Java笔记-DH密钥交换获取密钥及AES加解密

灰太狼 2022-09-10 09:27 263阅读 0赞

DH密钥交换是这样的：

![watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBASVQxOTk1_size_20_color_FFFFFF_t_70_g_se_x_16][]

程序运行截图如下：

D:\java8\content\bin\java.exe -javaagent:D:\idea\content\lib\idea_rt.jar=61009:D:\idea\content\bin -Dfile.encoding=UTF-8 -classpath D:\java8\content\jre\lib\charsets.jar;D:\java8\content\jre\lib\deploy.jar;D:\java8\content\jre\lib\ext\access-bridge-64.jar;D:\java8\content\jre\lib\ext\cldrdata.jar;D:\java8\content\jre\lib\ext\dnsns.jar;D:\java8\content\jre\lib\ext\jaccess.jar;D:\java8\content\jre\lib\ext\jfxrt.jar;D:\java8\content\jre\lib\ext\localedata.jar;D:\java8\content\jre\lib\ext\nashorn.jar;D:\java8\content\jre\lib\ext\sunec.jar;D:\java8\content\jre\lib\ext\sunjce_provider.jar;D:\java8\content\jre\lib\ext\sunmscapi.jar;D:\java8\content\jre\lib\ext\sunpkcs11.jar;D:\java8\content\jre\lib\ext\zipfs.jar;D:\java8\content\jre\lib\javaws.jar;D:\java8\content\jre\lib\jce.jar;D:\java8\content\jre\lib\jfr.jar;D:\java8\content\jre\lib\jfxswt.jar;D:\java8\content\jre\lib\jsse.jar;D:\java8\content\jre\lib\management-agent.jar;D:\java8\content\jre\lib\plugin.jar;D:\java8\content\jre\lib\resources.jar;D:\java8\content\jre\lib\rt.jar;D:\IDEAProject\DHDemo\target\classes;D:\newGenRepository\repository\commons-codec\commons-codec\1.11\commons-codec-1.11.jar cn.it1995.Test
    服务端公钥:MIHgMIGXBgkqhkiG9w0BAwEwgYkCQQD8poLOjhLKuibvzPcRDlJtsHiwXt7LzR60ogjzrhYXrgHzW5Gkfm32NBPF4S7QiZvNEyrNUNmRUb3EPuc3WS4XAkBnhHGyepz0TukaScUUfbGpqvJE8FpDTWSGkx0tFCcbnjUDC3H9c9oXkGmzLik1Yw4cIGI1TQ2iCmxBblC+eUykAgIBgANEAAJBAKvnBpIb+eOiVyKDGkTsSc+8lOlgMdu6hEumGfdl6+yOyu3+Rlw9PwbiJ1Fd7qDD/vpI5+nktCA3C5FstsCF/ZM=
    服务端私钥:MIHSAgEAMIGXBgkqhkiG9w0BAwEwgYkCQQD8poLOjhLKuibvzPcRDlJtsHiwXt7LzR60ogjzrhYXrgHzW5Gkfm32NBPF4S7QiZvNEyrNUNmRUb3EPuc3WS4XAkBnhHGyepz0TukaScUUfbGpqvJE8FpDTWSGkx0tFCcbnjUDC3H9c9oXkGmzLik1Yw4cIGI1TQ2iCmxBblC+eUykAgIBgAQzAjEA1JWmuoylaemaZlWJTPz887uUitPZdphkrhv79XsIlHBLjmFB6dFQLJ/6TLaQGNLz
    客户端公钥:MIHgMIGXBgkqhkiG9w0BAwEwgYkCQQD8poLOjhLKuibvzPcRDlJtsHiwXt7LzR60ogjzrhYXrgHzW5Gkfm32NBPF4S7QiZvNEyrNUNmRUb3EPuc3WS4XAkBnhHGyepz0TukaScUUfbGpqvJE8FpDTWSGkx0tFCcbnjUDC3H9c9oXkGmzLik1Yw4cIGI1TQ2iCmxBblC+eUykAgIBgANEAAJBAOhfxWPk/NI4wAWhaM14wJVgdUObef9J2kAzRy5yyi5QfrSabMpQh64oE72KzKMjMhgvPfqYSw5NYFu8V8EMW20=
    客户端私钥:MIHSAgEAMIGXBgkqhkiG9w0BAwEwgYkCQQD8poLOjhLKuibvzPcRDlJtsHiwXt7LzR60ogjzrhYXrgHzW5Gkfm32NBPF4S7QiZvNEyrNUNmRUb3EPuc3WS4XAkBnhHGyepz0TukaScUUfbGpqvJE8FpDTWSGkx0tFCcbnjUDC3H9c9oXkGmzLik1Yw4cIGI1TQ2iCmxBblC+eUykAgIBgAQzAjEAtjb/+dXXhPMI3xubgp3LipUgNYjMtWok30cn3KxGgkspHEqI35h+TLRmT2CZDopA
    客户端计算出的AES密钥:g/tQbIkTCH3I1gXCVNObyyHKsBkWXTsNJIiPG3gVJII=
    服务端计算出的AES密钥:g/tQbIkTCH3I1gXCVNObyyHKsBkWXTsNJIiPG3gVJII=
    原文:Hello world, 中文
    密文:���-�5�5�u�ɫ5>#�Ij>�/hC�
    解密:Hello world, 中文
    
