Codice sorgente di Bob.cs (esempio CNG)

Aggiornamento: Luglio 2008

L'esempio di comunicazione protetta tramite Cryptography Next Generation (CNG) è costituito da tre applicazioni console: Alice, Bob e Mallory. L'applicazione Bob (file Bob.cs) contiene il codice seguente.

using System;                           // Required for the IDisposable interface
using System.Text;                      // Required for the Encoding class

public partial class CNG_SecureCommunicationExample
{
    static int  MyColor = 2;                        // Bob White displays white text
    static int  OtherColor = 4;                     // Alice Green displays green text

    static void Main()
        {
        InitConsole("Bob White", 610, 5);
        string s = "";
        while (true)
            {
            SplashScreen();
            s = AppControl("receive", "BobControlChannel");
            if ("exit" == s)
                break; 
            Run();
            }
        }          // End Main



    static void Run()
    {
        ASCIIEncoding enc = new ASCIIEncoding();

        InitializeOptions();

        System.Threading.Thread.Sleep(200);
        string NewChannelName = ReceiveChannelName();

        string s;

        using (Communicator Bob = new Communicator("client", NewChannelName))
        {
            Display("Hi, I'm Bob White: My sales associate is Alice Green.\n" +
                    "I think she has a new customer contact for me!\n\n");

            if (3 <= Version)
                {
                Display("\nFirst, Alice will publicaly send me a digital signature key.\n");
                Byte[] DSKey = Bob.ChMgr.ReadMessage();                      // Read the message
                Bob.StoreDSKey(DSKey);

                s = enc.GetString(DSKey);
                if (fVerbose)
                    {
                    Display("Here it is:\n\n");
                    Display(s + "\n\n", 4);
                    }
                }


            if (4 <= Version)
                {
                byte[] DSKey;
                using (ChannelManager ChMgr2 = new ChannelManager("client", "PrivateChannel"))
                DSKey = ChMgr2.ReadMessage();
                Bob.StoreDSKey(DSKey);

                Display("\nNow Alice privately sent me a digital signature key. I will use it instead.\n");
                s = enc.GetString(DSKey);
                if (fVerbose)
                    {
                    Display("Here it is:\n\n");
                    Display(s + "\n\n", 4);
                    }
                }

//-------------------------------------------------------------------------------------------------

            if (2 <= Version)
                {
                Display(sep2, 1);
                Display("Now we will exchange our public cryptographic\n" +              // Send and Receive ECDH public keys
                        "keys through a public channel.\n" +
                        "First, Alice will send me her key.\n\nListening...\n");

                if (!Bob.Send_or_Receive_PublicCryptoKey("receive", OtherColor))    
                    return;

                Display(sep2, 1);
                Display("Next, I will send my public cryptographic key to Alice:\n\nSending...\n");
                Bob.Send_or_Receive_PublicCryptoKey("send", MyColor);
               }

//-------------------------------------------------------------------------------------------------
// Now that all the keys have been transmitted, have a conversation.
            if (1 < Version)
                {
                Display(sep2, 1);
                Display("Now that our keys have been exchanged,\n" +
                       "we can have an encrypted conversation:\n\n", 2);
                Display(sep1, 1);
                }

            Bob.ReceiveMessage();       // Read a message
            Bob.SendMessage("Hi Alice. That is good news. Please send it to me.",true);
            Bob.ReceiveMessage();       // Read a message
            Bob.SendMessage("Thanks, I'll arrange to meet with them.",true);
//-------------------------------------------------------------------------------------------------
            if (Version <= 2)
                Display(sep1,1);

           if (!fVerbose && Version >= 3)
                Display(sep1, 1);

            Display("Would you like to talk to me?\n" +
                    "If yes, go to Alice's window\n" +
                    "and follow the instructions.\n\n",1);
            Display(sep + sep1,1);
            s = "";

            while (true)
                {
                s = Bob.ReceiveMessage();       // Read a message
                if ("" == s)
                    break;
                s = ReadALine(true); 
                if (!Bob.SendMessage(s,false))                // If Alice entered CTRL-C or SYS_CLOSE
                    break;
                if ("" == s)
                    break;
                }
            }        // End using (Communicator Bob)
//-------------------------------------------------------------------------------------------------
        Display(sep1,1);
        }               // End Run method


///////////////////////////////////////////////////////////////////////////////////////////////////
}       // End public partial class CNG_SecureCommunicationExample

Vedere anche

Attività

Procedura: compilare ed eseguire l'esempio CNG

Concetti

Cenni preliminari sul codice sorgente (esempio CNG)

Esempio di comunicazione protetta tramite Cryptography Next Generation (CNG)

Altre risorse

Servizi di crittografia

Cronologia delle modifiche

Data	Cronologia	Motivo
Luglio 2008	Argomento aggiunto.	Miglioramento delle informazioni.