Fix global ref lifecycle for verify and missing-CRL callbacks

[cconlon]

This PR fixes a JNI callback global reference lifecycle bug where setVerify() / setCRLCb() on one WolfSSLContext or WolfSSLSession could delete a still-live callback reference held by another instance.

• Moves per-context verify callback jobject from a process-wide static to per-WOLFSSL_CTX ex_data, allocated in Java_com_wolfssl_WolfSSL_init() after wolfSSL_Init().
• NativeVerifyCallback() now resolves the callback via store -> ssl -> ctx -> ex_data, so each context fires its own user callback.
• Keeps CTX-level and session-level missing-CRL callback refs as process-globals (wolfSSL CbMissingCRL has no SSL/CTX argument), but stops deleting them in freeContext() / freeSSL(). Only setCRLCb() overwrites and JNI_OnUnload() release them.
• Adds NativeWolfSSLContextCleanup() / NativeWolfSSLSessionCleanup() helpers called from JNI_OnUnload() for library-level cleanup of globals.
• Adds test_WolfSSLContext_setVerifyMultipleContexts() exercising the multi-context install / replace / unregister / interleaved-free lifecycle.

Fixes F-1024.

[Copilot]

Pull request overview

Note

Copilot was unable to run its full agentic suite in this review.

Fixes JNI global-ref lifecycle issues by making the verify callback reference per-WOLFSSL_CTX (via ex_data) and adjusting missing-CRL callback cleanup to only happen at library unload.

Changes:

• Store per-context verify callback jobject in WOLFSSL_CTX ex_data and resolve it in NativeVerifyCallback().
• Move missing-CRL callback global-ref cleanup to JNI_OnUnload() via new cleanup helpers.
• Add a JUnit test covering multi-context setVerify() install/replace/unregister/free flows.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
src/test/com/wolfssl/test/WolfSSLContextTest.java	Adds a multi-context setVerify() lifecycle test intended to surface global-ref mishandling.
native/com_wolfssl_globals.h	Declares the ex_data index global and new cleanup helper prototypes.
native/com_wolfssl_WolfSSLSession.c	Adds JNI_OnUnload() cleanup for the process-global session missing-CRL callback; stops freeing it in freeSSL().
native/com_wolfssl_WolfSSLContext.c	Moves verify callback storage to per-CTX ex_data, adds CTX-level missing-CRL cleanup helper, and adjusts freeContext() cleanup.
native/com_wolfssl_WolfSSL.c	Allocates the ex_data index during WolfSSL_init() and calls cleanup helpers in JNI_OnUnload().

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[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 5 comments.

[wolfSSL-Fenrir-bot]

Fenrir Automated Review — PR #369

Scan targets checked: wolfssljni-bugs, wolfssljni-src

No new issues found in the changed files. ✅