The Internet of Medical Things (IoMT) is crucial in our daily health monitoring and assisting doctors in treatment. However, the existing schemes mainly use cloud servers to solve the storage of large amounts of data generated by smart devices, ignoring the guarantee mechanism of ciphertext integrity, which may result in data being tampered with or replaced in data sharing. To address this issue, we propose a secure data sharing scheme named roxy e-ncryption for ecure ata haring with lockchain in nternet f edical hings (PRE-IoMT). Specifically, we propose a new proxy re-encryption data sharing approach by introducing identity hash during the key generation phase to realize the binding of public key and user identity, thus enhancing the security of data sharing in PRE-IoMT. Moreover, we adopt BlockChain transactions to design a pairing function ciphertext check mechanism, which can effectively prevent the ciphertext stored in the cloud server from being tampered with. We add the user to the accumulator by invoking the BlockChain smart contract to realize the management and fast query of users. Finally, we conduct the performance analysis experiments on the four-stage computation of proxy re-encryption, communication overhead, storage overhead, transmission delay, and the delay of BlockChain transactions, compared with existing schemes, our scheme improves the computation efficiency of encryption, re-encryption, decryption, and re-decryption by about , , , and respectively. The security proof also exhibits that PRE-IoMT can resist IND-ID-CPA.

中文翻译：

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医疗物联网中区块链安全数据共享的代理重加密

医疗物联网（IoMT）对于我们的日常健康监测和协助医生治疗至关重要。然而，现有方案主要利用云服务器来解决智能设备产生的大量数据的存储，忽略了密文完整性的保证机制，可能导致数据共享时数据被篡改或替换。为了解决这个问题，我们提出了一种名为 roxy e-ncryption 的安全数据共享方案，用于互联网医疗铰链中的锁链安全数据共享 (PRE-IoMT)。具体来说，我们提出了一种新的代理重加密数据共享方法，通过在密钥生成阶段引入身份哈希来实现公钥和用户身份的绑定，从而增强PRE-IoMT中数据共享的安全性。而且，我们采用区块链交易设计了配对功能密文校验机制，可以有效防止云服务器中存储的密文被篡改。我们通过调用区块链智能合约将用户添加到累加器中，实现用户的管理和快速查询。最后，我们对代理重加密的四阶段计算、通信开销、存储开销、传输延迟以及区块链交易延迟进行了性能分析实验，与现有方案相比，我们的方案提高了加密的计算效率，分别由 、 、 和 进行重新加密、解密和重新解密。安全证明还表明PRE-IoMT可以抵抗IND-ID-CPA。