mcs/class/System/System.Net/FtpWebRequest.cs

   1 //
   2 // System.Net.FtpWebRequest.cs
   3 //
   4 // Authors:
   5 //      Carlos Alberto Cortez (calberto.cortez@gmail.com)
   6 //
   7 // (c) Copyright 2006 Novell, Inc. (http://www.novell.com)
   8 //
   9 #if NET_2_0
  10
  11 using System;
  12 using System.IO;
  13 using System.Net.Sockets;
  14 using System.Text;
  15 using System.Threading;
  16 using System.Net.Cache;
  17 using System.Security.Cryptography.X509Certificates;
  18 using System.Net;
  19 using System.Net.Security;
  20 using System.Security.Authentication;
  21
  22 namespace System.Net
  23 {
  24         public sealed class FtpWebRequest : WebRequest
  25         {
  26                 Uri requestUri;
  27                 string file_name; // By now, used for upload
  28                 ServicePoint servicePoint;
  29                 Stream origDataStream;
  30                 Stream dataStream;
  31                 Stream controlStream;
  32                 StreamReader controlReader;
  33                 NetworkCredential credentials;
  34                 IPHostEntry hostEntry;
  35                 IPEndPoint localEndPoint;
  36                 IWebProxy proxy;
  37                 int timeout = 100000;
  38                 int rwTimeout = 300000;
  39                 long offset = 0;
  40                 bool binary = true;
  41                 bool enableSsl = false;
  42                 bool usePassive = true;
  43                 bool keepAlive = false;
  44                 string method = WebRequestMethods.Ftp.DownloadFile;
  45                 string renameTo;
  46                 object locker = new object ();
  47
  48                 RequestState requestState = RequestState.Before;
  49                 FtpAsyncResult asyncResult;
  50                 FtpWebResponse ftpResponse;
  51                 Stream requestStream;
  52                 string initial_path;
  53
  54                 const string ChangeDir = "CWD";
  55                 const string UserCommand = "USER";
  56                 const string PasswordCommand = "PASS";
  57                 const string TypeCommand = "TYPE";
  58                 const string PassiveCommand = "PASV";
  59                 const string PortCommand = "PORT";
  60                 const string AbortCommand = "ABOR";
  61                 const string AuthCommand = "AUTH";
  62                 const string RestCommand = "REST";
  63                 const string RenameFromCommand = "RNFR";
  64                 const string RenameToCommand = "RNTO";
  65                 const string QuitCommand = "QUIT";
  66                 const string EOL = "\r\n"; // Special end of line
  67
  68                 enum RequestState
  69                 {
  70                         Before,
  71                         Scheduled,
  72                         Connecting,
  73                         Authenticating,
  74                         OpeningData,
  75                         TransferInProgress,
  76                         Finished,
  77                         Aborted,
  78                         Error
  79                 }
  80
  81                 // sorted commands
  82                 static readonly string [] supportedCommands = new string [] {
  83                         WebRequestMethods.Ftp.AppendFile, // APPE
  84                         WebRequestMethods.Ftp.DeleteFile, // DELE
  85                         WebRequestMethods.Ftp.ListDirectoryDetails, // LIST
  86                         WebRequestMethods.Ftp.GetDateTimestamp, // MDTM
  87                         WebRequestMethods.Ftp.MakeDirectory, // MKD
  88                         WebRequestMethods.Ftp.ListDirectory, // NLST
  89                         WebRequestMethods.Ftp.PrintWorkingDirectory, // PWD
  90                         WebRequestMethods.Ftp.Rename, // RENAME
  91                         WebRequestMethods.Ftp.DownloadFile, // RETR
  92                         WebRequestMethods.Ftp.RemoveDirectory, // RMD
  93                         WebRequestMethods.Ftp.GetFileSize, // SIZE
  94                         WebRequestMethods.Ftp.UploadFile, // STOR
  95                         WebRequestMethods.Ftp.UploadFileWithUniqueName // STUR
  96                         };
  97
  98                 internal FtpWebRequest (Uri uri)
  99                 {
 100                         this.requestUri = uri;
 101                         this.proxy = GlobalProxySelection.Select;
 102                 }
 103
 104                 static Exception GetMustImplement ()
 105                 {
 106                         return new NotImplementedException ();
 107                 }
 108
 109                 [MonoTODO]
 110                 public X509CertificateCollection ClientCertificates
 111                 {
 112                         get {
 113                                 throw GetMustImplement ();
 114                         }
 115                         set {
 116                                 throw GetMustImplement ();
 117                         }
 118                 }
 119
 120                 [MonoTODO]
 121                 public override string ConnectionGroupName
 122                 {
 123                         get {
 124                                 throw GetMustImplement ();
 125                         }
 126                         set {
 127                                 throw GetMustImplement ();
 128                         }
 129                 }
 130
 131                 public override string ContentType {
 132                         get {
 133                                 throw new NotSupportedException ();
 134                         }
 135                         set {
 136                                 throw new NotSupportedException ();
 137                         }
 138                 }
 139
 140                 public override long ContentLength {
 141                         get {
 142                                 return 0;
 143                         }
 144                         set {
 145                                 // DO nothing
 146                         }
 147                 }
 148
 149                 public long ContentOffset {
 150                         get {
 151                                 return offset;
 152                         }
 153                         set {
 154                                 CheckRequestStarted ();
 155                                 if (value < 0)
 156                                         throw new ArgumentOutOfRangeException ();
 157
 158                                 offset = value;
 159                         }
 160                 }
 161
 162                 public override ICredentials Credentials {
 163                         get {
 164                                 return credentials;
 165                         }
 166                         set {
 167                                 CheckRequestStarted ();
