class/Mono.Security/Mono.Security.X509.Extensions/NetscapeCertTypeExtension.cs

   1 //
   2 // NetscapeCertTypeExtension.cs: Handles Netscape CertType extensions.
   3 //
   4 // Author:
   5 //      Sebastien Pouliot  <sebastien@ximian.com>
   6 //
   7 // (C) 2004 Novell (http://www.novell.com)
   8 //
   9
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining
  12 // a copy of this software and associated documentation files (the
  13 // "Software"), to deal in the Software without restriction, including
  14 // without limitation the rights to use, copy, modify, merge, publish,
  15 // distribute, sublicense, and/or sell copies of the Software, and to
  16 // permit persons to whom the Software is furnished to do so, subject to
  17 // the following conditions:
  18 //
  19 // The above copyright notice and this permission notice shall be
  20 // included in all copies or substantial portions of the Software.
  21 //
  22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29 //
  30
  31 using System;
  32 using System.Globalization;
  33 using System.Text;
  34
  35 using Mono.Security;
  36 using Mono.Security.X509;
  37
  38 namespace Mono.Security.X509.Extensions {
  39
  40         // References:
  41         // a.   Netscape Certificate Extensions Navigator 3.0 Version
  42         //      http://wp.netscape.com/eng/security/cert-exts.html
  43         // b.   Netscape Certificate Extensions Communicator 4.0 Version
  44         //      http://wp.netscape.com/eng/security/comm4-cert-exts.html
  45         // c.   2.16.840.1.113730.1.1 - Netscape certificate type
  46         //      http://www.alvestrand.no/objectid/2.16.840.1.113730.1.1.html
  47
  48         public class NetscapeCertTypeExtension : X509Extension {
  49
  50                 /*
  51                  * bit-0 SSL client - this cert is certified for SSL client authentication use
  52                  * bit-1 SSL server - this cert is certified for SSL server authentication use
  53                  * bit-2 S/MIME - this cert is certified for use by clients(New in PR3)
  54                  * bit-3 Object Signing - this cert is certified for signing objects such as Java applets and plugins(New in PR3)
  55                  * bit-4 Reserved - this bit is reserved for future use
  56                  * bit-5 SSL CA - this cert is certified for issuing certs for SSL use
  57                  * bit-6 S/MIME CA - this cert is certified for issuing certs for S/MIME use(New in PR3)
  58                  * bit-7 Object Signing CA - this cert is certified for issuing certs for Object Signing(New in PR3)
  59                  */
  60
  61                 // note: because nothing is simple in ASN.1 bits are reversed
  62                 [Flags]
  63                 public enum CertTypes {
  64                         SslClient = 0x80,
  65                         SslServer = 0x40,
  66                         Smime = 0x20,
  67                         ObjectSigning = 0x10,
  68                         SslCA = 0x04,
  69                         SmimeCA = 0x02,
  70                         ObjectSigningCA = 0x01
  71                 }
  72
  73                 private int ctbits;
  74
  75                 public NetscapeCertTypeExtension () : base ()
  76                 {
  77                         extnOid = "2.16.840.1.113730.1.1";
  78                 }
  79
  80                 public NetscapeCertTypeExtension (ASN1 asn1) : base (asn1)
  81                 {
  82                 }
  83
  84                 public NetscapeCertTypeExtension (X509Extension extension) : base (extension)
  85                 {
  86                 }
  87
  88                 protected override void Decode ()
  89                 {
  90                         ASN1 bitString = new ASN1 (extnValue.Value);
  91                         if (bitString.Tag != 0x03)
  92                                 throw new ArgumentException ("Invalid NetscapeCertType extension");
  93                         int i = 1; // byte zero has the number of unused bits (ASN1's BITSTRING)
  94                         while (i < bitString.Value.Length)
  95                                 ctbits = (ctbits << 8) + bitString.Value [i++];
  96                 }
  97
  98                 public override string Name {
  99                         get { return "NetscapeCertType"; }
 100                 }
 101
 102 /*              public CertType Type {
 103                         get { return ctbits; }
 104                         set { ctbits = value; }
 105                 }*/
 106
 107                 public bool Support (CertTypes usage)
 108                 {
 109                         int x = Convert.ToInt32 (usage, CultureInfo.InvariantCulture);
 110                         return ((x & ctbits) == x);
 111                 }
 112
 113                 public override string ToString ()
 114                 {
 115                         const string separator = " , ";
 116                         StringBuilder sb = new StringBuilder ();
 117                         if (Support (CertTypes.SslClient))
 118                                 sb.Append ("SSL Client Authentication");
 119                         if (Support (CertTypes.SslServer)) {
 120                                 if (sb.Length > 0)
 121                                         sb.Append (separator);
 122                                 sb.Append ("SSL Server Authentication");
 123                         }
 124                         if (Support (CertTypes.Smime)) {
 125                                 if (sb.Length > 0)
 126                                         sb.Append (separator);
 127                                 sb.Append ("SMIME");
 128                         }
 129                         if (Support (CertTypes.ObjectSigning)) {
 130                                 if (sb.Length > 0)
 131                                         sb.Append (separator);
 132                                 sb.Append ("Object Signing");
 133                         }
 134                         if (Support (CertTypes.SslCA)) {
 135                                 if (sb.Length > 0)
 136                                         sb.Append (separator);
 137                                 sb.Append ("SSL CA");
 138                         }
 139                         if (Support (CertTypes.SmimeCA)) {
 140                                 if (sb.Length > 0)
 141                                         sb.Append (separator);
 142                                 sb.Append ("SMIME CA");
 143                         }
 144                         if (Support (CertTypes.ObjectSigningCA)) {
 145                                 if (sb.Length > 0)
 146                                         sb.Append (separator);
 147                                 sb.Append ("Object Signing CA");
 148                         }
 149                         sb.Append ("(");
 150                         sb.Append (ctbits.ToString ("X2", CultureInfo.InvariantCulture));
 151                         sb.Append (")");
 152                         sb.Append (Environment.NewLine);
 153                         return sb.ToString ();
 154                 }
 155         }
 156 }