Privacy-preserving scalar product (PPSP) protocols are an important building block for secure computation tasks in various applications. Lu et al. (TPDS'13) introduced a PPSP protocol that does not rely on cryptographic assumptions and that is used in a wide range of publications to date. In this comment paper, we show that Lu et al.'s protocol is insecure and should not be used. We describe specific attacks against it and, using impossibility results of Impagliazzo and Rudich (STOC'89), show that it is inherently insecure and cannot be fixed without relying on at least some cryptographic assumptions.

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对“SPOC”中提出的隐私保护标量产品协议的评论

隐私保护标量积 (PPSP) 协议是各种应用程序中安全计算任务的重要构建块。卢等人。(TPDS'13) 引入了一种 PPSP 协议，该协议不依赖于密码学假设，并且迄今为止已在广泛的出版物中使用。在这篇评论文章中，我们表明 Lu 等人的协议是不安全的，不应使用。我们描述了针对它的特定攻击，并使用 Impagliazzo 和 Rudich (STOC'89) 的不可能结果表明它本质上是不安全的，如果不依赖至少一些加密假设就无法修复。