Source for gnu.java.security.x509.ext.GeneralSubtree

   1: /* GeneralSubtree.java --
   2:    Copyright (C) 2006  Free Software Foundation, Inc.
   3: 
   4: This file is a 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 of the License, or (at
   9: your option) 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; if not, write to the Free Software
  18: Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301
  19: 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.x509.ext;
  40: 
  41: import gnu.java.security.der.DERReader;
  42: import gnu.java.security.der.DERValue;
  43: 
  44: import java.io.IOException;
  45: import java.math.BigInteger;
  46: 
  47: /**
  48:  * The GeneralSubtree structure, a part of the {@link NameConstraints}
  49:  * extension.
  50:  *
  51:  * <pre>
  52:   GeneralSubtree ::= SEQUENCE {
  53:     base                    GeneralName,
  54:     minimum         [0]     BaseDistance DEFAULT 0,
  55:     maximum         [1]     BaseDistance OPTIONAL }
  56: 
  57:   BaseDistance ::= INTEGER (0..MAX)</pre>
  58:  *
  59:  * @author Casey Marshall (csm@gnu.org)
  60:  */
  61: public class GeneralSubtree
  62: {
  63:   private final GeneralName base;
  64:   private final int minimum;
  65:   private final int maximum;
  66: 
  67:   public GeneralSubtree(byte[] encoded) throws IOException
  68:   {
  69:     DERReader reader = new DERReader(encoded);
  70:     DERValue generalSubtree = reader.read();
  71: 
  72:     if (!generalSubtree.isConstructed())
  73:       throw new IOException("malformed GeneralSubtree");
  74: 
  75:     DERValue generalName = reader.read();
  76:     base = new GeneralName(generalName.getEncoded());
  77:     if (generalName.isConstructed())
  78:       reader.skip(generalName.getLength());
  79: 
  80:     int len = generalName.getEncodedLength();
  81:     if (len < generalSubtree.getLength())
  82:       {
  83:         DERValue distance = reader.read();
  84:         if (distance.getTag() == 0)
  85:           {
  86:             minimum = ((BigInteger) distance.getValue()).intValue();
  87:             len += distance.getEncodedLength();
  88:             if (len < generalSubtree.getLength())
  89:               {
  90:                 distance = reader.read();
  91:                 if (distance.getTag() != 1)
  92:                   throw new IOException("unexpected tag "
  93:                                         + distance.getTag() +
  94:                                         " (expected 1 for GeneralSubtree maximum distance)");
  95:                 maximum = ((BigInteger) distance.getValue()).intValue();
  96:               }
  97:             else
  98:               {
  99:                 maximum = -1;
 100:               }
 101:           }
 102:         else if (distance.getTag() == 1)
 103:           {
 104:             minimum = 1;
 105:             maximum = ((BigInteger) distance.getValue()).intValue();
 106:           }
 107:         else
 108:           {
 109:             throw new IOException("unexpected tag " + distance.getTag()
 110:                                   + " (expected 0 or 1 for GeneralSubtree distance)");
 111:           }
 112:       }
 113:     else
 114:       {
 115:         minimum = 0;
 116:         maximum = -1;
 117:       }
 118:   }
 119: 
 120:   /**
 121:    * Returns the base name.
 122:    *
 123:    * @return The base name.
 124:    */
 125:   public GeneralName base()
 126:   {
 127:     return base;
 128:   }
 129: 
 130:   /**
 131:    * Returns the minimum base distance, possibly zero.
 132:    *
 133:    * @return The minimum base distance.
 134:    */
 135:   public int minimum()
 136:   {
 137:     return minimum;
 138:   }
 139: 
 140:   /**
 141:    * Returns the maximum base distance, or -1 if this value was not specified.
 142:    *
 143:    * @return The maximum base distance.
 144:    */
 145:   public int maximum()
 146:   {
 147:     return maximum;
 148:   }
 149: 
 150:   public String toString()
 151:   {
 152:     return (GeneralSubtree.class.getName() + " [ base=" + base
 153:             + "; minimum=" + minimum + "; maximim=" + maximum
 154:             + " ]");
 155:   }
 156: }