[dgarske]

wolfTPM2_UnloadHandles_AllTransient() flushed 0x80000000 to 0x80000002 blindly. With nothing loaded each flush returns TPM_RC_HANDLE, which DEBUG_WOLFTPM prints at the start of wrap_test on real hardware as if the transport had failed. It also never reached past three handles.

The wrapper now queries TPM_CAP_HANDLES from TRANSIENT_FIRST, following continuation pages, and flushes exactly the handles reported. If the first query fails it still tries the fixed range. A failed query or flush is now returned to the caller, where this API previously always returned success.

• src/tpm2_wrap.c, wolftpm/tpm2_wrap.h: the change and its doc note.
• examples/pqc/pqc_ctrl.c: use the wrapper instead of a local copy of the same query.
• tests/unit_tests.c: load a transient SRK, flush, confirm none remain.
• tests/transient_unload_tests.c: scripted TPM_CAP_HANDLES pages for continuation and the failure paths, which a simulator cannot produce on demand.

Tested with make check against the fwTPM and ibmswtpm2 simulators.

[Copilot]

🟡 Changes recommended

Handle cleanup stops after the first capability page and accepts non-transient handles that can clear session configuration, while its test fails on RSA-only TPMs.

3 open issues

• Reject non-transient handles before unloading · New
• Flush all capability pages before reporting success · New
• Choose SRK algorithm based on TPM capabilities · New

What changed in this PR

This PR changes wolfTPM’s transient-handle cleanup to query loaded handles instead of blindly flushing three fixed slots, reducing misleading debug errors when no objects are loaded.

Changes:

• Query TPM_CAP_HANDLES before flushing, retaining the fixed-range fallback if the query fails.
• Replace the PQC example’s local cleanup helper with the shared wrapper.
• Document the behavior and add a unit test covering transient-object cleanup.

File	Description
wolftpm/​tpm2_wrap.h	Documents capability-based cleanup and fallback behavior.
tests/​unit_tests.c	Adds a test that creates an SRK and verifies transient handles are unloaded.
src/​tpm2_wrap.c	Implements capability-based transient-handle cleanup.
examples/​pqc/​pqc_ctrl.c	Reuses the wrapper instead of a local cleanup implementation.

_{Review effort: Balanced}

[embhorn]

Skoll Code Review

Scan type: review

Overall recommendation: REQUEST_CHANGES
Findings: 3 total — 3 posted, 0 skipped
3 finding(s) posted as inline comments (see file-level comments below)

Posted findings

• [High] Advance the cursor from the reported handle — src/tpm2_wrap.c:9488
• [High] Preserve failure reporting for the flush command — examples/pqc/pqc_ctrl.c:690
• [Medium] Exercise continuation in the new test — tests/unit_tests.c:1889-1891

Review generated by Skoll

[embhorn]

Skoll Code Review

Scan type: review

Overall recommendation: APPROVE
Findings: 0 total — 0 posted, 0 skipped

No issues found.

Review generated by Skoll