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.ByteArrayOutputStream;
  42: import java.io.InputStream;
  43: import java.io.IOException;
  44: import java.io.OutputStream;
  45: import java.io.PrintWriter;
  46: import java.io.StringWriter;
  47: 
  48: import java.nio.ByteBuffer;
  49: import java.nio.ByteOrder;
  50: 
  51: /**
  52:  * An SSL nonce.
  53:  *
  54:  * <pre>
  55: struct
  56: {
  57:   uint32 gmt_unix_time;
  58:   opaque random_bytes[28];
  59: } Random;
  60:  */
  61: public class Random implements Builder, Constructed
  62: {
  63: 
  64:   // Fields.
  65:   // -------------------------------------------------------------------------
  66: 
  67:   static final int RANDOM_LENGTH = 28;
  68: 
  69:   private final ByteBuffer buffer;
  70: 
  71:   // Constructors.
  72:   // -------------------------------------------------------------------------
  73: 
  74:   public Random (final ByteBuffer buffer)
  75:   {
  76:     this.buffer = buffer.duplicate().order(ByteOrder.BIG_ENDIAN);
  77:   }
  78: 
  79:   public Random copy()
  80:   {
  81:     ByteBuffer buffer = ByteBuffer.allocate(32);
  82:     buffer.put((ByteBuffer) this.buffer.duplicate().position(0));
  83:     return new Random(buffer);
  84:   }
  85: 
  86:   public int length()
  87:   {
  88:     return RANDOM_LENGTH + 4;
  89:   }
  90:   
  91:   public ByteBuffer buffer()
  92:   {
  93:     return ((ByteBuffer) buffer.duplicate().position(0).limit(length())).slice();
  94:   }
  95: 
  96:   public int gmtUnixTime ()
  97:   {
  98:     return buffer.getInt(0);
  99:   }
 100: 
 101:   public byte[] randomBytes()
 102:   {
 103:     byte[] buf = new byte[28];
 104:     buffer.position (4);
 105:     buffer.get (buf);
 106:     return buf;
 107:   }
 108: 
 109:   public void setGmtUnixTime (final int gmtUnixTime)
 110:   {
 111:     buffer.putInt (0, gmtUnixTime);
 112:   }
 113: 
 114:   public void setRandomBytes (final byte[] randomBytes)
 115:   {
 116:     setRandomBytes (randomBytes, 0);
 117:   }
 118: 
 119:   public void setRandomBytes (final byte[] randomBytes, final int offset)
 120:   {
 121:     if (randomBytes.length - offset < RANDOM_LENGTH)
 122:       throw new IllegalArgumentException ("random value too short");
 123:     buffer.position (4);
 124:     buffer.put (randomBytes, offset, RANDOM_LENGTH);
 125:   }
 126: 
 127:   public String toString (final String prefix)
 128:   {
 129:     StringWriter str = new StringWriter();
 130:     PrintWriter out = new PrintWriter(str);
 131:     if (prefix != null)
 132:       out.print (prefix);
 133:     out.println("struct {");
 134:     if (prefix != null)
 135:       out.print (prefix);
 136:     out.print ("  gmt_unix_time: ");
 137:     out.print (gmtUnixTime ());
 138:     out.println (";");
 139:     if (prefix != null)
 140:       out.print (prefix);
 141:     out.print ("  random_bytes:  ");
 142:     out.print (Util.toHexString (randomBytes (), ':'));
 143:     out.println (";");
 144:     if (prefix != null)
 145:       out.print (prefix);
 146:     out.print ("} Random;");
 147:     return str.toString();
 148:   }
 149: 
 150:   public String toString ()
 151:   {
 152:     return toString (null);
 153:   }
 154: }