Initial commit

Internet/FtpClient.cs

@@ -0,0 +1,256 @@
+using System;
+using System.IO;
+using System.Net;
+using System.Net.Sockets;
+using System.Text;
+using System.Text.RegularExpressions;
+
+namespace Common.Internet
+{
+    public class FtpClient
+    {
+        #region Private constants
+
+        private const int DATA_SIZE = 4096;
+
+        #endregion
+
+        #region Private member variables
+
+        private Socket _controlSocket;      // The socket for sending control messsages
+        private Socket _dataSocket;         // The socket for transferring data
+        private int _timeout = 30000;       // The default send and receive timeouts
+
+        #endregion
+
+        #region Private socket management code
+
+        private Socket connectSocket(string server, int port)
+        {
+            // Resolve the server name into an IP Host
+            IPHostEntry ipHost = Dns.GetHostEntry(server);
+
+            // Get the first address from the host
+            IPAddress ipAddress = ipHost.AddressList[0];
+
+            // Create an end point on the host at the requested port
+            IPEndPoint ipEndPoint = new IPEndPoint(ipAddress, port);
+
+            // Create a TCP socket to the end point on the host
+            Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
+
+            // Set the send and receive timeouts requested
+            socket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReceiveTimeout, _timeout);
+            socket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.SendTimeout, _timeout);
+
+            // Make the connection
+            socket.Connect(ipEndPoint);
+
+            return socket;
+        }
+
+        private static void disconnectSocket(ref Socket targetSocket)
+        {
+            if (targetSocket != null)
+            {
+                targetSocket.Shutdown(SocketShutdown.Both);
+                targetSocket.Close();
+                targetSocket = null;
+            }
+        }
+
+        private static void sendSocketMessage(Socket targetSocket, string message)
+        {
+            sendSocketMessage(targetSocket, message, true);
+        }
+
+        private static void sendSocketMessage(Socket targetSocket, string message, bool trailingNewline)
+        {
+            // Default to sending just the message
+            string send = message;
+
+            // If a trailing newline is requested then add that to the string
+            if (trailingNewline) send += "\r\n";
+
+            // Convert the requested message into a byte array
+            byte[] rawData = Encoding.ASCII.GetBytes(send);
+
+            // Send the message and get the byte count back
+            targetSocket.Send(rawData);
+        }
+
+        private static string receiveSocketMessage(Socket sourceSocket, bool stripTrailingNewline)
+        {
+            // Initialize the decoded string message to return
+            string message = string.Empty; 
+
+            // Initialize the array of all lines
+            string[] lines;
+
+            do
+            {
+                // Initialize the byte array buffer
+                byte[] line = new byte[DATA_SIZE];
+
+                // Retrieve the data and get the byte count
+                int bytesReceived = sourceSocket.Receive(line);
+
+                // Decode the string into a string for the current line
+                string sLine = Encoding.ASCII.GetString(line, 0, bytesReceived);
+
+                // Replace the CR/LF pairs with just a LF
+                sLine.Replace("\r\n", "\n");
+
+                // Split the message into an array of lines (we might get more than one)
+                lines = sLine.Split('\n');
+
+                // Add this line to the main return string
+                message += sLine;
+            } while (lines[lines.Length - 2].Substring(3, 1) == "-");
+
+            // If requested to remove the trailing newline we should do it now
+            if (stripTrailingNewline && message.EndsWith("\n"))
+            {
+                message = message.Remove(message.Length - 1, 1);
+            }
+
+            return message;
+        }
+
+        public int GetResponseCode(string message)
+        {
+            // Get the FTP response code from the string message
+            return Convert.ToInt32(message.Substring(1, 3));
+        }
+
+        #endregion
+
+        #region Public interface methods
+
+        public void Connect(string server)