    Process finished with exit code 0

程序结构如下：

![watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBASVQxOTk1_size_12_color_FFFFFF_t_70_g_se_x_16][]

代码如下：

DataSecret.java

package cn.it1995;
    
    import javax.crypto.Cipher;
    import javax.crypto.SecretKey;
    import javax.crypto.spec.SecretKeySpec;
    
    public class DataSecret {
    
        private static final String SELECT_ALGORITHM = "AES";   //DES、DESede或者AES
    
        public static byte[] encrypt(byte[] data, byte[] key) throws Exception {
    
            //生成本地密钥
            SecretKey secretKey = new SecretKeySpec(key, SELECT_ALGORITHM);
    
            //加密
            Cipher cipher = Cipher.getInstance(secretKey.getAlgorithm());
            cipher.init(Cipher.ENCRYPT_MODE, secretKey);
            return cipher.doFinal(data);
        }
    
        public static byte[] decrypt(byte[] data, byte[] key) throws Exception {
    
            SecretKey secretKey = new SecretKeySpec(key, SELECT_ALGORITHM);
            Cipher cipher = Cipher.getInstance(secretKey.getAlgorithm());
            cipher.init(Cipher.DECRYPT_MODE, secretKey);
            return cipher.doFinal(data);
        }
    }

DH.java

package cn.it1995;
    
    import javax.crypto.KeyAgreement;
    import javax.crypto.SecretKey;
    import javax.crypto.interfaces.DHPrivateKey;
    import javax.crypto.interfaces.DHPublicKey;
    import java.security.*;
    import java.security.spec.PKCS8EncodedKeySpec;
    import java.security.spec.X509EncodedKeySpec;
    import java.util.HashMap;
    import java.util.Map;
    
    public abstract class DH {
    
        private static final String KEY_ALGORITHM = "DH";
        private static final int KEY_SIZE = 512;
        private static final String PUBLIC_KEY = "DHPublicKey";
        private static final String PRIVATE_KEY = "DHPrivateKey";
        private static final String SELECT_ALGORITHM = "AES";   //DES、DESede或者AES
    
        /***
         * 初始化服务端密钥
         * @return
         * @throws Exception
         */
        public static Map<String, Object> initKey() throws Exception {
    
            KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance(KEY_ALGORITHM);
            keyPairGenerator.initialize(KEY_SIZE);
            KeyPair keyPair = keyPairGenerator.generateKeyPair();
            DHPublicKey publicKey = (DHPublicKey)keyPair.getPublic();
            DHPrivateKey privateKey = (DHPrivateKey)keyPair.getPrivate();
    
