mcs/class/System/System.Net/ServicePointManager.cs

   1 //
   2 // System.Net.ServicePointManager
   3 //
   4 // Authors:
   5 //   Lawrence Pit (loz@cable.a2000.nl)
   6 //   Gonzalo Paniagua Javier (gonzalo@novell.com)
   7 //
   8 // Copyright (c) 2003-2010 Novell, Inc (http://www.novell.com)
   9 //
  10
  11 //
  12 // Permission is hereby granted, free of charge, to any person obtaining
  13 // a copy of this software and associated documentation files (the
  14 // "Software"), to deal in the Software without restriction, including
  15 // without limitation the rights to use, copy, modify, merge, publish,
  16 // distribute, sublicense, and/or sell copies of the Software, and to
  17 // permit persons to whom the Software is furnished to do so, subject to
  18 // the following conditions:
  19 //
  20 // The above copyright notice and this permission notice shall be
  21 // included in all copies or substantial portions of the Software.
  22 //
  23 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  27 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  28 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  29 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  30 //
  31
  32 using System;
  33 using System.Collections;
  34 using System.Collections.Specialized;
  35 using System.Configuration;
  36 using System.Net.Configuration;
  37 using System.Security.Cryptography.X509Certificates;
  38
  39 using System.Globalization;
  40 using System.Net.Security;
  41 #if SECURITY_DEP
  42 using System.Text.RegularExpressions;
  43 using Mono.Security;
  44 using Mono.Security.Cryptography;
  45 using Mono.Security.X509.Extensions;
  46 using Mono.Security.Protocol.Tls;
  47 using MSX = Mono.Security.X509;
  48 #endif
  49
  50 //
  51 // notes:
  52 // A service point manager manages service points (duh!).
  53 // A service point maintains a list of connections (per scheme + authority).
  54 // According to HttpWebRequest.ConnectionGroupName each connection group
  55 // creates additional connections. therefor, a service point has a hashtable
  56 // of connection groups where each value is a list of connections.
  57 //
  58 // when we need to make an HttpWebRequest, we need to do the following:
  59 // 1. find service point, given Uri and Proxy
  60 // 2. find connection group, given service point and group name
  61 // 3. find free connection in connection group, or create one (if ok due to limits)
  62 // 4. lease connection
  63 // 5. execute request
  64 // 6. when finished, return connection
  65 //
  66
  67
  68 namespace System.Net
  69 {
  70 #if MOONLIGHT
  71         internal class ServicePointManager {
  72 #else
  73         public class ServicePointManager {
  74 #endif
  75                 class SPKey {
  76                         Uri uri; // schema/host/port
  77                         bool use_connect;
  78
  79                         public SPKey (Uri uri, bool use_connect) {
  80                                 this.uri = uri;
  81                                 this.use_connect = use_connect;
  82                         }
  83
  84                         public Uri Uri {
  85                                 get { return uri; }
  86                         }
  87
  88                         public bool UseConnect {
  89                                 get { return use_connect; }
  90                         }
  91
  92                         public override int GetHashCode () {
  93                                 return uri.GetHashCode () + ((use_connect) ? 1 : 0);
  94                         }
  95
  96                         public override bool Equals (object obj) {
  97                                 SPKey other = obj as SPKey;
  98                                 if (obj == null) {
  99                                         return false;
 100                                 }
 101
 102                                 return (uri.Equals (other.uri) && other.use_connect == use_connect);
 103                         }
 104                 }
 105
 106                 private static HybridDictionary servicePoints = new HybridDictionary ();
 107
 108                 // Static properties
 109
 110                 private static ICertificatePolicy policy = new DefaultCertificatePolicy ();
 111                 private static int defaultConnectionLimit = DefaultPersistentConnectionLimit;
 112                 private static int maxServicePointIdleTime = 900000; // 15 minutes
 113                 private static int maxServicePoints = 0;
 114                 private static bool _checkCRL = false;
 115                 private static SecurityProtocolType _securityProtocol = SecurityProtocolType.Ssl3 | SecurityProtocolType.Tls;
 116
 117 #if TARGET_JVM
 118                 static bool expectContinue = false;
 119 #else
 120                 static bool expectContinue = true;
 121 #endif
 122                 static bool useNagle;
 123                 static RemoteCertificateValidationCallback server_cert_cb;
 124                 static bool tcp_keepalive;
 125                 static int tcp_keepalive_time;
 126                 static int tcp_keepalive_interval;
 127
 128                 // Fields
 129
 130                 public const int DefaultNonPersistentConnectionLimit = 4;
 131 #if MONOTOUCH
 132                 public const int DefaultPersistentConnectionLimit = 10;
 133 #else
 134                 public const int DefaultPersistentConnectionLimit = 2;
 135 #endif
 136
