使用指纹传感器作为生物识别

use finger print sensor as bio metric

我是 android 生物识别集成的新手。

是否可以将 android 设备屏幕或指纹传感器用作生物识别设备,以便用户无需使用任何电子邮件或密码即可登录应用程序。

and this and this 作为参考。

使用外部指纹扫描仪或生物识别是唯一的选择还是有替代解决方案?

这是我用作参考的代码。请看一下,让我知道如何获取用户指纹。

MainActivity extends AppCompatActivity {

private FingerprintManager fingerprintManager;
private KeyguardManager keyguardManager;
private KeyStore keyStore;
private KeyGenerator keyGenerator;
private static final String KEY_NAME = "example_key";
private Cipher cipher;
private FingerprintManager.CryptoObject cryptoObject;

@TargetApi(Build.VERSION_CODES.M)
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    keyguardManager =
            (KeyguardManager) getSystemService(KEYGUARD_SERVICE);
    fingerprintManager =
            (FingerprintManager) getSystemService(FINGERPRINT_SERVICE);


    if (!keyguardManager.isKeyguardSecure()) {

        Toast.makeText(this,
                "Lock screen security not enabled in Settings",
                Toast.LENGTH_LONG).show();
        return;
    }

    if (ActivityCompat.checkSelfPermission(this,
            Manifest.permission.USE_FINGERPRINT) !=
            PackageManager.PERMISSION_GRANTED) {
        Toast.makeText(this,
                "Fingerprint authentication permission not enabled",
                Toast.LENGTH_LONG).show();

        return;
    }

    if (!fingerprintManager.hasEnrolledFingerprints()) {

        // This happens when no fingerprints are registered.
        Toast.makeText(this,
                "Register at least one fingerprint in Settings",
                Toast.LENGTH_LONG).show();
        return;
    }

    if (!fingerprintManager.hasEnrolledFingerprints()) {

        // This happens when no fingerprints are registered.
        Toast.makeText(this,
                "Register at least one fingerprint in Settings",
                Toast.LENGTH_LONG).show();
        return;
    }

    generateKey();

    if (cipherInit()) {
        cryptoObject =
                new FingerprintManager.CryptoObject(cipher);
        FingerprintHandler helper = new FingerprintHandler(this);
        helper.startAuth(fingerprintManager, cryptoObject);
    }

}

@TargetApi(Build.VERSION_CODES.M)
protected void generateKey() {
    try {
        keyStore = KeyStore.getInstance("AndroidKeyStore");
    } catch (Exception e) {
        e.printStackTrace();
    }

    try {
        keyGenerator = KeyGenerator.getInstance(
                KeyProperties.KEY_ALGORITHM_AES,
                "AndroidKeyStore");
    } catch (NoSuchAlgorithmException |
            NoSuchProviderException e) {
        throw new RuntimeException(
                "Failed to get KeyGenerator instance", e);
    }

    try {
        keyStore.load(null);
        keyGenerator.init(new
                KeyGenParameterSpec.Builder(KEY_NAME,
                KeyProperties.PURPOSE_ENCRYPT |
                        KeyProperties.PURPOSE_DECRYPT)
                .setBlockModes(KeyProperties.BLOCK_MODE_CBC)
                .setUserAuthenticationRequired(true)
                .setEncryptionPaddings(
                        KeyProperties.ENCRYPTION_PADDING_PKCS7)
                .build());
        keyGenerator.generateKey();
    } catch (NoSuchAlgorithmException |
            InvalidAlgorithmParameterException
            | CertificateException | IOException e) {
        throw new RuntimeException(e);
    }
}

@TargetApi(Build.VERSION_CODES.M)
public boolean cipherInit() {
    try {
        cipher = Cipher.getInstance(
                KeyProperties.KEY_ALGORITHM_AES + "/"
                        + KeyProperties.BLOCK_MODE_CBC + "/"
                        + KeyProperties.ENCRYPTION_PADDING_PKCS7);
    } catch (NoSuchAlgorithmException |
            NoSuchPaddingException e) {
        throw new RuntimeException("Failed to get Cipher", e);
    }

    try {
        keyStore.load(null);
        SecretKey key = (SecretKey) keyStore.getKey(KEY_NAME,
                null);
        cipher.init(Cipher.ENCRYPT_MODE, key);
        return true;
    } catch (KeyPermanentlyInvalidatedException e) {
        return false;
    } catch (KeyStoreException | CertificateException
            | UnrecoverableKeyException | IOException
            | NoSuchAlgorithmException | InvalidKeyException e) {
        throw new RuntimeException("Failed to init Cipher", e);
    }
}
}

我自己找到了解决方案。事实证明,Bio-metric 设备在读取指纹时会提供加密数据。我认为出于安全原因,phone 中的普通指纹传感器不提供此加密数据。开发人员可以对指纹传感器做的最接近的事情是查明指纹是否与 android 设备中已注册的指纹相匹配。因此,我不得不使用第三方 sdk。