 168                                 if (value == null)
 169                                         throw new ArgumentNullException ();
 170                                 if (!(value is NetworkCredential))
 171                                         throw new ArgumentException ();
 172
 173                                 credentials = value as NetworkCredential;
 174                         }
 175                 }
 176
 177                 [MonoTODO]
 178                 public static new RequestCachePolicy DefaultCachePolicy
 179                 {
 180                         get {
 181                                 throw GetMustImplement ();
 182                         }
 183                         set {
 184                                 throw GetMustImplement ();
 185                         }
 186                 }
 187
 188                 public bool EnableSsl {
 189                         get {
 190                                 return enableSsl;
 191                         }
 192                         set {
 193                                 CheckRequestStarted ();
 194                                 enableSsl = value;
 195                         }
 196                 }
 197
 198                 [MonoTODO]
 199                 public override WebHeaderCollection Headers
 200                 {
 201                         get {
 202                                 throw GetMustImplement ();
 203                         }
 204                         set {
 205                                 throw GetMustImplement ();
 206                         }
 207                 }
 208
 209                 [MonoTODO ("We don't support KeepAlive = true")]
 210                 public bool KeepAlive {
 211                         get {
 212                                 return keepAlive;
 213                         }
 214                         set {
 215                                 CheckRequestStarted ();
 216                                 //keepAlive = value;
 217                         }
 218                 }
 219
 220                 public override string Method {
 221                         get {
 222                                 return method;
 223                         }
 224                         set {
 225                                 CheckRequestStarted ();
 226                                 if (value == null)
 227                                         throw new ArgumentNullException ("Method string cannot be null");
 228
 229                                 if (value.Length == 0 || Array.BinarySearch (supportedCommands, value) < 0)
 230                                         throw new ArgumentException ("Method not supported", "value");
 231
 232                                 method = value;
 233                         }
 234                 }
 235
 236                 public override bool PreAuthenticate {
 237                         get {
 238                                 throw new NotSupportedException ();
 239                         }
 240                         set {
 241                                 throw new NotSupportedException ();
 242                         }
 243                 }
 244
 245                 public override IWebProxy Proxy {
 246                         get {
 247                                 return proxy;
 248                         }
 249                         set {
 250                                 CheckRequestStarted ();
 251                                 if (value == null)
 252                                         throw new ArgumentNullException ();
 253
 254                                 proxy = value;
 255                         }
 256                 }
 257
 258                 public int ReadWriteTimeout {
 259                         get {
 260                                 return rwTimeout;
 261                         }
 262                         set {
 263                                 CheckRequestStarted ();
 264
 265                                 if (value < - 1)
 266                                         throw new ArgumentOutOfRangeException ();
 267                                 else
 268                                         rwTimeout = value;
 269                         }
 270                 }
 271
 272                 public string RenameTo {
 273                         get {
 274                                 return renameTo;
 275                         }
 276                         set {
 277                                 CheckRequestStarted ();
 278                                 if (value == null || value.Length == 0)
 279                                         throw new ArgumentException ("RenameTo value can't be null or empty", "RenameTo");
 280
 281                                 renameTo = value;
 282                         }
 283                 }
 284
 285                 public override Uri RequestUri {
 286                         get {
 287                                 return requestUri;
 288                         }
 289                 }
 290
 291                 public ServicePoint ServicePoint {
 292                         get {
 293                                 return GetServicePoint ();
 294                         }
 295                 }
 296
 297                 public bool UsePassive {
 298                         get {
 299                                 return usePassive;
 300                         }
 301                         set {
 302                                 CheckRequestStarted ();
 303                                 usePassive = value;
 304                         }
 305                 }
 306
 307                 [MonoTODO]
 308                 public override bool UseDefaultCredentials
 309                 {
 310                         get {
 311                                 throw GetMustImplement ();
 312                         }
 313                         set {
 314                                 throw GetMustImplement ();
 315                         }
 316                 }
 317
 318                 public bool UseBinary {
 319                         get {
 320                                 return binary;
 321                         } set {
 322                                 CheckRequestStarted ();
 323                                 binary = value;
 324                         }
 325                 }
 326
 327                 public override int Timeout {
 328                         get {
 329                                 return timeout;
 330                         }
 331                         set {
 332                                 CheckRequestStarted ();
 333
 334                                 if (value < -1)
 335                                         throw new ArgumentOutOfRangeException ();
 336                                 else
 337                                         timeout = value;
