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;
  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                         this.webHeaders = new WebHeaderCollection (WebHeaderCollection.HeaderInfo.Request);
 143                         ThrowOnError = true;
 144                 }
 145
 146                 [Obsolete ("Serialization is obsoleted for this type", false)]
 147                 protected HttpWebRequest (SerializationInfo serializationInfo, StreamingContext streamingContext)
 148                 {
 149                         SerializationInfo info = serializationInfo;
 150
 151                         requestUri = (Uri) info.GetValue ("requestUri", typeof (Uri));
 152                         actualUri = (Uri) info.GetValue ("actualUri", typeof (Uri));
 153                         allowAutoRedirect = info.GetBoolean ("allowAutoRedirect");
 154                         allowBuffering = info.GetBoolean ("allowBuffering");
 155                         certificates = (X509CertificateCollection) info.GetValue ("certificates", typeof (X509CertificateCollection));
 156                         connectionGroup = info.GetString ("connectionGroup");
 157                         contentLength = info.GetInt64 ("contentLength");
 158                         webHeaders = (WebHeaderCollection) info.GetValue ("webHeaders", typeof (WebHeaderCollection));
 159                         keepAlive = info.GetBoolean ("keepAlive");
 160                         maxAutoRedirect = info.GetInt32 ("maxAutoRedirect");
 161                         mediaType = info.GetString ("mediaType");
 162                         method = info.GetString ("method");
 163                         initialMethod = info.GetString ("initialMethod");
 164                         pipelined = info.GetBoolean ("pipelined");
 165                         version = (Version) info.GetValue ("version", typeof (Version));
 166                         proxy = (IWebProxy) info.GetValue ("proxy", typeof (IWebProxy));
 167                         sendChunked = info.GetBoolean ("sendChunked");
 168                         timeout = info.GetInt32 ("timeout");
 169                         redirects = info.GetInt32 ("redirects");
 170                         host = info.GetString ("host");
 171                 }
 172
 173                 // Properties
 174
 175                 public string Accept {
 176                         get { return webHeaders ["Accept"]; }
 177                         set {
 178                                 CheckRequestStarted ();
 179                                 webHeaders.RemoveAndAdd ("Accept", value);
 180                         }
 181                 }
 182
 183                 public Uri Address {
 184                         get { return actualUri; }
 185                         internal set { actualUri = value; } // Used by Ftp+proxy
 186                 }
 187
 188                 public bool AllowAutoRedirect {
 189                         get { return allowAutoRedirect; }
 190                         set { this.allowAutoRedirect = value; }
 191                 }
 192
 193                 public bool AllowWriteStreamBuffering {
 194                         get { return allowBuffering; }
 195                         set { allowBuffering = value; }
 196                 }
 197
 198                 static Exception GetMustImplement ()
 199                 {
 200                         return new NotImplementedException ();
 201                 }
 202
 203                 public DecompressionMethods AutomaticDecompression
 204                 {
 205                         get {
 206                                 return auto_decomp;
 207                         }
 208                         set {
 209                                 CheckRequestStarted ();
 210                                 auto_decomp = value;
 211                         }
 212                 }
 213
 214                 internal bool InternalAllowBuffering {
 215                         get {
 216                                 return (allowBuffering && (method != "HEAD" && method != "GET" &&
 217                                                         method != "MKCOL" && method != "CONNECT" &&
 218                                                         method != "TRACE"));
 219                         }
 220                 }
 221
 222                 public X509CertificateCollection ClientCertificates {
 223                         get {
 224                                 if (certificates == null)
 225                                         certificates = new X509CertificateCollection ();
 226
 227                                 return certificates;
 228                         }
 229                         [MonoTODO]
 230                         set {
 231                                 throw GetMustImplement ();
 232                         }
 233                 }
 234
 235                 public string Connection {
 236                         get { return webHeaders ["Connection"]; }
 237                         set {
 238                                 CheckRequestStarted ();
 239
 240                                 if (string.IsNullOrEmpty (value)) {
 241                                         webHeaders.RemoveInternal ("Connection");
 242                                         return;
 243                                 }
 244
 245                                 string val = value.ToLowerInvariant ();
 246                                 if (val.Contains ("keep-alive") || val.Contains ("close"))
 247                                         throw new ArgumentException ("Keep-Alive and Close may not be set with this property");
 248
 249                                 if (keepAlive)
 250                                         value = value + ", Keep-Alive";
 251
 252                                 webHeaders.RemoveAndAdd ("Connection", value);
 253                         }
 254                 }
 255
 256                 public override string ConnectionGroupName {
 257                         get { return connectionGroup; }
 258                         set { connectionGroup = value; }
 259                 }
 260
 261                 public override long ContentLength {
 262                         get { return contentLength; }
 263                         set {
 264                                 CheckRequestStarted ();
 265                                 if (value < 0)
 266                                         throw new ArgumentOutOfRangeException ("value", "Content-Length must be >= 0");
 267
 268                                 contentLength = value;
 269                         }
 270                 }
 271
 272                 internal long InternalContentLength {
 273                         set { contentLength = value; }
 274                 }
 275
 276                 internal bool ThrowOnError { get; set; }
 277
 278                 public override string ContentType {
 279                         get { return webHeaders ["Content-Type"]; }
 280                         set {
 281                                 if (value == null || value.Trim().Length == 0) {
 282                                         webHeaders.RemoveInternal ("Content-Type");
 283                                         return;
 284                                 }
 285                                 webHeaders.RemoveAndAdd ("Content-Type", value);
 286                         }
 287                 }
 288
 289                 public HttpContinueDelegate ContinueDelegate {
 290                         get { return continueDelegate; }
 291                         set { continueDelegate = value; }
 292                 }
 293
 294                 public CookieContainer CookieContainer {
 295                         get { return cookieContainer; }
 296                         set { cookieContainer = value; }
 297                 }
 298
 299                 public override ICredentials Credentials {
 300                         get { return credentials; }
 301                         set { credentials = value; }
 302                 }
 303 #if NET_4_0
 304                 public DateTime Date {
 305                         get {
 306                                 string date = webHeaders ["Date"];
 307                                 if (date == null)
 308                                         return DateTime.MinValue;
 309                                 return DateTime.ParseExact (date, "r", CultureInfo.InvariantCulture).ToLocalTime ();
 310                         }
 311                         set {
 312                                 if (value.Equals (DateTime.MinValue))
 313                                         webHeaders.RemoveInternal ("Date");
 314                                 else
 315                                         webHeaders.RemoveAndAdd ("Date", value.ToUniversalTime ().ToString ("r", CultureInfo.InvariantCulture));
 316                         }
 317                 }
 318 #endif
 319                 [MonoTODO]
 320                 public static new RequestCachePolicy DefaultCachePolicy
 321                 {
 322                         get {
 323                                 throw GetMustImplement ();
 324                         }
 325                         set {
 326                                 throw GetMustImplement ();
 327                         }
 328                 }
 329
 330                 [MonoTODO]
