AES對稱加密

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

/**
 * Created by 黃俊聰 on 2017/12/15.
 */
public class AESUtil {

    public static final String KEY_ALGORITHM = "AES";
    public static final String KEY_ALGORITHM_MODE = "AES/CBC/PKCS5Padding";

    /**
     *@Author 黃俊聰
     *@Date 2017/12/15 15:44
     *@Description AES對稱加密
     * @param data
     * @param key key需要16位
     */

    public static String encrypt(String data,String key){
        try {
            SecretKeySpec spec = new SecretKeySpec(key.getBytes("UTF-8"),KEY_ALGORITHM);
            Cipher cipher = Cipher.getInstance(KEY_ALGORITHM_MODE);
            cipher.init(Cipher.ENCRYPT_MODE , spec,new IvParameterSpec(new byte[cipher.getBlockSize()]));
            byte[] bs = cipher.doFinal(data.getBytes("UTF-8"));
            return Base64Util.encode(bs);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return  null;
    }


    /**
     *@Author 黃俊聰
     *@Date 2017/12/15 15:50
     *@Description
     * AES對稱解密 key需要16位
     * @param data
     * @param key
     * @return
     */
    public static String decrypt(String data, String key) {
        try {
            SecretKeySpec spec = new SecretKeySpec(key.getBytes("UTF-8"), KEY_ALGORITHM);
            Cipher cipher = Cipher.getInstance(KEY_ALGORITHM_MODE);
            cipher.init(Cipher.DECRYPT_MODE , spec , new IvParameterSpec(new byte[cipher.getBlockSize()]));
            byte[] originBytes = Base64Util.decode(data);
            byte[] result = cipher.doFinal(originBytes);
            return new String(result,"UTF-8");
        } catch (Exception e) {
            e.printStackTrace();
        }
        return  null;
    }


    public static void main(String[] args) throws Exception {
        /**AES加密數據**/
        String key = "123456789abcdfgt";
        String dataToEn = "黃俊聰";
        String enResult = encrypt(dataToEn, key);
        System.out.println(enResult);
//        String deResult = decrypt(enResult,key);
//        System.out.println(deResult);

        /**RSA 加密AES的密鑰**/
        byte[] enKey = RSAUtil.encryptByPublicKey(key.getBytes("UTF-8"), "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCbpmF28RgRDMduGSDhB2CD 0CiOFYytTGxYQuffq5RTgdoxxsE/3dgE+qQaDsTG1yzOwwCq7X3Xye7MZlcL 5SjNiLzh5tSEG7qyAVUfAgit1gYczWM+sTg+G7pnHa/omukvOfEeWceS8P35 Xt3ShqIeKfGxU4UIdiqKonBrQtYT/wIDAQAB");
        System.out.println(new String(enKey,"UTF-8"));
        String baseKey = Base64Util.encode(enKey);

        //服務端RSA解密AES的key
        byte[] de = Base64Util.decode(baseKey);
        byte[] deKeyResult = RSAUtil.decryptByPrivateKey(de);
        System.out.println(new String(deKeyResult,"UTF-8"));

        String deResult = decrypt(enResult,key);
        System.out.println(deResult);
    }

//Base64工具類
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;

public class Base64Util {
    private static final char[] legalChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
            .toCharArray();



    public static String encode(byte[] data) {
        byte start = 0;
        int len = data.length;
        StringBuffer buf = new StringBuffer(data.length * 3 / 2);
        int end = len - 3;
        int i = start;
        int n = 0;

        int d;
        while (i <= end) {
            d = (data[i] & 255) << 16 | (data[i + 1] & 255) << 8 | data[i + 2] & 255;
            buf.append(legalChars[d >> 18 & 63]);
            buf.append(legalChars[d >> 12 & 63]);
            buf.append(legalChars[d >> 6 & 63]);
            buf.append(legalChars[d & 63]);
            i += 3;
            if (n++ >= 14) {
                n = 0;
                buf.append(" ");
            }
        }

        if (i == start + len - 2) {
            d = (data[i] & 255) << 16 | (data[i + 1] & 255) << 8;
            buf.append(legalChars[d >> 18 & 63]);
            buf.append(legalChars[d >> 12 & 63]);
            buf.append(legalChars[d >> 6 & 63]);
            buf.append("=");
        } else if (i == start + len - 1) {
            d = (data[i] & 255) << 16;
            buf.append(legalChars[d >> 18 & 63]);
            buf.append(legalChars[d >> 12 & 63]);
            buf.append("==");
        }

        return buf.toString();
    }

    private static int decode(char c) {
        if (c >= 65 && c <= 90) {
            return c - 65;
        } else if (c >= 97 && c <= 122) {
            return c - 97 + 26;
        } else if (c >= 48 && c <= 57) {
            return c - 48 + 26 + 26;
        } else {
            switch (c) {
            case '+':
                return 62;
            case '/':
                return 63;
            case '=':
                return 0;
            default:
                throw new RuntimeException("unexpected code: " + c);
            }
        }
    }

    public static byte[] decode(String s) {
        ByteArrayOutputStream bos = new ByteArrayOutputStream();

        try {
            decode(s, bos);
        } catch (IOException var5) {
            throw new RuntimeException();
        }

        byte[] decodedBytes = bos.toByteArray();

        try {
            bos.close();
            bos = null;
        } catch (IOException var4) {
            System.err.println("Error while decoding BASE64: " + var4.toString());
        }

        return decodedBytes;
    }

    private static void decode(String s, OutputStream os) throws IOException {
        int i = 0;
        int len = s.length();

        while (true) {
            while (i < len && s.charAt(i) <= 32) {
                ++i;
            }

            if (i == len) {
                break;
            }

            int tri = (decode(s.charAt(i)) << 18) + (decode(s.charAt(i + 1)) << 12) + (decode(s.charAt(i + 2)) << 6)
                    + decode(s.charAt(i + 3));
            os.write(tri >> 16 & 255);
            if (s.charAt(i + 2) == 61) {
                break;
            }

            os.write(tri >> 8 & 255);
            if (s.charAt(i + 3) == 61) {
                break;
            }

            os.write(tri & 255);
            i += 4;
        }

    }

}

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