 338                         }
 339                 }
 340
 341                 string DataType {
 342                         get {
 343                                 return binary ? "I" : "A";
 344                         }
 345                 }
 346
 347                 RequestState State {
 348                         get {
 349                                 lock (locker) {
 350                                         return requestState;
 351                                 }
 352                         }
 353
 354                         set {
 355                                 lock (locker) {
 356                                         CheckIfAborted ();
 357                                         CheckFinalState ();
 358                                         requestState = value;
 359                                 }
 360                         }
 361                 }
 362
 363                 public override void Abort () {
 364                         lock (locker) {
 365                                 if (State == RequestState.TransferInProgress) {
 366                                         /*FtpStatus status = */
 367                                         SendCommand (false, AbortCommand);
 368                                 }
 369
 370                                 if (!InFinalState ()) {
 371                                         State = RequestState.Aborted;
 372                                         ftpResponse = new FtpWebResponse (this, requestUri, method, FtpStatusCode.FileActionAborted, "Aborted by request");
 373                                 }
 374                         }
 375                 }
 376
 377                 public override IAsyncResult BeginGetResponse (AsyncCallback callback, object state) {
 378                         if (asyncResult != null && !asyncResult.IsCompleted) {
 379                                 throw new InvalidOperationException ("Cannot re-call BeginGetRequestStream/BeginGetResponse while a previous call is still in progress");
 380                         }
 381
 382                         CheckIfAborted ();
 383
 384                         asyncResult = new FtpAsyncResult (callback, state);
 385
 386                         lock (locker) {
 387                                 if (InFinalState ())
 388                                         asyncResult.SetCompleted (true, ftpResponse);
 389                                 else {
 390                                         if (State == RequestState.Before)
 391                                                 State = RequestState.Scheduled;
 392
 393                                         Thread thread = new Thread (ProcessRequest);
 394                                         thread.Start ();
 395                                 }
 396                         }
 397
 398                         return asyncResult;
 399                 }
 400
 401                 public override WebResponse EndGetResponse (IAsyncResult asyncResult) {
 402                         if (asyncResult == null)
 403                                 throw new ArgumentNullException ("AsyncResult cannot be null!");
 404
 405                         if (!(asyncResult is FtpAsyncResult) || asyncResult != this.asyncResult)
 406                                 throw new ArgumentException ("AsyncResult is from another request!");
 407
 408                         FtpAsyncResult asyncFtpResult = (FtpAsyncResult) asyncResult;
 409                         if (!asyncFtpResult.WaitUntilComplete (timeout, false)) {
 410                                 Abort ();
 411                                 throw new WebException ("Transfer timed out.", WebExceptionStatus.Timeout);
 412                         }
 413
 414                         CheckIfAborted ();
 415
 416                         asyncResult = null;
 417
 418                         if (asyncFtpResult.GotException)
 419                                 throw asyncFtpResult.Exception;
 420
 421                         return asyncFtpResult.Response;
 422                 }
 423
 424                 public override WebResponse GetResponse () {
 425                         IAsyncResult asyncResult = BeginGetResponse (null, null);
 426                         return EndGetResponse (asyncResult);
 427                 }
 428
 429                 public override IAsyncResult BeginGetRequestStream (AsyncCallback callback, object state) {
 430                         if (method != WebRequestMethods.Ftp.UploadFile && method != WebRequestMethods.Ftp.UploadFileWithUniqueName &&
 431                                         method != WebRequestMethods.Ftp.AppendFile)
 432                                 throw new ProtocolViolationException ();
 433
 434                         lock (locker) {
 435                                 CheckIfAborted ();
 436
 437                                 if (State != RequestState.Before)
 438                                         throw new InvalidOperationException ("Cannot re-call BeginGetRequestStream/BeginGetResponse while a previous call is still in progress");
 439
 440                                 State = RequestState.Scheduled;
 441                         }
 442
 443                         asyncResult = new FtpAsyncResult (callback, state);
 444                         Thread thread = new Thread (ProcessRequest);
 445                         thread.Start ();
 446
 447                         return asyncResult;
 448                 }
 449
 450                 public override Stream EndGetRequestStream (IAsyncResult asyncResult) {
 451                         if (asyncResult == null)
 452                                 throw new ArgumentNullException ("asyncResult");
 453
 454                         if (!(asyncResult is FtpAsyncResult))
 455                                 throw new ArgumentException ("asyncResult");
 456
 457                         if (State == RequestState.Aborted) {
 458                                 throw new WebException ("Request aborted", WebExceptionStatus.RequestCanceled);
 459                         }
 460
 461                         if (asyncResult != this.asyncResult)
 462                                 throw new ArgumentException ("AsyncResult is from another request!");
 463
 464                         FtpAsyncResult res = (FtpAsyncResult) asyncResult;
 465
 466                         if (!res.WaitUntilComplete (timeout, false)) {
 467                                 Abort ();
 468                                 throw new WebException ("Request timed out");
 469                         }
 470
 471                         if (res.GotException)
 472                                 throw res.Exception;
 473
 474                         return res.Stream;
 475                 }
 476
 477                 public override Stream GetRequestStream () {
 478                         IAsyncResult asyncResult = BeginGetRequestStream (null, null);
