Paper 2007/119 Original: eprint.iacr.org/2007/119 ↗
Rerandomizable RCCA Encryption
Abstract
We give the first perfectly rerandomizable, Replayable-CCA (RCCA) secure encryption scheme, positively answering an open problem of Canetti et al. [CRYPTO 2003]. Our encryption scheme, which we call the Double-strand Cramer-Shoup scheme, is a non-trivial extension of the popular Cramer-Shoup encryption. Its security is based on the standard DDH assumption. To justify our definitions, we define a powerful "Replayable Message Posting" functionality in the Universally Composable (UC) framework, and show that any encryption scheme that satisfies our definitions of rerandomizability and RCCA security is a UC-secure implementation of this functionality. Finally, we enhance the notion of rerandomizable RCCA security by adding a receiver-anonymity (or key-privacy) requirement, and show that it results in a correspondingly enhanced UC functionality. We leave open the problem of constructing a scheme that achieves this enhancement.
Metadata
- Available format(s)
PDF- Category
- Public-key cryptography
- Publication info
- Preprint.
- History
- 2007-08-17: last updated
- 2007-04-03: published
- Short URL
- https://ia.cr/2007/119
- License
- https://creativecommons.org/licenses/by/4.0/
BibTeX
@misc{cryptoeprint:2007/119,
author = {Manoj Prabhakaran and Mike Rosulek},
title = {Rerandomizable RCCA Encryption},
howpublished = {Cryptology {ePrint} Archive, Paper 2007/119},
year = {2007},
url = {https://eprint.iacr.org/2007/119}
}