 331                 public static int DefaultMaximumErrorResponseLength
 332                 {
 333                         get {
 334                                 throw GetMustImplement ();
 335                         }
 336                         set {
 337                                 throw GetMustImplement ();
 338                         }
 339                 }
 340
 341                 public string Expect {
 342                         get { return webHeaders ["Expect"]; }
 343                         set {
 344                                 CheckRequestStarted ();
 345                                 string val = value;
 346                                 if (val != null)
 347                                         val = val.Trim ().ToLower ();
 348
 349                                 if (val == null || val.Length == 0) {
 350                                         webHeaders.RemoveInternal ("Expect");
 351                                         return;
 352                                 }
 353
 354                                 if (val == "100-continue")
 355                                         throw new ArgumentException ("100-Continue cannot be set with this property.",
 356                                                                      "value");
 357                                 webHeaders.RemoveAndAdd ("Expect", value);
 358                         }
 359                 }
 360
 361                 public bool HaveResponse {
 362                         get { return haveResponse; }
 363                 }
 364
 365                 public override WebHeaderCollection Headers {
 366                         get { return webHeaders; }
 367                         set {
 368                                 CheckRequestStarted ();
 369                                 WebHeaderCollection newHeaders = new WebHeaderCollection (WebHeaderCollection.HeaderInfo.Request);
 370                                 int count = value.Count;
 371                                 for (int i = 0; i < count; i++)
 372                                         newHeaders.Add (value.GetKey (i), value.Get (i));
 373
 374                                 webHeaders = newHeaders;
 375                         }
 376                 }
 377
 378 #if NET_4_0
 379                 public
 380 #else
 381                 internal
 382 #endif
 383                 string Host {
 384                         get {
 385                                 if (host == null)
 386                                         return actualUri.Authority;
 387                                 return host;
 388                         }
 389                         set {
 390                                 if (value == null)
 391                                         throw new ArgumentNullException ("value");
 392
 393                                 if (!CheckValidHost (actualUri.Scheme, value))
 394                                         throw new ArgumentException ("Invalid host: " + value);
 395
 396                                 host = value;
 397                         }
 398                 }
 399
 400                 static bool CheckValidHost (string scheme, string val)
 401                 {
 402                         if (val.Length == 0)
 403                                 return false;
 404
 405                         if (val [0] == '.')
 406                                 return false;
 407
 408                         int idx = val.IndexOf ('/');
 409                         if (idx >= 0)
 410                                 return false;
 411
 412                         string u = scheme + "://" + val + "/";
 413                         return Uri.IsWellFormedUriString (u, UriKind.Absolute);
 414                 }
 415
 416                 public DateTime IfModifiedSince {
 417                         get {
 418                                 string str = webHeaders ["If-Modified-Since"];
 419                                 if (str == null)
 420                                         return DateTime.Now;
 421                                 try {
 422                                         return MonoHttpDate.Parse (str);
 423                                 } catch (Exception) {
 424                                         return DateTime.Now;
 425                                 }
 426                         }
 427                         set {
 428                                 CheckRequestStarted ();
 429                                 // rfc-1123 pattern
 430                                 webHeaders.SetInternal ("If-Modified-Since",
 431                                         value.ToUniversalTime ().ToString ("r", null));
 432                                 // TODO: check last param when using different locale
 433                         }
 434                 }
 435
 436                 public bool KeepAlive {
 437                         get {
 438                                 return keepAlive;
 439                         }
 440                         set {
 441                                 keepAlive = value;
 442                         }
 443                 }
 444
 445                 public int MaximumAutomaticRedirections {
 446                         get { return maxAutoRedirect; }
 447                         set {
 448                                 if (value <= 0)
 449                                         throw new ArgumentException ("Must be > 0", "value");
 450
 451                                 maxAutoRedirect = value;
 452                         }
 453                 }
 454
 455                 [MonoTODO ("Use this")]
 456                 public int MaximumResponseHeadersLength {
 457                         get { return maxResponseHeadersLength; }
 458                         set { maxResponseHeadersLength = value; }
 459                 }
 460
 461                 [MonoTODO ("Use this")]
 462                 public static int DefaultMaximumResponseHeadersLength {
 463                         get { return defaultMaxResponseHeadersLength; }
 464                         set { defaultMaxResponseHeadersLength = value; }
 465                 }
 466
 467                 public  int ReadWriteTimeout {
 468                         get { return readWriteTimeout; }
 469                         set {
 470                                 if (requestSent)
 471                                         throw new InvalidOperationException ("The request has already been sent.");
 472
 473                                 if (value < -1)
 474                                         throw new ArgumentOutOfRangeException ("value", "Must be >= -1");
 475
 476                                 readWriteTimeout = value;
 477                         }
 478                 }
 479
 480                 public string MediaType {
 481                         get { return mediaType; }
 482                         set {
 483                                 mediaType = value;
 484                         }
 485                 }
 486
 487                 public override string Method {
 488                         get { return this.method; }
 489                         set {
 490                                 if (value == null || value.Trim () == "")
 491                                         throw new ArgumentException ("not a valid method");
 492
 493                                 method = value.ToUpperInvariant ();
 494                                 if (method != "HEAD" && method != "GET" && method != "POST" && method != "PUT" &&
 495                                         method != "DELETE" && method != "CONNECT" && method != "TRACE" &&
 496                                         method != "MKCOL") {
 497                                         method = value;
 498                                 }
 499                         }
 500                 }
 501
 502                 public bool Pipelined {
 503                         get { return pipelined; }
 504                         set { pipelined = value; }
 505                 }
 506
 507                 public override bool PreAuthenticate {
 508                         get { return preAuthenticate; }
 509                         set { preAuthenticate = value; }
 510                 }
 511
 512                 public Version ProtocolVersion {
 513                         get { return version; }
 514                         set {
 515                                 if (value != HttpVersion.Version10 && value != HttpVersion.Version11)
 516                                         throw new ArgumentException ("value");
 517
 518                                 force_version = true;
 519                                 version = value;
 520                         }
 521                 }
 522
 523                 public override IWebProxy Proxy {
 524                         get { return proxy; }
 525                         set {
 526                                 CheckRequestStarted ();
 527                                 proxy = value;
 528                                 servicePoint = null; // we may need a new one
 529                         }
 530                 }
 531
 532                 public string Referer {
 533                         get { return webHeaders ["Referer"]; }
 534                         set {
 535                                 CheckRequestStarted ();
 536                                 if (value == null || value.Trim().Length == 0) {
