class/System/System.Security.Cryptography.X509Certificates/X509EnhancedKeyUsageExtension.cs

   1 //
   2 // System.Security.Cryptography.X509EnhancedKeyUsageExtension
   3 //
   4 // Author:
   5 //      Sebastien Pouliot  <sebastien@ximian.com>
   6 //
   7 // Copyright (C) 2005 Novell, Inc (http://www.novell.com)
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining
  10 // a copy of this software and associated documentation files (the
  11 // "Software"), to deal in the Software without restriction, including
  12 // without limitation the rights to use, copy, modify, merge, publish,
  13 // distribute, sublicense, and/or sell copies of the Software, and to
  14 // permit persons to whom the Software is furnished to do so, subject to
  15 // the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be
  18 // included in all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27 //
  28
  29 #if NET_2_0 && SECURITY_DEP
  30
  31 using System.Text;
  32
  33 using Mono.Security;
  34
  35 namespace System.Security.Cryptography.X509Certificates {
  36
  37         public sealed class X509EnhancedKeyUsageExtension : X509Extension {
  38
  39                 internal const string oid = "2.5.29.37";
  40                 internal const string friendlyName = "Enhanced Key Usage";
  41
  42                 private OidCollection _enhKeyUsage;
  43                 private AsnDecodeStatus _status;
  44
  45                 // constructors
  46
  47                 public X509EnhancedKeyUsageExtension ()
  48                 {
  49                         _oid = new Oid (oid, friendlyName);
  50                 }
  51
  52                 public X509EnhancedKeyUsageExtension (AsnEncodedData encodedEnhancedKeyUsages, bool critical)
  53                 {
  54                         // ignore the Oid provided by encodedKeyUsage (our rules!)
  55                         _oid = new Oid (oid, friendlyName);
  56                         _raw = encodedEnhancedKeyUsages.RawData;
  57                         base.Critical = critical;
  58                         _status = Decode (this.RawData);
  59                 }
  60
  61                 public X509EnhancedKeyUsageExtension (OidCollection enhancedKeyUsages, bool critical)
  62                 {
  63                         if (enhancedKeyUsages == null)
  64                                 throw new ArgumentNullException ("enhancedKeyUsages");
  65
  66                         _oid = new Oid (oid, friendlyName);
  67                         base.Critical = critical;
  68                         _enhKeyUsage = enhancedKeyUsages.ReadOnlyCopy ();
  69                         RawData = Encode ();
  70                 }
  71
  72                 // properties
  73
  74                 public OidCollection EnhancedKeyUsages {
  75                         get {
  76                                 switch (_status) {
  77                                 case AsnDecodeStatus.Ok:
  78                                 case AsnDecodeStatus.InformationNotAvailable:
  79                                         if (_enhKeyUsage == null)
  80                                                 _enhKeyUsage = new OidCollection ();
  81                                         _enhKeyUsage.ReadOnly = true;
  82                                         return _enhKeyUsage;
  83                                 default:
  84                                         throw new CryptographicException ("Badly encoded extension.");
  85                                 }
  86                         }
  87                 }
  88
  89                 // methods
  90
  91                 public override void CopyFrom (AsnEncodedData asnEncodedData)
  92                 {
  93                         if (asnEncodedData == null)
  94                                 throw new ArgumentNullException ("encodedData");
  95
  96                         X509Extension ex = (asnEncodedData as X509Extension);
  97                         if (ex == null)
  98                                 throw new ArgumentException (Locale.GetText ("Wrong type."), "asnEncodedData");
  99
 100                         if (ex._oid == null)
 101                                 _oid = new Oid (oid, friendlyName);
 102                         else
 103                                 _oid = new Oid (ex._oid);
 104
 105                         RawData = ex.RawData;
 106                         base.Critical = ex.Critical;
 107                         // and we deal with the rest later
 108                         _status = Decode (this.RawData);
 109                 }
 110
 111                 // internal
 112
 113                 internal AsnDecodeStatus Decode (byte[] extension)
 114                 {
 115                         if ((extension == null) || (extension.Length == 0))
 116                                 return AsnDecodeStatus.BadAsn;
 117                         if (extension [0] != 0x30)
 118                                 return AsnDecodeStatus.BadTag;
 119
 120                         if (_enhKeyUsage == null)
 121                                 _enhKeyUsage = new OidCollection ();
 122
 123                         try {
 124                                 ASN1 ex = new ASN1 (extension);
 125                                 if (ex.Tag != 0x30)
 126                                         throw new CryptographicException (Locale.GetText ("Invalid ASN.1 Tag"));
 127                                 for (int i=0; i < ex.Count; i++) {
 128                                         _enhKeyUsage.Add (new Oid (ASN1Convert.ToOid (ex [i])));
 129                                 }
 130                         }
 131                         catch {
 132                                 return AsnDecodeStatus.BadAsn;
 133                         }
 134
 135                         return AsnDecodeStatus.Ok;
 136                 }
 137
 138                 internal byte[] Encode ()
 139                 {
 140                         ASN1 ex = new ASN1 (0x30);
 141                         foreach (Oid oid in _enhKeyUsage) {
 142                                 ex.Add (ASN1Convert.FromOid (oid.Value));
 143                         }
 144                         return ex.GetBytes ();
 145                 }
 146
 147                 internal override string ToString (bool multiLine)
 148                 {
 149                         switch (_status) {
 150                         case AsnDecodeStatus.BadAsn:
 151                                 return String.Empty;
 152                         case AsnDecodeStatus.BadTag:
 153                         case AsnDecodeStatus.BadLength:
 154                                 return FormatUnkownData (_raw);
 155                         case AsnDecodeStatus.InformationNotAvailable:
 156                                 return "Information Not Available";
 157                         }
 158
 159                         if (_oid.Value != oid)
 160                                 return String.Format ("Unknown Key Usage ({0})", _oid.Value);
 161                         if (_enhKeyUsage.Count == 0)
 162                                 return "Information Not Available";
 163
 164                         StringBuilder sb = new StringBuilder ();
 165
 166                         for (int i=0; i < _enhKeyUsage.Count; i++) {
 167                                 Oid o = _enhKeyUsage [i];
 168                                 switch (o.Value) {
 169                                 case "1.3.6.1.5.5.7.3.1":
 170                                         sb.Append ("Server Authentication (");
 171                                         break;
 172                                 default:
 173                                         sb.Append ("Unknown Key Usage (");
 174                                         break;
 175                                 }
 176                                 sb.Append (o.Value);
 177                                 sb.Append (")");
 178
 179                                 if (multiLine)
 180                                         sb.Append (Environment.NewLine);
 181                                 else if (i != (_enhKeyUsage.Count - 1))
 182                                         sb.Append (", ");
 183                         }
 184
 185                         return sb.ToString ();
 186                 }
 187         }
 188 }
 189
 190 #endif