AES

AES

问题：

• 密钥为十六进制的字符串
• 密文为十六进制的字符串

AES操作过程

1. 加密

   //1.将明文转化为字节数组
    byte[] data = message.getBytes("UTF-8");
   // 2.将密钥也转为字节数组
   byte[] key=...
   // 3. 加密 encrypted
   // 3.1 创建cipher （译为密码
        Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");// 模式，填充
   // 3.2 创建 SecretKey 密钥
   SecretKey keySpec = new SecretKeySpec(key, "AES");
   // 3.3 用密钥进行初始化
   cipher.init(Cipher.ENCRYPT_MODE, keySpec);
   // 3.4 加密 返回byte[]
   cipher.doFinal(data);
   

2. 解密

   //key 和 data都是二进制字节数组
   Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
           SecretKey keySpec = new SecretKeySpec(key, "AES");
           cipher.init(Cipher.DECRYPT_MODE, keySpec);
    cipher.doFinal(input);
   

3. 完整代码：

   import javax.crypto.Cipher;
   import javax.crypto.spec.SecretKeySpec;
   import java.io.UnsupportedEncodingException;
   
   
   public class AESTest2 {
   
       /**
        * 加密
        *
        * @param content
        *            需要加密的内容
        * @param password
        *            加密密码
        * @return
        */
       private static byte[] encryptData_AES(String content, String password) {
           try {
   
               byte[] enCodeFormat = parseHexStr2Byte(password);
   
               SecretKeySpec key = new SecretKeySpec(enCodeFormat, "AES");
               Cipher cipher = Cipher.getInstance("AES");// 创建密码器
               byte[] byteContent = content.getBytes("UTF-8");
               cipher.init(Cipher.ENCRYPT_MODE, key);// 初始化
               byte[] result = cipher.doFinal(byteContent);
               return result; // 加密
           } catch (Exception e) {
               e.printStackTrace();
           }
           return null;
       }
   
   
       /**
        * 将16进制转换为二进制
        *
        * @param hexStr
        * @return
        */
   
       private static byte[] parseHexStr2Byte(String hexStr) {
           if (hexStr.length() < 1)
               return null;
           byte[] result = new byte[hexStr.length() / 2];
           for (int i = 0; i < hexStr.length() / 2; i++) {
               int high = Integer.parseInt(hexStr.substring(i * 2, i * 2 + 1), 16); //将radix进制的字符串转化为十进制
               int low = Integer.parseInt(hexStr.substring(i * 2 + 1, i * 2 + 2),
                       16);
               result[i] = (byte) (high * 16 + low);//转化为十进制 然后在强转为二进制
           }
           return result;
       }
   
       /**
        * 将二进制转换成16进制
        *
        * @param buf
        * @return
        */
       private static String parseByte2HexStr(byte buf[]) {
           StringBuffer sb = new StringBuffer();
           for (int i = 0; i < buf.length; i++) {
   
               String hex = Integer.toHexString(buf[i] & 0xFF);
               if (hex.length() == 1) {
                   hex = '0' + hex;
               }
               sb.append(hex.toUpperCase());
           }
           return sb.toString();
       }
       /**
        * 字符串加密
        *
        * @param srcStr
        *            加密字符串
        * @param password
        *            加密密钥
        * */
       public static String encryptStr(String srcStr, String password) {
   
           byte[] encryptResult = encryptData_AES(srcStr, password);
           String encryptResultStr = parseByte2HexStr(encryptResult);
           return encryptResultStr;
       }
       /**
        * 解密
        *
        * @param encrystr
        *            密文
        * @param password
        *            密钥
        * @return 解密后的字符串
        */
       public static  String decryptStr(String encryptStr,String password)  {
           byte[] decryptResult=decryptData_AES(encryptStr,password);
           try {
               String  decryptStr= new String(decryptResult,"UTF-8");
               return  decryptStr;
           }
           catch (Exception e){
               e.printStackTrace();
           }
           return null;
       }
   
       /**
        * 解密
        *
        * @param encrystr
        *            密文
        * @param password
        *            密钥
        * @return 解密后的二进制数据
        */
       public static byte[] decryptData_AES(String encryptStr,String password){
           try {
   
               byte[] deCodeFormat = parseHexStr2Byte(password);
               byte[] byteContent = parseHexStr2Byte(encryptStr);
               SecretKeySpec key = new SecretKeySpec(deCodeFormat, "AES");
               Cipher cipher = Cipher.getInstance("AES");// 创建密码器
               cipher.init(Cipher.DECRYPT_MODE, key);// 初始化
               byte[] result = cipher.doFinal(byteContent);
               return result; // 解密
           } catch (Exception e) {
               e.printStackTrace();
           }
           return null;
       }
   
       public static void main(String[] args) throws UnsupportedEncodingException {
           String encryptMessage=encryptStr("2015021115122300", "ADED51171767497B94368AF51050754D");
           System.out.println(encryptMessage);
           String message=decryptStr(encryptMessage,"ADED51171767497B94368AF51050754D");
           System.out.println(message);
       }
   
   }