mcs/class/System/Mono.Net.Security/ChainValidationHelper.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 #if SECURITY_DEP
  33
  34 #if MONO_SECURITY_ALIAS
  35 extern alias MonoSecurity;
  36 #endif
  37
  38 #if MONO_SECURITY_ALIAS
  39 using MonoSecurity::Mono.Security.Interface;
  40 using MSX = MonoSecurity::Mono.Security.X509;
  41 using MonoSecurity::Mono.Security.X509.Extensions;
  42 #else
  43 using Mono.Security.Interface;
  44 using MSX = Mono.Security.X509;
  45 using Mono.Security.X509.Extensions;
  46 #endif
  47
  48 using System;
  49 using System.Net;
  50 using System.Threading;
  51 using System.Collections;
  52 using System.Collections.Generic;
  53 using System.Collections.Specialized;
  54 using System.Configuration;
  55 using System.Net.Configuration;
  56 using System.Text.RegularExpressions;
  57 using System.Security.Cryptography.X509Certificates;
  58
  59 using System.Globalization;
  60 using System.Net.Security;
  61 using System.Diagnostics;
  62
  63 namespace Mono.Net.Security
  64 {
  65         internal delegate bool ServerCertValidationCallbackWrapper (ServerCertValidationCallback callback, X509Certificate certificate, X509Chain chain, MonoSslPolicyErrors sslPolicyErrors);
  66
  67         internal class ChainValidationHelper : ICertificateValidator2
  68         {
  69                 readonly object sender;
  70                 readonly MonoTlsSettings settings;
  71                 readonly MonoTlsProvider provider;
  72                 readonly ServerCertValidationCallback certValidationCallback;
  73                 readonly LocalCertSelectionCallback certSelectionCallback;
  74                 readonly ServerCertValidationCallbackWrapper callbackWrapper;
  75                 readonly MonoTlsStream tlsStream;
  76                 readonly HttpWebRequest request;
  77
  78                 internal static ICertificateValidator GetInternalValidator (MonoTlsProvider provider, MonoTlsSettings settings)
  79                 {
  80                         if (settings == null)
  81                                 return new ChainValidationHelper (provider, null, false, null, null);
  82                         if (settings.CertificateValidator != null)
  83                                 return settings.CertificateValidator;
  84                         return new ChainValidationHelper (provider, settings, false, null, null);
  85                 }
  86
  87                 internal static ICertificateValidator GetDefaultValidator (MonoTlsSettings settings)
  88                 {
  89                         var provider = MonoTlsProviderFactory.GetProvider ();
  90                         if (settings == null)
  91                                 return new ChainValidationHelper (provider, null, false, null, null);
  92                         if (settings.CertificateValidator != null)
  93                                 throw new NotSupportedException ();
  94                         return new ChainValidationHelper (provider, settings, false, null, null);
  95                 }
  96
  97 #region SslStream support
  98
  99                 /*
 100                  * This is a hack which is used in SslStream - see ReferenceSources/SslStream.cs for details.
 101                  */
 102                 internal static ChainValidationHelper CloneWithCallbackWrapper (MonoTlsProvider provider, ref MonoTlsSettings settings, ServerCertValidationCallbackWrapper wrapper)
 103                 {
 104                         var helper = (ChainValidationHelper)settings.CertificateValidator;
 105                         if (helper == null)
 106                                 helper = new ChainValidationHelper (provider, settings, true, null, wrapper);
 107                         else
 108                                 helper = new ChainValidationHelper (helper, provider, settings, wrapper);
 109                         settings = helper.settings;
 110                         return helper;
 111                 }
 112
 113                 internal static bool InvokeCallback (ServerCertValidationCallback callback, object sender, X509Certificate certificate, X509Chain chain, MonoSslPolicyErrors sslPolicyErrors)
 114                 {
 115                         return callback.Invoke (sender, certificate, chain, (SslPolicyErrors)sslPolicyErrors);
 116                 }
 117
 118 #endregion
 119
 120                 ChainValidationHelper (ChainValidationHelper other, MonoTlsProvider provider, MonoTlsSettings settings, ServerCertValidationCallbackWrapper callbackWrapper = null)
 121                 {
 122                         sender = other.sender;
 123                         certValidationCallback = other.certValidationCallback;
 124                         certSelectionCallback = other.certSelectionCallback;
 125                         tlsStream = other.tlsStream;
 126                         request = other.request;
 127
 128                         if (settings == null)
 129                                 settings = MonoTlsSettings.DefaultSettings;
 130
 131                         this.provider = provider;
 132                         this.settings = settings.CloneWithValidator (this);
 133                         this.callbackWrapper = callbackWrapper;
 134                 }
 135
 136                 internal static ChainValidationHelper Create (MonoTlsProvider provider, ref MonoTlsSettings settings, MonoTlsStream stream)
 137                 {
 138                         var helper = new ChainValidationHelper (provider, settings, true, stream, null);
 139                         settings = helper.settings;
 140                         return helper;
 141                 }
 142
 143                 ChainValidationHelper (MonoTlsProvider provider, MonoTlsSettings settings, bool cloneSettings, MonoTlsStream stream, ServerCertValidationCallbackWrapper callbackWrapper)
 144                 {
 145                         if (settings == null)
 146                                 settings = MonoTlsSettings.CopyDefaultSettings ();
 147                         if (cloneSettings)
 148                                 settings = settings.CloneWithValidator (this);
 149                         if (provider == null)
 150                                 provider = MonoTlsProviderFactory.GetProvider ();
 151
 152                         this.provider = provider;
 153                         this.settings = settings;
 154                         this.tlsStream = stream;
 155                         this.callbackWrapper = callbackWrapper;
 156
 157                         var fallbackToSPM = false;
 158
 159                         if (settings != null) {
 160                                 if (settings.RemoteCertificateValidationCallback != null) {
 161                                         var callback = Private.CallbackHelpers.MonoToPublic (settings.RemoteCertificateValidationCallback);
 162                                         certValidationCallback = new ServerCertValidationCallback (callback);
 163                                 }