 537                                         webHeaders.RemoveInternal ("Referer");
 538                                         return;
 539                                 }
 540                                 webHeaders.SetInternal ("Referer", value);
 541                         }
 542                 }
 543
 544                 public override Uri RequestUri {
 545                         get { return requestUri; }
 546                 }
 547
 548                 public bool SendChunked {
 549                         get { return sendChunked; }
 550                         set {
 551                                 CheckRequestStarted ();
 552                                 sendChunked = value;
 553                         }
 554                 }
 555
 556                 public ServicePoint ServicePoint {
 557                         get { return GetServicePoint (); }
 558                 }
 559
 560                 internal ServicePoint ServicePointNoLock {
 561                         get { return servicePoint; }
 562                 }
 563 #if NET_4_5 || MOBILE
 564                 [MonoTODO ("for portable library support")]
 565                 public bool SupportsCookieContainer {
 566                         get {
 567                                 throw new NotImplementedException ();
 568                         }
 569                 }
 570 #endif
 571                 public override int Timeout {
 572                         get { return timeout; }
 573                         set {
 574                                 if (value < -1)
 575                                         throw new ArgumentOutOfRangeException ("value");
 576
 577                                 timeout = value;
 578                         }
 579                 }
 580
 581                 public string TransferEncoding {
 582                         get { return webHeaders ["Transfer-Encoding"]; }
 583                         set {
 584                                 CheckRequestStarted ();
 585                                 string val = value;
 586                                 if (val != null)
 587                                         val = val.Trim ().ToLower ();
 588
 589                                 if (val == null || val.Length == 0) {
 590                                         webHeaders.RemoveInternal ("Transfer-Encoding");
 591                                         return;
 592                                 }
 593
 594                                 if (val == "chunked")
 595                                         throw new ArgumentException ("Chunked encoding must be set with the SendChunked property");
 596
 597                                 if (!sendChunked)
 598                                         throw new ArgumentException ("SendChunked must be True", "value");
 599
 600                                 webHeaders.RemoveAndAdd ("Transfer-Encoding", value);
 601                         }
 602                 }
 603
 604                 public override bool UseDefaultCredentials
 605                 {
 606                         get { return CredentialCache.DefaultCredentials == Credentials; }
 607                         set { Credentials = value ? CredentialCache.DefaultCredentials : null; }
 608                 }
 609
 610                 public string UserAgent {
 611                         get { return webHeaders ["User-Agent"]; }
 612                         set { webHeaders.SetInternal ("User-Agent", value); }
 613                 }
 614
 615                 bool unsafe_auth_blah;
 616                 public bool UnsafeAuthenticatedConnectionSharing
 617                 {
 618                         get { return unsafe_auth_blah; }
 619                         set { unsafe_auth_blah = value; }
 620                 }
 621
 622                 internal bool GotRequestStream {
 623                         get { return gotRequestStream; }
 624                 }
 625
 626                 internal bool ExpectContinue {
 627                         get { return expectContinue; }
 628                         set { expectContinue = value; }
 629                 }
 630
 631                 internal Uri AuthUri {
 632                         get { return actualUri; }
 633                 }
 634
 635                 internal bool ProxyQuery {
 636                         get { return servicePoint.UsesProxy && !servicePoint.UseConnect; }
 637                 }
 638
 639                 // Methods
 640
 641                 internal ServicePoint GetServicePoint ()
 642                 {
 643                         lock (locker) {
 644                                 if (hostChanged || servicePoint == null) {
 645                                         servicePoint = ServicePointManager.FindServicePoint (actualUri, proxy);
 646                                         hostChanged = false;
 647                                 }
 648                         }
 649
 650                         return servicePoint;
 651                 }
 652
 653                 public void AddRange (int range)
 654                 {
 655                         AddRange ("bytes", (long) range);
 656                 }
 657
 658                 public void AddRange (int from, int to)
 659                 {
 660                         AddRange ("bytes", (long) from, (long) to);
 661                 }
 662
 663                 public void AddRange (string rangeSpecifier, int range)
 664                 {
 665                         AddRange (rangeSpecifier, (long) range);
 666                 }
 667
 668                 public void AddRange (string rangeSpecifier, int from, int to)
 669                 {
 670                         AddRange (rangeSpecifier, (long) from, (long) to);
 671                 }
 672 #if NET_4_0
 673                 public
 674 #else
 675                 internal
 676 #endif
 677                 void AddRange (long range)
 678                 {
 679                         AddRange ("bytes", (long) range);
 680                 }
 681
 682 #if NET_4_0
 683                 public
 684 #else
 685                 internal
 686 #endif
 687                 void AddRange (long from, long to)
 688                 {
 689                         AddRange ("bytes", from, to);
 690                 }
 691
 692 #if NET_4_0
 693                 public
 694 #else
 695                 internal
 696 #endif
 697                 void AddRange (string rangeSpecifier, long range)
 698                 {
 699                         if (rangeSpecifier == null)
 700                                 throw new ArgumentNullException ("rangeSpecifier");
 701                         if (!WebHeaderCollection.IsHeaderValue (rangeSpecifier))
 702                                 throw new ArgumentException ("Invalid range specifier", "rangeSpecifier");
 703
 704                         string r = webHeaders ["Range"];
 705                         if (r == null)
 706                                 r = rangeSpecifier + "=";
 707                         else {
 708                                 string old_specifier = r.Substring (0, r.IndexOf ('='));
 709                                 if (String.Compare (old_specifier, rangeSpecifier, StringComparison.OrdinalIgnoreCase) != 0)
 710                                         throw new InvalidOperationException ("A different range specifier is already in use");
 711                                 r += ",";
 712                         }
 713
 714                         string n = range.ToString (CultureInfo.InvariantCulture);
 715                         if (range < 0)
 716                                 r = r + "0" + n;
 717                         else
 718                                 r = r + n + "-";
 719                         webHeaders.RemoveAndAdd ("Range", r);
 720                 }
 721
 722 #if NET_4_0
 723                 public
 724 #else
 725                 internal
 726 #endif
 727                 void AddRange (string rangeSpecifier, long from, long to)
 728                 {
 729                         if (rangeSpecifier == null)
 730                                 throw new ArgumentNullException ("rangeSpecifier");
 731                         if (!WebHeaderCollection.IsHeaderValue (rangeSpecifier))
 732                                 throw new ArgumentException ("Invalid range specifier", "rangeSpecifier");
 733                         if (from > to || from < 0)
 734                                 throw new ArgumentOutOfRangeException ("from");
 735                         if (to < 0)
 736                                 throw new ArgumentOutOfRangeException ("to");
 737
 738                         string r = webHeaders ["Range"];
 739                         if (r == null)
 740                                 r = rangeSpecifier + "=";
 741                         else
 742                                 r += ",";
 743
 744                         r = String.Format ("{0}{1}-{2}", r, from, to);
 745                         webHeaders.RemoveAndAdd ("Range", r);
 746                 }
 747
 748
 749                 public override IAsyncResult BeginGetRequestStream (AsyncCallback callback, object state)
 750                 {
 751                         if (Aborted)
 752                                 throw new WebException ("The request was canceled.", WebExceptionStatus.RequestCanceled);
 753
