mcs/class/Mono.Security/Mono.Security.Protocol.Tls/SslStreamBase.cs

   1 // Transport Security Layer (TLS)
   2 // Copyright (c) 2003-2004 Carlos Guzman Alvarez
   3 // Copyright (C) 2006-2007 Novell, Inc (http://www.novell.com)
   4 //
   5 // Permission is hereby granted, free of charge, to any person obtaining
   6 // a copy of this software and associated documentation files (the
   7 // "Software"), to deal in the Software without restriction, including
   8 // without limitation the rights to use, copy, modify, merge, publish,
   9 // distribute, sublicense, and/or sell copies of the Software, and to
  10 // permit persons to whom the Software is furnished to do so, subject to
  11 // the following conditions:
  12 //
  13 // The above copyright notice and this permission notice shall be
  14 // included in all copies or substantial portions of the Software.
  15 //
  16 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  17 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  18 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  19 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  20 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  21 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  22 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23 //
  24
  25 using System;
  26 using System.Collections;
  27 using System.IO;
  28 using System.Net;
  29 using System.Net.Sockets;
  30 using System.Security.Cryptography;
  31 using System.Security.Cryptography.X509Certificates;
  32 using System.Threading;
  33
  34 namespace Mono.Security.Protocol.Tls
  35 {
  36         public abstract class SslStreamBase: Stream, IDisposable
  37         {
  38                 private delegate void AsyncHandshakeDelegate(InternalAsyncResult asyncResult, bool fromWrite);
  39
  40                 #region Fields
  41
  42                 static ManualResetEvent record_processing = new ManualResetEvent (true);
  43
  44                 internal Stream innerStream;
  45                 internal MemoryStream inputBuffer;
  46                 internal Context context;
  47                 internal RecordProtocol protocol;
  48                 internal bool ownsStream;
  49                 private volatile bool disposed;
  50                 private bool checkCertRevocationStatus;
  51                 private object negotiate;
  52                 private object read;
  53                 private object write;
  54                 private ManualResetEvent negotiationComplete;
  55
  56                 #endregion
  57
  58
  59                 #region Constructors
  60
  61                 protected SslStreamBase(
  62                         Stream stream,
  63                         bool ownsStream)
  64                 {
  65                         if (stream == null)
  66                         {
  67                                 throw new ArgumentNullException("stream is null.");
  68                         }
  69                         if (!stream.CanRead || !stream.CanWrite)
  70                         {
  71                                 throw new ArgumentNullException("stream is not both readable and writable.");
  72                         }
  73
  74                         this.inputBuffer = new MemoryStream();
  75                         this.innerStream = stream;
  76                         this.ownsStream = ownsStream;
  77                         this.negotiate = new object();
  78                         this.read = new object();
  79                         this.write = new object();
  80                         this.negotiationComplete = new ManualResetEvent(false);
  81                 }
  82
  83                 #endregion
  84
  85                 #region Handshakes
  86                 private void AsyncHandshakeCallback(IAsyncResult asyncResult)
  87                 {
  88                         InternalAsyncResult internalResult = asyncResult.AsyncState as InternalAsyncResult;
  89
  90                         try
  91                         {
  92                                 try
  93                                 {
  94                                         this.OnNegotiateHandshakeCallback(asyncResult);
  95                                 }
  96                                 catch (TlsException ex)
  97                                 {
  98                                         this.protocol.SendAlert(ex.Alert);
  99
 100                                         throw new IOException("The authentication or decryption has failed.", ex);
 101                                 }
 102                                 catch (Exception ex)
 103                                 {
 104                                         this.protocol.SendAlert(AlertDescription.InternalError);
 105
 106                                         throw new IOException("The authentication or decryption has failed.", ex);
 107                                 }
 108
 109                                 if (internalResult.ProceedAfterHandshake)
 110                                 {
 111                                         //kick off the read or write process (whichever called us) after the handshake is complete
 112                                         if (internalResult.FromWrite)
 113                                         {
 114                                                 InternalBeginWrite(internalResult);
 115                                         }
 116                                         else
 117                                         {
 118                                                 InternalBeginRead(internalResult);
 119                                         }
 120                                         negotiationComplete.Set();
 121                                 }
 122                                 else
 123                                 {
 124                                         negotiationComplete.Set();
 125                                         internalResult.SetComplete();
 126                                 }
 127
 128                         }
 129                         catch (Exception ex)
 130                         {
 131                                 negotiationComplete.Set();
 132                                 internalResult.SetComplete(ex);
 133                         }
 134                 }
 135
 136                 internal bool MightNeedHandshake
 137                 {
 138                         get
 139                         {
 140                                 if (this.context.HandshakeState == HandshakeState.Finished)
 141                                 {
 142                                         return false;
 143                                 }
 144                                 else
 145                                 {
 146                                         lock (this.negotiate)
 147                                         {
 148                                                 return (this.context.HandshakeState != HandshakeState.Finished);
 149                                         }
 150                                 }
 151                         }
 152                 }
 153
 154                 internal void NegotiateHandshake()
 155                 {
 156                         if (this.MightNeedHandshake)
 157                         {
 158                                 InternalAsyncResult ar = new InternalAsyncResult(null, null, null, 0, 0, false, false);
 159
 160                                 //if something already started negotiation, wait for it.
