mcs/class/System/System.Net/HttpWebRequest.cs

   1 //
   2 // System.Net.HttpWebRequest
   3 //
   4 // Authors:
   5 //      Lawrence Pit (loz@cable.a2000.nl)
   6 //      Gonzalo Paniagua Javier (gonzalo@ximian.com)
   7 //
   8 // (c) 2002 Lawrence Pit
   9 // (c) 2003 Ximian, Inc. (http://www.ximian.com)
  10 // (c) 2004 Novell, Inc. (http://www.novell.com)
  11 //
  12
  13 //
  14 // Permission is hereby granted, free of charge, to any person obtaining
  15 // a copy of this software and associated documentation files (the
  16 // "Software"), to deal in the Software without restriction, including
  17 // without limitation the rights to use, copy, modify, merge, publish,
  18 // distribute, sublicense, and/or sell copies of the Software, and to
  19 // permit persons to whom the Software is furnished to do so, subject to
  20 // the following conditions:
  21 //
  22 // The above copyright notice and this permission notice shall be
  23 // included in all copies or substantial portions of the Software.
  24 //
  25 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  26 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  27 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  28 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  29 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  30 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  31 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  32 //
  33
  34 using System;
  35 using System.Collections;
  36 using System.Configuration;
  37 using System.Globalization;
  38 using System.IO;
  39 using System.Net.Cache;
  40 using System.Net.Sockets;
  41 using System.Runtime.Remoting.Messaging;
  42 using System.Runtime.Serialization;
  43 using System.Security.Cryptography.X509Certificates;
  44 using System.Text;
  45 using System.Threading;
  46
  47 namespace System.Net
  48 {
  49 #if MOONLIGHT
  50         internal class HttpWebRequest : WebRequest, ISerializable {
  51 #else
  52         [Serializable]
  53         public class HttpWebRequest : WebRequest, ISerializable {
  54 #endif
  55                 Uri requestUri;
  56                 Uri actualUri;
  57                 bool hostChanged;
  58                 bool allowAutoRedirect = true;
  59                 bool allowBuffering = true;
  60                 X509CertificateCollection certificates;
  61                 string connectionGroup;
  62                 long contentLength = -1;
  63                 HttpContinueDelegate continueDelegate;
  64                 CookieContainer cookieContainer;
  65                 ICredentials credentials;
  66                 bool haveResponse;
  67                 bool haveRequest;
  68                 bool requestSent;
  69                 WebHeaderCollection webHeaders = new WebHeaderCollection (true);
  70                 bool keepAlive = true;
  71                 int maxAutoRedirect = 50;
  72                 string mediaType = String.Empty;
  73                 string method = "GET";
  74                 string initialMethod = "GET";
  75                 bool pipelined = true;
  76                 bool preAuthenticate;
  77                 bool usedPreAuth;
  78                 Version version = HttpVersion.Version11;
  79                 bool force_version;
  80                 Version actualVersion;
  81                 IWebProxy proxy;
  82                 bool sendChunked;
  83                 ServicePoint servicePoint;
  84                 int timeout = 100000;
  85
  86                 WebConnectionStream writeStream;
  87                 HttpWebResponse webResponse;
  88                 WebAsyncResult asyncWrite;
  89                 WebAsyncResult asyncRead;
  90                 EventHandler abortHandler;
  91                 int aborted;
  92                 bool gotRequestStream;
  93                 int redirects;
  94                 bool expectContinue;
  95                 bool authCompleted;
  96                 byte[] bodyBuffer;
  97                 int bodyBufferLength;
  98                 bool getResponseCalled;
  99                 Exception saved_exc;
 100                 object locker = new object ();
 101                 bool finished_reading;
 102                 internal WebConnection WebConnection;
 103                 DecompressionMethods auto_decomp;
 104                 int maxResponseHeadersLength;
 105                 static int defaultMaxResponseHeadersLength;
 106                 int readWriteTimeout = 300000; // ms
 107
 108                 enum NtlmAuthState {
 109                         None,
 110                         Challenge,
 111                         Response
 112                 }
 113                 NtlmAuthState ntlm_auth_state;
 114                 string host;
 115
 116                 // Constructors
 117                 static HttpWebRequest ()
 118                 {
 119                         defaultMaxResponseHeadersLength = 64 * 1024;
 120 #if !NET_2_1
 121                         NetConfig config = ConfigurationSettings.GetConfig ("system.net/settings") as NetConfig;
 122                         if (config != null) {
 123                                 int x = config.MaxResponseHeadersLength;
 124                                 if (x != -1)
 125                                         x *= 64;
 126
 127                                 defaultMaxResponseHeadersLength = x;
 128                         }
 129 #endif
 130                 }
 131
 132 #if NET_2_1
 133                 public
 134 #else
 135                 internal
 136 #endif
 137                 HttpWebRequest (Uri uri)
 138                 {
 139                         this.requestUri = uri;
 140                         this.actualUri = uri;
 141                         this.proxy = GlobalProxySelection.Select;
 142                 }
 143
 144                 [Obsolete ("Serialization is obsoleted for this type", false)]
 145                 protected HttpWebRequest (SerializationInfo serializationInfo, StreamingContext streamingContext)
 146                 {
 147                         SerializationInfo info = serializationInfo;
 148
 149                         requestUri = (Uri) info.GetValue ("requestUri", typeof (Uri));
 150                         actualUri = (Uri) info.GetValue ("actualUri", typeof (Uri));
 151                         allowAutoRedirect = info.GetBoolean ("allowAutoRedirect");
 152                         allowBuffering = info.GetBoolean ("allowBuffering");
 153                         certificates = (X509CertificateCollection) info.GetValue ("certificates", typeof (X509CertificateCollection));
 154                         connectionGroup = info.GetString ("connectionGroup");
 155                         contentLength = info.GetInt64 ("contentLength");
 156                         webHeaders = (WebHeaderCollection) info.GetValue ("webHeaders", typeof (WebHeaderCollection));
 157                         keepAlive = info.GetBoolean ("keepAlive");
 158                         maxAutoRedirect = info.GetInt32 ("maxAutoRedirect");
 159                         mediaType = info.GetString ("mediaType");
 160                         method = info.GetString ("method");
 161                         initialMethod = info.GetString ("initialMethod");
 162                         pipelined = info.GetBoolean ("pipelined");
 163                         version = (Version) info.GetValue ("version", typeof (Version));
 164                         proxy = (IWebProxy) info.GetValue ("proxy", typeof (IWebProxy));
 165                         sendChunked = info.GetBoolean ("sendChunked");
 166                         timeout = info.GetInt32 ("timeout");
 167                         redirects = info.GetInt32 ("redirects");
 168                         host = info.GetString ("host");
 169                 }
 170
 171                 // Properties
 172
 173                 public string Accept {
 174                         get { return webHeaders ["Accept"]; }
 175                         set {
 176                                 CheckRequestStarted ();
 177                                 webHeaders.RemoveAndAdd ("Accept", value);
 178                         }
 179                 }
 180
 181                 public Uri Address {
 182                         get { return actualUri; }
 183                         internal set { actualUri = value; } // Used by Ftp+proxy
 184                 }
 185
 186                 public bool AllowAutoRedirect {
 187                         get { return allowAutoRedirect; }
 188                         set { this.allowAutoRedirect = value; }
 189                 }
 190
 191                 public bool AllowWriteStreamBuffering {
 192                         get { return allowBuffering; }
 193                         set { allowBuffering = value; }
 194                 }
 195
 196                 static Exception GetMustImplement ()
 197                 {
 198                         return new NotImplementedException ();
 199                 }
 200
 201                 public DecompressionMethods AutomaticDecompression
 202                 {
 203                         get {
 204                                 return auto_decomp;
