Project Structure

Project Structure

Top-level layout

Path	Purpose
src/	Core protocol, crypto glue, transcript, secured messaging, session logic, and TPM/TCG side
src/vendor/	Nuvoton and Nations TPM-specific vendor commands
wolfspdm/	Public headers
examples/	Demo client and emulator integration script
test/	Unit tests and test certificate data
docs/	Project documentation (this wiki, mirrored under docs/)
.github/workflows/	CI workflows

Core source modules

File	Responsibility
src/spdm_context.c	Context init/free lifecycle and state setup
src/spdm_msg.c	SPDM message construction, parsing, and signature verification helpers
src/spdm_crypto.c	Cryptographic helper operations (ECDSA/ML-DSA verify, hashing)
src/spdm_kdf.c	HKDF-based key derivation
src/spdm_transcript.c	Transcript management (TH computations)
src/spdm_secured.c	Secured message protection (AES-256-GCM), app data (SendData/ReceiveData/Encrypt/DecryptMessage)
src/spdm_session.c	Handshake exchange helper, KeyExchange/Finish, Heartbeat, KeyUpdate
src/spdm_internal.h	Internal types, constants, and internal APIs shared across src/

Standard (certificate) requester modules: built with BUILD_CERT

Compiled when the standard requester is enabled (--disable-cert removes these; requires WOLFSPDM_NO_CERT not set):

File	Responsibility
src/spdm_standard.c	GET_CAPABILITIES/NEGOTIATE_ALGORITHMS/GET_DIGESTS/GET_CERTIFICATE, certificate-chain validation, trust anchor configuration, Connect
src/spdm_attest.c	GET_MEASUREMENTS and CHALLENGE, L1/L2 and M1 running transcript hashes
src/spdm_chunk.c	CHUNK_SEND/CHUNK_GET large-message chunking engine

TPM/TCG side modules

File	Built with	Responsibility
src/spdm_tcg.c	--enable-tcg (BUILD_TCG)	TCG SPDM binding message framing, vendor-command helpers, identity-key exchange, ConnectTCG
src/spdm_psk.c	--enable-psk (BUILD_PSK)	PSK_EXCHANGE/PSK_FINISH, PSK key derivation, ConnectPsk
src/vendor/spdm_nuvoton.c	--enable-nuvoton (BUILD_NUVOTON)	Nuvoton NPCT75x status/lock vendor commands
src/vendor/spdm_nations.c	--enable-nations (BUILD_NATIONS)	Nations NS350 status/lock/PSK-provisioning vendor commands
src/spdm_responder.c	--enable-responder (BUILD_RESPONDER)	SPDM responder: answers requester-driven messages over the TCG binding, TPM command tunneling

Public API surface

Header	Content
wolfspdm/spdm.h	Main public API, WOLFSPDM_MODE, feature macros (WOLFSPDM_HAS_*)
wolfspdm/spdm_types.h	SPDM protocol constants, algorithm identifiers, build-switch implications
wolfspdm/spdm_error.h	Error code enum and error-string helper
wolfspdm/spdm_tcg.h	TCG SPDM binding framing, vendor-command codes and helpers
wolfspdm/spdm_nuvoton.h	Nuvoton-specific status API
wolfspdm/spdm_nations.h	Nations-specific status/PSK-provisioning API
wolfspdm/spdm_psk.h	Shared PSK protocol API
wolfspdm/spdm_responder.h	SPDM responder API
wolfspdm/options.h	Auto-generated from config.h at build time

Build/test assets

File	Purpose
configure.ac	Autotools configure logic and options
Makefile.am	Library, test, and example build targets
examples/spdm_demo.c	CLI demo: session, measurements, challenge, heartbeat, key update, app data, version and key-exchange selection
examples/spdm_test.sh	21-test emulator integration driver (7 scenarios x SPDM 1.2/1.3/1.4)
test/unit_test.c	Unit test coverage
test/test_certs.h	Classical (ECDSA P-384) test certificate chains
test/test_certs_mldsa.h	ML-DSA test certificate chains