Fix ArrayIndexOutOfBoundsException in AES-GCM/CCM, correct CCM arg sanitization

[cconlon]

The SunJCE test crypto/provider/Cipher/AEAD/ReadWriteSkip.java was failing when run with wolfJCE as the provider, throwing: ArrayIndexOutOfBoundsException: arraycopy: source index -16 out of bounds for byte[0]. This also fixes SunJCE test: crypto/provider/Cipher/AEAD/GCMBufferTest.java.

This occurred when processing zero-length plaintext in AES-GCM/CCM modes where the input consists only of the authentication tag (16 bytes).

This PR adds bounds checking before tag extraction in both AES-GCM and AES-CCM decrypt paths, validates that input length is at least equal to tag length, and throws appropriate AEADBadTagException if input is too short.

JUnit test is included for regression prevention.

[Copilot]

Pull Request Overview

This PR fixes an ArrayIndexOutOfBoundsException in AES-GCM/CCM modes when processing zero-length plaintext with authentication tags. The fix adds proper bounds checking before tag extraction and validates input length requirements.

• Added bounds checking in WolfCryptCipher.java to prevent ArrayIndexOutOfBoundsException when input is shorter than tag length
• Updated CCM argument validation in JNI layer to properly handle null input when length is zero
• Modified existing tests to reflect that null input with valid AAD should succeed rather than fail

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
src/main/java/com/wolfssl/provider/jce/WolfCryptCipher.java	Added input length validation before tag extraction in GCM/CCM decrypt paths
jni/jni_aesccm.c	Updated argument validation to allow null input when length is zero and added proper parameter bounds checking
src/test/java/com/wolfssl/wolfcrypt/test/AesCcmTest.java	Updated test expectations to reflect that null input with AAD should succeed
src/test/java/com/wolfssl/provider/jce/test/WolfCryptCipherTest.java	Added comprehensive regression test for zero-length plaintext in AES-GCM/CCM modes

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