In recent years, it has become popular to upload patients’ medical data to a third-party cloud server (TCS) for storage through medical Internet of things. It can reduce the local maintenance burden of the medical data and importantly improve accuracy in the medical treatment. As remote TCS cannot be fully trusted, medical data should be encrypted before uploading, to protect patients’ privacy. However, encryption makes search capabilities difficult for patients and doctors. To address this issue, Huang et al. recently put forward the notion of Public-key Authenticated Encryption with Keyword Search (PAEKS) against inside keyword guessing attacks. However, the existing PAEKS schemes rely on time-consuming computation of parings. Moreover, some PAEKS schemes still have security issues in a multiuser setting. In this paper, we propose a new and efficient PAEKS scheme, which uses the idea of Diffie-Hellman key agreement to generate a shared secret key between each sender and receiver. The shared key will be used to encrypt keywords by the sender and to generate search trapdoors by the receiver. We prove that our scheme is semantically secure against inside keyword guessing attacks in a multiuser setting, under the oracle Diffie-Hellman assumption. Experimental results demonstrate that our PAEKS scheme is more efficient than that of previous ones, especially in terms of keyword searching time.

中文翻译：

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云辅助医疗物联网的高效可搜索公钥认证加密

近年来，将患者的医疗数据上传到第三方云服务器（TCS）以便通过医疗物联网进行存储已变得很流行。它可以减轻医疗数据的本地维护负担，并重要地提高医疗的准确性。由于不能完全信任远程TCS，因此在上传之前应对医疗数据进行加密，以保护患者的隐私。但是，加密使患者和医生的搜索功能变得困难。为了解决这个问题，Huang等。最近，针对内部关键字猜测攻击提出了带有关键字搜索的公共密钥身份验证加密（PAEKS）的概念。但是，现有的PAEKS方案依赖于费时的配对计算。此外，某些PAEKS方案在多用户设置中仍然存在安全问题。在本文中，我们提出了一种新的高效PAEKS方案，该方案使用Diffie-Hellman密钥协议的思想在每个发送方和接收方之间生成共享的秘密密钥。共享密钥将由发送方用来加密关键字，并由接收方生成搜索陷门。我们证明，在oracle Diffie-Hellman假设下，该方案在多用户设置下在语义上是安全的，可防止内部关键字猜测攻击。实验结果表明，我们的PAEKS方案比以前的方案更有效，特别是在关键字搜索时间方面。我们证明，在oracle Diffie-Hellman假设下，该方案在多用户设置下在语义上是安全的，可防止内部关键字猜测攻击。实验结果表明，我们的PAEKS方案比以前的方案更有效，特别是在关键字搜索时间方面。我们证明了在oracle Diffie-Hellman假设下，该方案在多用户设置下在语义上是安全的，可防止内部关键字猜测攻击。实验结果表明，我们的PAEKS方案比以前的方案更有效，特别是在关键字搜索时间方面。