双因子验证机制简单实现

@RestController
@RequestMapping("/twoFactor")
public class TwoFactorController {
    
    protected Map userSecret = new ConcurrentHashMap<>();
    @GetMapping("/bind")
    public String bind(@RequestParam String username) {
        String secret = MultiFactorAuthenticatorUtil.generateSecretKey();
        userSecret.put(username,secret);
        return MultiFactorAuthenticatorUtil.getQRBarcode(username, secret);
    }

    

    @PostMapping("/check")
    public Object check(@RequestParam String username, @RequestParam String codeInput) {
        String secret = userSecret.get(username);
        return MultiFactorAuthenticatorUtil.checkCode(secret, Long.parseLong(codeInput), System.currentTimeMillis());
    }
}

@Slf4j
public class MultiFactorAuthenticatorUtil {
    // this is the issuer, you can change it to your company/project name.
    private static final String ISSUER = "Hello";
    // you can change it to any string.
    private static final String SEED = "thisisgoogleauthenticator";
    // taken from Google pam docs - we probably don't need to mess with these
    private static final String RANDOM_NUMBER_ALGORITHM = "SHA1PRNG";
    private static final int SECRET_SIZE = 10;
    // suggest: the smaller the value, the safer it is. (from 1 to 17)
    private static final int WINDOW_SIZE = 1;

    public static String generateSecretKey() {
        try {
            SecureRandom sr = SecureRandom.getInstance(RANDOM_NUMBER_ALGORITHM);
            sr.setSeed(base64.decodebase64(SEED));
            byte[] buffer = sr.generateSeed(SECRET_SIZE);
            base32 codec = new base32();
            byte[] bEncodedKey = codec.encode(buffer);
            return new String(bEncodedKey);
        } catch (NoSuchAlgorithmException e) {
            log.error("generate secret exception：{[]}", e);
        }
        return null;
    }

    public static String getQRBarcode(String user, String secret) {
        String format = "otpauth://totp/%s?secret=%s&issuer=%s";
        String imageContent = String.format(format, user, secret, ISSUER);
        log.info(imageContent);
        return QRCodeUtil.getbase64QRCode(imageContent);
    }

    public static boolean checkCode(String secret, long code, long time) {
        base32 codec = new base32();
        byte[] decodedKey = codec.decode(secret);
        // convert unix msec time into a 30 second "window"
        // this is per the TOTP spec (see the RFC for details)
        long t = (time / 1000L) / 30L;
        // Window is used to check codes generated in the near past.
        // You can use this value to tune how far you're willing to go.
        for (int i = -WINDOW_SIZE; i <= WINDOW_SIZE; ++i) {
            long hash;
            try {
                hash = verifyCode(decodedKey, t + i);
            } catch (Exception e) {
                // Yes, this is bad form - but
                // the exceptions thrown would be rare and a static configuration problem
                e.printStackTrace();
                throw new RuntimeException(e.getMessage());
                //return false;
            }
            if (hash == code) {
                return true;
            }
        }
        // The validation code is invalid.
        return false;
    }

    private static int verifyCode(byte[] key, long t) throws NoSuchAlgorithmException, InvalidKeyException {
        byte[] data = new byte[8];
        long value = t;
        for (int i = 8; i-- > 0; value >>>= 8) {
            data[i] = (byte) value;
        }
        SecretKeySpec signKey = new SecretKeySpec(key, "HmacSHA1");
        Mac mac = Mac.getInstance("HmacSHA1");
        mac.init(signKey);
        byte[] hash = mac.doFinal(data);
        int offset = hash[20 - 1] & 0xF;
        // We're using a long because Java hasn't got unsigned int.
        long truncatedHash = 0;
        for (int i = 0; i < 4; ++i) {
            truncatedHash <<= 8;
            // We are dealing with signed bytes:
            // we just keep the first byte.
            truncatedHash |= (hash[offset + i] & 0xFF);
        }
        truncatedHash &= 0x7FFFFFFF;
        truncatedHash %= 1000000;
        return (int) truncatedHash;
    }

    private MultiFactorAuthenticatorUtil() {
    }
}

public class QRCodeUtil {
    
    private static final Integer WIDTH = 140;
    
