为解决电子合同在存储、共享过程中出现的数据被篡改或泄露等问题，提出了一种基于区块链的电子合同共享方案。首先，将智能合约与代理重加密技术相结合，构造出一个代理智能合约来代替传统代理重加密过程中的代理商，去中心化地实现了电子合同的安全共享。其次，利用星际文件系统（inter planetary file system,IPFS）存储电子合同密文，区块链存储电子合同索引地址，有效缓解了区块链的存储压力。最后，从方案对比、安全性等方面对所提方案进行分析。
In order to solve the problems of data tampering or leakage in the storage and sharing of electronic contracts, an electronic contract sharing scheme based on blockchain is proposed. First, a proxy smart contract is constructed by combining the contract with the proxy re-encryption to replace the traditional proxy, and the secure sharing of electronic contract is decentralized. Inter planetary file system (IPFS) is then used to store the ciphertext of electronic contract, and the electronic contract index address is stored in the blockchain, which effectively alleviates the storage pressure of the blockchain. Finally, the security performance of the proposed scheme is analyzed.
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