FTP服务器 C#

时间:2021-03-30 03:26:45
【文件属性】:

文件名称:FTP服务器 C#

文件大小:91KB

文件格式:ZIP

更新时间:2021-03-30 03:26:45

FTP服务器 C#

用VS编写的FTP服务器软件,C#网络程序编程学习用。 代码: using System; using System.Collections.Generic; using System.Globalization; using System.IO; using System.Net; using System.Net.Sockets; using System.Threading; using System.Windows.Forms; namespace FtpServer { public partial class FtpServerForm : Form { TcpListener myTcpListener = null; private Thread listenThread; // 保存用户名和密码 Dictionary users; public FtpServerForm() { InitializeComponent(); // 初始化用户名和密码 users = new Dictionary(); users.Add("admin", "admin"); // 设置默认的主目录 tbxFtpRoot.Text = "F:/MyFtpServerRoot/"; IPAddress[] ips = Dns.GetHostAddresses(""); tbxFtpServerIp.Text = ips[5].ToString(); tbxFtpServerPort.Text = "21"; lstboxStatus.Enabled = false; } // 启动服务器 private void btnFtpServerStartStop_Click(object sender, EventArgs e) { if (myTcpListener == null) { listenThread = new Thread(ListenClientConnect); listenThread.IsBackground = true; listenThread.Start(); lstboxStatus.Enabled = true; lstboxStatus.Items.Clear(); lstboxStatus.Items.Add("已经启动Ftp服务..."); btnFtpServerStartStop.Text = "停止"; } else { myTcpListener.Stop(); myTcpListener = null; listenThread.Abort(); lstboxStatus.Items.Add("Ftp服务已停止!"); lstboxStatus.TopIndex = lstboxStatus.Items.Count - 1; btnFtpServerStartStop.Text = "启动"; } } // 监听端口,处理客户端连接 private void ListenClientConnect() { myTcpListener = new TcpListener(IPAddress.Parse(tbxFtpServerIp.Text), int.Parse(tbxFtpServerPort.Text)); // 开始监听传入的请求 myTcpListener.Start(); AddInfo("启动FTP服务成功!"); AddInfo("Ftp服务器运行中...[点击”停止“按钮停止FTP服务]"); while (true) { try { // 接收连接请求 TcpClient tcpClient = myTcpListener.AcceptTcpClient(); AddInfo(string.Format("客户端({0})与本机({1})建立Ftp连接", tcpClient.Client.RemoteEndPoint, myTcpListener.LocalEndpoint)); User user = new User(); user.commandSession = new UserSeesion(tcpClient); user.workDir = tbxFtpRoot.Text; Thread t = new Thread(UserProcessing); t.IsBackground = true; t.Start(user); } catch { break; } } } // 处理客户端用户请求 private void UserProcessing(object obj) { User user = (User)obj; string sendString = "220 FTP Server v1.0"; RepleyCommandToUser(user, sendString); while (true) { string receiveString = null; try { // 读取客户端发来的请求信息 receiveString = user.commandSession.streamReader.ReadLine(); } catch(Exception ex) { if (user.commandSession.tcpClient.Connected == false) { AddInfo(string.Format("客户端({0}断开连接!)", user.commandSession.tcpClient.Client.RemoteEndPoint)); } else { AddInfo("接收命令失败!" + ex.Message); } break; } if (receiveString == null) { AddInfo("接收字符串为null,结束线程!"); break; } AddInfo(string.Format("来自{0}:[{1}]", user.commandSession.tcpClient.Client.RemoteEndPoint, receiveString)); // 分解客户端发来的控制信息中的命令和参数 string command = receiveString; string param = string.Empty; int index = receiveString.IndexOf(' '); if (index != -1) { command = receiveString.Substring(0, index).ToUpper(); param = receiveString.Substring(command.Length).Trim(); } // 处理不需登录即可响应的命令(这里只处理QUIT) if (command == "QUIT") { // 关闭TCP连接并释放与其关联的所有资源 user.commandSession.Close(); return; } else { switch (user.loginOK) { // 等待用户输入用户名: case 0: CommandUser(user, command, param); break; // 等待用户输入密码 case 1: CommandPassword(user, command, param); break; // 用户名和密码验证正确后登陆 case 2: switch (command) { case "CWD": CommandCWD(user, param); break; case "PWD": CommandPWD(user); break; case "PASV": CommandPASV(user); break; case "PORT": CommandPORT(user, param); break; case "LIST": CommandLIST(user, param); break; case "NLIST": CommandLIST(user, param); break; // 