plugins/m2m/wimax_tlv.c

   1 /* wimax_tlv.c
   2  * WiMax TLV handling functions
   3  *
   4  * Copyright (c) 2007 by Intel Corporation.
   5  *
   6  * Author: Lu Pan <lu.pan@intel.com>
   7  *
   8  * $Id$
   9  *
  10  * Wireshark - Network traffic analyzer
  11  * By Gerald Combs <gerald@wireshark.org>
  12  * Copyright 1999 Gerald Combs
  13  *
  14  * This program is free software; you can redistribute it and/or
  15  * modify it under the terms of the GNU General Public License
  16  * as published by the Free Software Foundation; either version 2
  17  * of the License, or (at your option) any later version.
  18  *
  19  * This program is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with this program; if not, write to the Free Software
  26  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  27  */
  28
  29 /*************************************************************/
  30 /*   ----------------------- NOTE -------------------------  */
  31 /* There is an identical copy of this file, wimax_tlv.c, in  */
  32 /* both .../plugins/m2m and .../plugins/wimax.  If either    */
  33 /* one needs to be modified, please be sure to copy the file */
  34 /* to the sister directory and check it in there also.       */
  35 /* This prevents having to generate a complicated            */
  36 /* Makefile.nmake in .../plugins/m2m.                        */
  37 /*************************************************************/
  38
  39 #ifdef HAVE_CONFIG_H
  40 #include "config.h"
  41 #endif
  42
  43 #include <plugins/wimax/wimax_tlv.h>
  44
  45 /*************************************************************/
  46 /* init_tlv_info()                                           */
  47 /* retrive the tlv information from specified tvb and offset */
  48 /* parameter:                                                */
  49 /*   this - pointer of a tlv information data structure      */
  50 /* return:                                                   */
  51 /*   0-success                                               */
  52 /*   !=0-the invalid size of the TLV length (failed)         */
  53 /*************************************************************/
  54 gint init_tlv_info(tlv_info_t *this, tvbuff_t *tvb, gint offset)
  55 {
  56         guint tlv_len;
  57
  58         /* get TLV type */
  59         this->type = (guint8)tvb_get_guint8( tvb, offset );
  60         /* get TLV length */
  61         tlv_len = (guint)tvb_get_guint8( tvb, (offset + 1) );
  62         /* set the TLV value offset */
  63         this->value_offset = 2;
  64         /* adjust for multiple-byte TLV length */
  65         if((tlv_len & WIMAX_TLV_EXTENDED_LENGTH_MASK) != 0)
  66         {       /* multiple bytes TLV length */
  67                 this->length_type = 1;
  68                 /* get the size of the TLV length */
  69                 tlv_len = (tlv_len & WIMAX_TLV_LENGTH_MASK);
  70                 this->size_of_length = tlv_len;
  71                 /* update the TLV value offset */
  72                 this->value_offset += tlv_len;
  73                 switch (tlv_len)
  74                 {
  75                         case 0:
  76                                 this->length = 0;  /* no length */
  77                         break;
  78                         case 1:
  79                                 this->length = (gint32)tvb_get_guint8( tvb, (offset + 2) ); /* 8 bit */
  80                         break;
  81                         case 2:
  82                                 this->length = (gint32)tvb_get_ntohs( tvb, (offset + 2) ); /* 16 bit */
  83                         break;
  84                         case 3:
  85                                 this->length = (gint32)tvb_get_ntoh24( tvb, (offset + 2) ); /* 24 bit */
  86                         break;
  87                         case 4:
  88                                 this->length = (gint32)tvb_get_ntohl( tvb, (offset + 2) ); /* 32 bit */
  89                         break;
  90                         default:
  91                                 /* mark invalid tlv */
  92                                 this->valid = 0;
  93                                 /* failed, return the invalid size of the tlv length */
  94                                 return (gint)tlv_len;
  95                         break;
  96                 }
  97         }
  98         else    /* single byte length */
  99         {
 100                 this->length_type = 0;
 101                 this->size_of_length = 0;
 102                 this->length = (gint32)tlv_len;
 103         }
 104         /* mark valid tlv */
 105         this->valid = 1;
 106         /* success */
 107         return 0;
 108 }
 109
 110 /*************************************************************/
 111 /* get_tlv_type()                                            */
 112 /* get the tlv type of the specified tlv information         */
 113 /* parameter:                                                */
 114 /*   this - pointer of a tlv information data structure      */
 115 /* return:                                                   */
 116 /*   >=0 - TLV type                                           */
 117 /*   =-1 - invalid tlv info                                  */
 118 /*************************************************************/
 119 gint get_tlv_type(tlv_info_t *this)
 120 {
 121         if(this->valid)
 122                 return (gint)this->type;
 123         return -1;
 124 }
 125
 126 /**************************************************************/
 127 /* get_tlv_size_of_length()                                   */
 128 /* get the size of tlv length of the specified tlv information*/
 129 /* parameter:                                                 */
 130 /*   this - pointer of a tlv information data structure       */
 131 /* return:                                                    */
 132 /*   >=0 - the size of TLV length                              */
 133 /*   =-1 - invalid tlv info                                   */
 134 /**************************************************************/
 135 gint get_tlv_size_of_length(tlv_info_t *this)
 136 {
 137         if(this->valid)
 138                 return (gint)this->size_of_length;
 139         return -1;
 140 }
 141
 142 /*************************************************************/
 143 /* get_tlv_length()                                          */
 144 /* get the tlv length of the specified tlv information       */
 145 /* parameter:                                                */
 146 /*   this - pointer of a tlv information data structure      */
 147 /* return:                                                   */
 148 /*   >=0 - TLV length                                         */
 149 /*   =-1 - invalid tlv info                                  */
 150 /*************************************************************/
 151 gint32 get_tlv_length(tlv_info_t *this)
 152 {
 153         if(this->valid)
 154                 return (gint32)this->length;
 155         return -1;
 156 }
 157
 158 /*************************************************************/
 159 /* get_tlv_value_offset()                                    */
 160 /* get the tlv value offset of the specified tlv information */
 161 /* parameter:                                                */
 162 /*   this - pointer of a tlv information data structure      */
 163 /* return:                                                   */
 164 /*   >0 - TLV value offset in byte                           */
 165 /*   =-1 - invalid tlv info                                  */
 166 /*************************************************************/
 167 gint get_tlv_value_offset(tlv_info_t *this)
 168 {
 169         if(this->valid)
 170                 return (gint)this->value_offset;
 171         return -1;
 172 }
 173
 174 /*************************************************************/
 175 /* get_tlv_length_type()                                     */
 176 /* get the tlv length type of the specified tlv information  */
 177 /* parameter:                                                */
 178 /*   this - pointer of a tlv information data structure      */
 179 /* return:                                                   */
 180 /*   0 - single byte TLV length                              */
 181 /*   1 - multiple bytes TLV length                           */
 182 /*************************************************************/
 183 gint get_tlv_length_type(tlv_info_t *this)
 184 {
 185         if(this->valid)
 186                 return (gint)this->length_type;
 187         return -1;
 188 }