 479                         return EndGetRequestStream (asyncResult);
 480                 }
 481
 482                 ServicePoint GetServicePoint ()
 483                 {
 484                         if (servicePoint == null)
 485                                 servicePoint = ServicePointManager.FindServicePoint (requestUri, proxy);
 486
 487                         return servicePoint;
 488                 }
 489
 490                 // Probably move some code of command connection here
 491                 void ResolveHost ()
 492                 {
 493                         CheckIfAborted ();
 494                         hostEntry = GetServicePoint ().HostEntry;
 495
 496                         if (hostEntry == null) {
 497                                 ftpResponse.UpdateStatus (new FtpStatus(FtpStatusCode.ActionAbortedLocalProcessingError, "Cannot resolve server name"));
 498                                 throw new WebException ("The remote server name could not be resolved: " + requestUri,
 499                                         null, WebExceptionStatus.NameResolutionFailure, ftpResponse);
 500                         }
 501                 }
 502
 503                 void ProcessRequest () {
 504
 505                         if (State == RequestState.Scheduled) {
 506                                 ftpResponse = new FtpWebResponse (this, requestUri, method, keepAlive);
 507
 508                                 try {
 509                                         ProcessMethod ();
 510                                         //State = RequestState.Finished;
 511                                         //finalResponse = ftpResponse;
 512                                         asyncResult.SetCompleted (false, ftpResponse);
 513                                 }
 514                                 catch (Exception e) {
 515                                         State = RequestState.Error;
 516                                         SetCompleteWithError (e);
 517                                 }
 518                         }
 519                         else {
 520                                 if (InProgress ()) {
 521                                         FtpStatus status = GetResponseStatus ();
 522
 523                                         ftpResponse.UpdateStatus (status);
 524
 525                                         if (ftpResponse.IsFinal ()) {
 526                                                 State = RequestState.Finished;
 527                                         }
 528                                 }
 529
 530                                 asyncResult.SetCompleted (false, ftpResponse);
 531                         }
 532                 }
 533
 534                 void SetType ()
 535                 {
 536                         if (binary) {
 537                                 FtpStatus status = SendCommand (TypeCommand, DataType);
 538                                 if ((int) status.StatusCode < 200 || (int) status.StatusCode >= 300)
 539                                         throw CreateExceptionFromResponse (status);
 540                         }
 541                 }
 542
 543                 string GetRemoteFolderPath (Uri uri)
 544                 {
 545                         string result;
 546                         string local_path = Uri.UnescapeDataString (uri.LocalPath);
 547                         if (initial_path == null || initial_path == "/") {
 548                                 result = local_path;
 549                         } else {
 550                                 if (local_path [0] == '/')
 551                                         local_path = local_path.Substring (1);
 552
 553                                 Uri initial = new Uri ("ftp://dummy-host" + initial_path);
 554                                 result = new Uri (initial, local_path).LocalPath;
 555                         }
 556
 557                         int last = result.LastIndexOf ('/');
 558                         if (last == -1)
 559                                 return null;
 560
 561                         return result.Substring (0, last + 1);
 562                 }
 563
 564                 void CWDAndSetFileName (Uri uri)
 565                 {
 566                         string remote_folder = GetRemoteFolderPath (uri);
 567                         FtpStatus status;
 568                         if (remote_folder != null) {
 569                                 status = SendCommand (ChangeDir, remote_folder);
 570                                 if ((int) status.StatusCode < 200 || (int) status.StatusCode >= 300)
 571                                         throw CreateExceptionFromResponse (status);
 572
 573                                 int last = uri.LocalPath.LastIndexOf ('/');
 574                                 if (last >= 0) {
 575                                         file_name = Uri.UnescapeDataString (uri.LocalPath.Substring (last + 1));
 576                                 }
 577                         }
 578                 }
 579
 580                 void ProcessMethod ()
 581                 {
 582                         State = RequestState.Connecting;
 583
 584                         ResolveHost ();
 585
 586                         OpenControlConnection ();
 587                         CWDAndSetFileName (requestUri);
 588                         SetType ();
 589
 590                         switch (method) {
 591                         // Open data connection and receive data
 592                         case WebRequestMethods.Ftp.DownloadFile:
 593                         case WebRequestMethods.Ftp.ListDirectory:
 594                         case WebRequestMethods.Ftp.ListDirectoryDetails:
 595                                 DownloadData ();
 596                                 break;
 597                         // Open data connection and send data
 598                         case WebRequestMethods.Ftp.AppendFile:
 599                         case WebRequestMethods.Ftp.UploadFile:
 600                         case WebRequestMethods.Ftp.UploadFileWithUniqueName:
 601                                 UploadData ();
 602                                 break;
 603                         // Get info from control connection
 604                         case WebRequestMethods.Ftp.GetFileSize:
 605                         case WebRequestMethods.Ftp.GetDateTimestamp:
 606                         case WebRequestMethods.Ftp.PrintWorkingDirectory:
 607                         case WebRequestMethods.Ftp.MakeDirectory:
 608                         case WebRequestMethods.Ftp.Rename:
 609                         case WebRequestMethods.Ftp.DeleteFile:
 610                                 ProcessSimpleMethod ();
 611                                 break;
 612                         default: // What to do here?