 137 #if !NET_2_1
 138                 const string configKey = "system.net/connectionManagement";
 139                 static ConnectionManagementData manager;
 140 #endif
 141
 142                 static ServicePointManager ()
 143                 {
 144 #if !NET_2_1
 145 #if CONFIGURATION_DEP
 146                         object cfg = ConfigurationManager.GetSection (configKey);
 147                         ConnectionManagementSection s = cfg as ConnectionManagementSection;
 148                         if (s != null) {
 149                                 manager = new ConnectionManagementData (null);
 150                                 foreach (ConnectionManagementElement e in s.ConnectionManagement)
 151                                         manager.Add (e.Address, e.MaxConnection);
 152
 153                                 defaultConnectionLimit = (int) manager.GetMaxConnections ("*");
 154                                 return;
 155                         }
 156 #endif
 157                         manager = (ConnectionManagementData) ConfigurationSettings.GetConfig (configKey);
 158                         if (manager != null) {
 159                                 defaultConnectionLimit = (int) manager.GetMaxConnections ("*");
 160                         }
 161 #endif
 162                 }
 163
 164                 // Constructors
 165                 private ServicePointManager ()
 166                 {
 167                 }
 168
 169                 // Properties
 170
 171                 [Obsolete ("Use ServerCertificateValidationCallback instead", false)]
 172                 public static ICertificatePolicy CertificatePolicy {
 173                         get { return policy; }
 174                         set { policy = value; }
 175                 }
 176
 177                 [MonoTODO("CRL checks not implemented")]
 178                 public static bool CheckCertificateRevocationList {
 179                         get { return _checkCRL; }
 180                         set { _checkCRL = false; }      // TODO - don't yet accept true
 181                 }
 182
 183                 public static int DefaultConnectionLimit {
 184                         get { return defaultConnectionLimit; }
 185                         set {
 186                                 if (value <= 0)
 187                                         throw new ArgumentOutOfRangeException ("value");
 188
 189                                 defaultConnectionLimit = value;
 190 #if !NET_2_1
 191                 if (manager != null)
 192                                         manager.Add ("*", defaultConnectionLimit);
 193 #endif
 194                         }
 195                 }
 196
 197                 static Exception GetMustImplement ()
 198                 {
 199                         return new NotImplementedException ();
 200                 }
 201
 202                 [MonoTODO]
 203                 public static int DnsRefreshTimeout
 204                 {
 205                         get {
 206                                 throw GetMustImplement ();
 207                         }
 208                         set {
 209                                 throw GetMustImplement ();
 210                         }
 211                 }
 212
 213                 [MonoTODO]
 214                 public static bool EnableDnsRoundRobin
 215                 {
 216                         get {
 217                                 throw GetMustImplement ();
 218                         }
 219                         set {
 220                                 throw GetMustImplement ();
 221                         }
 222                 }
 223
 224                 public static int MaxServicePointIdleTime {
 225                         get {
 226                                 return maxServicePointIdleTime;
 227                         }
 228                         set {
 229                                 if (value < -2 || value > Int32.MaxValue)
 230                                         throw new ArgumentOutOfRangeException ("value");
 231                                 maxServicePointIdleTime = value;
 232                         }
 233                 }
 234
 235                 public static int MaxServicePoints {
 236                         get {
 237                                 return maxServicePoints;
 238                         }
 239                         set {
 240                                 if (value < 0)
 241                                         throw new ArgumentException ("value");
 242
 243                                 maxServicePoints = value;
 244                                 RecycleServicePoints ();
 245                         }
 246                 }
 247
 248 #if NET_1_0
 249                 // we need it for SslClientStream
 250                 internal
 251 #else
 252                 public
 253 #endif
 254                 static SecurityProtocolType SecurityProtocol {
 255                         get { return _securityProtocol; }
 256                         set { _securityProtocol = value; }
 257                 }
 258
 259                 public static RemoteCertificateValidationCallback ServerCertificateValidationCallback
 260                 {
 261                         get {
 262                                 return server_cert_cb;
 263                         }
 264                         set {
 265                                 server_cert_cb = value;
 266                         }
