content: /*
   * Copyright ©2015-2023 Jaemon. All Rights Reserved.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   * http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package com.github.jaemon.dinger.utils;
  
  import javax.crypto.Cipher;
  import java.security.*;
  import java.security.interfaces.RSAPrivateKey;
  import java.security.interfaces.RSAPublicKey;
  import java.security.spec.PKCS8EncodedKeySpec;
  import java.security.spec.RSAPrivateKeySpec;
  import java.security.spec.RSAPublicKeySpec;
  import java.security.spec.X509EncodedKeySpec;
  
  import static com.github.jaemon.dinger.utils.DingerUtils.base64ToByteArray;
  import static com.github.jaemon.dinger.utils.DingerUtils.byteArrayToBase64;
  
  
  /**
   * Config Tools
   *
   * @author Jaemon
   * @since 1.0
   */
  public class ConfigTools {
  
      private ConfigTools() {}
  
      private static final String DEFAULT_PRIVATE_KEY_STRING = "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";
      public static final String DEFAULT_PUBLIC_KEY_STRING = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCt1JDrj987AB2qeCJj17oVbJIihptz13DP16NNgm65gWBzG9GxrgcnrEqV4Xqejj1hnayFui7w50uor8la7A3gXfNkEuipnxDEVSaKnqlWct5qYbLQDrRyuDhrQARaIF8NkXw0bpxquRlvbIReA1hYa1lrASv1BrO5Ca1Yq+r++wIDAQAB";
  
      public static void main(String[] args) throws Exception {
          if (args.length == 0) {
              System.out.println("secret is empty");
              return;
          }
  
          String password = args[0];
          String[] arr = genKeyPair(1024);
          System.out.println("privateKey: " + arr[0]);
          System.out.println("decryptKey: " + arr[1]);
          String encrypt = encrypt(arr[0], password);
          System.out.println("encrypt tokenId: " + encrypt);
          String decrypt = decrypt(arr[1], encrypt);
          System.out.println("decrypt tokenId:" + decrypt);
      }
  
      public static String decrypt(String cipherText) throws Exception {
          return decrypt((String) null, cipherText);
      }
  
      public static String decrypt(String publicKeyText, String cipherText)
              throws Exception {
          PublicKey publicKey = getPublicKey(publicKeyText);
  
          return decrypt(publicKey, cipherText);
      }
  
      public static PublicKey getPublicKey(String publicKeyText) {
          if (publicKeyText == null || publicKeyText.length() == 0) {
              publicKeyText = DEFAULT_PUBLIC_KEY_STRING;
          }
  
          try {
              byte[] publicKeyBytes = base64ToByteArray(publicKeyText);
              X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(
                      publicKeyBytes);
  
              KeyFactory keyFactory = KeyFactory.getInstance("RSA", "SunRsaSign");
              return keyFactory.generatePublic(x509KeySpec);
          } catch (Exception e) {
              throw new IllegalArgumentException("Failed to get public key", e);
          }
      }
  
  
      public static String decrypt(PublicKey publicKey, String cipherText)
              throws Exception {
          Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
          try {
              cipher.init(Cipher.DECRYPT_MODE, publicKey);
          } catch (InvalidKeyException e) {
              // 因为 IBM JDK 不支持私钥加密, 公钥解密, 所以要反转公私钥
              // 也就是说对于解密, 可以通过公钥的参数伪造一个私钥对象欺骗 IBM JDK
              RSAPublicKey rsaPublicKey = (RSAPublicKey) publicKey;
              RSAPrivateKeySpec spec = new RSAPrivateKeySpec(rsaPublicKey.getModulus(), rsaPublicKey.getPublicExponent());
              Key fakePrivateKey = KeyFactory.getInstance("RSA").generatePrivate(spec);
              cipher = Cipher.getInstance("RSA");
              cipher.init(Cipher.DECRYPT_MODE, fakePrivateKey);
          }
  
          if (cipherText == null || cipherText.length() == 0) {
              return cipherText;
          }
  
          byte[] cipherBytes = base64ToByteArray(cipherText);
          byte[] plainBytes = cipher.doFinal(cipherBytes);
  
          return new String(plainBytes);
      }
  
      public static String encrypt(String plainText) throws Exception {
          return encrypt((String) null, plainText);
      }
  
      public static String encrypt(String key, String plainText) throws Exception {
          if (key == null) {
              key = DEFAULT_PRIVATE_KEY_STRING;
          }
  
          byte[] keyBytes = base64ToByteArray(key);
          return encrypt(keyBytes, plainText);
      }
  
      public static String encrypt(byte[] keyBytes, String plainText)
              throws Exception {
          PKCS8EncodedKeySpec spec = new PKCS8EncodedKeySpec(keyBytes);
          KeyFactory factory = KeyFactory.getInstance("RSA", "SunRsaSign");
          PrivateKey privateKey = factory.generatePrivate(spec);
          Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
          try {
              cipher.init(Cipher.ENCRYPT_MODE, privateKey);
          } catch (InvalidKeyException e) {
              //For IBM JDK, 原因请看解密方法中的说明
              RSAPrivateKey rsaPrivateKey = (RSAPrivateKey) privateKey;
              RSAPublicKeySpec publicKeySpec = new RSAPublicKeySpec(rsaPrivateKey.getModulus(), rsaPrivateKey.getPrivateExponent());
              Key fakePublicKey = KeyFactory.getInstance("RSA").generatePublic(publicKeySpec);
              cipher = Cipher.getInstance("RSA");
              cipher.init(Cipher.ENCRYPT_MODE, fakePublicKey);
          }
  
          byte[] encryptedBytes = cipher.doFinal(plainText.getBytes("UTF-8"));
          String encryptedString = byteArrayToBase64(encryptedBytes);
  
          return encryptedString;
      }
  
      public static byte[][] genKeyPairBytes(int keySize)
              throws NoSuchAlgorithmException, NoSuchProviderException {
          byte[][] keyPairBytes = new byte[2][];
  
          KeyPairGenerator gen = KeyPairGenerator.getInstance("RSA", "SunRsaSign");
          gen.initialize(keySize, new SecureRandom());
          KeyPair pair = gen.generateKeyPair();
  
          keyPairBytes[0] = pair.getPrivate().getEncoded();
          keyPairBytes[1] = pair.getPublic().getEncoded();
  
          return keyPairBytes;
      }
  
      public static String[] genKeyPair(int keySize)
              throws NoSuchAlgorithmException, NoSuchProviderException {
          byte[][] keyPairBytes = genKeyPairBytes(keySize);
          String[] keyPairs = new String[2];
  
          keyPairs[0] = byteArrayToBase64(keyPairBytes[0]);
          keyPairs[1] = byteArrayToBase64(keyPairBytes[1]);
  
          return keyPairs;
      }
  
  }