A Private Information Retrieval (PIR) protocol based on coding theory for a single server is proposed. It provides computational security against linear algebra attacks, addressing the main drawback of previous PIR proposals based on coding theory. The approach involves two types of codes each one over a different ring, an inner non-free linear code that will be used as a distinguisher of some elements added to the query matrix, and an outer code that will be used for generating the query matrix. Moreover, it only uses modular arithmetic at the server level and the recovering stage if the base ring chosen for the inner code is $\mathbb Z_m$.

翻译：提出了一种基于编码理论、适用于单服务器的私密信息检索（Private Information Retrieval，PIR）协议。该协议能抵御线性代数攻击，从而解决了以往基于编码理论的PIR方案的主要缺陷。该方法涉及两类分别定义在不同环上的码：一个用作区分器、用于识别添加到查询矩阵中某些元素的内层非自由线性码，以及一个用于生成查询矩阵的外层码。此外，若内层码所选的基环为$\mathbb Z_m$，则在服务器端及恢复阶段仅需使用模算术运算。