JAVA加密解密之DH(Diffie-Hellman)算法

x33g5p2x  于2021-12-25 转载在 其他  
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DH算法简介

Diffie-Hellman算法(D-H算法),密钥一致协议。是由公开密钥密码体制的奠基人Diffie和Hellman所提出的一种思想。简单的说就是允许两名用户在公开媒体上交换信息以生成”一致”的、可以共享的密钥。换句话说,就是由甲方产出一对密钥(公钥、私钥),乙方依照甲方公钥产生乙方密钥对(公钥、私钥)。以此为基线,作为数据传输保密基础,同时双方使用同一种对称加密算法构建本地密钥(SecretKey)对数据加密。这样,在互通了本地密钥(SecretKey)算法后,甲乙双方公开自己的公钥,使用对方的公钥和刚才产生的私钥加密数据,同时可以使用对方的公钥和自己的私钥对数据解密。不单单是甲乙双方两方,可以扩展为多方共享数据通讯,这样就完成了网络交互数据的安全通讯!该算法源于中国的同余定理——中国馀数定理。

  1. 甲方构建密钥对儿,将公钥公布给乙方,将私钥保留;双方约定数据加密算法;乙方通过甲方公钥构建密钥对儿,将公钥公布给甲方,将私钥保留。
  2. 甲方使用私钥、乙方公钥、约定数据加密算法构建本地密钥,然后通过本地密钥加密数据,发送给乙方加密后的数据;乙方使用私钥、甲方公钥、约定数据加密算法构建本地密钥,然后通过本地密钥对数据解密。
  3. 乙方使用私钥、甲方公钥、约定数据加密算法构建本地密钥,然后通过本地密钥加密数据,发送给甲方加密后的数据;甲方使用私钥、乙方公钥、约定数据加密算法构建本地密钥,然后通过本地密钥对数据解密。

DH算法实现

package com.jianggujin.codec;

import java.io.InputStream;
import java.io.OutputStream;
import java.security.Key;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.PublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

import javax.crypto.Cipher;
import javax.crypto.KeyAgreement;
import javax.crypto.SecretKey;
import javax.crypto.interfaces.DHPublicKey;
import javax.crypto.spec.DHParameterSpec;

import com.jianggujin.codec.util.JCipherInputStream;
import com.jianggujin.codec.util.JCipherOutputStream;
import com.jianggujin.codec.util.JCodecException;

/** * Diffie-Hellman算法(D-H算法),密钥一致协议。是由公开密钥密码体制的奠基人Diffie和Hellman所提出的一种思想。 * 简单的说就是允许两名用户在公开媒体上交换信息以生成"一致"的、可以共享的密钥。换句话说,就是由甲方产出一对密钥(公钥、私钥), * 乙方依照甲方公钥产生乙方密钥对(公钥、私钥)。以此为基线,作为数据传输保密基础,同时双方使用同一种对称加密算法构建本地密钥(SecretKey)对数据加密 * 。这样,在互通了本地密钥(SecretKey)算法后,甲乙双方公开自己的公钥,使用对方的公钥和刚才产生的私钥加密数据, * 同时可以使用对方的公钥和自己的私钥对数据解密。不单单是甲乙双方两方,可以扩展为多方共享数据通讯,这样就完成了网络交互数据的安全通讯! * 该算法源于中国的同余定理——中国馀数定理 * <ol> * <li>甲方构建密钥对儿,将公钥公布给乙方,将私钥保留;双方约定数据加密算法;乙方通过甲方公钥构建密钥对儿,将公钥公布给甲方,将私钥保留。</li> * <li>甲方使用私钥、乙方公钥、约定数据加密算法构建本地密钥,然后通过本地密钥加密数据,发送给乙方加密后的数据;乙方使用私钥、甲方公钥、 * 约定数据加密算法构建本地密钥,然后通过本地密钥对数据解密。</li> * <li>乙方使用私钥、甲方公钥、约定数据加密算法构建本地密钥,然后通过本地密钥加密数据,发送给甲方加密后的数据;甲方使用私钥、乙方公钥、 * 约定数据加密算法构建本地密钥,然后通过本地密钥对数据解密。</li> * </ol> * * @author jianggujin * */
public class JDH {

   private final static String ALGORITHM = "DH";

   /** * 对称算法 * * @author jianggujin * */
   public static enum JDHSymmetricalAlgorithm {
      DES, DESede;
      public String getName() {
         return this.name();
      }
   }

   /** * 初始化甲方密钥 * * @return */
   public static KeyPair initPartyAKey() {
      return initPartyAKey(1024);
   }

   /** * 初始化甲方密钥 * * @param keySize * @return */
   public static KeyPair initPartyAKey(int keySize) {
      try {
         KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance(ALGORITHM);
         keyPairGen.initialize(keySize);
         return keyPairGen.generateKeyPair();
      } catch (NoSuchAlgorithmException e) {
         throw new JCodecException(e);
      }
   }

