Protecting cryptographic operations using conjugacy class functions
US9565018B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 30, 2014 |
| Grant date | Feb 7, 2017 |
| Priority date | — |
| Expiry date | Oct 2, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2209/76
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
Some embodiments provide for an improved method for performing AES cryptographic operations. The method applies a look up table operation that includes several operations embedded within look up tables. The embedded operations include a permutation operation to permute several bytes of AES state, a multiplication operation to apply a next round's protection to the AES state, an affine function and an inverse affine function to conceal the multiplication operation, and an inverse permutation operation to remove a previous round's protection. Some embodiments provide for an optimized method for efficiently performing such protected AES operations. The method alternates rounds of AES processing between software processing (e.g. processing by a CPU, performed according to software instructions) and hardware processing (e.g. processing by cryptographic ASIC).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.