// When/Then
        assertThrows(IllegalArgumentException.class, () -> {
            transformHeader.setNonce(shortNonce);
        });

        assertThrows(IllegalArgumentException.class, () -> {
            transformHeader.setNonce(longNonce);
        });
    }

    @Test
    @DisplayName("Should handle null signature")
    void testNullSignature() {
        // When/Then

            final Smb2TransformHeader transformHeader = Smb2TransformHeader.decode(encryptedMessage, 0);
            final byte[] associatedData = transformHeader.getAssociatedData();
            byte[] nonce = transformHeader.getNonce();
            final byte[] authTag = transformHeader.getSignature();

            // Extract ciphertext
            final int ciphertextLength = encryptedMessage.length - Smb2TransformHeader.TRANSFORM_HEADER_SIZE;