+        {
+            Connect(server, 21, _timeout);
+        }
+
+        public void Connect(string server, int port, int timeout)
+        {
+            // Store the timeout requested so we can use it later
+            _timeout = timeout * 1000;
+
+            // If we are currently connected in any way we should disconnect
+            if (_controlSocket != null || _dataSocket != null) Disconnect();
+
+            // Create and connect the control socket
+            _controlSocket = connectSocket(server, port);
+
+            // Retrieve the header message
+            receiveSocketMessage(_controlSocket, true);
+        }
+
+        public void Upload(string source)
+        {
+            string targetFile;
+
+            if (source.Contains(@"\"))
+                targetFile = source.Substring(source.LastIndexOf(@"\") + 1);
+            else
+                targetFile = source;
+
+            // Create a stream reader for the file
+            StreamReader streamReader = new StreamReader(source);
+
+            // Upload the file
+            Upload(streamReader.BaseStream, targetFile);
+        }
+
+        public void Upload(Stream source, string targetFile)
+        {
+            // Send a command requesting the passive port to connect to
+            sendSocketMessage(_controlSocket, "PASV");
+
+            // Get the response back with the data we need
+            string message = receiveSocketMessage(_controlSocket, true);
+
+            message = message.Replace("(", "<");
+            message = message.Replace(")", ">");
+
+            // Create a regular expression to get the port data out
+            Match match = new Regex("<(?<oct1>.*),(?<oct2>.*),(?<oct3>.*),(?<oct4>.*),(?<highport>.*),(?<lowport>.*)>").Match(message);
+
+            // Reconstruct the IP address the server wants
+            string address = match.Groups["oct1"].Value + "." + match.Groups["oct2"].Value + "." +
+                             match.Groups["oct3"].Value + "." + match.Groups["oct4"].Value;
+
+            // Reconstruct the port the server wants
+            int port = Convert.ToInt32(match.Groups["highport"].Value) * 256 +
+                       Convert.ToInt32(match.Groups["lowport"].Value);
+
+            // Connect the socket to that port
+            _dataSocket = connectSocket(address, port);
+
+            // Send the command requesting to store a file
+            sendSocketMessage(_controlSocket, "STOR " + targetFile);
+
+            // Get the response back
+            receiveSocketMessage(_controlSocket, false);
+
+            // Bring the stream to the beginning if it supports seek
+            if (source.CanSeek) source.Seek(0, SeekOrigin.Begin);
+
+            // Loop until the end of the file
+            while (source.Length != source.Position)
+            {
+                // Initialize the byte array buffer
+                byte[] rawMessage = new byte[DATA_SIZE];
+
+                // Get data from the stream
+                int bytesRead = source.Read(rawMessage, 0, DATA_SIZE);
+
+                // Send the data down the data socket
+                _dataSocket.Send(rawMessage, bytesRead, 0);
+            }
+
+            // Close the data socket
+            disconnectSocket(ref _dataSocket);
+
+            // Get the response back
+            receiveSocketMessage(_controlSocket, false);
+        }
+
+        public void Download(string sourceFile, string targetFile)
+        {
+        }
+
+        public void Logon(string userName, string password)
+        {
+            // Send the command to indicate the user we want
+            sendSocketMessage(_controlSocket, "USER " + userName);
+
+            receiveSocketMessage(_controlSocket, true);
+
+            // Send the command to indicate the password we want
+            sendSocketMessage(_controlSocket, "PASS " + password);
+
+            receiveSocketMessage(_controlSocket, true);
+        }
+
+        public void Logoff()
+        {
+            // Send the comment to close the current session
+            sendSocketMessage(_controlSocket, "QUIT");
+
+            receiveSocketMessage(_controlSocket, true);
+        }
+
+        public void Disconnect()
+        {
+            // Close and clear the data socket
+            disconnectSocket(ref _dataSocket);
+
+            // Close and clear the control socket
+            disconnectSocket(ref _controlSocket);
+        }
+
+        #endregion
+    }
+}