 613                                 throw new Exception (String.Format ("Support for command {0} not implemented yet", method));
 614                         }
 615
 616                         CheckIfAborted ();
 617                 }
 618
 619                 private void CloseControlConnection () {
 620                         if (controlStream != null) {
 621                                 SendCommand (QuitCommand);
 622                                 controlStream.Close ();
 623                                 controlStream = null;
 624                         }
 625                 }
 626
 627                 internal void CloseDataConnection () {
 628                         if(origDataStream != null) {
 629                                 origDataStream.Close ();
 630                                 origDataStream = null;
 631                         }
 632                 }
 633
 634                 private void CloseConnection () {
 635                         CloseControlConnection ();
 636                         CloseDataConnection ();
 637                 }
 638
 639                 void ProcessSimpleMethod ()
 640                 {
 641                         State = RequestState.TransferInProgress;
 642
 643                         FtpStatus status;
 644
 645                         if (method == WebRequestMethods.Ftp.PrintWorkingDirectory)
 646                                 method = "PWD";
 647
 648                         if (method == WebRequestMethods.Ftp.Rename)
 649                                 method = RenameFromCommand;
 650
 651                         status = SendCommand (method, file_name);
 652
 653                         ftpResponse.Stream = Stream.Null;
 654
 655                         string desc = status.StatusDescription;
 656
 657                         switch (method) {
 658                         case WebRequestMethods.Ftp.GetFileSize: {
 659                                         if (status.StatusCode != FtpStatusCode.FileStatus)
 660                                                 throw CreateExceptionFromResponse (status);
 661
 662                                         int i, len;
 663                                         long size;
 664                                         for (i = 4, len = 0; i < desc.Length && Char.IsDigit (desc [i]); i++, len++)
 665                                                 ;
 666
 667                                         if (len == 0)
 668                                                 throw new WebException ("Bad format for server response in " + method);
 669
 670                                         if (!Int64.TryParse (desc.Substring (4, len), out size))
 671                                                 throw new WebException ("Bad format for server response in " + method);
 672
 673                                         ftpResponse.contentLength = size;
 674                                 }
 675                                 break;
 676                         case WebRequestMethods.Ftp.GetDateTimestamp:
 677                                 if (status.StatusCode != FtpStatusCode.FileStatus)
 678                                         throw CreateExceptionFromResponse (status);
 679                                 ftpResponse.LastModified = DateTime.ParseExact (desc.Substring (4), "yyyyMMddHHmmss", null);
 680                                 break;
 681                         case WebRequestMethods.Ftp.MakeDirectory:
 682                                 if (status.StatusCode != FtpStatusCode.PathnameCreated)
 683                                         throw CreateExceptionFromResponse (status);
 684                                 break;
 685                         case ChangeDir:
 686                                 method = WebRequestMethods.Ftp.PrintWorkingDirectory;
 687
 688                                 if (status.StatusCode != FtpStatusCode.FileActionOK)
 689                                         throw CreateExceptionFromResponse (status);
 690
 691                                 status = SendCommand (method);
 692
 693                                 if (status.StatusCode != FtpStatusCode.PathnameCreated)
 694                                         throw CreateExceptionFromResponse (status);
 695                                 break;
 696                         case RenameFromCommand:
 697                                 method = WebRequestMethods.Ftp.Rename;
 698                                 if (status.StatusCode != FtpStatusCode.FileCommandPending)
 699                                         throw CreateExceptionFromResponse (status);
 700                                 // Pass an empty string if RenameTo wasn't specified
 701                                 status = SendCommand (RenameToCommand, renameTo != null ? renameTo : String.Empty);
 702                                 if (status.StatusCode != FtpStatusCode.FileActionOK)
 703                                         throw CreateExceptionFromResponse (status);
 704                                 break;
 705                         case WebRequestMethods.Ftp.DeleteFile:
 706                                 if (status.StatusCode != FtpStatusCode.FileActionOK)  {
 707                                         throw CreateExceptionFromResponse (status);
 708                                 }
 709                                 break;
 710                         }
 711
 712                         State = RequestState.Finished;
 713                 }
 714
 715                 void UploadData ()
 716                 {
 717                         State = RequestState.OpeningData;
 718
 719                         OpenDataConnection ();
 720
 721                         State = RequestState.TransferInProgress;
 722                         requestStream = new FtpDataStream (this, dataStream, false);
 723                         asyncResult.Stream = requestStream;
 724                 }
 725
 726                 void DownloadData ()
 727                 {
 728                         State = RequestState.OpeningData;
 729
 730                         OpenDataConnection ();
 731
 732                         State = RequestState.TransferInProgress;
 733                         ftpResponse.Stream = new FtpDataStream (this, dataStream, true);
 734                 }
 735
 736                 void CheckRequestStarted ()
 737                 {
 738                         if (State != RequestState.Before)
 739                                 throw new InvalidOperationException ("There is a request currently in progress");
 740                 }
 741
 742                 void OpenControlConnection ()
 743                 {
 744                         Exception exception = null;
 745                         Socket sock = null;
 746                         foreach (IPAddress address in hostEntry.AddressList) {
 747                                 sock = new Socket (address.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
 748
 749                                 IPEndPoint remote = new IPEndPoint (address, requestUri.Port);
 750
 751                                 if (!ServicePoint.CallEndPointDelegate (sock, remote)) {
 752                                         sock.Close ();
