javaRSAUtils加密⼯具类操作1.RSA加密算法是⼀种⾮对称加密算法。
在公开密钥加密和电⼦商业中RSA被⼴泛使⽤。
RSA公开密钥密码体制。
所谓的公开密钥密码体制就是使⽤不同的加密密钥与解密密钥，是⼀种“由已知加密密钥推导出解密密钥在计算上是不可⾏的”密码体制。
在公开密钥密码体制中，加密密钥（即公开密钥）PK是公开信息，⽽解密密钥（即秘密密钥）SK是需要保密的。
加密算法E和解密算法D也都是公开的。
虽然解密密钥SK是由公开密钥PK决定的，但却不能根据PK计算出SK。
2.本⼯具类涉及到BASE64编码，所以先展⽰出BASE64Utils：package mon.util;import sun.misc.BASE64Decoder;import sun.misc.BASE64Encoder;import java.security.MessageDigest;/*** BASE64的加解密* @author Neo* @date 2018-4-15 22:21:51**/@SuppressWarnings("restriction")public class Base64Utils {public static final String KEY_SHA = "SHA";public static final String KEY_MD5 = "MD5";/*** BASE64解密** @param key* @return* @throws Exception*/public static byte[] decryptBASE64(String key) throws Exception {return (new BASE64Decoder()).decodeBuffer(key);}/*** BASE64加密** @param key* @return* @throws Exception*/public static String encryptBASE64(byte[] key) throws Exception {return (new BASE64Encoder()).encodeBuffer(key);}/*** MD5加密** @param data* @return* @throws Exception*/public static byte[] encryptMD5(byte[] data) throws Exception {MessageDigest md5 = MessageDigest.getInstance(KEY_MD5);md5.update(data);return md5.digest();}/*** SHA加密** @param data* @return* @throws Exception*/public static byte[] encryptSHA(byte[] data) throws Exception {MessageDigest sha = MessageDigest.getInstance(KEY_SHA);sha.update(data);return sha.digest();}}3.然后我们展⽰RSAUtils：package mon.util;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.X509EncodedKeySpec;import java.util.HashMap;import java.util.Map;/*** RSA安全编码组件** @version 1.0* @desc 公钥和私钥存放在properties⽂件的时候每⾏的末尾加上“\r\n\” <br/>* “\r\n” 起到换⾏的作⽤,最后的“\”在properties在⾥表⽰连接** @author Neo* @date 2018-4-15 22:23:19* @since 1.0*/public class RSAUtils extends Base64Utils {public static final String KEY_ALGORITHM = "RSA";public static final String SIGNATURE_ALGORITHM = "MD5withRSA";private static final String PUBLIC_KEY = "RSAPublicKey";private static final String PRIVATE_KEY = "RSAPrivateKey";/*** ⽤私钥对信息⽣成数字签名** @param data 加密数据* @param privateKey 私钥* @return* @throws Exception*/public static String sign(String data, String privateKey) throws Exception {return sign(data.getBytes(), privateKey);}/*** ⽤私钥对信息⽣成数字签名** @param data 加密数据* @param privateKey 私钥* @return* @throws Exception*/public static String sign(byte[] data, String privateKey) throws Exception {// 解密由base64编码的私钥byte[] keyBytes = decryptBASE64(privateKey);// 构造PKCS8EncodedKeySpec对象PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes); // KEY_ALGORITHM 指定的加密算法KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);// 取私钥匙对象PrivateKey priKey = keyFactory.generatePrivate(pkcs8KeySpec);// ⽤私钥对信息⽣成数字签名Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);signature.initSign(priKey);signature.update(data);return encryptBASE64(signature.sign());/*** 校验数字签名** @param data 加密数据* @param publicKey 公钥* @param sign 数字签名* @return 校验成功返回true 失败返回false* @throws Exception*/public static boolean verify(String data, String publicKey, String sign) throws Exception { return verify(data.getBytes(), publicKey, sign);}/*** 校验数字签名** @param data 加密数据* @param publicKey 公钥* @param sign 数字签名* @return 校验成功返回true 失败返回false* @throws Exception*/public static boolean verify(byte[] data, String publicKey, String sign) throws Exception { // 解密由base64编码的公钥byte[] keyBytes = decryptBASE64(publicKey);// 构造X509EncodedKeySpec对象X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);// KEY_ALGORITHM 指定的加密算法KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);// 取公钥匙对象PublicKey pubKey = keyFactory.generatePublic(keySpec);Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);signature.initVerify(pubKey);signature.update(data);// 验证签名是否正常return signature.verify(decryptBASE64(sign));}/*** 解密<br>* ⽤私钥解密** @param data* @param key* @return* @throws Exception*/public static String decryptByPrivateKey(String data, String key) throws Exception {return new