mcs/class/corlib/Mono.Security.X509/X509Extension.cs

   1 //
   2 // X509Extension.cs: Base class for all X.509 extensions.
   3 //
   4 // Author:
   5 //      Sebastien Pouliot  <sebastien@ximian.com>
   6 //
   7 // (C) 2003 Motus Technologies Inc. (http://www.motus.com)
   8 // (C) 2004 Novell (http://www.novell.com)
   9 //
  10
  11 //
  12 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
  13 //
  14 // Permission is hereby granted, free of charge, to any person obtaining
  15 // a copy of this software and associated documentation files (the
  16 // "Software"), to deal in the Software without restriction, including
  17 // without limitation the rights to use, copy, modify, merge, publish,
  18 // distribute, sublicense, and/or sell copies of the Software, and to
  19 // permit persons to whom the Software is furnished to do so, subject to
  20 // the following conditions:
  21 //
  22 // The above copyright notice and this permission notice shall be
  23 // included in all copies or substantial portions of the Software.
  24 //
  25 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  26 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  27 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  28 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  29 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  30 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  31 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  32 //
  33
  34 using System;
  35 using System.Globalization;
  36 using System.Text;
  37
  38 using Mono.Security;
  39
  40 namespace Mono.Security.X509 {
  41         /*
  42          * Extension  ::=  SEQUENCE  {
  43          *      extnID      OBJECT IDENTIFIER,
  44          *      critical    BOOLEAN DEFAULT FALSE,
  45          *      extnValue   OCTET STRING
  46          * }
  47          */
  48 #if INSIDE_CORLIB
  49         internal
  50 #else
  51         public
  52 #endif
  53         class X509Extension {
  54
  55                 protected string extnOid;
  56                 protected bool extnCritical;
  57                 protected ASN1 extnValue;
  58
  59                 internal X509Extension ()
  60                 {
  61                         extnCritical = false;
  62                 }
  63
  64                 public X509Extension (ASN1 asn1)
  65                 {
  66                         if ((asn1.Tag != 0x30) || (asn1.Count < 2))
  67                                 throw new ArgumentException ("Invalid X.509 extension");
  68                         if (asn1[0].Tag != 0x06)
  69                                 throw new ArgumentException ("Invalid X.509 extension");
  70                         extnOid = ASN1Convert.ToOid (asn1 [0]);
  71                         extnCritical = ((asn1[1].Tag == 0x01) && (asn1[1].Value[0] == 0xFF));
  72                         extnValue = asn1 [asn1.Count - 1]; // last element
  73                         Decode ();
  74                 }
  75
  76                 public X509Extension (X509Extension extension) : this ()
  77                 {
  78                         if (extension == null)
  79                                 throw new ArgumentNullException ("extension");
  80                         if ((extension.Value.Tag != 0x04) || (extension.Value.Count != 0))
  81                                 throw new ArgumentException ("Invalid extension");
  82                         extnOid = extension.Oid;
  83                         extnCritical = extension.Critical;
  84                         extnValue = extension.Value;
  85                         Decode ();
  86                 }
  87
  88                 protected virtual void Decode ()
  89                 {
  90                 }
  91
  92                 protected virtual void Encode ()
  93                 {
  94                 }
  95
  96                 public ASN1 ASN1 {
  97                         get {
  98                                 ASN1 extension = new ASN1 (0x30);
  99                                 extension.Add (ASN1Convert.FromOid (extnOid));
 100                                 if (extnCritical)
 101                                         extension.Add (new ASN1 (0x01, new byte [1] { 0x01 }));
 102                                 ASN1 os = extension.Add (new ASN1 (0x04));
 103                                 Encode ();
 104                                 os.Add (extnValue);
 105                                 return extension;
 106                         }
 107                 }
 108
 109                 public string Oid {
 110                         get { return extnOid; }
 111                 }
 112
 113                 public bool Critical {
 114                         get { return extnCritical; }
 115                 }
 116
 117                 // this gets overrided with more meaningful names
 118                 public virtual string Name {
 119                         get { return extnOid; }
 120                 }
 121
 122                 public ASN1 Value {
 123                         get { return extnValue; }
 124                 }
 125
 126                 public override bool Equals (object obj)
 127                 {
 128                         if (obj == null)
 129                                 return false;
 130
 131                         X509Extension ex = (obj as X509Extension);
 132                         if (ex == null)
 133                                 return false;
 134
 135                         if (extnCritical != ex.extnCritical)
 136                                 return false;
 137                         if (extnOid != ex.extnOid)
 138                                 return false;
 139                         if (extnValue.Length != ex.extnValue.Length)
 140                                 return false;
 141
 142                         for (int i=0; i < extnValue.Length; i++) {
 143                                 if (extnValue [i] != ex.extnValue [i])
 144                                         return false;
 145                         }
 146                         return true;
 147                 }
 148
 149                 public byte[] GetBytes ()
 150                 {
 151                         return ASN1.GetBytes ();
 152                 }
 153
 154                 public override int GetHashCode ()
 155                 {
 156                         // OID should be unique in a collection of extensions
 157                         return extnOid.GetHashCode ();
 158                 }
 159
 160                 private void WriteLine (StringBuilder sb, int n, int pos)
 161                 {
 162                         byte[] value = extnValue.Value;
 163                         int p = pos;
 164                         StringBuilder preview = new StringBuilder ();
 165                         for (int j=0; j < 8; j++) {
 166                                 if (j < n) {
 167                                         sb.Append (value [p++].ToString ("X2", CultureInfo.InvariantCulture));
 168                                         sb.Append (" ");
 169                                 }
 170                                 else
 171                                         sb.Append ("   ");
 172                         }
 173                         sb.Append ("  ");
 174                         p = pos;
 175                         for (int j=0; j < n; j++) {
 176                                 byte b = value [p++];
 177                                 if (b < 0x20)
 178                                         sb.Append (".");
 179                                 else
 180                                         sb.Append (Convert.ToChar (b));
 181                         }
 182                         sb.Append (Environment.NewLine);
 183                 }
 184
 185                 public override string ToString ()
 186                 {
 187                         StringBuilder sb = new StringBuilder ();
 188                         int div = (extnValue.Length >> 3);
 189                         int rem = (extnValue.Length - (div << 3));
 190                         int x = 0;
 191                         for (int i=0; i < div; i++) {
 192                                 WriteLine (sb, 8, x);
 193                                 x += 8;
 194                         }
 195                         WriteLine (sb, rem, x);
 196                         return sb.ToString ();
 197                 }
 198         }
 199 }