public void TestExcessiveDataInIMAPConversation() { var sb = new StringBuilder(); for (int i = 0; i < 100000; i++) { sb.Append("1234567890"); } sb.Append(".com\r\n"); string command = "A03 NOOP " + sb; var socket = new TcpConnection(); CustomAssert.IsTrue(socket.Connect(143)); socket.Receive(); socket.Send(command); try { string response = socket.Receive(); CustomAssert.IsTrue(response.StartsWith("* BYE")); } catch (System.IO.IOException ex) { AssertIsConnectionTerminatedException(ex); } socket.Disconnect(); }
public void Send100MBMessage() { long memoryUsage = Shared.GetCurrentMemoryUsage(); _application.Settings.MaxMessageSize = 0; TcpConnection socket = new TcpConnection(); socket.Connect(25); socket.Receive(); socket.Send("HELO test.com\r\n"); socket.Receive(); // Build a large string... StringBuilder sb = new StringBuilder(); sb.Append("A01"); for (int i = 0; i < 10000; i++) { sb.Append("01234567890012345678900123456789001234567890012345678900123456789001234567890012345678900123456789001234567890\r\n"); } int length = sb.Length; sb.Append(Environment.NewLine); socket.Send("MAIL FROM: [email protected]\r\n"); socket.Receive(); socket.Send("RCPT TO: [email protected]\r\n"); socket.Receive(); socket.Send("DATA\r\n"); socket.Receive(); for (int i = 1; i <= 100; i++) { Shared.AssertLowMemoryUsage(memoryUsage + 30); try { socket.Send(sb.ToString()); } catch (Exception) { return; } if ((i % 10) == 0) { TestTracer.WriteTraceInfo("{0}/{1}", i, 1000); } } socket.Send("\r\n.\r\n"); string result = socket.Receive(); Assert.IsTrue(result.StartsWith("250")); socket.Send("QUIT\r\n"); result = socket.Receive(); socket.Disconnect(); Pop3ClientSimulator.AssertMessageCount(_domain.Accounts[0].Address, "test", 1); }
public void AuthShouldUpdateLastLogonTime() { Account account = SingletonProvider<TestSetup>.Instance.AddAccount(_domain, "*****@*****.**", "test"); DateTime lastLogonTimeBefore = Convert.ToDateTime(account.LastLogonTime); Thread.Sleep(1000); var sock = new TcpConnection(); sock.Connect(25); CustomAssert.IsTrue(sock.Receive().StartsWith("220")); sock.Send("EHLO test.com\r\n"); CustomAssert.IsTrue(sock.Receive().StartsWith("250")); string base64EncodedUsername = EncodeBase64("*****@*****.**"); sock.Send("AUTH LOGIN " + base64EncodedUsername + "\r\n"); CustomAssert.IsTrue(sock.Receive().StartsWith("334")); sock.Send(EncodeBase64("test") + "\r\n"); CustomAssert.IsTrue(sock.Receive().StartsWith("235")); DateTime lastLogonTimeAfter = Convert.ToDateTime(SingletonProvider<TestSetup>.Instance.GetApp().Domains[0].Accounts[0].LastLogonTime); CustomAssert.AreNotEqual(lastLogonTimeBefore, lastLogonTimeAfter); }
public void TestLongLineInPOP3Conversation() { var sb = new StringBuilder(); for (int i = 0; i < 400; i++) { sb.Append("1234567890"); } sb.Append(".com"); string command = "NOOP " + sb; var socket = new TcpConnection(); Assert.IsTrue(socket.Connect(110)); socket.Receive(); socket.Send(command + "\r\n"); string response = socket.Receive(); Assert.IsTrue(response.StartsWith("-ERR Line too long.")); socket.Disconnect(); }
public void TestTooManyInvalidCommandsAUTH() { Application application = SingletonProvider<TestSetup>.Instance.GetApp(); Settings settings = _settings; settings.DisconnectInvalidClients = true; settings.MaxNumberOfInvalidCommands = 3; var sim = new TcpConnection(); sim.Connect(25); sim.Send("EHLO test.com\r\n"); for (int i = 1; i <= 6; i++) { try { sim.Send("AUTH LOGIN\r\n"); string result = sim.Receive(); if (result.Contains("Too many invalid commands")) return; if (i > 5) break; sim.Send("YWNhZGVtaWE=\r\n"); sim.Receive(); sim.Send("abc\r\n"); sim.Receive(); } catch (Exception) { if (i < 5) { CustomAssert.Fail("Was disconnected prematurely."); } return; } } CustomAssert.Fail("Wasn't disconnected"); }
