DES和RSA混合加密及解密

实际开发过程中，RSA生成的公钥应保存在加密方，私钥应保存在解密方，可使用读取文件内容方式获取密钥。

maven依赖：

<!-- DES --><dependency><groupId>javax.xml.rpc</groupId><artifactId>javax.xml.rpc-api</artifactId><version>1.1.1</version></dependency><!-- RSA --><dependency><groupId>org.apache.axis</groupId><artifactId>axis</artifactId><version>1.4</version></dependency><!-- base64 --><dependency><groupId>commons-codec</groupId><artifactId>commons-codec</artifactId><version>1.10</version></dependency>

DES工具类：

package common;import javax.crypto.Cipher;import javax.crypto.KeyGenerator;import javax.crypto.SecretKey;import javax.crypto.SecretKeyFactory;import javax.crypto.spec.DESKeySpec;import javax.crypto.spec.IvParameterSpec;import java.security.NoSuchAlgorithmException;/*** @program: Demo* @Date: /2/20 20:59* @Author: LiJc* @Description:*/public class DESUtil {/*** 生成KEY*/public static byte[] getKey(){KeyGenerator keyGenerator = null;try {keyGenerator = KeyGenerator.getInstance("DES");} catch (NoSuchAlgorithmException e) {e.printStackTrace();System.out.println("----------------KEY生成失败！");return null;}keyGenerator.init(56);SecretKey secretKey = keyGenerator.generateKey();byte[] byteKey = secretKey.getEncoded();return byteKey;}/*** DES加密** @param context* @return*/public static byte[] desEncrypt(String context, String key) {try {// KEY转换DESKeySpec desKeySpec = new DESKeySpec(key.getBytes("UTF-8"));SecretKeyFactory secretKeyFactory = SecretKeyFactory.getInstance("DES");SecretKey conventSecretKey = secretKeyFactory.generateSecret(desKeySpec);// 加密Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");cipher.init(Cipher.ENCRYPT_MODE, conventSecretKey, new IvParameterSpec(key.getBytes("UTF-8")));return cipher.doFinal(context.getBytes("UTF-8"));} catch (Throwable e) {e.printStackTrace();return null;}}/*** DES解密** @param context* @return*/public static byte[] desDecrypt(byte[] context, String key) {try {// KEY转换DESKeySpec desKeySpec = new DESKeySpec(key.getBytes("UTF-8"));SecretKeyFactory secretKeyFactory = SecretKeyFactory.getInstance("DES");SecretKey conventSecretKey = secretKeyFactory.generateSecret(desKeySpec);// 解密Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");cipher.init(Cipher.DECRYPT_MODE, conventSecretKey, new IvParameterSpec(key.getBytes("UTF-8")));return cipher.doFinal(context);} catch (Throwable e) {e.printStackTrace();return null;}}}

