Google动态验证码作用：可以动态的生成一个6位数的验证码，可以用于双重验证，增加网站的安全性。
条件：首先需要在手机上下载一个Google 验证器。（google authenticator app）
还需要在你的项目中引入一个Jar最主要的
<dependency>
<groupId>commons-codec</groupId>
<artifactId>commons-codec</artifactId>
<version>1.13</version>
</dependency>
一个主要的方法
import org.apache.commons.codec.binary.Base32;
import org.apache.commons.codec.binary.Base64;
import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
public class GoogleAuthenticatorUtil {
// 生成的key长度( Generate secret key length)
public static final int SECRET_SIZE = 10;
public static final String SEED = "g8GjEvTbW5oVSV7avL47357438reyhreyuryetredLDVKs2m0QN7vxRs2im5MDaNCWGmcD2rvcZx";
// Java实现随机数算法
public static final String RANDOM_NUMBER_ALGORITHM = "SHA1PRNG";
// 最多可偏移的时间
int window_size = 3; // default 3 - max 17
/**
* set the windows size. This is an integer value representing the number of
* 30 second windows we allow The bigger the window, the more tolerant of
* clock skew we are.
*
* @param s
* window size - must be >=1 and <=17. Other values are ignored
*/
public void setWindowSize(int s) {
if (s >= 1 && s <= 17)
window_size = s;
}
/**
* Generate a random secret key. This must be saved by the server and
* associated with the users account to verify the code displayed by Google
* Authenticator. The user must register this secret on their device.
* 生成一个随机秘钥
*
* @return secret key
*/
public static String generateSecretKey() {
SecureRandom sr = null;
try {
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);
String encodedKey = new String(bEncodedKey);
return encodedKey;
} catch (NoSuchAlgorithmException e) {
// should never occur... configuration error
}
return null;
}
/**
* Return a URL that generates and displays a QR barcode. The user scans
* this bar code with the Google Authenticator application on their
* smartphone to register the auth code. They can also manually enter the
* secret if desired
*
* @param user
* user id (e.g. fflinstone)
* @param host
* host or system that the code is for (e.g. myapp.com)
* @param secret
* the secret that was previously generated for this user
* @return the URL for the QR code to scan
*/
public static String getQRBarcodeURL(String user, String host, String secret) {
String format = "http://www.google.com/chart?chs=200x200&chld=M%%7C0&cht=qr&chl=otpauth://totp/%s@%s?secret=%s";
return String.format(format, user, host, secret);
}
/**
* 生成一个google身份验证器，识别的字符串，只需要把该方法返回值生成二维码扫描就可以了。
*
* @param user
* 账号
* @param secret
* 密钥
* @return
*/
public static String getQRBarcode(String user, String secret) {
String format = "otpauth://totp/%s?secret=%s";
return String.format(format, user, secret);
}
/**
* Check the code entered by the user to see if it is valid 验证code是否合法
*
* @param secret
* The users secret.
* @param code
* The code displayed on the users device
* @param timeMsec
* The time in msec (System.currentTimeMillis() for example)
* @return
*/
public boolean check_code(String secret, String code, long timeMsec) {
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 = (timeMsec / 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 = verify_code(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 (String.format ( "%06d",hash ).equals(code)) {
return true;
}
}
// The validation code is invalid.
return false;
}
private static int verify_code(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;
}
}
做一下测试
private static String secret = "MRHMHLZPFBZEZWQ3";
@Test
public void getSecret(){//首先跑这个类，成功后得到的secret要赋给上面的secret
secret = GoogleAuthenticatorUtil.generateSecretKey();
// String qrCode = GoogleAuthenticatorUtil.getQRBarcodeURL("haha","http://10.10.10.124:8092",secret);
String qrCode = GoogleAuthenticatorUtil.getQRBarcode("haha",secret);
System.out.println("secret "+secret + " qrCode " + qrCode );//qrcode这个我们可以最为二维码的值，我这个是在前端用qrcode.min.js生成的一个二维码（需要用户扫码用的），将值加进去就可以了。
}
@Test
public void testValidCode(){
String code = "105799";//这个值是你再Google APP中拿到的动态验证码
long time = System.currentTimeMillis ();
GoogleAuthenticatorUtil g = new GoogleAuthenticatorUtil();
System.out.println("secret "+secret );
boolean result = g.check_code (secret,code,time);
System.out.println ( result );//true就是表示验证码成功，否则失败
}
同时生成的二维码，我们除了用前端的qrcode.min.js我们还可以用java生成一个二维码图片显示在页面上
需要一些google的jar包
import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.client.j2se.MatrixToImageWriter;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.qrcode.QRCodeWriter;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
import javax.imageio.ImageIO;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.HashMap;
/**宽，height:高。content就是我们也要设置的二维码的值，google验证器的格式是
"otpauth://totp/" + user+ "?secret=" + secret;
public class QRCodeUtil {
public static void createQRCode(HttpServletResponse response, String content, int width, int height) throws IOException {
if (!StringUtil.isNullOrEmpty(content)) {
response.setDateHeader("Expires", 0);
// Set standard HTTP/1.1 no-cache headers.
response.setHeader("Cache-Control", "no-store, no-cache, must-revalidate");
// Set IE extended HTTP/1.1 no-cache headers (use addHeader).
response.addHeader("Cache-Control", "post-check=0, pre-check=0");
// Set standard HTTP/1.0 no-cache header.
response.setHeader("Pragma", "no-cache");
// return a jpeg
response.setContentType("image/png");
ServletOutputStream out = response.getOutputStream();
try {
HashMap<EncodeHintType, Comparable> hints = new HashMap<>(3);
hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.M);
hints.put(EncodeHintType.MARGIN, 2);
QRCodeWriter writer = new QRCodeWriter();
BitMatrix bitMatrix = writer.encode(content, BarcodeFormat.QR_CODE, width, height, hints);
BufferedImage bufferedImage = MatrixToImageWriter.toBufferedImage(bitMatrix);
ImageIO.write(bufferedImage, "png", out);
} catch (Exception e) {
e.printStackTrace();
} finally {
if (out != null) {
out.flush();
out.close();
}
}
}
}
}
我们除了自己写类，也可以引入google验证器的jar
<dependency>
<groupId>com.warrenstrange</groupId>
<artifactId>googleauth</artifactId>
<version>1.2.0</version>
</dependency>
GoogleAuthenticator gAuth = new GoogleAuthenticator();
String secret= gAuth.createCredentials().getKey();//得到secret
gAuth.authorize(key, code)//验证