public void TestRcptToSyntax() { Account account1 = SingletonProvider<TestSetup>.Instance.AddAccount(_domain, "*****@*****.**", "test"); var oSMTP = new TcpConnection(); oSMTP.Connect(25); CustomAssert.IsTrue(oSMTP.Receive().StartsWith("220")); oSMTP.Send("HELO test\r\n"); CustomAssert.IsTrue(oSMTP.Receive().StartsWith("250")); // A few tests of invalid syntax. CustomAssert.IsTrue(oSMTP.SendAndReceive("MAIL FROM: <*****@*****.**>\r\n").StartsWith("250")); CustomAssert.IsFalse(oSMTP.SendAndReceive("RCPT TO: [email protected]>\r\n").StartsWith("250")); CustomAssert.IsFalse(oSMTP.SendAndReceive("RCPT TO: <[email protected]\r\n").StartsWith("250")); CustomAssert.IsFalse(oSMTP.SendAndReceive("RCPT TO <[email protected]\r\n").StartsWith("250")); CustomAssert.IsFalse(oSMTP.SendAndReceive("RCPT TO<[email protected]\r\n").StartsWith("250")); CustomAssert.IsTrue(oSMTP.SendAndReceive("RCPT TO: <*****@*****.**>\r\n").StartsWith("250")); CustomAssert.IsTrue(oSMTP.SendAndReceive("RCPT TO: [email protected]\r\n").StartsWith("250")); oSMTP.Disconnect(); }
public void TestHelo() { var oSimulator = new TcpConnection(); oSimulator.Connect(25); string sWelcome = oSimulator.Receive(); oSimulator.Send("HELO\r\n"); string sResponse = oSimulator.Receive(); if (!sResponse.StartsWith("501")) throw new Exception("Invalid response to HELO"); oSimulator.Send("HELO \r\n"); sResponse = oSimulator.Receive(); if (!sResponse.StartsWith("501")) throw new Exception("Invalid response to HELO"); oSimulator.Send("HELO TEST.COM\r\n"); sResponse = oSimulator.Receive(); if (!sResponse.StartsWith("250")) throw new Exception("Invalid response to HELO"); oSimulator.Send("HELO TEST.COM\r\n"); sResponse = oSimulator.Receive(); if (!sResponse.StartsWith("250")) throw new Exception("Invalid response to HELO"); oSimulator.Send("EHLO TEST.COM\r\n"); sResponse = oSimulator.Receive(); if (!sResponse.StartsWith("250")) throw new Exception("Invalid response to HELO"); oSimulator.Send("EHLO TEST.COM\r\n"); sResponse = oSimulator.Receive(); if (!sResponse.StartsWith("250")) throw new Exception("Invalid response to HELO"); oSimulator.Disconnect(); }
public void TestSMTPServerAuthLoginUsernameAsThirdParameter() { _settings.AllowSMTPAuthPlain = true; var sock = new TcpConnection(); sock.Connect(25); CustomAssert.IsTrue(sock.Receive().StartsWith("220")); sock.Send("EHLO test.com\r\n"); CustomAssert.IsTrue(sock.Receive().StartsWith("250")); string base64EncodedUsername = EncodeBase64(GetUsername()); sock.Send("AUTH LOGIN " + base64EncodedUsername + "\r\n"); CustomAssert.IsTrue(sock.Receive().StartsWith("334")); sock.Send(EncodeBase64(GetPassword()) + "\r\n"); CustomAssert.IsTrue(sock.Receive().StartsWith("535")); EnsureNoPassword(); }
