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                         var error = MonoBtlsError.GetError ();
 160                         var text = MonoBtlsError.GetErrorString (error);
 161                         return new MonoBtlsException ("{0} {1}", status, text);
 162                 }
 163
 164                 public override bool ProcessHandshake ()
 165                 {
 166                         var done = false;
 167                         while (!done) {
 168                                 Debug ("ProcessHandshake");
 169                                 MonoBtlsError.ClearError ();
 170                                 var status = DoProcessHandshake ();
 171                                 Debug ("ProcessHandshake #1: {0}", status);
 172
 173                                 switch (status) {
 174                                 case MonoBtlsSslError.None:
 175                                         if (connected)
 176                                                 done = true;
 177                                         else
 178                                                 connected = true;
 179                                         break;
 180                                 case MonoBtlsSslError.WantRead:
 181                                 case MonoBtlsSslError.WantWrite:
 182                                         return false;
 183                                 default:
 184                                         throw GetException (status);
 185                                 }
 186                         }
 187
 188                         ssl.PrintErrors ();
 189
 190                         return true;
 191                 }
 192
 193                 MonoBtlsSslError DoProcessHandshake ()
 194                 {
 195                         if (connected)
 196                                 return ssl.Handshake ();
 197                         else if (IsServer)
 198                                 return ssl.Accept ();
 199                         else
 200                                 return ssl.Connect ();
 201                 }
 202
 203                 public override void FinishHandshake ()
 204                 {
 205                         InitializeSession ();
 206
 207                         isAuthenticated = true;
 208                 }
 209
 210                 void SetupCertificateStore ()
 211                 {
 212                         MonoBtlsProvider.SetupCertificateStore (ctx.CertificateStore);
 213
 214                         if (Settings != null && Settings.TrustAnchors != null) {
 215                                 var trust = IsServer ? MonoBtlsX509TrustKind.TRUST_CLIENT : MonoBtlsX509TrustKind.TRUST_SERVER;
 216                                 ctx.CertificateStore.AddCollection (Settings.TrustAnchors, trust);
 217                         }
 218                 }
 219
 220                 void InitializeConnection ()
 221                 {
 222                         ctx = new MonoBtlsSslCtx ();
 223
 224 #if MARTIN_DEBUG
 225                         errbio = MonoBtlsBio.CreateMonoStream (Console.OpenStandardError ());
 226                         ctx.SetDebugBio (errbio);
 227 #endif
 228
 229                         SetupCertificateStore ();
 230
 231                         if (!IsServer || AskForClientCertificate)
 232                                 ctx.SetVerifyCallback (VerifyCallback, false);
 233                         if (!IsServer)
 234                                 ctx.SetSelectCallback (SelectCallback);
 235
 236                         ctx.SetVerifyParam (MonoBtlsProvider.GetVerifyParam (ServerName, IsServer));
 237
 238                         TlsProtocolCode minProtocol, maxProtocol;
 239                         GetProtocolVersions (out minProtocol, out maxProtocol);
 240
 241                         ctx.SetMinVersion ((int)minProtocol);
 242                         ctx.SetMaxVersion ((int)maxProtocol);
 243
 244                         if (Settings != null && Settings.EnabledCiphers != null) {
 245                                 var ciphers = new short [Settings.EnabledCiphers.Length];
 246                                 for (int i = 0; i < ciphers.Length; i++)
 247                                         ciphers [i] = (short)Settings.EnabledCiphers [i];
 248                                 ctx.SetCiphers (ciphers, true);
 249                         }
 250                 }
 251
 252                 void GetPeerCertificate ()
 253                 {
 254                         if (remoteCertificate != null)
 255                                 return;
 256                         using (var remoteCert = ssl.GetPeerCertificate ()) {
 257                                 if (remoteCert != null)
 258                                         remoteCertificate = MonoBtlsProvider.CreateCertificate (remoteCert);
 259                         }
 260                 }
 261
 262                 void InitializeSession ()
 263                 {
 264                         GetPeerCertificate ();
 265
 266                         if (IsServer && AskForClientCertificate && !certificateValidated) {
 267                                 if (!ValidateCertificate (null, null))
 268                                         throw new TlsException (AlertDescription.CertificateUnknown);
 269                         }
 270
 271                         var cipher = (CipherSuiteCode)ssl.GetCipher ();
 272                         var protocol = (TlsProtocolCode)ssl.GetVersion ();
 273                         Debug ("GET CONNECTION INFO: {0:x}:{0} {1:x}:{1} {2}", cipher, protocol, (TlsProtocolCode)protocol);
 274
 275                         connectionInfo = new MonoTlsConnectionInfo {
 276                                 CipherSuiteCode = cipher,
 277                                 ProtocolVersion = GetProtocol (protocol)
 278                         };
 279                 }
 280
 281                 static TlsProtocols GetProtocol (TlsProtocolCode protocol)
 282                 {
 283                         switch (protocol) {
 284                         case TlsProtocolCode.Tls10:
 285                                 return TlsProtocols.Tls10;
 286                         case TlsProtocolCode.Tls11:
 287                                 return TlsProtocols.Tls11;
 288                         case TlsProtocolCode.Tls12:
 289                                 return TlsProtocols.Tls12;
 290                         default:
 291                                 throw new NotSupportedException ();
 292                         }
 293                 }
 294
 295                 public override void Flush ()
 296                 {
 297                         throw new NotImplementedException ();
 298                 }
 299
