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本文次要钻研一下PBE算法

PBE

PBE即Password Based Encryption，基于口令的加密，它是一种组合算法，即个别是哈希+对称算法，比方PBEWithMD5AndDES，就是用MD5做哈希，用DES做加解密，而其密钥则是口令+salt基于哈希函数计算而来

java示例

    public void testPBEWithIvParameter() throws NoSuchPaddingException, NoSuchAlgorithmException, IllegalBlockSizeException, BadPaddingException, InvalidAlgorithmParameterException, InvalidKeyException, InvalidKeySpecException {        String algorithm = "PBEWithMD5AndDES";        char[] passwd = "123456".toCharArray();        PBEKeySpec pbeKeySpec = new PBEKeySpec(passwd);        SecretKeyFactory kf = SecretKeyFactory.getInstance(algorithm);        SecretKey key = kf.generateSecret(pbeKeySpec);        byte[] salt = new byte[8];        Random random = new Random();        random.nextBytes(salt);        Cipher cp = Cipher.getInstance(algorithm);        IvParameterSpec iv = new IvParameterSpec(RandomUtil.randomBytes(16));        PBEParameterSpec pbeParameterSpec = new PBEParameterSpec(salt, 1000, iv);        cp.init(Cipher.ENCRYPT_MODE, key, pbeParameterSpec);        byte[] data = "helloworld".getBytes(StandardCharsets.UTF_8);        byte[] encrypted = cp.doFinal(data);        System.out.println(Base64.encode(encrypted));        Cipher cpDecrypt = Cipher.getInstance(algorithm);        cpDecrypt.init(Cipher.DECRYPT_MODE, key, pbeParameterSpec);        byte[] decryptBytes = cpDecrypt.doFinal(encrypted);        System.out.println(new String(decryptBytes));    }
几个参数，一个是口令，即passwd，一个是salt，随机盐值，一个是ivParameter

golang示例

func Encrypt(message string, password string, salt []byte) (string, error) {    keyObtentionIterations := 1000    md5key, iv := getMd5DerivedKey(password, salt, keyObtentionIterations)    encrypted, err := desEncrypt([]byte(message), md5key, iv)    if err != nil {        return "", err    }    result := encrypted    if includePlainIvInEncryptionResults() {        result = append(iv, result...)    }    if includePlainSaltInEncryptionResults() {        result = append(salt, result...)    }        return base64.StdEncoding.EncodeToString(result), nil}

小结

  • PBE即Password Based Encryption，基于口令的加密，它是一种组合算法，即个别是哈希+对称算法，比方PBEWithMD5AndDES，就是用MD5做哈希，用DES做加解密，而其密钥则是口令+salt基于哈希函数计算而来
  • 当应用固定salt和不应用ivParameter的DES的时候，同一个值，每次加密生成的密文是一样的，而应用随机salt和随机iv的时候，每次生成的密文是不一样的，这个时候密文会蕴含随机的salt和iv信息，在解密的时候可能正确解出明文