public void TestPOP3DownloadOfLargeMessage() { Send100MBMessage(); Pop3ClientSimulator.AssertMessageCount("*****@*****.**", "test", 1); TcpConnection socket = new TcpConnection(); socket.Connect(110); // Receive welcome message. socket.Receive(); socket.Send("USER " + "*****@*****.**" + "\r\n"); socket.ReadUntil("+OK"); socket.Send("PASS " + "test" + "\r\n"); socket.ReadUntil("+OK"); socket.Send("RETR 1\r\n"); var endOfResponseSB = new StringBuilder(); string endOfResponse = ""; while (endOfResponse.IndexOf("\r\n.\r\n") < 0) { if (endOfResponse.IndexOf("-ERR no such message") >= 0) { socket.Disconnect(); Assert.Fail("Nope"); } endOfResponseSB.Append(socket.Receive()); if (endOfResponseSB.Length > 100) endOfResponseSB.Remove(0, endOfResponseSB.Length - 100); endOfResponse = endOfResponseSB.ToString(); } socket.Send("DELE 1\r\n"); socket.ReadUntil("+OK"); socket.Send("QUIT\r\n"); socket.ReadUntil("+OK"); socket.Disconnect(); }
public void TestLongSMTPDataSessionWithoutNewline() { long memoryUsage = Shared.GetCurrentMemoryUsage(); var socket = new TcpConnection(); socket.Connect(25); socket.Receive(); socket.Send("HELO test.com\r\n"); socket.Receive(); // Build a large string... var sb = new StringBuilder(); sb.Append("A01"); for (int i = 0; i < 10000; i++) { sb.Append("01234567890012345678900123456789001234567890012345678900123456789001234567890012345678900123456789001234567890"); } socket.Send("MAIL FROM: [email protected]\r\n"); socket.Receive(); socket.Send("RCPT TO: [email protected]\r\n"); socket.Receive(); socket.Send("DATA\r\n"); socket.Receive(); for (int i = 1; i <= 1000; i++) { Shared.AssertLowMemoryUsage(memoryUsage + 30); try { socket.Send(sb.ToString()); } catch (Exception) { return; } if ((i%10) == 0) { TestTracer.WriteTraceInfo("{0}/{1}", i, 1000); } } socket.Send("\r\n.\r\n"); string result = socket.Receive(); Assert.IsTrue(result.StartsWith("554 Too long line was received. Transmission aborted.")); socket.Send("QUIT\r\n"); socket.Receive(); socket.Disconnect(); }
public void TestLongSMTPDataSessionIncludingNewline() { long memoryUsage = Shared.GetCurrentMemoryUsage(); _application.Settings.MaxMessageSize = 0; var socket = new TcpConnection(); socket.Connect(25); socket.Receive(); socket.Send("HELO test.com\r\n"); socket.Receive(); // Build a large string... var sb = new StringBuilder(); sb.Append("A01"); for (int i = 0; i < 10000; i++) { sb.Append("01234567890012345678900123456789001234567890012345678900123456789001234567890012345678900123456789001234567890\r\n"); } sb.Append(Environment.NewLine); socket.Send("MAIL FROM: [email protected]\r\n"); socket.Receive(); socket.Send("RCPT TO: [email protected]\r\n"); socket.Receive(); socket.Send("DATA\r\n"); socket.Receive(); for (int i = 0; i < 100; i++) { Shared.AssertLowMemoryUsage(memoryUsage + 30); try { socket.Send(sb.ToString()); } catch (Exception) { return; } } socket.Send("\r\n.\r\n"); string result = socket.Receive(); Assert.IsTrue(result.StartsWith("250")); socket.Send("QUIT\r\n"); socket.Receive(); socket.Disconnect(); POP3ClientSimulator.AssertMessageCount(_domain.Accounts[0].Address, "test", 1); }
public bool Logout() { _tcpConnection.Send("A99 LOGOUT\r\n"); string sData = _tcpConnection.Receive(); if (sData.StartsWith("*")) { return(true); } else { return(false); } }
public void TestExcessiveDataInPOP3Conversation() { var sb = new StringBuilder(); for (int i = 0; i < 100000; i++) { sb.Append("1234567890"); } string command = "HELP " + sb; var socket = new TcpConnection(); CustomAssert.IsTrue(socket.Connect(110)); socket.Receive(); socket.Send(command + "\r\n"); try { string response = socket.Receive(); CustomAssert.IsTrue(response.StartsWith("-ERR")); socket.Disconnect(); } catch (IOException ex) { AssertIsConnectionTerminatedException(ex); } }
