Patent · US Active

Protecting cryptographic key data

US11456854B2 · kind B2 · utility

1Cited by

0References

18Claims

0Family size

Assignee

Nordic Semiconductor ASA · NO

Inventors

Kauko Kutti · Trondheim, NO
Jarmo Veikkola · Trondheim, NO
Marko Winblad · Trondheim, NO

Key dates

Filing date	Feb 14, 2019
Grant date	Sep 27, 2022
Priority date	—
Expiry date	Aug 9, 2039

Classification

Technology area (CPC H)Electricity
CPC primaryH04L9/0894
WIPO fieldDigital communication
WIPO sectorElectrical engineering

Abstract

A cryptographic module is switchable between a key-input mode and a data-input mode. In the key-input mode, the cryptographic module receives key data, key length information and first input data, combines an amount of the key data corresponding to the key length information with the first input data to produce combined data, wherein a key-influenced length of the combined data is the shortest length of the combined data that contains every data bit of the combined data whose value depends on the key data. It performs a cryptographic operation on the combined data to generate first output data and does not output any of the first output data until after the cryptographic operation has been applied to all of the key-influenced length of the combined data. In the data-input mode of operation, the cryptographic module receives a quantity of second input data whose length can be less than said key-influenced length, performs the cryptographic operation on the second input data to generate second output data and outputs the second output data.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.