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         [Serializable]
  50         public class HttpWebRequest : WebRequest, ISerializable {
  51                 Uri requestUri;
  52                 Uri actualUri;
  53                 bool hostChanged;
  54                 bool allowAutoRedirect = true;
  55                 bool allowBuffering = true;
  56                 X509CertificateCollection certificates;
  57                 string connectionGroup;
  58                 long contentLength = -1;
  59                 HttpContinueDelegate continueDelegate;
  60                 CookieContainer cookieContainer;
  61                 ICredentials credentials;
  62                 bool haveResponse;
  63                 bool haveRequest;
  64                 bool requestSent;
  65                 WebHeaderCollection webHeaders;
  66                 bool keepAlive = true;
  67                 int maxAutoRedirect = 50;
  68                 string mediaType = String.Empty;
  69                 string method = "GET";
  70                 string initialMethod = "GET";
  71                 bool pipelined = true;
  72                 bool preAuthenticate;
  73                 bool usedPreAuth;
  74                 Version version = HttpVersion.Version11;
  75                 bool force_version;
  76                 Version actualVersion;
  77                 IWebProxy proxy;
  78                 bool sendChunked;
  79                 ServicePoint servicePoint;
  80                 int timeout = 100000;
  81
  82                 WebConnectionStream writeStream;
  83                 HttpWebResponse webResponse;
  84                 WebAsyncResult asyncWrite;
  85                 WebAsyncResult asyncRead;
  86                 EventHandler abortHandler;
  87                 int aborted;
  88                 bool gotRequestStream;
  89                 int redirects;
  90                 bool expectContinue;
  91                 bool authCompleted;
  92                 byte[] bodyBuffer;
  93                 int bodyBufferLength;
  94                 bool getResponseCalled;
  95                 Exception saved_exc;
  96                 object locker = new object ();
  97                 bool finished_reading;
  98                 internal WebConnection WebConnection;
  99                 DecompressionMethods auto_decomp;
 100                 int maxResponseHeadersLength;
 101                 static int defaultMaxResponseHeadersLength;
 102                 int readWriteTimeout = 300000; // ms
 103
 104                 enum NtlmAuthState {
 105                         None,
 106                         Challenge,
 107                         Response
 108                 }
 109                 NtlmAuthState ntlm_auth_state;
 110                 string host;
 111
 112                 // Constructors
 113                 static HttpWebRequest ()
 114                 {
 115                         defaultMaxResponseHeadersLength = 64 * 1024;
 116 #if !NET_2_1
 117                         NetConfig config = ConfigurationSettings.GetConfig ("system.net/settings") as NetConfig;
 118                         if (config != null) {
 119                                 int x = config.MaxResponseHeadersLength;
 120                                 if (x != -1)
 121                                         x *= 64;
 122
 123                                 defaultMaxResponseHeadersLength = x;
 124                         }
 125 #endif
 126                 }
 127
 128 #if NET_2_1
 129                 public
 130 #else
 131                 internal
 132 #endif
 133                 HttpWebRequest (Uri uri)
 134                 {
 135                         this.requestUri = uri;
 136                         this.actualUri = uri;
 137                         this.proxy = GlobalProxySelection.Select;
 138                         this.webHeaders = new WebHeaderCollection (WebHeaderCollection.HeaderInfo.Request);
 139                         ThrowOnError = true;
 140                 }
 141
 142                 [Obsolete ("Serialization is obsoleted for this type", false)]
 143                 protected HttpWebRequest (SerializationInfo serializationInfo, StreamingContext streamingContext)
 144                 {
 145                         SerializationInfo info = serializationInfo;
 146
 147                         requestUri = (Uri) info.GetValue ("requestUri", typeof (Uri));
 148                         actualUri = (Uri) info.GetValue ("actualUri", typeof (Uri));
 149                         allowAutoRedirect = info.GetBoolean ("allowAutoRedirect");
 150                         allowBuffering = info.GetBoolean ("allowBuffering");
 151                         certificates = (X509CertificateCollection) info.GetValue ("certificates", typeof (X509CertificateCollection));
 152                         connectionGroup = info.GetString ("connectionGroup");
 153                         contentLength = info.GetInt64 ("contentLength");
 154                         webHeaders = (WebHeaderCollection) info.GetValue ("webHeaders", typeof (WebHeaderCollection));
 155                         keepAlive = info.GetBoolean ("keepAlive");
 156                         maxAutoRedirect = info.GetInt32 ("maxAutoRedirect");
 157                         mediaType = info.GetString ("mediaType");
 158                         method = info.GetString ("method");
 159                         initialMethod = info.GetString ("initialMethod");
 160                         pipelined = info.GetBoolean ("pipelined");
 161                         version = (Version) info.GetValue ("version", typeof (Version));
 162                         proxy = (IWebProxy) info.GetValue ("proxy", typeof (IWebProxy));
 163                         sendChunked = info.GetBoolean ("sendChunked");
 164                         timeout = info.GetInt32 ("timeout");
 165                         redirects = info.GetInt32 ("redirects");
 166                         host = info.GetString ("host");
 167                 }
 168
 169                 // Properties
 170
 171                 public string Accept {
 172                         get { return webHeaders ["Accept"]; }
 173                         set {
 174                                 CheckRequestStarted ();
 175                                 webHeaders.RemoveAndAdd ("Accept", value);
 176                         }
 177                 }
 178
 179                 public Uri Address {
 180                         get { return actualUri; }
 181                         internal set { actualUri = value; } // Used by Ftp+proxy
 182                 }
 183
 184                 public bool AllowAutoRedirect {
 185                         get { return allowAutoRedirect; }
 186                         set { this.allowAutoRedirect = value; }
 187                 }
 188
 189                 public bool AllowWriteStreamBuffering {
 190                         get { return allowBuffering; }
 191                         set { allowBuffering = value; }
 192                 }
 193
 194                 static Exception GetMustImplement ()
 195                 {
 196                         return new NotImplementedException ();
 197                 }
 198
 199                 public DecompressionMethods AutomaticDecompression
 200                 {
 201                         get {
 202                                 return auto_decomp;
 203                         }
 204                         set {
 205                                 CheckRequestStarted ();
 206                                 auto_decomp = value;
 207                         }
 208                 }
 209
 210                 internal bool InternalAllowBuffering {
 211                         get {
 212                                 return (allowBuffering && (method != "HEAD" && method != "GET" &&
 213                                                         method != "MKCOL" && method != "CONNECT" &&
 214                                                         method != "TRACE"));
 215                         }
 216                 }
 217
 218                 public X509CertificateCollection ClientCertificates {
 219                         get {
 220                                 if (certificates == null)
 221                                         certificates = new X509CertificateCollection ();
 222
 223                                 return certificates;
 224                         }
 225                         [MonoTODO]
 226                         set {
 227                                 throw GetMustImplement ();
 228                         }
 229                 }
 230
 231                 public string Connection {
 232                         get { return webHeaders ["Connection"]; }
