/// <summary> /// Closes the stream and optionally closes the underlying <see cref="SecureSocket"/>. /// </summary> /// <remarks> /// The Close method frees resources used by the SecureNetworkStream instance and, if the SecureNetworkStream owns the underlying socket, closes the underlying socket. /// </remarks> public override void Close() { if (m_OwnsSocket) { try { Socket.Shutdown(SocketShutdown.Both); } catch { } finally { Socket.Close(); } } }
private void DownloadFile(Url url, int choice) { SecurityOptions options = new SecurityOptions(SecureProtocol.None);; m_Socket = new SecureSocket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp, options); // connect to the FTP server using a normal TCP connection m_Socket.Connect(new IPEndPoint(Dns.GetHostEntry(url.Host).AddressList[0], url.Port)); // wait for the server hello ReceiveReply(); // if the user selected to use the AUTH command.. if (choice == 2) { // ..send the command to the server and start the SSL handshake DoAuthCommand(url.Host); } // log on and quit if (!SendCommand("USER " + url.Username)) return; if (!SendCommand("PASS " + url.Password)) return; if (!SendCommand("QUIT")) return; // clean up m_Socket.Shutdown(SocketShutdown.Both); m_Socket.Close(); }
public void Start() { try { // ask the user for SMTP server, port and the type of connection Console.Write("Host to connect to: "); string server = Console.ReadLine().Trim(); Console.Write("Port: "); string port = Console.ReadLine().Trim(); Console.Write("Connection type [0 = normal connection, 1 = direct TLS connection, 2 = indirect TLS connection (using STARTTLS command)]: "); string type = Console.ReadLine().Trim(); if (Array.IndexOf(new string[]{"0", "1", "2"}, type) == -1) { Console.WriteLine("Invalid connection type."); return; } Console.WriteLine("Please enter the email address you wish to send an email to:"); string address = Console.ReadLine().Trim(); // create a new SecurityOptions instance SecurityOptions options = new SecurityOptions(SecureProtocol.None); // allow only secure ciphers to be used. Currently, the seure ciphers are: // the AES algorithm [128 or 256 bit keys], the RC4 algorithm [128 bit keys] // or TipleDES [168 bit keys] options.AllowedAlgorithms = SslAlgorithms.SECURE_CIPHERS; // the SecureSocket should be a client socket options.Entity = ConnectionEnd.Client; // we will use manual verification of the server certificate options.VerificationType = CredentialVerification.Manual; // when the server certificate is receives, the SecureSocket should call // the OnVerify method options.Verifier = new CertVerifyEventHandler(OnVerify); // use the default flags options.Flags = SecurityFlags.Default; // the common name is the domain name or IP address of the server options.CommonName = server; // if the user chose a direct TLS connection, set the protocol to TLS1 if (type == "1") { options.Protocol = SecureProtocol.Tls1; } // create the new secure socket Connection = new SecureSocket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp, options); // connect to the SMTP server Connection.Connect(new IPEndPoint(Dns.GetHostEntry(server).AddressList[0], int.Parse(port))); // wait for the server hello message if (!IsReplyOK(Receive())) { Console.WriteLine("Server disallowed connection."); return; } // if the user selected an indirect TLS connection, issue // a EHLO command. Otherwise, stick to the standard HELO command. if (type == "2") // STARTTLS connection Send("EHLO SmtpClient.Mentalis.org\r\n"); else Send("HELO SmtpClient.Mentalis.org\r\n"); if (!IsReplyOK(Receive())) { Console.WriteLine("HELLO failed."); return; } // if the user selected an indirect TLS connection, issue // the STARTTLS command if (type == "2") { // send the STARTTLS command to the server Send("STARTTLS\r\n"); // make sure the server supports the STARTTLS command if (!IsReplyOK(Receive())) { Console.WriteLine("STARTTLS failed."); return; } // change the protocol from SecureProtocol.None // to SecureProtocol.Tls1 options.Protocol = SecureProtocol.Tls1; // start the TLS handshake Connection.ChangeSecurityProtocol(options); // after this line, we're using an encrypted TLS connection } // from here on, act as if the SecureSocket is a normal Socket Send("MAIL FROM: [email protected]\r\n"); // [email protected] is not a real email address if (!IsReplyOK(Receive())) { Console.WriteLine("MAIL FROM failed."); return; } Send("RCPT TO:" + address + "\r\n"); if (!IsReplyOK(Receive())) { Console.WriteLine("RCPT TO failed."); return; } Send("DATA\r\n"); if (!IsReplyOK(Receive())) { Console.WriteLine("DATA failed."); return; } Send(TestMail.Replace("#ADDRESS#", address) + "\r\n.