1 /*
   2  * Copyright (c) 1996, 2015, 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 package sun.security.ssl;
  27 
  28 /**
  29  * SSL/TLS/DTLS records, as pulled off (and put onto) a TCP stream.  This is
  30  * the base interface, which defines common information and interfaces
  31  * used by both Input and Output records.
  32  *
  33  * @author David Brownell
  34  */
  35 interface Record {
  36 
  37     /*
  38      * There are four record types, which are part of the interface
  39      * to this level (along with the maximum record size).
  40      *
  41      * enum { change_cipher_spec(20), alert(21), handshake(22),
  42      *      application_data(23), (255) } ContentType;
  43      */
  44     static final byte   ct_change_cipher_spec = 20;
  45     static final byte   ct_alert = 21;
  46     static final byte   ct_handshake = 22;
  47     static final byte   ct_application_data = 23;
  48 
  49     static final int    maxMacSize = 48;        // the max supported MAC or
  50                                                 // AEAD tag size
  51     static final int    maxDataSize = 16384;    // 2^14 bytes of data
  52     static final int    maxPadding = 256;       // block cipher padding
  53     static final int    maxIVLength = 16;       // the max supported IV length
  54 
  55     static final int    maxFragmentSize = 18432;    // the max fragment size
  56                                                     // 2^14 + 2048
  57 
  58     /*
  59      * System property to enable/disable CBC protection in SSL3/TLS1.
  60      */
  61     static final boolean enableCBCProtection =
  62             Debug.getBooleanProperty("jsse.enableCBCProtection", true);
  63 
  64     /*
  65      * The overflow values of integers of 8, 16 and 24 bits.
  66      */
  67     static final int OVERFLOW_OF_INT08 = (1 << 8);
  68     static final int OVERFLOW_OF_INT16 = (1 << 16);
  69     static final int OVERFLOW_OF_INT24 = (1 << 24);
  70 
  71     /**
  72      * Return a description for the given content type.
  73      */
  74     static String contentName(byte contentType) {
  75         switch (contentType) {
  76         case ct_change_cipher_spec:
  77             return "Change Cipher Spec";
  78         case ct_alert:
  79             return "Alert";
  80         case ct_handshake:
  81             return "Handshake";
  82         case ct_application_data:
  83             return "Application Data";
  84         default:
  85             return "contentType = " + contentType;
  86         }
  87     }
  88 
  89     static boolean isValidContentType(byte contentType) {
  90         return (contentType == 20) || (contentType == 21) ||
  91                (contentType == 22) || (contentType == 23);
  92     }
  93 }