 233                         set {
 234                                 CheckRequestStarted ();
 235
 236                                 if (string.IsNullOrEmpty (value)) {
 237                                         webHeaders.RemoveInternal ("Connection");
 238                                         return;
 239                                 }
 240
 241                                 string val = value.ToLowerInvariant ();
 242                                 if (val.Contains ("keep-alive") || val.Contains ("close"))
 243                                         throw new ArgumentException ("Keep-Alive and Close may not be set with this property");
 244
 245                                 if (keepAlive)
 246                                         value = value + ", Keep-Alive";
 247
 248                                 webHeaders.RemoveAndAdd ("Connection", value);
 249                         }
 250                 }
 251
 252                 public override string ConnectionGroupName {
 253                         get { return connectionGroup; }
 254                         set { connectionGroup = value; }
 255                 }
 256
 257                 public override long ContentLength {
 258                         get { return contentLength; }
 259                         set {
 260                                 CheckRequestStarted ();
 261                                 if (value < 0)
 262                                         throw new ArgumentOutOfRangeException ("value", "Content-Length must be >= 0");
 263
 264                                 contentLength = value;
 265                         }
 266                 }
 267
 268                 internal long InternalContentLength {
 269                         set { contentLength = value; }
 270                 }
 271
 272                 internal bool ThrowOnError { get; set; }
 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.Equals (DateTime.MinValue))
 309                                         webHeaders.RemoveInternal ("Date");
 310                                 else
 311                                         webHeaders.RemoveAndAdd ("Date", value.ToUniversalTime ().ToString ("r", CultureInfo.InvariantCulture));
 312                         }
 313                 }
 314 #endif
 315                 [MonoTODO]
 316                 public static new RequestCachePolicy DefaultCachePolicy
 317                 {
 318                         get {
 319                                 throw GetMustImplement ();
 320                         }
 321                         set {
 322                                 throw GetMustImplement ();
 323                         }
 324                 }
 325
 326                 [MonoTODO]
 327                 public static int DefaultMaximumErrorResponseLength
 328                 {
 329                         get {
 330                                 throw GetMustImplement ();
 331                         }
 332                         set {
 333                                 throw GetMustImplement ();
 334                         }
 335                 }
 336
 337                 public string Expect {
 338                         get { return webHeaders ["Expect"]; }
 339                         set {
 340                                 CheckRequestStarted ();
 341                                 string val = value;
 342                                 if (val != null)
 343                                         val = val.Trim ().ToLower ();
 344
 345                                 if (val == null || val.Length == 0) {
 346                                         webHeaders.RemoveInternal ("Expect");
 347                                         return;
 348                                 }
 349
 350                                 if (val == "100-continue")
 351                                         throw new ArgumentException ("100-Continue cannot be set with this property.",
 352                                                                      "value");
 353                                 webHeaders.RemoveAndAdd ("Expect", value);
 354                         }
 355                 }
 356
 357                 public bool HaveResponse {
 358                         get { return haveResponse; }
 359                 }
 360
 361                 public override WebHeaderCollection Headers {
 362                         get { return webHeaders; }
 363                         set {
 364                                 CheckRequestStarted ();
 365                                 WebHeaderCollection newHeaders = new WebHeaderCollection (WebHeaderCollection.HeaderInfo.Request);
 366                                 int count = value.Count;
 367                                 for (int i = 0; i < count; i++)
 368                                         newHeaders.Add (value.GetKey (i), value.Get (i));
 369
 370                                 webHeaders = newHeaders;
 371                         }
 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.Length == 0)
 399                                 return false;
 400
 401                         if (val [0] == '.')
 402                                 return false;
 403
 404                         int idx = val.IndexOf ('/');
 405                         if (idx >= 0)
 406                                 return false;
 407
 408                         string u = scheme + "://" + val + "/";
 409                         return Uri.IsWellFormedUriString (u, UriKind.Absolute);
 410                 }
 411
 412                 public DateTime IfModifiedSince {
 413                         get {
 414                                 string str = webHeaders ["If-Modified-Since"];
 415                                 if (str == null)
 416                                         return DateTime.Now;
 417                                 try {
 418                                         return MonoHttpDate.Parse (str);
 419                                 } catch (Exception) {
 420                                         return DateTime.Now;
 421                                 }
 422                         }
 423                         set {
 424                                 CheckRequestStarted ();
 425                                 // rfc-1123 pattern
 426                                 webHeaders.SetInternal ("If-Modified-Since",
 427                                         value.ToUniversalTime ().ToString ("r", null));
 428                                 // TODO: check last param when using different locale
 429                         }
 430                 }
 431
 432                 public bool KeepAlive {
 433                         get {
 434                                 return keepAlive;
 435                         }
 436                         set {
 437                                 keepAlive = value;
 438                         }
 439                 }
 440
 441                 public int MaximumAutomaticRedirections {
 442                         get { return maxAutoRedirect; }
 443                         set {
 444                                 if (value <= 0)
 445                                         throw new ArgumentException ("Must be > 0", "value");
 446
 447                                 maxAutoRedirect = value;
 448                         }
 449                 }
 450
 451                 [MonoTODO ("Use this")]
 452                 public int MaximumResponseHeadersLength {
 453                         get { return maxResponseHeadersLength; }
 454                         set { maxResponseHeadersLength = value; }
 455                 }
 456
 457                 [MonoTODO ("Use this")]
 458                 public static int DefaultMaximumResponseHeadersLength {
 459                         get { return defaultMaxResponseHeadersLength; }
 460                         set { defaultMaxResponseHeadersLength = value; }
 461                 }
 462
 463                 public  int ReadWriteTimeout {
 464                         get { return readWriteTimeout; }
 465                         set {
 466                                 if (requestSent)
 467                                         throw new InvalidOperationException ("The request has already been sent.");
 468
 469                                 if (value < -1)
 470                                         throw new ArgumentOutOfRangeException ("value", "Must be >= -1");
 471
 472                                 readWriteTimeout = value;
 473                         }
 474                 }
 475
 476                 public string MediaType {
 477                         get { return mediaType; }