            Map<String, Object> keyMap = new HashMap<>();
            keyMap.put(PUBLIC_KEY, publicKey);
            keyMap.put(PRIVATE_KEY, privateKey);
    
            return keyMap;
        }
    
        public static byte[] getSecretKey(byte[] publicKey, byte[] privateKey) throws Exception {
    
            KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
            X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(publicKey);
            PublicKey pubKey = keyFactory.generatePublic(x509KeySpec);
    
            PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(privateKey);
            PrivateKey priKey = keyFactory.generatePrivate(pkcs8KeySpec);
    
            KeyAgreement keyAgree = KeyAgreement.getInstance(keyFactory.getAlgorithm());
    
            keyAgree.init(priKey);
            keyAgree.doPhase(pubKey, true);
            SecretKey secretKey = keyAgree.generateSecret(SELECT_ALGORITHM);
            return secretKey.getEncoded();
        }
    
        public static byte[] getPublicKey(Map<String, Object> keyMap){
    
            Key key = (Key) keyMap.get(PUBLIC_KEY);
            return key.getEncoded();
        }
    
        public static byte[] getPrivateKey(Map<String, Object> keyMap){
    
            Key key = (Key) keyMap.get(PRIVATE_KEY);
            return key.getEncoded();
        }
    
    }

Test.java

package cn.it1995;
    
    import org.apache.commons.codec.binary.Base64;
    
    import java.util.Map;
    
    public class Test {
    
        private static byte[] publicKey1;
        private static byte[] privateKey1;
        private static byte[] key1;
    
        private static byte[] publicKey2;
        private static byte[] privateKey2;
        private static byte[] key2;
    
        public static void main(String[] args) throws Exception {
    
            System.getProperties().setProperty("jdk.crypto.KeyAgreement.legacyKDF", "true");
    
            //服务端密钥
            Map<String, Object> keyMap1 = DH.initKey();
            publicKey1 = DH.getPublicKey(keyMap1);
            privateKey1 = DH.getPrivateKey(keyMap1);
            System.out.println("服务端公钥:" + Base64.encodeBase64String(publicKey1));
            System.out.println("服务端私钥:" + Base64.encodeBase64String(privateKey1));
    
            //客户端密钥
            Map<String, Object> keyMap2 = DH.initKey();
            publicKey2 = DH.getPublicKey(keyMap2);
            privateKey2 = DH.getPrivateKey(keyMap2);
            System.out.println("客户端公钥:" + Base64.encodeBase64String(publicKey2));
            System.out.println("客户端私钥:" + Base64.encodeBase64String(privateKey2));
    
            //服务端公钥和客户端私钥生成密钥
            key1 = DH.getSecretKey(publicKey1, privateKey2);
            System.out.println("客户端计算出的AES密钥:" + Base64.encodeBase64String(key1));
    
            //客户端公钥和服务端私钥生成密钥
            key2 = DH.getSecretKey(publicKey2, privateKey1);
            System.out.println("服务端计算出的AES密钥:" + Base64.encodeBase64String(key2));
    
            //开始进行加密
            String string = "Hello world, 中文";
            byte[] encrypt = DataSecret.encrypt(string.getBytes(), key1);
            byte[] decrypt = DataSecret.decrypt(encrypt, key2);
    
            System.out.println("原文:" + string);
            System.out.println("密文:" + new String(encrypt));
            System.out.println("解密:" + new String(decrypt));
        }
    }

[watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBASVQxOTk1_size_20_color_FFFFFF_t_70_g_se_x_16]: /images/20220829/7764ae17a00747a5a241246b754320b1.png
[watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBASVQxOTk1_size_12_color_FFFFFF_t_70_g_se_x_16]: /images/20220829/07fa627b706742b99a21b392d6cb5a74.png