 161                                 //otherwise end it ourselves.
 162                                 if (!BeginNegotiateHandshake(ar))
 163                                 {
 164                                         this.negotiationComplete.WaitOne();
 165                                 }
 166                                 else
 167                                 {
 168                                         this.EndNegotiateHandshake(ar);
 169                                 }
 170                         }
 171                 }
 172
 173                 #endregion
 174
 175                 #region Abstracts/Virtuals
 176
 177                 internal abstract IAsyncResult OnBeginNegotiateHandshake(AsyncCallback callback, object state);
 178                 internal abstract void OnNegotiateHandshakeCallback(IAsyncResult asyncResult);
 179
 180                 internal abstract X509Certificate OnLocalCertificateSelection(X509CertificateCollection clientCertificates,
 181                                                                                                                         X509Certificate serverCertificate,
 182                                                                                                                         string targetHost,
 183                                                                                                                         X509CertificateCollection serverRequestedCertificates);
 184
 185                 internal abstract bool OnRemoteCertificateValidation(X509Certificate certificate, int[] errors);
 186                 internal abstract ValidationResult OnRemoteCertificateValidation2 (Mono.Security.X509.X509CertificateCollection collection);
 187                 internal abstract bool HaveRemoteValidation2Callback { get; }
 188
 189                 internal abstract AsymmetricAlgorithm OnLocalPrivateKeySelection(X509Certificate certificate, string targetHost);
 190
 191                 #endregion
 192
 193                 #region Event Methods
 194
 195                 internal X509Certificate RaiseLocalCertificateSelection(X509CertificateCollection certificates,
 196                                                                                                                         X509Certificate remoteCertificate,
 197                                                                                                                         string targetHost,
 198                                                                                                                         X509CertificateCollection requestedCertificates)
 199                 {
 200                         return OnLocalCertificateSelection(certificates, remoteCertificate, targetHost, requestedCertificates);
 201                 }
 202
 203                 internal bool RaiseRemoteCertificateValidation(X509Certificate certificate, int[] errors)
 204                 {
 205                         return OnRemoteCertificateValidation(certificate, errors);
 206                 }
 207
 208                 internal ValidationResult RaiseRemoteCertificateValidation2 (Mono.Security.X509.X509CertificateCollection collection)
 209                 {
 210                         return OnRemoteCertificateValidation2 (collection);
 211                 }
 212
 213                 internal AsymmetricAlgorithm RaiseLocalPrivateKeySelection(
 214                         X509Certificate certificate,
 215                         string targetHost)
 216                 {
 217                         return OnLocalPrivateKeySelection(certificate, targetHost);
 218                 }
 219                 #endregion
 220
 221                 #region Security Properties
 222
 223                 public bool CheckCertRevocationStatus
 224                 {
 225                         get { return this.checkCertRevocationStatus; }
 226                         set { this.checkCertRevocationStatus = value; }
 227                 }
 228
 229                 public CipherAlgorithmType CipherAlgorithm
 230                 {
 231                         get
 232                         {
 233                                 if (this.context.HandshakeState == HandshakeState.Finished)
 234                                 {
 235                                         return this.context.Current.Cipher.CipherAlgorithmType;
 236                                 }
 237
 238                                 return CipherAlgorithmType.None;
 239                         }
 240                 }
 241
 242                 public int CipherStrength
 243                 {
 244                         get
 245                         {
 246                                 if (this.context.HandshakeState == HandshakeState.Finished)
 247                                 {
 248                                         return this.context.Current.Cipher.EffectiveKeyBits;
 249                                 }
 250
 251                                 return 0;
 252                         }
 253                 }
 254
 255                 public HashAlgorithmType HashAlgorithm
 256                 {
 257                         get
 258                         {
 259                                 if (this.context.HandshakeState == HandshakeState.Finished)
 260                                 {
 261                                         return this.context.Current.Cipher.HashAlgorithmType;
 262                                 }
 263
 264                                 return HashAlgorithmType.None;
 265                         }
 266                 }
 267
 268                 public int HashStrength
 269                 {
 270                         get
 271                         {
 272                                 if (this.context.HandshakeState == HandshakeState.Finished)
 273                                 {
 274                                         return this.context.Current.Cipher.HashSize * 8;
 275                                 }
 276
 277                                 return 0;
 278                         }
 279                 }
 280
 281                 public int KeyExchangeStrength
 282                 {
 283                         get
 284                         {
 285                                 if (this.context.HandshakeState == HandshakeState.Finished)
 286                                 {
 287                                         return this.context.ServerSettings.Certificates[0].RSA.KeySize;
 288                                 }
 289
 290                                 return 0;
 291                         }
 292                 }
 293
 294                 public ExchangeAlgorithmType KeyExchangeAlgorithm
 295                 {
 296                         get
 297                         {
 298                                 if (this.context.HandshakeState == HandshakeState.Finished)
 299                                 {
 300                                         return this.context.Current.Cipher.ExchangeAlgorithmType;
 301                                 }
 302
 303                                 return ExchangeAlgorithmType.None;
 304                         }
 305                 }
 306
