Completeness Theorems for Adaptively Secure Broadcast
Completeness Theorems for Adaptively Secure Broadcast
复制标题
自适应安全广播的完备性定理
DOI：
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复制
发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Vassilis Zikas
中科院分区：
文献类型：
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作者：
Ran Cohen;J. Garay;Vassilis Zikas
区块链协议的出现重新点燃了人们对自适应安全广播的兴趣，因为现在人们已经很清楚，通过扩散网络进行广播允许自适应攻击者根据其试图发送和更改的消息破坏发送方。Hirt和Zikas [Eurocrypt ' 10]证明，在基于模拟的环境中，这是广播的固有局限性，也就是说，面对一个自适应的对手，这个任务是不可能的。本文的贡献是双重的。首先，我们在基于属性和基于模拟的设置中设计了自适应安全广播的完整特征，并假设了各种常见设置。我们的调查表明，与之前的看法相反，自适应安全广播的上述限制不是基于模拟的安全的工件，而是自适应安全的固有问题。特别是，我们表明：(1)它也适用于自适应对手的基于属性的广播定义，并且(2)与自适应安全中的其他不可能性不同，这种不可能性不能通过添加可编程随机oracle来规避。其次，我们转向资源限制密码学（RRC）范式[Garay et al., Eurocrypt ' 20]，该范式被证明在规避不可能结果方面很有用，并询问它是否也影响上述负面结果。我们肯定地回答了这个问题，证明了时间锁谜题（TLPs）——可以看作rrc的一个实例——确实允许实现基于属性的定义，并规避了自适应安全广播的不可能性。那么自然的问题是，TLPs是否也允许基于模拟的自适应安全广播，以防止损坏的多数？我们的回答是否定的。尽管如此，我们表明可以通过可编程随机-oracle模型中TLPs的非提交模拟来实现积极的结果。作为第一
The advent of blockchain protocols has reignited the interest in adaptively secure broadcast, as it is by now well understood that broadcasting over a diffusion network allows an adaptive adversary to corrupt the sender depending on the message it attempts to send and change it. Hirt and Zikas [Eurocrypt ’10] proved that this is an inherent limitation of broadcast in the simulation-based setting, i.e., that this task is impossible against an adaptive adversary corrupting a strict majority of the parties. The contributions of this paper are two-fold. First, we devise a complete characterization of adaptively secure broadcast both in the property-based and in the simulation-based setting, and assuming a wide class of common setups. Our investigation reveals that, contrary to previous perception, the above limitation of adaptively secure broadcast is not an artifact of simulation-based security, but rather an inherent issue of adaptive security. In particular, we show that: (1) it also applies to the property-based broadcast definition adapted for adaptive adversaries, and (2) unlike other impossibilities in adaptive security this impossibility cannot be circumvented by adding a programmable random oracle. Second, we turn to the resource-restricted cryptography (RRC) paradigm [Garay et al. , Eurocrypt ’20], which was proven useful in circumventing impossibility results, and ask whether it also affects the above negative result. We answer this question in the affirmative, by showing that time-lock puzzles (TLPs)—which can be viewed as an instance of RRC—indeed allow for achieving the property-based definition and circumvent the impossibility of adaptively secure broadcast. The natural question is then, do TLPs also allow for simulation-based adaptively secure broadcast against corrupted majorities? We answer this in the negative. Nonetheless, we show that a positive result can be achieved via a non-committing analogue of TLPs in the programmable random-oracle model. As first
不可延展的时间锁谜题和应用
DOI：
10.1007/978-3-030-90456-2_15
发表时间：
2021
期刊：
TCC'21
影响因子：
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作者：
Cody Freitag;Ilan Komargodski;Rafael Pass;Naomi Sirkin
通讯作者：
Naomi Sirkin
同态时间锁谜题及其应用
DOI：
10.1007/978-3-030-26948-7_22
发表时间：
2019
期刊：
影响因子：
--
作者：
Giulio Malavolta;Sri Aravinda Krishnan Thyagarajan
通讯作者：
Sri Aravinda Krishnan Thyagarajan
影响因子：
2.5
作者：
Canetti, Ran
通讯作者：
Canetti, Ran