mcs/class/System/System.Security.Cryptography.X509Certificates/X509Certificate2.cs

   1 //
   2 // System.Security.Cryptography.X509Certificate2 class
   3 //
   4 // Author:
   5 //      Sebastien Pouliot  <sebastien@ximian.com>
   6 //
   7 // (C) 2003 Motus Technologies Inc. (http://www.motus.com)
   8 // Copyright (C) 2004-2006 Novell Inc. (http://www.novell.com)
   9 //
  10 // Permission is hereby granted, free of charge, to any person obtaining
  11 // a copy of this software and associated documentation files (the
  12 // "Software"), to deal in the Software without restriction, including
  13 // without limitation the rights to use, copy, modify, merge, publish,
  14 // distribute, sublicense, and/or sell copies of the Software, and to
  15 // permit persons to whom the Software is furnished to do so, subject to
  16 // the following conditions:
  17 //
  18 // The above copyright notice and this permission notice shall be
  19 // included in all copies or substantial portions of the Software.
  20 //
  21 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  22 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  23 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  24 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  25 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  26 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  27 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  28 //
  29
  30 #if SECURITY_DEP
  31
  32 #if MONOTOUCH || MONODROID
  33 using Mono.Security;
  34 using Mono.Security.Cryptography;
  35 using MX = Mono.Security.X509;
  36 #else
  37 extern alias MonoSecurity;
  38
  39 using MonoSecurity::Mono.Security;
  40 using MonoSecurity::Mono.Security.Cryptography;
  41 using MX = MonoSecurity::Mono.Security.X509;
  42 #endif
  43
  44 #endif
  45
  46 using System.IO;
  47 using System.Text;
  48
  49 namespace System.Security.Cryptography.X509Certificates {
  50
  51         [Serializable]
  52         public class X509Certificate2 : X509Certificate {
  53 #if !SECURITY_DEP
  54                 // Used in Mono.Security HttpsClientStream
  55                 public X509Certificate2 (byte[] rawData)
  56                 {
  57                 }
  58 #endif
  59 #if SECURITY_DEP
  60                 private bool _archived;
  61                 private X509ExtensionCollection _extensions;
  62                 private string _name = String.Empty;
  63                 private string _serial;
  64                 private PublicKey _publicKey;
  65                 private X500DistinguishedName issuer_name;
  66                 private X500DistinguishedName subject_name;
  67                 private Oid signature_algorithm;
  68
  69                 private MX.X509Certificate _cert;
  70
  71                 private static string empty_error = Locale.GetText ("Certificate instance is empty.");
  72
  73                 // constructors
  74
  75                 public X509Certificate2 ()
  76                 {
  77                         _cert = null;
  78                 }
  79
  80                 public X509Certificate2 (byte[] rawData)
  81                 {
  82                         Import (rawData, (string)null, X509KeyStorageFlags.DefaultKeySet);
  83                 }
  84
  85                 public X509Certificate2 (byte[] rawData, string password)
  86                 {
  87                         Import (rawData, password, X509KeyStorageFlags.DefaultKeySet);
  88                 }
  89
  90                 public X509Certificate2 (byte[] rawData, SecureString password)
  91                 {
  92                         Import (rawData, password, X509KeyStorageFlags.DefaultKeySet);
  93                 }
  94
  95                 public X509Certificate2 (byte[] rawData, string password, X509KeyStorageFlags keyStorageFlags)
  96                 {
  97                         Import (rawData, password, keyStorageFlags);
  98                 }
  99
 100                 public X509Certificate2 (byte[] rawData, SecureString password, X509KeyStorageFlags keyStorageFlags)
 101                 {
 102                         Import (rawData, password, keyStorageFlags);
 103                 }
 104
 105                 public X509Certificate2 (string fileName)
 106                 {
 107                         Import (fileName, String.Empty, X509KeyStorageFlags.DefaultKeySet);
 108                 }
 109
 110                 public X509Certificate2 (string fileName, string password)
 111                 {
 112                         Import (fileName, password, X509KeyStorageFlags.DefaultKeySet);
 113                 }
 114
 115                 public X509Certificate2 (string fileName, SecureString password)
 116                 {
 117                         Import (fileName, password, X509KeyStorageFlags.DefaultKeySet);
 118                 }
 119
 120                 public X509Certificate2 (string fileName, string password, X509KeyStorageFlags keyStorageFlags)
 121                 {
 122                         Import (fileName, password, keyStorageFlags);
 123                 }
 124
 125                 public X509Certificate2 (string fileName, SecureString password, X509KeyStorageFlags keyStorageFlags)
 126                 {
 127                         Import (fileName, password, keyStorageFlags);
 128                 }
 129
 130                 public X509Certificate2 (IntPtr handle) : base (handle)
 131                 {
 132                         _cert = new MX.X509Certificate (base.GetRawCertData ());
 133                 }
 134
 135                 public X509Certificate2 (X509Certificate certificate)
 136                         : base (certificate)
 137                 {
 138                         _cert = new MX.X509Certificate (base.GetRawCertData ());
 139                 }
 140
 141                 // properties
 142
 143                 public bool Archived {
 144                         get {
 145                                 if (_cert == null)
 146                                         throw new CryptographicException (empty_error);
 147                                 return _archived;
 148                         }
 149                         set {
 150                                 if (_cert == null)
 151                                         throw new CryptographicException (empty_error);
 152                                 _archived = value;
 153                         }
 154                 }
 155