 478                         set {
 479                                 mediaType = value;
 480                         }
 481                 }
 482
 483                 public override string Method {
 484                         get { return this.method; }
 485                         set {
 486                                 if (value == null || value.Trim () == "")
 487                                         throw new ArgumentException ("not a valid method");
 488
 489                                 method = value.ToUpperInvariant ();
 490                                 if (method != "HEAD" && method != "GET" && method != "POST" && method != "PUT" &&
 491                                         method != "DELETE" && method != "CONNECT" && method != "TRACE" &&
 492                                         method != "MKCOL") {
 493                                         method = value;
 494                                 }
 495                         }
 496                 }
 497
 498                 public bool Pipelined {
 499                         get { return pipelined; }
 500                         set { pipelined = value; }
 501                 }
 502
 503                 public override bool PreAuthenticate {
 504                         get { return preAuthenticate; }
 505                         set { preAuthenticate = value; }
 506                 }
 507
 508                 public Version ProtocolVersion {
 509                         get { return version; }
 510                         set {
 511                                 if (value != HttpVersion.Version10 && value != HttpVersion.Version11)
 512                                         throw new ArgumentException ("value");
 513
 514                                 force_version = true;
 515                                 version = value;
 516                         }
 517                 }
 518
 519                 public override IWebProxy Proxy {
 520                         get { return proxy; }
 521                         set {
 522                                 CheckRequestStarted ();
 523                                 proxy = value;
 524                                 servicePoint = null; // we may need a new one
 525                         }
 526                 }
 527
 528                 public string Referer {
 529                         get { return webHeaders ["Referer"]; }
 530                         set {
 531                                 CheckRequestStarted ();
 532                                 if (value == null || value.Trim().Length == 0) {
 533                                         webHeaders.RemoveInternal ("Referer");
 534                                         return;
 535                                 }
 536                                 webHeaders.SetInternal ("Referer", value);
 537                         }
 538                 }
 539
 540                 public override Uri RequestUri {
 541                         get { return requestUri; }
 542                 }
 543
 544                 public bool SendChunked {
 545                         get { return sendChunked; }
 546                         set {
 547                                 CheckRequestStarted ();
 548                                 sendChunked = value;
 549                         }
 550                 }
 551
 552                 public ServicePoint ServicePoint {
 553                         get { return GetServicePoint (); }
 554                 }
 555
 556                 internal ServicePoint ServicePointNoLock {
 557                         get { return servicePoint; }
 558                 }
 559 #if NET_4_5
 560                 [MonoTODO ("for portable library support")]
 561                 public bool SupportsCookieContainer {
 562                         get {
 563                                 throw new NotImplementedException ();
 564                         }
 565                 }
 566 #endif
 567                 public override int Timeout {
 568                         get { return timeout; }
 569                         set {
 570                                 if (value < -1)
 571                                         throw new ArgumentOutOfRangeException ("value");
 572
 573                                 timeout = value;
 574                         }
 575                 }
 576
 577                 public string TransferEncoding {
 578                         get { return webHeaders ["Transfer-Encoding"]; }
 579                         set {
 580                                 CheckRequestStarted ();
 581                                 string val = value;
 582                                 if (val != null)
 583                                         val = val.Trim ().ToLower ();
 584
 585                                 if (val == null || val.Length == 0) {
 586                                         webHeaders.RemoveInternal ("Transfer-Encoding");
 587                                         return;
 588                                 }
 589
 590                                 if (val == "chunked")
 591                                         throw new ArgumentException ("Chunked encoding must be set with the SendChunked property");
 592
 593                                 if (!sendChunked)
 594                                         throw new ArgumentException ("SendChunked must be True", "value");
 595
 596                                 webHeaders.RemoveAndAdd ("Transfer-Encoding", value);
 597                         }
 598                 }
 599
 600                 public override bool UseDefaultCredentials
 601                 {
 602                         get { return CredentialCache.DefaultCredentials == Credentials; }
 603                         set { Credentials = value ? CredentialCache.DefaultCredentials : null; }
 604                 }
 605
 606                 public string UserAgent {
 607                         get { return webHeaders ["User-Agent"]; }
 608                         set { webHeaders.SetInternal ("User-Agent", value); }
 609                 }
 610
 611                 bool unsafe_auth_blah;
 612                 public bool UnsafeAuthenticatedConnectionSharing
 613                 {
 614                         get { return unsafe_auth_blah; }
 615                         set { unsafe_auth_blah = value; }
 616                 }
 617
 618                 internal bool GotRequestStream {
 619                         get { return gotRequestStream; }
 620                 }
 621
 622                 internal bool ExpectContinue {
 623                         get { return expectContinue; }
 624                         set { expectContinue = value; }
 625                 }
 626
 627                 internal Uri AuthUri {
 628                         get { return actualUri; }
 629                 }
 630
 631                 internal bool ProxyQuery {
 632                         get { return servicePoint.UsesProxy && !servicePoint.UseConnect; }
 633                 }
 634
 635                 // Methods
 636
 637                 internal ServicePoint GetServicePoint ()
 638                 {
 639                         lock (locker) {
 640                                 if (hostChanged || servicePoint == null) {
 641                                         servicePoint = ServicePointManager.FindServicePoint (actualUri, proxy);
 642                                         hostChanged = false;
 643                                 }
 644                         }
 645
 646                         return servicePoint;
 647                 }
 648
 649                 public void AddRange (int range)
 650                 {
 651                         AddRange ("bytes", (long) range);
 652                 }
 653
 654                 public void AddRange (int from, int to)
 655                 {
 656                         AddRange ("bytes", (long) from, (long) to);
 657                 }
 658
 659                 public void AddRange (string rangeSpecifier, int range)
 660                 {
 661                         AddRange (rangeSpecifier, (long) range);
 662                 }
 663
 664                 public void AddRange (string rangeSpecifier, int from, int to)
 665                 {
 666                         AddRange (rangeSpecifier, (long) from, (long) to);
 667                 }
 668 #if NET_4_0
 669                 public
 670 #else
 671                 internal
 672 #endif
 673                 void AddRange (long range)
 674                 {
 675                         AddRange ("bytes", (long) range);
 676                 }
 677
 678 #if NET_4_0
 679                 public
 680 #else
 681                 internal
 682 #endif
