Bound TPM2 response decrypt-parameter size, zeroize primary-key auth, and expand marshalling/import test coverage

[aidangarske]

F-7011, F-7014, F-7017, F-7018, F-7019, F-7020

[Copilot]

Pull request overview

This PR hardens wolfTPM’s response-processing and auth-handling paths against attacker-controlled TPM/transport inputs, and expands unit-test coverage for marshalling/import boundary cases.

Changes:

• Add bounds enforcement so response parameter decryption cannot write past the declared parameter area (TPM2_ResponseProcess).
• Zeroize duplicated primary-key auth material after wolfTPM2_CreatePrimaryKey_ex returns (wolfTPM2_CreatePrimaryKey).
• Expand unit tests for decrypt-parameter size overflow, signature/public marshalling roundtrips, and RSA/ECC import seed boundary checks.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
tests/unit_tests.c	Adds regression/coverage tests for response decrypt sizing, signature/public marshalling, and import bounds.
src/tpm2.c	Adds bounds checking for response decrypt region sizing in TPM2_ResponseProcess.
src/tpm2_wrap.c	Zeroizes the local primary-key struct copy to scrub duplicated auth data.
src/fwtpm/fwtpm_command.c	Switches PolicyPassword plaintext auth comparison to a fixed-trip-count constant-time helper.