can achieve TS-SUF-4 security not only under the same conditions as the original FROST2 analysis, but also when initialized with a distributed key generation protocol such as PedPoP. Our benchmark using ZCash's FROST library shows that the performance of FROST2+ is comparable to FROST2 and about 64-79% faster than FROST when precomputation is enabled.

发表机构

• Solv Protocol, Singapore（Solv协议）

机构由 AI 辅助整理，请以论文原文为准。