Paper 2002/161
Practical Verifiable Encryption and Decryption of Discrete Logarithms
Jan Camenisch and Victor Shoup
Abstract
This paper presents a variant of the new public key encryption of Cramer and Shoup based on Paillier's decision composite residuosity assumption, along with an efficient protocol for verifiable encryption of discrete logarithms. This is the first verifiable encryption system that provides chosen ciphertext security and avoids inefficient cut-and-choose proofs. This has numerous applications, including fair exchange and key escrow. We also present efficient protocols for verifiable decryption, which has applications to, e.g., confirmer signatures. The latter protocols build on a new protocol for proving whether or not two discrete logarithms are equal that is of independent interest. Prior such protocols were either inefficient or not zero-knowledge.
Metadata
- Available format(s)
-
PDF
PS
- Category
- Cryptographic protocols
- Publication info
- Published elsewhere. extented abstract in Crypto 2003
- Contact author(s)
- jca @ zurich ibm com
- History
- 2003-08-25: last of 2 revisions
- 2002-11-01: received
- See all versions
- Short URL
- https://ia.cr/2002/161
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2002/161,
author = {Jan Camenisch and Victor Shoup},
title = {Practical Verifiable Encryption and Decryption of Discrete Logarithms},
howpublished = {Cryptology {ePrint} Archive, Paper 2002/161},
year = {2002},
url = {https://eprint.iacr.org/2002/161}
}
