Paper 2011/239
Efficient Software Implementations of Modular Exponentiation
Shay Gueron
Abstract
RSA computations have a significant effect on the workloads of SSL/TLS servers, and therefore their software implementations on general purpose processors are an important target for optimization. We concentrate here on 512-bit modular exponentiation, used for 1024-bit RSA. We propose optimizations in two directions. At the primitives’ level, we study and improve the performance of an “Almost” Montgomery Multiplication. At the exponentiation level, we propose a method to reduce the cost of protecting the w-ary exponentiation algorithm against cache/timing side channel attacks. Together, these lead to an efficient software implementation of 512-bit modular exponentiation, which outperforms the currently fastest publicly available alternative. When measured on the latest x86-64 architecture, the 2nd Generation Intel® Core™ processor, our implementation is 43% faster than that of the current version of OpenSSL (1.0.0d).
Note: Fixing some problems with referencing figures/algorithms in the document.
Metadata
- Available format(s)
-
PDF
- Publication info
- Published elsewhere. Unknown where it was published
- Keywords
- modular arithmeticmodular exponentiationMontgomery multiplicationRSA.
- Contact author(s)
- shay @ math haifa ac il
- History
- 2011-06-28: revised
- 2011-05-18: received
- See all versions
- Short URL
- https://ia.cr/2011/239
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2011/239,
author = {Shay Gueron},
title = {Efficient Software Implementations of Modular Exponentiation},
howpublished = {Cryptology {ePrint} Archive, Paper 2011/239},
year = {2011},
url = {https://eprint.iacr.org/2011/239}
}