处理下载文件命令 case "RETR": CommandRETR(user, param); break; // 处理上传文件命令 case "STOR": CommandSTOR(user, param); break; // 处理删除命令 case "DELE": CommandDELE(user, param); break; // 使用Type命令在ASCII和二进制模式进行变换 case "TYPE": CommandTYPE(user, param); break; default: sendString = "502 command is not implemented."; RepleyCommandToUser(user, sendString); break; } break; } } } } // 想客户端返回响应码 private void RepleyCommandToUser(User user, string str) { try { user.commandSession.streamWriter.WriteLine(str); AddInfo(string.Format("向客户端({0})发送[{1}]", user.commandSession.tcpClient.Client.RemoteEndPoint, str)); } catch { AddInfo(string.Format("向客户端({0})发送信息失败", user.commandSession.tcpClient.Client.RemoteEndPoint)); } } // 向屏幕输出显示状态信息(这里使用了委托机制) private delegate void AddInfoDelegate(string str); private void AddInfo(string str) { // 如果调用AddInfo()方法的线程与创建ListView控件的线程不在一个线程时 // 此时利用委托在创建ListView的线程上调用 if (lstboxStatus.InvokeRequired == true) { AddInfoDelegate d = new AddInfoDelegate(AddInfo); this.Invoke(d, str); } else { lstboxStatus.Items.Add(str); lstboxStatus.TopIndex = lstboxStatus.Items.Count - 1; lstboxStatus.ClearSelected(); } } #region 处理各个命令 #region 登录过程,即用户身份验证过程 // 处理USER命令,接收用户名但不进行验证 private void CommandUser(User user, string command, string param) { string sendString = string.Empty; if (command == "USER") { sendString = "331 USER command OK, password required."; user.userName = param; // 设置loginOk=1为了确保后面紧接的要求输入密码 // 1表示已接收到用户名,等到接收密码 user.loginOK = 1; } else { sendString = "501 USER command syntax error."; } RepleyCommandToUser(user, sendString); } // 处理PASS命令,验证用户名和密码 private void CommandPassword(User user, string command, string param) { string sendString = string.Empty; if (command == "PASS") { string password = null; if (users.TryGetValue(user.userName, out password)) { if (password == param) { sendString = "230 User logged in success"; // 2表示登录成功 user.loginOK = 2; } else { sendString = "530 Password incorrect."; } } else { sendString = "530 User name or password incorrect."; } } else { sendString = "501 PASS command Syntax error."; } RepleyCommandToUser(user, sendString); // 用户当前工作目录 user.currentDir = user.workDir; } #endregion #region 文件管理命令 // 处理CWD命令,改变工作目录 private void CommandCWD(User user, string temp) { string sendString = string.Empty; try { string dir = user.workDir.TrimEnd('/') + temp; // 是否为当前目录的子目录,且不包含父目录名称 if (Directory.Exists(dir)) { user.currentDir = dir; sendString = "250 Directory changed to '" + dir + "' successfully"; } else { sendString = "550 Directory '" + dir + "' does not exist"; } } catch { sendString = "502 Directory changed unsuccessfully"; } RepleyCommandToUser(user,sendString); } // 处理PWD命令,显示工作目录 private void CommandPWD(User user) { string sendString = string.Empty; sendString = "257 '" + user.currentDir + "' is the current directory"; RepleyCommandToUser(user, sendString); } // 处理LIST/NLIST命令,想客户端发送当前或指定目录下的所有文件名和子目录名 private void CommandLIST(User user, string parameter) { string sendString = string.Empty; DateTimeFormatInfo dateTimeFormat = new CultureInfo("en-US", true).DateTimeFormat; // 得到目录列表 string[] dir = Directory.GetDirectories(user.currentDir); if (string.IsNullOrEmpty(parameter) == false) { if (Directory.Exists(user.currentDir + parameter)) { dir = Directory.GetDirectories(user.currentDir + parameter); } else { string s = user.currentDir.TrimEnd('/'); user.currentDir = s.Substring(0, s.LastIndexOf("/") + 1); } } for (int i = 0; i < dir.Length; i++) { string folderName = Path.GetFileName(dir[i]); DirectoryInfo d = new