PSA Certified
Attestation API 1.0

Document number:	IHI 0085
Release Quality:	Final
Issue Number:	4
Confidentiality:	Non-confidential
Date of Issue:	23/09/2025

Contents

• About this document
  • Release information
  • License
  • References
  • Terms and abbreviations
  • Potential for change
  • Conventions
  • Current status and anticipated changes
  • Feedback

• 1 Introduction
  • 1.1 About Platform Security Architecture
  • 1.2 About the Attestation API
• 2 Use cases and rationale
  • 2.1 Device enrolment
  • 2.2 Identifying certification
  • 2.3 Integrity reporting
• 3 Initial Attestation report
  • 3.1 Information model
    • 3.1.1 Software components
  • 3.2 Report format and signing
    • 3.2.1 Token encoding
    • 3.2.2 Signing
    • 3.2.3 EAT standard claims
    • 3.2.4 EAT custom claims
• 4 API reference
  • 4.1 API conventions
  • 4.2 Status codes
  • 4.3 General definitions
    • 4.3.1 PSA_INITIAL_ATTEST_API_VERSION_MAJOR (macro)
    • 4.3.2 PSA_INITIAL_ATTEST_API_VERSION_MINOR (macro)
    • 4.3.3 PSA_INITIAL_ATTEST_MAX_TOKEN_SIZE (macro)
  • 4.4 Challenge sizes
    • 4.4.1 PSA_INITIAL_ATTEST_CHALLENGE_SIZE_32 (macro)
    • 4.4.2 PSA_INITIAL_ATTEST_CHALLENGE_SIZE_48 (macro)
    • 4.4.3 PSA_INITIAL_ATTEST_CHALLENGE_SIZE_64 (macro)
  • 4.5 Attestation
    • 4.5.1 psa_initial_attest_get_token (function)
    • 4.5.2 psa_initial_attest_get_token_size (function)

• A Example header file
  • A.1 psa/inital_attestation.h
• B Example report
• C CDDL
• D Document history