public void TestLongLineInSMTPConversation() { var sb = new StringBuilder(); for (int i = 0; i < 400; i++) { sb.Append("1234567890"); } sb.Append(".com"); string command = "HELO " + sb; var socket = new TcpConnection(); CustomAssert.IsTrue(socket.Connect(25)); socket.Receive(); socket.Send(command + "\r\n"); string response = socket.Receive(); CustomAssert.IsTrue(response.StartsWith("500")); socket.Disconnect(); }
public string SendAndReceive(string sData) { _tcpConnection.Send(sData); return(Receive()); }
public void TestSendToTooManyRecipients() { hMailServer.Accounts accounts = _domain.Accounts; SingletonProvider<TestSetup>.Instance.AddAccount(accounts, string.Format("*****@*****.**"), "test"); var sock = new TcpConnection(); sock.Connect(25); sock.ReadUntil("\r\n"); string result; sock.Send("EHLO test.com\r\n"); result = sock.ReadUntil("\r\n"); Assert.IsTrue(result.StartsWith("250")); sock.Send("MAIL FROM: [email protected]\r\n"); result = sock.ReadUntil("\r\n"); Assert.IsTrue(result.StartsWith("250")); const int recipientCount = 51000; for (int i = 1; i <= recipientCount; i++) { string address = string.Format("test{0}@gmail.com", i); sock.Send(string.Format("RCPT TO: <{0}>\r\n", address)); result = sock.ReadUntil("\r\n"); if (i <= 50000) { Assert.IsTrue(result.StartsWith("250")); } else { Assert.IsFalse(result.StartsWith("250")); } if (i % 100 == 0) { TestTracer.WriteTraceInfo("{0}/{1}", i, recipientCount); } } }
public void TestLongSMTPCommand() { var socket = new TcpConnection(); socket.Connect(25); // Build a large string... var sb = new StringBuilder(); sb.Append("A01"); for (int i = 0; i < 1000000; i++) { sb.Append("01234567890"); } sb.Append(Environment.NewLine); for (int i = 0; i < 100; i++) { try { socket.Send(sb.ToString()); } catch (Exception) { return; } if ((i % 10) == 0) { TestTracer.WriteTraceInfo("{0}/{1}", i, 100); } } socket.Send("\r\n"); socket.Receive(); socket.Disconnect(); }
private void AssertValidMailRcptToCommand(string comamnd) { var smtpClientSimulator = new TcpConnection(); smtpClientSimulator.Connect(25); Assert.IsTrue(smtpClientSimulator.Receive().StartsWith("220")); smtpClientSimulator.Send("HELO test\r\n"); Assert.IsTrue(smtpClientSimulator.Receive().StartsWith("250")); smtpClientSimulator.Send("MAIL FROM: <*****@*****.**>\r\n"); Assert.IsTrue(smtpClientSimulator.Receive().StartsWith("250")); string result = smtpClientSimulator.SendAndReceive(comamnd + "\r\n"); smtpClientSimulator.Disconnect(); Assert.AreEqual("250 OK\r\n", result); }
private void AssertInvalidMailFromCommand(string command, string expectedResponse) { var smtpClientSimulator = new TcpConnection(); smtpClientSimulator.Connect(25); Assert.IsTrue(smtpClientSimulator.Receive().StartsWith("220")); smtpClientSimulator.Send("HELO test\r\n"); Assert.IsTrue(smtpClientSimulator.Receive().StartsWith("250")); string result = smtpClientSimulator.SendAndReceive(command+ "\r\n"); smtpClientSimulator.Disconnect(); Assert.AreEqual(expectedResponse + "\r\n", result); }
public void TestSMTPServerAuthPlain() { _settings.AllowSMTPAuthPlain = true; var sock = new TcpConnection(); sock.Connect(25); CustomAssert.IsTrue(sock.Receive().StartsWith("220")); sock.Send("EHLO test.com\r\n"); CustomAssert.IsTrue(sock.Receive().StartsWith("250")); sock.Send("AUTH PLAIN\r\n"); CustomAssert.IsTrue(sock.Receive().StartsWith("334")); string str = "\t" + GetUsername() + "\t" + GetPassword(); sock.Send(EncodeBase64(str) + "\r\n"); CustomAssert.IsTrue(sock.Receive().StartsWith("535")); EnsureNoPassword(); }
