SWRA846 July   2025 CC2642R-Q1

 

  1.   1
  2.   Abstract
  3. 1Analysis of Bluetooth Pairing Technology Principles
    1. 1.1 LE Legacy Pairing and LE Secure Connections Pairing
    2. 1.2 Analysis of Association Mode Security Characteristics
    3. 1.3 Privacy Protection and Address Management
  4. 2Common Issues in Pairing Encryption
    1. 2.1 Integrity Check Fault—MIC Verification Failure (MIC failure)
    2. 2.2 Abnormal Key Negotiation—DHKey Verification Failure (DHKey check fail)
    3. 2.3 Key Management Defect—PIN/Key Loss (PIN or Key missing)
      1. 2.3.1 Key Missing During Pairing Phase
      2. 2.3.2 LTK Missing During Encryption Phase
  5. 3A Solution for Encryption Resource Conflicts
    1. 3.1 Environment Selection and Configuration
    2. 3.2 Implementing AES-256 Encryption and Decryption Using TinyAES Library
    3. 3.3 System-Level Optimization Exploration
      1. 3.3.1 Memory Allocation Inspection
      2. 3.3.2 Padding Processing and Thread Safety
  6. 4Conclusion
  7. 5References

1.1 LE Legacy Pairing and LE Secure Connections Pairing

Two main technical implementation paths currently exist in the Bluetooth protocol stack: LE Legacy pairing, introduced as a foundational security scheme in the Bluetooth Core Specification v4.0, protects data through a Short Term Key (STK) generation mechanism; while LE Secure Connections, introduced as a security scheme in the Bluetooth Core Specification v4.2, is based on a more advanced Elliptic Curve Diffie-Hellman (ECDH) algorithm to provide stronger resistance against man-in-the-middle attacks during key negotiation, marking a significant evolution of the Bluetooth security architecture from traditional symmetric encryption to an asymmetric cryptographic framework. For more details, please refer to the Bluetooth Core Specification and the TI BLE5-Stack User's Guide (GAP Bond Manager and LE Secure Connections sections).