---
res:
  bibo_abstract:
  - "Functional encryption (FE) is a primitive where the holder of a master secret
    key can control which functions a user can evaluate on encrypted data. It is a
    powerful primitive that even implies indistinguishability obfuscation (iO), given
    sufficiently compact ciphertexts (Ananth-Jain, CRYPTO’15 and Bitansky-Vaikuntanathan,
    FOCS’15). However, despite being extensively studied, there are FE schemes, such
    as function-hiding inner-product FE (Bishop-Jain-Kowalczyk, AC’15, Abdalla-Catalano-Fiore-Gay-Ursu,
    CRYPTO’18) and compact quadratic FE (Baltico-Catalano-Fiore-Gay, Lin, CRYPTO’17),
    that can be only realized using pairings. This raises the question if there are
    some mathematical barriers that hinder us from realizing these FE schemes from
    other assumptions.\r\n\r\nIn this paper, we study the difficulty of constructing
    lattice-based compact FE. We generalize the impossibility results of Ünal (EC’20)
    for lattice-based function-hiding FE, and extend it to the case of compact FE.
    Concretely, we prove lower bounds for lattice-based compact FE schemes which meet
    some (natural) algebraic restrictions at encryption and decryption, and have ciphertexts
    of linear size and secret keys of minimal degree. We see our results as important
    indications of why it is hard to construct lattice-based FE schemes for new functionalities,
    and which mathematical barriers have to be overcome.@eng"
  bibo_authorlist:
  - foaf_Person:
      foaf_givenName: Erkan
      foaf_name: Tairi, Erkan
      foaf_surname: Tairi
  - foaf_Person:
      foaf_givenName: Akin
      foaf_name: Ünal, Akin
      foaf_surname: Ünal
      foaf_workInfoHomepage: http://www.librecat.org/personId=f6b56fb6-dc63-11ee-9dbf-f6780863a85a
    orcid: 0000-0002-8929-0221
  bibo_doi: 10.1007/978-3-031-58723-8_9
  bibo_volume: 14652
  dct_date: 2024^xs_gYear
  dct_identifier:
  - UT:001278247600009
  dct_isPartOf:
  - http://id.crossref.org/issn/0302-9743
  - http://id.crossref.org/issn/1611-3349
  - http://id.crossref.org/issn/9783031587221
  dct_language: eng
  dct_publisher: Springer Nature@
  dct_title: Lower bounds for lattice-based compact functional encryption@
...