mcs/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 using System;
  11 using System.Text;
  12
  13 using Mono.Security;
  14 using Mono.Security.X509;
  15
  16 namespace Mono.Security.X509.Extensions {
  17
  18         // References:
  19         // a.   Netscape Certificate Extensions Navigator 3.0 Version
  20         //      http://wp.netscape.com/eng/security/cert-exts.html
  21         // b.   Netscape Certificate Extensions Communicator 4.0 Version
  22         //      http://wp.netscape.com/eng/security/comm4-cert-exts.html
  23         // c.   2.16.840.1.113730.1.1 - Netscape certificate type
  24         //      http://www.alvestrand.no/objectid/2.16.840.1.113730.1.1.html
  25
  26         public class NetscapeCertTypeExtension : X509Extension {
  27
  28                 /*
  29                  * bit-0 SSL client - this cert is certified for SSL client authentication use
  30                  * bit-1 SSL server - this cert is certified for SSL server authentication use
  31                  * bit-2 S/MIME - this cert is certified for use by clients(New in PR3)
  32                  * bit-3 Object Signing - this cert is certified for signing objects such as Java applets and plugins(New in PR3)
  33                  * bit-4 Reserved - this bit is reserved for future use
  34                  * bit-5 SSL CA - this cert is certified for issuing certs for SSL use
  35                  * bit-6 S/MIME CA - this cert is certified for issuing certs for S/MIME use(New in PR3)
  36                  * bit-7 Object Signing CA - this cert is certified for issuing certs for Object Signing(New in PR3)
  37                  */
  38
  39                 // note: because nothing is simple in ASN.1 bits are reversed
  40                 [Flags]
  41                 public enum CertType {
  42                         SslClient = 0x80,
  43                         SslServer = 0x40,
  44                         Smime = 0x20,
  45                         ObjectSigning = 0x10,
  46                         SslCa = 0x04,
  47                         SmimeCa = 0x02,
  48                         ObjectSigningCA = 0x01
  49                 }
  50
  51                 private int ctbits;
  52
  53                 public NetscapeCertTypeExtension () : base ()
  54                 {
  55                         extnOid = "2.16.840.1.113730.1.1";
  56                 }
  57
  58                 public NetscapeCertTypeExtension (ASN1 asn1) : base (asn1) {}
  59
  60                 public NetscapeCertTypeExtension (X509Extension extension) : base (extension) {}
  61
  62                 protected override void Decode ()
  63                 {
  64                         ASN1 bitString = new ASN1 (extnValue.Value);
  65                         if (bitString.Tag != 0x03)
  66                                 throw new ArgumentException ("Invalid NetscapeCertType extension");
  67                         int i = 1; // byte zero has the number of unused bits (ASN1's BITSTRING)
  68                         while (i < bitString.Value.Length)
  69                                 ctbits = (ctbits << 8) + bitString.Value [i++];
  70                 }
  71
  72                 public override string Name {
  73                         get { return "NetscapeCertType"; }
  74                 }
  75
  76 /*              public CertType Type {
  77                         get { return ctbits; }
  78                         set { ctbits = value; }
  79                 }*/
  80
  81                 public bool Support (CertType usage)
  82                 {
  83                         int x = Convert.ToInt32 (usage);
  84                         return ((x & ctbits) == x);
  85                 }
  86
  87                 public override string ToString ()
  88                 {
  89                         const string separator = " , ";
  90                         StringBuilder sb = new StringBuilder ();
  91                         if (Support (CertType.SslClient))
  92                                 sb.Append ("SSL Client Authentication");
  93                         if (Support (CertType.SslServer)) {
  94                                 if (sb.Length > 0)
  95                                         sb.Append (separator);
  96                                 sb.Append ("SSL Server Authentication");
  97                         }
  98                         if (Support (CertType.Smime)) {
  99                                 if (sb.Length > 0)
 100                                         sb.Append (separator);
 101                                 sb.Append ("SMIME");
 102                         }
 103                         if (Support (CertType.ObjectSigning)) {
 104                                 if (sb.Length > 0)
 105                                         sb.Append (separator);
 106                                 sb.Append ("Object Signing");
 107                         }
 108                         if (Support (CertType.SslCa)) {
 109                                 if (sb.Length > 0)
 110                                         sb.Append (separator);
 111                                 sb.Append ("SSL CA");
 112                         }
 113                         if (Support (CertType.SmimeCa)) {
 114                                 if (sb.Length > 0)
 115                                         sb.Append (separator);
 116                                 sb.Append ("SMIME CA");
 117                         }
 118                         if (Support (CertType.ObjectSigningCA)) {
 119                                 if (sb.Length > 0)
 120                                         sb.Append (separator);
 121                                 sb.Append ("Object Signing CA");
 122                         }
 123                         sb.Append ("(");
 124                         sb.Append (ctbits.ToString ("X2"));
 125                         sb.Append (")");
 126                         sb.Append (Environment.NewLine);
 127                         return sb.ToString ();
 128                 }
 129         }
 130 }