使用C#实现SSLSocket加密通讯

Posted wuyb_2004

tags:

篇首语:本文由小常识网(cha138.com)小编为大家整理,主要介绍了使用C#实现SSLSocket加密通讯相关的知识,希望对你有一定的参考价值。

SSL Socket通讯是对socket的扩展,增加Socket通讯的数据安全性,SSL认证分为单向和双向认证。单向认证只认证服务器端的合法性而不认证客户端的合法性。双向认证是同时认证服务端和客户端。下面我分别说说使用C#实现单向认证和双向认证的过程,并用代码实现。

一、 单向认证

第1步:准备一个数字证书,可以使用如下脚本生成
先进入到vs2005的命令行状态,即:
开始–>程序–>Microsoft Visual Studio 2005–>Visual Studio Tools–>Visual Studio 2005 命令提示
键入: makecert -r -pe -n “CN=TestServer” -ss Root -sky exchange
说明:上面的指令将在创建一个受信任的根证书,
第2步创建服务器端程序,代码如下:
using System;
using System.ServiceModel;
using System.Net;
using System.Net.Sockets;
using System.Net.Security;
using System.Text;
using System.Security.Authentication;
using System.Security.Cryptography.X509Certificates;
using System.IdentityModel.Tokens;
using System.IdentityModel.Selectors;

namespace ConsoleApp

public class Program

static X509Certificate serverCertificate = null;

    public static void RunServer()
    
        TcpListener listener = new TcpListener(IPAddress.Parse("192.168.1.25"), 901);
        listener.Start();
        while (true)
        
            try
            
                Console.WriteLine("Waiting for a client to connect...");
                TcpClient client = listener.AcceptTcpClient();
                ProcessClient(client);
            
            catch
            
            
        
    

    static void ProcessClient(TcpClient client)
    
        SslStream sslStream = new SslStream(client.GetStream(), false);
        try
        
            sslStream.AuthenticateAsServer(serverCertificate, false, SslProtocols.Tls, true);
            DisplaySecurityLevel(sslStream);
            DisplaySecurityServices(sslStream);
            DisplayCertificateInformation(sslStream);
            DisplayStreamProperties(sslStream);

            sslStream.ReadTimeout = 5000;
            sslStream.WriteTimeout = 5000;
            byte[] message = Encoding.UTF8.GetBytes("Hello from the server.");
            Console.WriteLine("Sending hello message.");
            sslStream.Write(message);
            Console.WriteLine("Waiting for client message...");
            while (true)
            
                string messageData = ReadMessage(sslStream);
                Console.WriteLine("Received: 0", messageData);
                if (messageData.ToUpper() == "EXIT")
                    break;
             
        
        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
        
            sslStream.Close();
            client.Close();
        
    

    static string ReadMessage(SslStream sslStream)
    
        byte[] buffer = new byte[2048];
        StringBuilder messageData = new StringBuilder();
        int bytes = -1;
        do
        
            bytes = sslStream.Read(buffer, 0, buffer.Length);
            Decoder decoder = Encoding.UTF8.GetDecoder();
            char[] chars = new char[decoder.GetCharCount(buffer, 0, bytes)];
            decoder.GetChars(buffer, 0, bytes, chars, 0);
            messageData.Append(chars);
            if (messageData.ToString().IndexOf("") != -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.");
        
        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");
    

    public static void Main(string[] args)
    
        try
        
            X509Store store = new X509Store(StoreName.Root);
            store.Open(OpenFlags.ReadWrite);
            // 检索证书 
            X509Certificate2Collection certs = store.Certificates.Find(X509FindType.FindBySubjectName, "TestServer", false); // vaildOnly = true时搜索无结果。
            if (certs.Count == 0) return;

            serverCertificate = certs[0];
            RunServer();
            store.Close(); // 关闭存储区。
        
        catch (Exception ex)
        
            Console.WriteLine(ex.Message);
        
        Console.ReadLine();
    


第3步,创建客户端代码
namespace ConsoleAppClient

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

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)
        
            // Create a TCP/IP client socket.
            // machineName is the host running the server application.
            TcpClient client = new TcpClient(machineName, 901);
            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);
            try
            
                sslStream.AuthenticateAsClient("TestServer");
            
            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);

            messsage = Encoding.UTF8.GetBytes("exit");
            sslStream.Write(messsage);
            sslStream.Flush();
            // 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 void Main(string[] args)
        
            string machineName = null;
            machineName = "192.168.1.25";
            try
            
                RunClient(machineName);
            
            catch (Exception ex)
            
                Console.WriteLine(ex.Message);
            
            Console.ReadLine();
        
    


运行效果如下图:
导致通讯失败可能问题如下:
1)证书没有导入到受信任的根证书列表中;2)证书失效;3)客户端在使用AuthenticateAsClient注册时没有正确使用服务器端证书名称。

二、 双向认证

第1步:创建所需证书,服务器端所需证书同单向认证中的创建过程
先进入到vs2005的命令行状态,即:
开始–>程序–>Microsoft Visual Studio 2005–>Visual Studio Tools–>Visual Studio 2005 命令提示
键入:
makecert -r -pe -n “CN=TestClient” -ss Root -sky exchange
第2步:创建服务端程序
服务端的程序同单向认证的服务器端代码
第3步:创建客户端程序
namespace ConsoleAppClient

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

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)
        
            // Create a TCP/IP client socket.
            // machineName is the host running the server application.
            TcpClient client = new TcpClient(machineName, 901);
            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.

            X509Store store = new X509Store(StoreName.Root);
            store.Open(OpenFlags.ReadWrite);

             检索证书 
            X509Certificate2Collection certs = store.Certificates.Find(X509FindType.FindBySubjectName, "TestClient", false);                
            try
            
                sslStream.AuthenticateAsClient("TestServer", certs, SslProtocols.Tls, false);
            
            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);

            messsage = Encoding.UTF8.GetBytes("exit");
            sslStream.Write(messsage);
            sslStream.Flush();

            // 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 void Main(string[] args)
        
            string machineName = null;
            machineName = "192.168.1.25";
            try
            
                RunClient(machineName);
            
            catch (Exception ex)
            
                Console.WriteLine(ex.Message);
            
            Console.ReadLine();
        
    

以上是关于使用C#实现SSLSocket加密通讯的主要内容,如果未能解决你的问题,请参考以下文章

加密的类型及其相关算法--单向加密

Linux服务及安全管理第八周作业Linux微职位

Linux服务及安全管理第八周作业Linux微职位

C语言通讯录系统——C语言单向链表实现

SSLSocket

加密算法应用 C# code