 307                 public SecurityProtocolType SecurityProtocol
 308                 {
 309                         get
 310                         {
 311                                 if (this.context.HandshakeState == HandshakeState.Finished)
 312                                 {
 313                                         return this.context.SecurityProtocol;
 314                                 }
 315
 316                                 return 0;
 317                         }
 318                 }
 319
 320                 public X509Certificate ServerCertificate
 321                 {
 322                         get
 323                         {
 324                                 if (this.context.HandshakeState == HandshakeState.Finished)
 325                                 {
 326                                         if (this.context.ServerSettings.Certificates != null &&
 327                                                 this.context.ServerSettings.Certificates.Count > 0)
 328                                         {
 329                                                 return new X509Certificate(this.context.ServerSettings.Certificates[0].RawData);
 330                                         }
 331                                 }
 332
 333                                 return null;
 334                         }
 335                 }
 336
 337                 // this is used by Mono's certmgr tool to download certificates
 338                 internal Mono.Security.X509.X509CertificateCollection ServerCertificates
 339                 {
 340                         get { return context.ServerSettings.Certificates; }
 341                 }
 342
 343                 #endregion
 344
 345                 #region Internal Async Result/State Class
 346
 347                 private class InternalAsyncResult : IAsyncResult
 348                 {
 349                         private object locker = new object ();
 350                         private AsyncCallback _userCallback;
 351                         private object _userState;
 352                         private Exception _asyncException;
 353                         private ManualResetEvent handle;
 354                         private bool completed;
 355                         private int _bytesRead;
 356                         private bool _fromWrite;
 357                         private bool _proceedAfterHandshake;
 358
 359                         private byte[] _buffer;
 360                         private int _offset;
 361                         private int _count;
 362
 363                         public InternalAsyncResult(AsyncCallback userCallback, object userState, byte[] buffer, int offset, int count, bool fromWrite, bool proceedAfterHandshake)
 364                         {
 365                                 _userCallback = userCallback;
 366                                 _userState = userState;
 367                                 _buffer = buffer;
 368                                 _offset = offset;
 369                                 _count = count;
 370                                 _fromWrite = fromWrite;
 371                                 _proceedAfterHandshake = proceedAfterHandshake;
 372                         }
 373
 374                         public bool ProceedAfterHandshake
 375                         {
 376                                 get { return _proceedAfterHandshake; }
 377                         }
 378
 379                         public bool FromWrite
 380                         {
 381                                 get { return _fromWrite; }
 382                         }
 383
 384                         public byte[] Buffer
 385                         {
 386                                 get { return _buffer; }
 387                         }
 388
 389                         public int Offset
 390                         {
 391                                 get { return _offset; }
 392                         }
 393
 394                         public int Count
 395                         {
 396                                 get { return _count; }
 397                         }
 398
 399                         public int BytesRead
 400                         {
 401                                 get { return _bytesRead; }
 402                         }
 403
 404                         public object AsyncState
 405                         {
 406                                 get { return _userState; }
 407                         }
 408
 409                         public Exception AsyncException
 410                         {
 411                                 get { return _asyncException; }
 412                         }
 413
 414                         public bool CompletedWithError
 415                         {
 416                                 get {
 417                                         if (IsCompleted == false)
 418                                                 return false;
 419                                         return null != _asyncException;
 420                                 }
 421                         }
 422
 423                         public WaitHandle AsyncWaitHandle
 424                         {
 425                                 get {
 426                                         lock (locker) {
 427                                                 if (handle == null)
 428                                                         handle = new ManualResetEvent (completed);
 429                                         }
 430                                         return handle;
 431                                 }
 432                         }
 433
 434                         public bool CompletedSynchronously
 435                         {
 436                                 get { return false; }
 437                         }
 438
 439                         public bool IsCompleted
 440                         {
 441                                 get {
 442                                         lock (locker)
 443                                                 return completed;
 444                                 }
 445                         }
 446
 447                         private void SetComplete(Exception ex, int bytesRead)
 448                         {
 449                                 lock (locker) {
 450                                         if (completed)
 451                                                 return;
 452
 453                                         completed = true;
 454                                         _asyncException = ex;
 455                                         _bytesRead = bytesRead;
 456                                         if (handle != null)
 457                                                 handle.Set ();
 458                                 }
 459                                 if (_userCallback != null)
 460                                         _userCallback.BeginInvoke (this, null, null);
 461                         }
 462
 463                         public void SetComplete(Exception ex)
 464                         {
 465                                 SetComplete(ex, 0);
 466                         }
