SLAAE29 January   2023 MSPM0G1105 , MSPM0G1106 , MSPM0G1107 , MSPM0G1505 , MSPM0G1506 , MSPM0G1507 , MSPM0G3105 , MSPM0G3106 , MSPM0G3107 , MSPM0G3505 , MSPM0G3506 , MSPM0G3507 , MSPM0L1105 , MSPM0L1106 , MSPM0L1303 , MSPM0L1304 , MSPM0L1304-Q1 , MSPM0L1305 , MSPM0L1305-Q1 , MSPM0L1306 , MSPM0L1306-Q1 , MSPM0L1343 , MSPM0L1344 , MSPM0L1345 , MSPM0L1346

 

  1.   Abstract
  2.   Trademarks
  3. 1Introduction
    1. 1.1 Goals of Cybersecurity
    2. 1.2 Platform Security Enablers
  4. 2Device Security Model
    1. 2.1 Initial Conditions at Boot
    2. 2.2 Boot Configuration Routine (BCR)
    3. 2.3 Bootstrap Loader (BSL)
    4. 2.4 Boot Flow
    5. 2.5 User-Specified Security Policies
      1. 2.5.1 Boot Configuration Routine (BCR) Security Policies
        1. 2.5.1.1 Serial Wire Debug Related Policies
          1. 2.5.1.1.1 SWD Security Level 0
          2. 2.5.1.1.2 SWD Security Level 1
          3. 2.5.1.1.3 SWD Security Level 2
        2. 2.5.1.2 Bootstrap Loader (BSL) Enable/Disable Policy
        3. 2.5.1.3 Flash Memory Protection and Integrity Related Policies
          1. 2.5.1.3.1 Locking the Application (MAIN) Flash Memory
          2. 2.5.1.3.2 Locking the Configuration (NONMAIN) Flash Memory
          3. 2.5.1.3.3 Verifying Integrity of Application (MAIN) Flash Memory
      2. 2.5.2 Bootstrap Loader (BSL) Security Policies
        1. 2.5.2.1 BSL Access Password
        2. 2.5.2.2 BSL Read-out Policy
        3. 2.5.2.3 BSL Security Alert Policy
      3. 2.5.3 Configuration Data Error Resistance
        1. 2.5.3.1 CRC-Backed Configuration Data
        2. 2.5.3.2 16-bit Pattern Match for Critical Fields
  5. 3Secure Boot
    1. 3.1 Secure Boot Authentication Flow
    2. 3.2 Asymmetric vs. Symmetric Secure Boot
  6. 4Cryptographic Acceleration
    1. 4.1 Hardware AES Acceleration
      1. 4.1.1 Overview
      2. 4.1.2 AES Performance
    2. 4.2 Hardware True Random Number Generator (TRNG)
  7. 5Device Identity
  8. 6Summary
  9. 7References
  10. 8Revision History
  11.   A Security Enablers by Subfamily

2.5.3.2 16-bit Pattern Match for Critical Fields

Critical policies in the BCR configuration memory, such as the SWD security policies, are implemented as 16-bit pattern-match fields in the NONMAIN memory, with the following characteristics:

  • An exact pattern match is required to enable lower security states
  • Any value in the 16-bit field not matching the exact defined patterns results in a maximally secure state for the respective parameter

This behavior prevents single bit flips from causing the device to enter a lower security state than that which was originally specified.