.NET Private Key Rsa Encryption

2019-03-10 02:53发布

问题:

I need to encrypt a string using an RSA 1.5 algorithm. I have been provided with a private key. However, I cannot for the life of me figure out how to add this key to the class. It seems as tho the key needs to be of type RSAParameter stuct. However this requires a set of values I have not been given such as Modulus, Exponent, P, Q, etc.. All I have is the private key. Can anyone help?

回答1:

You should be aware of the Bouncycastle C# library. There are in particular two very useful classes: Org.BouncyCastle.OpenSsl.PemReader which will convert from the openssl style key you have to a bouncycastle key object, and Org.BouncyCastle.Security.DotNetUtilities, which will convert a bouncycastle key to a .NET RSAParameters object.

Here is a tiny bit of untested code that shows how to use it

using System;
using System.IO;
using System.Security.Cryptography;
using Org.BouncyCastle.OpenSsl;
using Org.BouncyCastle.Crypto;
using Org.BouncyCastle.Security;
using Org.BouncyCastle.Crypto.Parameters;

namespace RSAOpensslToDotNet
{
    class Program
    {
        static void Main(string[] args)
        {
            StreamReader sr = new StreamReader("../../privatekey.pem");
            PemReader pr = new PemReader(sr);
            AsymmetricCipherKeyPair KeyPair = (AsymmetricCipherKeyPair)pr.ReadObject();
            RSAParameters rsa = DotNetUtilities.ToRSAParameters((RsaPrivateCrtKeyParameters)KeyPair.Private);
        }
    }
}


回答2:

I guess that is what are you looking for:

    // Import ASymmetric RSA Key from a system file.
    public static RSAParameters ImportRSAKey(String fileName)
    {

        // Create a stream to a the specified system file.
        Stream fileStream = new FileStream(fileName, FileMode.Open, FileAccess.Read);

        // Extract/Deserialize the key from the file.
        IFormatter soapFormatter = new SoapFormatter();            
        RSAParameters rsaParameter = 
           (RSAParameters) soapFormatter.Deserialize(fileStream);

        // Close the file stream.
        fileStream.Close();

        return rsaParameter;

    }

To generate a new key, you can use RSACryptoServiceProvider.ExportParameters method.


Refer to the following:

RSAParameters Structure