 683                 void AddRange (long from, long to)
 684                 {
 685                         AddRange ("bytes", from, to);
 686                 }
 687
 688 #if NET_4_0
 689                 public
 690 #else
 691                 internal
 692 #endif
 693                 void AddRange (string rangeSpecifier, long range)
 694                 {
 695                         if (rangeSpecifier == null)
 696                                 throw new ArgumentNullException ("rangeSpecifier");
 697                         if (!WebHeaderCollection.IsHeaderValue (rangeSpecifier))
 698                                 throw new ArgumentException ("Invalid range specifier", "rangeSpecifier");
 699
 700                         string r = webHeaders ["Range"];
 701                         if (r == null)
 702                                 r = rangeSpecifier + "=";
 703                         else {
 704                                 string old_specifier = r.Substring (0, r.IndexOf ('='));
 705                                 if (String.Compare (old_specifier, rangeSpecifier, StringComparison.OrdinalIgnoreCase) != 0)
 706                                         throw new InvalidOperationException ("A different range specifier is already in use");
 707                                 r += ",";
 708                         }
 709
 710                         string n = range.ToString (CultureInfo.InvariantCulture);
 711                         if (range < 0)
 712                                 r = r + "0" + n;
 713                         else
 714                                 r = r + n + "-";
 715                         webHeaders.RemoveAndAdd ("Range", r);
 716                 }
 717
 718 #if NET_4_0
 719                 public
 720 #else
 721                 internal
 722 #endif
 723                 void AddRange (string rangeSpecifier, long from, long to)
 724                 {
 725                         if (rangeSpecifier == null)
 726                                 throw new ArgumentNullException ("rangeSpecifier");
 727                         if (!WebHeaderCollection.IsHeaderValue (rangeSpecifier))
 728                                 throw new ArgumentException ("Invalid range specifier", "rangeSpecifier");
 729                         if (from > to || from < 0)
 730                                 throw new ArgumentOutOfRangeException ("from");
 731                         if (to < 0)
 732                                 throw new ArgumentOutOfRangeException ("to");
 733
 734                         string r = webHeaders ["Range"];
 735                         if (r == null)
 736                                 r = rangeSpecifier + "=";
 737                         else
 738                                 r += ",";
 739
 740                         r = String.Format ("{0}{1}-{2}", r, from, to);
 741                         webHeaders.RemoveAndAdd ("Range", r);
 742                 }
 743
 744
 745                 public override IAsyncResult BeginGetRequestStream (AsyncCallback callback, object state)
 746                 {
 747                         if (Aborted)
 748                                 throw new WebException ("The request was canceled.", WebExceptionStatus.RequestCanceled);
 749
 750                         bool send = !(method == "GET" || method == "CONNECT" || method == "HEAD" ||
 751                                         method == "TRACE");
 752                         if (method == null || !send)
 753                                 throw new ProtocolViolationException ("Cannot send data when method is: " + method);
 754
 755                         if (contentLength == -1 && !sendChunked && !allowBuffering && KeepAlive)
 756                                 throw new ProtocolViolationException ("Content-Length not set");
 757
 758                         string transferEncoding = TransferEncoding;
 759                         if (!sendChunked && transferEncoding != null && transferEncoding.Trim () != "")
 760                                 throw new ProtocolViolationException ("SendChunked should be true.");
 761
 762                         lock (locker)
 763                         {
 764                                 if (getResponseCalled)
 765                                         throw new InvalidOperationException ("The operation cannot be performed once the request has been submitted.");
 766
 767                                 if (asyncWrite != null) {
 768                                         throw new InvalidOperationException ("Cannot re-call start of asynchronous " +
 769                                                                 "method while a previous call is still in progress.");
 770                                 }
 771
 772                                 asyncWrite = new WebAsyncResult (this, callback, state);
 773                                 initialMethod = method;
 774                                 if (haveRequest) {
 775                                         if (writeStream != null) {
 776                                                 asyncWrite.SetCompleted (true, writeStream);
 777                                                 asyncWrite.DoCallback ();
 778                                                 return asyncWrite;
 779                                         }
 780                                 }
 781
 782                                 gotRequestStream = true;
 783                                 WebAsyncResult result = asyncWrite;
 784                                 if (!requestSent) {
 785                                         requestSent = true;
 786                                         redirects = 0;
 787                                         servicePoint = GetServicePoint ();
 788                                         abortHandler = servicePoint.SendRequest (this, connectionGroup);
 789                                 }
 790                                 return result;
 791                         }
 792                 }
 793
 794                 public override Stream EndGetRequestStream (IAsyncResult asyncResult)
 795                 {
 796                         if (asyncResult == null)
 797                                 throw new ArgumentNullException ("asyncResult");
 798
 799                         WebAsyncResult result = asyncResult as WebAsyncResult;
 800                         if (result == null)
 801                                 throw new ArgumentException ("Invalid IAsyncResult");
 802
 803                         asyncWrite = result;
 804                         result.WaitUntilComplete ();
 805
 806                         Exception e = result.Exception;
 807                         if (e != null)
 808                                 throw e;
 809
 810                         return result.WriteStream;
 811                 }
 812
 813                 public override Stream GetRequestStream()
 814                 {
 815                         IAsyncResult asyncResult = asyncWrite;
 816                         if (asyncResult == null) {
 817                                 asyncResult = BeginGetRequestStream (null, null);
 818                                 asyncWrite = (WebAsyncResult) asyncResult;
 819                         }
 820
 821                         if (!asyncResult.IsCompleted && !asyncResult.AsyncWaitHandle.WaitOne (timeout, false)) {
 822                                 Abort ();
 823                                 throw new WebException ("The request timed out", WebExceptionStatus.Timeout);
 824                         }
 825
 826                         return EndGetRequestStream (asyncResult);
 827                 }
 828
 829                 void CheckIfForceWrite ()
 830                 {
 831                         if (writeStream == null || writeStream.RequestWritten || !InternalAllowBuffering)
 832                                 return;
 833 #if NET_4_0
 834                         if (contentLength < 0 && writeStream.CanWrite == true && writeStream.WriteBufferLength < 0)
 835                                 return;
 836
 837                         if (contentLength < 0 && writeStream.WriteBufferLength >= 0)
 838                                 InternalContentLength = writeStream.WriteBufferLength;
 839 #else
 840                         if (contentLength < 0 && writeStream.CanWrite == true)
 841                                 return;
 842 #endif
 843
 844                         // This will write the POST/PUT if the write stream already has the expected
 845                         // amount of bytes in it (ContentLength) (bug #77753) or if the write stream
 846                         // contains data and it has been closed already (xamarin bug #1512).
