Protection of a modular exponentiation calculation by addition of a random quantity
US9014368B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 6, 2012 |
| Grant date | Apr 21, 2015 |
| Priority date | — |
| Expiry date | Apr 10, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2207/7238
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A method for protecting a calculation, by an electronic circuit, of a modular exponentiation of a digital quantity, wherein: a first variable is initialized with a random quantity increased by once unit; a second variable is initialized with the product of the digital quantity by the random quantity; a third variable is initialized with the digital quantity; iteratively for all the bits at 1 of an exponent of the modular exponentiation, the first variable is updated by: a) multiplying its content by that of the third variable; and b) subtracting thereto the content of the second variable increased by the random quantity; and once all the bits of the exponent have been processed, the content of the first variable is decreased by the random quantity to provide the result of the modular exponentiation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.