 467
 468                         public void SetComplete(int bytesRead)
 469                         {
 470                                 SetComplete(null, bytesRead);
 471                         }
 472
 473                         public void SetComplete()
 474                         {
 475                                 SetComplete(null, 0);
 476                         }
 477                 }
 478                 #endregion
 479
 480                 #region Stream Overrides and Async Stream Operations
 481
 482                 private bool BeginNegotiateHandshake(InternalAsyncResult asyncResult)
 483                 {
 484                         try
 485                         {
 486                                 lock (this.negotiate)
 487                                 {
 488                                         if (this.context.HandshakeState == HandshakeState.None)
 489                                         {
 490                                                 this.OnBeginNegotiateHandshake(new AsyncCallback(AsyncHandshakeCallback), asyncResult);
 491
 492                                                 return true;
 493                                         }
 494                                         else
 495                                         {
 496                                                 return false;
 497                                         }
 498                                 }
 499                         }
 500                         catch (TlsException ex)
 501                         {
 502                                 this.negotiationComplete.Set();
 503                                 this.protocol.SendAlert(ex.Alert);
 504
 505                                 throw new IOException("The authentication or decryption has failed.", ex);
 506                         }
 507                         catch (Exception ex)
 508                         {
 509                                 this.negotiationComplete.Set();
 510                                 this.protocol.SendAlert(AlertDescription.InternalError);
 511
 512                                 throw new IOException("The authentication or decryption has failed.", ex);
 513                         }
 514                 }
 515
 516                 private void EndNegotiateHandshake(InternalAsyncResult asyncResult)
 517                 {
 518                         if (asyncResult.IsCompleted == false)
 519                                 asyncResult.AsyncWaitHandle.WaitOne();
 520
 521                         if (asyncResult.CompletedWithError)
 522                         {
 523                                 throw asyncResult.AsyncException;
 524                         }
 525                 }
 526
 527                 public override IAsyncResult BeginRead(
 528                         byte[] buffer,
 529                         int offset,
 530                         int count,
 531                         AsyncCallback callback,
 532                         object state)
 533                 {
 534                         this.checkDisposed();
 535
 536                         if (buffer == null)
 537                         {
 538                                 throw new ArgumentNullException("buffer is a null reference.");
 539                         }
 540                         if (offset < 0)
 541                         {
 542                                 throw new ArgumentOutOfRangeException("offset is less than 0.");
 543                         }
 544                         if (offset > buffer.Length)
 545                         {
 546                                 throw new ArgumentOutOfRangeException("offset is greater than the length of buffer.");
 547                         }
 548                         if (count < 0)
 549                         {
 550                                 throw new ArgumentOutOfRangeException("count is less than 0.");
 551                         }
 552                         if (count > (buffer.Length - offset))
 553                         {
 554                                 throw new ArgumentOutOfRangeException("count is less than the length of buffer minus the value of the offset parameter.");
 555                         }
 556
 557                         InternalAsyncResult asyncResult = new InternalAsyncResult(callback, state, buffer, offset, count, false, true);
 558
 559                         if (this.MightNeedHandshake)
 560                         {
 561                                 if (! BeginNegotiateHandshake(asyncResult))
 562                                 {
 563                                         //we made it down here so the handshake was not started.
 564                                         //another thread must have started it in the mean time.
 565                                         //wait for it to complete and then perform our original operation
 566                                         this.negotiationComplete.WaitOne();
 567
 568                                         InternalBeginRead(asyncResult);
 569                                 }
 570                         }
 571                         else
 572                         {
 573                                 InternalBeginRead(asyncResult);
 574                         }
 575
 576                         return asyncResult;
 577                 }
 578
 579                 // bigger than max record length for SSL/TLS
 580                 private byte[] recbuf = new byte[16384];
 581
 582                 private void InternalBeginRead(InternalAsyncResult asyncResult)
 583                 {
 584                         try
 585                         {
 586                                 int preReadSize = 0;
 587
 588                                 lock (this.read)
 589                                 {
 590                                         // If actual buffer is fully read, reset it
 591                                         bool shouldReset = this.inputBuffer.Position == this.inputBuffer.Length && this.inputBuffer.Length > 0;
 592
 593                                         // If the buffer isn't fully read, but does have data, we need to immediately
 594                                         // read the info from the buffer and let the user know that they have more data.
 595                                         bool shouldReadImmediately = (this.inputBuffer.Length > 0) && (asyncResult.Count > 0);
 596
 597                                         if (shouldReset)
 598                                         {
 599                                                 this.resetBuffer();
 600                                         }
 601                                         else if (shouldReadImmediately)
 602                                         {
 603                                                 preReadSize = this.inputBuffer.Read(asyncResult.Buffer, asyncResult.Offset, asyncResult.Count);
 604                                         }
 605                                 }
 606
 607                                 // This is explicitly done outside the synclock to avoid
 608                                 // any potential deadlocks in the delegate call.
