connectsocket.cpp

It can also accept a number of ftp connection (multithreaded), and with most of the commercial ftp s

		// found command ?
		if (strCommand == commandList[nCommand].m_pszName)
		{
			// did we expect an argument ?
			if (commandList[nCommand].m_bHasArguments && (strArguments == ""))
			{
				SendResponse("501 Syntax error");
				return;
			}
			break;			
		}
	}

	if (nCommand == TOK_ERROR)
	{
		// command is not in our list
		SendResponse("500 Syntax error, command unrecognized.");
		return;
	}
	
	// no commands are excepted before successfull logged on
	if (nCommand > TOK_PASS && !m_bLoggedon)
	{
		SendResponse("530 Please log in with USER and PASS first.");
		return;
	}

	// proces command
	switch(nCommand)
	{
		// specify username
		case TOK_USER:
		{
			strArguments.MakeLower();
			m_bLoggedon = FALSE;
			m_strUserName = strArguments;

			CString strPeerAddress;
			UINT nPeerPort;
			GetPeerName(strPeerAddress, nPeerPort);

			// tell FTP server a new user has connected
			CConnectThread *pThread = (CConnectThread *)m_pThread;
			((CFTPServer *)pThread->m_pWndServer)->m_pEventSink->OnFTPUserConnected(m_pThread->m_nThreadID, m_strUserName, strPeerAddress);

			SendResponse("331 Password required for " + strArguments);
		}
		break;

		// specify password
		case TOK_PASS:
		{
			// already logged on ?
			if (m_bLoggedon)
			{
				SendResponse("503 Bad sequence of commands.");
			}
			else
			{
				// check user and password
				CUser user;
				if (theServer.m_UserManager.CheckUser(m_strUserName, strArguments, user))
				{
					// set home directory of user
					m_strCurrentDir = "/";

					// succesfully logged on
					m_bLoggedon = TRUE;
					SendResponse("230 Logged on");
				}
				else 
					SendResponse("530 Login or password incorrect!");
			}
		}
		break;
		
		// change current directory
		case TOK_CWD:
		{
			int nResult = theServer.m_UserManager.ChangeDirectory(m_strUserName, m_strCurrentDir, strArguments);
			
			CString str;
			switch(nResult)
			{
				case 0:
					str.Format("250 CWD successful. \"%s\" is current directory.", m_strCurrentDir);
					SendResponse(str);
					break;
				case 1:
					str.Format("550 CWD failed. \"%s\": Permission denied.", strArguments);
					SendResponse(str);
					break;
				default:
					str.Format("550 CWD failed. \"%s\": directory not found.", strArguments);
					SendResponse(str);
					break;
			}
		}
		break; 

		// print current directory
		case TOK_PWD:
		{
			CString str;
			str.Format("257 \"%s\" is current directory.", m_strCurrentDir);
			SendResponse(str);	
		}
		break;

		// specify IP and port (PORT a1,a2,a3,a4,p1,p2) -> IP address a1.a2.a3.a4, port p1*256+p2. 
		case TOK_PORT:
		{
			CString strSub;
			int nCount=0;

			while (AfxExtractSubString(strSub, strArguments, nCount++, ','))
			{
				switch(nCount)
				{
					case 1:	// a1
						m_TransferStatus.m_strRemoteHost = strSub;
						m_TransferStatus.m_strRemoteHost += ".";
						break;
					case 2:	// a2
						m_TransferStatus.m_strRemoteHost += strSub;
						m_TransferStatus.m_strRemoteHost += ".";
						break;
					case 3:	// a3
						m_TransferStatus.m_strRemoteHost += strSub;
						m_TransferStatus.m_strRemoteHost += ".";
						break;
					case 4:	// a4
						m_TransferStatus.m_strRemoteHost += strSub;
						break;
					case 5:	// p1
						m_TransferStatus.m_nRemotePort = 256*atoi(strSub);
						break;
					case 6:	// p2
						m_TransferStatus.m_nRemotePort += atoi(strSub);
						break;
				}
			}
			m_TransferStatus.m_bPassiveMode = FALSE;
			SendResponse("200 Port command successful");
			break;
		}
		
		// switch to passive mode
		case TOK_PASV:
		{
			// delete existing datasocket
			DestroyDataSocket();

			// create new data socket
			m_TransferStatus.m_pDataSocket = new CDataSocket(this, -1);

			if (!m_TransferStatus.m_pDataSocket->Create())
			{
				DestroyDataSocket();				
				SendResponse("421 Can't create socket");
				break;
			}
			// start listening
			m_TransferStatus.m_pDataSocket->Listen();
			m_TransferStatus.m_pDataSocket->AsyncSelect();
			
			CString strIP, strTmp;
			UINT nPort;
			
			// get our ip address
			GetSockName(strIP, nPort);
			// Now retrieve the port
			m_TransferStatus.m_pDataSocket->GetSockName(strTmp, nPort);
			// Reformat the ip
			strIP.Replace(".",",");
			// tell the client which address/port to connect to
			CString str;
			str.Format("227 Entering Passive Mode (%s,%d,%d)", strIP, nPort/256, nPort%256);
			SendResponse(str);
			m_TransferStatus.m_bPassiveMode = TRUE;
			break;
		} 

		case TOK_TYPE:
		{
			SendResponse("200 Type set to " + strArguments);
		}
		break;