 267                 }
 268
 269                 public static bool Expect100Continue {
 270                         get { return expectContinue; }
 271                         set { expectContinue = value; }
 272                 }
 273
 274                 public static bool UseNagleAlgorithm {
 275                         get { return useNagle; }
 276                         set { useNagle = value; }
 277                 }
 278
 279                 // Methods
 280                 public static void SetTcpKeepAlive (bool enabled, int keepAliveTime, int keepAliveInterval)
 281                 {
 282                         if (enabled) {
 283                                 if (keepAliveTime <= 0)
 284                                         throw new ArgumentOutOfRangeException ("keepAliveTime", "Must be greater than 0");
 285                                 if (keepAliveInterval <= 0)
 286                                         throw new ArgumentOutOfRangeException ("keepAliveInterval", "Must be greater than 0");
 287                         }
 288
 289                         tcp_keepalive = enabled;
 290                         tcp_keepalive_time = keepAliveTime;
 291                         tcp_keepalive_interval = keepAliveInterval;
 292                 }
 293
 294                 public static ServicePoint FindServicePoint (Uri address)
 295                 {
 296                         return FindServicePoint (address, GlobalProxySelection.Select);
 297                 }
 298
 299                 public static ServicePoint FindServicePoint (string uriString, IWebProxy proxy)
 300                 {
 301                         return FindServicePoint (new Uri(uriString), proxy);
 302                 }
 303
 304                 public static ServicePoint FindServicePoint (Uri address, IWebProxy proxy)
 305                 {
 306                         if (address == null)
 307                                 throw new ArgumentNullException ("address");
 308
 309                         RecycleServicePoints ();
 310
 311                         var origAddress = new Uri (address.Scheme + "://" + address.Authority);
 312
 313                         bool usesProxy = false;
 314                         bool useConnect = false;
 315                         if (proxy != null && !proxy.IsBypassed(address)) {
 316                                 usesProxy = true;
 317                                 bool isSecure = address.Scheme == "https";
 318                                 address = proxy.GetProxy (address);
 319                                 if (address.Scheme != "http" && !isSecure)
 320                                         throw new NotSupportedException ("Proxy scheme not supported.");
 321
 322                                 if (isSecure && address.Scheme == "http")
 323                                         useConnect = true;
 324                         }
 325
 326                         address = new Uri (address.Scheme + "://" + address.Authority);
 327
 328                         ServicePoint sp = null;
 329                         lock (servicePoints) {
 330                                 SPKey key = new SPKey (origAddress, useConnect);
 331                                 sp = servicePoints [key] as ServicePoint;
 332                                 if (sp != null)
 333                                         return sp;
 334
 335                                 if (maxServicePoints > 0 && servicePoints.Count >= maxServicePoints)
 336                                         throw new InvalidOperationException ("maximum number of service points reached");
 337
 338                                 string addr = address.ToString ();
 339 #if NET_2_1
 340                                 int limit = defaultConnectionLimit;
 341 #else
 342                                 int limit = (int) manager.GetMaxConnections (addr);
 343 #endif
 344                                 sp = new ServicePoint (address, limit, maxServicePointIdleTime);
 345                                 sp.Expect100Continue = expectContinue;
 346                                 sp.UseNagleAlgorithm = useNagle;
 347                                 sp.UsesProxy = usesProxy;
 348                                 sp.UseConnect = useConnect;
 349                                 sp.SetTcpKeepAlive (tcp_keepalive, tcp_keepalive_time, tcp_keepalive_interval);
 350                                 servicePoints.Add (key, sp);
 351                         }
 352
 353                         return sp;
 354                 }
 355
 356                 // Internal Methods
 357
 358                 internal static void RecycleServicePoints ()
 359                 {
 360                         ArrayList toRemove = new ArrayList ();
 361                         lock (servicePoints) {
 362                                 IDictionaryEnumerator e = servicePoints.GetEnumerator ();
 363                                 while (e.MoveNext ()) {
 364                                         ServicePoint sp = (ServicePoint) e.Value;
 365                                         if (sp.AvailableForRecycling) {
 366                                                 toRemove.Add (e.Key);
 367                                         }
 368                                 }
 369
 370                                 for (int i = 0; i < toRemove.Count; i++)
 371                                         servicePoints.Remove (toRemove [i]);
 372
