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

   1 // Transport Security Layer (TLS)
   2 // Copyright (c) 2003-2004 Carlos Guzman Alvarez
   3
   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 using Mono.Security.Protocol.Tls.Handshake;
  35
  36 namespace Mono.Security.Protocol.Tls
  37 {
  38         #region Delegates
  39
  40         public delegate bool CertificateValidationCallback(
  41                 X509Certificate certificate,
  42                 int[]                   certificateErrors);
  43
  44         public delegate X509Certificate CertificateSelectionCallback(
  45                 X509CertificateCollection       clientCertificates,
  46                 X509Certificate                         serverCertificate,
  47                 string                                          targetHost,
  48                 X509CertificateCollection       serverRequestedCertificates);
  49
  50         public delegate AsymmetricAlgorithm PrivateKeySelectionCallback(
  51                 X509Certificate certificate,
  52                 string                  targetHost);
  53
  54         #endregion
  55
  56         public class SslClientStream : SslStreamBase
  57         {
  58                 #region Internal Events
  59
  60                 internal event CertificateValidationCallback    ServerCertValidation;
  61                 internal event CertificateSelectionCallback             ClientCertSelection;
  62                 internal event PrivateKeySelectionCallback              PrivateKeySelection;
  63
  64                 #endregion
  65
  66                 #region Properties
  67
  68                 // required by HttpsClientStream for proxy support
  69                 internal Stream InputBuffer
  70                 {
  71                         get { return base.inputBuffer; }
  72                 }
  73
  74                 public X509CertificateCollection ClientCertificates
  75                 {
  76                         get { return this.context.ClientSettings.Certificates; }
  77                 }
  78
  79                 public X509Certificate SelectedClientCertificate
  80                 {
  81                         get { return this.context.ClientSettings.ClientCertificate; }
  82                 }
  83
  84                 #endregion
  85
  86                 #region Callback Properties
  87
  88                 public CertificateValidationCallback ServerCertValidationDelegate
  89                 {
  90                         get { return this.ServerCertValidation; }
  91                         set { this.ServerCertValidation = value; }
  92                 }
  93
  94                 public CertificateSelectionCallback ClientCertSelectionDelegate
  95                 {
  96                         get { return this.ClientCertSelection; }
  97                         set { this.ClientCertSelection = value; }
  98                 }
  99
 100                 public PrivateKeySelectionCallback PrivateKeyCertSelectionDelegate
 101                 {
 102                         get { return this.PrivateKeySelection; }
 103                         set { this.PrivateKeySelection = value; }
 104                 }
 105
 106                 #endregion
 107
 108                 #region Constructors
 109
 110                 public SslClientStream(
 111                         Stream  stream,
 112                         string  targetHost,
 113                         bool    ownsStream)
 114                         : this(
 115                                 stream, targetHost, ownsStream,
 116                                 SecurityProtocolType.Default, null)
 117                 {
 118                 }
 119
 120                 public SslClientStream(
 121                         Stream                          stream,
 122                         string                          targetHost,
 123                         X509Certificate         clientCertificate)
 124                         : this(
 125                                 stream, targetHost, false, SecurityProtocolType.Default,
 126                                 new X509CertificateCollection(new X509Certificate[]{clientCertificate}))
 127                 {
 128                 }
 129
 130                 public SslClientStream(
 131                         Stream                                          stream,
 132                         string                                          targetHost,
 133                         X509CertificateCollection clientCertificates) :
 134                         this(
 135                                 stream, targetHost, false, SecurityProtocolType.Default,
 136                                 clientCertificates)
 137                 {
 138                 }
 139
 140                 public SslClientStream(
 141                         Stream                                  stream,
 142                         string                                  targetHost,
 143                         bool                                    ownsStream,
 144                         SecurityProtocolType    securityProtocolType)
 145                         : this(
 146                                 stream, targetHost, ownsStream, securityProtocolType,
 147                                 new X509CertificateCollection())
 148                 {
 149                 }
 150
 151                 public SslClientStream(
 152                         Stream                                          stream,
 153                         string                                          targetHost,
 154                         bool                                            ownsStream,
 155                         SecurityProtocolType            securityProtocolType,
 156                         X509CertificateCollection       clientCertificates):
 157                         base(stream, ownsStream)
 158                 {
 159                         if (targetHost == null || targetHost.Length == 0)
 160                         {
 161                                 throw new ArgumentNullException("targetHost is null or an empty string.");
 162                         }
 163
 164                         this.context = new ClientContext(
 165                                 this,
 166                                 securityProtocolType,
 167                                 targetHost,
 168                                 clientCertificates);
 169
 170                         this.protocol = new ClientRecordProtocol(innerStream, (ClientContext)this.context);
 171                 }
 172
 173                 #endregion
 174
 175                 #region Finalizer
 176
 177                 ~SslClientStream()
 178                 {
 179                         base.Dispose(false);
 180                 }
 181
 182                 #endregion
 183
 184                 #region IDisposable Methods
 185
 186                 protected override void Dispose(bool disposing)
 187                 {
 188                         base.Dispose(disposing);
 189
 190                         if (disposing)
