On the Existence of Extractable One-Way Functions
نویسنده
چکیده
Extractability is one of the main and central tools for design and analysis of modern cryptographic protocols. We say a function is extractable if any adversary that outputs a point in the range of the function is guaranteed to ”know” a corresponding preimage. This research presents a short report on the existence of extractable one-way functions based on a recent paper by Bitansky et al. [BCPR16]. We discuss with details on two main results of the paper which: 1) shows that if there exist indistinguishability obfuscators for a certain class of circuits, then there do not exist (generalized) extractable one-way functions, with respect to common auxiliary-input of unbounded polynomial length. 2) presents a contraction of bounded-auxiliary-input extractable one-way functions and bounded-auxiliary-input generalized extractable one-way functions based on relatively standard assumptions (e.g., sub-exponential hardness of Learning with Errors). Finally, we conclude the report.
منابع مشابه
Towards a Theory of Extractable Functions
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