Require verify result to be captured in client cert response handlers

[padelsbach]

Addresses F-6199. Caller is no longer allowed to pass out_rc == NULL since this value contains the actual verification result. This breaks convention within wolfHSM, admittedly.

[Copilot]

Pull request overview

This PR enforces that certificate verification APIs always capture the server’s verification verdict by making out_rc mandatory (non-NULL) across client-side cert verify response handlers and synchronous helpers, addressing F-6199.

Changes:

• Updated public API documentation in wh_client.h to state out_rc is required and to clarify that rc == 0 does not imply a successful verification verdict.
• Added argument validation in client cert verification code paths to reject out_rc == NULL with WH_ERROR_BADARGS.
• Extended certificate client tests to ensure passing a NULL verdict pointer is rejected.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
wolfhsm/wh_client.h	Updates API docs to require out_rc and clarify verification semantics.
src/wh_client_cert.c	Enforces out_rc non-NULL in cert verify response/dispatch helpers.
test/wh_test_cert.c	Adds regression coverage for rejecting out_rc == NULL in cert verify.

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[bigbrett]

@padelsbach can we get rid of these comments in whatever PR you are working on next? Kinda just clutters things and unneccessary. But dont want to block this merge

[padelsbach]

For future reference, the removal of these are in #430

[wolfSSL-Fenrir-bot]

Fenrir Automated Review — PR #426

Scan targets checked: wolfhsm-core-bugs, wolfhsm-crypto-bugs, wolfhsm-src
Findings: 1

Info (1)

Inner out_rc != NULL guards are now always-true dead conditions

File: src/wh_client_cert.c:431
Function: _certVerifyResponse
Category: Dead/unreachable code

The new top-level out_rc == NULL early return makes the pre-existing inner if (out_rc != NULL) guards unreachable when false in the response helpers (_certVerifyResponse, _certVerifyMultiRootResponse, _certVerifyDmaResponse, _certVerifyMultiRootDmaResponse, and the Acert responders). Harmless but now-redundant.

Recommendation: Optionally drop the now-redundant inner NULL guard around the *out_rc = resp.rc assignment.

Referenced code: src/wh_client_cert.c:431-433 (3 lines)

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This review was generated automatically by Fenrir. Findings are non-blocking.