 609                                 if (0 < preReadSize)
 610                                 {
 611                                         asyncResult.SetComplete(preReadSize);
 612                                 }
 613                                 else if (!this.context.ReceivedConnectionEnd)
 614                                 {
 615                                         // this will read data from the network until we have (at least) one
 616                                         // record to send back to the caller
 617                                         this.innerStream.BeginRead(recbuf, 0, recbuf.Length,
 618                                                 new AsyncCallback(InternalReadCallback), new object[] { recbuf, asyncResult });
 619                                 }
 620                                 else
 621                                 {
 622                                         // We're done with the connection so we need to let the caller know with 0 bytes read
 623                                         asyncResult.SetComplete(0);
 624                                 }
 625                         }
 626                         catch (TlsException ex)
 627                         {
 628                                 this.protocol.SendAlert(ex.Alert);
 629
 630                                 throw new IOException("The authentication or decryption has failed.", ex);
 631                         }
 632                         catch (Exception ex)
 633                         {
 634                                 throw new IOException("IO exception during read.", ex);
 635                         }
 636                 }
 637
 638
 639                 private MemoryStream recordStream = new MemoryStream();
 640
 641                 // read encrypted data until we have enough to decrypt (at least) one
 642                 // record and return are the records (may be more than one) we have
 643                 private void InternalReadCallback(IAsyncResult result)
 644                 {
 645                         if (this.disposed)
 646                                 return;
 647
 648                         object[] state = (object[])result.AsyncState;
 649                         byte[] recbuf = (byte[])state[0];
 650                         InternalAsyncResult internalResult = (InternalAsyncResult)state[1];
 651
 652                         try
 653                         {
 654                                 int n = innerStream.EndRead(result);
 655                                 if (n > 0)
 656                                 {
 657                                         // Add the just received data to the waiting data
 658                                         recordStream.Write(recbuf, 0, n);
 659                                 }
 660                                 else
 661                                 {
 662                                         // 0 length data means this read operation is done (lost connection in the case of a network stream).
 663                                         internalResult.SetComplete(0);
 664                                         return;
 665                                 }
 666
 667                                 bool dataToReturn = false;
 668                                 long pos = recordStream.Position;
 669
 670                                 recordStream.Position = 0;
 671                                 byte[] record = null;
 672
 673                                 // don't try to decode record unless we have at least 5 bytes
 674                                 // i.e. type (1), protocol (2) and length (2)
 675                                 if (recordStream.Length >= 5)
 676                                 {
 677                                         record = this.protocol.ReceiveRecord(recordStream);
 678                                 }
 679
 680                                 // a record of 0 length is valid (and there may be more record after it)
 681                                 while (record != null)
 682                                 {
 683                                         // we probably received more stuff after the record, and we must keep it!
 684                                         long remainder = recordStream.Length - recordStream.Position;
 685                                         byte[] outofrecord = null;
 686                                         if (remainder > 0)
 687                                         {
 688                                                 outofrecord = new byte[remainder];
 689                                                 recordStream.Read(outofrecord, 0, outofrecord.Length);
 690                                         }
 691
 692                                         lock (this.read)
 693                                         {
 694                                                 long position = this.inputBuffer.Position;
 695
 696                                                 if (record.Length > 0)
 697                                                 {
 698                                                         // Write new data to the inputBuffer
 699                                                         this.inputBuffer.Seek(0, SeekOrigin.End);
 700                                                         this.inputBuffer.Write(record, 0, record.Length);
 701
 702                                                         // Restore buffer position
 703                                                         this.inputBuffer.Seek(position, SeekOrigin.Begin);
 704                                                         dataToReturn = true;
 705                                                 }
 706                                         }
 707
 708                                         recordStream.SetLength(0);
 709                                         record = null;
 710
 711                                         if (remainder > 0)
 712                                         {
 713                                                 recordStream.Write(outofrecord, 0, outofrecord.Length);
 714                                                 // type (1), protocol (2) and length (2)
 715                                                 if (recordStream.Length >= 5)
 716                                                 {
 717                                                         // try to see if another record is available
 718                                                         recordStream.Position = 0;
 719                                                         record = this.protocol.ReceiveRecord(recordStream);
 720                                                         if (record == null)
 721                                                                 pos = recordStream.Length;
 722                                                 }
 723                                                 else
 724                                                         pos = remainder;
 725                                         }
 726                                         else
 727                                                 pos = 0;
 728                                 }
 729
 730                                 if (!dataToReturn && (n > 0))
 731                                 {
 732                                         if (context.ReceivedConnectionEnd) {
 733                                                 internalResult.SetComplete (0);
 734                                         } else {
 735                                                 // there is no record to return to caller and (possibly) more data waiting
 736                                                 // so continue reading from network (and appending to stream)
 737                                                 recordStream.Position = recordStream.Length;
 738                                                 this.innerStream.BeginRead(recbuf, 0, recbuf.Length,
 739                                                         new AsyncCallback(InternalReadCallback), state);
 740                                         }
 741                                 }
 742                                 else
 743                                 {
 744                                         // we have record(s) to return -or- no more available to read from network
 745                                         // reset position for further reading
 746                                         recordStream.Position = pos;
 747
 748                                         int bytesRead = 0;
 749                                         lock (this.read)
 750                                         {
 751                                                 bytesRead = this.inputBuffer.Read(internalResult.Buffer, internalResult.Offset, internalResult.Count);
 752                                         }
 753
 754                                         internalResult.SetComplete(bytesRead);
 755                                 }
 756                         }
 757                         catch (Exception ex)
 758                         {
 759                                 internalResult.SetComplete(ex);
 760                         }
 761
 762                 }
 763
 764                 private void InternalBeginWrite(InternalAsyncResult asyncResult)
