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:
Oct. 26, 2010
Filed:
Dec. 22, 2006
Michel Douguet, Marseilles, FR;
Vincent Dupaquis, Biver, FR;
Michel Douguet, Marseilles, FR;
Vincent Dupaquis, Biver, FR;
Atmel Rousset S.A.S., Rousset Cedex, FR;
Abstract
A method of protecting secret key integrity in a hardware cryptographic system includes first obtaining an encryption result and corresponding checksum of known data using the secret key, saving those results, then masking the secret key and storing the masked key. When the masked key is to be used in a cryptographic application, the method checks key integrity against fault attacks by decrypting the prior encryption results using the masked key. If upon comparison, the decryption result equals valid data, then the key's use in the cryptographic system can proceed. Otherwise, all data relating to the masked key is wiped from the system and fault injection is flagged.