Secured sensor interface

Patent metadata

Field	Value
Publication number	US-10467890-B2
Application number	US-201615154795-A
Country	US
Kind code	B2
Filing date	May 13, 2016
Priority date	May 13, 2016
Publication date	Nov 5, 2019
Grant date	Nov 5, 2019

Abstract

Examples are disclosed that relate to the securing of a distributed sensor system. One example provides a security component configured to be communicatively coupled between a trusted element and a distributed sensor system. The security component includes a configuration table configured to store sensor configurations for the distributed sensor system, and a security controller configured to secure the configuration table by limiting access to the configuration table according to a selected security protocol. The security component further includes a feedback controller configured to receive signals from the distributed sensor system and send feedback instructions to the trusted element based at least on a comparison of the signals received from the distributed sensor system with values in the configuration table.

First claim

The invention claimed is:

1. A security component disposed communicatively between a trusted element of an application processor and a distributed sensor system of an electronic device, the distributed sensor system comprising a power management component, the security component comprising:
a configuration table in which sensor configurations for the distributed sensor system are stored, the sensor configurations comprising one or more sensor limits for one or more sensors of the distributed sensor system, the one or more sensor limits defining limits to which to compare sensor signals for controlling operation of the power management component of the distributed sensor system;
a security controller configured to secure the configuration table by limiting access to the configuration table according to a selected security protocol; and
a feedback controller configured to receive signals from the distributed sensor system and send feedback instructions to one or more of the power management component and the trusted element of the application processor based at least on a comparison of the signals received from the distributed sensor system with values in the configuration table, the feedback controller being further configured to compare a sensor limit stored in the configuration table to a value stored in a register of a sensor of the distributed sensor system, and take an action comprising a system shutdown to prevent a possible attack when the sensor limit in the configuration table and the value stored in the register of the sensor differ.

2. The security component of claim 1 , wherein the sensor configurations include one or more of sensor limits and programmable behaviors for the distributed sensor system.

3. The security component of claim 1 , wherein the selected security protocol includes a time-windowed modification protocol in which the stored sensor configurations are modifiable within a predefined time period and not modifiable outside of the predefined time period.

4. The security component of claim 3 , wherein the predefined time period comprises a time period triggered by one or more of a reset and a power event.

5. The security component of claim 1 , wherein the selected security protocol includes a locking-bit protection protocol that locks the stored sensor configurations in registers of the security component upon storing of the stored sensor configurations.

6. The security component of claim 5 , wherein the security component is configured to maintain the registers of the security component as locked until a reset or power event occurs.

7. The security component of claim 1 , wherein the selected security protocol includes host and device authorization in which the stored sensor configurations are modifiable only by an authenticated device.

8. The security component of claim 1 , wherein the feedback controller is further configured to detect an unauthorized modification event based on a comparison of values in the configuration table and values in registers of the distributed sensor system, and send a shutdown instruction to the power management component of the distributed sensor system responsive to detecting the unauthorized modification event comprising unauthorized modification of the configuration table.

9. The security component of claim 8 , wherein the feedback controller is configured to clear the shutdown instruction only upon receipt of an authenticated request to clear the shutdown instruction.

10. The security component of claim 1 , wherein the security component comprises one or more of a field-programmable gate array (FPGA), an application-specific integrated circuit (ASIC), and a component of a system-on-chip (SoC).

11. A method of securing a configuration table of a security component, the security component disposed communicatively between a trusted element of an application processor and a distributed sensor system of an electronic device, the distributed sensor system comprising a power management component, the configuration table storing sensor configurations for the distributed sensor system, the method comprising:
receiving updated sensor configurations for the distributed sensor system;
when the updated sensor configurations are received in compliance with a selected security protocol, the selected security protocol comprising time windowing in which the stored sensor configurations are modifiable only by an authenticated device within a predefined time period, then adjusting the stored sensor configurations in the configuration table based on the updated sensor configurations, the stored sensor configurations comprising one or more sensor limits for one or more sensors of the distributed sensor system, the sensor limits defining limits to which to compare sensor signals for controlling operation of the power management component of the distributed sensor system;
when the updated sensor configurations are not received in compliance with the selected security protocol, not adjusting the stored sensor configurations in the configuration table;
receiving signals from the distributed sensor system;
comparing the signals received from the distributed sensor system to the limits defined by the sensor limits of the stored sensor configurations in the configuration table;
sending feedback instructions to the one or more of the power management component and the trusted element of the application processor based at least on comparing the signals received from the distributed sensor system with the stored sensor configurations in the configuration table;
comparing a sensor limit stored in the configuration table to a value stored in a register of a sensor of the distributed sensor system; and
sending instructions for a system shutdown to prevent a possible attack when the sensor limit in the configuration table and the value stored in the register of the sensor differ.

12. The method of claim 11 , wherein the distributed sensor system further includes a charging component, and wherein the method further comprises, with the feedback controller, sending a power management instruction to the power management component for controlling the charging component.

13. The method of claim 11 , wherein the distributed sensor system includes a plurality of thermal sensors and the stored sensor configurations include a temperature threshold for each of the plurality of thermal sensors, and wherein the signals received from the distributed sensor system include a signal from a first thermal sensor of the plurality of thermal sensors indicating that the temperature is above the temperature threshold for the first thermal sensor.

14. The method of claim 11 , further comprising determining that the updated sensor configurations are received in compliance with the selected security protocol based at least partially upon the updated sensor configurations being received within a predetermined time period of a reset or power event of the security component or the associated electronic device.

15. The method of claim 14 , further comprising determining that the updated sensor configurations are received in compliance with the selected security protocol based at least upon the updated sensor configurations being received from an authenticated device having a source identifier that has been authenticated using a cryptographic authentication and authorization protocol.

16. An electronic device comprising:
a distributed sensor system;
a power management component;
an application processor comprising a trusted element; and
a security component disposed communicatively between the distributed

Assignees

• Microsoft Technology Licensing Llc

Inventors

• Lunardhi Alfonsus D
• Mangipudi Kumar V K N

Classifications

• H04L63/10

  for controlling access to devices or network resources · CPC title

• H04L63/08

  for authentication of entities (cryptographic mechanisms or cryptographic arrangements for entity authentication H04L9/32) · CPC title

• H04L67/12

  specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks · CPC title

• H04L67/125

  involving control of end-device applications over a network · CPC title

• G08B29/18

  Prevention or correction of operating errors (G08B29/02, G08B29/12 take precedence) · CPC title