 754                         bool send = !(method == "GET" || method == "CONNECT" || method == "HEAD" ||
 755                                         method == "TRACE");
 756                         if (method == null || !send)
 757                                 throw new ProtocolViolationException ("Cannot send data when method is: " + method);
 758
 759                         if (contentLength == -1 && !sendChunked && !allowBuffering && KeepAlive)
 760                                 throw new ProtocolViolationException ("Content-Length not set");
 761
 762                         string transferEncoding = TransferEncoding;
 763                         if (!sendChunked && transferEncoding != null && transferEncoding.Trim () != "")
 764                                 throw new ProtocolViolationException ("SendChunked should be true.");
 765
 766                         lock (locker)
 767                         {
 768                                 if (getResponseCalled)
 769                                         throw new InvalidOperationException ("The operation cannot be performed once the request has been submitted.");
 770
 771                                 if (asyncWrite != null) {
 772                                         throw new InvalidOperationException ("Cannot re-call start of asynchronous " +
 773                                                                 "method while a previous call is still in progress.");
 774                                 }
 775
 776                                 asyncWrite = new WebAsyncResult (this, callback, state);
 777                                 initialMethod = method;
 778                                 if (haveRequest) {
 779                                         if (writeStream != null) {
 780                                                 asyncWrite.SetCompleted (true, writeStream);
 781                                                 asyncWrite.DoCallback ();
 782                                                 return asyncWrite;
 783                                         }
 784                                 }
 785
 786                                 gotRequestStream = true;
 787                                 WebAsyncResult result = asyncWrite;
 788                                 if (!requestSent) {
 789                                         requestSent = true;
 790                                         redirects = 0;
 791                                         servicePoint = GetServicePoint ();
 792                                         abortHandler = servicePoint.SendRequest (this, connectionGroup);
 793                                 }
 794                                 return result;
 795                         }
 796                 }
 797
 798                 public override Stream EndGetRequestStream (IAsyncResult asyncResult)
 799                 {
 800                         if (asyncResult == null)
 801                                 throw new ArgumentNullException ("asyncResult");
 802
 803                         WebAsyncResult result = asyncResult as WebAsyncResult;
 804                         if (result == null)
 805                                 throw new ArgumentException ("Invalid IAsyncResult");
 806
 807                         asyncWrite = result;
 808                         result.WaitUntilComplete ();
 809
 810                         Exception e = result.Exception;
 811                         if (e != null)
 812                                 throw e;
 813
 814                         return result.WriteStream;
 815                 }
 816
 817                 public override Stream GetRequestStream()
 818                 {
 819                         IAsyncResult asyncResult = asyncWrite;
 820                         if (asyncResult == null) {
 821                                 asyncResult = BeginGetRequestStream (null, null);
 822                                 asyncWrite = (WebAsyncResult) asyncResult;
 823                         }
 824
 825                         if (!asyncResult.IsCompleted && !asyncResult.AsyncWaitHandle.WaitOne (timeout, false)) {
 826                                 Abort ();
 827                                 throw new WebException ("The request timed out", WebExceptionStatus.Timeout);
 828                         }
 829
 830                         return EndGetRequestStream (asyncResult);
 831                 }
 832
 833                 void CheckIfForceWrite ()
 834                 {
 835                         if (writeStream == null || writeStream.RequestWritten || !InternalAllowBuffering)
 836                                 return;
 837 #if NET_4_0
 838                         if (contentLength < 0 && writeStream.CanWrite == true && writeStream.WriteBufferLength < 0)
 839                                 return;
 840
 841                         if (contentLength < 0 && writeStream.WriteBufferLength >= 0)
 842                                 InternalContentLength = writeStream.WriteBufferLength;
 843 #else
 844                         if (contentLength < 0 && writeStream.CanWrite == true)
 845                                 return;
 846 #endif
 847
 848                         // This will write the POST/PUT if the write stream already has the expected
 849                         // amount of bytes in it (ContentLength) (bug #77753) or if the write stream
 850                         // contains data and it has been closed already (xamarin bug #1512).
 851
 852                         if (writeStream.WriteBufferLength == contentLength || (contentLength == -1 && writeStream.CanWrite == false))
 853                                 writeStream.WriteRequest ();
 854                 }
 855
 856                 public override IAsyncResult BeginGetResponse (AsyncCallback callback, object state)
 857                 {
 858                         if (Aborted)
 859                                 throw new WebException ("The request was canceled.", WebExceptionStatus.RequestCanceled);
 860
 861                         if (method == null)
 862                                 throw new ProtocolViolationException ("Method is null.");
 863
 864                         string transferEncoding = TransferEncoding;
 865                         if (!sendChunked && transferEncoding != null && transferEncoding.Trim () != "")
 866                                 throw new ProtocolViolationException ("SendChunked should be true.");
 867
 868                         Monitor.Enter (locker);
 869                         getResponseCalled = true;
 870                         if (asyncRead != null && !haveResponse) {
 871                                 Monitor.Exit (locker);
 872                                 throw new InvalidOperationException ("Cannot re-call start of asynchronous " +
 873                                                         "method while a previous call is still in progress.");
 874                         }
 875
 876                         CheckIfForceWrite ();
 877                         asyncRead = new WebAsyncResult (this, callback, state);
 878                         WebAsyncResult aread = asyncRead;
 879                         initialMethod = method;
 880                         if (haveResponse) {
 881                                 Exception saved = saved_exc;
 882                                 if (webResponse != null) {
 883                                         Monitor.Exit (locker);
 884                                         if (saved == null) {
 885                                                 aread.SetCompleted (true, webResponse);
 886                                         } else {
 887                                                 aread.SetCompleted (true, saved);
 888                                         }
 889                                         aread.DoCallback ();
 890                                         return aread;
 891                                 } else if (saved != null) {
 892                                         Monitor.Exit (locker);
 893                                         aread.SetCompleted (true, saved);
 894                                         aread.DoCallback ();
 895                                         return aread;
 896                                 }
 897                         }
 898
 899                         if (!requestSent) {
 900                                 requestSent = true;
 901                                 redirects = 0;
 902                                 servicePoint = GetServicePoint ();
 903                                 abortHandler = servicePoint.SendRequest (this, connectionGroup);
 904                         }
 905
 906                         Monitor.Exit (locker);
 907                         return aread;
 908                 }
 909
 910                 public override WebResponse EndGetResponse (IAsyncResult asyncResult)
 911                 {
 912                         if (asyncResult == null)
 913                                 throw new ArgumentNullException ("asyncResult");
 914
 915                         WebAsyncResult result = asyncResult as WebAsyncResult;
 916                         if (result == null)
 917                                 throw new ArgumentException ("Invalid IAsyncResult", "asyncResult");
 918
 919                         if (!result.WaitUntilComplete (timeout, false)) {
 920                                 Abort ();
