Fixes from static analyzer

[danielinux]

• 20d9e39 F/011 Guard NULL in psa_key_derivation_get_capacity
• b04e6c3 F/003 Reject AES keys for ChaCha20-Poly1305
• 04f5550 F/014 Fix EdDSA length handling on 64-bit
• e9b00d2 F/009 Fix LMS and XMSS output lengths on 64-bit
• 44005a6 F/001 Zeroize AEAD keys before free
• 8cf6e69 F/002 Zeroize KDF secret buffers before free
• 7d6b0ac F/007 Guard AEAD buffer growth overflow
• 3f80c28 F/008 Guard KDF buffer growth overflow
• 8070a3a F/013 Free volatile key data on export rejection
• 003627c F/015 Fix PQ key-type switch fallthrough
• b964bd9 F/012 Fix RSA-PSS MGF and verify handling
• 8e947b8 F/004 Use constant-time compare for MAC verify
• a826de8 F/005 Use constant-time compare for KDF verify
• d500173 F/006 Use constant-time compare for RSA verify
• b720999 F/010 Use constant-time compare for hash verify
• ba7aea9 F/016 Use Dilithium export APIs for ML-DSA keys

[Copilot]

Pull request overview

Addresses a set of static-analyzer findings across the wolfPSA PSA engine implementation, focusing on correctness on 64-bit platforms, constant-time verification, buffer overflow/zeroization hardening, and added regression tests.

Changes:

• Harden crypto verification and secret handling (constant-time compares, key/secret zeroization, overflow guards).
• Fix algorithm/key-type correctness and size/length handling (RSA-PSS MGF/padding, AEAD key-type checks, EdDSA/LMS/XMSS 64-bit length fixes, PQ key-type switch fix).
• Add/extend PSA server tests, including a new RSA-PSS interop test and additional negative/regression cases.

Reviewed changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
test/psa_server/psa_rsa_pss_interop_test.c	New RSA-PSS interop/regression test between PSA and wolfCrypt.
test/psa_server/psa_api_test.c	Adds skipped-test reporting and new regression tests (ChaCha20/AES key rejection, Ed25519 signature length, KDF NULL capacity).
test/Makefile	Builds and links the new RSA-PSS interop test binary.
src/psa_rsa.c	Fixes RSA-PSS MGF selection and verification flow; switches to constant-time compare for PKCS#1 v1.5 path.
src/psa_pq.c	Fixes key-type support/size checks for LMS/XMSS to return success instead of falling through.
src/psa_mldsa.c	Exports ML-DSA keys via Dilithium export APIs (instead of copying internal buffers).
src/psa_mac.c	Switches MAC verification to constant-time compare.
src/psa_lms_xmss.c	Fixes 64-bit length handling by avoiding size_t* → word32* casts.
src/psa_key_storage.c	Frees volatile key material when public-key export rejects unsupported types.
src/psa_key_derivation.c	Adds NULL guard, overflow guard, buffer zeroization, and constant-time compare for derivation verification.
src/psa_hash_engine.c	Switches hash verification/compare to constant-time compare.
src/psa_ed25519_ed448.c	Fixes Ed25519/Ed448 length handling by avoiding size_t* → word32* casts.
src/psa_aead.c	Adds overflow guard and key zeroization; tightens ChaCha20-Poly1305 key-type checks.

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[danielinux]

All comments addressed