Method for authenticating a portable object, corresponding portable object, and apparatus therefor

• US 20030098775A1
• Filed: 01/09/2002
• Published: 05/29/2003
• Est. Priority Date: 05/09/2000
• Status: Active Grant

• Current Assignee: CP8 Technologies (Thales SA)
• Original Assignee: CP8 Technologies (Thales SA)
• Inventors: Hazard, Michel
• Granted Patent: US 6,977,577 B2
• Time in Patent Office: Days
• US Class Current: 340/5.8
• CPC Class Codes: G06Q 20/341 Active cards, i.e. cards including their own processing means, e.g. including an IC or chip
• CPC Class Codes: G06Q 20/4097 using mutual authentication between devices and transaction partners
• CPC Class Codes: G07F 7/082 Features insuring the integrity of the data on or in the card
• CPC Class Codes: G07F 7/1008 Active credit-cards provided with means to personalise their use, e.g. with PIN-introduction/comparison system

Abstract

The invention concerns a method for authenticating a portable object comprising information processing means and information storage means, the information storage means containing at least one code (i) defining operations capable of being executed by the portable object, as well as a one-way function.

According to the invention, this method comprises the step that consists of sending the portable object an order (31, 32i-34i, 35, 36) so that the latter executes a calculation of a result by applying to said one way function at least part of said code (i), this result being used to decide whether or not the portable object is authentic.

The invention also concerns the associated portable object and a device for cooperating with the portable object.

Claims

1. Method for authenticating a portable object (7) comprising information processing means (8) and information storage means (9, 10), the information storage means containing at least one code (i) defining operations capable of being executed by the portable object, as well as a one-way function, characterized in that it comprises the step that consists of sending the portable object an order (31, 32i-34i, 35, 36) so that the latter executes a calculation of a result by applying to said one-way function at least part of said code (i), this result being used to decide whether or not the portable object is authentic.

2. Method according to claim 1, wherein said result enters into the implementation of a given operation, this operation being performed successfully only when the portable object (7) is authentic.

3. Method according to claim 2, wherein said given operation comprises a decryption operation, said result making it possible to produce an associated decryption key.

4. Method according to claim 1, wherein said code part (i) used in the calculation comprises a machine code part.

5. Method according to claim 1, wherein the portable object (7) contains a so-called “

real”

code defining operations designed to be executed by the portable object, and a so-called “

dummy”

code defining operations not designed to be executed by the portable object, said code part used in the calculation comprising a dummy code part.

6. Method according to claim 1, wherein said order (31, 32i-34i, 35, 36) is sent to the portable object repeatedly during its life, prior to the execution by the latter of said operations.

7. Method according to claim 1, wherein said code part (i) used in the calculation is defined by a start address (32i) and an end address (33i) in the information storage means, said addresses being sent to the portable object.

8. Method according to claim 1, wherein said code (i) comprises a set of binary words, said code part used in the calculation being defined by a subset of binary words comprising the binary words distributed in the information storage means at a determined pitch (34i), said pitch being sent to the portable object.

9. Method for having a portable object (7) execute a sensitive operation, the portable object comprising information processing means (8) and information storage means (9, 10), the information storage means containing at least one code (i) defining operations capable of being executed by the portable object, as well as a one-way function, characterized in that it comprises the step that consists of sending the portable object an order (31, 32i-34i, 35, 36) so that the latter executes a calculation of a result by applying to said one-way function at least part of said code (i), said result entering into the implementation of said sensitive operation, this operation being performed successfully only when the portable object (7) is authentic.

10. Method according to claim 9, wherein said code part (i) used in the calculation comprises a machine code part.

11. Method according to claim 9, wherein the portable object contains a so-called “

reel”

code defining operations designed to be executed by the portable object, and a so-called “

dummy”

code defining operations not designed to be executed by the portable object, said code part used in the calculation comprising a dummy code part.

12. Portable object comprising information processing means (8) and information storage means (9, 10), the information storage means containing at least one code (i) defining operations capable of being executed by the portable object, as well as a one-way function, characterized in that it comprises means for executing a calculation of a result by applying to said one-way function at least part of said code.

13. Portable object according to claim 12, wherein said code part (i) used in the calculation comprises a machine code part.

14. Device (1) comprising information processing means (2) and information storage means (3, 4) and designed to communicate with a portable object (7) in order to authenticate the latter, the portable object comprising information processing means (8) and information storage means (9, 10), the information storage means of the portable object containing at least one code (i) defining operations capable of being executed by the portable object, as well as a one-way function, characterized in that it comprises means for sending the portable object an order (31, 32i-34i, 35, 36) so that the latter executes a calculation of a result by applying to said one-way function at least part of said code (i) of the portable object.

15. Device according to claim 14, wherein said code part (i) used in the calculation comprises a machine code part.