 921                                 throw new WebException("The request timed out", WebExceptionStatus.Timeout);
 922                         }
 923
 924                         if (result.GotException)
 925                                 throw result.Exception;
 926
 927                         return result.Response;
 928                 }
 929
 930                 public override WebResponse GetResponse()
 931                 {
 932                         asynchronous = false;
 933                         WebAsyncResult result = (WebAsyncResult) BeginGetResponse (null, null);
 934                         return EndGetResponse (result);
 935                 }
 936
 937                 internal bool asynchronous = true;
 938
 939                 internal bool FinishedReading {
 940                         get { return finished_reading; }
 941                         set { finished_reading = value; }
 942                 }
 943
 944                 internal bool Aborted {
 945                         get { return Interlocked.CompareExchange (ref aborted, 0, 0) == 1; }
 946                 }
 947
 948                 public override void Abort ()
 949                 {
 950                         if (Interlocked.CompareExchange (ref aborted, 1, 0) == 1)
 951                                 return;
 952
 953                         if (haveResponse && finished_reading)
 954                                 return;
 955
 956                         haveResponse = true;
 957                         if (abortHandler != null) {
 958                                 try {
 959                                         abortHandler (this, EventArgs.Empty);
 960                                 } catch (Exception) {}
 961                                 abortHandler = null;
 962                         }
 963
 964                         if (asyncWrite != null) {
 965                                 WebAsyncResult r = asyncWrite;
 966                                 if (!r.IsCompleted) {
 967                                         try {
 968                                                 WebException wexc = new WebException ("Aborted.", WebExceptionStatus.RequestCanceled);
 969                                                 r.SetCompleted (false, wexc);
 970                                                 r.DoCallback ();
 971                                         } catch {}
 972                                 }
 973                                 asyncWrite = null;
 974                         }
 975
 976                         if (asyncRead != null) {
 977                                 WebAsyncResult r = asyncRead;
 978                                 if (!r.IsCompleted) {
 979                                         try {
 980                                                 WebException wexc = new WebException ("Aborted.", WebExceptionStatus.RequestCanceled);
 981                                                 r.SetCompleted (false, wexc);
 982                                                 r.DoCallback ();
 983                                         } catch {}
 984                                 }
 985                                 asyncRead = null;
 986                         }
 987
 988                         if (writeStream != null) {
 989                                 try {
 990                                         writeStream.Close ();
 991                                         writeStream = null;
 992                                 } catch {}
 993                         }
 994
 995                         if (webResponse != null) {
 996                                 try {
 997                                         webResponse.Close ();
 998                                         webResponse = null;
 999                                 } catch {}
1000                         }
1001                 }
1002
1003                 void ISerializable.GetObjectData (SerializationInfo serializationInfo,
1004                                                   StreamingContext streamingContext)
1005                 {
1006                         GetObjectData (serializationInfo, streamingContext);
1007                 }
1008
1009                 protected override void GetObjectData (SerializationInfo serializationInfo,
1010                         StreamingContext streamingContext)
1011                 {
1012                         SerializationInfo info = serializationInfo;
1013
1014                         info.AddValue ("requestUri", requestUri, typeof (Uri));
1015                         info.AddValue ("actualUri", actualUri, typeof (Uri));
1016                         info.AddValue ("allowAutoRedirect", allowAutoRedirect);
1017                         info.AddValue ("allowBuffering", allowBuffering);
1018                         info.AddValue ("certificates", certificates, typeof (X509CertificateCollection));
1019                         info.AddValue ("connectionGroup", connectionGroup);
1020                         info.AddValue ("contentLength", contentLength);
1021                         info.AddValue ("webHeaders", webHeaders, typeof (WebHeaderCollection));
1022                         info.AddValue ("keepAlive", keepAlive);
1023                         info.AddValue ("maxAutoRedirect", maxAutoRedirect);
1024                         info.AddValue ("mediaType", mediaType);
1025                         info.AddValue ("method", method);
1026                         info.AddValue ("initialMethod", initialMethod);
1027                         info.AddValue ("pipelined", pipelined);
1028                         info.AddValue ("version", version, typeof (Version));
1029                         info.AddValue ("proxy", proxy, typeof (IWebProxy));
1030                         info.AddValue ("sendChunked", sendChunked);
1031                         info.AddValue ("timeout", timeout);
1032                         info.AddValue ("redirects", redirects);
1033                         info.AddValue ("host", host);
1034                 }
1035
1036                 void CheckRequestStarted ()
1037                 {
1038                         if (requestSent)
1039                                 throw new InvalidOperationException ("request started");
1040                 }
1041
1042                 internal void DoContinueDelegate (int statusCode, WebHeaderCollection headers)
1043                 {
1044                         if (continueDelegate != null)
1045                                 continueDelegate (statusCode, headers);
1046                 }
1047
1048                 bool Redirect (WebAsyncResult result, HttpStatusCode code)
1049                 {
1050                         redirects++;
1051                         Exception e = null;
1052                         string uriString = null;
1053
1054                         switch (code) {
1055                         case HttpStatusCode.Ambiguous: // 300
1056                                 e = new WebException ("Ambiguous redirect.");
1057                                 break;
1058                         case HttpStatusCode.MovedPermanently: // 301
1059                         case HttpStatusCode.Redirect: // 302
1060                         case HttpStatusCode.TemporaryRedirect: // 307
1061                                 /* MS follows the redirect for POST too
1062                                 if (method != "GET" && method != "HEAD") // 10.3
1063                                         return false;
1064                                 */
1065
1066                                 contentLength = -1;
1067                                 bodyBufferLength = 0;
1068                                 bodyBuffer = null;
1069                                 if (code != HttpStatusCode.TemporaryRedirect)
1070                                         method = "GET";
1071                                 uriString = webResponse.Headers ["Location"];
1072                                 break;
1073                         case HttpStatusCode.SeeOther: //303
1074                                 method = "GET";
1075                                 uriString = webResponse.Headers ["Location"];
1076                                 break;
1077                         case HttpStatusCode.NotModified: // 304
1078                                 return false;
1079                         case HttpStatusCode.UseProxy: // 305
1080                                 e = new NotImplementedException ("Proxy support not available.");
1081                                 break;
1082                         case HttpStatusCode.Unused: // 306
1083                         default:
1084                                 e = new ProtocolViolationException ("Invalid status code: " + (int) code);
1085                                 break;
1086                         }
1087
1088                         if (e != null)
1089                                 throw e;
1090
1091                         if (uriString == null)
1092                                 throw new WebException ("No Location header found for " + (int) code,
1093                                                         WebExceptionStatus.ProtocolError);
1094
1095                         Uri prev = actualUri;
1096                         try {
1097                                 actualUri = new Uri (actualUri, uriString);
1098                         } catch (Exception) {
1099                                 throw new WebException (String.Format ("Invalid URL ({0}) for {1}",