 205                         }
 206                         set {
 207                                 CheckRequestStarted ();
 208                                 auto_decomp = value;
 209                         }
 210                 }
 211
 212                 internal bool InternalAllowBuffering {
 213                         get {
 214                                 return (allowBuffering && (method != "HEAD" && method != "GET" &&
 215                                                         method != "MKCOL" && method != "CONNECT" &&
 216                                                         method != "TRACE"));
 217                         }
 218                 }
 219
 220                 public X509CertificateCollection ClientCertificates {
 221                         get {
 222                                 if (certificates == null)
 223                                         certificates = new X509CertificateCollection ();
 224
 225                                 return certificates;
 226                         }
 227                         [MonoTODO]
 228                         set {
 229                                 throw GetMustImplement ();
 230                         }
 231                 }
 232
 233                 public string Connection {
 234                         get { return webHeaders ["Connection"]; }
 235                         set {
 236                                 CheckRequestStarted ();
 237
 238                                 if (string.IsNullOrEmpty (value)) {
 239                                         webHeaders.RemoveInternal ("Connection");
 240                                         return;
 241                                 }
 242
 243                                 string val = value.ToLowerInvariant ();
 244                                 if (val.Contains ("keep-alive") || val.Contains ("close"))
 245                                         throw new ArgumentException ("Keep-Alive and Close may not be set with this property");
 246
 247                                 if (keepAlive)
 248                                         value = value + ", Keep-Alive";
 249
 250                                 webHeaders.RemoveAndAdd ("Connection", value);
 251                         }
 252                 }
 253
 254                 public override string ConnectionGroupName {
 255                         get { return connectionGroup; }
 256                         set { connectionGroup = value; }
 257                 }
 258
 259                 public override long ContentLength {
 260                         get { return contentLength; }
 261                         set {
 262                                 CheckRequestStarted ();
 263                                 if (value < 0)
 264                                         throw new ArgumentOutOfRangeException ("value", "Content-Length must be >= 0");
 265
 266                                 contentLength = value;
 267                         }
 268                 }
 269
 270                 internal long InternalContentLength {
 271                         set { contentLength = value; }
 272                 }
 273
 274                 public override string ContentType {
 275                         get { return webHeaders ["Content-Type"]; }
 276                         set {
 277                                 if (value == null || value.Trim().Length == 0) {
 278                                         webHeaders.RemoveInternal ("Content-Type");
 279                                         return;
 280                                 }
 281                                 webHeaders.RemoveAndAdd ("Content-Type", value);
 282                         }
 283                 }
 284
 285                 public HttpContinueDelegate ContinueDelegate {
 286                         get { return continueDelegate; }
 287                         set { continueDelegate = value; }
 288                 }
 289
 290                 public CookieContainer CookieContainer {
 291                         get { return cookieContainer; }
 292                         set { cookieContainer = value; }
 293                 }
 294
 295                 public override ICredentials Credentials {
 296                         get { return credentials; }
 297                         set { credentials = value; }
 298                 }
 299 #if NET_4_0
 300                 public DateTime Date {
 301                         get {
 302                                 string date = webHeaders ["Date"];
 303                                 if (date == null)
 304                                         return DateTime.MinValue;
 305                                 return DateTime.ParseExact (date, "r", CultureInfo.InvariantCulture).ToLocalTime ();
 306                         }
 307                         set {
 308                                 if (value == null) {
 309                                         webHeaders.RemoveInternal ("Date");
 310                                 } else {
 311                                         webHeaders.RemoveAndAdd ("Date", value.ToUniversalTime ().ToString ("r", CultureInfo.InvariantCulture));
 312                                 }
 313                         }
 314                 }
 315 #endif
 316                 [MonoTODO]
 317                 public static new RequestCachePolicy DefaultCachePolicy
 318                 {
 319                         get {
 320                                 throw GetMustImplement ();
 321                         }
 322                         set {
 323                                 throw GetMustImplement ();
 324                         }
 325                 }
 326
 327                 [MonoTODO]
 328                 public static int DefaultMaximumErrorResponseLength
 329                 {
 330                         get {
 331                                 throw GetMustImplement ();
 332                         }
 333                         set {
 334                                 throw GetMustImplement ();
 335                         }
 336                 }
 337
 338                 public string Expect {
 339                         get { return webHeaders ["Expect"]; }
 340                         set {
 341                                 CheckRequestStarted ();
 342                                 string val = value;
 343                                 if (val != null)
 344                                         val = val.Trim ().ToLower ();
 345
 346                                 if (val == null || val.Length == 0) {
 347                                         webHeaders.RemoveInternal ("Expect");
 348                                         return;
 349                                 }
 350
 351                                 if (val == "100-continue")
 352                                         throw new ArgumentException ("100-Continue cannot be set with this property.",
 353                                                                      "value");
 354                                 webHeaders.RemoveAndAdd ("Expect", value);
 355                         }
 356                 }
 357
 358                 public bool HaveResponse {
 359                         get { return haveResponse; }
 360                 }
 361
 362                 public override WebHeaderCollection Headers {
 363                         get { return webHeaders; }
 364                         set {
 365                                 CheckRequestStarted ();
 366                                 WebHeaderCollection newHeaders = new WebHeaderCollection (true);
 367                                 int count = value.Count;
 368                                 for (int i = 0; i < count; i++)
 369                                         newHeaders.Add (value.GetKey (i), value.Get (i));
 370
 371                                 webHeaders = newHeaders;
 372                         }
 373                 }
 374 #if NET_4_0
 375                 public
 376 #else
 377                 internal
 378 #endif
 379                 string Host {
 380                         get {
 381                                 if (host == null)
 382                                         return actualUri.Authority;
 383                                 return host;
 384                         }
 385                         set {
 386                                 if (value == null)
 387                                         throw new ArgumentNullException ("value");
 388
 389                                 if (!CheckValidHost (actualUri.Scheme, value))
 390                                         throw new ArgumentException ("Invalid host: " + value);
 391
 392                                 host = value;
 393                         }
 394                 }
 395
 396                 static bool CheckValidHost (string scheme, string val)
 397                 {
 398                         if (val == null)
 399                                 throw new ArgumentNullException ("value");
 400
 401                         if (val.Length == 0)
 402                                 return false;
 403
 404                         if (val [0] == '.')
