Overview
ISO/IEC 11889-3:2009 - "Information technology - Trusted Platform Module - Part 3: Structures" defines the data structures and constants used by the Trusted Platform Module (TPM). This part of the ISO/IEC 11889 family focuses on the binary formats, type definitions, tags and layout rules that enable TPM interoperability across hardware and software implementations. It establishes how TPM data must be represented so cryptographic and attestation operations preserve required security properties (confidentiality and integrity).
Key Topics
The standard provides precise definitions and constraints for TPM structures, including:
- Representation rules: endianness, byte packing, length fields and structure definitions.
- Basic types and tags: fundamental data types, Boolean types, helper redefinitions and vendor-specific ranges.
- Type enumerations and handles: algorithm IDs, resource/entity types, protocol IDs, startup types and reserved handle values.
- Core structures: versioning (TPM_STRUCT_VER, TPM_VERSION), digests, nonces, authdata and key handle lists.
- PCR and attestation: PCR selection/composite formats and PCR info structures used for platform integrity measurements.
- Key and storage formats: TPM_KEY complex, key parameters (RSA, symmetric), sealed and bound data structures.
- Identity and signed structures: endorsement key blobs, identity contents, certify/quote formats.
- NV storage and context blobs: non-volatile index formats, attributes and context save/restore structures.
- Transport, audit and delegate structures: transport wrappers, audit event formats and delegation tables.
- Management and capability areas: return codes, ordinals, capability areas and DAA (Direct Anonymous Attestation) structures.
- Deprecated items and normative language: clear use of MUST/SHOULD language and references to platform-specific requirements.
Applications
ISO/IEC 11889-3:2009 is practical for anyone implementing or integrating TPM functionality:
- TPM hardware and firmware designers - ensure the device produces/consumes canonical structures.
- TPM middleware and library developers - parse, serialize and validate TPM objects for OS and applications.
- OS vendors and hypervisors - implement attestation, secure storage and measured boot using correct formats.
- Security architects and integrators - validate interoperability and cryptographic assurances across platforms.
- Auditors and compliance teams - verify that TPM data handling meets standardized structure requirements.
Related Standards
Keywords: ISO/IEC 11889-3:2009, Trusted Platform Module, TPM structures, TPM data structures, TPM interoperability, TPM specification, PCR, TPM keys, NV storage.