 847
 848                         if (writeStream.WriteBufferLength == contentLength || (contentLength == -1 && writeStream.CanWrite == false))
 849                                 writeStream.WriteRequest ();
 850                 }
 851
 852                 public override IAsyncResult BeginGetResponse (AsyncCallback callback, object state)
 853                 {
 854                         if (Aborted)
 855                                 throw new WebException ("The request was canceled.", WebExceptionStatus.RequestCanceled);
 856
 857                         if (method == null)
 858                                 throw new ProtocolViolationException ("Method is null.");
 859
 860                         string transferEncoding = TransferEncoding;
 861                         if (!sendChunked && transferEncoding != null && transferEncoding.Trim () != "")
 862                                 throw new ProtocolViolationException ("SendChunked should be true.");
 863
 864                         Monitor.Enter (locker);
 865                         getResponseCalled = true;
 866                         if (asyncRead != null && !haveResponse) {
 867                                 Monitor.Exit (locker);
 868                                 throw new InvalidOperationException ("Cannot re-call start of asynchronous " +
 869                                                         "method while a previous call is still in progress.");
 870                         }
 871
 872                         CheckIfForceWrite ();
 873                         asyncRead = new WebAsyncResult (this, callback, state);
 874                         WebAsyncResult aread = asyncRead;
 875                         initialMethod = method;
 876                         if (haveResponse) {
 877                                 Exception saved = saved_exc;
 878                                 if (webResponse != null) {
 879                                         Monitor.Exit (locker);
 880                                         if (saved == null) {
 881                                                 aread.SetCompleted (true, webResponse);
 882                                         } else {
 883                                                 aread.SetCompleted (true, saved);
 884                                         }
 885                                         aread.DoCallback ();
 886                                         return aread;
 887                                 } else if (saved != null) {
 888                                         Monitor.Exit (locker);
 889                                         aread.SetCompleted (true, saved);
 890                                         aread.DoCallback ();
 891                                         return aread;
 892                                 }
 893                         }
 894
 895                         if (!requestSent) {
 896                                 requestSent = true;
 897                                 redirects = 0;
 898                                 servicePoint = GetServicePoint ();
 899                                 abortHandler = servicePoint.SendRequest (this, connectionGroup);
 900                         }
 901
 902                         Monitor.Exit (locker);
 903                         return aread;
 904                 }
 905
 906                 public override WebResponse EndGetResponse (IAsyncResult asyncResult)
 907                 {
 908                         if (asyncResult == null)
 909                                 throw new ArgumentNullException ("asyncResult");
 910
 911                         WebAsyncResult result = asyncResult as WebAsyncResult;
 912                         if (result == null)
 913                                 throw new ArgumentException ("Invalid IAsyncResult", "asyncResult");
 914
 915                         if (!result.WaitUntilComplete (timeout, false)) {
 916                                 Abort ();
 917                                 throw new WebException("The request timed out", WebExceptionStatus.Timeout);
 918                         }
 919
 920                         if (result.GotException)
 921                                 throw result.Exception;
 922
 923                         return result.Response;
 924                 }
 925
 926                 public override WebResponse GetResponse()
 927                 {
 928                         WebAsyncResult result = (WebAsyncResult) BeginGetResponse (null, null);
 929                         return EndGetResponse (result);
 930                 }
 931
 932                 internal bool FinishedReading {
 933                         get { return finished_reading; }
 934                         set { finished_reading = value; }
 935                 }
 936
 937                 internal bool Aborted {
 938                         get { return Interlocked.CompareExchange (ref aborted, 0, 0) == 1; }
 939                 }
 940
 941                 public override void Abort ()
 942                 {
 943                         if (Interlocked.CompareExchange (ref aborted, 1, 0) == 1)
 944                                 return;
 945
 946                         if (haveResponse && finished_reading)
 947                                 return;
 948
 949                         haveResponse = true;
 950                         if (abortHandler != null) {
 951                                 try {
 952                                         abortHandler (this, EventArgs.Empty);
 953                                 } catch (Exception) {}
 954                                 abortHandler = null;
 955                         }
 956
 957                         if (asyncWrite != null) {
 958                                 WebAsyncResult r = asyncWrite;
 959                                 if (!r.IsCompleted) {
 960                                         try {
 961                                                 WebException wexc = new WebException ("Aborted.", WebExceptionStatus.RequestCanceled);
 962                                                 r.SetCompleted (false, wexc);
 963                                                 r.DoCallback ();
 964                                         } catch {}
 965                                 }
 966                                 asyncWrite = null;
 967                         }
 968
 969                         if (asyncRead != null) {
 970                                 WebAsyncResult r = asyncRead;
 971                                 if (!r.IsCompleted) {
 972                                         try {
 973                                                 WebException wexc = new WebException ("Aborted.", WebExceptionStatus.RequestCanceled);
 974                                                 r.SetCompleted (false, wexc);
 975                                                 r.DoCallback ();
 976                                         } catch {}
 977                                 }
 978                                 asyncRead = null;
 979                         }
 980
 981                         if (writeStream != null) {
 982                                 try {
 983                                         writeStream.Close ();
 984                                         writeStream = null;
 985                                 } catch {}
 986                         }
 987
 988                         if (webResponse != null) {
 989                                 try {
 990                                         webResponse.Close ();
 991                                         webResponse = null;
 992                                 } catch {}
 993                         }
 994                 }
 995
 996                 void ISerializable.GetObjectData (SerializationInfo serializationInfo,
 997                                                   StreamingContext streamingContext)
 998                 {
 999                         GetObjectData (serializationInfo, streamingContext);
1000                 }
1001
1002                 protected override void GetObjectData (SerializationInfo serializationInfo,
1003                         StreamingContext streamingContext)
1004                 {
1005                         SerializationInfo info = serializationInfo;
1006
1007                         info.AddValue ("requestUri", requestUri, typeof (Uri));
1008                         info.AddValue ("actualUri", actualUri, typeof (Uri));
1009                         info.AddValue ("allowAutoRedirect", allowAutoRedirect);
1010                         info.AddValue ("allowBuffering", allowBuffering);
1011                         info.AddValue ("certificates", certificates, typeof (X509CertificateCollection));
1012                         info.AddValue ("connectionGroup", connectionGroup);
1013                         info.AddValue ("contentLength", contentLength);
1014                         info.AddValue ("webHeaders", webHeaders, typeof (WebHeaderCollection));
1015                         info.AddValue ("keepAlive", keepAlive);
1016                         info.AddValue ("maxAutoRedirect", maxAutoRedirect);
1017                         info.AddValue ("mediaType", mediaType);
1018                         info.AddValue ("method", method);
1019                         info.AddValue ("initialMethod", initialMethod);
1020                         info.AddValue ("pipelined", pipelined);
1021                         info.AddValue ("version", version, typeof (Version));
1022                         info.AddValue ("proxy", proxy, typeof (IWebProxy));
1023                         info.AddValue ("sendChunked", sendChunked);
1024                         info.AddValue ("timeout", timeout);
1025                         info.AddValue ("redirects", redirects);
1026                         info.AddValue ("host", host);
1027                 }
1028
1029                 void CheckRequestStarted ()
1030                 {
1031                         if (requestSent)
1032                                 throw new InvalidOperationException ("request started");
1033                 }
1034
1035                 internal void DoContinueDelegate (int statusCode, WebHeaderCollection headers)
1036                 {
1037                         if (continueDelegate != null)
1038                                 continueDelegate (statusCode, headers);
1039                 }
1040
1041                 bool Redirect (WebAsyncResult result, HttpStatusCode code)
1042                 {
1043                         redirects++;
1044                         Exception e = null;
1045                         string uriString = null;
1046
1047                         switch (code) {
1048                         case HttpStatusCode.Ambiguous: // 300
1049                                 e = new WebException ("Ambiguous redirect.");
1050                                 break;
1051                         case HttpStatusCode.MovedPermanently: // 301
1052                         case HttpStatusCode.Redirect: // 302
1053                         case HttpStatusCode.TemporaryRedirect: // 307
1054                                 /* MS follows the redirect for POST too
1055                                 if (method != "GET" && method != "HEAD") // 10.3
1056                                         return false;
1057                                 */
1058