1100                                                                         uriString, (int) code),
1101                                                                         WebExceptionStatus.ProtocolError);
1102                         }
1103
1104                         hostChanged = (actualUri.Scheme != prev.Scheme || Host != prev.Authority);
1105                         return true;
1106                 }
1107
1108                 string GetHeaders ()
1109                 {
1110                         bool continue100 = false;
1111                         if (sendChunked) {
1112                                 continue100 = true;
1113                                 webHeaders.RemoveAndAdd ("Transfer-Encoding", "chunked");
1114                                 webHeaders.RemoveInternal ("Content-Length");
1115                         } else if (contentLength != -1) {
1116                                 if (ntlm_auth_state != NtlmAuthState.Challenge) {
1117                                         if (contentLength > 0)
1118                                                 continue100 = true;
1119
1120                                         webHeaders.SetInternal ("Content-Length", contentLength.ToString ());
1121                                 } else {
1122                                         webHeaders.SetInternal ("Content-Length", "0");
1123                                 }
1124                                 webHeaders.RemoveInternal ("Transfer-Encoding");
1125                         } else {
1126                                 webHeaders.RemoveInternal ("Content-Length");
1127                         }
1128
1129                         if (actualVersion == HttpVersion.Version11 && continue100 &&
1130                             servicePoint.SendContinue) { // RFC2616 8.2.3
1131                                 webHeaders.RemoveAndAdd ("Expect" , "100-continue");
1132                                 expectContinue = true;
1133                         } else {
1134                                 webHeaders.RemoveInternal ("Expect");
1135                                 expectContinue = false;
1136                         }
1137
1138                         bool proxy_query = ProxyQuery;
1139                         string connectionHeader = (proxy_query) ? "Proxy-Connection" : "Connection";
1140                         webHeaders.RemoveInternal ((!proxy_query) ? "Proxy-Connection" : "Connection");
1141                         Version proto_version = servicePoint.ProtocolVersion;
1142                         bool spoint10 = (proto_version == null || proto_version == HttpVersion.Version10);
1143
1144                         if (keepAlive && (version == HttpVersion.Version10 || spoint10)) {
1145                                 webHeaders.RemoveAndAdd (connectionHeader, "keep-alive");
1146                         } else if (!keepAlive && version == HttpVersion.Version11) {
1147                                 webHeaders.RemoveAndAdd (connectionHeader, "close");
1148                         }
1149
1150                         webHeaders.SetInternal ("Host", Host);
1151                         if (cookieContainer != null) {
1152                                 string cookieHeader = cookieContainer.GetCookieHeader (actualUri);
1153                                 if (cookieHeader != "")
1154                                         webHeaders.RemoveAndAdd ("Cookie", cookieHeader);
1155                                 else
1156                                         webHeaders.RemoveInternal ("Cookie");
1157                         }
1158
1159                         string accept_encoding = null;
1160                         if ((auto_decomp & DecompressionMethods.GZip) != 0)
1161                                 accept_encoding = "gzip";
1162                         if ((auto_decomp & DecompressionMethods.Deflate) != 0)
1163                                 accept_encoding = accept_encoding != null ? "gzip, deflate" : "deflate";
1164                         if (accept_encoding != null)
1165                                 webHeaders.RemoveAndAdd ("Accept-Encoding", accept_encoding);
1166
1167                         if (!usedPreAuth && preAuthenticate)
1168                                 DoPreAuthenticate ();
1169
1170                         return webHeaders.ToString ();
1171                 }
1172
1173                 void DoPreAuthenticate ()
1174                 {
1175                         bool isProxy = (proxy != null && !proxy.IsBypassed (actualUri));
1176                         ICredentials creds = (!isProxy || credentials != null) ? credentials : proxy.Credentials;
1177                         Authorization auth = AuthenticationManager.PreAuthenticate (this, creds);
1178                         if (auth == null)
1179                                 return;
1180
1181                         webHeaders.RemoveInternal ("Proxy-Authorization");
1182                         webHeaders.RemoveInternal ("Authorization");
1183                         string authHeader = (isProxy && credentials == null) ? "Proxy-Authorization" : "Authorization";
1184                         webHeaders [authHeader] = auth.Message;
1185                         usedPreAuth = true;
1186                 }
1187
1188                 internal void SetWriteStreamError (WebExceptionStatus status, Exception exc)
1189                 {
1190                         if (Aborted)
1191                                 return;
1192
1193                         WebAsyncResult r = asyncWrite;
1194                         if (r == null)
1195                                 r = asyncRead;
1196
1197                         if (r != null) {
1198                                 string msg;
1199                                 WebException wex;
1200                                 if (exc == null) {
1201                                         msg = "Error: " + status;
1202                                         wex = new WebException (msg, status);
1203                                 } else {
1204                                         msg = String.Format ("Error: {0} ({1})", status, exc.Message);
1205                                         wex = new WebException (msg, exc, status);
1206                                 }
1207                                 r.SetCompleted (false, wex);
1208                                 r.DoCallback ();
1209                         }
1210                 }
1211
1212                 internal void SendRequestHeaders (bool propagate_error)
1213                 {
1214                         StringBuilder req = new StringBuilder ();
1215                         string query;
1216                         if (!ProxyQuery) {
1217                                 query = actualUri.PathAndQuery;
1218                         } else {
1219                                 query = String.Format ("{0}://{1}{2}",  actualUri.Scheme,
1220                                                                         Host,
1221                                                                         actualUri.PathAndQuery);
1222                         }
1223
1224                         if (!force_version && servicePoint.ProtocolVersion != null && servicePoint.ProtocolVersion < version) {
1225                                 actualVersion = servicePoint.ProtocolVersion;
1226                         } else {
1227                                 actualVersion = version;
1228                         }
1229
1230                         req.AppendFormat ("{0} {1} HTTP/{2}.{3}\r\n", method, query,
1231                                                                 actualVersion.Major, actualVersion.Minor);
1232                         req.Append (GetHeaders ());
1233                         string reqstr = req.ToString ();
1234                         byte [] bytes = Encoding.UTF8.GetBytes (reqstr);
1235                         try {
1236                                 writeStream.SetHeaders (bytes);
1237                         } catch (WebException wexc) {
1238                                 SetWriteStreamError (wexc.Status, wexc);
1239                                 if (propagate_error)
1240                                         throw;
1241                         } catch (Exception exc) {
1242                                 SetWriteStreamError (WebExceptionStatus.SendFailure, exc);
1243                                 if (propagate_error)
1244                                         throw;
1245                         }
1246                 }
1247
1248                 internal void SetWriteStream (WebConnectionStream stream)
1249                 {
1250                         if (Aborted)
1251                                 return;
1252
1253                         writeStream = stream;
1254                         if (bodyBuffer != null) {
1255                                 webHeaders.RemoveInternal ("Transfer-Encoding");
1256                                 contentLength = bodyBufferLength;
1257                                 writeStream.SendChunked = false;
1258                         }
1259
1260                         SendRequestHeaders (false);
1261
1262                         haveRequest = true;
1263
1264                         if (bodyBuffer != null) {
1265                                 // The body has been written and buffered. The request "user"
1266                                 // won't write it again, so we must do it.