 373                                 if (maxServicePoints == 0 || servicePoints.Count <= maxServicePoints)
 374                                         return;
 375
 376                                 // get rid of the ones with the longest idle time
 377                                 SortedList list = new SortedList (servicePoints.Count);
 378                                 e = servicePoints.GetEnumerator ();
 379                                 while (e.MoveNext ()) {
 380                                         ServicePoint sp = (ServicePoint) e.Value;
 381                                         if (sp.CurrentConnections == 0) {
 382                                                 while (list.ContainsKey (sp.IdleSince))
 383                                                         sp.IdleSince = sp.IdleSince.AddMilliseconds (1);
 384                                                 list.Add (sp.IdleSince, sp.Address);
 385                                         }
 386                                 }
 387
 388                                 for (int i = 0; i < list.Count && servicePoints.Count > maxServicePoints; i++)
 389                                         servicePoints.Remove (list.GetByIndex (i));
 390                         }
 391                 }
 392 #if MOONLIGHT && SECURITY_DEP
 393                 internal class ChainValidationHelper {
 394                         object sender;
 395
 396                         public ChainValidationHelper (object sender)
 397                         {
 398                                 this.sender = sender;
 399                         }
 400
 401                         // no need to check certificates since we are either
 402                         // (a) loading from the site of origin (and we accepted its certificate to load from it)
 403                         // (b) loading from a cross-domain site and we downloaded the policy file using the browser stack
 404                         //     i.e. the certificate was accepted (or the policy would not be valid)
 405                         internal ValidationResult ValidateChain (Mono.Security.X509.X509CertificateCollection certs)
 406                         {
 407                                 return new ValidationResult (true, false, 0);
 408                         }
 409                 }
 410 #elif SECURITY_DEP
 411                 internal class ChainValidationHelper {
 412                         object sender;
 413                         string host;
 414                         static bool is_macosx = System.IO.File.Exists (MSX.OSX509Certificates.SecurityLibrary);
 415                         static X509RevocationMode revocation_mode;
 416
 417                         static ChainValidationHelper ()
 418                         {
 419 #if !MONOTOUCH
 420                                 revocation_mode = X509RevocationMode.NoCheck;
 421                                 try {
 422                                         string str = Environment.GetEnvironmentVariable ("MONO_X509_REVOCATION_MODE");
 423                                         if (String.IsNullOrEmpty (str))
 424                                                 return;
 425                                         revocation_mode = (X509RevocationMode) Enum.Parse (typeof (X509RevocationMode), str, true);
 426                                 } catch {
 427                                 }
 428 #endif
 429                         }
 430
 431                         public ChainValidationHelper (object sender)
 432                         {
 433                                 this.sender = sender;
 434                         }
 435
 436                         public string Host {
 437                                 get {
 438                                         if (host == null && sender is HttpWebRequest)
 439                                                 host = ((HttpWebRequest) sender).Address.Host;
 440                                         return host;
 441                                 }
 442
 443                                 set { host = value; }
 444                         }
 445
 446                         // Used when the obsolete ICertificatePolicy is set to DefaultCertificatePolicy
 447                         // and the new ServerCertificateValidationCallback is not null
 448                         internal ValidationResult ValidateChain (Mono.Security.X509.X509CertificateCollection certs)
 449                         {
 450                                 // user_denied is true if the user callback is called and returns false
 451                                 bool user_denied = false;
 452                                 if (certs == null || certs.Count == 0)
 453                                         return null;
 454
 455                                 ICertificatePolicy policy = ServicePointManager.CertificatePolicy;
 456                                 RemoteCertificateValidationCallback cb = ServicePointManager.ServerCertificateValidationCallback;
 457
 458                                 X509Certificate2 leaf = new X509Certificate2 (certs [0].RawData);
 459                                 int status11 = 0; // Error code passed to the obsolete ICertificatePolicy callback
 460                                 SslPolicyErrors errors = 0;
 461                                 X509Chain chain = null;
 462                                 bool result = false;
 463 #if MONOTOUCH