 753                                         sock = null;
 754                                 } else {
 755                                         try {
 756                                                 sock.Connect (remote);
 757                                                 localEndPoint = (IPEndPoint) sock.LocalEndPoint;
 758                                                 break;
 759                                         } catch (SocketException exc) {
 760                                                 exception = exc;
 761                                                 sock.Close ();
 762                                                 sock = null;
 763                                         }
 764                                 }
 765                         }
 766
 767                         // Couldn't connect to any address
 768                         if (sock == null)
 769                                 throw new WebException ("Unable to connect to remote server", exception,
 770                                                 WebExceptionStatus.UnknownError, ftpResponse);
 771
 772                         controlStream = new NetworkStream (sock);
 773                         controlReader = new StreamReader (controlStream, Encoding.ASCII);
 774
 775                         State = RequestState.Authenticating;
 776
 777                         Authenticate ();
 778                         FtpStatus status = SendCommand ("OPTS", "utf8", "on");
 779                         // ignore status for OPTS
 780                         status = SendCommand (WebRequestMethods.Ftp.PrintWorkingDirectory);
 781                         initial_path = GetInitialPath (status);
 782                 }
 783
 784                 static string GetInitialPath (FtpStatus status)
 785                 {
 786                         int s = (int) status.StatusCode;
 787                         if (s < 200 || s > 300 || status.StatusDescription.Length <= 4)
 788                                 throw new WebException ("Error getting current directory: " + status.StatusDescription, null,
 789                                                 WebExceptionStatus.UnknownError, null);
 790
 791                         string msg = status.StatusDescription.Substring (4);
 792                         if (msg [0] == '"') {
 793                                 int next_quote = msg.IndexOf ('\"', 1);
 794                                 if (next_quote == -1)
 795                                         throw new WebException ("Error getting current directory: PWD -> " + status.StatusDescription, null,
 796                                                                 WebExceptionStatus.UnknownError, null);
 797
 798                                 msg = msg.Substring (1, next_quote - 1);
 799                         }
 800
 801                         if (!msg.EndsWith ("/"))
 802                                 msg += "/";
 803                         return msg;
 804                 }
 805
 806                 // Probably we could do better having here a regex
 807                 Socket SetupPassiveConnection (string statusDescription)
 808                 {
 809                         // Current response string
 810                         string response = statusDescription;
 811                         if (response.Length < 4)
 812                                 throw new WebException ("Cannot open passive data connection");
 813
 814                         // Look for first digit after code
 815                         int i;
 816                         for (i = 3; i < response.Length && !Char.IsDigit (response [i]); i++)
 817                                 ;
 818                         if (i >= response.Length)
 819                                 throw new WebException ("Cannot open passive data connection");
 820
 821                         // Get six elements
 822                         string [] digits = response.Substring (i).Split (new char [] {','}, 6);
 823                         if (digits.Length != 6)
 824                                 throw new WebException ("Cannot open passive data connection");
 825
 826                         // Clean non-digits at the end of last element
 827                         int j;
 828                         for (j = digits [5].Length - 1; j >= 0 && !Char.IsDigit (digits [5][j]); j--)
 829                                 ;
 830                         if (j < 0)
 831                                 throw new WebException ("Cannot open passive data connection");
 832
 833                         digits [5] = digits [5].Substring (0, j + 1);
 834
 835                         IPAddress ip;
 836                         try {
 837                                 ip = IPAddress.Parse (String.Join (".", digits, 0, 4));
 838                         } catch (FormatException) {
 839                                 throw new WebException ("Cannot open passive data connection");
 840                         }
 841
 842                         // Get the port
 843                         int p1, p2, port;
 844                         if (!Int32.TryParse (digits [4], out p1) || !Int32.TryParse (digits [5], out p2))
 845                                 throw new WebException ("Cannot open passive data connection");
 846
 847                         port = (p1 << 8) + p2; // p1 * 256 + p2
 848                         //port = p1 * 256 + p2;
 849                         if (port < IPEndPoint.MinPort || port > IPEndPoint.MaxPort)
 850                                 throw new WebException ("Cannot open passive data connection");
 851
 852                         IPEndPoint ep = new IPEndPoint (ip, port);
 853                         Socket sock = new Socket (ep.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
 854                         try {
 855                                 sock.Connect (ep);
 856                         } catch (SocketException) {
 857                                 sock.Close ();
 858                                 throw new WebException ("Cannot open passive data connection");
 859                         }
 860
 861                         return sock;
 862                 }
 863
 864                 Exception CreateExceptionFromResponse (FtpStatus status)
 865                 {
 866                         FtpWebResponse ftpResponse = new FtpWebResponse (this, requestUri, method, status);
 867
 868                         WebException exc = new WebException ("Server returned an error: " + status.StatusDescription,
 869                                 null, WebExceptionStatus.ProtocolError, ftpResponse);
 870                         return exc;
 871                 }
 872
 873                 // Here we could also get a server error, so be cautious
 874                 internal void SetTransferCompleted ()
 875                 {
 876                         if (InFinalState ())
 877                                 return;
 878
 879                         State = RequestState.Finished;
 880                         FtpStatus status = GetResponseStatus ();
 881                         ftpResponse.UpdateStatus (status);
 882                         if(!keepAlive)
