Source for gnu.java.security.provider.DSAKeyFactory

   1: /* DSAKeyFactory.java -- DSA key factory.
   2:    Copyright (C) 2003 Free Software Foundation, Inc.
   3: 
   4: This file is part of GNU Classpath.
   5: 
   6: GNU Classpath is free software; you can redistribute it and/or modify
   7: it under the terms of the GNU General Public License as published by
   8: the Free Software Foundation; either version 2, or (at your option)
   9: any later version.
  10:  
  11: GNU Classpath is distributed in the hope that it will be useful, but
  12: WITHOUT ANY WARRANTY; without even the implied warranty of
  13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14: General Public License for more details.
  15: 
  16: You should have received a copy of the GNU General Public License
  17: along with GNU Classpath; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 USA.
  20: 
  21: Linking this library statically or dynamically with other modules is
  22: making a combined work based on this library.  Thus, the terms and
  23: conditions of the GNU General Public License cover the whole
  24: combination.
  25: 
  26: As a special exception, the copyright holders of this library give you
  27: permission to link this library with independent modules to produce an
  28: executable, regardless of the license terms of these independent
  29: modules, and to copy and distribute the resulting executable under
  30: terms of your choice, provided that you also meet, for each linked
  31: independent module, the terms and conditions of the license of that
  32: module.  An independent module is a module which is not derived from
  33: or based on this library.  If you modify this library, you may extend
  34: this exception to your version of the library, but you are not
  35: obligated to do so.  If you do not wish to do so, delete this
  36: exception statement from your version. */
  37: 
  38: 
  39: package gnu.java.security.provider;
  40: 
  41: import java.security.InvalidKeyException;
  42: import java.security.Key;
  43: import java.security.KeyFactorySpi;
  44: import java.security.PrivateKey;
  45: import java.security.PublicKey;
  46: import java.security.interfaces.DSAPrivateKey;
  47: import java.security.interfaces.DSAPublicKey;
  48: import java.security.spec.DSAPrivateKeySpec;
  49: import java.security.spec.DSAPublicKeySpec;
  50: import java.security.spec.InvalidKeySpecException;
  51: import java.security.spec.KeySpec;
  52: 
  53: /**
  54:  * DSA key factory.
  55:  *
  56:  * @author Casey Marshall (rsdio@metastatic.org)
  57:  */
  58: public class DSAKeyFactory extends KeyFactorySpi
  59: {
  60: 
  61:   // Constructor.
  62:   // ------------------------------------------------------------------------
  63: 
  64:   public DSAKeyFactory()
  65:   {
  66:     super();
  67:   }
  68: 
  69:   // Instance methods.
  70:   // ------------------------------------------------------------------------
  71: 
  72:   protected PrivateKey engineGeneratePrivate(KeySpec keySpec)
  73:     throws InvalidKeySpecException
  74:   {
  75:     if (!(keySpec instanceof DSAPrivateKeySpec))
  76:       throw new InvalidKeySpecException();
  77:     return new GnuDSAPrivateKey(
  78:       ((DSAPrivateKeySpec) keySpec).getX(),
  79:       ((DSAPrivateKeySpec) keySpec).getP(),
  80:       ((DSAPrivateKeySpec) keySpec).getQ(),
  81:       ((DSAPrivateKeySpec) keySpec).getG());
  82:   }
  83: 
  84:   protected PublicKey engineGeneratePublic(KeySpec keySpec)
  85:     throws InvalidKeySpecException
  86:   {
  87:     if (!(keySpec instanceof DSAPublicKeySpec))
  88:       throw new InvalidKeySpecException();
  89:     return new GnuDSAPublicKey(
  90:       ((DSAPublicKeySpec) keySpec).getY(),
  91:       ((DSAPublicKeySpec) keySpec).getP(),
  92:       ((DSAPublicKeySpec) keySpec).getQ(),
  93:       ((DSAPublicKeySpec) keySpec).getG());
  94:   }
  95: 
  96:   protected KeySpec engineGetKeySpec(Key key, Class keySpec)
  97:     throws InvalidKeySpecException
  98:   {
  99:     if ((key instanceof DSAPublicKey) &&
 100:          keySpec.isAssignableFrom(DSAPublicKeySpec.class))
 101:       {
 102:         return new DSAPublicKeySpec(((DSAPublicKey) key).getY(),
 103:           ((DSAPublicKey) key).getParams().getP(),
 104:           ((DSAPublicKey) key).getParams().getQ(),
 105:           ((DSAPublicKey) key).getParams().getG());
 106:       }
 107:     if ((key instanceof DSAPrivateKey) &&
 108:          keySpec.isAssignableFrom(DSAPrivateKeySpec.class))
 109:       {
 110:         return new DSAPrivateKeySpec(((DSAPrivateKey) key).getX(),
 111:           ((DSAPrivateKey) key).getParams().getP(),
 112:           ((DSAPrivateKey) key).getParams().getQ(),
 113:           ((DSAPrivateKey) key).getParams().getG());
 114:       }
 115:     throw new InvalidKeySpecException();
 116:   }
 117: 
 118:   protected Key engineTranslateKey(Key key) throws InvalidKeyException
 119:   {
 120:     if ((key instanceof GnuDSAPublicKey) || (key instanceof GnuDSAPrivateKey))
 121:       return key;
 122:     if (key instanceof DSAPublicKey)
 123:       return new GnuDSAPublicKey(((DSAPublicKey) key).getY(),
 124:         ((DSAPublicKey) key).getParams().getP(),
 125:         ((DSAPublicKey) key).getParams().getQ(),
 126:         ((DSAPublicKey) key).getParams().getG());
 127:     if (key instanceof DSAPrivateKey)
 128:       return new GnuDSAPrivateKey(((DSAPrivateKey) key).getX(),
 129:         ((DSAPrivateKey) key).getParams().getP(),
 130:         ((DSAPrivateKey) key).getParams().getQ(),
 131:         ((DSAPrivateKey) key).getParams().getG());
 132:     throw new InvalidKeyException();
 133:   } 
 134: }