 765                 {
 766                         try
 767                         {
 768                                 // Send the buffer as a TLS record
 769
 770                                 lock (this.write)
 771                                 {
 772                                         byte[] record = this.protocol.EncodeRecord(
 773                                                 ContentType.ApplicationData, asyncResult.Buffer, asyncResult.Offset, asyncResult.Count);
 774
 775                                         this.innerStream.BeginWrite(
 776                                                 record, 0, record.Length, new AsyncCallback(InternalWriteCallback), asyncResult);
 777                                 }
 778                         }
 779                         catch (TlsException ex)
 780                         {
 781                                 this.protocol.SendAlert(ex.Alert);
 782                                 this.Close();
 783
 784                                 throw new IOException("The authentication or decryption has failed.", ex);
 785                         }
 786                         catch (Exception ex)
 787                         {
 788                                 throw new IOException("IO exception during Write.", ex);
 789                         }
 790                 }
 791
 792                 private void InternalWriteCallback(IAsyncResult ar)
 793                 {
 794                         if (this.disposed)
 795                                 return;
 796
 797                         InternalAsyncResult internalResult = (InternalAsyncResult)ar.AsyncState;
 798
 799                         try
 800                         {
 801                                 this.innerStream.EndWrite(ar);
 802                                 internalResult.SetComplete();
 803                         }
 804                         catch (Exception ex)
 805                         {
 806                                 internalResult.SetComplete(ex);
 807                         }
 808                 }
 809
 810                 public override IAsyncResult BeginWrite(
 811                         byte[] buffer,
 812                         int offset,
 813                         int count,
 814                         AsyncCallback callback,
 815                         object state)
 816                 {
 817                         this.checkDisposed();
 818
 819                         if (buffer == null)
 820                         {
 821                                 throw new ArgumentNullException("buffer is a null reference.");
 822                         }
 823                         if (offset < 0)
 824                         {
 825                                 throw new ArgumentOutOfRangeException("offset is less than 0.");
 826                         }
 827                         if (offset > buffer.Length)
 828                         {
 829                                 throw new ArgumentOutOfRangeException("offset is greater than the length of buffer.");
 830                         }
 831                         if (count < 0)
 832                         {
 833                                 throw new ArgumentOutOfRangeException("count is less than 0.");
 834                         }
 835                         if (count > (buffer.Length - offset))
 836                         {
 837                                 throw new ArgumentOutOfRangeException("count is less than the length of buffer minus the value of the offset parameter.");
 838                         }
 839
 840
 841                         InternalAsyncResult asyncResult = new InternalAsyncResult(callback, state, buffer, offset, count, true, true);
 842
 843                         if (this.MightNeedHandshake)
 844                         {
 845                                 if (! BeginNegotiateHandshake(asyncResult))
 846                                 {
 847                                         //we made it down here so the handshake was not started.
 848                                         //another thread must have started it in the mean time.
 849                                         //wait for it to complete and then perform our original operation
 850                                         this.negotiationComplete.WaitOne();
 851
 852                                         InternalBeginWrite(asyncResult);
 853                                 }
 854                         }
 855                         else
 856                         {
 857                                 InternalBeginWrite(asyncResult);
 858                         }
 859
 860                         return asyncResult;
 861                 }
 862
 863                 public override int EndRead(IAsyncResult asyncResult)
 864                 {
 865                         this.checkDisposed();
 866
 867                         InternalAsyncResult internalResult = asyncResult as InternalAsyncResult;
 868                         if (internalResult == null)
 869                         {
 870                                 throw new ArgumentNullException("asyncResult is null or was not obtained by calling BeginRead.");
 871                         }
 872
 873                         // Always wait until the read is complete
 874                         if (!asyncResult.IsCompleted)
 875                         {
 876                                 if (!asyncResult.AsyncWaitHandle.WaitOne ())
 877                                         throw new TlsException (AlertDescription.InternalError, "Couldn't complete EndRead");
 878                         }
 879
 880                         if (internalResult.CompletedWithError)
 881                         {
 882                                 throw internalResult.AsyncException;
 883                         }
 884
 885                         return internalResult.BytesRead;
 886                 }
 887
 888                 public override void EndWrite(IAsyncResult asyncResult)
 889                 {
 890                         this.checkDisposed();
 891
 892                         InternalAsyncResult internalResult = asyncResult as InternalAsyncResult;
 893                         if (internalResult == null)
 894                         {
 895                                 throw new ArgumentNullException("asyncResult is null or was not obtained by calling BeginWrite.");
 896                         }
 897
 898
 899                         if (!asyncResult.IsCompleted)
 900                         {
 901                                 if (!internalResult.AsyncWaitHandle.WaitOne ())
 902                                         throw new TlsException (AlertDescription.InternalError, "Couldn't complete EndWrite");
 903                         }
 904
 905                         if (internalResult.CompletedWithError)
 906                         {
 907                                 throw internalResult.AsyncException;
 908                         }
 909                 }
 910
 911                 public override void Close()
 912                 {
 913                         base.Close ();
 914                 }
 915
 916                 public override void Flush()
 917                 {
 918                         this.checkDisposed();
 919
 920                         this.innerStream.Flush();
 921                 }
 922
 923                 public int Read(byte[] buffer)
 924                 {
 925                         return this.Read(buffer, 0, buffer.Length);
 926                 }
 927
 928                 public override int Read(byte[] buffer, int offset, int count)
 929                 {
 930                         this.checkDisposed ();
 931
 932                         if (buffer == null)
 933                         {
 934                                 throw new ArgumentNullException ("buffer");
 935                         }
 936                         if (offset < 0)
 937                         {
 938                                 throw new ArgumentOutOfRangeException("offset is less than 0.");
 939                         }
 940                         if (offset > buffer.Length)
 941                         {
 942                                 throw new ArgumentOutOfRangeException("offset is greater than the length of buffer.");
 943                         }
 944                         if (count < 0)
 945                         {
 946                                 throw new ArgumentOutOfRangeException("count is less than 0.");
 947                         }
 948                         if (count > (buffer.Length - offset))
 949                         {
 950                                 throw new ArgumentOutOfRangeException("count is less than the length of buffer minus the value of the offset parameter.");
 951                         }
 952
 953                         if (this.context.HandshakeState != HandshakeState.Finished)
 954                         {
 955                                 this.NegotiateHandshake (); // Handshake negotiation
 956                         }
 957
 958                         lock (this.read) {
 959                                 try {
 960                                         record_processing.Reset ();
 961                                         // do we already have some decrypted data ?
