.Net中的MCRYPT

Question

我在一端使用PHP解密算法，在另一端使用.Net加密算法。我在PHP代码中使用mcrypt_decrypt进行解密，并在.Net中寻找mcrypt_encrypt的等价物。更具体地说，我想要转换成.Net的PHP代码如下：

$cipher_alg = MCRYPT_RIJNDAEL_128;
$iv = mcrypt_create_iv ( mcrypt_get_iv_size ( $cipher_alg, MCRYPT_MODE_ECB ), MCRYPT_RAND );

$encrypted_string = mcrypt_encrypt ( $cipher_alg, $sessionkey, $string, MCRYPT_MODE_CBC, $iv );
$hex_encrypted_string = bin2hex ( $encrypted_string );

在.Net中有没有mcrypt_encrypt的等价物？

Answer 1

我已经和a solution in my blog出来了。

以下是摘录：

    private static string CreateEncryptedString(string myString, string hexiv, string key)
    {
        RijndaelManaged alg = new RijndaelManaged();
        alg.Padding = PaddingMode.Zeros;
        alg.Mode = CipherMode.CBC;
        alg.BlockSize = 16 * 8;
        alg.Key = ASCIIEncoding.UTF8.GetBytes(key);
        alg.IV = StringToByteArray(hexiv);
        ICryptoTransform encryptor = alg.CreateEncryptor(alg.Key, alg.IV);

        MemoryStream msStream = new MemoryStream();
        CryptoStream mCSWriter = new CryptoStream(msStream, encryptor, CryptoStreamMode.Write);
        StreamWriter mSWriter = new StreamWriter(mCSWriter);
        mSWriter.Write(myString);
        mSWriter.Flush();
        mCSWriter.FlushFinalBlock();

        var EncryptedByte = new byte[msStream.Length];
        msStream.Position = 0;
        msStream.Read(EncryptedByte, 0, (int)msStream.Length);

        return ByteArrayToHexString(EncryptedByte);

    }

    public static byte[] StringToByteArray(String hex)
    {
        int NumberChars = hex.Length;
        byte[] bytes = new byte[NumberChars / 2];
        for (int i = 0; i < NumberChars; i += 2)
            bytes[i / 2] = Convert.ToByte(hex.Substring(i, 2), 16);
        return bytes;
    }

    public static string ByteArrayToHexString(byte[] ba)
    {
        StringBuilder hex = new StringBuilder(ba.Length * 2);
        foreach (byte b in ba)
            hex.AppendFormat("{0:x2}", b);
        return hex.ToString();
    }

有一件事需要注意。密钥大小必须为16，即密钥参数必须为16个字符的字符串。否则加密将不起作用，并将抛出CryptographicException。

在PHP端，下面是如何进行解码的：

$cipher_alg = MCRYPT_RIJNDAEL_128;
$decrypted_string = mcrypt_decrypt($cipher_alg, $key, 
$encrypted_string , MCRYPT_MODE_CBC, trim(hex2bin(trim($hexiv))));

Answer 2

没有直接的等价物，但支持128位Rijndael (可能还有您想要的大多数其他密码)。有关详细信息和示例，请参阅Rijndael类。

基本上，框架的加密部分是基于您指定基类(CryptoStream、SymmetricAlgorithm等)的适当实例，而不是通过名称指定密码-但您应该能够执行所需的操作。