Paper 2016/524 Original: eprint.iacr.org/2016/524 ↗
Single-Key to Multi-Key Functional Encryption with Polynomial Loss
Abstract
Functional encryption (FE) enables fine-grained access to encrypted data. In a FE scheme, the holder of a secret key $\SK_f$ (associated with a function $f$) and a ciphertext $c$ (encrypting plaintext $x$) can learn $f(x)$ but nothing more. An important parameter in the security model for FE is the number of secret keys that adversary has access to. In this work, we give a transformation from a FE scheme for which the adversary gets access to a single secret key (with ciphertext size sub-linear in the circuit for which this secret key is issued) to one that is secure even if adversary gets access to an {unbounded} number of secret keys. A novel feature of our transformation is that its security proof incurs only a {\em polynomial} loss.
Metadata
- Available format(s)
PDF- Category
- Public-key cryptography
- Publication info
- Preprint.
- History
- 2016-08-23: last updated
- 2016-05-29: published
- Short URL
- https://ia.cr/2016/524
- License
- https://creativecommons.org/licenses/by/4.0/
BibTeX
@misc{cryptoeprint:2016/524,
author = {Sanjam Garg and Akshayaram Srinivasan},
title = {Single-Key to Multi-Key Functional Encryption with Polynomial Loss},
howpublished = {Cryptology {ePrint} Archive, Paper 2016/524},
year = {2016},
url = {https://eprint.iacr.org/2016/524}
}