Method for protecting a microcomputer system against manipulation of data stored in a storage assembly

• US 20030018902A1
• Filed: 07/01/2002
• Published: 01/23/2003
• Est. Priority Date: 07/02/2001
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Schneider, Klaus, Illg, Bernd, Beuten, Michael
• Granted Patent: US 7,313,703 B2
• Time in Patent Office: Days
• US Class Current: 713/187
• CPC Class Codes: G11C 16/22 Safety or protection circuits preventing unauthorised or accidental access to memory cells

Abstract

A method of protecting a microcomputer system against manipulation of data stored in a storage assembly of the microcomputer system, in particular a control program stored there. Checking mechanisms are executed at preselectable points in times to check for manipulation of the data. To achieve the most complete test coverage within an acceptable period of time in checking data stored in a storage assembly of a microcomputer system, the storage assembly is subdivided into multiple logic blocks, at least one of the blocks is selected and the checking mechanisms are executed only for the or each selected block of the storage assembly.

Claims

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

executing at least one check mechanism at at least one preselectable point in time to check for manipulation of the data;

subdividing the storage assembly into a plurality of logic blocks;

selecting at least one logic block of the plurality of logic blocks; and

executing the at least one check mechanism at at least one preselectable point in time to check for manipulation of the at least one logic block.

2. The method of claim 1, wherein the data stored in the storage assembly includes a control program.

3. The method of claim 1, wherein the at least one check mechanism is executed in powering up the microcomputer system.

4. The method of claim 1, wherein the at least one logic block is selected randomly.

5. The method of claim 4, further comprising:

reading a noise signal at an analog/digital input of the microcomputer system;

generating a random number as a function of the noise signal;

forming a sum of contents in the storage assembly, the contents being disordered before the microsystem is powered up;

generating a random number as a function of the sum;

reading out a status of a timer inside the microcomputer system that is not reset when the microsystem is powered up;

generating a random number as a function of the status of the timer;

reading out a variable influenceable by a driver of a vehicle into which the microcomputer system is integrated; and

generating a random number as a function of the variable.

6. The method of claim 1, further comprising:

storing, after executing the at least one check mechanism, an entry into a storage area of the storage assembly in a write-protected form and one that may not be read out;

erasing the storage area when one of reprogramming and newly programming the storage assembly; and

checking the entry when the microcomputer system is powered up.

7. A microcomputer system comprising:

a computer;

a storage assembly to store data;

a subdividing arrangement to subdivide the storage assembly into a plurality of logic blocks;

a selecting arrangement to select at least one logic block of the plurality of logic blocks; and

an executing arrangement to execute at least one check mechanism at at least one preselectable point in time to check for manipulation of at least one of the data and the at least one logic block.

8. The microcomputer system of claim 7, wherein the computer includes a microprocessor.

9. The microcomputer system of claim 7, wherein the data stored in the storage assembly includes a control program.

10. The microcomputer system of claim 7, wherein the microcomputer system is configured as a control device for a motor vehicle for one of controlling and regulating an automotive function.

11. The microcomputer system of claim 7, further comprising:

a computer program executable by the computer, the computer program comprising program code for protecting the microcomputer system against manipulation of data stored in the storage assembly of the microcomputer system by performing the steps of;

executing at least one check mechanism at at least one preselectable point in time to check for manipulation of the data;

subdividing the storage assembly into a plurality of logic blocks;

selecting at least one logic block from the plurality of logic blocks; and

executing the at least one check mechanism at at least one preselectable point in time to check for manipulation of the at least one logic block.

12. The microcomputer system of claim 11, wherein the computer program is stored in the storage assembly.

13. The microcomputer system of claim 7, wherein the storage assembly is arranged on a same semiconductor component as the computer.

14. A computer program storable at a memory and executable by a computer, the computer program comprising program code for protecting a microcomputer system against manipulation of data stored in a storage assembly of the microcomputer system by performing the steps of:

executing at least one check mechanism at at least one preselectable point in time to check for manipulation of the data;

subdividing the storage assembly into a plurality of logic blocks;

selecting at least one logic block from the plurality of logic blocks; and

executing the at least one check mechanism at at least one preselectable point in time to check for manipulation of the at least one logic block.