 405                                 return false;
 406
 407                         int idx = val.IndexOf ('/');
 408                         if (idx >= 0)
 409                                 return false;
 410
 411                         string u = scheme + "://" + val + "/";
 412                         return Uri.IsWellFormedUriString (u, UriKind.Absolute);
 413                 }
 414
 415                 public DateTime IfModifiedSince {
 416                         get {
 417                                 string str = webHeaders ["If-Modified-Since"];
 418                                 if (str == null)
 419                                         return DateTime.Now;
 420                                 try {
 421                                         return MonoHttpDate.Parse (str);
 422                                 } catch (Exception) {
 423                                         return DateTime.Now;
 424                                 }
 425                         }
 426                         set {
 427                                 CheckRequestStarted ();
 428                                 // rfc-1123 pattern
 429                                 webHeaders.SetInternal ("If-Modified-Since",
 430                                         value.ToUniversalTime ().ToString ("r", null));
 431                                 // TODO: check last param when using different locale
 432                         }
 433                 }
 434
 435                 public bool KeepAlive {
 436                         get {
 437                                 return keepAlive;
 438                         }
 439                         set {
 440                                 keepAlive = value;
 441                         }
 442                 }
 443
 444                 public int MaximumAutomaticRedirections {
 445                         get { return maxAutoRedirect; }
 446                         set {
 447                                 if (value <= 0)
 448                                         throw new ArgumentException ("Must be > 0", "value");
 449
 450                                 maxAutoRedirect = value;
 451                         }
 452                 }
 453
 454                 [MonoTODO ("Use this")]
 455                 public int MaximumResponseHeadersLength {
 456                         get { return maxResponseHeadersLength; }
 457                         set { maxResponseHeadersLength = value; }
 458                 }
 459
 460                 [MonoTODO ("Use this")]
 461                 public static int DefaultMaximumResponseHeadersLength {
 462                         get { return defaultMaxResponseHeadersLength; }
 463                         set { defaultMaxResponseHeadersLength = value; }
 464                 }
 465
 466                 public  int ReadWriteTimeout {
 467                         get { return readWriteTimeout; }
 468                         set {
 469                                 if (requestSent)
 470                                         throw new InvalidOperationException ("The request has already been sent.");
 471
 472                                 if (value < -1)
 473                                         throw new ArgumentOutOfRangeException ("value", "Must be >= -1");
 474
 475                                 readWriteTimeout = value;
 476                         }
 477                 }
 478
 479                 public string MediaType {
 480                         get { return mediaType; }
 481                         set {
 482                                 mediaType = value;
 483                         }
 484                 }
 485
 486                 public override string Method {
 487                         get { return this.method; }
 488                         set {
 489                                 if (value == null || value.Trim () == "")
 490                                         throw new ArgumentException ("not a valid method");
 491
 492                                 method = value.ToUpperInvariant ();
 493                                 if (method != "HEAD" && method != "GET" && method != "POST" && method != "PUT" &&
 494                                         method != "DELETE" && method != "CONNECT" && method != "TRACE" &&
 495                                         method != "MKCOL") {
 496                                         method = value;
 497                                 }
 498                         }
 499                 }
 500
 501                 public bool Pipelined {
 502                         get { return pipelined; }
 503                         set { pipelined = value; }
 504                 }
 505
 506                 public override bool PreAuthenticate {
 507                         get { return preAuthenticate; }
 508                         set { preAuthenticate = value; }
 509                 }
 510
 511                 public Version ProtocolVersion {
 512                         get { return version; }
 513                         set {
 514                                 if (value != HttpVersion.Version10 && value != HttpVersion.Version11)
 515                                         throw new ArgumentException ("value");
 516
 517                                 force_version = true;
 518                                 version = value;
 519                         }
 520                 }
 521
 522                 public override IWebProxy Proxy {
 523                         get { return proxy; }
 524                         set {
 525                                 CheckRequestStarted ();
 526                                 proxy = value;
 527                                 servicePoint = null; // we may need a new one
 528                         }
 529                 }
 530
 531                 public string Referer {
 532                         get { return webHeaders ["Referer"]; }
 533                         set {
 534                                 CheckRequestStarted ();
 535                                 if (value == null || value.Trim().Length == 0) {
 536                                         webHeaders.RemoveInternal ("Referer");
 537                                         return;
 538                                 }
 539                                 webHeaders.SetInternal ("Referer", value);
 540                         }
 541                 }
 542
 543                 public override Uri RequestUri {
 544                         get { return requestUri; }
 545                 }
 546
 547                 public bool SendChunked {
 548                         get { return sendChunked; }
 549                         set {
 550                                 CheckRequestStarted ();
 551                                 sendChunked = value;
 552                         }
 553                 }
 554
 555                 public ServicePoint ServicePoint {
 556                         get { return GetServicePoint (); }
 557                 }
 558
 559                 public override int Timeout {
 560                         get { return timeout; }
 561                         set {
 562                                 if (value < -1)
 563                                         throw new ArgumentOutOfRangeException ("value");
 564
 565                                 timeout = value;
 566                         }
 567                 }
 568
 569                 public string TransferEncoding {
 570                         get { return webHeaders ["Transfer-Encoding"]; }
 571                         set {
 572                                 CheckRequestStarted ();
 573                                 string val = value;
 574                                 if (val != null)
 575                                         val = val.Trim ().ToLower ();
 576
 577                                 if (val == null || val.Length == 0) {
 578                                         webHeaders.RemoveInternal ("Transfer-Encoding");
 579                                         return;
 580                                 }
 581
 582                                 if (val == "chunked")
 583                                         throw new ArgumentException ("Chunked encoding must be set with the SendChunked property");
 584
 585                                 if (!sendChunked)
 586                                         throw new ArgumentException ("SendChunked must be True", "value");
 587
 588                                 webHeaders.RemoveAndAdd ("Transfer-Encoding", value);
 589                         }
 590                 }
 591
 592                 public override bool UseDefaultCredentials
 593                 {
 594                         get { return CredentialCache.DefaultCredentials == Credentials; }
 595                         set { Credentials = value ? CredentialCache.DefaultCredentials : null; }
 596                 }
 597
 598                 public string UserAgent {
 599                         get { return webHeaders ["User-Agent"]; }
 600                         set { webHeaders.SetInternal ("User-Agent", value); }
 601                 }
 602
 603                 bool unsafe_auth_blah;
 604                 public bool UnsafeAuthenticatedConnectionSharing
 605                 {
 606                         get { return unsafe_auth_blah; }
 607                         set { unsafe_auth_blah = value; }
 608                 }
 609
 610                 internal bool GotRequestStream {
 611                         get { return gotRequestStream; }
 612                 }
 613
 614                 internal bool ExpectContinue {
 615                         get { return expectContinue; }
 616                         set { expectContinue = value; }
 617                 }
 618
 619                 internal Uri AuthUri {
 620                         get { return actualUri; }
 621                 }
 622