 300                 public override int Read (byte[] buffer, int offset, int size, out bool wantMore)
 301                 {
 302                         Debug ("Read: {0} {1} {2}", buffer.Length, offset, size);
 303
 304                         var data = Marshal.AllocHGlobal (size);
 305                         if (data == IntPtr.Zero)
 306                                 throw new OutOfMemoryException ();
 307
 308                         try {
 309                                 MonoBtlsError.ClearError ();
 310                                 var status = ssl.Read (data, ref size);
 311                                 Debug ("Read done: {0} {1}", status, size);
 312
 313                                 if (status == MonoBtlsSslError.WantRead) {
 314                                         wantMore = true;
 315                                         return 0;
 316                                 } else if (status != MonoBtlsSslError.None) {
 317                                         throw GetException (status);
 318                                 }
 319
 320                                 if (size > 0)
 321                                         Marshal.Copy (data, buffer, offset, size);
 322
 323                                 wantMore = false;
 324                                 return size;
 325                         } finally {
 326                                 Marshal.FreeHGlobal (data);
 327                         }
 328                 }
 329
 330                 public override int Write (byte[] buffer, int offset, int size, out bool wantMore)
 331                 {
 332                         Debug ("Write: {0} {1} {2}", buffer.Length, offset, size);
 333
 334                         var data = Marshal.AllocHGlobal (size);
 335                         if (data == IntPtr.Zero)
 336                                 throw new OutOfMemoryException ();
 337
 338                         try {
 339                                 MonoBtlsError.ClearError ();
 340                                 Marshal.Copy (buffer, offset, data, size);
 341                                 var status = ssl.Write (data, ref size);
 342                                 Debug ("Write done: {0} {1}", status, size);
 343
 344                                 if (status == MonoBtlsSslError.WantWrite) {
 345                                         wantMore = true;
 346                                         return 0;
 347                                 } else if (status != MonoBtlsSslError.None) {
 348                                         throw GetException (status);
 349                                 }
 350
 351                                 wantMore = false;
 352                                 return size;
 353                         } finally {
 354                                 Marshal.FreeHGlobal (data);
 355                         }
 356                 }
 357
 358                 public override void Close ()
 359                 {
 360                         Debug ("Close!");
 361                         ssl.Dispose ();
 362                 }
 363
 364                 void Dispose<T> (ref T disposable)
 365                         where T : class, IDisposable
 366                 {
 367                         try {
 368                                 if (disposable != null)
 369                                         disposable.Dispose ();
 370                         } catch {
 371                                 ;
 372                         } finally {
 373                                 disposable = null;
 374                         }
 375                 }
 376
 377                 protected override void Dispose (bool disposing)
 378                 {
 379                         try {
 380                                 if (disposing) {
 381                                         Dispose (ref remoteCertificate);
 382                                         Dispose (ref nativeServerCertificate);
 383                                         Dispose (ref nativeClientCertificate);
 384                                         Dispose (ref clientCertificate);
 385                                         Dispose (ref ctx);
 386                                         Dispose (ref ssl);
 387                                         Dispose (ref bio);
 388                                         Dispose (ref errbio);
 389                                 }
 390                         } finally {
 391                                 base.Dispose (disposing);
 392                         }
 393                 }
 394
 395                 int IMonoBtlsBioMono.Read (byte[] buffer, int offset, int size, out bool wantMore)
 396                 {
 397                         Debug ("InternalRead: {0} {1}", offset, size);
 398                         var ret = Parent.InternalRead (buffer, offset, size, out wantMore);
 399                         Debug ("InternalReadDone: {0} {1}", ret, wantMore);
 400                         return ret;
 401                 }
 402
 403                 bool IMonoBtlsBioMono.Write (byte[] buffer, int offset, int size)
 404                 {
 405                         Debug ("InternalWrite: {0} {1}", offset, size);
 406                         var ret = Parent.InternalWrite (buffer, offset, size);
 407                         Debug ("InternalWrite done: {0}", ret);
 408                         return ret;
 409                 }
 410
 411                 void IMonoBtlsBioMono.Flush ()
 412                 {
 413                         ;
 414                 }
 415
 416                 void IMonoBtlsBioMono.Close ()
 417                 {
 418                         ;
 419                 }
 420
 421                 public override bool HasContext {
 422                         get { return ssl != null && ssl.IsValid; }
 423                 }
 424                 public override bool IsAuthenticated {
 425                         get { return isAuthenticated; }
 426                 }
 427                 public override MonoTlsConnectionInfo ConnectionInfo {
 428                         get { return connectionInfo; }
 429                 }
 430                 internal override bool IsRemoteCertificateAvailable {
 431                         get { return remoteCertificate != null; }
 432                 }
 433                 internal override X509Certificate LocalClientCertificate {
 434                         get { return clientCertificate; }
 435                 }
 436                 public override X509Certificate RemoteCertificate {
 437                         get { return remoteCertificate; }
 438                 }
 439                 public override TlsProtocols NegotiatedProtocol {
 440                         get { return connectionInfo.ProtocolVersion; }
 441                 }
 442         }
 443 }
 444 #endif