mcs/class/System/Mono.Btls/MonoBtlsContext.cs

   1 //
   2 // MonoBtlsContext.cs
   3 //
   4 // Author:
   5 //       Martin Baulig <martin.baulig@xamarin.com>
   6 //
   7 // Copyright (c) 2016 Xamarin Inc. (http://www.xamarin.com)
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining a copy
  10 // of this software and associated documentation files (the "Software"), to deal
  11 // in the Software without restriction, including without limitation the rights
  12 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  13 // copies of the Software, and to permit persons to whom the Software is
  14 // furnished to do so, subject to the following conditions:
  15 //
  16 // The above copyright notice and this permission notice shall be included in
  17 // all copies or substantial portions of the Software.
  18 //
  19 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  20 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  22 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  23 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  24 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  25 // THE SOFTWARE.
  26 #if SECURITY_DEP && MONO_FEATURE_BTLS
  27 #if MONO_SECURITY_ALIAS
  28 extern alias MonoSecurity;
  29 #endif
  30
  31 using System;
  32 using System.IO;
  33 using System.Threading;
  34 using System.Threading.Tasks;
  35 using System.Security.Cryptography.X509Certificates;
  36 using System.Security.Authentication;
  37 using System.Runtime.InteropServices;
  38
  39 #if MONO_SECURITY_ALIAS
  40 using MonoSecurity::Mono.Security.Interface;
  41 #else
  42 using Mono.Security.Interface;
  43 #endif
  44
  45 using MNS = Mono.Net.Security;
  46
  47 namespace Mono.Btls
  48 {
  49         class MonoBtlsContext : MNS.MobileTlsContext, IMonoBtlsBioMono
  50         {
  51                 X509Certificate remoteCertificate;
  52                 X509Certificate clientCertificate;
  53                 X509CertificateImplBtls nativeServerCertificate;
  54                 X509CertificateImplBtls nativeClientCertificate;
  55                 MonoBtlsSslCtx ctx;
  56                 MonoBtlsSsl ssl;
  57                 MonoBtlsBio bio;
  58                 MonoBtlsBio errbio;
  59
  60                 MonoTlsConnectionInfo connectionInfo;
  61                 bool certificateValidated;
  62                 bool isAuthenticated;
  63                 bool connected;
  64
  65                 public MonoBtlsContext (
  66                         MNS.MobileAuthenticatedStream parent,
  67                         bool serverMode, string targetHost,
  68                         SslProtocols enabledProtocols, X509Certificate serverCertificate,
  69                         X509CertificateCollection clientCertificates, bool askForClientCert)
  70                         : base (parent, serverMode, targetHost, enabledProtocols,
  71                                 serverCertificate, clientCertificates, askForClientCert)
  72                 {
  73                         if (serverMode)
  74                                 nativeServerCertificate = GetPrivateCertificate (serverCertificate);
  75                 }
  76
  77                 static X509CertificateImplBtls GetPrivateCertificate (X509Certificate certificate)
  78                 {
  79                         var impl = certificate.Impl as X509CertificateImplBtls;
  80                         if (impl != null)
  81                                 return (X509CertificateImplBtls)impl.Clone ();
  82
  83                         var password = Guid.NewGuid ().ToString ();
  84                         var buffer = certificate.Export (X509ContentType.Pfx, password);
  85
  86                         impl = new X509CertificateImplBtls ();
  87                         impl.Import (buffer, password, X509KeyStorageFlags.DefaultKeySet);
  88                         return impl;
  89                 }
  90
  91                 new public MonoBtlsProvider Provider {
  92                         get { return (MonoBtlsProvider)base.Provider; }
  93                 }
  94
  95                 int VerifyCallback (MonoBtlsX509StoreCtx storeCtx)
  96                 {
  97                         using (var chainImpl = new X509ChainImplBtls (storeCtx))
  98                         using (var managedChain = new X509Chain (chainImpl)) {
  99                                 var leaf = managedChain.ChainElements[0].Certificate;
 100                                 var result = ValidateCertificate (leaf, managedChain);
 101                                 certificateValidated = true;
 102                                 return result ? 1 : 0;
 103                         }
 104                 }
 105
 106                 int SelectCallback ()
 107                 {
 108                         Debug ("SELECT CALLBACK!");
 109
 110                         GetPeerCertificate ();
 111                         if (remoteCertificate == null)
 112                                 throw new TlsException (AlertDescription.InternalError, "Cannot request client certificate before receiving one from the server.");
 113
 114                         var clientCert = SelectClientCertificate (remoteCertificate, null);
 115                         Debug ("SELECT CALLBACK #1: {0}", clientCert);
 116                         if (clientCert == null)
 117                                 return 1;
 118
 119                         nativeClientCertificate = GetPrivateCertificate (clientCert);
 120                         Debug ("SELECT CALLBACK #2: {0}", nativeClientCertificate);
