Tls 1.2连接可以在没有私钥和公钥的情况下工作吗?

时间:2020-09-28 12:16:10

标签: .net ssl ssl-certificate tls1.2 winsock

我正在尝试在服务器和客户端之间建立TCP / IP连接,并且为了确保安全连接,应该启用TLS 1.2。该证书是使用开放SSL创建的,某些消息人士称,这是创建用于测试目的的自签名证书的最佳方法。以下是我使用的MSDN代码。我已将证书放在服务器存储中以供使用。当我尝试从服务器端进行侦听时,我可以从客户端进行连接,并且正在传输数据。但是我觉得我在这里错过了很多事情。

我是套接字连接实现的新手。最初,我有很多问题。在网上冲浪可以解决一些问题,但我却找不到其中的一些答案。以下是我的疑问。

  1. 此处的私钥和公钥是什么?我没有在任何地方使用它。但是它似乎以某种方式起作用。请让我知道如何将其添加到以下代码中?
  2. 我可以看到服务器正在将带有证书信息的消息带给正在通过AuthenticateAsClient方法验证的客户端。这足以检查服务器的真实性吗?
  3. 如何使用AuthenticateAsServer验证客户端?我们需要在客户端创建一个新的证书还是可以使用相同的旧证书?
  4. 如何验证我的实施是否正常?如何确保通话安全?
  5. 什么是数字证书?它与普通证书有何不同?何时使用?

服务器端代码:

using System;
using System.Collections;
using System.Net;
using System.Net.Sockets;
using System.Net.Security;
using System.Security.Authentication;
using System.Text;
using System.Security.Cryptography.X509Certificates;
using System.IO;

namespace Examples.System.Net
{
    public sealed class SslTcpServer
    {
        static X509Certificate serverCertificate = null;
        // The certificate parameter specifies the name of the file
        // containing the machine certificate.
        public static void RunServer(string certificate)
        {
           serverCertificate = "getting the certificate from the store"
            
            // Create a TCP/IP (IPv4) socket and listen for incoming connections.
            TcpListener listener = new TcpListener(IPAddress.Any, 8080);
            listener.Start();
            while (true)
            {
                Console.WriteLine("Waiting for a client to connect...");
                // Application blocks while waiting for an incoming connection.
                // Type CNTL-C to terminate the server.
                TcpClient client = listener.AcceptTcpClient();
                ProcessClient(client);
            }
        }
        static void ProcessClient (TcpClient client)
        {
            // A client has connected. Create the
            // SslStream using the client's network stream.
            SslStream sslStream = new SslStream(
                client.GetStream(), false);
            // Authenticate the server but don't require the client to authenticate.
            try
            {
                sslStream.AuthenticateAsServer(serverCertificate, clientCertificateRequired: false, SslProtocols.Tls12, checkCertificateRevocation: true);

                // Display the properties and settings for the authenticated stream.
                DisplaySecurityLevel(sslStream);
                DisplaySecurityServices(sslStream);
                DisplayCertificateInformation(sslStream);
                DisplayStreamProperties(sslStream);

                // Set timeouts for the read and write to 5 seconds.
                sslStream.ReadTimeout = 5000;
                sslStream.WriteTimeout = 5000;
                // Read a message from the client.
                Console.WriteLine("Waiting for client message...");
                string messageData = ReadMessage(sslStream);
                Console.WriteLine("Received: {0}", messageData);