public bool ConnectAndLogon(string username, string password, out string errorMessage) { errorMessage = ""; if (!Connect()) { return(false); } if (!ReceiveBanner(out errorMessage)) { return(false); } _tcpConnection.Send("USER " + username + "\r\n"); errorMessage = _tcpConnection.ReadUntil("+OK Send your password"); if (!errorMessage.StartsWith("+OK")) { return(false); } _tcpConnection.Send("PASS " + password + "\r\n"); errorMessage = _tcpConnection.ReadUntil(new List <string> { "+OK", "-ERR" }); return(errorMessage.StartsWith("+OK")); }
public void TestEHLOKeywords() { Application application = SingletonProvider<TestSetup>.Instance.GetApp(); Settings settings = _settings; settings.HostName = "examplify.com"; var socket = new TcpConnection(); CustomAssert.IsTrue(socket.Connect(25)); string result = socket.Receive(); socket.Send("EHLO example.com\r\n"); result = socket.Receive(); socket.Disconnect(); CustomAssert.IsTrue(result.Contains("250-" + settings.HostName)); }
public void Send(string s) { _conversation += s; _tcpConnection.Send(s); }
public void TestMailFromSyntaxValidation() { Account account1 = SingletonProvider<TestSetup>.Instance.AddAccount(_domain, "*****@*****.**", "test"); var oSMTP = new TcpConnection(); oSMTP.Connect(25); CustomAssert.IsTrue(oSMTP.Receive().StartsWith("220")); oSMTP.Send("HELO test\r\n"); CustomAssert.IsTrue(oSMTP.Receive().StartsWith("250")); // A few tests of invalid syntax. CustomAssert.IsFalse(oSMTP.SendAndReceive("MAIL FROM: <[email protected]\r\n").StartsWith("250")); CustomAssert.IsFalse(oSMTP.SendAndReceive("MAIL FROM: [email protected]>\r\n").StartsWith("250")); CustomAssert.IsFalse(oSMTP.SendAndReceive("MAIL FROM: < [email protected] \r\n").StartsWith("250")); CustomAssert.IsFalse(oSMTP.SendAndReceive("MAIL FROM: < \r\n").StartsWith("250")); CustomAssert.IsFalse(oSMTP.SendAndReceive("MAIL FROM: > \r\n").StartsWith("250")); CustomAssert.IsFalse(oSMTP.SendAndReceive("MAIL FROM: <[email protected]\r\n").StartsWith("250")); CustomAssert.IsFalse(oSMTP.SendAndReceive("MAIL FROM <*****@*****.**>\r\n").StartsWith("250")); CustomAssert.IsFalse(oSMTP.SendAndReceive("MAIL FROM [email protected]\r\n").StartsWith("250")); // Valid syntax, < and > CustomAssert.IsTrue(oSMTP.SendAndReceive("MAIL FROM: <*****@*****.**>\r\n").StartsWith("250")); CustomAssert.IsTrue(oSMTP.SendAndReceive("RSET\r\n").StartsWith("250")); CustomAssert.IsTrue(oSMTP.SendAndReceive("MAIL FROM: [email protected]\r\n").StartsWith("250")); CustomAssert.IsTrue(oSMTP.SendAndReceive("RSET\r\n").StartsWith("250")); CustomAssert.IsTrue(oSMTP.SendAndReceive("MAIL FROM: [email protected] \r\n").StartsWith("250")); CustomAssert.IsTrue(oSMTP.SendAndReceive("RSET\r\n").StartsWith("250")); CustomAssert.IsTrue(oSMTP.SendAndReceive("MAIL FROM:[email protected]\r\n").StartsWith("250")); CustomAssert.IsTrue(oSMTP.SendAndReceive("RSET\r\n").StartsWith("250")); CustomAssert.IsTrue(oSMTP.SendAndReceive("MAIL FROM:<*****@*****.**>\r\n").StartsWith("250")); CustomAssert.IsTrue(oSMTP.SendAndReceive("RSET\r\n").StartsWith("250")); oSMTP.Disconnect(); }
public void MailFromWithAuthParameterShouldBeAccepted() { Account account1 = SingletonProvider<TestSetup>.Instance.AddAccount(_domain, "*****@*****.**", "test"); var smtpClientSimulator = new TcpConnection(); smtpClientSimulator.Connect(25); Assert.IsTrue(smtpClientSimulator.Receive().StartsWith("220")); smtpClientSimulator.Send("HELO test\r\n"); Assert.IsTrue(smtpClientSimulator.Receive().StartsWith("250")); // A few tests of invalid syntax. Assert.IsTrue(smtpClientSimulator.SendAndReceive("MAIL FROM: <*****@*****.**> AUTH=<>\r\n").StartsWith("250")); smtpClientSimulator.Disconnect(); }
