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:
Sep. 22, 2015
Filed:
May. 24, 2013
Apple Inc., Cupertino, CA (US);
Benoit Chevallier-Mames, Paris, FR;
Mathieu Ciet, Paris, FR;
Thomas Icart, Paris, FR;
Bruno Kindarji, Paris, FR;
Augustin J. Farrugia, Los Altos Hills, CA (US);
Apple Inc., Cupertino, CA (US);
Abstract
Various embodiments of a computer-implemented method of information security using block cipher column rotations are described. The cipher state column rotations provide resistance to white box side channel memory correlation attacks designed to reverse-engineer a symmetric cipher key associated with the information security system. The column rotation operations can be performed on the cipher state of a block cipher, and then removed from the result, to provide obfuscation of the data when in memory, while not impacting the resulting output of the cipher or decipher operation. The method additionally includes performing a first rotation of an iteration specific cipher subkey according to the first rotation index, performing an iteration of the block cipher operations on the cipher state matrix, and rotating the columns of the cipher state matrix according to an inverse of the first rotation index.