 191                         {
 192                                 this.ServerCertValidation = null;
 193                                 this.ClientCertSelection = null;
 194                                 this.PrivateKeySelection = null;
 195                         }
 196                 }
 197
 198                 #endregion
 199
 200                 #region Handshake Methods
 201
 202                 /*
 203                         Client                                                                                  Server
 204
 205                         ClientHello                 -------->
 206                                                                                                                         ServerHello
 207                                                                                                                         Certificate*
 208                                                                                                                         ServerKeyExchange*
 209                                                                                                                         CertificateRequest*
 210                                                                                 <--------                       ServerHelloDone
 211                         Certificate*
 212                         ClientKeyExchange
 213                         CertificateVerify*
 214                         [ChangeCipherSpec]
 215                         Finished                    -------->
 216                                                                                                                         [ChangeCipherSpec]
 217                                                                                 <--------           Finished
 218                         Application Data            <------->                   Application Data
 219
 220                                         Fig. 1 - Message flow for a full handshake
 221                 */
 222
 223                 internal override IAsyncResult OnBeginNegotiateHandshake(AsyncCallback callback, object state)
 224                 {
 225                         try
 226                         {
 227                                 if (this.context.HandshakeState != HandshakeState.None)
 228                                 {
 229                                         this.context.Clear();
 230                                 }
 231
 232                                 // Obtain supported cipher suites
 233                                 this.context.SupportedCiphers = CipherSuiteFactory.GetSupportedCiphers(this.context.SecurityProtocol);
 234
 235                                 // Set handshake state
 236                                 this.context.HandshakeState = HandshakeState.Started;
 237
 238                                 // Send client hello
 239                                 return this.protocol.BeginSendRecord(HandshakeType.ClientHello, callback, state);
 240                         }
 241                         catch (TlsException ex)
 242                         {
 243                                 this.protocol.SendAlert(ex.Alert);
 244
 245                                 throw new IOException("The authentication or decryption has failed.", ex);
 246                         }
 247                         catch (Exception ex)
 248                         {
 249                                 this.protocol.SendAlert(AlertDescription.InternalError);
 250
 251                                 throw new IOException("The authentication or decryption has failed.", ex);
 252                         }
 253                 }
 254
 255                 private void SafeReceiveRecord (Stream s)
 256                 {
 257                         byte[] record = this.protocol.ReceiveRecord (s);
 258                         if ((record == null) || (record.Length == 0)) {
 259                                 throw new TlsException (
 260                                         AlertDescription.HandshakeFailiure,
 261                                         "The server stopped the handshake.");
 262                         }
 263                 }
 264
 265                 internal override void OnNegotiateHandshakeCallback(IAsyncResult asyncResult)
 266                 {
 267                         this.protocol.EndSendRecord(asyncResult);
 268
 269                         // Read server response
 270                         while (this.context.LastHandshakeMsg != HandshakeType.ServerHelloDone)
 271                         {
 272                                 // Read next record
 273                                 SafeReceiveRecord (this.innerStream);
 274
 275                                 // special case for abbreviated handshake where no ServerHelloDone is sent from the server
 276                                 if (this.context.AbbreviatedHandshake && (this.context.LastHandshakeMsg == HandshakeType.ServerHello))
 277                                         break;
 278                         }
 279
 280                         // the handshake is much easier if we can reuse a preivous session settings
 281                         if (this.context.AbbreviatedHandshake)
 282                         {
 283                                 ClientSessionCache.SetContextFromCache (this.context);
 284                                 this.context.Cipher.ComputeKeys ();
 285                                 this.context.Cipher.InitializeCipher ();
 286
 287                                 // Send Cipher Spec protocol
 288                                 this.protocol.SendChangeCipherSpec ();
 289
 290                                 // Read record until server finished is received
 291                                 while (this.context.HandshakeState != HandshakeState.Finished)
 292                                 {
 293                                         // If all goes well this will process messages:
 294                                         //              Change Cipher Spec
 295                                         //              Server finished
 296                                         SafeReceiveRecord (this.innerStream);
 297                                 }
 298
 299                                 // Send Finished message
 300                                 this.protocol.SendRecord (HandshakeType.Finished);
 301                         }
 302                         else
 303                         {
 304                                 // Send client certificate if requested
 305                                 // even if the server ask for it it _may_ still be optional
 306                                 bool clientCertificate = this.context.ServerSettings.CertificateRequest;
 307
 308                                 // NOTE: sadly SSL3 and TLS1 differs in how they handle this and
 309                                 // the current design doesn't allow a very cute way to handle
 310                                 // SSL3 alert warning for NoCertificate (41).