 623                 internal bool ProxyQuery {
 624                         get { return servicePoint.UsesProxy && !servicePoint.UseConnect; }
 625                 }
 626
 627                 // Methods
 628
 629                 internal ServicePoint GetServicePoint ()
 630                 {
 631                         lock (locker) {
 632                                 if (hostChanged || servicePoint == null) {
 633                                         servicePoint = ServicePointManager.FindServicePoint (actualUri, proxy);
 634                                         hostChanged = false;
 635                                 }
 636                         }
 637
 638                         return servicePoint;
 639                 }
 640
 641                 public void AddRange (int range)
 642                 {
 643                         AddRange ("bytes", (long) range);
 644                 }
 645
 646                 public void AddRange (int from, int to)
 647                 {
 648                         AddRange ("bytes", (long) from, (long) to);
 649                 }
 650
 651                 public void AddRange (string rangeSpecifier, int range)
 652                 {
 653                         AddRange (rangeSpecifier, (long) range);
 654                 }
 655
 656                 public void AddRange (string rangeSpecifier, int from, int to)
 657                 {
 658                         AddRange (rangeSpecifier, (long) from, (long) to);
 659                 }
 660 #if NET_4_0
 661                 public
 662 #else
 663                 internal
 664 #endif
 665                 void AddRange (long range)
 666                 {
 667                         AddRange ("bytes", (long) range);
 668                 }
 669
 670 #if NET_4_0
 671                 public
 672 #else
 673                 internal
 674 #endif
 675                 void AddRange (long from, long to)
 676                 {
 677                         AddRange ("bytes", from, to);
 678                 }
 679
 680 #if NET_4_0
 681                 public
 682 #else
 683                 internal
 684 #endif
 685                 void AddRange (string rangeSpecifier, long range)
 686                 {
 687                         if (rangeSpecifier == null)
 688                                 throw new ArgumentNullException ("rangeSpecifier");
 689                         if (!WebHeaderCollection.IsHeaderValue (rangeSpecifier))
 690                                 throw new ArgumentException ("Invalid range specifier", "rangeSpecifier");
 691
 692                         string r = webHeaders ["Range"];
 693                         if (r == null)
 694                                 r = rangeSpecifier + "=";
 695                         else {
 696                                 string old_specifier = r.Substring (0, r.IndexOf ('='));
 697                                 if (String.Compare (old_specifier, rangeSpecifier, StringComparison.OrdinalIgnoreCase) != 0)
 698                                         throw new InvalidOperationException ("A different range specifier is already in use");
 699                                 r += ",";
 700                         }
 701
 702                         string n = range.ToString (CultureInfo.InvariantCulture);
 703                         if (range < 0)
 704                                 r = r + "0" + n;
 705                         else
 706                                 r = r + n + "-";
 707                         webHeaders.RemoveAndAdd ("Range", r);
 708                 }
 709
 710 #if NET_4_0
 711                 public
 712 #else
 713                 internal
 714 #endif
 715                 void AddRange (string rangeSpecifier, long from, long to)
 716                 {
 717                         if (rangeSpecifier == null)
 718                                 throw new ArgumentNullException ("rangeSpecifier");
 719                         if (!WebHeaderCollection.IsHeaderValue (rangeSpecifier))
 720                                 throw new ArgumentException ("Invalid range specifier", "rangeSpecifier");
 721                         if (from > to || from < 0)
 722                                 throw new ArgumentOutOfRangeException ("from");
 723                         if (to < 0)
 724                                 throw new ArgumentOutOfRangeException ("to");
 725
 726                         string r = webHeaders ["Range"];
 727                         if (r == null)
 728                                 r = rangeSpecifier + "=";
 729                         else
 730                                 r += ",";
 731
 732                         r = String.Format ("{0}{1}-{2}", r, from, to);
 733                         webHeaders.RemoveAndAdd ("Range", r);
 734                 }
 735
 736
 737                 public override IAsyncResult BeginGetRequestStream (AsyncCallback callback, object state)
 738                 {
 739                         if (Aborted)
 740                                 throw new WebException ("The request was canceled.", WebExceptionStatus.RequestCanceled);
 741
 742                         bool send = !(method == "GET" || method == "CONNECT" || method == "HEAD" ||
 743                                         method == "TRACE");
 744                         if (method == null || !send)
 745                                 throw new ProtocolViolationException ("Cannot send data when method is: " + method);
 746
 747                         if (contentLength == -1 && !sendChunked && !allowBuffering && KeepAlive)
 748                                 throw new ProtocolViolationException ("Content-Length not set");
 749
 750                         string transferEncoding = TransferEncoding;
 751                         if (!sendChunked && transferEncoding != null && transferEncoding.Trim () != "")
 752                                 throw new ProtocolViolationException ("SendChunked should be true.");
 753
 754                         lock (locker)
 755                         {
 756                                 if (asyncWrite != null) {
 757                                         throw new InvalidOperationException ("Cannot re-call start of asynchronous " +
 758                                                                 "method while a previous call is still in progress.");
 759                                 }
 760
 761                                 asyncWrite = new WebAsyncResult (this, callback, state);
 762                                 initialMethod = method;
 763                                 if (haveRequest) {
 764                                         if (writeStream != null) {
 765                                                 asyncWrite.SetCompleted (true, writeStream);
 766                                                 asyncWrite.DoCallback ();
 767                                                 return asyncWrite;
 768                                         }
 769                                 }
 770
 771                                 gotRequestStream = true;
 772                                 WebAsyncResult result = asyncWrite;
 773                                 if (!requestSent) {
 774                                         requestSent = true;
 775                                         redirects = 0;
 776                                         servicePoint = GetServicePoint ();
 777                                         abortHandler = servicePoint.SendRequest (this, connectionGroup);
 778                                 }
 779                                 return result;
 780                         }
 781                 }
 782
 783                 public override Stream EndGetRequestStream (IAsyncResult asyncResult)
 784                 {
 785                         if (asyncResult == null)
 786                                 throw new ArgumentNullException ("asyncResult");
 787
 788                         WebAsyncResult result = asyncResult as WebAsyncResult;
 789                         if (result == null)
 790                                 throw new ArgumentException ("Invalid IAsyncResult");
 791
 792                         asyncWrite = result;
 793                         result.WaitUntilComplete ();
 794
 795                         Exception e = result.Exception;
 796                         if (e != null)
 797                                 throw e;
 798
 799                         return result.WriteStream;
 800                 }
 801
 802                 public override Stream GetRequestStream()
 803                 {
 804                         IAsyncResult asyncResult = asyncWrite;
 805                         if (asyncResult == null) {
 806                                 asyncResult = BeginGetRequestStream (null, null);
 807                                 asyncWrite = (WebAsyncResult) asyncResult;
 808                         }
 809
 810                         if (!asyncResult.IsCompleted && !asyncResult.AsyncWaitHandle.WaitOne (timeout, false)) {
 811                                 Abort ();
 812                                 throw new WebException ("The request timed out", WebExceptionStatus.Timeout);
 813                         }
 814
 815                         return EndGetRequestStream (asyncResult);
 816                 }
 817
 818                 void CheckIfForceWrite ()
 819                 {
 820                         if (writeStream == null || writeStream.RequestWritten || (contentLength < 0 && writeStream.CanWrite == true) || !InternalAllowBuffering)
 821                                 return;
 822
 823                         // This will write the POST/PUT if the write stream already has the expected
 824                         // amount of bytes in it (ContentLength) (bug #77753) or if the write stream
 825                         // contains data and it has been closed already (xamarin bug #1512).