 156                 public X509ExtensionCollection Extensions {
 157                         get {
 158                                 if (_cert == null)
 159                                         throw new CryptographicException (empty_error);
 160                                 if (_extensions == null)
 161                                         _extensions = new X509ExtensionCollection (_cert);
 162                                 return _extensions;
 163                         }
 164                 }
 165
 166                 public string FriendlyName {
 167                         get {
 168                                 if (_cert == null)
 169                                         throw new CryptographicException (empty_error);
 170                                 return _name;
 171                         }
 172                         set {
 173                                 if (_cert == null)
 174                                         throw new CryptographicException (empty_error);
 175                                 _name = value;
 176                         }
 177                 }
 178
 179                 // FIXME - Could be more efficient
 180                 public bool HasPrivateKey {
 181                         get { return PrivateKey != null; }
 182                 }
 183
 184                 public X500DistinguishedName IssuerName {
 185                         get {
 186                                 if (_cert == null)
 187                                         throw new CryptographicException (empty_error);
 188                                 if (issuer_name == null)
 189                                         issuer_name = new X500DistinguishedName (_cert.GetIssuerName ().GetBytes ());
 190                                 return issuer_name;
 191                         }
 192                 }
 193
 194                 public DateTime NotAfter {
 195                         get {
 196                                 if (_cert == null)
 197                                         throw new CryptographicException (empty_error);
 198                                 return _cert.ValidUntil.ToLocalTime ();
 199                         }
 200                 }
 201
 202                 public DateTime NotBefore {
 203                         get {
 204                                 if (_cert == null)
 205                                         throw new CryptographicException (empty_error);
 206                                 return _cert.ValidFrom.ToLocalTime ();
 207                         }
 208                 }
 209
 210                 public AsymmetricAlgorithm PrivateKey {
 211                         get {
 212                                 if (_cert == null)
 213                                         throw new CryptographicException (empty_error);
 214                                 try {
 215                                         if (_cert.RSA != null) {
 216                                                 RSACryptoServiceProvider rcsp = _cert.RSA as RSACryptoServiceProvider;
 217                                                 if (rcsp != null)
 218                                                         return rcsp.PublicOnly ? null : rcsp;
 219
 220                                                 RSAManaged rsam = _cert.RSA as RSAManaged;
 221                                                 if (rsam != null)
 222                                                         return rsam.PublicOnly ? null : rsam;
 223
 224                                                 _cert.RSA.ExportParameters (true);
 225                                                 return _cert.RSA;
 226                                         } else if (_cert.DSA != null) {
 227                                                 DSACryptoServiceProvider dcsp = _cert.DSA as DSACryptoServiceProvider;
 228                                                 if (dcsp != null)
 229                                                         return dcsp.PublicOnly ? null : dcsp;
 230
 231                                                 _cert.DSA.ExportParameters (true);
 232                                                 return _cert.DSA;
 233                                         }
 234                                 }
 235                                 catch {
 236                                 }
 237                                 return null;
 238                         }
 239                         set {
 240                                 if (_cert == null)
 241                                         throw new CryptographicException (empty_error);
 242
 243                                 // allow NULL so we can "forget" the key associated to the certificate
 244                                 // e.g. in case we want to export it in another format (see bug #396620)
 245                                 if (value == null) {
 246                                         _cert.RSA = null;
 247                                         _cert.DSA = null;
 248                                 } else  if (value is RSA)
 249                                         _cert.RSA = (RSA) value;
 250                                 else if (value is DSA)
 251                                         _cert.DSA = (DSA) value;
 252                                 else
 253                                         throw new NotSupportedException ();
 254                         }
 255                 }
 256
 257                 public PublicKey PublicKey {
 258                         get {
 259                                 if (_cert == null)
 260                                         throw new CryptographicException (empty_error);
 261
 262                                 if (_publicKey == null) {
 263                                         try {
 264                                                 _publicKey = new PublicKey (_cert);
 265                                         }
 266                                         catch (Exception e) {
 267                                                 string msg = Locale.GetText ("Unable to decode public key.");
 268                                                 throw new CryptographicException (msg, e);
 269                                         }
 270                                 }
 271                                 return _publicKey;
 272                         }
 273                 }
 274
 275                 public byte[] RawData {
 276                         get {