1267                                 if (ntlm_auth_state != NtlmAuthState.Challenge) {
1268                                         writeStream.Write (bodyBuffer, 0, bodyBufferLength);
1269                                         bodyBuffer = null;
1270                                         writeStream.Close ();
1271                                 }
1272                         } else if (method != "HEAD" && method != "GET" && method != "MKCOL" && method != "CONNECT" &&
1273                                         method != "TRACE") {
1274                                 if (getResponseCalled && !writeStream.RequestWritten)
1275                                         writeStream.WriteRequest ();
1276                         }
1277
1278                         if (asyncWrite != null) {
1279                                 asyncWrite.SetCompleted (false, stream);
1280                                 asyncWrite.DoCallback ();
1281                                 asyncWrite = null;
1282                         }
1283                 }
1284
1285                 internal void SetResponseError (WebExceptionStatus status, Exception e, string where)
1286                 {
1287                         if (Aborted)
1288                                 return;
1289                         lock (locker) {
1290                         string msg = String.Format ("Error getting response stream ({0}): {1}", where, status);
1291                         WebAsyncResult r = asyncRead;
1292                         if (r == null)
1293                                 r = asyncWrite;
1294
1295                         WebException wexc;
1296                         if (e is WebException) {
1297                                 wexc = (WebException) e;
1298                         } else {
1299                                 wexc = new WebException (msg, e, status, null);
1300                         }
1301                         if (r != null) {
1302                                 if (!r.IsCompleted) {
1303                                         r.SetCompleted (false, wexc);
1304                                         r.DoCallback ();
1305                                 } else if (r == asyncWrite) {
1306                                         saved_exc = wexc;
1307                                 }
1308                                 haveResponse = true;
1309                                 asyncRead = null;
1310                                 asyncWrite = null;
1311                         } else {
1312                                 haveResponse = true;
1313                                 saved_exc = wexc;
1314                         }
1315                         }
1316                 }
1317
1318                 void CheckSendError (WebConnectionData data)
1319                 {
1320                         // Got here, but no one called GetResponse
1321                         int status = data.StatusCode;
1322                         if (status < 400 || status == 401 || status == 407)
1323                                 return;
1324
1325                         if (writeStream != null && asyncRead == null && !writeStream.CompleteRequestWritten) {
1326                                 // The request has not been completely sent and we got here!
1327                                 // We should probably just close and cause an error in any case,
1328                                 saved_exc = new WebException (data.StatusDescription, null, WebExceptionStatus.ProtocolError, webResponse);
1329                                 if (allowBuffering || sendChunked || writeStream.totalWritten >= contentLength) {
1330                                         webResponse.ReadAll ();
1331                                 } else {
1332                                         writeStream.IgnoreIOErrors = true;
1333                                 }
1334                         }
1335                 }
1336
1337                 void HandleNtlmAuth (WebAsyncResult r)
1338                 {
1339                         WebConnectionStream wce = webResponse.GetResponseStream () as WebConnectionStream;
1340                         if (wce != null) {
1341                                 WebConnection cnc = wce.Connection;
1342                                 cnc.PriorityRequest = this;
1343                                 bool isProxy = (proxy != null && !proxy.IsBypassed (actualUri));
1344                                 ICredentials creds = (!isProxy) ? credentials : proxy.Credentials;
1345                                 if (creds != null) {
1346                                         cnc.NtlmCredential = creds.GetCredential (requestUri, "NTLM");
1347                                         cnc.UnsafeAuthenticatedConnectionSharing = unsafe_auth_blah;
1348                                 }
1349                         }
1350                         r.Reset ();
1351                         finished_reading = false;
1352                         haveResponse = false;
1353                         webResponse.ReadAll ();
1354                         webResponse = null;
1355                 }
1356
1357                 internal void SetResponseData (WebConnectionData data)
1358                 {
1359                         lock (locker) {
1360                         if (Aborted) {
1361                                 if (data.stream != null)
1362                                         data.stream.Close ();
1363                                 return;
1364                         }
1365
1366                         WebException wexc = null;
1367                         try {
1368                                 webResponse = new HttpWebResponse (actualUri, method, data, cookieContainer);
1369                         } catch (Exception e) {
1370                                 wexc = new WebException (e.Message, e, WebExceptionStatus.ProtocolError, null);
1371                                 if (data.stream != null)
1372                                         data.stream.Close ();
1373                         }
1374
1375                         if (wexc == null && (method == "POST" || method == "PUT")) {
1376                                 CheckSendError (data);
1377                                 if (saved_exc != null)
1378                                         wexc = (WebException) saved_exc;
1379                         }
1380
1381                         WebAsyncResult r = asyncRead;
1382
1383                         bool forced = false;
1384                         if (r == null && webResponse != null) {
1385                                 // This is a forced completion (302, 204)...
