开罐即用系列-RSA加密解密

向右看齐 2024-02-18 22:49 23阅读 0赞

用途：适用于少量数据的加密解密(RSA加密特点：安全性高、成熟度高、速度慢、资源消耗高)

第一步:工具类(2个)

RSA工具类

import javax.crypto.Cipher;
    import java.security.*;
    import java.security.spec.PKCS8EncodedKeySpec;
    import java.security.spec.X509EncodedKeySpec;
    
    /**
     * RSA工具类
     * @author szw
     * @version 1.0
     * @since JDK1.8
     */
    public class RSAUtil {
        private static KeyPair keyPair;
        private static String publicKeyStr;
        private static String privateKeyStr;
    
        public static String getPublicKeyStr() {
            return publicKeyStr;
        }
    
        public static void setPublicKeyStr(String publicKeyStr) {
            RSAUtil.publicKeyStr = publicKeyStr;
        }
    
        public static String getPrivateKeyStr() {
            return privateKeyStr;
        }
    
        public static void setPrivateKeyStr(String privateKeyStr) {
            RSAUtil.privateKeyStr = privateKeyStr;
        }
    
        static {
            try {
                keyPair = getKeyPair();
            } catch (Exception e) {
                e.printStackTrace();
            }
    
            publicKeyStr = getPublicKey();
            privateKeyStr = getPrivateKey();
        }
    
        /**
         * 生成密钥对
         * @return
         * @throws Exception
         */
        private static KeyPair getKeyPair() throws Exception {
            KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
            keyPairGenerator.initialize(2048);
            KeyPair keyPair = keyPairGenerator.generateKeyPair();
            return keyPair;
        }
    
        /**
         * 获取公钥(Base64编码)
         * @return
         */
        private static String getPublicKey(){
            PublicKey publicKey = keyPair.getPublic();
            byte[] bytes = publicKey.getEncoded();
            return Base64Util.byteToBase64(bytes);
        }
    
        /**
         * 获取私钥(Base64编码)
         * @return
         */
        private static String getPrivateKey(){
            PrivateKey privateKey = keyPair.getPrivate();
            byte[] bytes = privateKey.getEncoded();
            return Base64Util.byteToBase64(bytes);
        }
    
    
        /**
         * 公钥加密
         * 加密后的内容经过了base64转码
         * @param msg
         * @return
         * @throws Exception
         */
        public static String publicEncrypt(String msg) throws Exception{
            byte[] content = msg.getBytes();
            byte[] keyBytes = Base64Util.base64ToBytes(publicKeyStr);
            X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            PublicKey publicKey = keyFactory.generatePublic(keySpec);
    
            Cipher cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.ENCRYPT_MODE, publicKey);
            byte[] bytes = cipher.doFinal(content);
            return Base64Util.byteToBase64(bytes);
        }
    
        /**
         * 私钥解密
         *
         * @param publicEncrypt 经过base64转码的密文
         * @return
         * @throws Exception
         */
        public static String privateDecrypt(String publicEncrypt) throws Exception{
            byte[] content = Base64Util.base64ToBytes(publicEncrypt);
            byte[] keyBytes = Base64Util.base64ToBytes(privateKeyStr);
            PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(keyBytes);
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            PrivateKey privateKey = keyFactory.generatePrivate(keySpec);
    
            Cipher cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.DECRYPT_MODE, privateKey);
            byte[] bytes = cipher.doFinal(content);
            return new String(bytes);
        }
    
    }

base64工具类

import sun.misc.BASE64Decoder;
    import sun.misc.BASE64Encoder;
    import java.io.IOException;
    
    /**
     * base64工具类
     * @author szw
     * @version 1.0
     * @since JDK1.8
     */
    public class Base64Util {
    
        /**
         * 将字节码转换成base64
         *
         * @param bytes
         * @return
         */
        public static String byteToBase64(byte[] bytes) {
            BASE64Encoder base64Encoder = new BASE64Encoder();
            return base64Encoder.encode(bytes);
        }
    
        /**
         * 将base64转换成字节码
         * @param base64
         * @return
         * @throws IOException
         */
        public static byte[] base64ToBytes(String base64) throws IOException {
            BASE64Decoder base64Decoder = new BASE64Decoder();
            return base64Decoder.decodeBuffer(base64);
        }
    }

使用方式:

用工具类生成RSA密钥对保存起来:

String publicKeyStr = RSAUtil.getPublicKeyStr();
    String privateKeyStr = RSAUtil.getPrivateKeyStr();

使用密钥对进行加密解密:

/**
     * 
     * @author sunziwen
     * 2018-08-13 11:04
     * @version 1.0
     **/
    public class Main {
        public static void main(String args[]) throws Exception {
            String publicKeyStr = "MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA5t9yr2YPa/Cmy2gUbItLxmSpkizcTH0z\n" +
                    "YnBZ7x3n07HNuRPAe215tZtodfSoz9GxpLKgn9HrKan5zQN6ESJ2U21evcY0VZjWYMBY0X9oJNQq\n" +
                    "FQyZwYVH78//yYzcDyZejVy54/SFeWUwv89Gy155I96ao0pao4CJh16sf/b7H60+idzmmye/o9PK\n" +
                    "5JiiOSGEaNyMFFlmg11gTrBqHN/7PAHNc6V22a9GpMeKfO7qEljBEyfzgkxhC6JP1dOOqIS9iBRg\n" +
                    "wIymZxYWQaRhVfhniRYQZKQYBr3uZ6zRi/np7C8M8TWK3riHey5y/U868XELzdAmgwFJz3mjcnZJ\n" +
                    "Rze6SwIDAQAB";
            String privateKeyStr = "MIIEvgIBADANBgkqhkiG9w0BAQEFAASCBKgwggSkAgEAAoIBAQDm33KvZg9r8KbLaBRsi0vGZKmS\n" +
                    "LNxMfTNicFnvHefTsc25E8B7bXm1m2h19KjP0bGksqCf0espqfnNA3oRInZTbV69xjRVmNZgwFjR\n" +
                    "f2gk1CoVDJnBhUfvz//JjNwPJl6NXLnj9IV5ZTC/z0bLXnkj3pqjSlqjgImHXqx/9vsfrT6J3Oab\n" +
                    "J7+j08rkmKI5IYRo3IwUWWaDXWBOsGoc3/s8Ac1zpXbZr0akx4p87uoSWMETJ/OCTGELok/V046o\n" +
                    "hL2IFGDAjKZnFhZBpGFV+GeJFhBkpBgGve5nrNGL+ensLwzxNYreuId7LnL9TzrxcQvN0CaDAUnP\n" +
                    "eaNydklHN7pLAgMBAAECggEBAJLhCXdpONp1CchSeNvtatHW7MKgY68N4Aj6bVzg68IUVksus8BS\n" +
                    "j6HoMvcIJfXA9IFRWzsSM8gX6WJymdAY2qqM5D9bv6PNTmXTOS5fHgSALh2iHJevkWqSK6swQDgr\n" +
                    "MvBAU8sgn2Hx7Ke62NE9U1hsoHjOLwfiGJzUsG3g1Tb6rWrKz+fyVBtwQE0GwsWPKpft1XfSuTNg\n" +
                    "c8Jh+//wXqyn+k+MgTmdstnHb7zfhPC5CSzmhmuZLl68ry1HaFvPjQpAmcKjVKIgK+qkb2+RYz84\n" +
                    "XHl2PInN3rggNmfP6lD8TF8i53BIv3ziksaITk4YK1AfLKb6Wjt7A1gCgoq9A1ECgYEA+KWd1vUo\n" +
                    "0OM466CKioJD7/VSOvVR2QAdS3TiWclUVWjL6lOTBhJf0Y8oK9xy3+XNykwKF2YoFpkIikO5dX7l\n" +
                    "NZTwJ2J66Ij006ocYlWtyUcBgJCIt7QTGSdxnvDdt25x1UXXbch2PaH7P4OPhdlWkeckJyQ0hycY\n" +
                    "m3ktoEm5/dUCgYEA7bNFwv4KpbmXRpTZvpWi6uuDQnYIH6fb5Qozp0WbAZY2RjPpUpGz54loiusz\n" +
                    "RRqdP9sr79GIARAuxvJAFRcnmZKcbrEQEFSzO0fFVX0f1HIfMrkce0Cpk8Y2RSkmeYmSvr1vlZ6d\n" +
                    "QnuTzBV9HtJvtwQ9LbbBQkjCffQEQeeZR58CgYEAyaaXMaO1rGL64K1cbiRjMJJGVCZscI6VM4Lh\n" +
                    "p2uOB45sAegxjnUMXIm7TIcGauqWUQAGFx/0Vw9ZS7jNCasV/LSDZ42InFmmJJsLVfyiamA5qaiO\n" +
                    "GF3kNzwz+3Dgf0kE7LAtnI08x5M8jjAGD8lJWh6YxV2pdAqS/FP0WtAwFNkCgYAmEKJoUoRj+6+F\n" +
                    "BwtDoPThB+wSNZKhdyEYsaSJ8fSbsXFplqCTr2+O8YtDS9z/AP8TncaQdg6AlRXYmCy48+dMiZTx\n" +
                    "iPtYkifNo3WvdgUl4Uyrs8ci2b0ORBymwKs/pU9RqkZ3QFpQrjeB5CMQT4TCWzRs4KpcMgirYOtZ\n" +
                    "nnwGYwKBgEmmGl5KHjeDvZx+WkYOV+LXzsvVaBxHFE/LFHD5srcoeSW2dyBK8q+RXwpFQsmh9Q58\n" +
                    "ARb/hyWZ70V+XeTRKPPt9B4nYu1s40liZGFAf5Dutd7aDWL7H8FlBYhYa9u1wv4x5YtRKItNvwl6\n" +
                    "G8id3M/BPGsJrOJrmhhFyOTiJc/V";
            /**
             * 待加密数据
             */
            String msg = "身先士卒";
            RSAUtil.setPublicKeyStr(publicKeyStr);
            RSAUtil.setPrivateKeyStr(privateKeyStr);
            /**
             * 公钥加密
             */
            String publicEncrypt = RSAUtil.publicEncrypt(msg);
            /**
             * 私钥解密
             */
            String privateDecrypt = RSAUtil.privateDecrypt(publicEncrypt);
        }
    
    }