    private static final Integer HEIGHT = 140;

    
    private static final Integer LOGO_WIDTH = 22;
    
    private static final Integer LOGO_HEIGHT = 22;

    
    private static final String IMAGE_FORMAT = "png";
    private static final String CHARSET = "utf-8";
    
    private static final String base64_IMAGE = "data:image/png;base64,%s";

    
    public static String getbase64QRCode(String content) {
        return getbase64Image(content, WIDTH, HEIGHT, null, null, null);
    }

    
    public static String getbase64QRCode(String content, String logoUrl) {
        return getbase64Image(content, WIDTH, HEIGHT, logoUrl, LOGO_WIDTH, LOGO_HEIGHT);
    }

    
    public static String getbase64QRCode(String content, Integer width, Integer height, String logoUrl, Integer logoWidth, Integer logoHeight) {
        return getbase64Image(content, width, height, logoUrl, logoWidth, logoHeight);
    }

    private static String getbase64Image(String content, Integer width, Integer height, String logoUrl, Integer logoWidth, Integer logoHeight) {
        ByteArrayOutputStream os = new ByteArrayOutputStream();
        BufferedImage bufferedImage = crateQRCode(content, width, height, logoUrl, logoWidth, logoHeight);
        try {
            ImageIO.write(bufferedImage, IMAGE_FORMAT, os);
        } catch (IOException e) {
            System.out.println("[生成二维码，错误"+e+"]");
        }
        // 转出即可直接使用
        return String.format(base64_IMAGE, base64.encode(os.toByteArray()));
    }


    
    private static BufferedImage crateQRCode(String content, Integer width, Integer height, String logoUrl, Integer logoWidth, Integer logoHeight) {
        if (StrUtil.isNotBlank(content)) {
            ServletOutputStream stream = null;
            HashMap hints = new HashMap<>(4);
            // 指定字符编码为utf-8
            hints.put(EncodeHintType.CHARACTER_SET, CHARSET);
            // 指定二维码的纠错等级为中级
            hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.M);
            // 设置图片的边距
            hints.put(EncodeHintType.MARGIN, 2);
            try {
                QRCodeWriter writer = new QRCodeWriter();
                BitMatrix bitMatrix = writer.encode(content, BarcodeFormat.QR_CODE, width, height, hints);
                BufferedImage bufferedImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
                for (int x = 0; x < width; x++) {
                    for (int y = 0; y < height; y++) {
                        bufferedImage.setRGB(x, y, bitMatrix.get(x, y) ? 0xFF000000 : 0xFFFFFFFF);
                    }
                }
                if (StrUtil.isNotBlank(logoUrl)) {
                    insertLogo(bufferedImage, width, height, logoUrl, logoWidth, logoHeight);
                }
                return bufferedImage;
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                if (stream != null) {
                    try {
                        stream.flush();
                        stream.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }
        }
        return null;
    }

    
    private static void insertLogo(BufferedImage source, Integer width, Integer height, String logoUrl, Integer logoWidth, Integer logoHeight) throws Exception {
        // logo 源可为 File/InputStream/URL
        Image src = ImageIO.read(new URL(logoUrl));
        // 插入LOGO
        Graphics2D graph = source.createGraphics();
        int x = (width - logoWidth) / 2;
        int y = (height - logoHeight) / 2;
        graph.drawImage(src, x, y, logoWidth, logoHeight, null);
        Shape shape = new RoundRectangle2D.Float(x, y, logoWidth, logoHeight, 6, 6);
        graph.setStroke(new BasicStroke(3f));
        graph.draw(shape);
        graph.dispose();
    }


    
    public static void getQRCode(String content, OutputStream output) throws IOException {
        BufferedImage image = crateQRCode(content, WIDTH, HEIGHT, null, null, null);
        ImageIO.write(image, IMAGE_FORMAT, output);
    }

    
    public static void getQRCode(String content, String logoUrl, OutputStream output) throws Exception {
        BufferedImage image = crateQRCode(content, WIDTH, HEIGHT, logoUrl, LOGO_WIDTH, LOGO_HEIGHT);
        ImageIO.write(image, IMAGE_FORMAT, output);
    }

}

依赖

            com.google.zxing
            javase
            3.3.3