求个C#客户端、Java服务器都支持 RSA/CBC/PKCS1Padding 加解密的代码，实现互加密互解

ilovecomputer66

网上找的教程，几乎都不考虑分段加密解密，数据大一点点，就不能用（比如，都是抄这个没考虑分段加密的） https://blog.csdn.net/thc1987/article/details/81383365

我只找到客户端分段加密的，但是代码有缺陷，只能用ECB，不能CBC，否则报错（不知为何）  https://blog.csdn.net/Qin066/article/details/121856447

java的木有找到支持分段加密，并且和上面C#代码能配合的

ttyy008

Bouncy Castle这个库，参考：https://www.bouncycastle.org/csharp/index.html

ilovecomputer66

ttyy008 发表于 2023-2-16 14:19
Bouncy Castle这个库，参考：https://www.bouncycastle.org/csharp/index.html

额，我上面那个  https://blog.csdn.net/Qin066/article/details/121856447

就是用这个库呀，现在网上资料全都用这个的。但问题不是在用什么库，而是怎么用。我没有找到用这个库，可以用CBC方式的写法，都是ECB的（已被证明不安全，不推荐）

ttyy008

试试吧

[C#] 纯文本查看 复制代码

using Org.BouncyCastle.Crypto;
using Org.BouncyCastle.Crypto.Engines;
using Org.BouncyCastle.Crypto.Modes;
using Org.BouncyCastle.Crypto.Paddings;
using Org.BouncyCastle.Crypto.Parameters;
using System;
using System.Text;

public class Program
{
    static void Main(string[] args)
    {      
        byte[] key = Encoding.UTF8.GetBytes("0123456789abcdef");
        byte[] iv = Encoding.UTF8.GetBytes("fedcba9876543210");

      
        string plaintext = "Hello, world!";
      
        byte[] ciphertext = EncryptCBC(Encoding.UTF8.GetBytes(plaintext), key, iv);
      
        string ciphertextString = Convert.ToBase64String(ciphertext);
        Console.WriteLine("Ciphertext: " + ciphertextString);

     
        byte[] decrypted = DecryptCBC(ciphertext, key, iv);
       
        string decryptedString = Encoding.UTF8.GetString(decrypted);
        Console.WriteLine("Decrypted: " + decryptedString);
    }

    public static byte[] EncryptCBC(byte[] plaintext, byte[] key, byte[] iv)
    {        
        IBlockCipher cipher = new AesFastEngine();
        cipher = new CbcBlockCipher(cipher);
        cipher = new PaddedBufferedBlockCipher(cipher);

        cipher.Init(true, new ParametersWithIV(new KeyParameter(key), iv));
       
        byte[] output = new byte[cipher.GetOutputSize(plaintext.Length)];
        int bytesProcessed = cipher.ProcessBytes(plaintext, 0, plaintext.Length, output, 0);
        cipher.DoFinal(output, bytesProcessed);

        return output;
    }

    public static byte[] DecryptCBC(byte[] ciphertext, byte[] key, byte[] iv)
    {       
        IBlockCipher cipher = new AesFastEngine();
        cipher = new CbcBlockCipher(cipher);
        cipher = new PaddedBufferedBlockCipher(cipher);

        cipher.Init(false, new ParametersWithIV(new KeyParameter(key), iv));
       
        byte[] output = new byte[cipher.GetOutputSize(ciphertext.Length)];
        int bytesProcessed = cipher.ProcessBytes(ciphertext, 0, ciphertext.Length, output, 0);
        cipher.DoFinal(output, bytesProcessed);

        return output;
    }
}