The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 01, 2018
Filed:
Sep. 10, 2015
Nxp B.v., Eindhoven, NL;
NXP B.V., Eindhoven, NL;
Abstract
Methods of securing a cryptographic device against implementation attacks, are described. A disclosed method comprises the steps of obtaining a key () from memory of the cryptographic device; providing the key and a constant input () to an encryption module (); deriving an output () of encrypted data bits using the encryption module (); providing the output (), the key () and an input vector () to a key update module (); and using said key update module () to modify the key based on at least a part () of the input vector () to derive an updated key (). This prevents the value of the key from being derived using the updated key or by using side-channel attacks because the input is constant for all keys. Additionally, by altering the input vector, the updated key is also altered.