\r\n"); if (!IsReplyOK(Receive())) { Console.WriteLine("Sending of e-mail failed."); return; } Send("QUIT\r\n"); if (!IsReplyOK(Receive())) { Console.WriteLine("QUIT failed."); } Connection.Shutdown(SocketShutdown.Both); } catch (Exception e) { Console.WriteLine("An error occurred [" + e.Message + "]"); Console.WriteLine(e); } finally { if (Connection != null) { Connection.Close(); } } }
/// <summary> /// Download a file using the synchronous Socket methods. /// </summary> /// <param name="url">The URL to download. /// </param> /// <param name="sp">The protocol to use.</param> protected void DownloadFile(Url url, SecureProtocol sp) { string request = GetHttpRequest(url); // holds the HTTP request for the given URL SecureSocket s; try { // First we create a new SecurityOptions instance // SecurityOptions objects hold information about the security // protocols the SecureSocket should use and how the SecureSocket // should react in certain situations. SecurityOptions options = new SecurityOptions(sp); // The Certificate field holds a certificate associated with // a client [you, for instance]. Because client certificates // are not often used for HTTP over SSL or TLS, we'll simply // set this field to a null reference. options.Certificate = null; // The Entity specifies whether the SecureSocket should act // as a client socket or as a server socket. In this case, // it should act as a client socket. options.Entity = ConnectionEnd.Client; // The CommonName field specifies the name of the remote // party we're connecting to. This is usually the domain name // of the remote host. options.CommonName = url.Host; // The VerificationType field specifies how we intend to verify // the certificate. In this case, we tell the SecureSocket that // we will manually verify the certificate. Look in the documentation // for other options. options.VerificationType = CredentialVerification.Manual; // When specifying the CredentialVerification.Manual option, we // must also specify a CertVerifyEventHandler delegate that will // be called when the SecureSocket receives the remote certificate. // The Verifier field holds this delegate. If no manual verification // is done, this field can be set to a null reference. options.Verifier = new CertVerifyEventHandler(OnVerify); // The Flags field specifies which flags should be used for the // connection. In this case, we will simply use the default behavior. options.Flags = SecurityFlags.Default; // Allow only secure ciphers to be used. If the server only supports // weak encryption, the connections will be shut down. options.AllowedAlgorithms = SslAlgorithms.SECURE_CIPHERS; // create a new SecureSocket instance and initialize it with // the security options we specified above. s = new SecureSocket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp, options); // connect to the remote host s.Connect(new IPEndPoint(Dns.GetHostEntry(url.Host).AddressList[0], url.Port)); } catch (Exception e) { Console.WriteLine("Exception occurred while connecting: " + e.ToString()); return; } // send the HTTP request to the remote host Console.Write("HTTP Query string:\r\n------------------\r\n" + request); try { byte[] reqBytes = Encoding.ASCII.GetBytes(request); int sent = s.Send(reqBytes, 0, reqBytes.Length, SocketFlags.None); while(sent != reqBytes.Length) { sent += s.Send(reqBytes, sent, reqBytes.Length - sent, SocketFlags.None); } } catch (Exception e) { Console.WriteLine("Exception occurred while sending: " + e.ToString()); return; } // receive the reply Console.WriteLine("HTTP Server reply:\r\n------------------"); try { byte[] buffer = new byte[4096]; int ret = s.Receive(buffer); while(ret != 0) { Console.Write(Encoding.ASCII.GetString(buffer, 0, ret)); ret = s.Receive(buffer); } } catch (Exception e) { Console.WriteLine("Exception occurred while receiving: " + e.ToString()); return; } try { s.Shutdown(SocketShutdown.Both); // shut down the TCP connection } catch (Exception e) { Console.WriteLine("Exception occurred while shutting the connection down: " + e.ToString()); return; } s.Close(); }