Paper 2019/487

From Single-Input to Multi-Client Inner-Product Functional Encryption

Michel Abdalla, Fabrice Benhamouda, and Romain Gay

Abstract

We present a new generic construction of multi-client functional encryption (MCFE) for inner products from single-input functional inner-product encryption and standard pseudorandom functions. In spite of its simplicity, the new construction supports labels, achieves security in the standard model under adaptive corruptions, and can be instantiated from the plain DDH, LWE, and Paillier assumptions. Prior to our work, the only known constructions required discrete-log-based assumptions and the random-oracle model. Since our new scheme is not compatible with the compiler from Abdalla et al. (PKC 2019) that decentralizes the generation of the functional decryption keys, we also show how to modify the latter transformation to obtain a decentralized version of our scheme with similar features.

Note: update on Section5: Decentralized Multi-Client Functional Encryption

Metadata
Available format(s)
PDF
Category
Cryptographic protocols
Publication info
A minor revision of an IACR publication in ASIACRYPT 2019
Keywords
Decentralizedmulti-client functional encryptioninner products
Contact author(s)
romain rgay @ gmail com
michel abdalla @ ens fr
fabrice benhamouda @ normalesup org
History
2020-02-16: revised
2019-05-19: received
See all versions
Short URL
https://ia.cr/2019/487
License
Creative Commons Attribution
CC BY

BibTeX

@misc{cryptoeprint:2019/487,
      author = {Michel Abdalla and Fabrice Benhamouda and Romain Gay},
      title = {From Single-Input to Multi-Client Inner-Product Functional Encryption},
      howpublished = {Cryptology ePrint Archive, Paper 2019/487},
      year = {2019},
      note = {\url{https://eprint.iacr.org/2019/487}},
      url = {https://eprint.iacr.org/2019/487}
}
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