java - 启用 RSA 的简单 Java 聊天 - 不是 PKCS#1 block 类型 2 或零填充

Question

我创建了一个简单的 Java 聊天应用程序。下面是下面的内容

运行 ChatClient.java - 显示用户输入用户名的对话框。然后生成私钥和公钥并存储在C:/username/publickey,C:/username/privatekey中。

当我们再次运行 ChatClient.java 时，会重复上述步骤。

然后用户1使用用户2公钥以加密形式向用户2发送消息(工作正常)(加密后，消息存储在文本文件中)然后用户2单击解密按钮解密文本(从文件中读取加密文本)使用用户 2 私钥然后显示在文本区域中。

当我尝试解密时，出现“Not PKCS#1 block type 2 or Zero padding”异常

public static byte[] encrypt(String text, PublicKey key) throws {
    // get an RSA cipher object and print the provider
    final Cipher cipher = Cipher.getInstance(ALGORITHM);
    // encrypt the plain text using the public key
    cipher.init(Cipher.ENCRYPT_MODE, key);
    byte[] cipherText = cipher.doFinal(text.getBytes("UTF8"));
    return org.apache.commons.codec.binary.Base64.encodeBase64(cipherText);
}

public static String decrypt(String text, PrivateKey key) throws  {
    byte[] dectyptedText = null;

      // get an RSA cipher object and print the provider
      final Cipher cipher = Cipher.getInstance(ALGORITHM);

      // decrypt the text using the private key
     cipher.init(Cipher.DECRYPT_MODE, key);
     byte[] byteCipherText =org.apache.commons.codec.binary.Base64.decodeBase64(text): 
     byte[] cipherData = cipher.doFinal(byteCipherText);
     return new String(dectyptedText);  
}

private void btnDecryptActionPerformed(ActionEvent evt) throws  {
    String name11 = this.getTitle();
    String test90 = null;
    String PRIVATE_KEY_FILE = "C:/keys/"+name11+"/private.key";
    BufferedReader in = null;
    try {
        in = new BufferedReader(new FileReader("cipher.txt"));
    } catch (FileNotFoundException e1) {
        // TODO Auto-generated catch block
        e1.printStackTrace();
    }
    try {
        while(in.ready())
        {
            String stest= in.readLine();
            test90 = stest;


        }
    } catch (IOException e1) {
        // TODO Auto-generated catch block
        e1.printStackTrace();
    }

    ObjectInputStream inputStream = null;
    try {
    inputStream = new ObjectInputStream(new FileInputStream(PRIVATE_KEY_FILE));
    } catch (FileNotFoundException e1) {
        // TODO Auto-generated catch block
        e1.printStackTrace();
    } catch (IOException e1) {
        // TODO Auto-generated catch block
        e1.printStackTrace();
    }
    PrivateKey privateKey = null;
    try {
        privateKey = (PrivateKey) inputStream.readObject();
    } catch (ClassNotFoundException e1) {
        // TODO Auto-generated catch block
        e1.printStackTrace();
    } catch (IOException e1) {
        // TODO Auto-generated catch block
        e1.printStackTrace();
    }
    try {
    inputStream = new ObjectInputStream(new FileInputStream(PRIVATE_KEY_FILE));
    } catch (FileNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    try {
        PrivateKey privatekey = (PrivateKey) inputStream.readObject();
    } catch (ClassNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } 
    String plainText;

//  byte[] test100 = test90.getBytes();
//  out.println(test100);
    plainText = decrypt(test90, privateKey); (Getting Error Here)
    decryptText.append(plainText);
} 

Answer 1

下面突出显示的代码表示 test90 仅包含 cipher.txt 文件中的最后一行。 cipher.txt 仅包含 1 行吗？如果您想读入所有内容，则需要在读入时连接每一行。

while(in.ready())
{
    String stest= in.readLine();
    test90 = stest;
}

在 decrypt 方法中 System.out 变量 test90 也是一个好主意，以确保您获得预计 Base64 数据将被解密。