Correct fwTPM hierarchy and NV behavior and clear TPM command secrets

[aidangarske]

F-14405, F-14406, F-14430, F-14431, F-14230, F-14439

[aidangarske]

@wolfSSL-Fenrir-bot review balanced

[Copilot]

Copilot review overview

🟡 Changes recommended

Unresolved NV lifecycle and command-buffer wiping issues remain.

Review effort: Lite
Findings: 2

Open (2)

• Preserve pre-write locks unless WRITE_STCLEAR is set · New
• Wipe request payload before returning transport errors · New

What changed in this PR

Corrects fwTPM hierarchy/NV behavior and strengthens TPM command-buffer secret cleanup.

Changes:

• Adds versioned endorsement-proof derivation and legacy compatibility.
• Updates hierarchy, Clear, Startup, and NV lifecycle handling.
• Adds command-buffer cleanup and regression tests.

File	Summary
wolftpm/​fwtpm/​fwtpm.h	Adds proof-version state.
wolftpm/​fwtpm/​fwtpm_crypto.h	Updates crypto helper APIs.
tests/​unit_tests.c	Adds command-buffer wipe tests.
tests/​fwtpm_unit_tests.c	Adds hierarchy and NV regression tests.
src/​tpm2.c	Cleans command buffers after responses and errors.
src/​fwtpm/​fwtpm.c	Initializes proof-version state.
src/​fwtpm/​fwtpm_nv.c	Persists proof-version state.
src/​fwtpm/​fwtpm_crypto.c	Updates proof and private-blob derivation.
src/​fwtpm/​fwtpm_command.c	Updates Clear, Startup, NV, and hierarchy handling.

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[wolfSSL-Fenrir-bot]

Fenrir Automated Review — PR #613

Scan targets checked: wolftpm-src, wolftpm-bugs
Coverage: 7 of 9 in-scope changed file(s) opened by the reviewer; not opened: wolftpm/fwtpm/fwtpm.h, wolftpm/fwtpm/fwtpm_crypto.h

Findings: 2
2 finding(s) posted as inline comments (see file-level comments below)

This review was generated automatically by Fenrir. Reported findings require changes before merge.

Review tier: Balanced

[wolfSSL-Fenrir-bot]

Fenrir Automated Review — PR #613

Scan targets checked: wolftpm-src, wolftpm-bugs
Coverage: 1 of 1 in-scope changed file(s) opened by the reviewer

Fenrir result: Approved ✅

No new issues found in the changed files.

Advisory only — this automated result does not count as a GitHub approval.

Review tier: Lite

Fenrir's latest completed scan found no issues; clearing the prior automated change request.

[Copilot]

Copilot review overview

🔵 Needs a closer look

Unresolved NV startup-state handling and command-buffer cleanup gaps remain.

Review effort: Lite
Findings: None

Resolved since last review (2)

• Wipe request payload before returning transport errors
• Preserve pre-write locks unless WRITE_STCLEAR is set

Previously missed (2)

In code that hasn't changed since last review

NV clear fails to erase stored data on Startup(CLEAR)

src/​fwtpm/​fwtpm_command.c:1078

[Medium, CWE-200] TPMA_NV_CLEAR_STCLEAR means the NV contents are cleared on Startup(CLEAR), but this branch only clears WRITTEN and the separate written flag. A subsequent partial write can make the index readable again while exposing untouched bytes from before the clear. Clear the stored data as part of this transition and preserve it in the existing rollback path if persistence fails.

Retry path leaves command secrets after transport failure

src/​tpm2.c:653

[Medium, CWE-316] The retry-enabled variant has the same gap: a transport/SPDM failure returns at lines 629-631 before this final-attempt wipe, leaving the serialized command and its auth/plaintext parameters in the shared buffer. Wipe the command body on that early return too.