 826
 827                         if (writeStream.WriteBufferLength == contentLength || (contentLength == -1 && writeStream.CanWrite == false))
 828                                 writeStream.WriteRequest ();
 829                 }
 830
 831                 public override IAsyncResult BeginGetResponse (AsyncCallback callback, object state)
 832                 {
 833                         if (Aborted)
 834                                 throw new WebException ("The request was canceled.", WebExceptionStatus.RequestCanceled);
 835
 836                         if (method == null)
 837                                 throw new ProtocolViolationException ("Method is null.");
 838
 839                         string transferEncoding = TransferEncoding;
 840                         if (!sendChunked && transferEncoding != null && transferEncoding.Trim () != "")
 841                                 throw new ProtocolViolationException ("SendChunked should be true.");
 842
 843                         Monitor.Enter (locker);
 844                         getResponseCalled = true;
 845                         if (asyncRead != null && !haveResponse) {
 846                                 Monitor.Exit (locker);
 847                                 throw new InvalidOperationException ("Cannot re-call start of asynchronous " +
 848                                                         "method while a previous call is still in progress.");
 849                         }
 850
 851                         CheckIfForceWrite ();
 852                         asyncRead = new WebAsyncResult (this, callback, state);
 853                         WebAsyncResult aread = asyncRead;
 854                         initialMethod = method;
 855                         if (haveResponse) {
 856                                 Exception saved = saved_exc;
 857                                 if (webResponse != null) {
 858                                         Monitor.Exit (locker);
 859                                         if (saved == null) {
 860                                                 aread.SetCompleted (true, webResponse);
 861                                         } else {
 862                                                 aread.SetCompleted (true, saved);
 863                                         }
 864                                         aread.DoCallback ();
 865                                         return aread;
 866                                 } else if (saved != null) {
 867                                         Monitor.Exit (locker);
 868                                         aread.SetCompleted (true, saved);
 869                                         aread.DoCallback ();
 870                                         return aread;
 871                                 }
 872                         }
 873
 874                         if (!requestSent) {
 875                                 requestSent = true;
 876                                 redirects = 0;
 877                                 servicePoint = GetServicePoint ();
 878                                 abortHandler = servicePoint.SendRequest (this, connectionGroup);
 879                         }
 880
 881                         Monitor.Exit (locker);
 882                         return aread;
 883                 }
 884
 885                 public override WebResponse EndGetResponse (IAsyncResult asyncResult)
 886                 {
 887                         if (asyncResult == null)
 888                                 throw new ArgumentNullException ("asyncResult");
 889
 890                         WebAsyncResult result = asyncResult as WebAsyncResult;
 891                         if (result == null)
 892                                 throw new ArgumentException ("Invalid IAsyncResult", "asyncResult");
 893
 894                         if (!result.WaitUntilComplete (timeout, false)) {
 895                                 Abort ();
 896                                 throw new WebException("The request timed out", WebExceptionStatus.Timeout);
 897                         }
 898
 899                         if (result.GotException)
 900                                 throw result.Exception;
 901
 902                         return result.Response;
 903                 }
 904
 905                 public override WebResponse GetResponse()
 906                 {
 907                         WebAsyncResult result = (WebAsyncResult) BeginGetResponse (null, null);
 908                         return EndGetResponse (result);
 909                 }
 910
 911                 internal bool FinishedReading {
 912                         get { return finished_reading; }
 913                         set { finished_reading = value; }
 914                 }
 915
 916                 internal bool Aborted {
 917                         get { return Interlocked.CompareExchange (ref aborted, 0, 0) == 1; }
 918                 }
 919
 920                 public override void Abort ()
 921                 {
 922                         if (Interlocked.CompareExchange (ref aborted, 1, 0) == 1)
 923                                 return;
 924
 925                         if (haveResponse && finished_reading)
 926                                 return;
 927
 928                         haveResponse = true;
 929                         if (abortHandler != null) {
 930                                 try {
 931                                         abortHandler (this, EventArgs.Empty);
 932                                 } catch (Exception) {}
 933                                 abortHandler = null;
 934                         }
 935
 936                         if (asyncWrite != null) {
 937                                 WebAsyncResult r = asyncWrite;
 938                                 if (!r.IsCompleted) {
 939                                         try {
 940                                                 WebException wexc = new WebException ("Aborted.", WebExceptionStatus.RequestCanceled);
 941                                                 r.SetCompleted (false, wexc);
 942                                                 r.DoCallback ();
 943                                         } catch {}
 944                                 }
 945                                 asyncWrite = null;
 946                         }
 947
 948                         if (asyncRead != null) {
 949                                 WebAsyncResult r = asyncRead;
 950                                 if (!r.IsCompleted) {
 951                                         try {
 952                                                 WebException wexc = new WebException ("Aborted.", WebExceptionStatus.RequestCanceled);
 953                                                 r.SetCompleted (false, wexc);
 954                                                 r.DoCallback ();
 955                                         } catch {}
 956                                 }
 957                                 asyncRead = null;
 958                         }
 959
 960                         if (writeStream != null) {
 961                                 try {
 962                                         writeStream.Close ();
 963                                         writeStream = null;
 964                                 } catch {}
 965                         }
 966
 967                         if (webResponse != null) {
 968                                 try {
 969                                         webResponse.Close ();
 970                                         webResponse = null;
 971                                 } catch {}
 972                         }
 973                 }
 974
 975                 void ISerializable.GetObjectData (SerializationInfo serializationInfo,
 976                                                   StreamingContext streamingContext)
 977                 {
 978                         GetObjectData (serializationInfo, streamingContext);
 979                 }
 980
 981                 protected override void GetObjectData (SerializationInfo serializationInfo,
 982                         StreamingContext streamingContext)
 983                 {
 984                         SerializationInfo info = serializationInfo;
 985
 986                         info.AddValue ("requestUri", requestUri, typeof (Uri));
 987                         info.AddValue ("actualUri", actualUri, typeof (Uri));
 988                         info.AddValue ("allowAutoRedirect", allowAutoRedirect);
 989                         info.AddValue ("allowBuffering", allowBuffering);
 990                         info.AddValue ("certificates", certificates, typeof (X509CertificateCollection));
 991                         info.AddValue ("connectionGroup", connectionGroup);
 992                         info.AddValue ("contentLength", contentLength);
 993                         info.AddValue ("webHeaders", webHeaders, typeof (WebHeaderCollection));
 994                         info.AddValue ("keepAlive", keepAlive);
 995                         info.AddValue ("maxAutoRedirect", maxAutoRedirect);
 996                         info.AddValue ("mediaType", mediaType);
 997                         info.AddValue ("method", method);
 998                         info.AddValue ("initialMethod", initialMethod);
 999                         info.AddValue ("pipelined", pipelined);
1000                         info.AddValue ("version", version, typeof (Version));
1001                         info.AddValue ("proxy", proxy, typeof (IWebProxy));
1002                         info.AddValue ("sendChunked", sendChunked);
1003                         info.AddValue ("timeout", timeout);
1004                         info.AddValue ("redirects", redirects);
1005                         info.AddValue ("host", host);
1006                 }
1007
1008                 void CheckRequestStarted ()
1009                 {
1010                         if (requestSent)
1011                                 throw new InvalidOperationException ("request started");
1012                 }
1013
1014                 internal void DoContinueDelegate (int statusCode, WebHeaderCollection headers)
1015                 {
1016                         if (continueDelegate != null)
1017                                 continueDelegate (statusCode, headers);
1018                 }
1019
1020                 bool Redirect (WebAsyncResult result, HttpStatusCode code)
1021                 {
1022                         redirects++;
1023                         Exception e = null;
1024                         string uriString = null;
1025
1026                         switch (code) {
1027                         case HttpStatusCode.Ambiguous: // 300
1028                                 e = new WebException ("Ambiguous redirect.");
1029                                 break;
1030                         case HttpStatusCode.MovedPermanently: // 301
1031                         case HttpStatusCode.Redirect: // 302
1032                         case HttpStatusCode.TemporaryRedirect: // 307
1033                                 /* MS follows the redirect for POST too
1034                                 if (method != "GET" && method != "HEAD") // 10.3
1035                                         return false;