 121                         clientCertificate = new X509Certificate (nativeClientCertificate);
 122                         SetPrivateCertificate (nativeClientCertificate);
 123                         return 1;
 124                 }
 125
 126                 public override void StartHandshake ()
 127                 {
 128                         InitializeConnection ();
 129
 130                         ssl = new MonoBtlsSsl (ctx);
 131
 132                         bio = new MonoBtlsBioMono (this);
 133                         ssl.SetBio (bio);
 134
 135                         if (IsServer) {
 136                                 SetPrivateCertificate (nativeServerCertificate);
 137                         } else {
 138                                 ssl.SetServerName (ServerName);
 139                         }
 140                 }
 141
 142                 void SetPrivateCertificate (X509CertificateImplBtls privateCert)
 143                 {
 144                         Debug ("SetPrivateCertificate: {0}", privateCert);
 145                         ssl.SetCertificate (privateCert.X509);
 146                         ssl.SetPrivateKey (privateCert.NativePrivateKey);
 147                         var intermediate = privateCert.IntermediateCertificates;
 148                         if (intermediate == null)
 149                                 return;
 150                         for (int i = 0; i < intermediate.Count; i++) {
 151                                 var impl = (X509CertificateImplBtls)intermediate [i];
 152                                 Debug ("SetPrivateCertificate - add intermediate: {0}", impl);
 153                                 ssl.AddIntermediateCertificate (impl.X509);
 154                         }
 155                 }
 156
 157                 static Exception GetException (MonoBtlsSslError status)
 158                 {
 159                         string file;
 160                         int line;
 161                         var error = MonoBtlsError.GetError (out file, out line);
 162                         if (error == null)
 163                                 return new MonoBtlsException (status);
 164
 165                         var text = MonoBtlsError.GetErrorString (error);
 166
 167                         string message;
 168                         if (file != null)
 169                                 message = string.Format ("{0} {1}\n  at {2}:{3}", status, text, file, line);
 170                         else
 171                                 message = string.Format ("{0} {1}", status, text);
 172                         return new MonoBtlsException (message);
 173                 }
 174
 175                 public override bool ProcessHandshake ()
 176                 {
 177                         var done = false;
 178                         while (!done) {
 179                                 Debug ("ProcessHandshake");
 180                                 MonoBtlsError.ClearError ();
 181                                 var status = DoProcessHandshake ();
 182                                 Debug ("ProcessHandshake #1: {0}", status);
 183
 184                                 switch (status) {
 185                                 case MonoBtlsSslError.None:
 186                                         if (connected)
 187                                                 done = true;
 188                                         else
 189                                                 connected = true;
 190                                         break;
 191                                 case MonoBtlsSslError.WantRead:
 192                                 case MonoBtlsSslError.WantWrite:
 193                                         return false;
 194                                 default:
 195                                         throw GetException (status);
 196                                 }
 197                         }
 198
 199                         ssl.PrintErrors ();
 200
 201                         return true;
 202                 }
 203
 204                 MonoBtlsSslError DoProcessHandshake ()
 205                 {
 206                         if (connected)
 207                                 return ssl.Handshake ();
 208                         else if (IsServer)
 209                                 return ssl.Accept ();
 210                         else
 211                                 return ssl.Connect ();
 212                 }
 213
 214                 public override void FinishHandshake ()
 215                 {
 216                         InitializeSession ();
 217
 218                         isAuthenticated = true;
 219                 }
 220
 221                 void SetupCertificateStore ()
 222                 {
 223                         MonoBtlsProvider.SetupCertificateStore (ctx.CertificateStore);
 224
 225                         if (Settings != null && Settings.TrustAnchors != null) {
 226                                 var trust = IsServer ? MonoBtlsX509TrustKind.TRUST_CLIENT : MonoBtlsX509TrustKind.TRUST_SERVER;
 227                                 ctx.CertificateStore.AddCollection (Settings.TrustAnchors, trust);
 228                         }
 229                 }
 230
 231                 void InitializeConnection ()
 232                 {
 233                         ctx = new MonoBtlsSslCtx ();
 234
 235 #if MARTIN_DEBUG
 236                         errbio = MonoBtlsBio.CreateMonoStream (Console.OpenStandardError ());
 237                         ctx.SetDebugBio (errbio);
 238 #endif
 239
 240                         SetupCertificateStore ();
