libjava/classpath/gnu/javax/net/ssl/provider/Random.java

   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 }