1059                                 contentLength = -1;
1060                                 bodyBufferLength = 0;
1061                                 bodyBuffer = null;
1062                                 if (code != HttpStatusCode.TemporaryRedirect)
1063                                         method = "GET";
1064                                 uriString = webResponse.Headers ["Location"];
1065                                 break;
1066                         case HttpStatusCode.SeeOther: //303
1067                                 method = "GET";
1068                                 uriString = webResponse.Headers ["Location"];
1069                                 break;
1070                         case HttpStatusCode.NotModified: // 304
1071                                 return false;
1072                         case HttpStatusCode.UseProxy: // 305
1073                                 e = new NotImplementedException ("Proxy support not available.");
1074                                 break;
1075                         case HttpStatusCode.Unused: // 306
1076                         default:
1077                                 e = new ProtocolViolationException ("Invalid status code: " + (int) code);
1078                                 break;
1079                         }
1080
1081                         if (e != null)
1082                                 throw e;
1083
1084                         if (uriString == null)
1085                                 throw new WebException ("No Location header found for " + (int) code,
1086                                                         WebExceptionStatus.ProtocolError);
1087
1088                         Uri prev = actualUri;
1089                         try {
1090                                 actualUri = new Uri (actualUri, uriString);
1091                         } catch (Exception) {
1092                                 throw new WebException (String.Format ("Invalid URL ({0}) for {1}",
1093                                                                         uriString, (int) code),
1094                                                                         WebExceptionStatus.ProtocolError);
1095                         }
1096
1097                         hostChanged = (actualUri.Scheme != prev.Scheme || Host != prev.Authority);
1098                         return true;
1099                 }
1100
1101                 string GetHeaders ()
1102                 {
1103                         bool continue100 = false;
1104                         if (sendChunked) {
1105                                 continue100 = true;
1106                                 webHeaders.RemoveAndAdd ("Transfer-Encoding", "chunked");
1107                                 webHeaders.RemoveInternal ("Content-Length");
1108                         } else if (contentLength != -1) {
1109                                 if (ntlm_auth_state != NtlmAuthState.Challenge) {
1110                                         if (contentLength > 0)
1111                                                 continue100 = true;
1112
1113                                         webHeaders.SetInternal ("Content-Length", contentLength.ToString ());
1114                                 } else {
1115                                         webHeaders.SetInternal ("Content-Length", "0");
1116                                 }
1117                                 webHeaders.RemoveInternal ("Transfer-Encoding");
1118                         } else {
1119                                 webHeaders.RemoveInternal ("Content-Length");
1120                         }
1121
1122                         if (actualVersion == HttpVersion.Version11 && continue100 &&
1123                             servicePoint.SendContinue) { // RFC2616 8.2.3
1124                                 webHeaders.RemoveAndAdd ("Expect" , "100-continue");
1125                                 expectContinue = true;
1126                         } else {
1127                                 webHeaders.RemoveInternal ("Expect");
1128                                 expectContinue = false;
1129                         }
1130
1131                         bool proxy_query = ProxyQuery;
1132                         string connectionHeader = (proxy_query) ? "Proxy-Connection" : "Connection";
1133                         webHeaders.RemoveInternal ((!proxy_query) ? "Proxy-Connection" : "Connection");
1134                         Version proto_version = servicePoint.ProtocolVersion;
1135                         bool spoint10 = (proto_version == null || proto_version == HttpVersion.Version10);
1136
1137                         if (keepAlive && (version == HttpVersion.Version10 || spoint10)) {
1138                                 webHeaders.RemoveAndAdd (connectionHeader, "keep-alive");
1139                         } else if (!keepAlive && version == HttpVersion.Version11) {
1140                                 webHeaders.RemoveAndAdd (connectionHeader, "close");
1141                         }
1142
1143                         webHeaders.SetInternal ("Host", Host);
1144                         if (cookieContainer != null) {
1145                                 string cookieHeader = cookieContainer.GetCookieHeader (actualUri);
1146                                 if (cookieHeader != "")
1147                                         webHeaders.RemoveAndAdd ("Cookie", cookieHeader);
1148                                 else
1149                                         webHeaders.RemoveInternal ("Cookie");
1150                         }
1151
1152                         string accept_encoding = null;
1153                         if ((auto_decomp & DecompressionMethods.GZip) != 0)
1154                                 accept_encoding = "gzip";
1155                         if ((auto_decomp & DecompressionMethods.Deflate) != 0)
1156                                 accept_encoding = accept_encoding != null ? "gzip, deflate" : "deflate";
1157                         if (accept_encoding != null)
1158                                 webHeaders.RemoveAndAdd ("Accept-Encoding", accept_encoding);
1159
1160                         if (!usedPreAuth && preAuthenticate)
1161                                 DoPreAuthenticate ();
1162
1163                         return webHeaders.ToString ();
1164                 }
1165
1166                 void DoPreAuthenticate ()
1167                 {
1168                         bool isProxy = (proxy != null && !proxy.IsBypassed (actualUri));
1169                         ICredentials creds = (!isProxy || credentials != null) ? credentials : proxy.Credentials;
1170                         Authorization auth = AuthenticationManager.PreAuthenticate (this, creds);
1171                         if (auth == null)
1172                                 return;
1173
1174                         webHeaders.RemoveInternal ("Proxy-Authorization");
1175                         webHeaders.RemoveInternal ("Authorization");
1176                         string authHeader = (isProxy && credentials == null) ? "Proxy-Authorization" : "Authorization";
1177                         webHeaders [authHeader] = auth.Message;
1178                         usedPreAuth = true;
1179                 }
1180
1181                 internal void SetWriteStreamError (WebExceptionStatus status, Exception exc)
1182                 {
1183                         if (Aborted)
1184                                 return;
1185
1186                         WebAsyncResult r = asyncWrite;
1187                         if (r == null)
1188                                 r = asyncRead;
1189
1190                         if (r != null) {
1191                                 string msg;
1192                                 WebException wex;
1193                                 if (exc == null) {
1194                                         msg = "Error: " + status;
1195                                         wex = new WebException (msg, status);
1196                                 } else {
1197                                         msg = String.Format ("Error: {0} ({1})", status, exc.Message);
1198                                         wex = new WebException (msg, exc, status);
1199                                 }
1200                                 r.SetCompleted (false, wex);
1201                                 r.DoCallback ();
1202                         }
1203                 }
1204
1205                 internal void SendRequestHeaders (bool propagate_error)
1206                 {
1207                         StringBuilder req = new StringBuilder ();
1208                         string query;
1209                         if (!ProxyQuery) {
1210                                 query = actualUri.PathAndQuery;
1211                         } else {
1212                                 query = String.Format ("{0}://{1}{2}",  actualUri.Scheme,
1213                                                                         Host,
1214                                                                         actualUri.PathAndQuery);
1215                         }
1216
1217                         if (!force_version && servicePoint.ProtocolVersion != null && servicePoint.ProtocolVersion < version) {
1218                                 actualVersion = servicePoint.ProtocolVersion;
1219                         } else {
1220                                 actualVersion = version;
1221                         }
1222
1223                         req.AppendFormat ("{0} {1} HTTP/{2}.{3}\r\n", method, query,
1224                                                                 actualVersion.Major, actualVersion.Minor);
1225                         req.Append (GetHeaders ());
1226                         string reqstr = req.ToString ();
1227                         byte [] bytes = Encoding.UTF8.GetBytes (reqstr);
1228                         try {
1229                                 writeStream.SetHeaders (bytes);
1230                         } catch (WebException wexc) {
1231                                 SetWriteStreamError (wexc.Status, wexc);
1232                                 if (propagate_error)
1233                                         throw;
1234                         } catch (Exception exc) {
1235                                 SetWriteStreamError (WebExceptionStatus.SendFailure, exc);
1236                                 if (propagate_error)
1237                                         throw;
1238                         }
1239                 }
1240
1241                 internal void SetWriteStream (WebConnectionStream stream)
1242                 {
1243                         if (Aborted)
1244                                 return;
1245
1246                         writeStream = stream;
1247                         if (bodyBuffer != null) {
1248                                 webHeaders.RemoveInternal ("Transfer-Encoding");
1249                                 contentLength = bodyBufferLength;
1250                                 writeStream.SendChunked = false;
1251                         }
1252
1253                         SendRequestHeaders (false);
1254
1255                         haveRequest = true;
1256
1257                         if (bodyBuffer != null) {
1258                                 // The body has been written and buffered. The request "user"
1259                                 // won't write it again, so we must do it.