1036                                 */
1037
1038                                 contentLength = -1;
1039                                 bodyBufferLength = 0;
1040                                 bodyBuffer = null;
1041                                 if (code != HttpStatusCode.TemporaryRedirect)
1042                                         method = "GET";
1043                                 uriString = webResponse.Headers ["Location"];
1044                                 break;
1045                         case HttpStatusCode.SeeOther: //303
1046                                 method = "GET";
1047                                 uriString = webResponse.Headers ["Location"];
1048                                 break;
1049                         case HttpStatusCode.NotModified: // 304
1050                                 return false;
1051                         case HttpStatusCode.UseProxy: // 305
1052                                 e = new NotImplementedException ("Proxy support not available.");
1053                                 break;
1054                         case HttpStatusCode.Unused: // 306
1055                         default:
1056                                 e = new ProtocolViolationException ("Invalid status code: " + (int) code);
1057                                 break;
1058                         }
1059
1060                         if (e != null)
1061                                 throw e;
1062
1063                         if (uriString == null)
1064                                 throw new WebException ("No Location header found for " + (int) code,
1065                                                         WebExceptionStatus.ProtocolError);
1066
1067                         Uri prev = actualUri;
1068                         try {
1069                                 actualUri = new Uri (actualUri, uriString);
1070                         } catch (Exception) {
1071                                 throw new WebException (String.Format ("Invalid URL ({0}) for {1}",
1072                                                                         uriString, (int) code),
1073                                                                         WebExceptionStatus.ProtocolError);
1074                         }
1075
1076                         hostChanged = (actualUri.Scheme != prev.Scheme || Host != prev.Authority);
1077                         return true;
1078                 }
1079
1080                 string GetHeaders ()
1081                 {
1082                         bool continue100 = false;
1083                         if (sendChunked) {
1084                                 continue100 = true;
1085                                 webHeaders.RemoveAndAdd ("Transfer-Encoding", "chunked");
1086                                 webHeaders.RemoveInternal ("Content-Length");
1087                         } else if (contentLength != -1) {
1088                                 if (ntlm_auth_state != NtlmAuthState.Challenge) {
1089                                         if (contentLength > 0)
1090                                                 continue100 = true;
1091
1092                                         webHeaders.SetInternal ("Content-Length", contentLength.ToString ());
1093                                 } else {
1094                                         webHeaders.SetInternal ("Content-Length", "0");
1095                                 }
1096                                 webHeaders.RemoveInternal ("Transfer-Encoding");
1097                         } else {
1098                                 webHeaders.RemoveInternal ("Content-Length");
1099                         }
1100
1101                         if (actualVersion == HttpVersion.Version11 && continue100 &&
1102                             servicePoint.SendContinue) { // RFC2616 8.2.3
1103                                 webHeaders.RemoveAndAdd ("Expect" , "100-continue");
1104                                 expectContinue = true;
1105                         } else {
1106                                 webHeaders.RemoveInternal ("Expect");
1107                                 expectContinue = false;
1108                         }
1109
1110                         bool proxy_query = ProxyQuery;
1111                         string connectionHeader = (proxy_query) ? "Proxy-Connection" : "Connection";
1112                         webHeaders.RemoveInternal ((!proxy_query) ? "Proxy-Connection" : "Connection");
1113                         Version proto_version = servicePoint.ProtocolVersion;
1114                         bool spoint10 = (proto_version == null || proto_version == HttpVersion.Version10);
1115
1116                         if (keepAlive && (version == HttpVersion.Version10 || spoint10)) {
1117                                 webHeaders.RemoveAndAdd (connectionHeader, "keep-alive");
1118                         } else if (!keepAlive && version == HttpVersion.Version11) {
1119                                 webHeaders.RemoveAndAdd (connectionHeader, "close");
1120                         }
1121
1122                         webHeaders.SetInternal ("Host", Host);
1123                         if (cookieContainer != null) {
1124                                 string cookieHeader = cookieContainer.GetCookieHeader (actualUri);
1125                                 if (cookieHeader != "")
1126                                         webHeaders.SetInternal ("Cookie", cookieHeader);
1127                         }
1128
1129                         string accept_encoding = null;
1130                         if ((auto_decomp & DecompressionMethods.GZip) != 0)
1131                                 accept_encoding = "gzip";
1132                         if ((auto_decomp & DecompressionMethods.Deflate) != 0)
1133                                 accept_encoding = accept_encoding != null ? "gzip, deflate" : "deflate";
1134                         if (accept_encoding != null)
1135                                 webHeaders.RemoveAndAdd ("Accept-Encoding", accept_encoding);
1136
1137                         if (!usedPreAuth && preAuthenticate)
1138                                 DoPreAuthenticate ();
1139
1140                         return webHeaders.ToString ();
1141                 }
1142
1143                 void DoPreAuthenticate ()
1144                 {
1145                         bool isProxy = (proxy != null && !proxy.IsBypassed (actualUri));
1146                         ICredentials creds = (!isProxy || credentials != null) ? credentials : proxy.Credentials;
1147                         Authorization auth = AuthenticationManager.PreAuthenticate (this, creds);
1148                         if (auth == null)
1149                                 return;
1150
1151                         webHeaders.RemoveInternal ("Proxy-Authorization");
1152                         webHeaders.RemoveInternal ("Authorization");
1153                         string authHeader = (isProxy && credentials == null) ? "Proxy-Authorization" : "Authorization";
1154                         webHeaders [authHeader] = auth.Message;
1155                         usedPreAuth = true;
1156                 }
1157
1158                 internal void SetWriteStreamError (WebExceptionStatus status, Exception exc)
1159                 {
1160                         if (Aborted)
1161                                 return;
1162
1163                         WebAsyncResult r = asyncWrite;
1164                         if (r == null)
1165                                 r = asyncRead;
1166
1167                         if (r != null) {
1168                                 string msg;
1169                                 WebException wex;
1170                                 if (exc == null) {
1171                                         msg = "Error: " + status;
1172                                         wex = new WebException (msg, status);
1173                                 } else {
1174                                         msg = String.Format ("Error: {0} ({1})", status, exc.Message);
1175                                         wex = new WebException (msg, exc, status);
1176                                 }
1177                                 r.SetCompleted (false, wex);
1178                                 r.DoCallback ();
1179                         }
1180                 }
1181
1182                 internal void SendRequestHeaders (bool propagate_error)
1183                 {
1184                         StringBuilder req = new StringBuilder ();
1185                         string query;
1186                         if (!ProxyQuery) {
1187                                 query = actualUri.PathAndQuery;
1188                         } else {
1189                                 query = String.Format ("{0}://{1}{2}",  actualUri.Scheme,
1190                                                                         Host,
1191                                                                         actualUri.PathAndQuery);
1192                         }
1193
1194                         if (!force_version && servicePoint.ProtocolVersion != null && servicePoint.ProtocolVersion < version) {
1195                                 actualVersion = servicePoint.ProtocolVersion;
1196                         } else {
1197                                 actualVersion = version;
1198                         }
1199
1200                         req.AppendFormat ("{0} {1} HTTP/{2}.{3}\r\n", method, query,
1201                                                                 actualVersion.Major, actualVersion.Minor);
1202                         req.Append (GetHeaders ());
1203                         string reqstr = req.ToString ();
1204                         byte [] bytes = Encoding.UTF8.GetBytes (reqstr);
1205                         try {
1206                                 writeStream.SetHeaders (bytes);
1207                         } catch (WebException wexc) {
1208                                 SetWriteStreamError (wexc.Status, wexc);
1209                                 if (propagate_error)
1210                                         throw;
1211                         } catch (Exception exc) {
1212                                 SetWriteStreamError (WebExceptionStatus.SendFailure, exc);
1213                                 if (propagate_error)
1214                                         throw;
1215                         }
1216                 }
1217
1218                 internal void SetWriteStream (WebConnectionStream stream)
1219                 {
1220                         if (Aborted)
1221                                 return;
1222
1223                         writeStream = stream;
1224                         if (bodyBuffer != null) {
1225                                 webHeaders.RemoveInternal ("Transfer-Encoding");
1226                                 contentLength = bodyBufferLength;
1227                                 writeStream.SendChunked = false;
1228                         }
1229
1230                         SendRequestHeaders (false);
1231
1232                         haveRequest = true;
1233
1234                         if (bodyBuffer != null) {
1235                                 // The body has been written and buffered. The request "user"
1236                                 // won't write it again, so we must do it.