                // Write a message to the client.
                byte[] message = Encoding.UTF8.GetBytes("Hello from the server.<EOF>");
                Console.WriteLine("Sending hello message.");
                sslStream.Write(message);
            }
            catch (AuthenticationException e)
            {
                Console.WriteLine("Exception: {0}", e.Message);
                if (e.InnerException != null)
                {
                    Console.WriteLine("Inner exception: {0}", e.InnerException.Message);
                }
                Console.WriteLine ("Authentication failed - closing the connection.");
                sslStream.Close();
                client.Close();
                return;
            }
            finally
            {
                // The client stream will be closed with the sslStream
                // because we specified this behavior when creating
                // the sslStream.
                sslStream.Close();
                client.Close();
            }
        }
        static string ReadMessage(SslStream sslStream)
        {
            // Read the  message sent by the client.
            // The client signals the end of the message using the
            // "<EOF>" marker.
            byte [] buffer = new byte[2048];
            StringBuilder messageData = new StringBuilder();
            int bytes = -1;
            do
            {
                // Read the client's test message.
                bytes = sslStream.Read(buffer, 0, buffer.Length);

                // Use Decoder class to convert from bytes to UTF8
                // in case a character spans two buffers.
                Decoder decoder = Encoding.UTF8.GetDecoder();
                char[] chars = new char[decoder.GetCharCount(buffer,0,bytes)];
            decoder.GetChars(buffer, 0, bytes, chars,0);
            messageData.Append (chars);
            // Check for EOF or an empty message.
            if (messageData.ToString().IndexOf("<EOF>") != -1)
            {
                break;
            }
        } while (bytes !=0);

        return messageData.ToString();
    }
     static void DisplaySecurityLevel(SslStream stream)
     {
        Console.WriteLine("Cipher: {0} strength {1}", stream.CipherAlgorithm, stream.CipherStrength);
        Console.WriteLine("Hash: {0} strength {1}", stream.HashAlgorithm, stream.HashStrength);
        Console.WriteLine("Key exchange: {0} strength {1}", stream.KeyExchangeAlgorithm, stream.KeyExchangeStrength);
        Console.WriteLine("Protocol: {0}", stream.SslProtocol);
     }
     static void DisplaySecurityServices(SslStream stream)
     {
        Console.WriteLine("Is authenticated: {0} as server? {1}", stream.IsAuthenticated, stream.IsServer);
        Console.WriteLine("IsSigned: {0}", stream.IsSigned);
        Console.WriteLine("Is Encrypted: {0}", stream.IsEncrypted);
     }
     static void DisplayStreamProperties(SslStream stream)
     {
        Console.WriteLine("Can read: {0}, write {1}", stream.CanRead, stream.CanWrite);
        Console.WriteLine("Can timeout: {0}", stream.CanTimeout);
     }
    static void DisplayCertificateInformation(SslStream stream)
    {
        Console.WriteLine("Certificate revocation list checked: {0}", stream.CheckCertRevocationStatus);

        X509Certificate localCertificate = stream.LocalCertificate;
        if (stream.LocalCertificate != null)
        {
            Console.WriteLine("Local cert was issued to {0} and is valid from {1} until {2}.",
                localCertificate.Subject,
                localCertificate.GetEffectiveDateString(),
                localCertificate.GetExpirationDateString());
         } else
        {
            Console.WriteLine("Local certificate is null.");
        }
        // Display the properties of the client's certificate.
        X509Certificate remoteCertificate = stream.RemoteCertificate;
        if (stream.RemoteCertificate != null)
        {
        Console.WriteLine("Remote cert was issued to {0} and is valid from {1} until {2}.",
            remoteCertificate.Subject,
            remoteCertificate.GetEffectiveDateString(),
            remoteCertificate.GetExpirationDateString());
        } else
        {
            Console.WriteLine("Remote certificate is null.");
        }
    }
    private static void DisplayUsage()
    {
        Console.WriteLine("To start the server specify:");
        Console.WriteLine("serverSync certificateFile.cer");
        Environment.Exit(1);
    }
    public static int Main(string[] args)
    {
        string certificate = null;
        if (args == null ||args.Length < 1 )
        {
            DisplayUsage();
        }
        certificate = args[0];
        SslTcpServer.RunServer (certificate);
        return 0;
    }
}

