使用 AES 公钥加密的代理重新加密

问题描述

我用 Alice 公钥加密纯文本，但我想用 Bob 私钥而不是 Alice 私钥解密这个 Alice 密文。为此，我使用了代理重新加密技术。

proxy_key = (Bob_public_key)*(Alice_public_key.modInverse(prime_number)).mod(prime_number)

      public static void main(String[] args) throws UnsupportedEncodingException {  
      char ch[]=new char[16];
      String s = new String();
      BigInteger phi1=new BigInteger("31");

     //Alice private key= "pri1" and public key ="pub1"
      String pri1 = "0000000000000007"; // 128 bit key
      String pub1 = "0000000000000011";  
  
     //Encryption with Alice private and public key
      String Cipher=encrypt(pri1,pub1,"Hellow World");
      System.out.println("encrypted text = "+Cipher); 

      // CONVERT Alice public key "pub1" from String to BigInteger data type
      BigInteger pk1= new BigInteger(pub1) ;   

      //Bob private key= "pri2" and public key ="pub2" 
      String pri2 = "0000000000000013"; // 128 bit key
      String pub2 = "0000000000000017";     

      // CONVERT Bob public key "pub2" from String to BigInteger data type
      BigInteger pk2= new BigInteger(pub2) ;
      
      //Create ProxyKey  (proxy_key = bobs_public_key *(Alice_public_key.modInverse(random_value).mod(ranom_value) 
      BigInteger proxy_key = pk2.multiply(pk1.modInverse(phi1)).mod(phi1); 
 
      //The blow code convert proxy_key which value is "1" to "0000000000000001" 128 bit key
      s= String.valueOf(proxy_key);
      byte[] bytes = s.getBytes("US-ASCII");
      byte[] bytes1 =new byte[16];           
        for (int a=0;a<16;a++) {
                  if (a==15)
                     bytes1[a]=bytes[0];
                  else
                         bytes1[a]='0';
                     ch[a]= (char) (bytes1[a]);
                                     }
       String Proxy_re_encryption_key = String.copyValueOf(ch);
       System.out.println("the value of Proxy Re Encryption key ="+Proxy_re_encryption_key);
             
       //Encryption of Cipher with Proxy Re Encryption key
       String Cipher2=encrypt(pri1,Proxy_re_encryption_key,Cipher);
       System.out.println("2nd encrypted text = "+Cipher2); 
   
       //Decryption the 2nd cipher text with bobs public and private key
       System.out.println("Real Text = "+decrypt(pri2,pub2,Cipher2));
}

但是我出错了

javax.crypto.BadPaddingException: Given final block not properly padded. Such issues can 
arise if a bad key is used during decryption.
at java.base/com.sun.crypto.provider.CipherCore.unpad(CipherCore.java:977)
at java.base/com.sun.crypto.provider.CipherCore.fillOutputBuffer(CipherCore.java:1058)
at java.base/com.sun.crypto.provider.CipherCore.doFinal(CipherCore.java:855)
at java.base/com.sun.crypto.provider.AESCipher.engineDoFinal(AESCipher.java:446)
at java.base/javax.crypto.Cipher.doFinal(Cipher.java:2207)
at org.algorithm.work.junaid.EncryptionExample.decrypt(EncryptionExample.java:38)
at org.algorithm.work.junaid.EncryptionExample.main(EncryptionExample.java:95)   

加解密码

package org.algorithm.work.junaid;
import java.io.UnsupportedEncodingException;
import java.math.BigInteger;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import org.apache.commons.codec.binary.Base64;
public class EncryptionExample {
public static String encrypt(String key1,String key2,String value) {
    try {
        IvParameterSpec iv = new IvParameterSpec(key2.getBytes("UTF8"));

        SecretKeySpec skeySpec = new SecretKeySpec(key1.getBytes("UTF-8"),"AES");
        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
        cipher.init(Cipher.ENCRYPT_MODE,skeySpec,iv);
        byte[] encrypted = cipher.doFinal(value.getBytes());
        System.out.println("encrypted string:"
                + Base64.encodeBase64String(encrypted));
        return Base64.encodeBase64String(encrypted);
    } catch (Exception ex) {
        ex.printstacktrace();
    }
    return null;
}

public static String decrypt(String key1,String encrypted) {
    try {
        IvParameterSpec iv = new IvParameterSpec(key2.getBytes("UTF-8"));

        SecretKeySpec skeySpec = new SecretKeySpec(key1.getBytes("UTF-8"),"AES");
        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
        cipher.init(Cipher.DECRYPT_MODE,iv);
        byte[] original = cipher.doFinal(Base64.decodeBase64(encrypted));

        return new String(original);
    } catch (Exception ex) {
        ex.printstacktrace();
    }
    return null;
}

解决方法

暂无找到可以解决该程序问题的有效方法，小编努力寻找整理中！

如果你已经找到好的解决方法，欢迎将解决方案带上本链接一起发送给小编。

小编邮箱:dio#foxmail.com (将#修改为@）