   /** * 初始化乙方密钥 * * @param partyAPublicKey * 甲方公钥 * @return */
   public static KeyPair initPartyBKey(byte[] partyAPublicKey) {
      try {
         X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(partyAPublicKey);
         KeyFactory keyFactory = KeyFactory.getInstance(ALGORITHM);
         PublicKey pubKey = keyFactory.generatePublic(x509KeySpec);

         // 由甲方公钥构建乙方密钥
         DHParameterSpec dhParamSpec = ((DHPublicKey) pubKey).getParams();

         KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance(keyFactory.getAlgorithm());
         keyPairGenerator.initialize(dhParamSpec);

         return keyPairGenerator.generateKeyPair();
      } catch (Exception e) {
         throw new JCodecException(e);
      }
   }

   /** * 加密 * * @param data * 加密数据 * @param privateKey * 己方私钥 * @param publicKey * 对方公钥 * @param algorithm * 对称算法 * @return */
   public static byte[] encrypt(byte[] data, byte[] privateKey, byte[] publicKey, String algorithm) {
      // 数据加密
      Cipher cipher = getEncryptCipher(privateKey, publicKey, algorithm);

      try {
         return cipher.doFinal(data);
      } catch (Exception e) {
         throw new JCodecException(e);
      }
   }

   /** * 包裹输出流,包裹后的输出流为加密输出流 * * @param out * @param privateKey * @param publicKey * @param algorithm * @return */
   public static OutputStream wrap(OutputStream out, byte[] privateKey, byte[] publicKey, String algorithm) {
      // 数据加密
      Cipher cipher = getEncryptCipher(privateKey, publicKey, algorithm);

      return new JCipherOutputStream(cipher, out);
   }

   /** * 获得加密模式的{@link Cipher} * * @param privateKey * @param publicKey * @param algorithm * @return */
   public static Cipher getEncryptCipher(byte[] privateKey, byte[] publicKey, String algorithm) {
      return getCipher(privateKey, publicKey, algorithm, Cipher.ENCRYPT_MODE);
   }

   /** * 解密 * * @param data * 解密数据 * @param privateKey * 己方私钥 * @param publicKey * 对方公钥 * @param algorithm * 对称算法 * @return */
   public static byte[] decrypt(byte[] data, byte[] privateKey, byte[] publicKey, String algorithm) {
      // 数据解密
      Cipher cipher = getDecryptCipher(privateKey, publicKey, algorithm);
      try {
         return cipher.doFinal(data);
      } catch (Exception e) {
         throw new JCodecException(e);
      }
   }

   /** * 包裹输入流,原输入流为加密数据输入流 * * @param in * @param privateKey * @param publicKey * @param algorithm * @return */
   public static InputStream wrap(InputStream in, byte[] privateKey, byte[] publicKey, String algorithm) {
      // 数据解密
      Cipher cipher = getDecryptCipher(privateKey, publicKey, algorithm);
      return new JCipherInputStream(cipher, in);
   }

   /** * 获得解密模式的{@link Cipher} * * @param privateKey * @param publicKey * @param algorithm * @return */
   public static Cipher getDecryptCipher(byte[] privateKey, byte[] publicKey, String algorithm) {
      return getCipher(privateKey, publicKey, algorithm, Cipher.DECRYPT_MODE);
   }

   private static Cipher getCipher(byte[] privateKey, byte[] publicKey, String algorithm, int opmode) {
      // 生成本地密钥
      SecretKey secretKey = getSecretKey(privateKey, publicKey, algorithm);

      try {
         // 数据加密
         Cipher cipher = Cipher.getInstance(secretKey.getAlgorithm());
         cipher.init(opmode, secretKey);
         return cipher;
      } catch (Exception e) {
         throw new JCodecException(e);
      }
   }

   /** * 获得密钥 * * @param privateKey * 己方私钥 * @param publicKey * 对方公钥 * @param algorithm * 对称算法 * @return */
   private static SecretKey getSecretKey(byte[] privateKey, byte[] publicKey, String algorithm) {
      try {
         KeyFactory keyFactory = KeyFactory.getInstance(ALGORITHM);
         X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(publicKey);
         PublicKey pubKey = keyFactory.generatePublic(x509KeySpec);

         PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(privateKey);
         Key priKey = keyFactory.generatePrivate(pkcs8KeySpec);

         KeyAgreement keyAgree = KeyAgreement.getInstance(keyFactory.getAlgorithm());
         keyAgree.init(priKey);
         keyAgree.doPhase(pubKey, true);

         // 生成本地密钥
         return keyAgree.generateSecret(algorithm);
      } catch (Exception e) {
         throw new JCodecException(e);
      }
   }
}

测试代码:

package com.jianggujin.codec.test;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.security.KeyPair;

import org.junit.Test;

import com.jianggujin.codec.JBase64;
import com.jianggujin.codec.JBase64.JEncoder;
import com.jianggujin.codec.JDH;
import com.jianggujin.codec.JDH.JDHSymmetricalAlgorithm;

public class DHTest {
   String str = "jianggujin";
   File file = new File(getClass().getSimpleName() + ".dat");