 311                                 if (this.context.SecurityProtocol == SecurityProtocolType.Ssl3)
 312                                 {
 313                                         clientCertificate = ((this.context.ClientSettings.Certificates != null) &&
 314                                                 (this.context.ClientSettings.Certificates.Count > 0));
 315                                         // this works well with OpenSSL (but only for SSL3)
 316                                 }
 317
 318                                 if (clientCertificate)
 319                                 {
 320                                         this.protocol.SendRecord(HandshakeType.Certificate);
 321                                 }
 322
 323                                 // Send Client Key Exchange
 324                                 this.protocol.SendRecord(HandshakeType.ClientKeyExchange);
 325
 326                                 // Now initialize session cipher with the generated keys
 327                                 this.context.Cipher.InitializeCipher();
 328
 329                                 // Send certificate verify if requested (optional)
 330                                 if (clientCertificate && (this.context.ClientSettings.ClientCertificate != null))
 331                                 {
 332                                         this.protocol.SendRecord(HandshakeType.CertificateVerify);
 333                                 }
 334
 335                                 // Send Cipher Spec protocol
 336                                 this.protocol.SendChangeCipherSpec ();
 337                                 // Send Finished message
 338                                 this.protocol.SendRecord (HandshakeType.Finished);
 339
 340                                 // Read record until server finished is received
 341                                 while (this.context.HandshakeState != HandshakeState.Finished) {
 342                                         // If all goes well this will process messages:
 343                                         //              Change Cipher Spec
 344                                         //              Server finished
 345                                         SafeReceiveRecord (this.innerStream);
 346                                 }
 347                         }
 348
 349                         // Reset Handshake messages information
 350                         this.context.HandshakeMessages.Reset ();
 351
 352                         // Clear Key Info
 353                         this.context.ClearKeyInfo();
 354
 355                 }
 356
 357                 #endregion
 358
 359                 #region Event Methods
 360
 361                 internal override X509Certificate OnLocalCertificateSelection(X509CertificateCollection clientCertificates, X509Certificate serverCertificate, string targetHost, X509CertificateCollection serverRequestedCertificates)
 362                 {
 363                         if (this.ClientCertSelection != null)
 364                         {
 365                                 return this.ClientCertSelection(
 366                                         clientCertificates,
 367                                         serverCertificate,
 368                                         targetHost,
 369                                         serverRequestedCertificates);
 370                         }
 371
 372                         return null;
 373                 }
 374
 375                 internal override bool OnRemoteCertificateValidation(X509Certificate certificate, int[] errors)
 376                 {
 377                         if (this.ServerCertValidation != null)
 378                         {
 379                                 return this.ServerCertValidation(certificate, errors);
 380                         }
 381
 382                         return (errors != null && errors.Length == 0);
 383                 }
 384
 385                 internal virtual bool RaiseServerCertificateValidation(
 386                         X509Certificate certificate,
 387                         int[]                   certificateErrors)
 388                 {
 389                         return base.RaiseRemoteCertificateValidation(certificate, certificateErrors);
 390                 }
 391
 392                 internal X509Certificate RaiseClientCertificateSelection(
 393                         X509CertificateCollection       clientCertificates,
 394                         X509Certificate                         serverCertificate,
 395                         string                                          targetHost,
 396                         X509CertificateCollection       serverRequestedCertificates)
 397                 {
 398                         return base.RaiseLocalCertificateSelection(clientCertificates, serverCertificate, targetHost, serverRequestedCertificates);
 399                 }
 400
 401                 internal override AsymmetricAlgorithm OnLocalPrivateKeySelection(X509Certificate certificate, string targetHost)
 402                 {
 403                         if (this.PrivateKeySelection != null)
 404                         {
 405                                 return this.PrivateKeySelection(certificate, targetHost);
 406                         }
 407
 408                         return null;
 409                 }
 410
 411                 internal AsymmetricAlgorithm RaisePrivateKeySelection(
 412                         X509Certificate certificate,
 413                         string targetHost)
 414                 {
 415                         return base.RaiseLocalPrivateKeySelection(certificate, targetHost);
 416                 }
 417
 418                 #endregion
 419         }
 420 }