Java中的RSA BadPaddingException - 在Android中的加密解密JRE

Question

我发现了一些其他问题，但我没有找到解释是什么原因造成的。我用Java编写了一个函数来加密数据，将其存储到一个文件中，并解密它再次加载文件。由于这是一个非对称加密，我有一个公钥和一个私钥，直接存储在代码中用于测试目的。

这个问题似乎是加密本身的差异，因为该功能在android以及安装了java RE 7的Windows机器上工作。但是在JRE7系统上使用相同的密钥和功能加密来自Android的数据是不可能的，结果是“bad padding exeption”。

对于测试目的，我只使用一个数据块。由于en/decrypt在每个系统中都有效，所以我相信问题不是关键。最终版本将编码和解码二进制数据 - 所以我只是使用字节，不必担心字符串中的不同字符集。在了解了原因之后，我将使用pureRSA解码PHP中的数据。

import java.io.DataInputStream; 
import java.io.FileInputStream; 
import java.io.DataOutputStream; 
import java.io.FileOutputStream; 
import android.util.Base64; 
import java.math.BigInteger; 
import java.security.InvalidAlgorithmParameterException; 
import javax.crypto.Cipher; 
import java.security.KeyFactory; 
import java.security.spec.RSAPublicKeySpec; 
import java.security.spec.PKCS8EncodedKeySpec; 
import java.security.interfaces.RSAPrivateKey; 
import java.security.interfaces.RSAPublicKey; 
import java.security.NoSuchAlgorithmException; 
import java.security.NoSuchProviderException; 
import java.security.spec.InvalidKeySpecException; 
import javax.crypto.NoSuchPaddingException; 
import java.security.InvalidKeyException; 
import javax.crypto.IllegalBlockSizeException; 
import javax.crypto.BadPaddingException; 
import javax.crypto.ShortBufferException; 
import java.io.FileNotFoundException; 
import java.io.UnsupportedEncodingException; 
import java.io.IOException; 

public class test 
{ 
    public static void main (String args[]) throws FileNotFoundException, FileNotFoundException, 
      UnsupportedEncodingException, IOException, NoSuchAlgorithmException, InvalidKeySpecException, 
      NoSuchPaddingException, InvalidKeyException, IllegalBlockSizeException, BadPaddingException, 
      ShortBufferException, NoSuchProviderException, InvalidAlgorithmParameterException { 

     Cipher CheckCipher = Cipher.getInstance("RSA"); 
     KeyFactory fact = KeyFactory.getInstance("RSA"); 
// one Block has 320 Bytes encrypted data or up to 309 Bytes decrypted data 
     byte[] encryptedBuffer = new byte[320]; 
// public key 
     RSAPublicKeySpec pubKeySpec = new RSAPublicKeySpec(new BigInteger("348349717397217997016459044429876445798461822630613593827475516398929980499253048018915109820386668925158598090923917424889721436728681941788735398708226655486687058044818981687475046995966049152458371358433593409946449307673641432434645409125209056679079565878576322466469782078766479519331465759437687570449909733209874455595086928288016285095448723528960074392901021635076277130066403766286870175583368291319265676733584876043054873738027872260931903992491855282040202055048433338277681906526276056353076551640420301024861314931536846223479281788109044598118149113100016473709709779349227018363507068247312704031804719673776595496482605126340630418742698424978233098157782472641000027452801691972881854034867234891280067908910242015420737297077922221753325197819914227"), new BigInteger("65537")); 
     RSAPublicKey publicKey = (RSAPublicKey) fact.generatePublic(pubKeySpec); 
// private key 
     byte[] encoded = Base64.decode("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", Base64.DEFAULT); 
     PKCS8EncodedKeySpec privateKeySpec = new PKCS8EncodedKeySpec(encoded); 
     RSAPrivateKey debugprivateKey = (RSAPrivateKey) fact.generatePrivate(privateKeySpec); 

// selftest (encrypt data) 
     String OutPutEncryption = "debug.exponent.javatest2.txt"; 
     CheckCipher.init(Cipher.ENCRYPT_MODE, publicKey); 
     DataOutputStream cryptFile = new DataOutputStream(new FileOutputStream(OutPutEncryption)); 
     byte[] decryptedBuffer = new byte[] {100, 110, 112, 99, 64}; // some data 5 bytes 
     CheckCipher.doFinal(decryptedBuffer, 0, 5, encryptedBuffer); 
     cryptFile.write(encryptedBuffer); 
     cryptFile.close(); 

// decrypt data from selftext or external source 
     String SourceFile = "debug.exponent.javatest2.txt"; 
     CheckCipher.init(Cipher.DECRYPT_MODE, debugprivateKey); 
     DataInputStream readCryptFileDeb = new DataInputStream(new FileInputStream(SourceFile)); 
     readCryptFileDeb.read(encryptedBuffer); 
     readCryptFileDeb.close(); 
     byte[] Test = CheckCipher.doFinal(encryptedBuffer); 
     System.out.println(new String(Test)); 
    } 
} 

Answer 1

不幸的是我目前还没有运行Android系统来测试它，但我猜想可能会选择不同的填充算法。

所以给它一个尝试，explicitley选择填充算法，像这样：

Cipher CheckCipher = Cipher.getInstance("RSA/ECB/PKCS1Padding"); 

请注意，您还可以选择在这种情况下，一个块链接模式。在这种情况下，我选择了“ECB”（=无块链接），因为我认为这是默认值。