Cryptocurrencies have received a lot of research attention in recent years following the release of the first cryptocurrency Bitcoin. With the rise in cryptocurrency transactions, the need for smart contracts has also increased. Smart contracts, in a nutshell, are digitally executed contracts wherein some parties execute a common goal. The main problem with most of the current smart contracts is that there is no privacy for a party's input to the contract from either the blockchain or the other parties. Our research builds on the Hawk project that provides transaction privacy along with support for smart contracts. However, Hawk relies on a special trusted party known as a manager, which must be trusted not to leak each party's input to the smart contract. In this paper, we present a practical private smart contract protocol that replaces the manager with an MPC protocol such that the function to be executed by the MPC protocol is relatively lightweight, involving little overhead added to the smart contract function, and uses practical sigma protocols and homomorphic commitments to prove to the blockchain that the sum of the incoming balances to the smart contract matches the sum of the outgoing balances.
翻译:随着第一个加密货币比特币交易的增加,智能合同的需求也有所增加。 智能合同是数字执行的合同,有些当事方执行了一个共同目标。目前大多数智能合同的主要问题是,当事方对合同的投入没有隐私,无论是从链条还是从其他当事方。我们的研究建立在提供交易隐私和支持智能合同的霍克项目之上。然而,霍克依赖一个特别受信任的一方,即一个被称为经理的人,不能相信它会泄露每个当事方对智能合同的投入。在本文件中,我们提出了一个实用的私人智能合同协议,用MPC协议取代经理,即由MPC协议执行的功能相对轻,涉及智能合同功能的微小的间接费用,并使用实用的西格玛协议和同质承诺来证明智能合同的余额与到期余额的金额相匹配。