1 /*
   2  * Copyright (c) 1996, 2007, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 
  27 package sun.security.ssl;
  28 
  29 import java.io.*;
  30 import java.security.SecureRandom;
  31 
  32 /*
  33  * RandomCookie ... SSL hands standard format random cookies (nonces)
  34  * around.  These know how to encode/decode themselves on SSL streams,
  35  * and can be created and printed.
  36  *
  37  * @author David Brownell
  38  */
  39 final class RandomCookie {
  40 
  41     byte random_bytes[];  // exactly 32 bytes
  42 
  43     RandomCookie(SecureRandom generator) {
  44         long temp = System.currentTimeMillis() / 1000;
  45         int gmt_unix_time;
  46         if (temp < Integer.MAX_VALUE) {
  47             gmt_unix_time = (int) temp;
  48         } else {
  49             gmt_unix_time = Integer.MAX_VALUE;          // Whoops!
  50         }
  51 
  52         random_bytes = new byte[32];
  53         generator.nextBytes(random_bytes);
  54 
  55         random_bytes[0] = (byte)(gmt_unix_time >> 24);
  56         random_bytes[1] = (byte)(gmt_unix_time >> 16);
  57         random_bytes[2] = (byte)(gmt_unix_time >>  8);
  58         random_bytes[3] = (byte)gmt_unix_time;
  59     }
  60 
  61     RandomCookie(HandshakeInStream m) throws IOException {
  62         random_bytes = new byte[32];
  63         m.read(random_bytes, 0, 32);
  64     }
  65 
  66     void send(HandshakeOutStream out) throws IOException {
  67         out.write(random_bytes, 0, 32);
  68     }
  69 
  70     void print(PrintStream s) {
  71         int i, gmt_unix_time;
  72 
  73         gmt_unix_time = random_bytes[0] << 24;
  74         gmt_unix_time += random_bytes[1] << 16;
  75         gmt_unix_time += random_bytes[2] << 8;
  76         gmt_unix_time += random_bytes[3];
  77 
  78         s.print("GMT: " + gmt_unix_time + " ");
  79         s.print("bytes = { ");
  80 
  81         for (i = 4; i < 32; i++) {
  82             if (i != 4) {
  83                 s.print(", ");
  84             }
  85             s.print(random_bytes[i] & 0x0ff);
  86         }
  87         s.println(" }");
  88     }
  89 }