关于DES和RSA各自单独加密的弊端大家自行学习吧，本文使用对称式加密算法DES和非对称式加密算法RSA结合做数据加密的方式，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，本文分别创建DES和RSA工具类，便于单独使用，也可混合使用。具体步骤如下：
1、POM文件添加相关jar包
<!-- 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>
2、自定义一个DES密钥，最好是8位，放在配置文件里面
3、生成一对RSA公钥和私钥，也放在配置文件里面
生成代码：
/*** 生成RSA密钥对*/protected static Map<String, String> genKeyPairMap() {Map<String, String> keyPairMap = new HashMap<>(2);// 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");// 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();// 得到公钥字符串String publicKeyString = getKeyString(publicKey);// 得到私钥字符串String privateKeyString = getKeyString(privateKey);keyPairMap.put("publicKey", publicKeyString);keyPairMap.put("privateKey", privateKeyString);} catch (Exception e) {logger.error("[RsaUtil]-生成密钥对失败！ ---------------", e);throw new PlatException("[RsaUtil]-生成密钥对失败！");}return keyPairMap;}
配置文件
desKey = dev-RSA_public_key = MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDylxBFYYsoc9sfyWJ9sdWlsJj13aOcqDhaX5FLAyZP4mz7Jz4cGzDQkY1iGBKHl5NC24dD0f7y1KUncE/8qAgoPiX1T5uK6CC5d/AxLK+ElrhiTp+mtkuGZKAQ9oO+bzqNMH0yP80LXVGXQlIOPjP5/lduG+X1JwsOLyCpPvhCTQIDAQABRSA_private_key = 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
4、创建DES加解密工具类
import java.security.interfaces.RSAPrivateKey;import java.security.interfaces.RSAPublicKey;/*** @author qigc* @Description ES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* @createTime 08月23日 15:42:00*/public class DEUtil {private static final Logger logger = LoggerFactory.getLogger(DEUtil.class);/*** 编码格式*/private static final String DES_KEY = "desKey";private static final String PUBLIC_KEY = "RSA_public_key";private static final String PRIVATE_KEY = "RSA_private_key";/*** 加密** @param content 加密内容* @return*/public static String encrypt(String content) {String rsaContent = null;try {//从配置文件获取des密钥8位String desKey = PlatApplicationContext.getProperties(DES_KEY);//DES加密String desContent = DesUtil.encrypt(content, desKey);//从配置文件获取公钥keyString pubKey = PlatApplicationContext.getProperties(PUBLIC_KEY);//根据公钥key获取公钥RSAPublicKey publicKey = RsaUtil.getPublicKey(pubKey);//RSA加密rsaContent = RsaUtil.publicEncrypt(desContent, publicKey);} catch (Exception e) {logger.error("[DEUtil]-加密失败！ ---------------", e);throw new PlatException("[DEUtil]-加密失败！");}return rsaContent;}/*** @return java.lang.String* @author qigc* 解密* @date /8/23*/public static String decode(String rsaContent) {String content = null;try {//从配置文件获取des密钥8位String desKey = PlatApplicationContext.getProperties(DES_KEY);String priKey = PlatApplicationContext.getProperties(PRIVATE_KEY);//获取私钥RSAPrivateKey privateKey = RsaUtil.getPrivateKey(priKey);//RSA解密String contentRsa = RsaUtil.privateDecryptToString(rsaContent,privateKey);//DES解密content = DesUtil.decrypt(contentRsa,desKey);} catch (Exception e) {logger.error("[DEUtil]-解密失败！ ---------------", e);throw new PlatException("[DEUtil]-解密失败！");}return content;}}
5、创建RSA加密解密工具类RsaUtil
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;import java.util.HashMap;import java.util.Map;/*** @author qigc* @Description RSA工具类* @createTime 08月23日 15:14:00*/class RsaUtil {private static final Logger logger = LoggerFactory.getLogger(RsaUtil.class);/*** 编码格式*/private static final String E_CODE_TYPE = "UTF-8";/*** 转密钥字符串（base64编码）** @return*/private static String getKeyString(Key key) throws Exception {byte[] keyBytes = key.getEncoded();return new String(Base64.encodeBase64(keyBytes));}/*** 得到公钥** @param publicKey 密钥字符串（经过base64编码）* @throws Exception*/protected 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));return (RSAPublicKey) keyFactory.generatePublic(x509KeySpec);}/*** 得到私钥** @param privateKey 密钥字符串（经过base64编码）* @throws Exception*/protected 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));return (RSAPrivateKey) keyFactory.generatePrivate(pkcs8KeySpec);}/*** 公钥加密** @param data需要加密的内容* @param publicKey 公钥* @return*/protected 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(E_CODE_TYPE), publicKey.getModulus().bitLength())));} catch (Exception e) {logger.error("[RsaUtil]-公钥加密失败！ ---------------", 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*/protected static String privateDecryptToString(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()), E_CODE_TYPE);} catch (Exception e) {logger.error("[RsaUtil]-私钥解密失败！ ---------------", e);throw new RuntimeException("解密字符串[" + 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*/protected static byte[] privateDecrypt(String data, RSAPrivateKey privateKey) {try {Cipher cipher = Cipher.getInstance("RSA");cipher.init(Cipher.DECRYPT_MODE, privateKey);return rsaSplitCodec(cipher, Cipher.DECRYPT_MODE, Base64.decodeBase64(data), privateKey.getModulus().bitLength());} catch (Exception e) {logger.error("[RsaUtil]-私钥解密失败！ ---------------", 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) {logger.error("[RsaUtil]-加解密失败！ ---------------", 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;}}
6、创建DES+RSA混合加解密工具类DEUtil
import java.security.interfaces.RSAPrivateKey;import java.security.interfaces.RSAPublicKey;/*** @author qigc* @Description ES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* @createTime 08月23日 15:42:00*/public class DEUtil {private static final Logger logger = LoggerFactory.getLogger(DEUtil.class);/*** 编码格式*/private static final String DES_KEY = "desKey";private static final String PUBLIC_KEY = "RSA_public_key";private static final String PRIVATE_KEY = "RSA_private_key";/*** 加密** @param content 加密内容* @return*/public static String encrypt(String content) {String rsaContent = null;try {//从配置文件获取des密钥8位String desKey = PlatApplicationContext.getProperties(DES_KEY);//DES加密String desContent = DesUtil.encrypt(content, desKey);//从配置文件获取公钥keyString pubKey = PlatApplicationContext.getProperties(PUBLIC_KEY);//根据公钥key获取公钥RSAPublicKey publicKey = RsaUtil.getPublicKey(pubKey);//RSA加密rsaContent = RsaUtil.publicEncrypt(desContent, publicKey);} catch (Exception e) {logger.error("[DEUtil]-加密失败！ ---------------", e);throw new PlatException("[DEUtil]-加密失败！");}return rsaContent;}/*** @return java.lang.String* @author qigc* 解密* @date /8/23*/public static String decode(String rsaContent) {String content = null;try {//从配置文件获取des密钥8位String desKey = PlatApplicationContext.getProperties(DES_KEY);String priKey = PlatApplicationContext.getProperties(PRIVATE_KEY);//获取私钥RSAPrivateKey privateKey = RsaUtil.getPrivateKey(priKey);//RSA解密String contentRsa = RsaUtil.privateDecryptToString(rsaContent,privateKey);//DES解密content = DesUtil.decrypt(contentRsa,desKey);} catch (Exception e) {logger.error("[DEUtil]-解密失败！ ---------------", e);throw new PlatException("[DEUtil]-解密失败！");}return content;}}