}

客户端代码:

using System;
using System.Collections;
using System.Net;
using System.Net.Security;
using System.Net.Sockets;
using System.Security.Authentication;
using System.Text;
using System.Security.Cryptography.X509Certificates;
using System.IO;

namespace Examples.System.Net
{
    public class SslTcpClient
    {
        private static Hashtable certificateErrors = new Hashtable();

        // The following method is invoked by the RemoteCertificateValidationDelegate.
        public static bool ValidateServerCertificate(
              object sender,
              X509Certificate certificate,
              X509Chain chain,
              SslPolicyErrors sslPolicyErrors)
        {
           if (sslPolicyErrors == SslPolicyErrors.None)
                return true;

            Console.WriteLine("Certificate error: {0}", sslPolicyErrors);

            // Do not allow this client to communicate with unauthenticated servers.
            return false;
        }
        public static void RunClient(string machineName, string serverName)
        {
            // Create a TCP/IP client socket.
            // machineName is the host running the server application.
            TcpClient client = new TcpClient(machineName,8080);
            Console.WriteLine("Client connected.");
            // Create an SSL stream that will close the client's stream.
            SslStream sslStream = new SslStream(
                client.GetStream(),
                false,
                new RemoteCertificateValidationCallback (ValidateServerCertificate),
                null
                );
            // The server name must match the name on the server certificate.
            try
            {
                sslStream.AuthenticateAsClient(serverName, null, SslProtocols.Tls12, true);
            }
            catch (AuthenticationException e)
            {
                Console.WriteLine("Exception: {0}", e.Message);
                if (e.InnerException != null)
                {
                    Console.WriteLine("Inner exception: {0}", e.InnerException.Message);
                }
                Console.WriteLine ("Authentication failed - closing the connection.");
                client.Close();
                return;
            }
            // Encode a test message into a byte array.
            // Signal the end of the message using the "<EOF>".
            byte[] messsage = Encoding.UTF8.GetBytes("Hello from the client.<EOF>");
            // Send hello message to the server.
            sslStream.Write(messsage);
            sslStream.Flush();
            // Read message from the server.
            string serverMessage = ReadMessage(sslStream);
            Console.WriteLine("Server says: {0}", serverMessage);
            // Close the client connection.
            client.Close();
            Console.WriteLine("Client closed.");
        }
        static string ReadMessage(SslStream sslStream)
        {
            // Read the  message sent by the server.
            // The end of the message is signaled using the
            // "<EOF>" marker.
            byte [] buffer = new byte[2048];
            StringBuilder messageData = new StringBuilder();
            int bytes = -1;
            do
            {
                bytes = sslStream.Read(buffer, 0, buffer.Length);

                // Use Decoder class to convert from bytes to UTF8
                // in case a character spans two buffers.
                Decoder decoder = Encoding.UTF8.GetDecoder();
                char[] chars = new char[decoder.GetCharCount(buffer,0,bytes)];
                decoder.GetChars(buffer, 0, bytes, chars,0);
                messageData.Append (chars);
                // Check for EOF.
                if (messageData.ToString().IndexOf("<EOF>") != -1)
                {
                    break;
                }
            } while (bytes != 0);

            return messageData.ToString();
        }
        private static void DisplayUsage()
        {
            Console.WriteLine("To start the client specify:");
            Console.WriteLine("clientSync machineName [serverName]");
            Environment.Exit(1);
        }
        public static int Main(string[] args)
        {
            string serverCertificateName = null;
            string machineName = null;
            if (args == null ||args.Length <1 )
            {
                DisplayUsage();
            }
            // User can specify the machine name and server name.
            // Server name must match the name on the server's certificate.
            machineName = args[0];
            if (args.Length <2 )
            {
                serverCertificateName = machineName;
            }
            else
            {
                serverCertificateName = args[1];
            }
            SslTcpClient.RunClient (machineName, serverCertificateName);
            return 0;
        }
    }
}

0 个答案:

没有答案