 883                                 CloseConnection ();
 884                 }
 885
 886                 internal void OperationCompleted ()
 887                 {
 888                         if(!keepAlive)
 889                                 CloseConnection ();
 890                 }
 891
 892                 void SetCompleteWithError (Exception exc)
 893                 {
 894                         if (asyncResult != null) {
 895                                 asyncResult.SetCompleted (false, exc);
 896                         }
 897                 }
 898
 899                 Socket InitDataConnection ()
 900                 {
 901                         FtpStatus status;
 902
 903                         if (usePassive) {
 904                                 status = SendCommand (PassiveCommand);
 905                                 if (status.StatusCode != FtpStatusCode.EnteringPassive) {
 906                                         throw CreateExceptionFromResponse (status);
 907                                 }
 908
 909                                 return SetupPassiveConnection (status.StatusDescription);
 910                         }
 911
 912                         // Open a socket to listen the server's connection
 913                         Socket sock = new Socket (AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
 914                         try {
 915                                 sock.Bind (new IPEndPoint (localEndPoint.Address, 0));
 916                                 sock.Listen (1); // We only expect a connection from server
 917
 918                         } catch (SocketException e) {
 919                                 sock.Close ();
 920
 921                                 throw new WebException ("Couldn't open listening socket on client", e);
 922                         }
 923
 924                         IPEndPoint ep = (IPEndPoint) sock.LocalEndPoint;
 925                         string ipString = ep.Address.ToString ().Replace ('.', ',');
 926                         int h1 = ep.Port >> 8; // ep.Port / 256
 927                         int h2 = ep.Port % 256;
 928
 929                         string portParam = ipString + "," + h1 + "," + h2;
 930                         status = SendCommand (PortCommand, portParam);
 931
 932                         if (status.StatusCode != FtpStatusCode.CommandOK) {
 933                                 sock.Close ();
 934                                 throw (CreateExceptionFromResponse (status));
 935                         }
 936
 937                         return sock;
 938                 }
 939
 940                 void OpenDataConnection ()
 941                 {
 942                         FtpStatus status;
 943
 944                         Socket s = InitDataConnection ();
 945
 946                         // Handle content offset
 947                         if (offset > 0) {
 948                                 status = SendCommand (RestCommand, offset.ToString ());
 949                                 if (status.StatusCode != FtpStatusCode.FileCommandPending)
 950                                         throw CreateExceptionFromResponse (status);
 951                         }
 952
 953                         if (method != WebRequestMethods.Ftp.ListDirectory && method != WebRequestMethods.Ftp.ListDirectoryDetails &&
 954                             method != WebRequestMethods.Ftp.UploadFileWithUniqueName) {
 955                                 status = SendCommand (method, file_name);
 956                         } else {
 957                                 status = SendCommand (method);
 958                         }
 959
 960                         if (status.StatusCode != FtpStatusCode.OpeningData && status.StatusCode != FtpStatusCode.DataAlreadyOpen)
 961                                 throw CreateExceptionFromResponse (status);
 962
 963                         if (usePassive) {
 964                                 origDataStream = new NetworkStream (s, true);
 965                                 dataStream = origDataStream;
 966                                 if (EnableSsl)
 967                                         ChangeToSSLSocket (ref dataStream);
 968                         }
 969                         else {
 970
 971                                 // Active connection (use Socket.Blocking to true)
 972                                 Socket incoming = null;
 973                                 try {
 974                                         incoming = s.Accept ();
 975                                 }
 976                                 catch (SocketException) {
 977                                         s.Close ();
 978                                         if (incoming != null)
 979                                                 incoming.Close ();
 980
 981                                         throw new ProtocolViolationException ("Server commited a protocol violation.");
 982                                 }
 983
 984                                 s.Close ();
 985                                 origDataStream = new NetworkStream (s, true);
 986                                 dataStream = origDataStream;
 987                                 if (EnableSsl)
 988                                         ChangeToSSLSocket (ref dataStream);
 989                         }
 990
 991                         ftpResponse.UpdateStatus (status);
 992                 }
 993
 994                 void Authenticate ()
 995                 {
 996                         string username = null;
 997                         string password = null;
 998                         string domain = null;
 999
1000                         if (credentials != null) {
1001                                 username = credentials.UserName;
1002                                 password = credentials.Password;
1003                                 domain = credentials.Domain;
1004                         }
1005
1006                         if (username == null)
1007                                 username = "anonymous";
1008                         if (password == null)
1009                                 password = "@anonymous";
1010                         if (!string.IsNullOrEmpty (domain))
1011                                 username = domain + '\\' + username;
1012
1013                         // Connect to server and get banner message
1014                         FtpStatus status = GetResponseStatus ();
1015                         ftpResponse.BannerMessage = status.StatusDescription;
1016
1017                         if (EnableSsl) {
1018                                 InitiateSecureConnection (ref controlStream);
1019                                 controlReader = new StreamReader (controlStream, Encoding.ASCII);
1020                                 status = SendCommand ("PBSZ", "0");
1021                                 int st = (int) status.StatusCode;
1022                                 if (st < 200 || st >= 300)
1023                                         throw CreateExceptionFromResponse (status);
1024                                 // TODO: what if "PROT P" is denied by the server? What does MS do?
