# FingerprintVerification

**Repository Path**: hm0603/FingerprintVerification

## Basic Information

- **Project Name**: FingerprintVerification
- **Description**: 指纹验证
- **Primary Language**: Android
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 1
- **Forks**: 0
- **Created**: 2018-09-14
- **Last Updated**: 2020-12-19

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# 指纹识别

## Android 6.0到8.1的使用方式

需要的权限
```
    <uses-permission android:name="android.permission.USE_FINGERPRINT"/>
```
## 核心代码
获取指纹管理对象
```
FingerprintManagerCompat fingerprintManagerCompat = FingerprintManagerCompat.from(this);
```
判断指纹是否可用
```
    /**
     * 是否可以使用 指纹识别
     *
     * @param managerCompat 指纹识别模块管理对象(向下兼容)
     * @return 是否可用
     */
    private boolean canUseFingerprint(FingerprintManagerCompat managerCompat) {
        // 手机是否有职位识别模块
        if (!managerCompat.isHardwareDetected())
            return false;
        //是否已经录入指纹
        return managerCompat.hasEnrolledFingerprints();
    }
```

开始指纹识别
```
 //指纹验证取消信号对象 (用于控制取消指纹验证)
CancellationSignal cancellationSignal = new CancellationSignal();

/**
 * @param crypto 与调用关联的对象，如果不需要则为null.
 * @param flags 系统预留属性,此时应该为 0
 * @param cancel 控制取消指纹信号的对象
 * @param callback 指纹验证结果的回调函数
 * @param handler 指纹验证结果的 Handle 对象,一般使用 callback即可,向了解关于 handler 的使用跟踪以下源码就一目了然 {@link FingerprintManager)}
 */
fingerprintManagerCompat.authenticate(null, 0, cancellationSignal, new FingerprintCallback(), null);
//fingerprintManagerCompat.authenticate(new CryptoObjectHelper().buildCryptoObject(), 0, cancellationSignal, new FingerprintCallback(), null);
               
```

取消指纹验证
```
 //指纹验证是否取消
    if (!cancellationSignal.isCanceled()) {
        //取消指纹验证
        cancellationSignal.cancel();
    }
```
指纹验证结果的回调
```
private class FingerprintCallback extends FingerprintManagerCompat.AuthenticationCallback {
        /**
         * 当多次验证失败,该方法被调用,并且在将来的一段时间内不能在使用指纹验证.或 用户手动取消验证等...
         *
         * @param errMsgId  错误状态ID 可能是 {@link FingerprintManager#FINGERPRINT_ERROR_HW_UNAVAILABLE}
         *                  ,or {@link FingerprintManager#FINGERPRINT_ERROR_UNABLE_TO_PROCESS}
         *                  ,or {@link FingerprintManager#FINGERPRINT_ERROR_TIMEOUT}  验证超时
         *                  ,or {@link FingerprintManager#FINGERPRINT_ERROR_NO_SPACE}
         *                  ,or {@link FingerprintManager#FINGERPRINT_ERROR_CANCELED} 取消验证 {@link CancellationSignal#cancel()} 被调用
         *                  ,or {@link FingerprintManager#FINGERPRINT_ERROR_LOCKOUT} 多次验证失败
         *                  ,or {@link FingerprintManager#FINGERPRINT_ERROR_VENDOR}
         *                  ,or {@link FingerprintManager#FINGERPRINT_ERROR_LOCKOUT_PERMANENT}
         *                  ,or {@link FingerprintManager#FINGERPRINT_ERROR_USER_CANCELED} 其中一个.
         * @param errString 错误提示信息
         */
        @Override
        public void onAuthenticationError(int errMsgId, CharSequence errString) {
            super.onAuthenticationError(errMsgId, errString);
        }

        /**
         * 在验证过程中,遇到可恢复的异常时该方法被调用.(传感器脏，请把它擦干净。...)
         *
         * @param helpMsgId
         * @param helpString 提示信息
         */
        @Override
        public void onAuthenticationHelp(int helpMsgId, CharSequence helpString) {
            super.onAuthenticationHelp(helpMsgId, helpString);
        }

        /**
         * 指纹验证成功
         *
         * @param result
         */
        @Override
        public void onAuthenticationSucceeded(FingerprintManagerCompat.AuthenticationResult result) {
            super.onAuthenticationSucceeded(result);
        }

        /**
         * 指纹验证失败
         */
        @Override
        public void onAuthenticationFailed() {
            super.onAuthenticationFailed();
        }
    }
```

### 通用指纹验证加密对象
```

public class CryptoObjectHelper {

    //TODO 这可以是您想要的关键名称。该应用程序应该是唯一的。(一般使用 应用包名)
    private static final String KEY_NAME = "com.example.linhuaming.fingerprint_authentication_key";

    // We always use this keystore on Android.
    private static final String KEYSTORE_NAME = "AndroidKeyStore";

    // Should be no need to change these values.
    private static final String KEY_ALGORITHM = KeyProperties.KEY_ALGORITHM_AES;
    private static final String BLOCK_MODE = KeyProperties.BLOCK_MODE_CBC;
    private static final String ENCRYPTION_PADDING = KeyProperties.ENCRYPTION_PADDING_PKCS7;
    private static final String TRANSFORMATION = KEY_ALGORITHM + "/" +
            BLOCK_MODE + "/" +
            ENCRYPTION_PADDING;
    private KeyStore _keystore;

    public CryptoObjectHelper() {
        try {
            _keystore = KeyStore.getInstance(KEYSTORE_NAME);
            _keystore.load(null);
        } catch (KeyStoreException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        } catch (CertificateException e) {
            e.printStackTrace();
        }
    }

    public FingerprintManagerCompat.CryptoObject buildCryptoObject() {
        try {
            Cipher cipher = createCipher(true);
            if (cipher != null) {
                return new FingerprintManagerCompat.CryptoObject(cipher);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }


    private Cipher createCipher(boolean retry) throws Exception {
        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M)
            return null;
        Key key = GetKey();
        Cipher cipher = Cipher.getInstance(TRANSFORMATION);
        try {
            cipher.init(Cipher.ENCRYPT_MODE | Cipher.DECRYPT_MODE, key);
        } catch (KeyPermanentlyInvalidatedException e) {
            _keystore.deleteEntry(KEY_NAME);
            if (retry) {
                createCipher(false);
            } else {
                throw new Exception("Could not create the cipher for fingerprint authentication.", e);
            }
        }
        return cipher;
    }

    @RequiresApi(api = Build.VERSION_CODES.M)
    private Key GetKey() throws Exception {
        Key secretKey;
        if (!_keystore.isKeyEntry(KEY_NAME)) {
            CreateKey();
        }

        secretKey = _keystore.getKey(KEY_NAME, null);
        return secretKey;
    }

    @RequiresApi(api = Build.VERSION_CODES.M)
    private void CreateKey() throws Exception {
        KeyGenerator keyGen = KeyGenerator.getInstance(KEY_ALGORITHM, KEYSTORE_NAME);
        KeyGenParameterSpec keyGenSpec =
                new KeyGenParameterSpec.Builder(KEY_NAME, KeyProperties.PURPOSE_ENCRYPT | KeyProperties.PURPOSE_DECRYPT)
                        .setBlockModes(BLOCK_MODE)
                        .setEncryptionPaddings(ENCRYPTION_PADDING)
                        .setUserAuthenticationRequired(true)
                        .build();
        keyGen.init(keyGenSpec);
        keyGen.generateKey();
    }
}
```

## Android 9.0 生物识别
> 在Android 9.0 中 指纹识别 Api 已经被废弃

后续完善...敬请期待...