 464                                 // The X509Chain is not really usable with MonoTouch (since the decision is not based on this data)
 465                                 // However if someone wants to override the results (good or bad) from iOS then they will want all
 466                                 // the certificates that the server provided (which generally does not include the root) so, only
 467                                 // if there's a user callback, we'll create the X509Chain but won't build it
 468                                 // ref: https://bugzilla.xamarin.com/show_bug.cgi?id=7245
 469                                 if (cb != null) {
 470 #endif
 471                                 chain = new X509Chain ();
 472                                 chain.ChainPolicy = new X509ChainPolicy ();
 473                                 chain.ChainPolicy.RevocationMode = revocation_mode;
 474                                 for (int i = 1; i < certs.Count; i++) {
 475                                         X509Certificate2 c2 = new X509Certificate2 (certs [i].RawData);
 476                                         chain.ChainPolicy.ExtraStore.Add (c2);
 477                                 }
 478 #if MONOTOUCH
 479                                 }
 480 #else
 481                                 try {
 482                                         if (!chain.Build (leaf))
 483                                                 errors |= GetErrorsFromChain (chain);
 484                                 } catch (Exception e) {
 485                                         Console.Error.WriteLine ("ERROR building certificate chain: {0}", e);
 486                                         Console.Error.WriteLine ("Please, report this problem to the Mono team");
 487                                         errors |= SslPolicyErrors.RemoteCertificateChainErrors;
 488                                 }
 489
 490                                 // for OSX and iOS we're using the native API to check for the SSL server policy and host names
 491                                 if (!is_macosx) {
 492                                         if (!CheckCertificateUsage (leaf)) {
 493                                                 errors |= SslPolicyErrors.RemoteCertificateChainErrors;
 494                                                 status11 = -2146762490; //CERT_E_PURPOSE 0x800B0106
 495                                         }
 496
 497                                         if (!CheckServerIdentity (certs [0], Host)) {
 498                                                 errors |= SslPolicyErrors.RemoteCertificateNameMismatch;
 499                                                 status11 = -2146762481; // CERT_E_CN_NO_MATCH 0x800B010F
 500                                         }
 501                                 } else {
 502 #endif
 503                                         // Attempt to use OSX certificates
 504                                         // Ideally we should return the SecTrustResult
 505                                         MSX.OSX509Certificates.SecTrustResult trustResult = MSX.OSX509Certificates.SecTrustResult.Deny;
 506                                         try {
 507                                                 trustResult = MSX.OSX509Certificates.TrustEvaluateSsl (certs, Host);
 508                                                 // We could use the other values of trustResult to pass this extra information
 509                                                 // to the .NET 2 callback for values like SecTrustResult.Confirm
 510                                                 result = (trustResult == MSX.OSX509Certificates.SecTrustResult.Proceed ||
 511                                                                   trustResult == MSX.OSX509Certificates.SecTrustResult.Unspecified);
 512                                         } catch {
 513                                                 // Ignore
 514                                         }
 515
 516                                         if (result) {
 517                                                 // TrustEvaluateSsl was successful so there's no trust error
 518                                                 // IOW we discard our own chain (since we trust OSX one instead)
 519                                                 errors = 0;
 520                                         } else {
 521                                                 // callback and DefaultCertificatePolicy needs this since 'result' is not specified
 522                                                 status11 = (int) trustResult;
 523                                                 errors |= SslPolicyErrors.RemoteCertificateChainErrors;
 524                                         }
 525 #if !MONOTOUCH
 526                                 }
 527 #endif
 528
 529 #if MONODROID
 530                                 result = AndroidPlatform.TrustEvaluateSsl (certs, sender, leaf, chain, errors);
 531                                 if (result) {
 532                                         // chain.Build() + GetErrorsFromChain() (above) will ALWAYS fail on
 533                                         // Android (there are no mozroots or preinstalled root certificates),
 534                                         // thus `errors` will ALWAYS have RemoteCertificateChainErrors.
 535                                         // Android just verified the chain; clear RemoteCertificateChainErrors.
