java - mKeyStore?.getKey ("default_key", null) 在 Kotlin 中获取 null

Question

我在 Android 中尝试过指纹 validator 。最初它是可以工作的，而且是在 Java 中。我现在正在将代码移植到 kotlin。这次有些东西对我不起作用。

try {
        mKeyStore = KeyStore.getInstance("AndroidKeyStore");
    } catch (KeyStoreException e) {
        throw new RuntimeException("Failed to get an instance of KeyStore", e);
    }
    try {
        mKeyGenerator = KeyGenerator
                .getInstance(KeyProperties.KEY_ALGORITHM_AES, "AndroidKeyStore");
    } catch (NoSuchAlgorithmException | NoSuchProviderException e) {
        throw new RuntimeException("Failed to get an instance of KeyGenerator", e);
    }    

mKeyStore.load(null);
SecretKey key = (SecretKey) mKeyStore.getKey("default_key", null);

上面写的代码是用Java编写的，我得到的键是非空值。

但是当用 Kotlin 编写相同的代码时，关键是获取 null 值。

try {
    mKeyStore = KeyStore.getInstance("AndroidKeyStore")
} catch (e: KeyStoreException) {
    throw RuntimeException("Failed to get an instance of KeyStore", e)
}

try {
    mKeyGenerator = KeyGenerator
        .getInstance(KeyProperties.KEY_ALGORITHM_AES, "AndroidKeyStore")
} catch (e: NoSuchAlgorithmException) {
    throw RuntimeException("Failed to get an instance of KeyGenerator", e)
} catch (e: NoSuchProviderException) {
    throw RuntimeException("Failed to get an instance of KeyGenerator", e)
}

mKeyStore?.load(null)
val key = mKeyStore?.getKey("default_key", null) as? SecretKey

为什么我会收到这个？如果有什么遗漏请澄清。

感谢您抽出宝贵的时间。

Answer 1

初始化 key 生成器，然后提取 key 。

 mKeyGenerator.init(
        KeyGenParameterSpec.Builder("default_key", KeyProperties.PURPOSE_ENCRYPT or KeyProperties.PURPOSE_DECRYPT)
            .setBlockModes(KeyProperties.BLOCK_MODE_CBC)
            .setUserAuthenticationRequired(true)
            .setEncryptionPaddings(
                KeyProperties.ENCRYPTION_PADDING_PKCS7
            )
            .build()
    )
    mKeyGenerator.generateKey()