RSA对称加密 Util工具类

证书Key直接去换行符存放到就可以更方便,如果需要做安全的话可以把字段放到so层比较好

public class RSAUtil {
    public static final String KEY_ALGORITHM = "RSA";
    public static final String SIGNATURE_ALGORITHM = "MD5withRSA";
    private static final int KEY_SIZE = 1024;
    private static final String PUBLIC_KEY = "RSAPublicKey";
    private static final String PRIVATE_KEY = "RSAPrivateKey";
    public static String str_pubK = "MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAs6lJ8f52yfY4FlQDkpBBHcIdd2GH+fdjvQaI28Hmhzvz+6vc/cfkoc7Gk7n55aXnpu28/2HNk3i8Yw8HXR7hwkqFn5Yw8X9qmui11dk2RYO86WLYIzP8sqQuMpZQkF/qnAxAzbWCNA0sXCIjF4qBm3tw06CmJ2X2rr21WoAcBy6zCLuyU/VJOfVWaUMlnIvZqGZRXmSU6JBS5nnk06o4YG91ZWasWZzKQ9lNycsL7KUbxQeO6OElZaFY3FmVQP8bmvtmVL66bH5h6T4Rj5+Tz1EMea3Dl3o7QMXdIX2WBVQo5nte1jKzC4rWfBqcgzFN3kcSQVMfj+uucAK82uwmEQIDAQAB";
    public static String str_priK = "MIIEvgIBADANBgkqhkiG9w0BAQEFAASCBKgwggSkAgEAAoIBAQCoYmgZgevtZmYrvX9F3rHqSrfpDr+/Gh72zBcAQaTNi/driNQ9fAeyjgs4H2TDDWHpJi2/6Itm21kBCe8p6ylKrAWJMcM+fD476dDqQrm/GHYoUtAWGhBiErC++NOGgDHpwFcDh8uQkHVH6+CJjoRI8xbD15Uba4RMbdRQsMyDHmTi3Zpvj8WKJBZ5Gp/rJHYGQCQlR7pinQdXLvhSlsROgJAUq6KK9NbS/Y7fP5ImwkXi/U5qkMaWWU9XlL3MhX+YRKgCK2B92R1XBKL99UlixHigBtLMIuFdvzyPfhZ66pq8byuqk7jyR2VSEzsTG3PjPnhJVf/Zyuyp/XWJrFBHAgMBAAECggEAIOB16uUPJ58iu8+YFhBRNKm6FusmTS3QdeeLZiVrBCcb/AcPSaH57scFMcQPbHYkc91ceWfyL/cL/cPuyoR733SO8CajNIQVsqUIgXTdx44DJARnVKlqIXv8voze4BgPptBDLRFKkcNi4tQPV0xYT9YGz9474sqvXizjk42xoLfxNWdLI6Q6jkmg+367oIgDI4askbQMII5+/UrGtXKSZaaKrQA7jWSunE+kFCBzb2IWkDW1kyK3HXQFdNeGwQj6SO5MSqi7l0UQFU3TSxWzuWlG34mnGSX6hF5J+25MD0tTs2lIKO6MKiz1V1OSqL7ca/TLTVTjlGW2TUZsvCF/YQKBgQDftBhz74lXaTTJtBAIlfURSeVAe6+jg/y6xtEo/mY+r7X01/yrSykA+6AFmG8ICSbk/fn4pynwJTF/3raFDRgB0DpxxjUEsLWyfo1O3FlJPIGNZN5JfzzeetPyBtdvfEc9oVrMZjUez3gjrTwoebJklxPUghMo+ot8r4AQyN3kewKBgQDAscLRnWgtQg+5gE461qw9Nm/anLKe+ucM3kaFyApF6nnvRb+FGdwUj54wSyAX19/rxaNE8O4da7sohc/8PNUOqyOipiKRQgqz3G3frTusnv/Frt0uGIpjq3IWFT/Uk7yr9KXdvgiNozot87n73aQsxThWwHSEQrFrRvqsKhMXpQKBgQCY82EYu7mS22rtUkD4Ldeel4C4oxjG2zKMXe2acr5js+3b12V5lO0XL/QMf1nDC8bdIM2t9lWVTUjX3eW7eOVmMAIV0mhjqZLB1Qc22S/vBACsNUBKzkVG9II/Y/Ae2ME44T7crDE7vKyu7/5GylZvsmArlzgUd6Gxgak1ULFuSwKBgF9OzPxeratM9Hgc5RSnH3P7W+G2BYcqtGMiAaGj6qjgK8VUK0FLJBarXmOmlM4WQTPdgj7UKAI3Sc/mN5QcBomFzk9hetF7581EZrfueAiOcBW3wsBM9Q4NO5V+lx6un/AxRmTh3Fsp89nMph3UZ6KZPZ9y+257ikN0TQIgoWbdAoGBALQtafyZZjPGuYHoNd/mO8+s2WTe48T+HxvBSqK6SvkuMUqhNbTcUym1c8H6WTUKR7hbfwuGsqRjJVhWTw5O66zN4T9LAdewhHcbXmZE/BNmHvDVqUoJ4C4yiZzzIMXHaMdM40D+WgBVay8N6fd1XK4rst92fYR86bE5kCGPXXQ9";

