C＃加密到PHP解密

2 回答

• 5

  由于字符串部分正常，但最后会有乱码，这表明加密中的填充问题需要256字节的精确块 . 我建议在C＃端将填充设置为 PKCS7 （PaddingMode.PKCS7）而不是 Zeros ，PHP将理解没有问题（因为它是该解析器的默认模式） .

  Edit: 哎呀，我没注意到你的PHP中有以下内容：

  $enc = $_COOKIE["MyCookie"];
  

  这是警告 . PHP可能无法按原样获取加密数据，并且正在运行一些urldecode清理 . 您应该打印此变量以查看它与C＃代码发送的内容真正匹配 .

  Edit2:

  通过添加以下内容将空格转换为cookie中缺少的字符：

  str_replace(' ', '+', $enc);
  

  回复于 2024-05-08T00:48:35+08:00
• 19

  对于后人，我在这里放置完整的解决方案 .

  C# Encryption Class

  public static class Encryption
  {
      public static string Encrypt(string prm_text_to_encrypt, string prm_key, string prm_iv)
      {
          var sToEncrypt = prm_text_to_encrypt;
  
          var rj = new RijndaelManaged()
          {
              Padding = PaddingMode.PKCS7,
              Mode = CipherMode.CBC,
              KeySize = 256,
              BlockSize = 256,
          };
  
          var key = Convert.FromBase64String(prm_key);
          var IV = Convert.FromBase64String(prm_iv);
  
          var encryptor = rj.CreateEncryptor(key, IV);
  
          var msEncrypt = new MemoryStream();
          var csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write);
  
          var toEncrypt = Encoding.ASCII.GetBytes(sToEncrypt);
  
          csEncrypt.Write(toEncrypt, 0, toEncrypt.Length);
          csEncrypt.FlushFinalBlock();
  
          var encrypted = msEncrypt.ToArray();
  
          return (Convert.ToBase64String(encrypted));
          }
  
      public static string Decrypt(string prm_text_to_decrypt, string prm_key, string prm_iv)
      {
  
          var sEncryptedString = prm_text_to_decrypt;
  
          var rj = new RijndaelManaged()
          {
              Padding = PaddingMode.PKCS7,
              Mode = CipherMode.CBC,
              KeySize = 256,
              BlockSize = 256,
          };
  
          var key = Convert.FromBase64String(prm_key);
          var IV = Convert.FromBase64String(prm_iv);
  
          var decryptor = rj.CreateDecryptor(key, IV);
  
          var sEncrypted = Convert.FromBase64String(sEncryptedString);
  
          var fromEncrypt = new byte[sEncrypted.Length];
  
          var msDecrypt = new MemoryStream(sEncrypted);
          var csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read);
  
          csDecrypt.Read(fromEncrypt, 0, fromEncrypt.Length);
  
          return (Encoding.ASCII.GetString(fromEncrypt));
          }
  
      public static void GenerateKeyIV(out string key, out string IV)
      {
          var rj = new RijndaelManaged()
          {
              Padding = PaddingMode.PKCS7,
              Mode = CipherMode.CBC,
              KeySize = 256,
              BlockSize = 256,
          };
          rj.GenerateKey();
          rj.GenerateIV();
  
          key = Convert.ToBase64String(rj.Key);
          IV = Convert.ToBase64String(rj.IV);
      }
  }
  

  PHP Decryption Snippet

  <?php
  function decryptRJ256($key,$iv,$encrypted)
  {
      //PHP strips "+" and replaces with " ", but we need "+" so add it back in...
      $encrypted = str_replace(' ', '+', $encrypted);
  
      //get all the bits
      $key = base64_decode($key);
      $iv = base64_decode($iv);
      $encrypted = base64_decode($encrypted);
  
      $rtn = mcrypt_decrypt(MCRYPT_RIJNDAEL_256, $key, $encrypted, MCRYPT_MODE_CBC, $iv);
      $rtn = unpad($rtn);
      return($rtn);
  }
  
  //removes PKCS7 padding
  function unpad($value)
  {
      $blockSize = mcrypt_get_block_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_CBC);
      $packing = ord($value[strlen($value) - 1]);
      if($packing && $packing < $blockSize)
      {
          for($P = strlen($value) - 1; $P >= strlen($value) - $packing; $P--)
          {
              if(ord($value{$P}) != $packing)
              {
                  $packing = 0;
              }
          }
      }
  
      return substr($value, 0, strlen($value) - $packing); 
  }
  ?>
  <pre>
  <?php
  
  $enc = $_COOKIE["MyCookie"];
  
  $ky = ""; //INSERT THE KEY GENERATED BY THE C# CLASS HERE
  $iv = ""; //INSERT THE IV GENERATED BY THE C# CLASS HERE
  
  $json_user = json_decode(decryptRJ256($ky, $iv, $enc), true);
  
  var_dump($json_user);
  
  ?>
  

  回复于 2024-05-08T00:48:35+08:00