[Resource Topic] 2019/314: Optimal Bounded-Collusion Secure Functional Encryption

Welcome to the resource topic for 2019/314

Title:
Optimal Bounded-Collusion Secure Functional Encryption

Authors: Prabhanjan Ananth, Vinod Vaikuntanathan

Abstract:

We construct private-key and public-key functional encryption schemes secure against adversaries that corrupt an a-priori bounded number of users and obtain their functional keys, from minimal assumptions. For a collusion bound of Q=Q(\lambda) (where \lambda is the security parameter), our public-key (resp. private-key) functional encryption scheme (a) supports the class of all polynomial-size circuits; (b) can be built solely from a vanilla public-key (resp. private-key) encryption scheme; and (c) has ciphertexts that grow linearly with the collusion bound Q. Previous constructions were sub-optimal with respect to one or more of the above properties. The first two of these properties are the best possible and any improvement in the third property, namely the ciphertext size dependence on the collusion bound Q, can be used to realize an indistinguishability obfuscation scheme. In addition, our schemes are adaptively secure and make black-box use of the underlying cryptographic primitives.

ePrint: https://eprint.iacr.org/2019/314

See all topics related to this paper.

Feel free to post resources that are related to this paper below.

Example resources include: implementations, explanation materials, talks, slides, links to previous discussions on other websites.

For more information, see the rules for Resource Topics .