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/// <summary>
/// Client pour une connexion TLS
/// </summary>
public class ClientTLS
{
// The following method is invoked by the RemoteCertificateValidationDelegate.
public static bool ValidateServerCertificate(
object sender,
X509Certificate certificate,
X509Chain chain,
SslPolicyErrors sslPolicyErrors)
{
try
{
Console.WriteLine("[ValidateServerCertificate] Begin");
if (sslPolicyErrors == SslPolicyErrors.None)
return true;
Console.WriteLine("Certificate error: {0}", sslPolicyErrors);
return false;
}
catch (Exception ex)
{
Console.WriteLine($"[ValidateServerCertificate] Exception {ex.Message}");
// Do not allow this client to communicate with unauthenticated servers.
return false;
}
}
public static void RunClient(string machineName, string serverName)
{
try
{
using (TcpClient client = new TcpClient(machineName, 8501))
{
using (var sslStream = new SslStream(client.GetStream(), false, new RemoteCertificateValidationCallback(ValidateServerCertificate), null))
{
Console.WriteLine("Client connected.");
X509Store store = new X509Store(StoreName.My, StoreLocation.LocalMachine);
store.Open(OpenFlags.ReadOnly);
sslStream.AuthenticateAsClient(serverName, store.Certificates, SslProtocols.Tls12, false);
Console.WriteLine("SSL authentication completed.");
Console.WriteLine("SSL using local certificate {0}.", sslStream.LocalCertificate.Subject);
Console.WriteLine("SSL using remote certificate {0}.", sslStream.RemoteCertificate.Subject);
var outputMessage = "Hello from the client " + Process.GetCurrentProcess().Id.ToString() + ".";
var outputBuffer = Encoding.UTF8.GetBytes(outputMessage);
sslStream.Write(outputBuffer);
Console.WriteLine("Sent: {0}", outputMessage);
var inputBuffer = new byte[4096];
var inputBytes = 0;
while (inputBytes == 0)
{
inputBytes = sslStream.Read(inputBuffer, 0, inputBuffer.Length);
}
var inputMessage = Encoding.UTF8.GetString(inputBuffer, 0, inputBytes);
Console.WriteLine("Received: {0}", inputMessage);
}
}
}
catch (Exception 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;
}
}
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];
}
RunClient(machineName, serverCertificateName);
return 0;
}
#endregion
} |
