Paper 2017/956
Threshold Cryptosystems From Threshold Fully Homomorphic Encryption
Dan Boneh, Rosario Gennaro, Steven Goldfeder, Aayush Jain, Sam Kim, Peter M. R. Rasmussen, and Amit Sahai
Abstract
We develop a general approach to adding a threshold functionality to a large class of (non- threshold) cryptographic schemes. A threshold functionality enables a secret key to be split into a number of shares, so that only a threshold of parties can use the key, without reconstructing the key. We begin by constructing a threshold fully-homomorphic encryption scheme (TFHE) from the learning with errors (LWE) problem. We next introduce a new concept, called a universal thresholdizer, from which many threshold systems are possible. We show how to construct a universal thresholdizer from our TFHE. A universal thresholdizer can be used to add threshold functionality to many systems, such as CCA-secure public key encryption (PKE), signature schemes, pseudorandom functions, and others primitives. In particular, by applying this paradigm to a (non-threshold) lattice signature system, we obtain the first single-round threshold signature scheme from LWE.
Note: This is a merged version of Eprint 2017/251 and 2017/257, with additional results.
Metadata
- Available format(s)
- Category
- Cryptographic protocols
- Publication info
- Preprint. MINOR revision.
- Keywords
- fully homomorphic encryptionthreshold cryptographylatticesthreshold signatures
- Contact author(s)
- skim13 @ cs stanford edu
- History
- 2017-09-29: received
- Short URL
- https://ia.cr/2017/956
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2017/956, author = {Dan Boneh and Rosario Gennaro and Steven Goldfeder and Aayush Jain and Sam Kim and Peter M. R. Rasmussen and Amit Sahai}, title = {Threshold Cryptosystems From Threshold Fully Homomorphic Encryption}, howpublished = {Cryptology {ePrint} Archive, Paper 2017/956}, year = {2017}, url = {https://eprint.iacr.org/2017/956} }