--- _id: '1643' abstract: - lang: eng text: We extend the notion of verifiable random functions (VRF) to constrained VRFs, which generalize the concept of constrained pseudorandom functions, put forward by Boneh and Waters (Asiacrypt’13), and independently by Kiayias et al. (CCS’13) and Boyle et al. (PKC’14), who call them delegatable PRFs and functional PRFs, respectively. In a standard VRF the secret key sk allows one to evaluate a pseudorandom function at any point of its domain; in addition, it enables computation of a non-interactive proof that the function value was computed correctly. In a constrained VRF from the key sk one can derive constrained keys skS for subsets S of the domain, which allow computation of function values and proofs only at points in S. After formally defining constrained VRFs, we derive instantiations from the multilinear-maps-based constrained PRFs by Boneh and Waters, yielding a VRF with constrained keys for any set that can be decided by a polynomial-size circuit. Our VRFs have the same function values as the Boneh-Waters PRFs and are proved secure under the same hardness assumption, showing that verifiability comes at no cost. Constrained (functional) VRFs were stated as an open problem by Boyle et al. alternative_title: - LNCS author: - first_name: Georg full_name: Fuchsbauer, Georg id: 46B4C3EE-F248-11E8-B48F-1D18A9856A87 last_name: Fuchsbauer citation: ama: 'Fuchsbauer G. Constrained Verifiable Random Functions . In: Abdalla M, De Prisco R, eds. SCN 2014. Vol 8642. Springer; 2014:95-114. doi:10.1007/978-3-319-10879-7_7' apa: 'Fuchsbauer, G. (2014). Constrained Verifiable Random Functions . In M. Abdalla & R. De Prisco (Eds.), SCN 2014 (Vol. 8642, pp. 95–114). Amalfi, Italy: Springer. https://doi.org/10.1007/978-3-319-10879-7_7' chicago: Fuchsbauer, Georg. “Constrained Verifiable Random Functions .” In SCN 2014, edited by Michel Abdalla and Roberto De Prisco, 8642:95–114. Springer, 2014. https://doi.org/10.1007/978-3-319-10879-7_7. ieee: G. Fuchsbauer, “Constrained Verifiable Random Functions ,” in SCN 2014, Amalfi, Italy, 2014, vol. 8642, pp. 95–114. ista: 'Fuchsbauer G. 2014. Constrained Verifiable Random Functions . SCN 2014. SCN: Security and Cryptography for Networks, LNCS, vol. 8642, 95–114.' mla: Fuchsbauer, Georg. “Constrained Verifiable Random Functions .” SCN 2014, edited by Michel Abdalla and Roberto De Prisco, vol. 8642, Springer, 2014, pp. 95–114, doi:10.1007/978-3-319-10879-7_7. short: G. Fuchsbauer, in:, M. Abdalla, R. De Prisco (Eds.), SCN 2014, Springer, 2014, pp. 95–114. conference: end_date: 2014-09-05 location: Amalfi, Italy name: 'SCN: Security and Cryptography for Networks' start_date: 2014-09-03 date_created: 2018-12-11T11:53:13Z date_published: 2014-01-01T00:00:00Z date_updated: 2021-01-12T06:52:12Z day: '01' department: - _id: KrPi doi: 10.1007/978-3-319-10879-7_7 ec_funded: 1 editor: - first_name: Michel full_name: Abdalla, Michel last_name: Abdalla - first_name: Roberto full_name: De Prisco, Roberto last_name: De Prisco intvolume: ' 8642' language: - iso: eng main_file_link: - open_access: '1' url: http://eprint.iacr.org/2014/537 month: '01' oa: 1 oa_version: Submitted Version page: 95 - 114 project: - _id: 258C570E-B435-11E9-9278-68D0E5697425 call_identifier: FP7 grant_number: '259668' name: Provable Security for Physical Cryptography publication: SCN 2014 publication_status: published publisher: Springer publist_id: '5509' scopus_import: 1 status: public title: 'Constrained Verifiable Random Functions ' type: conference user_id: 4435EBFC-F248-11E8-B48F-1D18A9856A87 volume: 8642 year: '2014' ...