 277                                 if (_cert == null)
 278                                         throw new CryptographicException (empty_error);
 279
 280                                 return base.GetRawCertData ();
 281                         }
 282                 }
 283
 284                 public string SerialNumber {
 285                         get {
 286                                 if (_cert == null)
 287                                         throw new CryptographicException (empty_error);
 288
 289                                 if (_serial == null) {
 290                                         StringBuilder sb = new StringBuilder ();
 291                                         byte[] serial = _cert.SerialNumber;
 292                                         for (int i=serial.Length - 1; i >= 0; i--)
 293                                                 sb.Append (serial [i].ToString ("X2"));
 294                                         _serial = sb.ToString ();
 295                                 }
 296                                 return _serial;
 297                         }
 298                 }
 299
 300                 public Oid SignatureAlgorithm {
 301                         get {
 302                                 if (_cert == null)
 303                                         throw new CryptographicException (empty_error);
 304
 305                                 if (signature_algorithm == null)
 306                                         signature_algorithm = new Oid (_cert.SignatureAlgorithm);
 307                                 return signature_algorithm;
 308                         }
 309                 }
 310
 311                 public X500DistinguishedName SubjectName {
 312                         get {
 313                                 if (_cert == null)
 314                                         throw new CryptographicException (empty_error);
 315
 316                                 if (subject_name == null)
 317                                         subject_name = new X500DistinguishedName (_cert.GetSubjectName ().GetBytes ());
 318                                 return subject_name;
 319                         }
 320                 }
 321
 322                 public string Thumbprint {
 323                         get { return base.GetCertHashString (); }
 324                 }
 325
 326                 public int Version {
 327                         get {
 328                                 if (_cert == null)
 329                                         throw new CryptographicException (empty_error);
 330                                 return _cert.Version;
 331                         }
 332                 }
 333
 334                 // methods
 335
 336                 [MonoTODO ("always return String.Empty for UpnName, DnsFromAlternativeName and UrlName")]
 337                 public string GetNameInfo (X509NameType nameType, bool forIssuer)
 338                 {
 339                         switch (nameType) {
 340                         case X509NameType.SimpleName:
 341                                 if (_cert == null)
 342                                         throw new CryptographicException (empty_error);
 343                                 // return CN= or, if missing, the first part of the DN
 344                                 ASN1 sn = forIssuer ? _cert.GetIssuerName () : _cert.GetSubjectName ();
 345                                 ASN1 dn = Find (commonName, sn);
 346                                 if (dn != null)
 347                                         return GetValueAsString (dn);
 348                                 if (sn.Count == 0)
 349                                         return String.Empty;
 350                                 ASN1 last_entry = sn [sn.Count - 1];
 351                                 if (last_entry.Count == 0)
 352                                         return String.Empty;
 353                                 return GetValueAsString (last_entry [0]);
 354                         case X509NameType.EmailName:
 355                                 // return the E= part of the DN (if present)
 356                                 ASN1 e = Find (email, forIssuer ? _cert.GetIssuerName () : _cert.GetSubjectName ());
 357                                 if (e != null)
 358                                         return GetValueAsString (e);
 359                                 return String.Empty;
 360                         case X509NameType.UpnName:
 361                                 // FIXME - must find/create test case
 362                                 return String.Empty;
 363                         case X509NameType.DnsName:
 364                                 // return the CN= part of the DN (if present)
 365                                 ASN1 cn = Find (commonName, forIssuer ? _cert.GetIssuerName () : _cert.GetSubjectName ());
 366                                 if (cn != null)
 367                                         return GetValueAsString (cn);
 368                                 return String.Empty;
 369                         case X509NameType.DnsFromAlternativeName:
 370                                 // FIXME - must find/create test case
 371                                 return String.Empty;
 372                         case X509NameType.UrlName:
 373                                 // FIXME - must find/create test case
 374                                 return String.Empty;
 375                         default:
 376                                 throw new ArgumentException ("nameType");
 377                         }
 378                 }
 379
 380                 static byte[] commonName = { 0x55, 0x04, 0x03 };
 381                 static byte[] email = { 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x09, 0x01 };
 382
 383                 private ASN1 Find (byte[] oid, ASN1 dn)
 384                 {
 385                         if (dn.Count == 0)
 386                                 return null;
 387
 388                         // process SET
 389                         for (int i = 0; i < dn.Count; i++) {
 390                                 ASN1 set = dn [i];
 391                                 for (int j = 0; j < set.Count; j++) {
 392                                         ASN1 pair = set [j];
 393                                         if (pair.Count != 2)
 394                                                 continue;
