src/org/bouncycastle/asn1/x509/SubjectPublicKeyInfo.java

   1 package org.bouncycastle.asn1.x509;
   2
   3 import java.io.*;
   4 import java.util.Enumeration;
   5
   6 import org.bouncycastle.asn1.*;
   7
   8 /**
   9  * The object that contains the public key stored in a certficate.
  10  * <p>
  11  * The getEncoded() method in the public keys in the JCE produces a DER
  12  * encoded one of these.
  13  */
  14 public class SubjectPublicKeyInfo
  15     implements DEREncodable
  16 {
  17     private AlgorithmIdentifier     algId;
  18     private DERBitString            keyData;
  19
  20     public static SubjectPublicKeyInfo getInstance(
  21         ASN1TaggedObject obj,
  22         boolean          explicit)
  23     {
  24         return getInstance(ASN1Sequence.getInstance(obj, explicit));
  25     }
  26
  27     public static SubjectPublicKeyInfo getInstance(
  28         Object  obj)
  29     {
  30         if (obj instanceof SubjectPublicKeyInfo)
  31         {
  32             return (SubjectPublicKeyInfo)obj;
  33         }
  34         else if (obj instanceof ASN1Sequence)
  35         {
  36             return new SubjectPublicKeyInfo((ASN1Sequence)obj);
  37         }
  38
  39         throw new IllegalArgumentException("unknown object in factory");
  40     }
  41
  42     public SubjectPublicKeyInfo(
  43         AlgorithmIdentifier algId,
  44         DEREncodable        publicKey)
  45     {
  46         this.keyData = new DERBitString(publicKey);
  47         this.algId = algId;
  48     }
  49
  50     public SubjectPublicKeyInfo(
  51         AlgorithmIdentifier algId,
  52         byte[]              publicKey)
  53     {
  54         this.keyData = new DERBitString(publicKey);
  55         this.algId = algId;
  56     }
  57
  58     public SubjectPublicKeyInfo(
  59         ASN1Sequence  seq)
  60     {
  61         Enumeration         e = seq.getObjects();
  62
  63         this.algId = AlgorithmIdentifier.getInstance(e.nextElement());
  64         this.keyData = (DERBitString)e.nextElement();
  65     }
  66
  67     public AlgorithmIdentifier getAlgorithmId()
  68     {
  69         return algId;
  70     }
  71
  72     /**
  73      * for when the public key is an encoded object - if the bitstring
  74      * can't be decoded this routine throws an IOException.
  75      *
  76      * @exception IOException - if the bit string doesn't represent a DER
  77      * encoded object.
  78      */
  79     public DERObject getPublicKey()
  80         throws IOException
  81     {
  82         ByteArrayInputStream    bIn = new ByteArrayInputStream(keyData.getBytes());
  83         DERInputStream          dIn = new DERInputStream(bIn);
  84
  85         return dIn.readObject();
  86     }
  87
  88     /**
  89      * for when the public key is raw bits...
  90      */
  91     public DERBitString getPublicKeyData()
  92     {
  93         return keyData;
  94     }
  95
  96     /**
  97      * <pre>
  98      * SubjectPublicKeyInfo ::= SEQUENCE {
  99      *                          algorithm AlgorithmIdentifier,
 100      *                          publicKey BIT STRING }
 101      * </pre>
 102      */
 103     public DERObject getDERObject()
 104     {
 105         DERConstructedSequence  seq = new DERConstructedSequence();
 106
 107         seq.addObject(algId);
 108         seq.addObject(keyData);
 109
 110         return seq;
 111     }
 112 }