Security Features

Secure Subsystem:
- Secure Subsytem with Advanced Crypto Engine (ACE) for execution of various cryptography commands
- Fast Crypto Engine for SHA-256, HMAC and AES-CMAC algorithms
- Physical Protection Security Measures, including voltage tampers, temperature tampers and active shield circuitry
- Sign/verify support:
  - ECDSA – P224, P256, P384 and 256-bit Brainpool elliptic curves
  - ECDSA – SECP256K1 (bitcoin/blockchain) curve
  - RSA 2048-bit signature generation and verification
  - RSA 3072-bit signature verification only
- ECDH/ECDHE/ECBD key agreement support:
  - Elliptic Curve Diffie-Hellman (ECDH) support for P224, P256, P384 and 256-bit Brainpool
  - Elliptic Curve Burmeiseter-Desmedt (ECBD) support for P224 curve
- Internal symmetric and asymmetric key generation and derivation:
  - P224, P256, P384 and 256-bit Brainpool
  - 2048-bit RSA keys
  - AES 16-byte keys
- AES and RSA encryption/decryption support:
  - AES ECB/GCM encryption/decryption supported directly
  - RSA 1024-bit and 2048-bit keys encryption/decryption support
- NIST SP800-90 A/B/C Random Number Generator (RNG)
- 16 MHz SPI interface to communicate security commands between the core and the Secure Subsystem
- Secure Subsystem’s authorization sessions can be used to prevent various kinds of attacks or denial of service
- Secure Subsystem’s Advanced Crypto Engine algorithms have achieved JIL HIGH rating and are certified by FIPS as per Cryptographic Algorithm Validation Program (CAVP)
- Secure Subsystem with FIPS 140-2 Level 2 with Physical Security Level 3 certification as per Cryptographic Module Validation Program (CMVP) [in progress]
Advanced Flash Security with CodeGuard™ Flash Security and Flash OTP:
- Secure Boot Segment (BS) with immutability:
  - CodeGuard Flash Security and Flash OTP by Write Inhibit facilitates realizing secure boot with immutability and external tools (Debugger/ICSP™) will not have access to read/write/erase the Boot Segment:
    - Optionally, as per user configuration, it is possible to allow an external tool to read the Flash content
  - User code in General Segment (GS) will not be capable of reading/writing/erasing code in Boot Segment (with high-security setting) via Run-Time Flash Programming/Reading:
    - Ensures integrity of the boot code
  - Code in Boot Segment cannot modify itself with high security and write protection enabled

Secure firmware upgrade with CodeGuard™
- CodeGuard provides protection for on-chip code Flash memory
- Provides an environment to support secure methods for transmitting and receiving data in the customer end product

Additional Security Features Include:
- Does not allow execution from RAM
- Restricts ICSP programming/erasing operations for all of Flash memory when Flash OTP by Write Inhibit is activated, and cannot be deactivated