AES 和RSA加解密

AES 加解密

public class AESUtil {

    private static final String KEY_ALGORITHM = "AES";
    private static final String DEFAULT_CIPHER_ALGORITHM = "AES/ECB/PKCS5Padding";//默认的加密算法

    /**
     * AES 加密操作
     *
     * @param content 待加密内容
     * @param key 加密密钥
     * @return 返回Base64转码后的加密数据
     */
    public static String encrypt(String content, String key) {
        try {
            Cipher cipher = Cipher.getInstance(DEFAULT_CIPHER_ALGORITHM);// 创建密码器
            byte[] byteContent = content.getBytes(StandardCharsets.UTF_8);
            cipher.init(Cipher.ENCRYPT_MODE, getSecretKey(key));// 初始化为加密模式的密码器
            byte[] result = cipher.doFinal(byteContent);// 加密
            return new String(Base64.encode(result, Base64.NO_WRAP));//通过Base64转码返回
        } catch (Exception ex) {
            Logger.getLogger(AESUtil.class.getName()).log(Level.SEVERE, null, ex);
        }

        return null;
    }

    /**
     * AES 解密操作
     *
     * @param content
     * @param key
     * @return
     */
    public static String decrypt(String content, String key) {

        try {
            //实例化
            Cipher cipher = Cipher.getInstance(DEFAULT_CIPHER_ALGORITHM);
            //使用密钥初始化，设置为解密模式
            cipher.init(Cipher.DECRYPT_MODE, getSecretKey(key));
            //执行操作
            byte[] result = cipher.doFinal(Base64.decode(content, Base64.NO_WRAP));
            return new String(result, StandardCharsets.UTF_8);
        } catch (Exception ex) {
            Logger.getLogger(AESUtil.class.getName()).log(Level.SEVERE, null, ex);
        }

        return null;
    }


    private static SecretKeySpec getSecretKey(final String key) {
        //返回生成指定算法密钥生成器的 KeyGenerator 对象
        return new SecretKeySpec(key.getBytes(), DEFAULT_CIPHER_ALGORITHM);
    }

    public static void main(String[] args) {
        String content = "hello,您好";
        String key = "4sde34&df8543*er";
        System.out.println("content:" + content);
        String s1 = AESUtil.encrypt(content, key);
        System.out.println("s1:" + s1);
        System.out.println("s2:"+AESUtil.decrypt(s1, key));

    }

}

RSA 加解密

public class RSAUtil {
    public static Map<Integer, String> keyMap = new HashMap<Integer, String>();  //用于封装随机产生的公钥与私钥

    /**
     * 随机生成密钥对
     *
     * @throws NoSuchAlgorithmException
     */
    public static void genKeyPair() throws NoSuchAlgorithmException {
        // 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，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();
        RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();   // 得到私钥
        RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();  // 得到公钥
        String publicKeyString = Base64.encodeToString(publicKey.getEncoded(), Base64.DEFAULT);
        // 得到私钥字符串
        String privateKeyString = Base64.encodeToString(privateKey.getEncoded(), Base64.DEFAULT);
        // 将公钥和私钥保存到Map
        keyMap.put(0, publicKeyString);  //0表示公钥
        keyMap.put(1, privateKeyString);  //1表示私钥
    }

    /**
     * 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 = Base64.decode(publicKey, Base64.DEFAULT);
        RSAPublicKey pubKey = (RSAPublicKey) KeyFactory.getInstance("RSA").generatePublic(new X509EncodedKeySpec(decoded));
        //RSA加密
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.ENCRYPT_MODE, pubKey);
        return Base64.encodeToString(cipher.doFinal(str.getBytes(StandardCharsets.UTF_8)), Base64.DEFAULT);
    }

    /**
     * RSA私钥解密
     *
     * @param str        加密字符串
     * @param privateKey 私钥
     * @return 铭文
     * @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 = Base64.decode(str.getBytes(StandardCharsets.UTF_8), Base64.DEFAULT);
        //base64编码的私钥
        byte[] decoded = Base64.decode(privateKey, Base64.DEFAULT);
        RSAPrivateKey priKey = (RSAPrivateKey) KeyFactory.getInstance("RSA").generatePrivate(new PKCS8EncodedKeySpec(decoded));
        //RSA解密
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.DECRYPT_MODE, priKey);
        return new String(cipher.doFinal(inputByte));
    }

}