使用google身份验证器实现动态密码验证java

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; } }