1237                                 if (ntlm_auth_state != NtlmAuthState.Challenge) {
1238                                         writeStream.Write (bodyBuffer, 0, bodyBufferLength);
1239                                         bodyBuffer = null;
1240                                         writeStream.Close ();
1241                                 }
1242                         } else if (method != "HEAD" && method != "GET" && method != "MKCOL" && method != "CONNECT" &&
1243                                         method != "TRACE") {
1244                                 if (getResponseCalled && !writeStream.RequestWritten)
1245                                         writeStream.WriteRequest ();
1246                         }
1247
1248                         if (asyncWrite != null) {
1249                                 asyncWrite.SetCompleted (false, stream);
1250                                 asyncWrite.DoCallback ();
1251                                 asyncWrite = null;
1252                         }
1253                 }
1254
1255                 internal void SetResponseError (WebExceptionStatus status, Exception e, string where)
1256                 {
1257                         if (Aborted)
1258                                 return;
1259                         lock (locker) {
1260                         string msg = String.Format ("Error getting response stream ({0}): {1}", where, status);
1261                         WebAsyncResult r = asyncRead;
1262                         if (r == null)
1263                                 r = asyncWrite;
1264
1265                         WebException wexc;
1266                         if (e is WebException) {
1267                                 wexc = (WebException) e;
1268                         } else {
1269                                 wexc = new WebException (msg, e, status, null);
1270                         }
1271                         if (r != null) {
1272                                 if (!r.IsCompleted) {
1273                                         r.SetCompleted (false, wexc);
1274                                         r.DoCallback ();
1275                                 } else if (r == asyncWrite) {
1276                                         saved_exc = wexc;
1277                                 }
1278                                 haveResponse = true;
1279                                 asyncRead = null;
1280                                 asyncWrite = null;
1281                         } else {
1282                                 haveResponse = true;
1283                                 saved_exc = wexc;
1284                         }
1285                         }
1286                 }
1287
1288                 void CheckSendError (WebConnectionData data)
1289                 {
1290                         // Got here, but no one called GetResponse
1291                         int status = data.StatusCode;
1292                         if (status < 400 || status == 401 || status == 407)
1293                                 return;
1294
1295                         if (writeStream != null && asyncRead == null && !writeStream.CompleteRequestWritten) {
1296                                 // The request has not been completely sent and we got here!
1297                                 // We should probably just close and cause an error in any case,
1298                                 saved_exc = new WebException (data.StatusDescription, null, WebExceptionStatus.ProtocolError, webResponse);
1299                                 if (allowBuffering || sendChunked || writeStream.totalWritten >= contentLength) {
1300                                         webResponse.ReadAll ();
1301                                 } else {
1302                                         writeStream.IgnoreIOErrors = true;
1303                                 }
1304                         }
1305                 }
1306
1307                 void HandleNtlmAuth (WebAsyncResult r)
1308                 {
1309                         WebConnectionStream wce = webResponse.GetResponseStream () as WebConnectionStream;
1310                         if (wce != null) {
1311                                 WebConnection cnc = wce.Connection;
1312                                 cnc.PriorityRequest = this;
1313                                 bool isProxy = (proxy != null && !proxy.IsBypassed (actualUri));
1314                                 ICredentials creds = (!isProxy) ? credentials : proxy.Credentials;
1315                                 if (creds != null) {
1316                                         cnc.NtlmCredential = creds.GetCredential (requestUri, "NTLM");
1317                                         cnc.UnsafeAuthenticatedConnectionSharing = unsafe_auth_blah;
1318                                 }
1319                         }
1320                         r.Reset ();
1321                         finished_reading = false;
1322                         haveResponse = false;
1323                         webResponse.ReadAll ();
1324                         webResponse = null;
1325                 }
1326
1327                 internal void SetResponseData (WebConnectionData data)
1328                 {
1329                         lock (locker) {
1330                         if (Aborted) {
1331                                 if (data.stream != null)
1332                                         data.stream.Close ();
1333                                 return;
1334                         }
1335
1336                         WebException wexc = null;
1337                         try {
1338                                 webResponse = new HttpWebResponse (actualUri, method, data, cookieContainer);
1339                         } catch (Exception e) {
1340                                 wexc = new WebException (e.Message, e, WebExceptionStatus.ProtocolError, null);
1341                                 if (data.stream != null)
1342                                         data.stream.Close ();
1343                         }
1344
1345                         if (wexc == null && (method == "POST" || method == "PUT")) {
1346                                 CheckSendError (data);
1347                                 if (saved_exc != null)
1348                                         wexc = (WebException) saved_exc;
1349                         }
1350
1351                         WebAsyncResult r = asyncRead;
1352
1353                         bool forced = false;
1354                         if (r == null && webResponse != null) {
1355                                 // This is a forced completion (302, 204)...
