关于RAS加密解密的一个文章,看着一个就够了!!!
程序员文章站
2024-03-14 14:12:46
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RAS在网上看了太多文章很多都是不全的,复制过去各种问题,所有就有写个博客的想法,一是方便大家,二是方便自己,好了废话不多说了!
首先要注意一下证书级别
1024位的证书,加密时最大支持117个字节,解密时为128;
2048位的证书,加密时最大支持245个字节,解密时为256。
创建RAS工具类
package club.loserblog.blogreception.util;
import org.apache.tomcat.util.http.fileupload.ByteArrayOutputStream;
import sun.misc.BASE64Decoder;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import java.io.IOException;
import java.security.*;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.Base64;
/**
* @ClassName RsaUtil
* @Description TODO
* @Author loser
* @Date 2020/4/12 18:26
**/
public class RsaUtil {
private PublicKey commonKey;
private PrivateKey secrecyKey;
/*
* 1024位的证书,加密时最大支持117个字节,解密时为128;
* 2048位的证书,加密时最大支持245个字节,解密时为256。
* */
/**
* @Author: dingmingming
* @Description: 初始化公钥和**
* @Date: 2020/4/12 18:37
* @Param:
* @Return:
**/
public RsaUtil() throws GeneralSecurityException{
KeyPairGenerator pairGenerator = KeyPairGenerator.getInstance("RSA");
pairGenerator.initialize(1024);
KeyPair keyPair = pairGenerator.generateKeyPair();
this.commonKey = keyPair.getPublic();
this.secrecyKey = keyPair.getPrivate();
}
/**
* @Author: dingmingming
* @Description: 恢复公钥和**
* @Date: 2020/4/12 18:37
* @Param:
* @Return:
**/
public RsaUtil(byte[] commonKey,byte[] secrecyKey) throws GeneralSecurityException{
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(commonKey);
this.commonKey = keyFactory.generatePublic(x509EncodedKeySpec);
PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(secrecyKey);
this.secrecyKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
}
/**
* @Author: dingmingming
* @Description: 将公钥转换为字节
* @Date: 2020/4/12 18:39
* @Param:
* @Return:
**/
public byte[] getCommonKey(){
return commonKey.getEncoded();
}
/**
* @Author: dingmingming
* @Description: 将私钥转换为字节
* @Date: 2020/4/12 18:39
* @Param:
* @Return:
**/
public byte[] getSecrecyKey(){
return secrecyKey.getEncoded();
}
/**
* @Author: dingmingming
* @Description: 利用公钥加密
* @Date: 2020/4/12 18:45
* @Param:
* @Return:
**/
public String encryptStr(String encryptStr) throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException, IOException {
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(1, this.commonKey);
byte[] result = encryptStr.getBytes();
int inputLen = result.length;
ByteArrayOutputStream out = new ByteArrayOutputStream();
int offSet = 0;
for(int i = 0; inputLen - offSet > 0; offSet = i * 117) {
byte[] cache;
if(inputLen - offSet > 117) {
cache = cipher.doFinal(result, offSet, 117);
} else {
cache = cipher.doFinal(result, offSet, inputLen - offSet);
}
out.write(cache, 0, cache.length);
++i;
}
byte[] encryptedData = out.toByteArray();
out.close();
String encryptData = Base64.getEncoder().encodeToString(encryptedData);
return encryptData;
}
/**
* @Author: dingmingming
* @Description: 利用私钥解密
* @Date: 2020/4/12 18:45
* @Param:
* @Return:
**/
public String decryptStr(String decryptStr) throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException, IOException {
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(2, secrecyKey);
byte[] result = new BASE64Decoder().decodeBuffer(decryptStr);
int inputLen = result.length;
ByteArrayOutputStream out = new ByteArrayOutputStream();
int offSet = 0;
for(int i = 0; inputLen - offSet > 0; offSet = i * 128) {
byte[] cache;
if(inputLen - offSet > 128) {
cache = cipher.doFinal(result, offSet, 128);
} else {
cache = cipher.doFinal(result, offSet, inputLen - offSet);
}
out.write(cache, 0, cache.length);
++i;
}
byte[] decryptedData = out.toByteArray();
out.close();
String decryptData = new String(decryptedData,"UTF-8");
return decryptData;
}
}
获取前端数据处理
public ModelAndView getBlogInfoForLook(HttpServletRequest request) throws IllegalBlockSizeException, InvalidKeyException, BadPaddingException, NoSuchAlgorithmException, NoSuchPaddingException, IOException {
//blogId 代表的是前端的参数名称 这个大家应该都了解
String blogId = request.getParameter("blogId").trim();
//这里是重点要注意的 一定要替换
//为什么要替换 因为参数传递的过程中 会将加密字符中的加号变成空格,因此我们需要将其替换回来 避免解密失败
blogId = blogId.replaceAll(" ","+");
//可以进行揭秘操作了
}
前端这一块我只是重点说一下解密 ,因为解密猜的坑有点多,加密都没有什么问题调用方法就行
好了就这样了!!!
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