 241
 242                         if (!IsServer || AskForClientCertificate)
 243                                 ctx.SetVerifyCallback (VerifyCallback, false);
 244                         if (!IsServer)
 245                                 ctx.SetSelectCallback (SelectCallback);
 246
 247                         ctx.SetVerifyParam (MonoBtlsProvider.GetVerifyParam (ServerName, IsServer));
 248
 249                         TlsProtocolCode minProtocol, maxProtocol;
 250                         GetProtocolVersions (out minProtocol, out maxProtocol);
 251
 252                         ctx.SetMinVersion ((int)minProtocol);
 253                         ctx.SetMaxVersion ((int)maxProtocol);
 254
 255                         if (Settings != null && Settings.EnabledCiphers != null) {
 256                                 var ciphers = new short [Settings.EnabledCiphers.Length];
 257                                 for (int i = 0; i < ciphers.Length; i++)
 258                                         ciphers [i] = (short)Settings.EnabledCiphers [i];
 259                                 ctx.SetCiphers (ciphers, true);
 260                         }
 261                 }
 262
 263                 void GetPeerCertificate ()
 264                 {
 265                         if (remoteCertificate != null)
 266                                 return;
 267                         using (var remoteCert = ssl.GetPeerCertificate ()) {
 268                                 if (remoteCert != null)
 269                                         remoteCertificate = MonoBtlsProvider.CreateCertificate (remoteCert);
 270                         }
 271                 }
 272
 273                 void InitializeSession ()
 274                 {
 275                         GetPeerCertificate ();
 276
 277                         if (IsServer && AskForClientCertificate && !certificateValidated) {
 278                                 if (!ValidateCertificate (null, null))
 279                                         throw new TlsException (AlertDescription.CertificateUnknown);
 280                         }
 281
 282                         var cipher = (CipherSuiteCode)ssl.GetCipher ();
 283                         var protocol = (TlsProtocolCode)ssl.GetVersion ();
 284                         var serverName = ssl.GetServerName ();
 285                         Debug ("GET CONNECTION INFO: {0:x}:{0} {1:x}:{1} {2}", cipher, protocol, (TlsProtocolCode)protocol);
 286
 287                         connectionInfo = new MonoTlsConnectionInfo {
 288                                 CipherSuiteCode = cipher,
 289                                 ProtocolVersion = GetProtocol (protocol),
 290                                 PeerDomainName = serverName
 291                         };
 292                 }
 293
 294                 static TlsProtocols GetProtocol (TlsProtocolCode protocol)
 295                 {
 296                         switch (protocol) {
 297                         case TlsProtocolCode.Tls10:
 298                                 return TlsProtocols.Tls10;
 299                         case TlsProtocolCode.Tls11:
 300                                 return TlsProtocols.Tls11;
 301                         case TlsProtocolCode.Tls12:
 302                                 return TlsProtocols.Tls12;
 303                         default:
 304                                 throw new NotSupportedException ();
 305                         }
 306                 }
 307
 308                 public override void Flush ()
 309                 {
 310                         throw new NotImplementedException ();
 311                 }
 312
 313                 public override int Read (byte[] buffer, int offset, int size, out bool wantMore)
 314                 {
 315                         Debug ("Read: {0} {1} {2}", buffer.Length, offset, size);
 316
 317                         var data = Marshal.AllocHGlobal (size);
 318                         if (data == IntPtr.Zero)
 319                                 throw new OutOfMemoryException ();
 320
 321                         try {
 322                                 MonoBtlsError.ClearError ();
 323                                 var status = ssl.Read (data, ref size);
 324                                 Debug ("Read done: {0} {1}", status, size);
 325
 326                                 if (status == MonoBtlsSslError.WantRead) {
 327                                         wantMore = true;
 328                                         return 0;
 329                                 } else if (status != MonoBtlsSslError.None) {
 330                                         throw GetException (status);
 331                                 }
 332
 333                                 if (size > 0)
 334                                         Marshal.Copy (data, buffer, offset, size);
 335
 336                                 wantMore = false;
 337                                 return size;
 338                         } finally {
 339                                 Marshal.FreeHGlobal (data);
 340                         }
 341                 }
 342
 343                 public override int Write (byte[] buffer, int offset, int size, out bool wantMore)
 344                 {
 345                         Debug ("Write: {0} {1} {2}", buffer.Length, offset, size);
 346
 347                         var data = Marshal.AllocHGlobal (size);
 348                         if (data == IntPtr.Zero)
 349                                 throw new OutOfMemoryException ();
 350
 351                         try {