 395
 396                                         ASN1 poid = pair [0];
 397                                         if (poid == null)
 398                                                 continue;
 399
 400                                         if (poid.CompareValue (oid))
 401                                                 return pair;
 402                                 }
 403                         }
 404                         return null;
 405                 }
 406
 407                 private string GetValueAsString (ASN1 pair)
 408                 {
 409                         if (pair.Count != 2)
 410                                 return String.Empty;
 411
 412                         ASN1 value = pair [1];
 413                         if ((value.Value == null) || (value.Length == 0))
 414                                 return String.Empty;
 415
 416                         if (value.Tag == 0x1E) {
 417                                 // BMPSTRING
 418                                 StringBuilder sb = new StringBuilder ();
 419                                 for (int j = 1; j < value.Value.Length; j += 2)
 420                                         sb.Append ((char)value.Value [j]);
 421                                 return sb.ToString ();
 422                         } else {
 423                                 return Encoding.UTF8.GetString (value.Value);
 424                         }
 425                 }
 426
 427                 private MX.X509Certificate ImportPkcs12 (byte[] rawData, string password)
 428                 {
 429                         MX.PKCS12 pfx = null;
 430                         if (string.IsNullOrEmpty (password)) {
 431                                 try {
 432                                         // Support both unencrypted PKCS#12..
 433                                         pfx = new MX.PKCS12 (rawData, (string)null);
 434                                 } catch {
 435                                         // ..and PKCS#12 encrypted with an empty password
 436                                         pfx = new MX.PKCS12 (rawData, string.Empty);
 437                                 }
 438                         } else {
 439                                 pfx = new MX.PKCS12 (rawData, password);
 440                         }
 441
 442                         if (pfx.Certificates.Count == 0) {
 443                                 // no certificate was found
 444                                 return null;
 445                         } else if (pfx.Keys.Count == 0) {
 446                                 // no key were found - pick the first certificate
 447                                 return pfx.Certificates [0];
 448                         } else {
 449                                 // find the certificate that match the first key
 450                                 MX.X509Certificate cert = null;
 451                                 var keypair = (pfx.Keys [0] as AsymmetricAlgorithm);
 452                                 string pubkey = keypair.ToXmlString (false);
 453                                 foreach (var c in pfx.Certificates) {
 454                                         if (((c.RSA != null) && (pubkey == c.RSA.ToXmlString (false))) ||
 455                                                 ((c.DSA != null) && (pubkey == c.DSA.ToXmlString (false)))) {
 456                                                 cert = c;
 457                                                 break;
 458                                         }
 459                                 }
 460                                 if (cert == null) {
 461                                         cert = pfx.Certificates [0]; // no match, pick first certificate without keys
 462                                 } else {
 463                                         cert.RSA = (keypair as RSA);
 464                                         cert.DSA = (keypair as DSA);
 465                                 }
 466                                 return cert;
 467                         }
 468                 }
 469
 470                 public override void Import (byte[] rawData)
 471                 {
 472                         Import (rawData, (string)null, X509KeyStorageFlags.DefaultKeySet);
 473                 }
 474
 475                 [MonoTODO ("missing KeyStorageFlags support")]
 476                 public override void Import (byte[] rawData, string password, X509KeyStorageFlags keyStorageFlags)
 477                 {
 478                         MX.X509Certificate cert = null;
 479                         if (password == null) {
 480                                 try {
 481                                         cert = new MX.X509Certificate (rawData);
 482                                 }
 483                                 catch (Exception e) {
 484                                         try {
 485                                                 cert = ImportPkcs12 (rawData, null);
 486                                         }
 487                                         catch {
 488                                                 string msg = Locale.GetText ("Unable to decode certificate.");
 489                                                 // inner exception is the original (not second) exception
 490                                                 throw new CryptographicException (msg, e);
 491                                         }
 492                                 }
 493                         } else {
 494                                 // try PKCS#12
 495                                 try {
 496                                         cert = ImportPkcs12 (rawData, password);
 497                                 }
 498                                 catch {
 499                                         // it's possible to supply a (unrequired/unusued) password
 500                                         // fix bug #79028
 501                                         cert = new MX.X509Certificate (rawData);
 502                                 }
 503                         }
 504                         // we do not have to fully re-decode the certificate since X509Certificate does not deal with keys
 505                         if (cert != null) {
 506                                 base.Import (cert.RawData, (string) null, keyStorageFlags);
 507                                 _cert = cert; // becuase base call will call Reset!
