Unclonable Encryption in the Haar Random Oracle Model

Abstract:We construct unclonable encryption (UE) in the Haar random oracle model, where all parties have query access to $U,U^\dagger,U^*,U^T$ for a Haar random unitary $U$. Our scheme satisfies the standard notion of unclonable indistinguishability security, supports reuse of the secret key, and can encrypt arbitrary-length messages. That is, we give the first evidence that (reusable) UE, which requires computational assumptions, exists in "microcrypt", a world where one-way functions may not exist. As one of our central technical contributions, we build on the recently introduced path recording framework to prove a natural ``unitary reprogramming lemma'', which may be of independent interest.

Cryptography and Security (cs.CR); Quantum Physics (quant-ph)

arXiv:2603.11437 [cs.CR]

(or arXiv:2603.11437v2 [cs.CR] for this version)

https://doi.org/10.48550/arXiv.2603.11437 Focus to learn more arXiv-issued DOI via DataCite

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