Morpho

Idemia Identity & Security France

Thanh Ha Le

Julien Bringer

Herve Chabanne

Hervé Chabanne

Louis-Philippe Goncalves

Maël Berthier

A functional program stored in a memory area of an electronic card may be protected against an attack by disturbance of electrical origin intended to modify at least one logic state of at least one code of this program. The method may include: a storage step during which codes of the functional program and codes of a check program intended to check the logical behavior of the functional program are stored in the memory of the card; and a step of executing at least one code of the functional program followed by a step of checking the logic states of the functional program by executing the check program. During the storage step, the codes of the check program are stored in a memory area formed by addresses that are defined so that the attack by disturbance of electrical origin has no influence on the logic states of this program.

Method for protecting a chip card against a physical attack intended to modify the logical behaviour of a functional program

The invention relates in particular to a method for securing the execution of a cryptographic algorithm (ALG) against passive sniffing, the method implementing masking (MSK) of data processed by the cryptographic algorithm. The masking (MSK) of said data includes a linear encoding step such as x'=x&#xb7;L+c, in which x is the data to be masked, x&#x2032; is the corresponding masked data, c is a code word included in a linear code C, and L is a matrix made up of linearly independent vectors not included in the linear code C. The invention also relates to a device (SC) implementing such a method.

Protection against passive sniffing

Growing community of inventors

Issy-les-Moulineaux, France

Thanh Ha Le