 962                                         if (this.inputBuffer.Position > 0) {
 963                                                 // or maybe we used all the buffer before ?
 964                                                 if (this.inputBuffer.Position == this.inputBuffer.Length) {
 965                                                         this.inputBuffer.SetLength (0);
 966                                                 } else {
 967                                                         int n = this.inputBuffer.Read (buffer, offset, count);
 968                                                         if (n > 0) {
 969                                                                 record_processing.Set ();
 970                                                                 return n;
 971                                                         }
 972                                                 }
 973                                         }
 974
 975                                         bool needMoreData = false;
 976                                         while (true) {
 977                                                 // we first try to process the read with the data we already have
 978                                                 if ((recordStream.Position == 0) || needMoreData) {
 979                                                         needMoreData = false;
 980                                                         // if we loop, then it either means we need more data
 981                                                         byte[] recbuf = new byte[16384];
 982                                                         int n = 0;
 983                                                         if (count == 1) {
 984                                                                 int value = innerStream.ReadByte ();
 985                                                                 if (value >= 0) {
 986                                                                         recbuf[0] = (byte) value;
 987                                                                         n = 1;
 988                                                                 }
 989                                                         } else {
 990                                                                 n = innerStream.Read (recbuf, 0, recbuf.Length);
 991                                                         }
 992                                                         if (n > 0) {
 993                                                                 // Add the new received data to the waiting data
 994                                                                 if ((recordStream.Length > 0) && (recordStream.Position != recordStream.Length))
 995                                                                         recordStream.Seek (0, SeekOrigin.End);
 996                                                                 recordStream.Write (recbuf, 0, n);
 997                                                         } else {
 998                                                                 // or that the read operation is done (lost connection in the case of a network stream).
 999                                                                 record_processing.Set ();
1000                                                                 return 0;
1001                                                         }
1002                                                 }
1003
1004                                                 bool dataToReturn = false;
1005
1006                                                 recordStream.Position = 0;
1007                                                 byte[] record = null;
1008
1009                                                 // don't try to decode record unless we have at least 5 bytes
1010                                                 // i.e. type (1), protocol (2) and length (2)
1011                                                 if (recordStream.Length >= 5) {
1012                                                         record = this.protocol.ReceiveRecord (recordStream);
1013                                                         needMoreData = (record == null);
1014                                                 }
1015
1016                                                 // a record of 0 length is valid (and there may be more record after it)
1017                                                 while (record != null) {
1018                                                         // we probably received more stuff after the record, and we must keep it!