DirectoryInfo(dir[i]); // 按下面的格式输出目录列表 sendString += @"dwr-\t" + Dns.GetHostName() + "\t" + dateTimeFormat.GetAbbreviatedMonthName(d.CreationTime.Month) + d.CreationTime.ToString(" dd yyyy") + "\t" + folderName + Environment.NewLine; } // 得到文件列表 string[] files = Directory.GetFiles(user.currentDir); if (string.IsNullOrEmpty(parameter) == false) { if (Directory.Exists(user.currentDir + parameter + "/")) { files = Directory.GetFiles(user.currentDir + parameter + "/"); } } for (int i = 0; i < files.Length; i++) { FileInfo f = new FileInfo(files[i]); string fileName = Path.GetFileName(files[i]); // 按下面的格式输出文件列表 sendString += "-wr-\t" + Dns.GetHostName() + "\t" + f.Length + " " + dateTimeFormat.GetAbbreviatedMonthName(f.CreationTime.Month) + f.CreationTime.ToString(" dd yyyy") + "\t" + fileName + Environment.NewLine; } // List命令指示获得FTP服务器上的文件列表字符串信息 // 所以调用List命令过程,客户端接受的指示一些字符串 // 所以isBinary是false,代表传输的是ASCII数据 // 但是为了防止isBinary因为 设置user.isBinary = false而改变 // 所以事先保存user.IsBinary的引用(此时为true),方便后面下载文件 bool isBinary = user.isBinary; user.isBinary = false; RepleyCommandToUser(user, "150 Opening ASCII data connection"); InitDataSession(user); SendByUserSession(user, sendString); RepleyCommandToUser(user, "226 Transfer complete"); user.isBinary = isBinary; } // 处理RETR命令,提供下载功能,将用户请求的文件发送给用户 private void CommandRETR(User user, string filename) { string sendString = ""; // 下载的文件全名 string path = user.currentDir + filename; FileStream filestream = new FileStream(path, FileMode.Open, FileAccess.Read); // 发送150到用户,表示服务器文件状态良好,将要打开数据连接传输文件 if (user.isBinary) { sendString = "150 Opening BINARY mode data connection for download"; } else { sendString = "150 Opening ASCII mode data connection for download"; } RepleyCommandToUser(user, sendString); InitDataSession(user); SendFileByUserSession(user, filestream); RepleyCommandToUser(user, "226 Transfer complete"); } // 处理STOR命令,提供上传功能,接收客户端上传的文件 private void CommandSTOR(User user, string filename) { string sendString = ""; // 上传的文件全名 string path = user.currentDir + filename; FileStream fs = new FileStream(path, FileMode.Create, FileAccess.Write); // 发送150到用户,表示服务器状态良好 if (user.isBinary) { sendString = "150 Opening BINARY mode data connection for upload"; } else { sendString = "150 Opeing ASCII mode data connection for upload"; } RepleyCommandToUser(user, sendString); InitDataSession(user); ReadFileByUserSession(user, fs); RepleyCommandToUser(user,"226 Transfer complete"); } // 处理DELE命令,提供删除功能,删除服务器上的文件 private void CommandDELE(User user, string filename) { string sendString = ""; // 删除的文件全名 string path = user.currentDir + filename; AddInfo("正在删除文件" + filename + "..."); File.Delete(path); AddInfo("删除成功"); sendString = "250 File " + filename + " has been deleted."; RepleyCommandToUser(user, sendString); } #endregion #region 模式设置命令 // 处理PASV命令, 使用被动模式进行传输 private void CommandPASV(User user) { string sendString = string.Empty; IPAddress localip = Dns.GetHostEntry("").AddressList[5]; // 被动模式,即服务器接收客户端的连接请求 // 被动模式下FTP服务器使用随机生成的端口进行传输数据 // 而主动模式下FTP服务器使用端口20进行数据传输 Random random = new Random(); int random1, random2; int port; while (true) { // 随机生成一个端口进行数据传输 random1 = random.Next(5, 200); random2 = random.Next(0, 200); // 生成的端口号控制>1024的随机端口 // 下面这个运算算法只是为了得到一个大于1024的端口值 port = random1 << 8 | random2; try { user.dataListener = new TcpListener(localip, port); AddInfo("TCP 数据连接已打开(被动模式)--" + localip.ToString() + ":" + port); } catch { continue; } user.isPassive = true; string temp = localip.ToString().Replace('.', ','); // 必须把端口号IP地址告诉客户端,客户端接收到响应命令后, // 再通过新的端口连接服务器的端口P,然后进行文件数据传输 sendString = "227 Entering Passive Mode(" + temp + "," + random1 + "," + random2 + ")"; RepleyCommandToUser(user, sendString); user.dataListener.Start(); break; } } // 处理PORT命令,使用主动模式进行传输 private void CommandPORT(User user, string portstring) { // 主动模式时,客户端必须告知服务器接收数据的端口号,PORT 命令格式为:PORT address // address参数的格式为i1、i2、i3、i4、p1、p2,其中i1、i2、i3、i4表示IP地址 // 下面通过.