Modular exponentiation with transparent side channel attack countermeasures
US10367637B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 22, 2016 |
| Grant date | Jul 30, 2019 |
| Priority date | — |
| Expiry date | Jul 16, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2209/12
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A method of implementing security in a modular exponentiation function for cryptographic operations is provided. A key is obtained as a parameter when the modular exponentiation function is invoked. The key may be one of either a public key or a private key of a cryptographic key pair. Within the modular exponentiation function, the method ascertains whether the key is greater than L bits long, where L is a positive integer. A countermeasure against an attack is implemented if the key is greater than L bits long. The countermeasure may include one or more techniques (e.g., hardware and/or software techniques) that inhibit or prevent information about the key from being ascertained through analysis. One or more exponentiation operations may then be performed using the key. The same modular exponentiation function may be used to perform encryption and decryption operations but with different keys.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.