RSA工具类：

package common;import mons.codec.binary.Base64;import mons.io.IOUtils;import javax.crypto.Cipher;import java.io.BufferedWriter;import java.io.ByteArrayOutputStream;import java.io.FileWriter;import java.security.*;import java.security.interfaces.RSAPrivateKey;import java.security.interfaces.RSAPublicKey;import java.security.spec.InvalidKeySpecException;import java.security.spec.PKCS8EncodedKeySpec;import java.security.spec.X509EncodedKeySpec;/*** @program: Demo* @Date: /2/21 22:56* @Author: LiJc* @Description:*/public class RSAUtil {/*** 转密钥字符串（base64编码）** @return*/public static String getKeyString(Key key) throws Exception {byte[] keyBytes = key.getEncoded();String s = new String(Base64.encodeBase64(keyBytes));return s;}/*** 得到公钥* @param publicKey 密钥字符串（经过base64编码）* @throws Exception*/public static RSAPublicKey getPublicKey(String publicKey) throws NoSuchAlgorithmException, InvalidKeySpecException {//通过X509编码的Key指令获得公钥对象KeyFactory keyFactory = KeyFactory.getInstance("RSA");X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(Base64.decodeBase64(publicKey));RSAPublicKey key = (RSAPublicKey) keyFactory.generatePublic(x509KeySpec);return key;}/*** 得到私钥* @param privateKey 密钥字符串（经过base64编码）* @throws Exception*/public static RSAPrivateKey getPrivateKey(String privateKey) throws NoSuchAlgorithmException, InvalidKeySpecException {//通过PKCS#8编码的Key指令获得私钥对象KeyFactory keyFactory = KeyFactory.getInstance("RSA");PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(Base64.decodeBase64(privateKey));RSAPrivateKey key = (RSAPrivateKey) keyFactory.generatePrivate(pkcs8KeySpec);return key;}/*** 生成密钥对* @param pubfilePath 公钥存放的文件路径* @param prifilePath 私钥存放的文件路径*/public static void genKeyPair(String pubfilePath, String prifilePath) {// KeyPairGenerator类用于生成公钥和私钥对，基于RSA算法生成对象KeyPairGenerator keyPairGen = null;try {keyPairGen = KeyPairGenerator.getInstance("RSA");} catch (NoSuchAlgorithmException e) {e.printStackTrace();}// 初始化密钥对生成器，密钥大小为96-1024位keyPairGen.initialize(1024, new SecureRandom());// 生成一个密钥对，保存在keyPair中KeyPair keyPair = keyPairGen.generateKeyPair();// 得到私钥RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();// 得到公钥RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();try {// 得到公钥字符串String publicKeyString = getKeyString(publicKey);// 得到私钥字符串String privateKeyString = getKeyString(privateKey);// 将密钥对写入到文件FileWriter pubfw = new FileWriter(pubfilePath);FileWriter prifw = new FileWriter(prifilePath);BufferedWriter pubbw = new BufferedWriter(pubfw);BufferedWriter pribw = new BufferedWriter(prifw);pubbw.write(publicKeyString);pribw.write(privateKeyString);pubbw.flush();pubbw.close();pubfw.close();pribw.flush();pribw.close();prifw.close();} catch (Exception e) {e.printStackTrace();}}/*** 公钥加密* @param data需要加密的内容* @param publicKey公钥* @return*/public static String publicEncrypt(String data, RSAPublicKey publicKey){try{Cipher cipher = Cipher.getInstance("RSA");cipher.init(Cipher.ENCRYPT_MODE, publicKey);return new String(Base64.encodeBase64(rsaSplitCodec(cipher, Cipher.ENCRYPT_MODE, data.getBytes("UTF-8"), publicKey.getModulus().bitLength())));}catch(Exception e){throw new RuntimeException("加密字符串[" + data + "]时遇到异常", e);}}/*** 私钥解密* @param data需要加密的内容* @param privateKey私钥* @return*/public static String privateDecrypt(String data, RSAPrivateKey privateKey){try{Cipher cipher = Cipher.getInstance("RSA");cipher.init(Cipher.DECRYPT_MODE, privateKey);return new String(rsaSplitCodec(cipher, Cipher.DECRYPT_MODE, Base64.decodeBase64(data), privateKey.getModulus().bitLength()), "UTF-8");}catch(Exception e){throw new RuntimeException("解密字符串[" + data + "]时遇到异常", e);}}private static byte[] rsaSplitCodec(Cipher cipher, int opmode, byte[] datas, int keySize){int maxBlock = 0;if(opmode == Cipher.DECRYPT_MODE){maxBlock = keySize / 8;}else{maxBlock = keySize / 8 - 11;}ByteArrayOutputStream out = new ByteArrayOutputStream();int offSet = 0;byte[] buff;int i = 0;try{while(datas.length > offSet){if(datas.length-offSet > maxBlock){buff = cipher.doFinal(datas, offSet, maxBlock);}else{buff = cipher.doFinal(datas, offSet, datas.length-offSet);}out.write(buff, 0, buff.length);i++;offSet = i * maxBlock;}}catch(Exception e){throw new RuntimeException("加解密阀值为["+maxBlock+"]的数据时发生异常", e);}byte[] resultDatas = out.toByteArray();IOUtils.closeQuietly(out);return resultDatas;}}

单元测试：

注意：RSA用到的密钥对为上一篇文章生成的 /JcMR_Li/article/details/87873079

package common;import mons.codec.binary.Base64;import org.junit.Test;import java.security.NoSuchAlgorithmException;import java.security.interfaces.RSAPrivateKey;import java.security.interfaces.RSAPublicKey;import java.security.spec.InvalidKeySpecException;/*** @program: Demo* @Date: /2/22 10:18* @Author: LiJc* @Description:*/public class DESAndRSATest {/*** DES和RSA混合加密，先进行DES加密，将DES加密后的内容进行base64编码，再将base64编码的DES进行RSA加密*/@Testpublic void test1() throws InvalidKeySpecException, NoSuchAlgorithmException {String deskey = "password";//des密钥//长度8位String content = "真香警告！"; //内容System.out.println("原始加密内容为："+content);//DES加密byte[] encryptbyte = DESUtil.desEncrypt(content, deskey); //加密后返回为字节数组String descontent = Base64.encodeBase64String(encryptbyte);System.out.println("DES加密后内容为："+ descontent);//RSA部分startString pubkey = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCQ1IqhPNo8M/R1pHpocNuJ6enntJoB7OAaJrVoaHbvJOI4APkheX0J1UKizOGQNRr/V6vp3B+3MrPVGJ4lfRirrgnIK86PD5K/MChSWhxslWf3jQxr7AO8rMIPre7uoGjmY3pbSY82QUGDEhgDVsWTLTjWWqFQHVTwEfBPGgaktQIDAQAB";//根据公钥key获取公钥RSAPublicKey publicKey = RSAUtil.getPublicKey(pubkey);//RSA加密String rsacontent = RSAUtil.publicEncrypt(descontent, publicKey);System.out.println("RSA加密后内容为："+rsacontent);String prikey = "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";//获取私钥RSAPrivateKey privateKey = RSAUtil.getPrivateKey(prikey);//RSA解密String content1 = RSAUtil.privateDecrypt(rsacontent, privateKey);System.out.println("RSA解密后内容为："+content1);//RSA部分end//DES解密byte[] decryptbyte = DESUtil.desDecrypt(Base64.decodeBase64(content1), deskey); //将加密后返回的字节数组进行解密System.out.println("DES解密后内容为："+ new String(decryptbyte));}}

测试结果：