AESUtil

package com.xxx.common.utils;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.security.SecureRandom;
import java.util.Base64;


/**
* @Author Michael
**/
public class AESUtil {
/**
* 加密算法
*/
private static final String ALGORITHM = "AES";
/**
* 秘钥长度
*/
private static final Integer KEY_LENGTH = 128;
/**
* 默认编码
*/
private static final String CHARSET = "utf-8";
/**
* 秘钥
*/
private static final String KEY = "8DEA499312A2BFC2";

private static final String PKCS5PADDINGALGORITHM = "AES/CBC/PKCS5Padding";


public static void main(String[] args) throws Exception {
String content = "你好啊啊啊啊啊啊阿瓦啊啊啊啊所所所所所所多多多多多多多多多多";

String encrypt = youliaoEncrypt(content);
System.out.println(encrypt);


String decrypt = youliaoDecrypt(encrypt);
System.out.println(decrypt);
}
public static boolean isChecked(String key) {
return KEY.equals(key);
}
public static String youliaoEncrypt(String content) {
return encryptToAESPKCS5(content);
}


/**
* encryptToAESPKCS5:加密AES
*
* @param content : 加密内容
* @return
*/
public static String encryptToAESPKCS5(String content) {
byte[] encryptResult = null;
try {
// 密钥
SecretKeySpec secretKey = new SecretKeySpec(KEY.getBytes(), "AES");
// 算法/模式/填充
Cipher cipher = Cipher.getInstance(PKCS5PADDINGALGORITHM);
byte[] byteContent = content.getBytes("utf-8");
// 初始化向量,在密钥相同的前提下,加上初始化向量,相同内容加密后相同
IvParameterSpec zeroIv = new IvParameterSpec(KEY.getBytes());
cipher.init(Cipher.ENCRYPT_MODE, secretKey, zeroIv);
encryptResult = cipher.doFinal(byteContent);

}
catch(Exception e) {
// TODO: handle exception
e.printStackTrace();
}
return Base64.getEncoder().encodeToString(encryptResult);
}

/**
* decryptToAESPKCS5:解密AES
*
* @param content : 解密内容
* @return
*/
public static String decryptToAESPKCS5(String content) {
byte[] decryptResult = null;
try {
// 密钥
SecretKeySpec secretKey = new SecretKeySpec(KEY.getBytes(), "AES");
Cipher cipher = Cipher.getInstance(PKCS5PADDINGALGORITHM);
// base64转换
byte[] byteContent = Base64.getDecoder().decode(content);
IvParameterSpec zeroIv = new IvParameterSpec(KEY.getBytes());
cipher.init(Cipher.DECRYPT_MODE, secretKey, zeroIv);
decryptResult = cipher.doFinal(byteContent);

return new String(decryptResult, "utf-8");
}
catch(Exception e) {
// TODO: handle exception
e.printStackTrace();
}
return null;
}
/** 生成key
*
* @param password
* @return
* @throws Exception
*/
private static SecretKeySpec generateKey(String password) throws Exception {

SecureRandom random = SecureRandom.getInstance("SHA1PRNG");//修改后
random.setSeed(KEY.getBytes());

// 创建AES的Key生产者
KeyGenerator kgen = KeyGenerator.getInstance(ALGORITHM);
// 利用用户密码作为随机数初始化出
// SecureRandom是生成安全随机数序列,password.getBytes()是种子,只要种子相同,序列就一样,所以解密只要有password就行
kgen.init(KEY_LENGTH, random);

// 根据用户密码,生成一个密钥
SecretKey secretKey = kgen.generateKey();

// 返回基本编码格式的密钥,如果此密钥不支持编码,则返回
byte[] enCodeFormat = secretKey.getEncoded();
// 转换为AES专用密钥
SecretKeySpec key = new SecretKeySpec(enCodeFormat, ALGORITHM);

// KeyGenerator kgen = KeyGenerator.getInstance("AES");
// kgen.init(128, new SecureRandom(key.getBytes()));//该行在linux下出现问题
// SecretKey secretKey = kgen.generateKey();
// byte[] enCodeFormat = secretKey.getEncoded();
// key2 = new SecretKeySpec(enCodeFormat, "AES");

// KeyGenerator kgen = KeyGenerator.getInstance("AES");

// kgen.init(128, random);

// SecretKey secretKey = kgen.generateKey();

// byte[] enCodeFormat = secretKey.getEncoded();
// key2 = new SecretKeySpec(enCodeFormat, "AES");
return key;
}

/**
* AES加密字符串
*
* @param content 需要被加密的字符串
* @param password 加密需要的密码
* @return 密文
*/
public static String encrypt(String content, String password) {
try {
SecretKeySpec key = generateKey(password);
// 创建密码器
Cipher cipher = Cipher.getInstance(ALGORITHM);
byte[] byteContent = content.getBytes(CHARSET);
// 初始化为加密模式的密码器
cipher.init(Cipher.ENCRYPT_MODE, key);
// 加密
byte[] result = cipher.doFinal(byteContent);
// 二进制转换成16进制字符串
String hexStr = parseByte2HexStr(result);

return hexStr;
} catch (Exception e) {
e.printStackTrace();
}
return null;
}

/**
* 解密AES加密过的字符串
*
* @param content AES加密过过的内容
* @param password 加密时的密码
* @return 明文
*/
public static String decrypt(String content, String password) {
try {
// 十六进制字符串转换成二进制字节数组
byte[] byteArr = parseHexStr2Byte(content);

SecretKeySpec key = generateKey(password);
Cipher cipher = Cipher.getInstance(ALGORITHM);
cipher.init(Cipher.DECRYPT_MODE, key);
// 解密
byte[] result = cipher.doFinal(byteArr);

return new String(result,CHARSET);
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
public static String youliaoDecrypt(String content) {
return decryptToAESPKCS5(content);
}

/**将二进制转换成16进制
* @param buf
* @return
*/
public 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();
}

/**将16进制转换为二进制
* @param hexStr
* @return
*/
public 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);
int low = Integer.parseInt(hexStr.substring(i*2+1, i*2+2), 16);
result[i] = (byte) (high * 16 + low);
}
return result;
}
}
原文地址:https://www.cnblogs.com/michaelcnblogs/p/15735947.html