1019                                                         long remainder = recordStream.Length - recordStream.Position;
1020                                                         byte[] outofrecord = null;
1021                                                         if (remainder > 0) {
1022                                                                 outofrecord = new byte[remainder];
1023                                                                 recordStream.Read (outofrecord, 0, outofrecord.Length);
1024                                                         }
1025
1026                                                         long position = this.inputBuffer.Position;
1027
1028                                                         if (record.Length > 0) {
1029                                                                 // Write new data to the inputBuffer
1030                                                                 this.inputBuffer.Seek (0, SeekOrigin.End);
1031                                                                 this.inputBuffer.Write (record, 0, record.Length);
1032
1033                                                                 // Restore buffer position
1034                                                                 this.inputBuffer.Seek (position, SeekOrigin.Begin);
1035                                                                 dataToReturn = true;
1036                                                         }
1037
1038                                                         recordStream.SetLength (0);
1039                                                         record = null;
1040
1041                                                         if (remainder > 0) {
1042                                                                 recordStream.Write (outofrecord, 0, outofrecord.Length);
1043                                                         }
1044
1045                                                         if (dataToReturn) {
1046                                                                 // we have record(s) to return -or- no more available to read from network
1047                                                                 // reset position for further reading
1048                                                                 int i = inputBuffer.Read (buffer, offset, count);
1049                                                                 record_processing.Set ();
1050                                                                 return i;
1051                                                         }
1052                                                 }
1053                                         }
1054                                 }
1055                                 catch (TlsException ex)
1056                                 {
1057                                         throw new IOException("The authentication or decryption has failed.", ex);
1058                                 }
1059                                 catch (Exception ex)
1060                                 {
1061                                         throw new IOException("IO exception during read.", ex);
1062                                 }
1063                         }
1064                 }
1065
1066                 public override long Seek(long offset, SeekOrigin origin)
1067                 {
1068                         throw new NotSupportedException();
1069                 }
1070
1071                 public override void SetLength(long value)
1072                 {
1073                         throw new NotSupportedException();
1074                 }
1075
1076                 public void Write(byte[] buffer)
1077                 {
1078                         this.Write(buffer, 0, buffer.Length);
1079                 }
1080
1081                 public override void Write(byte[] buffer, int offset, int count)
1082                 {
1083                         this.checkDisposed ();
1084
1085                         if (buffer == null)
1086                         {
1087                                 throw new ArgumentNullException ("buffer");
1088                         }
1089                         if (offset < 0)
1090                         {
1091                                 throw new ArgumentOutOfRangeException("offset is less than 0.");
1092                         }
1093                         if (offset > buffer.Length)
1094                         {
1095                                 throw new ArgumentOutOfRangeException("offset is greater than the length of buffer.");
1096                         }
1097                         if (count < 0)
1098                         {
1099                                 throw new ArgumentOutOfRangeException("count is less than 0.");
1100                         }
1101                         if (count > (buffer.Length - offset))
1102                         {
1103                                 throw new ArgumentOutOfRangeException("count is less than the length of buffer minus the value of the offset parameter.");
1104                         }
1105
1106                         if (this.context.HandshakeState != HandshakeState.Finished)
1107                         {
1108                                 this.NegotiateHandshake ();
1109                         }
1110
1111                         lock (this.write)
1112                         {
1113                                 try
1114                                 {
1115                                         // Send the buffer as a TLS record
1116                                         byte[] record = this.protocol.EncodeRecord (ContentType.ApplicationData, buffer, offset, count);
1117                                         this.innerStream.Write (record, 0, record.Length);
1118                                 }
1119                                 catch (TlsException ex)
1120                                 {
1121                                         this.protocol.SendAlert(ex.Alert);
1122                                         this.Close();
1123                                         throw new IOException("The authentication or decryption has failed.", ex);
1124                                 }
1125                                 catch (Exception ex)
1126                                 {
1127                                         throw new IOException("IO exception during Write.", ex);
1128                                 }
1129                         }
1130                 }
1131
1132                 public override bool CanRead
1133                 {
1134                         get { return this.innerStream.CanRead; }
1135                 }
1136
1137                 public override bool CanSeek
1138                 {
1139                         get { return false; }
1140                 }
1141
1142                 public override bool CanWrite
1143                 {
1144                         get { return this.innerStream.CanWrite; }
1145                 }
1146
1147                 public override long Length
1148                 {
1149                         get { throw new NotSupportedException(); }
1150                 }
1151
1152                 public override long Position
1153                 {
1154                         get
1155                         {
1156                                 throw new NotSupportedException();
1157                         }
1158                         set
1159                         {
1160                                 throw new NotSupportedException();
1161                         }
1162                 }
1163                 #endregion
1164
1165                 #region IDisposable Members and Finalizer
1166
1167                 ~SslStreamBase()
1168                 {
1169                         this.Dispose(false);
1170                 }
1171
1172                 protected override void Dispose (bool disposing)
1173                 {
1174                         if (!this.disposed)
1175                         {
1176                                 if (disposing)
1177                                 {
1178                                         if (this.innerStream != null)
1179                                         {
1180                                                 if (this.context.HandshakeState == HandshakeState.Finished &&
1181                                                         !this.context.SentConnectionEnd)
1182                                                 {
1183                                                         // Write close notify
1184                                                         try {
1185                                                                 this.protocol.SendAlert(AlertDescription.CloseNotify);
1186                                                         } catch {
1187                                                         }
1188                                                 }
1189
1190                                                 if (this.ownsStream)
1191                                                 {
1192                                                         // Close inner stream
1193                                                         this.innerStream.Close();
1194                                                 }
1195                                         }
1196                                         this.ownsStream = false;
1197                                         this.innerStream = null;
1198                                 }
1199
1200                                 this.disposed = true;
1201                                 base.Dispose (disposing);
1202                         }
1203                 }
1204
1205                 #endregion
1206
1207                 #region Misc Methods
1208
1209                 private void resetBuffer()
1210                 {
1211                         this.inputBuffer.SetLength(0);
1212                         this.inputBuffer.Position = 0;
1213                 }
1214
1215                 internal void checkDisposed()
1216                 {
1217                         if (this.disposed)
1218                         {
1219                                 throw new ObjectDisposedException("The Stream is closed.");
1220                         }
1221                 }
1222
1223                 #endregion
1224
1225         }
1226 }