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Ho recentemente cercato di creare un server/client crittografato SSL in C#.Come identificare il nome del mio server per l'autenticazione del server per client in C#
Ho seguito this tutorial su MSDN, tuttavia, è necessario un certificato da creare per l'utilizzo di server e client utilizzando Makecert.exe così ho trovato un esempio e ha creato il certificato multa:
makecert -sr LocalMachine -ss My -n "CN=Test" -sky exchange -sk 123456 c:/Test.cer
ma ora il problema è avviato il server e aspetta per i clienti, quando il client si connette utilizza il nome della macchina che, per quanto ho potuto capire è il mio IP, in questo caso:
127.0.0.1
, e poi richiede il nome server che deve corrispondere al nome server sul certificato (Test.cer). Ho provato diverse combinazioni (come ad esempio "Test" "LocalMachine", "127.0.0.1", ma non posso sembrare ottenere i clienti dato nome del server per abbinare permettendo così il collegamento L'errore che ottengo è:.
Certificate error: RemoteCertificateNameMismatch, RemoteCertificateChainErrors Exception: the remote certificate is invalid according to the validation procedure
ecco il codice che sto utilizzando differisce dall'esempio MSDN solo nel fatto che assegno il percorso certificato per il server in app e il nome della macchina e il nome del server del cliente troppo:
SslTcpServer .cs
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 = X509Certificate.CreateFromCertFile(certificate);
// 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,
false, SslProtocols.Tls, 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.");
}
}
public static void Main(string[] args)
{
string certificate = "c:/Test.cer";
SslTcpServer.RunServer(certificate);
}
}
}
SslTcpClient.cs
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);
}
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();
}
public static void Main(string[] args)
{
string serverCertificateName = null;
string machineName = null;
/*
// 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];
}*/
machineName = "127.0.0.1";
serverCertificateName = "David-PC";// tried Test, LocalMachine and 127.0.0.1
SslTcpClient.RunClient(machineName, serverCertificateName);
Console.ReadKey();
}
}
}
EDIT:
Il server accetta la connessione client e tutto, ma va in timeout durante l'attesa per il cliente per inviare un messaggio. (Il client solito l'autenticazione con il server a causa del nome del server nel certificato di essere diversa da quella che ho fornito nel client) e questo è il mio pensiero su di essa solo per chiarire
UPDATE:
Secondo una risposta che hanno cambiato il creatore certficiate a:
makecert -sr LocalMachine -ss My -n "CN=localhost" -sky exchange -sk 123456 c:/Test.cer and in my client I have:
machineName = "127.0.0.1";
serverCertificateName = "localhost";// tried Test, LocalMachine and 127.0.0.1
SslTcpClient.RunClient(machineName, serverCertificateName);
ora ottengo l'eccezione:
RemoteCertificateChainErrors Exception: the remote certificate is invalid according to the validation procedure
che sta accadendo qui:
// The server name must match the name on the server certificate.
try
{
sslStream.AuthenticateAsClient(serverName);
}
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. "+ e.Message);
client.Close();
return;
}
Si sta utilizzando un certificato per il cliente? Qual è il valore di 'serverName' nell'ultimo snippet di codice? Inoltre, per favore pubblica il valore di 'sslPolicyErrors' nel metodo di validazione del client. –