在.NET Core 里使用 BouncyCastle 的DES加密算法

.NET Core上面的DES等加密算法要等到1.2 才支持，我们可是急需这个算法的支持，文章《使用 JavaScriptService 在.NET Core 里实现DES加密算法》需要用Nodejs，很多人觉得这个有点不好，今天就给大家介绍下BouncyCastle （Portable.BouncyCastle）https://www.nuget.org/packages/Portable.BouncyCastle/库为我们提供的原生的.NET Core的支持库的Des算法。BouncyCastle的文档比较少，折腾了好久才写出了.NET 代码等价的一个封装。

public class TDesbouncy
{

IBlockCipher engine = new DesEngine();

/// <summary>
/// 使用DES加密，key输入密码的时候，必须使用英文字符，区分大小写，且字符数量是8个，不能多也不能少
/// </summary>
/// <param name="plainText">需要加密的字符串</param>
/// <param name="keys">加密字符串的密钥</param>
/// <returns>加密后的字符串</returns>
public string Encrypt(string keys, string plainText)
{

byte[] ptBytes = Encoding.UTF8.GetBytes(plainText);
byte[] rv = Encrypt(keys, ptBytes);
StringBuilder ret = new StringBuilder();
foreach (byte b in rv)
{
ret.AppendFormat("{0:X2}", b);
}
return ret.ToString();
}

private byte[] Encrypt(string keys, byte[] ptBytes)
{
byte[] key = Encoding.UTF8.GetBytes(keys);
BufferedBlockCipher cipher = new PaddedBufferedBlockCipher(new CbcBlockCipher(engine),new Pkcs7Padding());
cipher.Init(true, new ParametersWithIV(new DesParameters(key),key));
byte[] rv = new byte[cipher.GetOutputSize(ptBytes.Length)];
int tam = cipher.ProcessBytes(ptBytes, 0, ptBytes.Length, rv, 0);

cipher.DoFinal(rv, tam);
return rv;
}

/// <summary>
/// 使用DES解密，key输入密码的时候，必须使用英文字符，区分大小写，且字符数量是8个，不能多也不能少
/// </summary>
/// <param name="cipherText">需要加密的字符串</param>
/// <param name="keys">加密字符串的密钥</param>
/// <returns>解密后的字符串</returns>
public string Decrypt(string keys, string cipherText)
{
byte[] inputByteArray = new byte[cipherText.Length / 2];
for (int x = 0; x < cipherText.Length / 2; x++)
{
int i = (Convert.ToInt32(cipherText.Substring(x * 2, 2), 16));
inputByteArray[x] = (byte)i;
}
var rv = Decrypt(keys, inputByteArray);

return Encoding.UTF8.GetString(rv);

}

private byte[] Decrypt(string keys, byte[] cipherText)
{
byte[] key = Encoding.UTF8.GetBytes(keys);
BufferedBlockCipher cipher = new PaddedBufferedBlockCipher(new CbcBlockCipher(engine));
cipher.Init(false, new ParametersWithIV(new DesParameters(key), key));
byte[] rv = new byte[cipher.GetOutputSize(cipherText.Length)];
int tam = cipher.ProcessBytes(cipherText, 0, cipherText.Length, rv, 0);

cipher.DoFinal(rv, tam);

return rv;
}

}

public static void Main(string[] args)
{

Encoding.RegisterProvider(CodePagesEncodingProvider.Instance);

string key = "geffzhan";
string content = "This project.config whoopla is a mess. So what they mean by .NetCore, you still have to reference everything correctly";

TDesbouncy bouncy = new TDesbouncy();

var encrypt = bouncy.Encrypt(key, content);
Console.WriteLine(encrypt);

string descontent = bouncy.Decrypt(key, encrypt);
Console.WriteLine(descontent);
}

【本文由“oSeHTs-IsJAOjA2yk-lgG7H6ivAU@wechat.sohu.com”发布，2017年5月23日】