public void TestSameRecipientMultipleTimes() { Logging logging = SingletonProvider<TestSetup>.Instance.GetApp().Settings.Logging; logging.AWStatsEnabled = true; logging.Enabled = true; if (File.Exists(logging.CurrentAwstatsLog)) File.Delete(logging.CurrentAwstatsLog); Account account1 = SingletonProvider<TestSetup>.Instance.AddAccount(_domain, "*****@*****.**", "test"); var oSMTP = new TcpConnection(); oSMTP.Connect(25); CustomAssert.IsTrue(oSMTP.Receive().StartsWith("220")); oSMTP.Send("HELO test\r\n"); CustomAssert.IsTrue(oSMTP.Receive().StartsWith("250")); oSMTP.Send("MAIL FROM: [email protected]\r\n"); CustomAssert.IsTrue(oSMTP.Receive().StartsWith("250")); oSMTP.Send("RCPT TO: [email protected]\r\n"); CustomAssert.IsTrue(oSMTP.Receive().StartsWith("250")); oSMTP.Send("RCPT TO: [email protected]\r\n"); CustomAssert.IsTrue(oSMTP.Receive().StartsWith("250")); oSMTP.Disconnect(); }
public void TestRcptToSyntax() { SingletonProvider<TestSetup>.Instance.AddAccount(_domain, "*****@*****.**", "test"); var smtpClientSimulator = new TcpConnection(); smtpClientSimulator.Connect(25); Assert.IsTrue(smtpClientSimulator.Receive().StartsWith("220")); smtpClientSimulator.Send("HELO test\r\n"); Assert.IsTrue(smtpClientSimulator.Receive().StartsWith("250")); // A few tests of invalid syntax. Assert.IsTrue(smtpClientSimulator.SendAndReceive("MAIL FROM: <*****@*****.**>\r\n").StartsWith("250")); Assert.IsFalse(smtpClientSimulator.SendAndReceive("RCPT TO: [email protected]>\r\n").StartsWith("250")); Assert.IsFalse(smtpClientSimulator.SendAndReceive("RCPT TO: <[email protected]\r\n").StartsWith("250")); Assert.IsFalse(smtpClientSimulator.SendAndReceive("RCPT TO <[email protected]\r\n").StartsWith("250")); Assert.IsFalse(smtpClientSimulator.SendAndReceive("RCPT TO<[email protected]\r\n").StartsWith("250")); Assert.IsTrue(smtpClientSimulator.SendAndReceive("RCPT TO: <*****@*****.**>\r\n").StartsWith("250")); Assert.IsTrue(smtpClientSimulator.SendAndReceive("RCPT TO: [email protected]\r\n").StartsWith("250")); smtpClientSimulator.Disconnect(); }
public void TestTooManyInvalidCommandsTempError() { Account account = SingletonProvider<TestSetup>.Instance.AddAccount(_domain, "*****@*****.**", "test"); for (int i = 0; i < 10; i++) SingletonProvider<TestSetup>.Instance.AddAccount(_domain, string.Format("test{0}@test.com", i), "test"); Application application = SingletonProvider<TestSetup>.Instance.GetApp(); Settings settings = _settings; settings.DisconnectInvalidClients = true; settings.MaxNumberOfInvalidCommands = 5; settings.AntiSpam.GreyListingEnabled = true; var sim = new TcpConnection(); sim.Connect(25); string res = sim.Receive(); sim.Send("EHLO test.com\r\n"); res = sim.Receive(); sim.Send("MAIL FROM: <*****@*****.**>\r\n"); res = sim.Receive(); for (int i = 1; i < 10; i++) { string address = string.Format("test{0}@test.com", i); sim.Send("RCPT TO: " + address + "\r\n"); res = sim.Receive(); CustomAssert.AreEqual("451 Please try again later.\r\n", res); } sim.Disconnect(); }
private static void TriggerCrashSimulationError() { using (var tcpConnection = new TcpConnection()) { tcpConnection.Connect(25); tcpConnection.Send("help\r\n"); tcpConnection.Receive(); } }