GPG解密器無法正常工作

Question

我想寫gpg加密器/解密器（下面的代碼）。在第一步中，程序將加密「＃data1 \ n＃data2 \ n＃data3 \ n」字符串，並在下一步中解密解密返回的字節數組。但是......爲什麼來自解密器的文本與「＃data1 \ n＃data2 \ n＃data3 \ n」不一樣？我在哪裏錯過了什麼？謝謝你的幫助。

package tests.crypto; 

import java.io.File; 
import java.io.FileInputStream; 
import java.io.IOException; 
import java.io.InputStream; 
import java.security.InvalidKeyException; 
import java.security.NoSuchAlgorithmException; 
import java.security.NoSuchProviderException; 
import java.security.PrivateKey; 
import java.security.PublicKey; 
import java.security.Security; 
import java.util.Iterator; 

import javax.crypto.BadPaddingException; 
import javax.crypto.Cipher; 
import javax.crypto.IllegalBlockSizeException; 
import javax.crypto.NoSuchPaddingException; 

import org.bouncycastle.jce.provider.BouncyCastleProvider; 
import org.bouncycastle.openpgp.PGPException; 
import org.bouncycastle.openpgp.PGPPrivateKey; 
import org.bouncycastle.openpgp.PGPPublicKey; 
import org.bouncycastle.openpgp.PGPPublicKeyRing; 
import org.bouncycastle.openpgp.PGPPublicKeyRingCollection; 
import org.bouncycastle.openpgp.PGPSecretKey; 
import org.bouncycastle.openpgp.PGPSecretKeyRing; 
import org.bouncycastle.openpgp.PGPSecretKeyRingCollection; 
import org.bouncycastle.openpgp.PGPUtil; 
import org.bouncycastle.openpgp.operator.bc.BcPBESecretKeyDecryptorBuilder; 
import org.bouncycastle.openpgp.operator.bc.BcPGPDigestCalculatorProvider; 
import org.bouncycastle.openpgp.operator.jcajce.JcaPGPKeyConverter; 

import Decoder.BASE64Encoder; 

public class GPGTest { 

    char[] pass = { 'p', 'a', 's', 's' }; 

    public static void main(String[] args) throws Exception { 

     GPGTest gTest = new GPGTest(); 
     gTest.setUpCipher(); 
    } 

    public void setUpCipher() throws NoSuchAlgorithmException, 
      InvalidKeyException, IllegalBlockSizeException, 
      NoSuchProviderException, BadPaddingException, 
      NoSuchPaddingException { 

     System.out.println("--- setup cipher ---"); 

     // public key 
     String publicKeyFilePath = "E:/Programs/Keys/GPG/Public/public.key"; 
     File publicKeyFile = new File(publicKeyFilePath); 

     // secret key 
     String secretKeyFilePath = "E:/Programs/Keys/GPG/Secret/private.key"; 
     File secretKeyFile = new File(secretKeyFilePath); 

     // security provider 
     Security.addProvider(new BouncyCastleProvider()); 

     try { 

      // Read the public key 
      FileInputStream pubIn = new FileInputStream(publicKeyFile); 
      PGPPublicKey pgpPubKey = readPublicKey(pubIn); 
      PublicKey pubKey = new JcaPGPKeyConverter().getPublicKey(pgpPubKey); 

      // Read the private key 
      FileInputStream secretIn = new FileInputStream(secretKeyFile); 
      PGPSecretKey pgpSecretKey = readSecretKey(secretIn); 
      PGPPrivateKey pgpPrivKey = pgpSecretKey 
        .extractPrivateKey(new BcPBESecretKeyDecryptorBuilder(
          new BcPGPDigestCalculatorProvider()).build(pass)); 
      PrivateKey privKey = new JcaPGPKeyConverter() 
        .getPrivateKey(pgpPrivKey); 

      Cipher cipher = Cipher.getInstance("RSA"); 

      // Encrypt data 
      byte[] encData = encryptData(cipher, pubKey, new String(
        "#data1\n#data2\n#data3\n").getBytes()); 
      String cryptString = new BASE64Encoder().encode(encData); 