 164                                 certSelectionCallback = Private.CallbackHelpers.MonoToInternal (settings.ClientCertificateSelectionCallback);
 165                                 fallbackToSPM = settings.UseServicePointManagerCallback ?? stream != null;
 166                         }
 167
 168                         if (stream != null) {
 169                                 this.request = stream.Request;
 170                                 this.sender = request;
 171
 172                                 if (certValidationCallback == null)
 173                                         certValidationCallback = request.ServerCertValidationCallback;
 174                                 if (certSelectionCallback == null)
 175                                         certSelectionCallback = new LocalCertSelectionCallback (DefaultSelectionCallback);
 176
 177                                 if (settings == null)
 178                                         fallbackToSPM = true;
 179                         }
 180
 181                         if (fallbackToSPM && certValidationCallback == null)
 182                                 certValidationCallback = ServicePointManager.ServerCertValidationCallback;
 183                 }
 184
 185                 static X509Certificate DefaultSelectionCallback (string targetHost, X509CertificateCollection localCertificates, X509Certificate remoteCertificate, string[] acceptableIssuers)
 186                 {
 187                         X509Certificate clientCertificate;
 188                         if (localCertificates == null || localCertificates.Count == 0)
 189                                 clientCertificate = null;
 190                         else
 191                                 clientCertificate = localCertificates [0];
 192                         return clientCertificate;
 193                 }
 194
 195                 public MonoTlsProvider Provider {
 196                         get { return provider; }
 197                 }
 198
 199                 public MonoTlsSettings Settings {
 200                         get { return settings; }
 201                 }
 202
 203                 public bool HasCertificateSelectionCallback {
 204                         get { return certSelectionCallback != null; }
 205                 }
 206
 207                 public bool SelectClientCertificate (
 208                         string targetHost, X509CertificateCollection localCertificates, X509Certificate remoteCertificate,
 209                         string[] acceptableIssuers, out X509Certificate clientCertificate)
 210                 {
 211                         if (certSelectionCallback == null) {
 212                                 clientCertificate = null;
 213                                 return false;
 214                         }
 215                         clientCertificate = certSelectionCallback (targetHost, localCertificates, remoteCertificate, acceptableIssuers);
 216                         return true;
 217                 }
 218
 219                 internal X509Certificate SelectClientCertificate (
 220                         string targetHost, X509CertificateCollection localCertificates, X509Certificate remoteCertificate,
 221                         string[] acceptableIssuers)
 222                 {
 223                         if (certSelectionCallback == null)
 224                                 return null;
 225                         return certSelectionCallback (targetHost, localCertificates, remoteCertificate, acceptableIssuers);
 226                 }
 227
 228                 internal bool ValidateClientCertificate (X509Certificate certificate, MonoSslPolicyErrors errors)
 229                 {
 230                         var certs = new X509CertificateCollection ();
 231                         certs.Add (new X509Certificate2 (certificate.GetRawCertData ()));
 232
 233                         var result = ValidateChain (string.Empty, true, certificate, null, certs, (SslPolicyErrors)errors);
 234                         if (result == null)
 235                                 return false;
 236
 237                         return result.Trusted && !result.UserDenied;
 238                 }
 239
 240                 public ValidationResult ValidateCertificate (string host, bool serverMode, X509CertificateCollection certs)
 241                 {
 242                         try {
 243                                 X509Certificate leaf;
 244                                 if (certs != null && certs.Count != 0)
 245                                         leaf = certs [0];
 246                                 else
 247                                         leaf = null;
 248                                 var result = ValidateChain (host, serverMode, leaf, null, certs, 0);
 249                                 if (tlsStream != null)
 250                                         tlsStream.CertificateValidationFailed = result == null || !result.Trusted || result.UserDenied;
 251                                 return result;
 252                         } catch {
 253                                 if (tlsStream != null)
 254                                         tlsStream.CertificateValidationFailed = true;
 255                                 throw;
 256                         }
 257                 }
 258
 259                 public ValidationResult ValidateCertificate (string host, bool serverMode, X509Certificate leaf, X509Chain chain)
 260                 {
 261                         try {
 262                                 var result = ValidateChain (host, serverMode, leaf, chain, null, 0);
 263                                 if (tlsStream != null)
 264                                         tlsStream.CertificateValidationFailed = result == null || !result.Trusted || result.UserDenied;
 265                                 return result;
 266                         } catch {
 267                                 if (tlsStream != null)
 268                                         tlsStream.CertificateValidationFailed = true;
 269                                 throw;
 270                         }
 271                 }
 272
 273                 ValidationResult ValidateChain (string host, bool server, X509Certificate leaf,
 274                                                 X509Chain chain, X509CertificateCollection certs,
 275                                                 SslPolicyErrors errors)
 276                 {
 277                         var oldChain = chain;
 278                         var ownsChain = chain == null;
 279                         try {
 280                                 var result = ValidateChain (host, server, leaf, ref chain, certs, errors);
 281                                 if (chain != oldChain)
 282                                         ownsChain = true;
 283
 284                                 return result;
 285                         } finally {
 286                                 // If ValidateChain() changed the chain, then we need to free it.
