1. SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
Thomas Ulz, Thomas Pieber, Christian Steger1
Christian Lesjak, Holger Bock, Rainer Matischek2
1Graz University of Technology, 2Infineon Austria AG

2. Outline Motivation, State-of-the-art SecureConfig
Requirements
QR-Code Protocol
NFC Protocol
Smart Sensor Enhancement
Evaluation
Conclusion and Future Work
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

3. Motivation – Industry 4.0
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

4. Motivation – Smart Homes
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

5. Motivation – Smart Sensor Configuration
Initial manufacturer keys
Initial configuration
Device owner key update
Specific configuration updates
Recurrent configuration updates
Reconfiguration for changing tasks
Reconfiguration for resale
Deletion of confidential data
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

6. State-of-the-art Various configuration interfaces
Wired
Wireless (WiFi, Bluetooth, …)
Buttons, Displays, DIP Switches
Using Near Field Communication (NFC)
Wu et al. 2016
Firmware Updates, not secured
Haase et al. 2016
Arbitrary Data, some security
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

7. Outline Motivation, State-of-the-art SecureConfig
Requirements
QR-Code Protocol
NFC Protocol
Smart Sensor Enhancement
Evaluation
Conclusion and Future Work
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

8. Configuration Interface Requirements
Do not expose configuration interface to network
Use NFC
Suggested by Wu et al. 2016, Haase et al. 2016
Suitable for smart home and smart factory
Not considered in State-of-the-art
NFC Reader for Smart Home users infeasible
Secured confidential configurations
State-of-the-art not or insufficiently secured
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

9. Configuration Interface Requirements
Configure devices with no power source attached
Prevent tampering with applied configurations
Our contribution:
Approach that meets these requirements
Comprising of protocol and hardware extension
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

10. Hybrid Approach
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

11. QR-Code Protocol
Two variants, both encrypt payload using Authenticated Encryption (AE)
Inline, no connection to backend required
Up to 2900 bytes of data directly in QR-Code
URL, requires connection to backend
QR-Code contains URL to download configuration
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

12. NFC Protocol Based on the NFC Data Exchange Format (NDEF)
Accept Configuration if AE verified and:
Version > current version
Realtime < Validity
Sensor ID matches
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

13. Outline Motivation, State-of-the-art SecureConfig
Requirements
QR-Code Protocol
NFC Protocol
Smart Sensor Enhancement
Evaluation
Conclusion and Future Work
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

14. Smart Sensor Enhancement
Requirements
Suitable for new and legacy devices
Tamper resistant
NFC Interface
Networking Interface
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

15. Smart Sensor Enhancement
Requirements
Suitable for new and legacy devices
Tamper resistant
NFC Interface
Networking Interface
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

16. Outline Motivation, State-of-the-art SecureConfig
Requirements
QR-Code Protocol
NFC Protocol
Smart Sensor Enhancement
Evaluation
Conclusion and Future Work
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

17. Evaluation Feasibility: Prototype
Performance: overhead, transfer speed
Security improvements: threat analysis
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

18. Evaluation – Prototype
Built using COTS
Sensor Controller
Infineon XMC4500
Security Controller (SC)
Infineon SLE78
Android phone as mobile device
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

19. Evaluation – Performance
Small configuration update of 64 bytes
200ms, similar to TLS handshake
Overhead
16 Bytes fixed
+ variable overhead
Padding
Length of MAC
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

20. Evaluation – Threat Analysis
Not exhaustive, most relevant threats identified
2 Assets, 11 threats
Countermeasures for 9 threats
Residual risks for 2 threats
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

21. Evaluation – Threat Analysis
Problems such as weak cryptography, bugs in configuration interface or backdoors
Mitigated by using CC EAL5+ certified SC
Problems with malicious users and adversaries
Mitigated by proposed configuration protocol
Residual risks for DoS attacks by malicious users
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

22. Outline Motivation, State-of-the-art SecureConfig
Requirements
QR-Code Protocol
NFC Protocol
Smart Sensor Enhancement
Evaluation
Conclusion and Future Work
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

23. Conclusion and Future Work
QR-Code and NFC Hybrid Configuration Approach
Suitable for smart home and smart factory use cases
Secured by protocol and tamper resistant hardware
Relevant threats mitigated; Acceptable overhead
Future work: SPAKE, attestation mechanism
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th

24. Thank you for your attention!
Questions?
Thank you for your attention!
Acknowledgement:
SecureConfig: NFC and QR-Code based Hybrid Approach for Smart Sensor Configuration
IEEE RFID 2017, May 10th