1025                                 status = SendCommand ("PROT", "P");
1026                                 st = (int) status.StatusCode;
1027                                 if (st < 200 || st >= 300)
1028                                         throw CreateExceptionFromResponse (status);
1029
1030                                 status = new FtpStatus (FtpStatusCode.SendUserCommand, "");
1031                         }
1032
1033                         if (status.StatusCode != FtpStatusCode.SendUserCommand)
1034                                 throw CreateExceptionFromResponse (status);
1035
1036                         status = SendCommand (UserCommand, username);
1037
1038                         switch (status.StatusCode) {
1039                         case FtpStatusCode.SendPasswordCommand:
1040                                 status = SendCommand (PasswordCommand, password);
1041                                 if (status.StatusCode != FtpStatusCode.LoggedInProceed)
1042                                         throw CreateExceptionFromResponse (status);
1043                                 break;
1044                         case FtpStatusCode.LoggedInProceed:
1045                                 break;
1046                         default:
1047                                 throw CreateExceptionFromResponse (status);
1048                         }
1049
1050                         ftpResponse.WelcomeMessage = status.StatusDescription;
1051                         ftpResponse.UpdateStatus (status);
1052                 }
1053
1054                 FtpStatus SendCommand (string command, params string [] parameters) {
1055                         return SendCommand (true, command, parameters);
1056                 }
1057
1058                 FtpStatus SendCommand (bool waitResponse, string command, params string [] parameters)
1059                 {
1060                         byte [] cmd;
1061                         string commandString = command;
1062                         if (parameters.Length > 0)
1063                                 commandString += " " + String.Join (" ", parameters);
1064
1065                         commandString += EOL;
1066                         cmd = Encoding.ASCII.GetBytes (commandString);
1067                         try {
1068                                 controlStream.Write (cmd, 0, cmd.Length);
1069                         } catch (IOException) {
1070                                 //controlStream.Close ();
1071                                 return new FtpStatus(FtpStatusCode.ServiceNotAvailable, "Write failed");
1072                         }
1073
1074                         if(!waitResponse)
1075                                 return null;
1076
1077                         FtpStatus result = GetResponseStatus ();
1078                         if (ftpResponse != null)
1079                                 ftpResponse.UpdateStatus (result);
1080                         return result;
1081                 }
1082
1083                 internal static FtpStatus ServiceNotAvailable ()
1084                 {
1085                         return new FtpStatus (FtpStatusCode.ServiceNotAvailable, Locale.GetText ("Invalid response from server"));
1086                 }
1087
1088                 internal FtpStatus GetResponseStatus ()
1089                 {
1090                         while (true) {
1091                                 string response = null;
1092
1093                                 try {
1094                                         response = controlReader.ReadLine ();
1095                                 } catch (IOException) {
1096                                 }
1097
1098                                 if (response == null || response.Length < 3)
1099                                         return ServiceNotAvailable ();
1100
1101                                 int code;
1102                                 if (!Int32.TryParse (response.Substring (0, 3), out code))
1103                                         return ServiceNotAvailable ();
1104
1105                                 if (response.Length > 3 && response [3] == '-'){
1106                                         string line = null;
1107                                         string find = code.ToString() + ' ';
1108                                         while (true){
1109                                                 line = null;
1110                                                 try {
1111                                                         line = controlReader.ReadLine();
1112                                                 } catch (IOException) {
1113                                                 }
1114                                                 if (line == null)
1115                                                         return ServiceNotAvailable ();
1116
1117                                                 response += Environment.NewLine + line;
1118
1119                                                 if (line.StartsWith(find, StringComparison.Ordinal))
1120                                                         break;
1121                                         }
1122                                 }
1123                                 return new FtpStatus ((FtpStatusCode) code, response);
1124                         }
1125                 }
1126
1127                 private void InitiateSecureConnection (ref Stream stream) {
1128                         FtpStatus status = SendCommand (AuthCommand, "TLS");
1129                         if (status.StatusCode != FtpStatusCode.ServerWantsSecureSession)
1130                                 throw CreateExceptionFromResponse (status);
1131
1132                         ChangeToSSLSocket (ref stream);
1133                 }
1134
1135 #if SECURITY_DEP
1136                 RemoteCertificateValidationCallback callback = delegate (object sender,
1137                                                                          X509Certificate certificate,
1138                                                                          X509Chain chain,
1139                                                                          SslPolicyErrors sslPolicyErrors) {
1140                         // honor any exciting callback defined on ServicePointManager
1141                         if (ServicePointManager.ServerCertificateValidationCallback != null)
1142                                 return ServicePointManager.ServerCertificateValidationCallback (sender, certificate, chain, sslPolicyErrors);
1143                         // otherwise provide our own
1144                         if (sslPolicyErrors != SslPolicyErrors.None)
1145                                 throw new InvalidOperationException ("SSL authentication error: " + sslPolicyErrors);
1146                         return true;
1147                         };
1148 #endif
1149
1150                 internal bool ChangeToSSLSocket (ref Stream stream) {
1151 #if TARGET_JVM
1152                         stream.ChangeToSSLSocket ();
1153                         return true;
1154 #elif SECURITY_DEP
1155                         SslStream sslStream = new SslStream (stream, true, callback, null);
1156                         //sslStream.AuthenticateAsClient (Host, this.ClientCertificates, SslProtocols.Default, false);
1157                         //TODO: client certificates
1158                         sslStream.AuthenticateAsClient (requestUri.Host, null, SslProtocols.Default, false);
1159                         stream = sslStream;
1160                         return true;
1161 #else
1162                         throw new NotImplementedException ();
1163 #endif
1164                 }
1165
1166                 bool InFinalState () {
1167                         return (State == RequestState.Aborted || State == RequestState.Error || State == RequestState.Finished);
1168                 }
1169
1170                 bool InProgress () {
1171                         return (State != RequestState.Before && !InFinalState ());
1172                 }
1173
1174                 internal void CheckIfAborted () {
1175                         if (State == RequestState.Aborted)
1176                                 throw new WebException ("Request aborted", WebExceptionStatus.RequestCanceled);
1177                 }
1178
1179                 void CheckFinalState () {
1180                         if (InFinalState ())
1181                                 throw new InvalidOperationException ("Cannot change final state");
1182                 }
1183         }
1184 }
1185
1186 #endif
1187