C＃中的数字签名

Question

So I have a server and a clients. And I have a task/problem with security. Conversation between server and client: Client : Give me config file, Server! Server : Sending config file with digital signature Client : Receive data

So, What approach should I choose?

1. Generate private and public keys(server side).
2. Save private key in the xml-file (TIP1)
3. Clients will be spread with public key(which was generate together with private key)

than, when clients will send request to server : 1. Server get private key from xml-file(TIP1) and send config file + digital signature(encrypt by private key) 2. Client receive response from server and verify digital signature by public key

How can I implement this idea in C# ? Keys(private and public) I'll be generate by special program. So private key I'll be save in xml-file.

ADDITIONALLY

I wrote some class that maybe do work that I want :

public class Cryptography
{
    private const string CONTAINER_NAME = "MyContainer";

    private static RSACryptoServiceProvider rsa;
    private static MD5 md5;

    private static void AssignParameter()
    {           
        CspParameters cspParams;
        cspParams = new CspParameters();
        cspParams.KeyContainerName = CONTAINER_NAME;
        cspParams.Flags = CspProviderFlags.UseMachineKeyStore;

        rsa = new RSACryptoServiceProvider(cspParams);
    }

    static Cryptography()
    {
        md5 = MD5.Create();
    }

    public static byte[] CreateSignature(byte[] data, string pathToKey)
    {
        AssignParameter();

        StreamReader reader = new StreamReader(pathToKey);
        string privateKeyXML = reader.ReadToEnd();
        rsa.FromXmlString(privateKeyXML);
        reader.Close();

        RSAPKCS1SignatureFormatter RSAform = new RSAPKCS1SignatureFormatter(rsa);
        RSAform.SetHashAlgorithm("MD5");

        byte[] hashData = md5.ComputeHash(data);

        return RSAform.CreateSignature(hashData);
    }

    public static bool VerifySignature(byte[] originalData, byte[] data, string pathToKey)
    {
        StreamReader reader = new StreamReader(pathToKey);
        string publicKeyXML = reader.ReadToEnd();
        rsa.FromXmlString(publicKeyXML);
        reader.Close();

        RSAPKCS1SignatureDeformatter RSAdeform = new RSAPKCS1SignatureDeformatter(rsa);
        RSAdeform.SetHashAlgorithm("MD5");

        byte[] hashOriginalData = md5.ComputeHash(originalData);

        return RSAdeform.VerifySignature(hashOriginalData, data);
    }

    public static void AssignNewKey()
    {
        AssignParameter();

        StreamWriter writer = new StreamWriter(@"D:\cryptography\privatekey.xml");
        string privatePrivateKeyXML = rsa.ToXmlString(true);
        writer.Write(privatePrivateKeyXML);
        writer.Close();

        writer = new StreamWriter(@"D:\cryptography\publickey.xml");
        string publicOnlyKeyXML = rsa.ToXmlString(false);
        writer.Write(publicOnlyKeyXML);
        writer.Close();

    }

}

What do you think ?

Answer 1

无需重新设计轮子，您可以简单地使用WCF的传输或消息安全性并完成它-除非出于任何原因当然不能使用WCF。