 536                                         errors  &= ~SslPolicyErrors.RemoteCertificateChainErrors;
 537                                 }
 538 #endif
 539
 540                                 if (policy != null && (!(policy is DefaultCertificatePolicy) || cb == null)) {
 541                                         ServicePoint sp = null;
 542                                         HttpWebRequest req = sender as HttpWebRequest;
 543                                         if (req != null)
 544                                                 sp = req.ServicePointNoLock;
 545                                         if (status11 == 0 && errors != 0)
 546                                                 status11 = GetStatusFromChain (chain);
 547
 548                                         // pre 2.0 callback
 549                                         result = policy.CheckValidationResult (sp, leaf, req, status11);
 550                                         user_denied = !result && !(policy is DefaultCertificatePolicy);
 551                                 }
 552                                 // If there's a 2.0 callback, it takes precedence
 553                                 if (cb != null) {
 554                                         result = cb (sender, leaf, chain, errors);
 555                                         user_denied = !result;
 556                                 }
 557                                 return new ValidationResult (result, user_denied, status11);
 558                         }
 559
 560                         static int GetStatusFromChain (X509Chain chain)
 561                         {
 562                                 long result = 0;
 563                                 foreach (var status in chain.ChainStatus) {
 564                                         X509ChainStatusFlags flags = status.Status;
 565                                         if (flags == X509ChainStatusFlags.NoError)
 566                                                 continue;
 567
 568                                         // CERT_E_EXPIRED
 569                                         if ((flags & X509ChainStatusFlags.NotTimeValid) != 0) result = 0x800B0101;
 570                                         // CERT_E_VALIDITYPERIODNESTING
 571                                         else if ((flags & X509ChainStatusFlags.NotTimeNested) != 0) result = 0x800B0102;
 572                                         // CERT_E_REVOKED
 573                                         else if ((flags & X509ChainStatusFlags.Revoked) != 0) result = 0x800B010C;
 574                                         // TRUST_E_CERT_SIGNATURE
 575                                         else if ((flags & X509ChainStatusFlags.NotSignatureValid) != 0) result = 0x80096004;
 576                                         // CERT_E_WRONG_USAGE
 577                                         else if ((flags & X509ChainStatusFlags.NotValidForUsage) != 0) result = 0x800B0110;
 578                                         // CERT_E_UNTRUSTEDROOT
 579                                         else if ((flags & X509ChainStatusFlags.UntrustedRoot) != 0) result = 0x800B0109;
 580                                         // CRYPT_E_NO_REVOCATION_CHECK
 581                                         else if ((flags & X509ChainStatusFlags.RevocationStatusUnknown) != 0) result = 0x80092012;
 582                                         // CERT_E_CHAINING
 583                                         else if ((flags & X509ChainStatusFlags.Cyclic) != 0) result = 0x800B010A;
 584                                         // TRUST_E_FAIL - generic
 585                                         else if ((flags & X509ChainStatusFlags.InvalidExtension) != 0) result = 0x800B010B;
 586                                         // CERT_E_UNTRUSTEDROOT
 587                                         else if ((flags & X509ChainStatusFlags.InvalidPolicyConstraints) != 0) result = 0x800B010D;
 588                                         // TRUST_E_BASIC_CONSTRAINTS
 589                                         else if ((flags & X509ChainStatusFlags.InvalidBasicConstraints) != 0) result = 0x80096019;
 590                                         // CERT_E_INVALID_NAME
 591                                         else if ((flags & X509ChainStatusFlags.InvalidNameConstraints) != 0) result = 0x800B0114;
 592                                         // CERT_E_INVALID_NAME
 593                                         else if ((flags & X509ChainStatusFlags.HasNotSupportedNameConstraint) != 0) result = 0x800B0114;
 594                                         // CERT_E_INVALID_NAME
 595                                         else if ((flags & X509ChainStatusFlags.HasNotDefinedNameConstraint) != 0) result = 0x800B0114;
 596                                         // CERT_E_INVALID_NAME
 597                                         else if ((flags & X509ChainStatusFlags.HasNotPermittedNameConstraint) != 0) result = 0x800B0114;
 598                                         // CERT_E_INVALID_NAME
 599                                         else if ((flags & X509ChainStatusFlags.HasExcludedNameConstraint) != 0) result = 0x800B0114;
 600                                         // CERT_E_CHAINING
 601                                         else if ((flags & X509ChainStatusFlags.PartialChain) != 0) result = 0x800B010A;
 602                                         // CERT_E_EXPIRED
 603                                         else if ((flags & X509ChainStatusFlags.CtlNotTimeValid) != 0) result = 0x800B0101;
 604                                         // TRUST_E_CERT_SIGNATURE
 605                                         else if ((flags & X509ChainStatusFlags.CtlNotSignatureValid) != 0) result = 0x80096004;
 606                                         // CERT_E_WRONG_USAGE
 607                                         else if ((flags & X509ChainStatusFlags.CtlNotValidForUsage) != 0) result = 0x800B0110;
 608                                         // CRYPT_E_NO_REVOCATION_CHECK
