java使用google身份验证器实现动态口令验证的示例

HOTP(K,C) = Truncate(HMAC-SHA-1(K,C)) 

package com.auth.google;  import java.security.InvalidKeyException; import java.security.NoSuchAlgorithmException; import java.security.SecureRandom; import javax.crypto.Mac; import javax.crypto.spec.SecretKeySpec; import org.apache.commons.codec.binary.Base32; import org.apache.commons.codec.binary.Base64;  /**  *  *  * google身份验证器，java服务端实现  *  * @author yangbo  *  * @version 创建时间：2017年8月14日 上午10:10:02  *  *  */ public class GoogleAuthenticator {   // 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 t  *  The time in msec (System.currentTimeMillis() for example)  * @return  */  public boolean check_code(String secret, long 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 (hash == 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;  } } 

package com.auth.google;  import org.junit.Test;  /**  *  *  * 身份认证测试  *  * @author yangbo  *  * @version 创建时间：2017年8月14日 上午11:09:23  *  *  */ public class AuthTest {  //当测试authTest时候，把genSecretTest生成的secret值赋值给它  private static String secret="R2Q3S52RNXBTFTOM";   //@Test  public void genSecretTest() {// 生成密钥   secret = GoogleAuthenticator.generateSecretKey();  // 把这个qrcode生成二维码，用google身份验证器扫描二维码就能添加成功  String qrcode = GoogleAuthenticator.getQRBarcode("2816661736@qq.com", secret);  System.out.println("qrcode:" + qrcode + ",key:" + secret);  }  /**  * 对app的随机生成的code,输入并验证  */  @Test  public void verifyTest() {  long code = 807337;  long t = System.currentTimeMillis();  GoogleAuthenticator ga = new GoogleAuthenticator();  ga.setWindowSize(5);  boolean r = ga.check_code(secret, code, t);  System.out.println("检查code是否正确？" + r);  } }