1386                                 forced = true;
1387                                 r = new WebAsyncResult (null, null);
1388                                 r.SetCompleted (false, webResponse);
1389                         }
1390
1391                         if (r != null) {
1392                                 if (wexc != null) {
1393                                         haveResponse = true;
1394                                         if (!r.IsCompleted)
1395                                                 r.SetCompleted (false, wexc);
1396                                         r.DoCallback ();
1397                                         return;
1398                                 }
1399
1400                                 bool redirected;
1401                                 try {
1402                                         redirected = CheckFinalStatus (r);
1403                                         if (!redirected) {
1404                                                 if (ntlm_auth_state != NtlmAuthState.None && authCompleted && webResponse != null
1405                                                         && (int)webResponse.StatusCode < 400) {
1406                                                         WebConnectionStream wce = webResponse.GetResponseStream () as WebConnectionStream;
1407                                                         if (wce != null) {
1408                                                                 WebConnection cnc = wce.Connection;
1409                                                                 cnc.NtlmAuthenticated = true;
1410                                                         }
1411                                                 }
1412
1413                                                 // clear internal buffer so that it does not
1414                                                 // hold possible big buffer (bug #397627)
1415                                                 if (writeStream != null)
1416                                                         writeStream.KillBuffer ();
1417
1418                                                 haveResponse = true;
1419                                                 r.SetCompleted (false, webResponse);
1420                                                 r.DoCallback ();
1421                                         } else {
1422                                                 if (webResponse != null) {
1423                                                         if (ntlm_auth_state != NtlmAuthState.None) {
1424                                                                 HandleNtlmAuth (r);
1425                                                                 return;
1426                                                         }
1427                                                         webResponse.Close ();
1428                                                 }
1429                                                 finished_reading = false;
1430                                                 haveResponse = false;
1431                                                 webResponse = null;
1432                                                 r.Reset ();
1433                                                 servicePoint = GetServicePoint ();
1434                                                 abortHandler = servicePoint.SendRequest (this, connectionGroup);
1435                                         }
1436                                 } catch (WebException wexc2) {
1437                                         if (forced) {
1438                                                 saved_exc = wexc2;
1439                                                 haveResponse = true;
1440                                         }
1441                                         r.SetCompleted (false, wexc2);
1442                                         r.DoCallback ();
1443                                         return;
1444                                 } catch (Exception ex) {
1445                                         wexc = new WebException (ex.Message, ex, WebExceptionStatus.ProtocolError, null);
1446                                         if (forced) {
1447                                                 saved_exc = wexc;
1448                                                 haveResponse = true;
1449                                         }
1450                                         r.SetCompleted (false, wexc);
1451                                         r.DoCallback ();
1452                                         return;
1453                                 }
1454                         }
1455                         }
1456                 }
1457
1458                 bool CheckAuthorization (WebResponse response, HttpStatusCode code)
1459                 {
1460                         authCompleted = false;
1461                         if (code == HttpStatusCode.Unauthorized && credentials == null)
1462                                 return false;
1463
1464                         bool isProxy = (code == HttpStatusCode.ProxyAuthenticationRequired);
1465                         if (isProxy && (proxy == null || proxy.Credentials == null))
1466                                 return false;
1467
1468                         string [] authHeaders = response.Headers.GetValues_internal ( (isProxy) ? "Proxy-Authenticate" : "WWW-Authenticate", false);
1469                         if (authHeaders == null || authHeaders.Length == 0)
1470                                 return false;
1471
1472                         ICredentials creds = (!isProxy) ? credentials : proxy.Credentials;
1473                         Authorization auth = null;
1474                         foreach (string authHeader in authHeaders) {
1475                                 auth = AuthenticationManager.Authenticate (authHeader, this, creds);
1476                                 if (auth != null)
1477                                         break;
1478                         }
1479                         if (auth == null)
1480                                 return false;
1481                         webHeaders [(isProxy) ? "Proxy-Authorization" : "Authorization"] = auth.Message;
1482                         authCompleted = auth.Complete;
1483                         bool is_ntlm = (auth.Module.AuthenticationType == "NTLM");
1484                         if (is_ntlm)
1485                                 ntlm_auth_state = (NtlmAuthState)((int) ntlm_auth_state + 1);
1486                         return true;
1487                 }
1488
1489                 // Returns true if redirected
1490                 bool CheckFinalStatus (WebAsyncResult result)
1491                 {
1492                         if (result.GotException) {
1493                                 bodyBuffer = null;
1494                                 throw result.Exception;
1495                         }
1496
1497                         Exception throwMe = result.Exception;
1498
1499                         HttpWebResponse resp = result.Response;
1500                         WebExceptionStatus protoError = WebExceptionStatus.ProtocolError;
1501                         HttpStatusCode code = 0;
1502                         if (throwMe == null && webResponse != null) {
1503                                 code = webResponse.StatusCode;
1504                                 if (!authCompleted && ((code == HttpStatusCode.Unauthorized && credentials != null) ||
1505                                      (ProxyQuery && code == HttpStatusCode.ProxyAuthenticationRequired))) {
1506                                         if (!usedPreAuth && CheckAuthorization (webResponse, code)) {
1507                                                 // Keep the written body, so it can be rewritten in the retry
1508                                                 if (InternalAllowBuffering) {
1509                                                         // NTLM: This is to avoid sending data in the 'challenge' request
1510                                                         // We save it in the first request (first 401), don't send anything
1511                                                         // in the challenge request and send it in the response request along
1512                                                         // with the buffers kept form the first request.
1513                                                         if (ntlm_auth_state != NtlmAuthState.Response) {
1514                                                                 bodyBuffer = writeStream.WriteBuffer;
1515                                                                 bodyBufferLength = writeStream.WriteBufferLength;
1516                                                         }
1517                                                         return true;
1518                                                 } else if (method != "PUT" && method != "POST") {
1519                                                         bodyBuffer = null;
1520                                                         return true;
1521                                                 }
1522
1523                                                 if (!ThrowOnError)
1524                                                         return false;
1525
1526                                                 writeStream.InternalClose ();
1527                                                 writeStream = null;
1528                                                 webResponse.Close ();
1529                                                 webResponse = null;
1530                                                 bodyBuffer = null;
1531
1532                                                 throw new WebException ("This request requires buffering " +
1533                                                                         "of data for authentication or " +
1534                                                                         "redirection to be sucessful.");
1535                                         }
1536                                 }
1537
1538                                 bodyBuffer = null;
1539                                 if ((int) code >= 400) {
1540                                         string err = String.Format ("The remote server returned an error: ({0}) {1}.",
1541                                                                     (int) code, webResponse.StatusDescription);
1542                                         throwMe = new WebException (err, null, protoError, webResponse);
1543                                         webResponse.ReadAll ();
1544                                 } else if ((int) code == 304 && allowAutoRedirect) {
1545                                         string err = String.Format ("The remote server returned an error: ({0}) {1}.",
1546                                                                     (int) code, webResponse.StatusDescription);
1547                                         throwMe = new WebException (err, null, protoError, webResponse);
1548                                 } else if ((int) code >= 300 && allowAutoRedirect && redirects >= maxAutoRedirect) {
1549                                         throwMe = new WebException ("Max. redirections exceeded.", null,
1550                                                                     protoError, webResponse);
1551                                         webResponse.ReadAll ();
1552                                 }
1553                         }
1554
1555                         bodyBuffer = null;
1556                         if (throwMe == null) {
1557                                 bool b = false;
1558                                 int c = (int) code;
1559                                 if (allowAutoRedirect && c >= 300) {
1560                                         if (InternalAllowBuffering && writeStream.WriteBufferLength > 0) {
1561                                                 bodyBuffer = writeStream.WriteBuffer;
1562                                                 bodyBufferLength = writeStream.WriteBufferLength;
1563                                         }
1564                                         b = Redirect (result, code);
1565                                         if (b && ntlm_auth_state != 0)
1566                                                 ntlm_auth_state = 0;
1567                                 }
1568
1569                                 if (resp != null && c >= 300 && c != 304)
1570                                         resp.ReadAll ();
1571
1572                                 return b;
1573                         }
1574
1575                         if (!ThrowOnError)
1576                                 return false;
1577
1578                         if (writeStream != null) {
1579                                 writeStream.InternalClose ();
1580                                 writeStream = null;
1581                         }
1582
1583                         webResponse = null;
1584
1585                         throw throwMe;
1586                 }
1587         }
1588 }
1589