1 /*

     2  * Copyright (c) 1996, 2012, 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.security.SecureRandom;

    30 import javax.net.ssl.SSLProtocolException;

    31 

    32 /**

    33  * Encapsulates an SSL session ID.  SSL Session IDs are not reused by

    34  * servers during the lifetime of any sessions it created.  Sessions may

    35  * be used by many connections, either concurrently (for example, two

    36  * connections to a web server at the same time) or sequentially (over as

    37  * long a time period as is allowed by a given server).

    38  *

    39  * @author Satish Dharmaraj

    40  * @author David Brownell

    41  */

    42 final

    43 class SessionId

    44 {

    45     static int MAX_LENGTH = 32;

    46     private byte[] sessionId;          // max 32 bytes

    47 

    48     /** Constructs a new session ID ... perhaps for a rejoinable session */

    49     SessionId (boolean isRejoinable, SecureRandom generator)

    50     {

    51         if (isRejoinable)

    52             // this will be unique, it's a timestamp plus much randomness

    53             sessionId = new RandomCookie (generator).random_bytes;

    54         else

    55             sessionId = new byte [0];

    56     }

    57 

    58     /** Constructs a session ID from a byte array (max size 32 bytes) */

    59     SessionId (byte[] sessionId)

    60         { this.sessionId = sessionId; }

    61 

    62     /** Returns the length of the ID, in bytes */

    63     int length ()

    64         { return sessionId.length; }

    65 

    66     /** Returns the bytes in the ID.  May be an empty array.  */

    67     byte[] getId ()

    68     {

    69         return sessionId.clone ();

    70     }

    71 

    72     /** Returns the ID as a string */

    73     @Override

    74     public String toString ()

    75     {

    76         int             len = sessionId.length;

    77         StringBuilder    sb = new StringBuilder (10 + 2 * len);

    78 

    79         sb.append("{");

    80         for (int i = 0; i < len; i++) {

    81             sb.append(0x0ff & sessionId[i]);

    82             if (i != (len - 1))

    83                 sb.append (", ");

    84         }

    85         sb.append("}");

    86         return sb.toString ();

    87     }

    88 

    89 

    90     /** Returns a value which is the same for session IDs which are equal */

    91     @Override

    92     public int hashCode ()

    93     {

    94         int     retval = 0;

    95 

    96         for (int i = 0; i < sessionId.length; i++)

    97             retval += sessionId [i];

    98         return retval;

    99     }

   100 

   101     /** Returns true if the parameter is the same session ID */

   102     @Override

   103     public boolean equals (Object obj)

   104     {

   105         if (!(obj instanceof SessionId))

   106             return false;

   107 

   108         SessionId s = (SessionId) obj;

   109         byte[] b = s.getId ();

   110 

   111         if (b.length != sessionId.length)

   112             return false;

   113         for (int i = 0; i < sessionId.length; i++) {

   114             if (b [i] != sessionId [i])

   115                 return false;

   116         }

   117         return true;

   118     }

   119 

   120     /**

   121      * Checks the length of the session ID to make sure it sits within

   122      * the range called out in the specification

   123      */

   124     void checkLength(ProtocolVersion pv) throws SSLProtocolException {

   125         // As of today all versions of TLS have a 32-byte maximum length.

   126         // In the future we can do more here to support protocol versions

   127         // that may have longer max lengths.

   128         if (sessionId.length > MAX_LENGTH) {

   129             throw new SSLProtocolException("Invalid session ID length (" +

   130                     sessionId.length + " bytes)");

   131         }

   132     }

   133 

   134 }