System and method for cryptographic processing in a time window
AssigneeElliptic Technologies Inc.
InventorsNeil HAMILTON, François BOURDON, Michael BORZA
Life of this patent
Estimating the term…
Abstract
A method is disclosed for providing first data and a first secret key to a cipher processor for ciphering. The first data is ciphered in accordance with a first cipher process and the first secret key to provide output data. Before ciphering of the first data, extra data is inserted within the cipher processor for ciphering in accordance with at least a portion of said first cipher process. The extra data is inserted within a sequence of cipher processor operations for obfuscating the output data.
Claims28
A method comprising:
- providing first data and a first secret key to a cipher processor for ciphering;
- said cipher processor ciphering the first data in accordance with a first cipher process and the first secret key to provide output data;
- and
- before ciphering of the first data, inserting extra data within the cipher processor for ciphering in accordance with at least a portion of said first cipher process, said extra data inserted within a sequence of cipher processor operations for obfuscating said output data.
A method for leak resistant ciphering comprising:
- providing a first stream of data and an associated first secret key;
- expanding the associated first secret key to form an associated first expanded secret key;
- ciphering a plurality of guard rounds before processing the first data stream;
- ciphering the first data stream in accordance with the associated first expanded secret key;
- ciphering a plurality of guard rounds after processing the first data stream;
- and
- providing the ciphered first stream of data at an output port.
A cipher processor comprising:
- a key store for storing a first secret key;
- a first data store for storing at least a portion of first data for ciphering thereof;
- and
- a cipher processor for processing the first data in accordance with a first cipher process and the first secret key to provide output data therefrom, and for during processing of the first data inserting within the cipher processor at least a portion of the first data comprising at least a guard round for being processed thereby in accordance with a portion of a same cipher process, the at least a guard round inserted within a sequence of cipher processor operations for obfuscating operation thereof
Dependencies are inferred from the claim text.