1356                                 forced = true;
1357                                 r = new WebAsyncResult (null, null);
1358                                 r.SetCompleted (false, webResponse);
1359                         }
1360
1361                         if (r != null) {
1362                                 if (wexc != null) {
1363                                         haveResponse = true;
1364                                         if (!r.IsCompleted)
1365                                                 r.SetCompleted (false, wexc);
1366                                         r.DoCallback ();
1367                                         return;
1368                                 }
1369
1370                                 bool redirected;
1371                                 try {
1372                                         redirected = CheckFinalStatus (r);
1373                                         if (!redirected) {
1374                                                 if (ntlm_auth_state != NtlmAuthState.None && authCompleted && webResponse != null
1375                                                         && (int)webResponse.StatusCode < 400) {
1376                                                         WebConnectionStream wce = webResponse.GetResponseStream () as WebConnectionStream;
1377                                                         if (wce != null) {
1378                                                                 WebConnection cnc = wce.Connection;
1379                                                                 cnc.NtlmAuthenticated = true;
1380                                                         }
1381                                                 }
1382
1383                                                 // clear internal buffer so that it does not
1384                                                 // hold possible big buffer (bug #397627)
1385                                                 if (writeStream != null)
1386                                                         writeStream.KillBuffer ();
1387
1388                                                 haveResponse = true;
1389                                                 r.SetCompleted (false, webResponse);
1390                                                 r.DoCallback ();
1391                                         } else {
1392                                                 if (webResponse != null) {
1393                                                         if (ntlm_auth_state != NtlmAuthState.None) {
1394                                                                 HandleNtlmAuth (r);
1395                                                                 return;
1396                                                         }
1397                                                         webResponse.Close ();
1398                                                 }
1399                                                 finished_reading = false;
1400                                                 haveResponse = false;
1401                                                 webResponse = null;
1402                                                 r.Reset ();
1403                                                 servicePoint = GetServicePoint ();
1404                                                 abortHandler = servicePoint.SendRequest (this, connectionGroup);
1405                                         }
1406                                 } catch (WebException wexc2) {
1407                                         if (forced) {
1408                                                 saved_exc = wexc2;
1409                                                 haveResponse = true;
1410                                         }
1411                                         r.SetCompleted (false, wexc2);
1412                                         r.DoCallback ();
1413                                         return;
1414                                 } catch (Exception ex) {
1415                                         wexc = new WebException (ex.Message, ex, WebExceptionStatus.ProtocolError, null);
1416                                         if (forced) {
1417                                                 saved_exc = wexc;
1418                                                 haveResponse = true;
1419                                         }
1420                                         r.SetCompleted (false, wexc);
1421                                         r.DoCallback ();
1422                                         return;
1423                                 }
1424                         }
1425                         }
1426                 }
1427
1428                 bool CheckAuthorization (WebResponse response, HttpStatusCode code)
1429                 {
1430                         authCompleted = false;
1431                         if (code == HttpStatusCode.Unauthorized && credentials == null)
1432                                 return false;
1433
1434                         bool isProxy = (code == HttpStatusCode.ProxyAuthenticationRequired);
1435                         if (isProxy && (proxy == null || proxy.Credentials == null))
1436                                 return false;
1437
1438                         string [] authHeaders = response.Headers.GetValues ( (isProxy) ? "Proxy-Authenticate" : "WWW-Authenticate");
1439                         if (authHeaders == null || authHeaders.Length == 0)
1440                                 return false;
1441
1442                         ICredentials creds = (!isProxy) ? credentials : proxy.Credentials;
1443                         Authorization auth = null;
1444                         foreach (string authHeader in authHeaders) {
1445                                 auth = AuthenticationManager.Authenticate (authHeader, this, creds);
1446                                 if (auth != null)
1447                                         break;
1448                         }
1449                         if (auth == null)
1450                                 return false;
1451                         webHeaders [(isProxy) ? "Proxy-Authorization" : "Authorization"] = auth.Message;
1452                         authCompleted = auth.Complete;
1453                         bool is_ntlm = (auth.Module.AuthenticationType == "NTLM");
1454                         if (is_ntlm)
1455                                 ntlm_auth_state = (NtlmAuthState)((int) ntlm_auth_state + 1);
1456                         return true;
1457                 }
1458
1459                 // Returns true if redirected
1460                 bool CheckFinalStatus (WebAsyncResult result)
1461                 {
1462                         if (result.GotException) {
1463                                 bodyBuffer = null;
1464                                 throw result.Exception;
1465                         }
1466
1467                         Exception throwMe = result.Exception;
1468
1469                         HttpWebResponse resp = result.Response;
1470                         WebExceptionStatus protoError = WebExceptionStatus.ProtocolError;
1471                         HttpStatusCode code = 0;
1472                         if (throwMe == null && webResponse != null) {
1473                                 code = webResponse.StatusCode;
1474                                 if (!authCompleted && ((code == HttpStatusCode.Unauthorized && credentials != null) ||
1475                                      (ProxyQuery && code == HttpStatusCode.ProxyAuthenticationRequired))) {
1476                                         if (!usedPreAuth && CheckAuthorization (webResponse, code)) {
1477                                                 // Keep the written body, so it can be rewritten in the retry
1478                                                 if (InternalAllowBuffering) {
1479                                                         // NTLM: This is to avoid sending data in the 'challenge' request
1480                                                         // We save it in the first request (first 401), don't send anything
1481                                                         // in the challenge request and send it in the response request along
1482                                                         // with the buffers kept form the first request.
1483                                                         if (ntlm_auth_state != NtlmAuthState.Response) {
1484                                                                 bodyBuffer = writeStream.WriteBuffer;
1485                                                                 bodyBufferLength = writeStream.WriteBufferLength;
1486                                                         }
1487                                                         return true;
1488                                                 } else if (method != "PUT" && method != "POST") {
1489                                                         bodyBuffer = null;
1490                                                         return true;
1491                                                 }
1492
1493                                                 writeStream.InternalClose ();
1494                                                 writeStream = null;
1495                                                 webResponse.Close ();
1496                                                 webResponse = null;
1497                                                 bodyBuffer = null;
1498
1499                                                 throw new WebException ("This request requires buffering " +
1500                                                                         "of data for authentication or " +
1501                                                                         "redirection to be sucessful.");
1502                                         }
1503                                 }
1504
1505                                 bodyBuffer = null;
1506                                 if ((int) code >= 400) {
1507                                         string err = String.Format ("The remote server returned an error: ({0}) {1}.",
1508                                                                     (int) code, webResponse.StatusDescription);
1509                                         throwMe = new WebException (err, null, protoError, webResponse);
1510                                         webResponse.ReadAll ();
1511                                 } else if ((int) code == 304 && allowAutoRedirect) {
1512                                         string err = String.Format ("The remote server returned an error: ({0}) {1}.",
1513                                                                     (int) code, webResponse.StatusDescription);
1514                                         throwMe = new WebException (err, null, protoError, webResponse);
1515                                 } else if ((int) code >= 300 && allowAutoRedirect && redirects >= maxAutoRedirect) {
1516                                         throwMe = new WebException ("Max. redirections exceeded.", null,
1517                                                                     protoError, webResponse);
1518                                         webResponse.ReadAll ();
1519                                 }
1520                         }
1521
1522                         bodyBuffer = null;
1523                         if (throwMe == null) {
1524                                 bool b = false;
1525                                 int c = (int) code;
1526                                 if (allowAutoRedirect && c >= 300) {
1527                                         if (InternalAllowBuffering && writeStream.WriteBufferLength > 0) {
1528                                                 bodyBuffer = writeStream.WriteBuffer;
1529                                                 bodyBufferLength = writeStream.WriteBufferLength;
1530                                         }
1531                                         b = Redirect (result, code);
1532                                 }
1533
1534                                 if (resp != null && c >= 300 && c != 304)
1535                                         resp.ReadAll ();
1536
1537                                 return b;
1538                         }
1539
1540                         if (writeStream != null) {
1541                                 writeStream.InternalClose ();
1542                                 writeStream = null;
1543                         }
1544
1545                         webResponse = null;
1546
1547                         throw throwMe;
1548                 }
1549         }
1550 }
1551