   @Test
   public void test() throws Exception {
      System.out.println("原串:" + str);
      JEncoder encoder = JBase64.getEncoder();
      KeyPair keyPairA = JDH.initPartyAKey();
      byte[] keyPairAPrivate = keyPairA.getPrivate().getEncoded();
      byte[] keyPairAPublic = keyPairA.getPublic().getEncoded();
      System.out.println("甲方私钥:" + encoder.encodeToString(keyPairAPrivate, "UTF-8"));
      System.out.println("甲方公钥:" + encoder.encodeToString(keyPairAPublic, "UTF-8"));
      KeyPair keyPairB = JDH.initPartyBKey(keyPairAPublic);
      byte[] keyPairBPrivate = keyPairB.getPrivate().getEncoded();
      byte[] keyPairBPublic = keyPairB.getPublic().getEncoded();
      System.out.println("乙方私钥:" + encoder.encodeToString(keyPairBPrivate, "UTF-8"));
      System.out.println("乙方公钥:" + encoder.encodeToString(keyPairBPublic, "UTF-8"));
      for (JDHSymmetricalAlgorithm algorithm : JDHSymmetricalAlgorithm.values()) {
         System.out.println("-----------------------------------------");
         System.out.println("对称算法:" + algorithm.getName());
         byte[] encrypt = JDH.encrypt(str.getBytes(), keyPairAPrivate, keyPairBPublic, algorithm.getName());
         System.out.println("加密:" + encoder.encodeToString(encrypt, "UTF-8"));
         System.out
               .println("解密:" + new String(JDH.decrypt(encrypt, keyPairBPrivate, keyPairAPublic, algorithm.getName())));

         System.out.print("输出流加密:" + file.getAbsolutePath());
         OutputStream out = JDH.wrap(new FileOutputStream(file), keyPairAPrivate, keyPairBPublic, algorithm.getName());
         out.write(str.getBytes());
         out.flush();
         out.close();
         System.out.println();
         System.out.print("输入流解密:");
         InputStream in = JDH.wrap(new FileInputStream(file), keyPairBPrivate, keyPairAPublic, algorithm.getName());
         byte[] buffer = new byte[1024];
         int len = in.read(buffer);
         System.out.println(new String(buffer, 0, len));
      }
   }
}

测试结果:
原串:jianggujin
甲方私钥:MIIBZwIBADCCARsGCSqGSIb3DQEDATCCAQwCgYEA/X9TgR11EilS30qcLuzk5/YRt1I870QAwx4/gLZRJmlFXUAiUftZPY1Y+r/F9bow9subVWzXgTuAHTRv8mZgt2uZUKWkn5/oBHsQIsJPu6nX/rfGG/g7V+fGqKYVDwT7g/bTxR7DAjVUE1oWkTL2dfOuK2HXKu/yIgMZndFIAccCgYEA9+GghdabPd7LvKtcNrhXuXmUr7v6OuqC+VdMCz0HgmdRWVeOutRZT+ZxBxCBgLRJFnEj6EwoFhO3zwkyjMim4TwWeotUfI0o4KOuHiuzpnWRbqN/C/ohNWLx+2J6ASQ7zKTxvqhRkImog9/hWuWfBpKLZl6Ae1UlZAFMO/7PSSoCAgIABEMCQQCKZ/IM4bTS0YkWGsMGFY6NAAICuvHpvhSBaPZ3Le4PS/owyrEnsiS3AXig5OYYko/fVvIBz1kOaKTl/0tsQLtt
甲方公钥: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
乙方私钥:MIIBZwIBADCCARsGCSqGSIb3DQEDATCCAQwCgYEA/X9TgR11EilS30qcLuzk5/YRt1I870QAwx4/gLZRJmlFXUAiUftZPY1Y+r/F9bow9subVWzXgTuAHTRv8mZgt2uZUKWkn5/oBHsQIsJPu6nX/rfGG/g7V+fGqKYVDwT7g/bTxR7DAjVUE1oWkTL2dfOuK2HXKu/yIgMZndFIAccCgYEA9+GghdabPd7LvKtcNrhXuXmUr7v6OuqC+VdMCz0HgmdRWVeOutRZT+ZxBxCBgLRJFnEj6EwoFhO3zwkyjMim4TwWeotUfI0o4KOuHiuzpnWRbqN/C/ohNWLx+2J6ASQ7zKTxvqhRkImog9/hWuWfBpKLZl6Ae1UlZAFMO/7PSSoCAgIABEMCQQDfg2OOQ+Rz4eRaatC0AKhNtA5i7KIrss7uM7Vtv2ls7zRCKWwXP5nRdbZAlO96tS1vF9AIZsYI82e8fQSBVfbX
乙方公钥: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
—————————————–
对称算法:DES
加密:zBJhlhWDFme0qIlClaBUQw==
解密:jianggujin
输出流加密:F:\workspace\java\eclipse\JCodec\DHTest.dat
输入流解密:jianggujin
—————————————–
对称算法:DESede
加密:0TFsnTdcA3JuJH2ZYn1ZcQ==
解密:jianggujin
输出流加密:F:\workspace\java\eclipse\JCodec\DHTest.dat
输入流解密:jianggujin

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