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：一种基于编码理论的单服务器私密信息检索协议被提出。该协议针对线性代数攻击提供计算安全性，解决了以往基于编码理论的私密信息检索方案的主要缺陷。该方法采用两种不同类型的编码，分别基于不同环：一种内部非自由线性码，用于区分添加到查询矩阵中的某些元素；一种外部码，用于生成查询矩阵。此外，若内部码所选基环为$\mathbb Z_m$，协议在服务器端及恢复阶段仅使用模运算。