Method of protecting a microcomputer system against manipulation of data stored in a memory assembly of the microcomputer system

• US 20030028794A1
• Filed: 07/02/2002
• Published: 02/06/2003
• Est. Priority Date: 07/02/2001
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Miller, Norbert, Feilen, Oliver, Loechel, Norbert, Pischke, Juergen
• Granted Patent: US 8,095,801 B2
• Time in Patent Office: Days
• US Class Current: 713/193
• CPC Class Codes: G06F 21/54 by adding security routines or objects to programs

Abstract

A method of protecting a microcomputer system against manipulation of data stored in a memory assembly of the microcomputer system is provided. The method may protect, for example, a control program stored in the memory assembly of a motor vehicle control device. To secure and reliably protect the microcomputer system against manipulation of the data, the data is stored in the memory assembly marked or encrypted using an asymmetrical encryption method. The data may, for example, be encrypted outside the microcomputer system using an encryption algorithm and a private key, which is accessible to only a limited group of persons. The data may be decrypted in the microcomputer system using a decryption algorithm and a freely accessible public key.

Claims

1. A method of protecting a microcomputer system against manipulation of data stored in a memory assembly of the microcomputer system, the method comprising the steps of:

at least one of partially marking the data and partially encrypting the data using an asymmetrical encryption method in conjunction with one of a new programming and a reprogramming of the microcomputer system; and

transmitting the data to the memory assembly.

2. The method according to claim 1, wherein the at least one of partially marking the data and partially encrypting the data is performed outside of the microcomputer system using a private key and a predefinable encrypting algorithm, the private key being accessible only to a limited group of persons.

3. The method according to claim 2, further comprising the steps of:

reducing at least part of the data to a fingerprint using a compression algorithm, the reducing being performed outside of the microcomputer system;

forming a signature from the fingerprint using the private key; and

transmitting the signature with the data to the microcomputer system.

4. The method according to claim 1, further comprising the step of:

one of checking and decrypting the at least one of marked data and encrypted data, the one of checking and decrypting being performed in the microcomputer system using a freely accessible public key.

5. The method according to claim 3, further comprising the steps of:

decrypting the signature in the microcomputer system using the public key to generate a decrypted fingerprint;

forming a reference fingerprint from the part of the data reduced to the fingerprint using the compression algorithm, the reference fingerprint being formed using the compression algorithm; and

comparing the decrypted fingerprint to the reference fingerprint.

6. The method according to claim 4, wherein the one of checking and decrypting of the at least one of marked data and encrypted data is performed in the microcomputer system after one of a new programming and a reprogramming of the memory assembly.

7. The method according to claim 4, wherein the one of checking and decrypting of the at least one of marked data and encrypted data is performed in the microcomputer system while the microcomputer system powers up.

8. The method according to claim 7, wherein the one of checking and decrypting is performed in the microcomputer system in conjunction with a boot routine during power up.

9. The method according to claim 4, wherein the one of checking and decrypting of the at least one of marked data and encrypted data is performed in the microcomputer system in conjunction with a processing of the data.

10. The method according to claim 3, wherein a hash algorithm is utilized as the compression algorithm to form a hash value.

11. The method according to claim 1, wherein an RSA method is utilized as the asymmetrical encryption method.

12. A computer-readable memory medium for storing a plurality of instruction sets for execution in a computing device, the instruction sets performing the steps comprising:

i) at least one of partially marking data and partially encrypting the data using an asymmetrical encryption method in conjunction with one of a new programming and a reprogramming of the microcomputer system; and

ii) transmitting the data to a memory assembly.

13. The memory medium according to claim 12, wherein the memory medium includes one of a read-only memory, a random access memory and a flash memory.

14. The memory medium according to claim 12, wherein the computing device includes a microprocessor.

15. A computer program product in a computer readable medium for execution in a computing device, comprising:

i) means for at least one of partially marking data and partially encrypting the data using an asymmetrical encryption method in conjunction with one of a new programming and a reprogramming of the microcomputer system; and

ii) means for transmitting the data to a memory assembly.

16. The computer program product according to claim 15, wherein the computing device includes a microprocessor.

17. The computer program product according to claim 16, wherein the computer readable medium includes a flash memory element.

18. A microcomputer system, comprising:

a computing device having a memory assembly, in which data is stored;

a memory element; and

an arrangement operable to perform the following steps;

i) at least one of partially marking the data and partially encrypting the data using an asymmetrical encryption method in conjunction with one of a new programming and a reprogramming of the microcomputer system; and

ii) transmitting the data to the memory assembly.

19. The microcomputer system according to claim 18, wherein the arrangement includes a computer program stored on the memory element.