    /**
     * 得到公钥
     *
     * @param key 密钥字符串（经过base64编码）
     * @throws Exception
     */
    public static PublicKey getPublicKey(String key) throws Exception {
        byte[] keyBytes;
        keyBytes = (new BASE64Decoder()).decodeBuffer(key);
        X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PublicKey publicKey = keyFactory.generatePublic(keySpec);
        return publicKey;
    }

    /**
     * 得到私钥
     *
     * @param key 密钥字符串（经过base64编码）
     * @throws Exception
     */
    public static PrivateKey getPrivateKey(String key) throws Exception {
        byte[] keyBytes;
        keyBytes = (new BASE64Decoder()).decodeBuffer(key);
        PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PrivateKey privateKey = keyFactory.generatePrivate(keySpec);
        return privateKey;
    }

    //***************************签名和验证*******************************
    public static byte[] sign(byte[] data) throws Exception {
        PrivateKey priK = getPrivateKey(str_priK);
        Signature sig = Signature.getInstance(SIGNATURE_ALGORITHM);
        sig.initSign(priK);
        sig.update(data);
        return sig.sign();
    }

    public static boolean verify(byte[] data, byte[] sign) throws Exception {
        PublicKey pubK = getPublicKey(str_pubK);
        Signature sig = Signature.getInstance(SIGNATURE_ALGORITHM);
        sig.initVerify(pubK);
        sig.update(data);
        return sig.verify(sign);
    }

    //************************加密解密**************************
    public static byte[] encrypt(byte[] bt_plaintext) throws Exception {
        PublicKey publicKey = getPublicKey(str_pubK);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.ENCRYPT_MODE, publicKey);
        byte[] bt_encrypted = cipher.doFinal(bt_plaintext);
        return bt_encrypted;
    }

    public static byte[] decrypt(byte[] bt_encrypted) throws Exception {
        PrivateKey privateKey = getPrivateKey(str_priK);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.DECRYPT_MODE, privateKey);
//        byte[] result;
//        byte[] inputArray = bt_encrypted;
//        int inputLength = inputArray.length;
//        System.out.println("加密字节数：" + inputLength);
//        int MAX_ENCRYPT_BLOCK = 256;
//        // 标识
//        int offSet = 0;
//        byte[] resultBytes = {};
//        byte[] cache = {};
//        while (inputLength - offSet > 0) {
//            if (inputLength - offSet > MAX_ENCRYPT_BLOCK) {
//                cache = cipher.doFinal(inputArray, offSet, MAX_ENCRYPT_BLOCK);
//                offSet += MAX_ENCRYPT_BLOCK;
//            } else {
//                cache = cipher.doFinal(inputArray, offSet, inputLength - offSet);
//                offSet = inputLength;
//            }
//            resultBytes = Arrays.copyOf(resultBytes, resultBytes.length + cache.length);
//            System.arraycopy(cache, 0, resultBytes, resultBytes.length - cache.length, cache.length);
//        }
//        result = Base64.encodeBase64(resultBytes);
        byte[] bt_original = cipher.doFinal(bt_encrypted);
        return bt_original;
    }

    //********************main函数：加密解密和签名验证*********************
    public static void main(String[] args) throws Exception {
//        String str_plaintext = "这是一段用来测试密钥转换的明文";
//        System.err.println("明文：" + str_plaintext);
//        byte[] bt_cipher = encrypt(str_plaintext.getBytes());
//        System.out.println("加密后：" + Base64.encodeBase64String(bt_cipher));
//
//
        byte[] bt_original = decrypt(Base64.decodeBase64("eaOm2Vf2syg5Kc+OkEXnbRKW1MWdJnkCX5tjlAygDNIpQm1LfFK57OQ/fNK3lSBs7DSVm8SFkhrsOwb/zhW749xo+IzZ9VrCiiYtPfo4zEb9BrlXUXxgee943gOXHTukapATvxKUTWtjEJOw/WABP0t1KON4yWZVntPpvbwh1VTO5WIWvbF8r/jBHORfNqqHaPsG+j/G7z/4RQ9Xnvaak/3BHSA55aYC0r9c8YzYLWxhm0aiSyp+DGY77d80LdpGtqfv1J4e3g+joBeuJLn+qbAsu86uv63XaOZBI2OwBcJksKUPTcvcdppTQZvDGQmOmNrddqOdqBVUYqF582uRfA=="));
        String str_original = new String(bt_original);
        System.out.println("解密结果:" + str_original);
//
//        String str = "被签名的内容";
//        System.err.println("\n原文:" + str);
//        byte[] signature = sign(str.getBytes());
//        System.out.println("产生签名：" + Base64.encodeBase64String(signature));
//        boolean status = verify(str.getBytes(), signature);
//        System.out.println("验证情况：" + status);
    }

}