1260                                 if (ntlm_auth_state != NtlmAuthState.Challenge) {
1261                                         writeStream.Write (bodyBuffer, 0, bodyBufferLength);
1262                                         bodyBuffer = null;
1263                                         writeStream.Close ();
1264                                 }
1265                         } else if (method != "HEAD" && method != "GET" && method != "MKCOL" && method != "CONNECT" &&
1266                                         method != "TRACE") {
1267                                 if (getResponseCalled && !writeStream.RequestWritten)
1268                                         writeStream.WriteRequest ();
1269                         }
1270
1271                         if (asyncWrite != null) {
1272                                 asyncWrite.SetCompleted (false, stream);
1273                                 asyncWrite.DoCallback ();
1274                                 asyncWrite = null;
1275                         }
1276                 }
1277
1278                 internal void SetResponseError (WebExceptionStatus status, Exception e, string where)
1279                 {
1280                         if (Aborted)
1281                                 return;
1282                         lock (locker) {
1283                         string msg = String.Format ("Error getting response stream ({0}): {1}", where, status);
1284                         WebAsyncResult r = asyncRead;
1285                         if (r == null)
1286                                 r = asyncWrite;
1287
1288                         WebException wexc;
1289                         if (e is WebException) {
1290                                 wexc = (WebException) e;
1291                         } else {
1292                                 wexc = new WebException (msg, e, status, null);
1293                         }
1294                         if (r != null) {
1295                                 if (!r.IsCompleted) {
1296                                         r.SetCompleted (false, wexc);
1297                                         r.DoCallback ();
1298                                 } else if (r == asyncWrite) {
1299                                         saved_exc = wexc;
1300                                 }
1301                                 haveResponse = true;
1302                                 asyncRead = null;
1303                                 asyncWrite = null;
1304                         } else {
1305                                 haveResponse = true;
1306                                 saved_exc = wexc;
1307                         }
1308                         }
1309                 }
1310
1311                 void CheckSendError (WebConnectionData data)
1312                 {
1313                         // Got here, but no one called GetResponse
1314                         int status = data.StatusCode;
1315                         if (status < 400 || status == 401 || status == 407)
1316                                 return;
1317
1318                         if (writeStream != null && asyncRead == null && !writeStream.CompleteRequestWritten) {
1319                                 // The request has not been completely sent and we got here!
1320                                 // We should probably just close and cause an error in any case,
1321                                 saved_exc = new WebException (data.StatusDescription, null, WebExceptionStatus.ProtocolError, webResponse);
1322                                 if (allowBuffering || sendChunked || writeStream.totalWritten >= contentLength) {
1323                                         webResponse.ReadAll ();
1324                                 } else {
1325                                         writeStream.IgnoreIOErrors = true;
1326                                 }
1327                         }
1328                 }
1329
1330                 void HandleNtlmAuth (WebAsyncResult r)
1331                 {
1332                         WebConnectionStream wce = webResponse.GetResponseStream () as WebConnectionStream;
1333                         if (wce != null) {
1334                                 WebConnection cnc = wce.Connection;
1335                                 cnc.PriorityRequest = this;
1336                                 bool isProxy = (proxy != null && !proxy.IsBypassed (actualUri));
1337                                 ICredentials creds = (!isProxy) ? credentials : proxy.Credentials;
1338                                 if (creds != null) {
1339                                         cnc.NtlmCredential = creds.GetCredential (requestUri, "NTLM");
1340                                         cnc.UnsafeAuthenticatedConnectionSharing = unsafe_auth_blah;
1341                                 }
1342                         }
1343                         r.Reset ();
1344                         finished_reading = false;
1345                         haveResponse = false;
1346                         webResponse.ReadAll ();
1347                         webResponse = null;
1348                 }
1349
1350                 internal void SetResponseData (WebConnectionData data)
1351                 {
1352                         lock (locker) {
1353                         if (Aborted) {
1354                                 if (data.stream != null)
1355                                         data.stream.Close ();
1356                                 return;
1357                         }
1358
1359                         WebException wexc = null;
1360                         try {
1361                                 webResponse = new HttpWebResponse (actualUri, method, data, cookieContainer);
1362                         } catch (Exception e) {
1363                                 wexc = new WebException (e.Message, e, WebExceptionStatus.ProtocolError, null);
1364                                 if (data.stream != null)
1365                                         data.stream.Close ();
1366                         }
1367
1368                         if (wexc == null && (method == "POST" || method == "PUT")) {
1369                                 CheckSendError (data);
1370                                 if (saved_exc != null)
1371                                         wexc = (WebException) saved_exc;
1372                         }
1373
1374                         WebAsyncResult r = asyncRead;
1375
1376                         bool forced = false;
1377                         if (r == null && webResponse != null) {
1378                                 // This is a forced completion (302, 204)...
