Searchable encryption is an effective way to ensure the security and availability of encrypted outsourced cloud data. Among existing solutions, the keyword exact search solution is relatively inflexible, while the fuzzy keyword search solution either has a high index overhead or suffers from the false-positive. Furthermore, no existing fuzzy keyword search solution considers the homoglyph search on encrypted data. In this paper, we propose an efficient privacy-preserving homoglyph search scheme supporting arbitrary languages (POSA, in short). We enhance the performance of the fuzzy keyword search in three aspects. Firstly, we formulate the similarity of homoglyph and propose a privacy-preserving homoglyph search. Secondly, we put forward an index build mechanism without the false-positive, which reduces the storage overhead of the index and is suitable for arbitrary languages. Thirdly, POSA returns just the user’s search, i.e., all returned documents contain the search keyword or its homoglyph. The theoretical analysis and experimental evaluations on real-world datasets demonstrate the effectiveness and efficiency of POSA.

可搜索加密是确保加密外包云数据安全性和可用性的有效方式。在现有的解决方案中，关键词精确搜索解决方案相对不灵活，而模糊关键词搜索解决方案要么索引开销高，要么存在误报。此外，现有的模糊关键字搜索解决方案都没有考虑对加密数据的同形字搜索。在本文中，我们提出了一种支持任意语言（简称 POSA）的高效隐私保护同形文字搜索方案。我们从三个方面增强了模糊关键字搜索的性能。首先，我们制定了同形文字的相似度，并提出了一种保护隐私的同形文字搜索。其次，我们提出了一个没有误报的索引构建机制，减少了索引的存储开销，适用于任意语言。第三，POSA 只返回用户的搜索，即所有返回的文档都包含搜索关键字或其同形文字。对真实世界数据集的理论分析和实验评估证明了 POSA 的有效性和效率。