String(decryptByPrivateKey(Base64Utils.decryptBASE64(data), key));}/*** 解密<br>* ⽤私钥解密** @param data* @param key* @return* @throws Exception*/public static byte[] decryptByPrivateKey(byte[] data, String key) throws Exception {// 对密钥解密byte[] keyBytes = decryptBASE64(key);// 取得私钥PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes); KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);Key privateKey = keyFactory.generatePrivate(pkcs8KeySpec);// 对数据解密Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());cipher.init(Cipher.DECRYPT_MODE, privateKey);return cipher.doFinal(data);}/*** 解密<br>* ⽤私钥解密** @param data* @param key* @return* @throws Exception*/public static String decryptByPublicKey(String data, String key) throws Exception { return new String(decryptByPublicKey(Base64Utils.decryptBASE64(data), key)); }/*** 解密<br>* ⽤私钥解密** @param data* @param key* @return* @throws Exception*/public static byte[] decryptByPublicKey(byte[] data, String key) throws Exception { // 对密钥解密byte[] keyBytes = decryptBASE64(key);// 取得公钥X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes); KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);Key publicKey = keyFactory.generatePublic(x509KeySpec);// 对数据解密Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());cipher.init(Cipher.DECRYPT_MODE, publicKey);return cipher.doFinal(data);}/*** 加密<br>* ⽤公钥加密** @param data* @param key* @return* @throws Exception*/public static String encryptByPublicKey(String data, String key) throws Exception { return Base64Utils.encryptBASE64(encryptByPublicKey(data.getBytes(), key)); }/*** 加密<br>* ⽤公钥加密** @param data* @param key* @return* @throws Exception*/public static byte[] encryptByPublicKey(byte[] data, String key) throws Exception { // 对公钥解密byte[] keyBytes = decryptBASE64(key);// 取得公钥X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes); KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);Key publicKey = keyFactory.generatePublic(x509KeySpec);// 对数据加密Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());cipher.init(Cipher.ENCRYPT_MODE, publicKey);return cipher.doFinal(data);}/*** 加密<br>* ⽤私钥加密** @param data* @param key* @return* @throws Exception*/public static String encryptByPrivateKey(String data, String key) throws Exception { return Base64Utils.encryptBASE64(encryptByPrivateKey(data.getBytes(), key)); }/*** 加密<br>* ⽤私钥加密** @param data* @param key* @return* @throws Exception*/public static byte[] encryptByPrivateKey(byte[] data, String key) throws Exception { // 对密钥解密byte[] keyBytes = decryptBASE64(key);// 取得私钥PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes); KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);Key privateKey = keyFactory.generatePrivate(pkcs8KeySpec);// 对数据加密Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());cipher.init(Cipher.ENCRYPT_MODE, privateKey);return cipher.doFinal(data);}/*** 取得私钥** @param keyMap* @return* @throws Exception*/public static String getPrivateKey(Map<String, Object> keyMap) throws Exception { Key key = (Key) keyMap.get(PRIVATE_KEY);return encryptBASE64(key.getEncoded());}/*** 取得公钥** @param keyMap* @return* @throws Exception*/public static String getPublicKey(Map<String, Object> keyMap) throws Exception {Key key = (Key) keyMap.get(PUBLIC_KEY);return encryptBASE64(key.getEncoded());}/*** 初始化密钥** @return* @throws Exception*/public static Map<String, Object> initKey() throws Exception {KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance(KEY_ALGORITHM); keyPairGen.initialize(1024);KeyPair keyPair = keyPairGen.generateKeyPair();// 公钥RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();// 私钥RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();Map<String, Object> keyMap = new HashMap<String, Object>(2);keyMap.put(PUBLIC_KEY, publicKey);keyMap.put(PRIVATE_KEY, privateKey);return keyMap;}public static void main(String[] args) {try {Map<String, Object> map = RSAUtils.initKey();String publicKey = RSAUtils.getPublicKey(map);String privateKey = RSAUtils.getPrivateKey(map);System.out.println("公钥：" + publicKey);System.out.println("私钥：" + privateKey);String data = "Java是世界上最好的编程语⾔";String encryptData = RSAUtils.encryptByPublicKey(data, publicKey);System.out.println("加密后：" + encryptData);String decryptData = RSAUtils.decryptByPrivateKey(encryptData, privateKey);System.out.println("解密后：" + decryptData);} catch (Exception e) {e.printStackTrace();}}}4.