		// list current directory
		case TOK_LIST:
		{
			if(!m_TransferStatus.m_bPassiveMode && (m_TransferStatus.m_strRemoteHost == "" || m_TransferStatus.m_nRemotePort == -1))
			{
				SendResponse("503 Bad sequence of commands.");
			}
			else
			{
				// if client did not specify a directory use current dir
				if (strArguments == "")
				{
					strArguments = m_strCurrentDir;
				}
				else
				{
					// check if argument is file or directory
					CString strResult;
					int nResult = theServer.m_UserManager.GetFileName(m_strUserName, strArguments, m_strCurrentDir, FTP_LIST, strResult);
					if (nResult == 0)
					{
						strArguments = strResult;
					}
				}
				CString strListing;
				int nResult = theServer.m_UserManager.GetDirectoryList(m_strUserName, strArguments, strListing);
				switch(nResult)
				{
					case 1:
						SendResponse("550 Permission denied");
						break;
					case 2:
						SendResponse("550 Directory not found");
						break;
					default:
						if (!m_TransferStatus.m_bPassiveMode)
						{
							CDataSocket *pDataSocket = new CDataSocket(this, 0);
							pDataSocket->Create();
							pDataSocket->SetData(strListing);
							pDataSocket->AsyncSelect();
							m_TransferStatus.m_pDataSocket = pDataSocket;
							if (!pDataSocket->Connect(m_TransferStatus.m_strRemoteHost, m_TransferStatus.m_nRemotePort))
							{
								if (GetLastError() != WSAEWOULDBLOCK)
								{
									SendResponse("425 Can't open data connection");
									break;
								}
							}
							SendResponse("150 Opening data channel for directory list."); 
						}
						else
						{
							m_TransferStatus.m_pDataSocket->SetData(strListing);
							m_TransferStatus.m_pDataSocket->SetTransferType(0);
						}
						break;
				}
			} 
			break;
		} 
		// change to parent directory
		case TOK_CDUP:
		{
			CString strDirectory = "..";
			CString str;
			int nResult = theServer.m_UserManager.ChangeDirectory(m_strUserName, m_strCurrentDir, strDirectory);
			switch(nResult)
			{
				case 0:
					str.Format("250 CWD successful. \"%s\" is current directory.", m_strCurrentDir);
					SendResponse(str);
					break;
				case 1:
					str.Format("550 CWD failed. \"%s\": Permission denied.", strDirectory);
					SendResponse(str);
					break;
				case 2:
					str.Format("550 CWD failed. \"%s\": directory not found.", strDirectory);
					SendResponse(str);
					break;
			}
		}
		break; 

		// retrieve file
		case TOK_RETR:
		{
			if(!m_TransferStatus.m_bPassiveMode && (m_TransferStatus.m_strRemoteHost == "" || m_TransferStatus.m_nRemotePort == -1))
			{
				SendResponse("503 Bad sequence of commands.");
				break;
			}
			
			CString strResult;
			int nResult = theServer.m_UserManager.GetFileName(m_strUserName, strArguments, m_strCurrentDir, FTP_DOWNLOAD, strResult);
			switch(nResult)
			{
				case 1:
					SendResponse("550 Permission denied");
					break;
				case 2:
					SendResponse("550 File not found");
					break;
				default:
					if (!m_TransferStatus.m_bPassiveMode)
					{
						CDataSocket *pDataSocket = new CDataSocket(this, 1);
						m_TransferStatus.m_pDataSocket = pDataSocket;
						pDataSocket->Create();
						pDataSocket->AsyncSelect();
						pDataSocket->SetData(strResult);
						if (pDataSocket->Connect(m_TransferStatus.m_strRemoteHost ,m_TransferStatus.m_nRemotePort) == 0)
						{
							if (GetLastError() != WSAEWOULDBLOCK)
							{
								SendResponse("425 Can't open data connection");
								break;
							}
						}
						SendResponse("150 Opening data channel for file transfer.");
					}
					else
					{
						m_TransferStatus.m_pDataSocket->SetData(strResult);
						m_TransferStatus.m_pDataSocket->SetTransferType(1);
					}
					break;
			}
			break;	
		}

		// client wants to upload file
		case TOK_STOR:
		{
			if(m_TransferStatus.m_bPassiveMode == -1)
			{
				SendResponse("503 Bad sequence of commands.");
				break;
			}
			if(!m_TransferStatus.m_bPassiveMode && (m_TransferStatus.m_strRemoteHost == "" || m_TransferStatus.m_nRemotePort == -1))
			{
				SendResponse("503 Bad sequence of commands.");
				break;
			}
			
			CString strResult;
			int nResult = theServer.m_UserManager.GetFileName(m_strUserName, strArguments, m_strCurrentDir, FTP_UPLOAD, strResult);
			switch(nResult)
			{
				case 1:
					SendResponse("550 Permission denied");
					break;
				case 2:
					SendResponse("550 Filename invalid");
					break;
				default:
					if (!m_TransferStatus.m_bPassiveMode)
					{
						CDataSocket *pDataSocket = new CDataSocket(this, 2);
						m_TransferStatus.m_pDataSocket = pDataSocket;
						pDataSocket->Create();
						pDataSocket->AsyncSelect();
						pDataSocket->SetData(strResult);

						if (pDataSocket->Connect(m_TransferStatus.m_strRemoteHost, m_TransferStatus.m_nRemotePort) == 0)
						{
							if (GetLastError() != WSAEWOULDBLOCK)
							{
								SendResponse("425 Can't open data connection");
								break;
							}
						}
						SendResponse("150 Opening data channel for file transfer.");
					}
					else
					{
						m_TransferStatus.m_pDataSocket->SetData(strResult);
						m_TransferStatus.m_pDataSocket->SetTransferType(2);
					}
					break;
			}
		}
		break;
		
		// get file size
		case TOK_SIZE:
		{
			CString strResult;
			int nResult = theServer.m_UserManager.GetFileName(m_strUserName, strArguments, m_strCurrentDir, FTP_DOWNLOAD, strResult);