 609                                         else if ((flags & X509ChainStatusFlags.OfflineRevocation) != 0) result = 0x80092012;
 610                                         // CERT_E_ISSUERCHAINING
 611                                         else if ((flags & X509ChainStatusFlags.NoIssuanceChainPolicy) != 0) result = 0x800B0107;
 612                                         else result = 0x800B010B; // TRUST_E_FAIL - generic
 613
 614                                         break; // Exit the loop on the first error
 615                                 }
 616                                 return (int) result;
 617                         }
 618 #if !MONOTOUCH
 619                         static SslPolicyErrors GetErrorsFromChain (X509Chain chain)
 620                         {
 621                                 SslPolicyErrors errors = SslPolicyErrors.None;
 622                                 foreach (var status in chain.ChainStatus) {
 623                                         if (status.Status == X509ChainStatusFlags.NoError)
 624                                                 continue;
 625                                         errors |= SslPolicyErrors.RemoteCertificateChainErrors;
 626                                         break;
 627                                 }
 628                                 return errors;
 629                         }
 630
 631                         static X509KeyUsageFlags s_flags = X509KeyUsageFlags.DigitalSignature  |
 632                                                         X509KeyUsageFlags.KeyAgreement |
 633                                                         X509KeyUsageFlags.KeyEncipherment;
 634                         // Adapted to System 2.0+ from TlsServerCertificate.cs
 635                         //------------------------------
 636                         // Note: this method only works for RSA certificates
 637                         // DH certificates requires some changes - does anyone use one ?
 638                         static bool CheckCertificateUsage (X509Certificate2 cert)
 639                         {
 640                                 try {
 641                                         // certificate extensions are required for this
 642                                         // we "must" accept older certificates without proofs
 643                                         if (cert.Version < 3)
 644                                                 return true;
 645
 646                                         X509KeyUsageExtension kux = (cert.Extensions ["2.5.29.15"] as X509KeyUsageExtension);
 647                                         X509EnhancedKeyUsageExtension eku = (cert.Extensions ["2.5.29.37"] as X509EnhancedKeyUsageExtension);
 648                                         if (kux != null && eku != null) {
 649                                                 // RFC3280 states that when both KeyUsageExtension and
 650                                                 // ExtendedKeyUsageExtension are present then BOTH should
 651                                                 // be valid
 652                                                 if ((kux.KeyUsages & s_flags) == 0)
 653                                                         return false;
 654                                                 return eku.EnhancedKeyUsages ["1.3.6.1.5.5.7.3.1"] != null ||
 655                                                         eku.EnhancedKeyUsages ["2.16.840.1.113730.4.1"] != null;
 656                                         } else if (kux != null) {
 657                                                 return ((kux.KeyUsages & s_flags) != 0);
 658                                         } else if (eku != null) {
 659                                                 // Server Authentication (1.3.6.1.5.5.7.3.1) or
 660                                                 // Netscape Server Gated Crypto (2.16.840.1.113730.4)
 661                                                 return eku.EnhancedKeyUsages ["1.3.6.1.5.5.7.3.1"] != null ||
 662                                                         eku.EnhancedKeyUsages ["2.16.840.1.113730.4.1"] != null;
 663                                         }
 664
 665                                         // last chance - try with older (deprecated) Netscape extensions
 666                                         X509Extension ext = cert.Extensions ["2.16.840.1.113730.1.1"];
 667                                         if (ext != null) {
 668                                                 string text = ext.NetscapeCertType (false);
 669                                                 return text.IndexOf ("SSL Server Authentication", StringComparison.Ordinal) != -1;
 670                                         }
 671                                         return true;
 672                                 } catch (Exception e) {
 673                                         Console.Error.WriteLine ("ERROR processing certificate: {0}", e);
 674                                         Console.Error.WriteLine ("Please, report this problem to the Mono team");
 675                                         return false;
 676                                 }
 677                         }
 678
 679                         // RFC2818 - HTTP Over TLS, Section 3.1
 680                         // http://www.ietf.org/rfc/rfc2818.txt
 681                         //
 682                         // 1.   if present MUST use subjectAltName dNSName as identity
 683                         // 1.1.         if multiples entries a match of any one is acceptable
 684                         // 1.2.         wildcard * is acceptable
 685                         // 2.   URI may be an IP address -> subjectAltName.iPAddress
 686                         // 2.1.         exact match is required
 687                         // 3.   Use of the most specific Common Name (CN=) in the Subject
 688                         // 3.1          Existing practice but DEPRECATED
 689                         static bool CheckServerIdentity (Mono.Security.X509.X509Certificate cert, string targetHost)
