Methods and arrangements for limiting access to computer controlled functions and devices

• US 6,971,015 B1
• Filed: 03/29/2000
• Issued: 11/29/2005
• Est. Priority Date: 03/29/2000
• Status: Expired due to Fees

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Falcon, Stephen Russell, Yip, Clement Chun Pong
• Primary Examiner(s): Morse, Gregory
• Assistant Examiner(s): Tran, Tongoc
• Application Number:
  US09/538,621
• Time in Patent Office: 2,071 Days
• Field of Search: 713/201, 713/200, 713/202, 713/182, 713/168, 713/156, 707/9, 707/10, 707/201, 707/3, 700/83, 700/17, 710/11, 710/30, 709/224, 709/226, 709/228, 709/212, 709/217, 709/223, 709/247, 709/318, 709/322, 709/320, 709/229, 709/227, 701/1, 701/29, 701/32, 701/36, 701/93, 701/97, 701/98, 701/3, 701/49, 701/41
• US Class Current: 713/182
• CPC Class Codes: G06F 21/572 Secure firmware programming, e.g. of basic input output system [BIOS]

Abstract

Methods and arrangements are provided verify if a requesting computer application is authorized to change a controlled parameter associated with a computer controlled device and/or function. To accomplish this, one or verification functions are employed to analyze a security code or absence thereof, as identified by a requesting application. If the security code, which may be encrypted, matches a known or calculated valid security code, then the requesting application is deemed to be authorized to change the controlled parameter and/or modify certain limitations associated with an acceptable range for the controlled parameter. If the security code does not match a known or calculated valid security code, then the requesting application is deemed to be unauthorized to change the controlled parameter outside of a previously established acceptable range for the controlled parameter. The verification function can be implemented in a ROM to increase the security and to thwart attempts to circumvent the authorization scheme. Several independent verification functions can be arranged to support the verification of a plurality of authorized applications.

Claims

1. A method comprising:

verifying that a first application is authorized to set an initial range for a controlled parameter setting;

if authorized, allowing the first application to set an initial range for the controlled parameter setting;

subsequently, allowing at least a second application to modify the controlled parameter setting within the initial range set by the first application;

verifying that the second application is authorized to modify a current range for the controlled parameter setting;

if authorized allowing the second application to modify the current range for the controlled parameter setting; and

subsequently, allowing at least a third application to modify the controlled parameter setting within the current range as modified by the second application,

wherein

verifying that the first application is authorized to set the initial range for the controlled parameter setting further includes using a first verifier; and

verifying that the second application is authorized to modify the current range for the controlled parameter setting further includes using a second verifier,

wherein the first verifier and the second verifier are operatively configured in a serial arrangement, and the first verifier is independently responsive to a first security code and the second verifier is independently responsive to a second security code.

2. A method as recited in claim 1 wherein the first and second security codes are at least partially encrypted.

3. A method as recited in claim 1 wherein the first and second applications are verified based at least partially on memory location information associated with a verifying function.

4. A method as recited in claim 3, wherein the memory location information associated with the verifying function defines memory location within a read only memory (ROM).

5. A method as recited in claim 1 wherein the initial range includes at least a maximum controlled parameter setting, and the second application is not allowed to modify the controlled parameter setting beyond the maximum controlled parameter setting.

6. A method as recited in claim 1 wherein the initial range includes at least a minimum controlled parameter setting, and the second application is not allowed to modify the controlled parameter setting below the minimum controlled parameter setting.

7. A method as recited in claim 1 wherein the controlled parameter setting is selected from a group of settings comprising an audio volume control parameter, an audio tone control parameter, an illumination control parameter, a visual display control parameter, a temperature control parameter, a communication access control parameter, a peripheral device control parameter, a vehicle control parameter, and an environment control parameter.

8. A method as recited in claim 1 wherein the first verifier is provided by a first entity and the second verifier that is provided by a second entity.

9. A method as recited in claim 1 wherein the first security code and the second security code are the same.

10. A method as recited in claim 1 wherein the first security code is provided by a first entity and the second security code is provided by a second entity.

11. A computer-readable medium having computer-executable instructions for performing steps comprising:

verifying that a first application is authorized to set an initial range for a controlled parameter setting;

if authorized, allowing the first application to set an initial range for the controlled parameter setting;

subsequently, allowing at least a second application to modify the controlled parameter setting within the initial range set by the first application;

verifying that the second application is authorized to modify a current range for the con trolled parameter setting;

if authorized, allowing the second application to modify the current range for the controlled parameter setting; and

subsequently, allowing at least a third application to modify the controlled parameter setting within the current range as modified by the second application;

wherein

verifying that the first application is authorized to set the initial range for the controlled parameter setting further includes using a first verifier; and

verifying that the second application is authorized to modify the current range for the controlled parameter setting further includes using a second verifier,

wherein the first verifier and the second verifier are operatively configured in a serial arrangement, and the first verifier is independently responsive to a first security code and the second verifier is independently responsive to a second security code.

12. A computer-readable medium as recited in claim 11 wherein the first and second security codes are at least partially encrypted.

13. A computer-readable medium as recited in claim 11 wherein the first and second applications are verified based at least partially on memory location information associated with a verifying function.

14. A computer-readable medium as recited in claim 13 wherein the memory location information associated with the verifying function defines memory location within a read only memory (ROM).

15. A computer-readable medium as recited in claim 11 wherein the initial range includes at least a maximum controlled parameter setting, and the second application is not allowed to modify the controlled parameter setting beyond the maximum controlled parameter setting.

16. A computer-readable medium as recited in claim 11 wherein the initial range includes at least a minimum controlled parameter setting, and the second application is not allowed to modify the controlled parameter setting below the minimum controlled parameter setting.

17. A computer-readable medium as recited in claim 11 wherein the controlled parameter setting is selected from a group of settings comprising an audio volume control parameter, an audio tone control parameter, an illumination control parameter, a visual display control parameter, a temperature control parameter, a communication access control parameter, a peripheral device control parameter, a vehicle control parameter, and an environment control parameter.

18. A computer-readable medium as recited in claim 11 wherein the first verifier is provided by a first entity and the second verifier that is provided by a second entity.

19. A computer-readable medium as recited in claim 11 wherein the first security code and the second security code are the same.

20. A computer-readable medium as recited in claim 11 wherein the first security code is provided by a first entity and the second security code is provided by a second entity.