 508                         }
 509                 }
 510
 511                 [MonoTODO ("SecureString is incomplete")]
 512                 public override void Import (byte[] rawData, SecureString password, X509KeyStorageFlags keyStorageFlags)
 513                 {
 514                         Import (rawData, (string) null, keyStorageFlags);
 515                 }
 516
 517                 public override void Import (string fileName)
 518                 {
 519                         byte[] rawData = File.ReadAllBytes (fileName);
 520                         Import (rawData, (string)null, X509KeyStorageFlags.DefaultKeySet);
 521                 }
 522
 523                 [MonoTODO ("missing KeyStorageFlags support")]
 524                 public override void Import (string fileName, string password, X509KeyStorageFlags keyStorageFlags)
 525                 {
 526                         byte[] rawData = File.ReadAllBytes (fileName);
 527                         Import (rawData, password, keyStorageFlags);
 528                 }
 529
 530                 [MonoTODO ("SecureString is incomplete")]
 531                 public override void Import (string fileName, SecureString password, X509KeyStorageFlags keyStorageFlags)
 532                 {
 533                         byte[] rawData = File.ReadAllBytes (fileName);
 534                         Import (rawData, (string)null, keyStorageFlags);
 535                 }
 536
 537                 public override void Reset ()
 538                 {
 539                         _cert = null;
 540                         _archived = false;
 541                         _extensions = null;
 542                         _name = String.Empty;
 543                         _serial = null;
 544                         _publicKey = null;
 545                         issuer_name = null;
 546                         subject_name = null;
 547                         signature_algorithm = null;
 548                         base.Reset ();
 549                 }
 550
 551                 public override string ToString ()
 552                 {
 553                         if (_cert == null)
 554                                 return "System.Security.Cryptography.X509Certificates.X509Certificate2";
 555
 556                         return base.ToString (true);
 557                 }
 558
 559                 public override string ToString (bool verbose)
 560                 {
 561                         if (_cert == null)
 562                                 return "System.Security.Cryptography.X509Certificates.X509Certificate2";
 563
 564                         // the non-verbose X509Certificate2 == verbose X509Certificate
 565                         if (!verbose)
 566                                 return base.ToString (true);
 567
 568                         string nl = Environment.NewLine;
 569                         StringBuilder sb = new StringBuilder ();
 570                         sb.AppendFormat ("[Version]{0}  V{1}{0}{0}", nl, Version);
 571                         sb.AppendFormat ("[Subject]{0}  {1}{0}{0}", nl, Subject);
 572                         sb.AppendFormat ("[Issuer]{0}  {1}{0}{0}", nl, Issuer);
 573                         sb.AppendFormat ("[Serial Number]{0}  {1}{0}{0}", nl, SerialNumber);
 574                         sb.AppendFormat ("[Not Before]{0}  {1}{0}{0}", nl, NotBefore);
 575                         sb.AppendFormat ("[Not After]{0}  {1}{0}{0}", nl, NotAfter);
 576                         sb.AppendFormat ("[Thumbprint]{0}  {1}{0}{0}", nl, Thumbprint);
 577                         sb.AppendFormat ("[Signature Algorithm]{0}  {1}({2}){0}{0}", nl, SignatureAlgorithm.FriendlyName,
 578                                 SignatureAlgorithm.Value);
 579
 580                         AsymmetricAlgorithm key = PublicKey.Key;
 581                         sb.AppendFormat ("[Public Key]{0}  Algorithm: ", nl);
 582                         if (key is RSA)
 583                                 sb.Append ("RSA");
 584                         else if (key is DSA)
 585                                 sb.Append ("DSA");
 586                         else
 587                                 sb.Append (key.ToString ());
 588                         sb.AppendFormat ("{0}  Length: {1}{0}  Key Blob: ", nl, key.KeySize);
 589                         AppendBuffer (sb, PublicKey.EncodedKeyValue.RawData);
 590                         sb.AppendFormat ("{0}  Parameters: ", nl);
 591                         AppendBuffer (sb, PublicKey.EncodedParameters.RawData);
 592                         sb.Append (nl);
 593
 594                         return sb.ToString ();
 595                 }
 596
 597                 private static void AppendBuffer (StringBuilder sb, byte[] buffer)
 598                 {
 599                         if (buffer == null)
 600                                 return;
 601                         for (int i=0; i < buffer.Length; i++) {
 602                                 sb.Append (buffer [i].ToString ("x2"));
 603                                 if (i < buffer.Length - 1)
 604                                         sb.Append (" ");
 605                         }
 606                 }
 607
 608                 [MonoTODO ("by default this depends on the incomplete X509Chain")]
 609                 public bool Verify ()
 610                 {
 611                         if (_cert == null)
 612                                 throw new CryptographicException (empty_error);
 613
 614                         X509Chain chain = X509Chain.Create ();
 615                         if (!chain.Build (this))
 616                                 return false;
 617                         // TODO - check chain and other stuff ???