 352                                 MonoBtlsError.ClearError ();
 353                                 Marshal.Copy (buffer, offset, data, size);
 354                                 var status = ssl.Write (data, ref size);
 355                                 Debug ("Write done: {0} {1}", status, size);
 356
 357                                 if (status == MonoBtlsSslError.WantWrite) {
 358                                         wantMore = true;
 359                                         return 0;
 360                                 } else if (status != MonoBtlsSslError.None) {
 361                                         throw GetException (status);
 362                                 }
 363
 364                                 wantMore = false;
 365                                 return size;
 366                         } finally {
 367                                 Marshal.FreeHGlobal (data);
 368                         }
 369                 }
 370
 371                 public override void Close ()
 372                 {
 373                         Debug ("Close!");
 374
 375                         if (ssl != null) {
 376                                 ssl.Dispose ();
 377                                 ssl = null;
 378                         }
 379                         if (ctx != null) {
 380                                 ctx.Dispose ();
 381                                 ctx = null;
 382                         }
 383                         if (bio != null) {
 384                                 bio.Dispose ();
 385                                 bio = null;
 386                         }
 387                         if (errbio != null) {
 388                                 errbio.Dispose ();
 389                                 errbio = null;
 390                         }
 391                 }
 392
 393                 void Dispose<T> (ref T disposable)
 394                         where T : class, IDisposable
 395                 {
 396                         try {
 397                                 if (disposable != null)
 398                                         disposable.Dispose ();
 399                         } catch {
 400                                 ;
 401                         } finally {
 402                                 disposable = null;
 403                         }
 404                 }
 405
 406                 protected override void Dispose (bool disposing)
 407                 {
 408                         try {
 409                                 if (disposing) {
 410                                         Dispose (ref remoteCertificate);
 411                                         Dispose (ref nativeServerCertificate);
 412                                         Dispose (ref nativeClientCertificate);
 413                                         Dispose (ref clientCertificate);
 414                                         Dispose (ref ctx);
 415                                         Dispose (ref ssl);
 416                                         Dispose (ref bio);
 417                                         Dispose (ref errbio);
 418                                 }
 419                         } finally {
 420                                 base.Dispose (disposing);
 421                         }
 422                 }
 423
 424                 int IMonoBtlsBioMono.Read (byte[] buffer, int offset, int size, out bool wantMore)
 425                 {
 426                         Debug ("InternalRead: {0} {1}", offset, size);
 427                         var ret = Parent.InternalRead (buffer, offset, size, out wantMore);
 428                         Debug ("InternalReadDone: {0} {1}", ret, wantMore);
 429                         return ret;
 430                 }
 431
 432                 bool IMonoBtlsBioMono.Write (byte[] buffer, int offset, int size)
 433                 {
 434                         Debug ("InternalWrite: {0} {1}", offset, size);
 435                         var ret = Parent.InternalWrite (buffer, offset, size);
 436                         Debug ("InternalWrite done: {0}", ret);
 437                         return ret;
 438                 }
 439
 440                 void IMonoBtlsBioMono.Flush ()
 441                 {
 442                         ;
 443                 }
 444
 445                 void IMonoBtlsBioMono.Close ()
 446                 {
 447                         ;
 448                 }
 449
 450                 public override bool HasContext {
 451                         get { return ssl != null && ssl.IsValid; }
 452                 }
 453                 public override bool IsAuthenticated {
 454                         get { return isAuthenticated; }
 455                 }
 456                 public override MonoTlsConnectionInfo ConnectionInfo {
 457                         get { return connectionInfo; }
 458                 }
 459                 internal override bool IsRemoteCertificateAvailable {
 460                         get { return remoteCertificate != null; }
 461                 }
 462                 internal override X509Certificate LocalClientCertificate {
 463                         get { return clientCertificate; }
 464                 }
 465                 public override X509Certificate RemoteCertificate {
 466                         get { return remoteCertificate; }
 467                 }
 468                 public override TlsProtocols NegotiatedProtocol {
 469                         get { return connectionInfo.ProtocolVersion; }
 470                 }
 471         }
 472 }
 473 #endif