src/org/bouncycastle/asn1/DERObjectIdentifier.java

   1 package org.bouncycastle.asn1;
   2
   3 import java.io.*;
   4
   5 public class DERObjectIdentifier
   6     extends DERObject
   7 {
   8     String      identifier;
   9
  10     /**
  11      * return an OID from the passed in object
  12      *
  13      * @exception IllegalArgumentException if the object cannot be converted.
  14      */
  15     public static DERObjectIdentifier getInstance(
  16         Object  obj)
  17     {
  18         if (obj == null || obj instanceof DERObjectIdentifier)
  19         {
  20             return (DERObjectIdentifier)obj;
  21         }
  22
  23         if (obj instanceof ASN1OctetString)
  24         {
  25             return new DERObjectIdentifier(((ASN1OctetString)obj).getOctets());
  26         }
  27
  28         if (obj instanceof ASN1TaggedObject)
  29         {
  30             return getInstance(((ASN1TaggedObject)obj).getObject());
  31         }
  32
  33         throw new IllegalArgumentException("illegal object in getInstance: " + obj.getClass().getName());
  34     }
  35
  36     /**
  37      * return an Object Identifier from a tagged object.
  38      *
  39      * @param obj the tagged object holding the object we want
  40      * @param explicit true if the object is meant to be explicitly
  41      *              tagged false otherwise.
  42      * @exception IllegalArgumentException if the tagged object cannot
  43      *               be converted.
  44      */
  45     public static DERObjectIdentifier getInstance(
  46         ASN1TaggedObject obj,
  47         boolean          explicit)
  48     {
  49         return getInstance(obj.getObject());
  50     }
  51
  52
  53     DERObjectIdentifier(
  54         byte[]  bytes)
  55     {
  56         int             head = bytes[0] & 0xff;
  57         StringBuffer    objId = new StringBuffer();
  58         int             value = 0;
  59         boolean         first = true;
  60
  61         for (int i = 0; i != bytes.length; i++)
  62         {
  63             int b = bytes[i] & 0xff;
  64
  65             value = value * 128 + (b & 0x7f);
  66             if ((b & 0x80) == 0)             // end of number reached
  67             {
  68                 if (first)
  69                 {
  70                     switch (value / 40)
  71                     {
  72                     case 0:
  73                         objId.append('0');
  74                         break;
  75                     case 1:
  76                         objId.append('1');
  77                         value -= 40;
  78                         break;
  79                     default:
  80                         objId.append('2');
  81                         value -= 80;
  82                     }
  83                     first = false;
  84                 }
  85
  86                 objId.append('.');
  87                 objId.append(Integer.toString(value));
  88                 value = 0;
  89             }
  90         }
  91
  92         this.identifier = objId.toString();
  93     }
  94
  95     public DERObjectIdentifier(
  96         String  identifier)
  97     {
  98         this.identifier = identifier;
  99     }
 100
 101     public String getId()
 102     {
 103         return identifier;
 104     }
 105
 106     private void writeField(
 107         OutputStream    out,
 108         int             fieldValue)
 109         throws IOException
 110     {
 111         if (fieldValue >= (1 << 7))
 112         {
 113             if (fieldValue >= (1 << 14))
 114             {
 115                 if (fieldValue >= (1 << 21))
 116                 {
 117                     if (fieldValue >= (1 << 28))
 118                     {
 119                         out.write((fieldValue >> 28) | 0x80);
 120                     }
 121                     out.write((fieldValue >> 21) | 0x80);
 122                 }
 123                 out.write((fieldValue >> 14) | 0x80);
 124             }
 125             out.write((fieldValue >> 7) | 0x80);
 126         }
 127         out.write(fieldValue & 0x7f);
 128     }
 129
 130     void encode(
 131         DEROutputStream out)
 132         throws IOException
 133     {
 134         OIDTokenizer            tok = new OIDTokenizer(identifier);
 135         ByteArrayOutputStream   bOut = new ByteArrayOutputStream();
 136         DEROutputStream         dOut = new DEROutputStream(bOut);
 137
 138         writeField(bOut,
 139                     Integer.parseInt(tok.nextToken()) * 40
 140                     + Integer.parseInt(tok.nextToken()));
 141
 142         while (tok.hasMoreTokens())
 143         {
 144             writeField(bOut, Integer.parseInt(tok.nextToken()));
 145         }
 146
 147         dOut.close();
 148
 149         byte[]  bytes = bOut.toByteArray();
 150
 151         out.writeEncoded(OBJECT_IDENTIFIER, bytes);
 152     }
 153
 154     public int hashCode()
 155     {
 156         return identifier.hashCode();
 157     }
 158
 159     public boolean equals(
 160         Object  o)
 161     {
 162         if ((o == null) || !(o instanceof DERObjectIdentifier))
 163         {
 164             return false;
 165         }
 166
 167         return identifier.equals(((DERObjectIdentifier)o).identifier);
 168     }
 169 }