最后展⽰测试结果：补充知识：java使⽤RSA⽣成公钥和私钥，并进⾏加解密废话不多说，上代码：import javax.crypto.Cipher;import sun.misc.BASE64Decoder;import sun.misc.BASE64Encoder;import java.security.KeyFactory;import java.security.KeyPair;import java.security.KeyPairGenerator;import java.security.SecureRandom;import java.security.interfaces.RSAPrivateKey;import java.security.interfaces.RSAPublicKey;import java.security.spec.PKCS8EncodedKeySpec;import java.security.spec.X509EncodedKeySpec;import java.util.HashMap;import java.util.Map;/*** Java RSA 加密⼯具类*/public class RSAUtils {/*** 密钥长度于原⽂长度对应以及越长速度越慢*/private final static int KEY_SIZE = 1024;/*** ⽤于封装随机产⽣的公钥与私钥*/private static Map<Integer, String> keyMap = new HashMap<Integer, String>();/*** 随机⽣成密钥对* @throws Exception*/public static void genKeyPair() throws Exception {// KeyPairGenerator类⽤于⽣成公钥和私钥对，基于RSA算法⽣成对象KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance("RSA");// 初始化密钥对⽣成器keyPairGen.initialize(KEY_SIZE, 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();String publicKeyString = encryptBASE64(publicKey.getEncoded());// 得到私钥字符串String privateKeyString = encryptBASE64(privateKey.getEncoded());// 将公钥和私钥保存到Map//0表⽰公钥keyMap.put(0, publicKeyString);//1表⽰私钥keyMap.put(1, privateKeyString);}//编码返回字符串public static String encryptBASE64(byte[] key) throws Exception {return (new BASE64Encoder()).encodeBuffer(key);}//解码返回bytepublic static byte[] decryptBASE64(String key) throws Exception {return (new BASE64Decoder()).decodeBuffer(key);}/*** RSA公钥加密** @param str 加密字符串* @param publicKey 公钥* @return 密⽂* @throws Exception 加密过程中的异常信息*/public static String encrypt(String str, String publicKey) throws Exception {//base64编码的公钥byte[] decoded = decryptBASE64(publicKey);RSAPublicKey pubKey = (RSAPublicKey) KeyFactory.getInstance("RSA").generatePublic(new X509EncodedKeySpec(decoded)); //RSA加密Cipher cipher = Cipher.getInstance("RSA");cipher.init(Cipher.ENCRYPT_MODE, pubKey);String outStr = encryptBASE64(cipher.doFinal(str.getBytes("UTF-8")));return outStr;}/*** RSA私钥解密** @param str 加密字符串* @param privateKey 私钥* @return 明⽂* @throws Exception 解密过程中的异常信息*/public static String decrypt(String str, String privateKey) throws Exception {//64位解码加密后的字符串byte[] inputByte = decryptBASE64(str);//base64编码的私钥byte[] decoded = decryptBASE64(privateKey);RSAPrivateKey priKey = (RSAPrivateKey) KeyFactory.getInstance("RSA").generatePrivate(new PKCS8EncodedKeySpec(decoded));//RSA解密Cipher cipher = Cipher.getInstance("RSA");cipher.init(Cipher.DECRYPT_MODE, priKey);String outStr = new String(cipher.doFinal(inputByte));return outStr;}public static void main(String[] args) throws Exception {long temp = System.currentTimeMillis();//⽣成公钥和私钥genKeyPair();//加密字符串System.out.println("公钥:" + keyMap.get(0));System.out.println("私钥:" + keyMap.get(1));System.out.println("⽣成密钥消耗时间:" + (System.currentTimeMillis() - temp) / 1000.0 + "秒");String message = "RSA测试aaa";System.out.println("原⽂:" + message);temp = System.currentTimeMillis();String messageEn = encrypt(message, keyMap.get(0));System.out.println("密⽂:" + messageEn);System.out.println("加密消耗时间:" + (System.currentTimeMillis() - temp) / 1000.0 + "秒");temp = System.currentTimeMillis();String messageDe = decrypt(messageEn, keyMap.get(1));System.out.println("解密:" + messageDe);System.out.println("解密消耗时间:" + (System.currentTimeMillis() - temp) / 1000.0 + "秒");}}以上这篇java RSAUtils 加密⼯具类操作就是⼩编分享给⼤家的全部内容了，希望能给⼤家⼀个参考，也希望⼤家多多⽀持。
