Source for gnu.javax.net.ssl.provider.Random

   1: /* Random.java -- SSL Random structure.
   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.javax.net.ssl.provider;
  40: 
  41: import java.io.PrintWriter;
  42: import java.io.StringWriter;
  43: 
  44: import java.nio.ByteBuffer;
  45: import java.nio.ByteOrder;
  46: 
  47: /**
  48:  * An SSL nonce.
  49:  *
  50:  * <pre>
  51: struct
  52: {
  53:   uint32 gmt_unix_time;
  54:   opaque random_bytes[28];
  55: } Random;
  56:  */
  57: public class Random implements Builder, Constructed
  58: {
  59: 
  60:   // Fields.
  61:   // -------------------------------------------------------------------------
  62: 
  63:   static final int RANDOM_LENGTH = 28;
  64: 
  65:   private final ByteBuffer buffer;
  66: 
  67:   // Constructors.
  68:   // -------------------------------------------------------------------------
  69: 
  70:   public Random (final ByteBuffer buffer)
  71:   {
  72:     this.buffer = buffer.duplicate().order(ByteOrder.BIG_ENDIAN);
  73:   }
  74: 
  75:   public Random copy()
  76:   {
  77:     ByteBuffer buffer = ByteBuffer.allocate(32);
  78:     buffer.put((ByteBuffer) this.buffer.duplicate().position(0));
  79:     return new Random(buffer);
  80:   }
  81: 
  82:   public int length()
  83:   {
  84:     return RANDOM_LENGTH + 4;
  85:   }
  86: 
  87:   public ByteBuffer buffer()
  88:   {
  89:     return ((ByteBuffer) buffer.duplicate().position(0).limit(length())).slice();
  90:   }
  91: 
  92:   public int gmtUnixTime ()
  93:   {
  94:     return buffer.getInt(0);
  95:   }
  96: 
  97:   public byte[] randomBytes()
  98:   {
  99:     byte[] buf = new byte[28];
 100:     buffer.position (4);
 101:     buffer.get (buf);
 102:     return buf;
 103:   }
 104: 
 105:   public void setGmtUnixTime (final int gmtUnixTime)
 106:   {
 107:     buffer.putInt (0, gmtUnixTime);
 108:   }
 109: 
 110:   public void setRandomBytes (final byte[] randomBytes)
 111:   {
 112:     setRandomBytes (randomBytes, 0);
 113:   }
 114: 
 115:   public void setRandomBytes (final byte[] randomBytes, final int offset)
 116:   {
 117:     if (randomBytes.length - offset < RANDOM_LENGTH)
 118:       throw new IllegalArgumentException ("random value too short");
 119:     buffer.position (4);
 120:     buffer.put (randomBytes, offset, RANDOM_LENGTH);
 121:   }
 122: 
 123:   public String toString (final String prefix)
 124:   {
 125:     StringWriter str = new StringWriter();
 126:     PrintWriter out = new PrintWriter(str);
 127:     if (prefix != null)
 128:       out.print (prefix);
 129:     out.println("struct {");
 130:     if (prefix != null)
 131:       out.print (prefix);
 132:     out.print ("  gmt_unix_time: ");
 133:     out.print (gmtUnixTime ());
 134:     out.println (";");
 135:     if (prefix != null)
 136:       out.print (prefix);
 137:     out.print ("  random_bytes:  ");
 138:     out.print (Util.toHexString (randomBytes (), ':'));
 139:     out.println (";");
 140:     if (prefix != null)
 141:       out.print (prefix);
 142:     out.print ("} Random;");
 143:     return str.toString();
 144:   }
 145: 
 146:   public String toString ()
 147:   {
 148:     return toString (null);
 149:   }
 150: }