 690                         {
 691                                 try {
 692                                         Mono.Security.X509.X509Extension ext = cert.Extensions ["2.5.29.17"];
 693                                         // 1. subjectAltName
 694                                         if (ext != null) {
 695                                                 SubjectAltNameExtension subjectAltName = new SubjectAltNameExtension (ext);
 696                                                 // 1.1 - multiple dNSName
 697                                                 foreach (string dns in subjectAltName.DNSNames) {
 698                                                         // 1.2 TODO - wildcard support
 699                                                         if (Match (targetHost, dns))
 700                                                                 return true;
 701                                                 }
 702                                                 // 2. ipAddress
 703                                                 foreach (string ip in subjectAltName.IPAddresses) {
 704                                                         // 2.1. Exact match required
 705                                                         if (ip == targetHost)
 706                                                                 return true;
 707                                                 }
 708                                         }
 709                                         // 3. Common Name (CN=)
 710                                         return CheckDomainName (cert.SubjectName, targetHost);
 711                                 } catch (Exception e) {
 712                                         Console.Error.WriteLine ("ERROR processing certificate: {0}", e);
 713                                         Console.Error.WriteLine ("Please, report this problem to the Mono team");
 714                                         return false;
 715                                 }
 716                         }
 717
 718                         static bool CheckDomainName (string subjectName, string targetHost)
 719                         {
 720                                 string  domainName = String.Empty;
 721                                 Regex search = new Regex(@"CN\s*=\s*([^,]*)");
 722                                 MatchCollection elements = search.Matches(subjectName);
 723                                 if (elements.Count == 1) {
 724                                         if (elements[0].Success)
 725                                                 domainName = elements[0].Groups[1].Value.ToString();
 726                                 }
 727
 728                                 return Match (targetHost, domainName);
 729                         }
 730
 731                         // ensure the pattern is valid wrt to RFC2595 and RFC2818
 732                         // http://www.ietf.org/rfc/rfc2595.txt
 733                         // http://www.ietf.org/rfc/rfc2818.txt
 734                         static bool Match (string hostname, string pattern)
 735                         {
 736                                 // check if this is a pattern
 737                                 int index = pattern.IndexOf ('*');
 738                                 if (index == -1) {
 739                                         // not a pattern, do a direct case-insensitive comparison
 740                                         return (String.Compare (hostname, pattern, true, CultureInfo.InvariantCulture) == 0);
 741                                 }
 742
 743                                 // check pattern validity
 744                                 // A "*" wildcard character MAY be used as the left-most name component in the certificate.
 745
 746                                 // unless this is the last char (valid)
 747                                 if (index != pattern.Length - 1) {
 748                                         // then the next char must be a dot .'.
 749                                         if (pattern [index + 1] != '.')
 750                                                 return false;
 751                                 }
 752
 753                                 // only one (A) wildcard is supported
 754                                 int i2 = pattern.IndexOf ('*', index + 1);
 755                                 if (i2 != -1)
 756                                         return false;
 757
 758                                 // match the end of the pattern
 759                                 string end = pattern.Substring (index + 1);
 760                                 int length = hostname.Length - end.Length;
 761                                 // no point to check a pattern that is longer than the hostname
 762                                 if (length <= 0)
 763                                         return false;
 764
 765                                 if (String.Compare (hostname, length, end, 0, end.Length, true, CultureInfo.InvariantCulture) != 0)
 766                                         return false;
 767
 768                                 // special case, we start with the wildcard
 769                                 if (index == 0) {
 770                                         // ensure we hostname non-matched part (start) doesn't contain a dot
 771                                         int i3 = hostname.IndexOf ('.');
 772                                         return ((i3 == -1) || (i3 >= (hostname.Length - end.Length)));
 773                                 }
 774
 775                                 // match the start of the pattern
 776                                 string start = pattern.Substring (0, index);
 777                                 return (String.Compare (hostname, 0, start, 0, start.Length, true, CultureInfo.InvariantCulture) == 0);
 778                         }
 779 #endif
 780                 }
 781 #endif
 782         }
 783 }
 784