Paper 2016/524
Single-Key to Multi-Key Functional Encryption with Polynomial Loss
Sanjam Garg and Akshayaram Srinivasan
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)
- Category
- Public-key cryptography
- Publication info
- A minor revision of an IACR publication in TCC 2016
- Keywords
- Functional EncryptionIND-based securitygeneric transforms
- Contact author(s)
- akshayaram @ berkeley edu
- History
- 2016-08-23: last of 2 revisions
- 2016-05-29: received
- See all versions
- Short URL
- https://ia.cr/2016/524
- License
-
CC BY
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} }