 287                                 if (ownsChain && chain != null)
 288                                         chain.Dispose ();
 289                         }
 290                 }
 291
 292                 ValidationResult ValidateChain (string host, bool server, X509Certificate leaf,
 293                                                 ref X509Chain chain, X509CertificateCollection certs,
 294                                                 SslPolicyErrors errors)
 295                 {
 296                         // user_denied is true if the user callback is called and returns false
 297                         bool user_denied = false;
 298                         bool result = false;
 299
 300                         var hasCallback = certValidationCallback != null || callbackWrapper != null;
 301
 302                         if (tlsStream != null)
 303                                 request.ServicePoint.UpdateServerCertificate (leaf);
 304
 305                         if (leaf == null) {
 306                                 errors |= SslPolicyErrors.RemoteCertificateNotAvailable;
 307                                 if (hasCallback) {
 308                                         if (callbackWrapper != null)
 309                                                 result = callbackWrapper.Invoke (certValidationCallback, leaf, null, (MonoSslPolicyErrors)errors);
 310                                         else
 311                                                 result = certValidationCallback.Invoke (sender, leaf, null, errors);
 312                                         user_denied = !result;
 313                                 }
 314                                 return new ValidationResult (result, user_denied, 0, (MonoSslPolicyErrors)errors);
 315                         }
 316
 317                         // Ignore port number when validating certificates.
 318                         if (!string.IsNullOrEmpty (host)) {
 319                                 var pos = host.IndexOf (':');
 320                                 if (pos > 0)
 321                                         host = host.Substring (0, pos);
 322                         }
 323
 324                         ICertificatePolicy policy = ServicePointManager.GetLegacyCertificatePolicy ();
 325
 326                         int status11 = 0; // Error code passed to the obsolete ICertificatePolicy callback
 327
 328                         bool wantsChain = SystemCertificateValidator.NeedsChain (settings);
 329                         if (!wantsChain && hasCallback) {
 330                                 if (settings == null || settings.CallbackNeedsCertificateChain)
 331                                         wantsChain = true;
 332                         }
 333
 334                         var xerrors = (MonoSslPolicyErrors)errors;
 335                         result = provider.ValidateCertificate (this, host, server, certs, wantsChain, ref chain, ref xerrors, ref status11);
 336                         errors = (SslPolicyErrors)xerrors;
 337
 338                         if (policy != null && (!(policy is DefaultCertificatePolicy) || certValidationCallback == null)) {
 339                                 ServicePoint sp = null;
 340                                 if (request != null)
 341                                         sp = request.ServicePointNoLock;
 342                                 if (status11 == 0 && errors != 0) {
 343                                         // TRUST_E_FAIL
 344                                         status11 = unchecked ((int)0x800B010B);
 345                                 }
 346
 347                                 // pre 2.0 callback
 348                                 result = policy.CheckValidationResult (sp, leaf, request, status11);
 349                                 user_denied = !result && !(policy is DefaultCertificatePolicy);
 350                         }
 351                         // If there's a 2.0 callback, it takes precedence
 352                         if (hasCallback) {
 353                                 if (callbackWrapper != null)
 354                                         result = callbackWrapper.Invoke (certValidationCallback, leaf, chain, (MonoSslPolicyErrors)errors);
 355                                 else
 356                                         result = certValidationCallback.Invoke (sender, leaf, chain, errors);
 357                                 user_denied = !result;
 358                         }
 359                         return new ValidationResult (result, user_denied, status11, (MonoSslPolicyErrors)errors);
 360                 }
 361
 362                 bool InvokeSystemValidator (string targetHost, bool serverMode, X509CertificateCollection certificates, X509Chain chain, ref MonoSslPolicyErrors xerrors, ref int status11)
 363                 {
 364                         var errors = (SslPolicyErrors)xerrors;
 365                         var result = SystemCertificateValidator.Evaluate (settings, targetHost, certificates, chain, ref errors, ref status11);
 366                         xerrors = (MonoSslPolicyErrors)errors;
 367                         return result;
 368                 }
 369         }
 370 }
 371 #endif
 372