 618                         return true;
 619                 }
 620
 621                 // static methods
 622
 623                 private static byte[] signedData = new byte[] { 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x07, 0x02 };
 624
 625                 [MonoTODO ("Detection limited to Cert, Pfx, Pkcs12, Pkcs7 and Unknown")]
 626                 public static X509ContentType GetCertContentType (byte[] rawData)
 627                 {
 628                         if ((rawData == null) || (rawData.Length == 0))
 629                                 throw new ArgumentException ("rawData");
 630
 631                         X509ContentType type = X509ContentType.Unknown;
 632                         try {
 633                                 ASN1 data = new ASN1 (rawData);
 634                                 if (data.Tag != 0x30) {
 635                                         string msg = Locale.GetText ("Unable to decode certificate.");
 636                                         throw new CryptographicException (msg);
 637                                 }
 638
 639                                 if (data.Count == 0)
 640                                         return type;
 641
 642                                 if (data.Count == 3) {
 643                                         switch (data [0].Tag) {
 644                                         case 0x30:
 645                                                 // SEQUENCE / SEQUENCE / BITSTRING
 646                                                 if ((data [1].Tag == 0x30) && (data [2].Tag == 0x03))
 647                                                         type = X509ContentType.Cert;
 648                                                 break;
 649                                         case 0x02:
 650                                                 // INTEGER / SEQUENCE / SEQUENCE
 651                                                 if ((data [1].Tag == 0x30) && (data [2].Tag == 0x30))
 652                                                         type = X509ContentType.Pkcs12;
 653                                                 // note: Pfx == Pkcs12
 654                                                 break;
 655                                         }
 656                                 }
 657                                 // check for PKCS#7 (count unknown but greater than 0)
 658                                 // SEQUENCE / OID (signedData)
 659                                 if ((data [0].Tag == 0x06) && data [0].CompareValue (signedData))
 660                                         type = X509ContentType.Pkcs7;
 661                         }
 662                         catch (Exception e) {
 663                                 string msg = Locale.GetText ("Unable to decode certificate.");
 664                                 throw new CryptographicException (msg, e);
 665                         }
 666
 667                         return type;
 668                 }
 669
 670                 [MonoTODO ("Detection limited to Cert, Pfx, Pkcs12 and Unknown")]
 671                 public static X509ContentType GetCertContentType (string fileName)
 672                 {
 673                         if (fileName == null)
 674                                 throw new ArgumentNullException ("fileName");
 675                         if (fileName.Length == 0)
 676                                 throw new ArgumentException ("fileName");
 677
 678                         byte[] data = File.ReadAllBytes (fileName);
 679                         return GetCertContentType (data);
 680                 }
 681
 682                 // internal stuff because X509Certificate2 isn't complete enough
 683                 // (maybe X509Certificate3 will be better?)
 684
 685                 internal MX.X509Certificate MonoCertificate {
 686                         get { return _cert; }
 687                 }
 688
 689 #else
 690                 // HACK - this ensure the type X509Certificate2 and PrivateKey property exists in the build before
 691                 // Mono.Security.dll is built. This is required to get working client certificate in SSL/TLS
 692                 public AsymmetricAlgorithm PrivateKey {
 693                         get { return null; }
 694                 }
 695 #endif
 696         }
 697 }