      System.out.println("\n\nEncrypted data=" + cryptString); 

      // Decrypt data 
      byte[] decData = decryptData(cipher, privKey, encData); 
      String decryptString = new BASE64Encoder().encode(decData); 

      System.out.println("\n\nDecrypted data=" + decryptString); 

     } catch (Exception e) { 
      System.out.println("Setup cipher exception"); 
      System.out.println(e.toString()); 
     } 
    } 

    public byte[] encryptData(Cipher cipher, PublicKey pubKey, byte[] clearText) { 

     byte[] encryptedBytes = null; 
     try { 
      cipher.init(Cipher.ENCRYPT_MODE, pubKey); 
      encryptedBytes = cipher.doFinal(clearText); 

     } catch (InvalidKeyException e) { 
      e.printStackTrace(); 
     } catch (IllegalBlockSizeException e) { 
      e.printStackTrace(); 
     } catch (BadPaddingException e) { 
      e.printStackTrace(); 
     } 
     return encryptedBytes; 
    } 

    public byte[] decryptData(Cipher cipher, PrivateKey privKey, byte[] encryptedText) { 

     byte[] decryptedBytes = null; 
     try { 
      cipher.init(Cipher.DECRYPT_MODE, privKey); 
      decryptedBytes = cipher.doFinal(encryptedText); 

     } catch (InvalidKeyException e) { 
      e.printStackTrace(); 
     } catch (IllegalBlockSizeException e) { 
      e.printStackTrace(); 
     } catch (BadPaddingException e) { 
      e.printStackTrace(); 
     } 
     return decryptedBytes; 
    } 

    private static PGPPublicKey readPublicKey(InputStream input) throws IOException, PGPException { 

     PGPPublicKeyRingCollection pgpPub = new PGPPublicKeyRingCollection(PGPUtil.getDecoderStream(input)); 

     Iterator<?> keyRingIter = pgpPub.getKeyRings(); 
     while (keyRingIter.hasNext()) { 
      PGPPublicKeyRing keyRing = (PGPPublicKeyRing) keyRingIter.next(); 

      Iterator<?> keyIter = keyRing.getPublicKeys(); 
      while (keyIter.hasNext()) { 
       PGPPublicKey key = (PGPPublicKey) keyIter.next(); 

       if (key.isEncryptionKey()) { 
        return key; 
       } 
      } 
     } 

     throw new IllegalArgumentException(
       "Can't find encryption key in key ring."); 
    } 

    private static PGPSecretKey readSecretKey(InputStream input) throws IOException, PGPException { 

     PGPSecretKeyRingCollection pgpSec = new PGPSecretKeyRingCollection(PGPUtil.getDecoderStream(input)); 

     Iterator<?> keyRingIter = pgpSec.getKeyRings(); 
     while (keyRingIter.hasNext()) { 
      PGPSecretKeyRing keyRing = (PGPSecretKeyRing) keyRingIter.next(); 

      Iterator<?> keyIter = keyRing.getSecretKeys(); 
      while (keyIter.hasNext()) { 
       PGPSecretKey key = (PGPSecretKey) keyIter.next(); 

       if (key.isSigningKey()) { 
        return key; 
       } 
      } 
     } 

     throw new IllegalArgumentException(
       "Can't find signing key in key ring."); 
    } 

} 

Answer 1

它們是不一樣的，因爲你是base-64編碼解密的結果，而不是解碼爲文本。取而代之的是：

byte[] decData = decryptData(cipher, privKey, encData); 
System.out.println("\n\nDecrypted data=" + new String(decData)); 

使用平臺默認字符編碼是很差的做法。相反，您應該使用特定編碼將文本轉換爲字節，並在解碼字節時使用相同的編碼。

byte[] plaintext = "#data1\n#data2\n#data3\n").getBytes(StandardCharsets.UTF_8); 
... 
String recovered = new String(decData, StandardCharsets.UTF_8);