1379                                 forced = true;
1380                                 r = new WebAsyncResult (null, null);
1381                                 r.SetCompleted (false, webResponse);
1382                         }
1383
1384                         if (r != null) {
1385                                 if (wexc != null) {
1386                                         haveResponse = true;
1387                                         if (!r.IsCompleted)
1388                                                 r.SetCompleted (false, wexc);
1389                                         r.DoCallback ();
1390                                         return;
1391                                 }
1392
1393                                 bool redirected;
1394                                 try {
1395                                         redirected = CheckFinalStatus (r);
1396                                         if (!redirected) {
1397                                                 if (ntlm_auth_state != NtlmAuthState.None && authCompleted && webResponse != null
1398                                                         && (int)webResponse.StatusCode < 400) {
1399                                                         WebConnectionStream wce = webResponse.GetResponseStream () as WebConnectionStream;
1400                                                         if (wce != null) {
1401                                                                 WebConnection cnc = wce.Connection;
1402                                                                 cnc.NtlmAuthenticated = true;
1403                                                         }
1404                                                 }
1405
1406                                                 // clear internal buffer so that it does not
1407                                                 // hold possible big buffer (bug #397627)
1408                                                 if (writeStream != null)
1409                                                         writeStream.KillBuffer ();
1410
1411                                                 haveResponse = true;
1412                                                 r.SetCompleted (false, webResponse);
1413                                                 r.DoCallback ();
1414                                         } else {
1415                                                 if (webResponse != null) {
1416                                                         if (ntlm_auth_state != NtlmAuthState.None) {
1417                                                                 HandleNtlmAuth (r);
1418                                                                 return;
1419                                                         }
1420                                                         webResponse.Close ();
1421                                                 }
1422                                                 finished_reading = false;
1423                                                 haveResponse = false;
1424                                                 webResponse = null;
1425                                                 r.Reset ();
1426                                                 servicePoint = GetServicePoint ();
1427                                                 abortHandler = servicePoint.SendRequest (this, connectionGroup);
1428                                         }
1429                                 } catch (WebException wexc2) {
1430                                         if (forced) {
1431                                                 saved_exc = wexc2;
1432                                                 haveResponse = true;
1433                                         }
1434                                         r.SetCompleted (false, wexc2);
1435                                         r.DoCallback ();
1436                                         return;
1437                                 } catch (Exception ex) {
1438                                         wexc = new WebException (ex.Message, ex, WebExceptionStatus.ProtocolError, null);
1439                                         if (forced) {
1440                                                 saved_exc = wexc;
1441                                                 haveResponse = true;
1442                                         }
1443                                         r.SetCompleted (false, wexc);
1444                                         r.DoCallback ();
1445                                         return;
1446                                 }
1447                         }
1448                         }
1449                 }
1450
1451                 bool CheckAuthorization (WebResponse response, HttpStatusCode code)
1452                 {
1453                         authCompleted = false;
1454                         if (code == HttpStatusCode.Unauthorized && credentials == null)
1455                                 return false;
1456
1457                         bool isProxy = (code == HttpStatusCode.ProxyAuthenticationRequired);
1458                         if (isProxy && (proxy == null || proxy.Credentials == null))
1459                                 return false;
1460
1461                         string [] authHeaders = response.Headers.GetValues_internal ( (isProxy) ? "Proxy-Authenticate" : "WWW-Authenticate", false);
1462                         if (authHeaders == null || authHeaders.Length == 0)
1463                                 return false;
1464
1465                         ICredentials creds = (!isProxy) ? credentials : proxy.Credentials;
1466                         Authorization auth = null;
1467                         foreach (string authHeader in authHeaders) {
1468                                 auth = AuthenticationManager.Authenticate (authHeader, this, creds);
1469                                 if (auth != null)
1470                                         break;
1471                         }
1472                         if (auth == null)
1473                                 return false;
1474                         webHeaders [(isProxy) ? "Proxy-Authorization" : "Authorization"] = auth.Message;
1475                         authCompleted = auth.Complete;
1476                         bool is_ntlm = (auth.Module.AuthenticationType == "NTLM");
1477                         if (is_ntlm)
1478                                 ntlm_auth_state = (NtlmAuthState)((int) ntlm_auth_state + 1);
1479                         return true;
1480                 }
1481
1482                 // Returns true if redirected
1483                 bool CheckFinalStatus (WebAsyncResult result)
1484                 {
1485                         if (result.GotException) {
1486                                 bodyBuffer = null;
1487                                 throw result.Exception;
1488                         }
1489
1490                         Exception throwMe = result.Exception;
1491
1492                         HttpWebResponse resp = result.Response;
1493                         WebExceptionStatus protoError = WebExceptionStatus.ProtocolError;
1494                         HttpStatusCode code = 0;
1495                         if (throwMe == null && webResponse != null) {
1496                                 code = webResponse.StatusCode;
1497                                 if (!authCompleted && ((code == HttpStatusCode.Unauthorized && credentials != null) ||
1498                                      (ProxyQuery && code == HttpStatusCode.ProxyAuthenticationRequired))) {
1499                                         if (!usedPreAuth && CheckAuthorization (webResponse, code)) {
1500                                                 // Keep the written body, so it can be rewritten in the retry
1501                                                 if (InternalAllowBuffering) {
1502                                                         // NTLM: This is to avoid sending data in the 'challenge' request
1503                                                         // We save it in the first request (first 401), don't send anything
1504                                                         // in the challenge request and send it in the response request along
1505                                                         // with the buffers kept form the first request.
1506                                                         if (ntlm_auth_state != NtlmAuthState.Response) {
1507                                                                 bodyBuffer = writeStream.WriteBuffer;
1508                                                                 bodyBufferLength = writeStream.WriteBufferLength;
1509                                                         }
1510                                                         return true;
1511                                                 } else if (method != "PUT" && method != "POST") {
1512                                                         bodyBuffer = null;
1513                                                         return true;
1514                                                 }
1515
1516                                                 if (!ThrowOnError)
1517                                                         return false;
1518
1519                                                 writeStream.InternalClose ();
1520                                                 writeStream = null;
1521                                                 webResponse.Close ();
1522                                                 webResponse = null;
1523                                                 bodyBuffer = null;
1524
1525                                                 throw new WebException ("This request requires buffering " +
1526                                                                         "of data for authentication or " +
1527                                                                         "redirection to be sucessful.");
1528                                         }
1529                                 }
1530
1531                                 bodyBuffer = null;
1532                                 if ((int) code >= 400) {
1533                                         string err = String.Format ("The remote server returned an error: ({0}) {1}.",
1534                                                                     (int) code, webResponse.StatusDescription);
1535                                         throwMe = new WebException (err, null, protoError, webResponse);
1536                                         webResponse.ReadAll ();
1537                                 } else if ((int) code == 304 && allowAutoRedirect) {
1538                                         string err = String.Format ("The remote server returned an error: ({0}) {1}.",
1539                                                                     (int) code, webResponse.StatusDescription);
1540                                         throwMe = new WebException (err, null, protoError, webResponse);
1541                                 } else if ((int) code >= 300 && allowAutoRedirect && redirects >= maxAutoRedirect) {
1542                                         throwMe = new WebException ("Max. redirections exceeded.", null,
1543                                                                     protoError, webResponse);
1544                                         webResponse.ReadAll ();
1545                                 }
1546                         }
1547
1548                         bodyBuffer = null;
1549                         if (throwMe == null) {
1550                                 bool b = false;
1551                                 int c = (int) code;
1552                                 if (allowAutoRedirect && c >= 300) {
1553                                         if (InternalAllowBuffering && writeStream.WriteBufferLength > 0) {
1554                                                 bodyBuffer = writeStream.WriteBuffer;
1555                                                 bodyBufferLength = writeStream.WriteBufferLength;
1556                                         }
1557                                         b = Redirect (result, code);
1558                                         if (b && ntlm_auth_state != 0)
1559                                                 ntlm_auth_state = 0;
1560                                 }
1561
1562                                 if (resp != null && c >= 300 && c != 304)
1563                                         resp.ReadAll ();
1564
1565                                 return b;
1566                         }
1567
1568                         if (!ThrowOnError)
1569                                 return false;
1570
1571                         if (writeStream != null) {
1572                                 writeStream.InternalClose ();
1573                                 writeStream = null;
1574                         }
1575
1576                         webResponse = null;
1577
1578                         throw throwMe;
1579                 }
1580         }
1581 }
1582