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arXiv · 1905.05490

Non-malleability for quantum public-key encryption

Christian Majenz·Christian Schaffner·Jeroen van Wier
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Abstract

Non-malleability is an important security property for public-key encryption (PKE). Its significance is due to the fundamental unachievability of integrity and authenticity guarantees in this setting, rendering it the strongest integrity-like property achievable using only PKE, without digital signatures. In this work, we generalize this notion to the setting of quantum public-key encryption. Overcoming the notorious "recording barrier" known from generalizing other integrity-like security notions to quantum encryption, we generalize one of the equivalent classical definitions, comparison-based non-malleability, and show how it can be fulfilled. In addition, we explore one-time non-malleability notions for symmetric-key encryption from the literature by defining plaintext and ciphertext variants and by characterizing their relation.

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Christian Majenz, Christian Schaffner, Jeroen van Wier. 2019-05-14. Non-malleability for quantum public-key encryption. https://arxiv.org/abs/1905.05490

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