字符串来组合这四个参数得到IP地址 // p1、p2表示端口号,下面通过int.Parse(temp[4]) << 8) | int.Parse(temp[5] // 这个算法来获得一个大于1024的端口来发送给服务器 string sendString = string.Empty; string[] temp = portstring.Split(','); string ipString = "" + temp[0] + "." + temp[1] + "." + temp[2] + "." + temp[3]; // 客户端发出PORT命令把客户端的IP地址和随机的端口告诉服务器 int portNum = (int.Parse(temp[4]) << 8) | int.Parse(temp[5]); user.remoteEndPoint = new IPEndPoint(IPAddress.Parse(ipString), portNum); sendString = "200 PORT command successful."; // 服务器以接受到的客户端IP地址和端口为目标发起主动连接请求 // 服务器根据客户端发送过来的IP地址和端口主动发起与客户端建立连接 RepleyCommandToUser(user, sendString); } // 处理TYPE命令,设置数据传输方式 private void CommandTYPE(User user, string param) { string sendstring = ""; if (param == "I") { // 二进制 user.isBinary = true; sendstring = "220 Type set to I(Binary)"; } else { // ASCII方式 user.isBinary = false; sendstring = "330 Type set to A(ASCII)"; } RepleyCommandToUser(user, sendstring); } #endregion #endregion // 初始化数据连接 private void InitDataSession(User user) { TcpClient client = null; if (user.isPassive) { AddInfo("采用被动模式返回LIST目录和文件列表"); client = user.dataListener.AcceptTcpClient(); } else { AddInfo("采用主动模式向用户发送LIST目录和文件列表"); client = new TcpClient(); client.Connect(user.remoteEndPoint); } user.dataSession = new UserSeesion(client); } // 使用数据连接发送字符串 private void SendByUserSession(User user, string sendString) { AddInfo("向用户发送(字符串信息):[" + sendString + "]"); try { user.dataSession.streamWriter.WriteLine(sendString); AddInfo("发送完毕"); } finally { user.dataSession.Close(); } } // 使用数据连接发送文件流(客户端发送下载文件命令) private void SendFileByUserSession(User user, FileStream fs) { AddInfo("向用户发送(文件流):[..."); try { if (user.isBinary) { byte[] bytes = new byte[1024]; BinaryReader binaryReader = new BinaryReader(fs); int count = binaryReader.Read(bytes, 0, bytes.Length); while (count > 0) { user.dataSession.binaryWriter.Write(bytes, 0, count); user.dataSession.binaryWriter.Flush(); count = binaryReader.Read(bytes, 0, bytes.Length); } } else { StreamReader streamReader = new StreamReader(fs); while (streamReader.Peek() > -1) { user.dataSession.streamWriter.WriteLine(streamReader.ReadLine()); } } AddInfo("...]发送完毕!"); } finally { user.dataSession.Close(); fs.Close(); } } // 使用数据连接接收文件流(客户端发送上传文件功能) private void ReadFileByUserSession(User user, FileStream fs) { AddInfo("接收用户上传数据(文件流):[..."); try { if (user.isBinary) { byte[] bytes = new byte[1024]; BinaryWriter binaryWriter = new BinaryWriter(fs); int count = user.dataSession.binaryReader.Read(bytes, 0, bytes.Length); while (count > 0) { binaryWriter.Write(bytes, 0, count); binaryWriter.Flush(); count = user.dataSession.binaryReader.Read(bytes, 0, bytes.Length); } } else { StreamWriter streamWriter = new StreamWriter(fs); while (user.dataSession.streamReader.Peek() > -1) { streamWriter.Write(user.dataSession.streamReader.ReadLine()); streamWriter.Flush(); } } AddInfo("...]接收完毕"); } finally { user.dataSession.Close(); fs.Close(); } } private void label3_Click(object sender, EventArgs e) { } } }


【文件预览】:
FtpServer
----FtpServer()
--------FtpServer.suo(23KB)
--------.vs()
--------FtpServer()
--------FtpServer.sln(869B)

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