nexmon – Rev 1

Subversion Repositories:
Rev:
/* packet-vendor.c
 * Routines for Vendor Specific Encodings dissection
 * Copyright 2002, Anand V. Narwani <anand[AT]narwani.org>
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <gerald@wireshark.org>
 * Copyright 1998 Gerald Combs
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */


/* Notes to Adding dissectors for Vendor specific TLV's:
 * 1. Create a dissect_<vendorname> function with the following prototype:
 *   dissect_foovendor(tvbuff_t *tvb, proto_tree *tree, gint vsif_len)
 * 2. vsif_len will be the *entire* length of the vsif TLV (including the
 *   Vendor Id TLV, which is 5 bytes long).
 * 3. Create a new 'case' statement in dissect_vsif, for your specific Vendor
 *   id.
 * 4. In that 'case' statement you will make the following calls:
 *   (assume for this example that your vendor id is 0x000054)
 *   #define VENDOR_FOOVENDOR 0x00054
 *   case VENDOR_FOOVENDOR:
 *      proto_item_append_text (it, " (foo vendor)");
 *      dissect_foovendor (tvb, vsif_tree, vsif_len);
 *      break;
 * 5.  Please see dissect_cisco for an example of how to do this.
 */

#include "config.h"

#include <epan/packet.h>
#include <epan/exceptions.h>

/* Define Vendor ID's here */
#define VENDOR_CISCO 0x00000C

void proto_register_docsis_vsif(void);
void proto_reg_handoff_docsis_vsif(void);

/* Initialize the protocol and registered fields */
static int proto_docsis_vsif = -1;
static int hf_docsis_vsif_vendorid = -1;
static int hf_docsis_vsif_vendor_unknown = -1;
static int hf_docsis_vsif_cisco_numphones = -1;
/* static int hf_docsis_vsif_cisco_ipprec = -1; */
static int hf_docsis_vsif_cisco_ipprec_val = -1;
static int hf_docsis_vsif_cisco_ipprec_bw = -1;
static int hf_docsis_vsif_cisco_config_file = -1;

/* Initialize the subtree pointers */
static gint ett_docsis_vsif = -1;
static gint ett_docsis_vsif_ipprec = -1;

static const value_string vendorid_vals[] = {
  {VENDOR_CISCO, "Cisco Systems, Inc."},
  {0, NULL},
};

/* Forward Declarations for vendor specific dissectors */
static void dissect_cisco (tvbuff_t * tvb, proto_tree * tree,
                           gint vsif_len);

/* Dissection */
static int
dissect_vsif (tvbuff_t * tvb, packet_info * pinfo _U_, proto_tree * tree, void* data _U_)
{
  proto_item *it;
  proto_tree *vsif_tree;
  guint8 type;
  guint8 length;
  guint32 value;
  gint vsif_len;

  /* get the reported length of the VSIF TLV */
  vsif_len = tvb_reported_length_remaining (tvb, 0);

  /* The first TLV in the VSIF encodings must be type 0x08 (Vendor ID) and
   * length 3.
   */
  type = tvb_get_guint8 (tvb, 0);
  if (type != 0x08)
    {
      THROW (ReportedBoundsError);
    }

  length = tvb_get_guint8 (tvb, 1);
  if (length != 3)
    {
      THROW (ReportedBoundsError);
    }

  /* Extract the Value of the Vendor ID */
  value = tvb_get_ntoh24 (tvb, 2);
  if (tree)
    {
      it =
        proto_tree_add_protocol_format (tree, proto_docsis_vsif, tvb, 0, -1,
                                        "VSIF Encodings");
      vsif_tree = proto_item_add_subtree (it, ett_docsis_vsif);
      proto_tree_add_item (vsif_tree, hf_docsis_vsif_vendorid, tvb, 2, 3, ENC_BIG_ENDIAN);

      /* switch on the Vendor ID */
      switch (value)
        {
          case VENDOR_CISCO:
            proto_item_append_text (it, " (Cisco)");
            dissect_cisco (tvb, vsif_tree, vsif_len);
            break;
          default:
            proto_item_append_text (it, " (Unknown)");
            proto_tree_add_item (vsif_tree, hf_docsis_vsif_vendor_unknown, tvb,
                                 0, -1, ENC_NA);
            break;
        }

    }                           /* if(tree) */

    return tvb_captured_length(tvb);
}

/* Dissector for Cisco Vendor Specific TLV's */

#define NUM_PHONES      0x0a
#define IOS_CONFIG_FILE 0x80
#define IP_PREC         0x0b
#define IP_PREC_VAL     0x01
#define IP_PREC_BW      0x02

static void
dissect_cisco (tvbuff_t * tvb, proto_tree * tree, gint vsif_len)
{
  /* Start at pos = 5, since tvb includes the Vendor ID field */
  int pos = 5;
  guint8 type, length;
  proto_tree *ipprec_tree;
  int templen;

  while (pos < vsif_len)
    {
      /* Extract the type and length Fields from the TLV */
      type = tvb_get_guint8 (tvb, pos++);
      length = tvb_get_guint8 (tvb, pos++);
      switch (type)
        {
          case NUM_PHONES:
            proto_tree_add_item (tree, hf_docsis_vsif_cisco_numphones, tvb,
                                 pos, length, ENC_BIG_ENDIAN);
            break;
          case IP_PREC:
            ipprec_tree =
              proto_tree_add_subtree(tree, tvb, pos, length, ett_docsis_vsif_ipprec, NULL, "IP Precedence");
            /* Handle Sub-TLVs in IP Precedence */
            templen = pos + length;
            while (pos < templen)
              {
                type = tvb_get_guint8 (tvb, pos++);
                length = tvb_get_guint8 (tvb, pos++);
                switch (type)
                  {
                    case IP_PREC_VAL:
                      if (length != 1)
                        THROW (ReportedBoundsError);
                      proto_tree_add_item (ipprec_tree,
                                           hf_docsis_vsif_cisco_ipprec_val, tvb,
                                           pos, length, ENC_BIG_ENDIAN);
                      break;
                    case IP_PREC_BW:
                      if (length != 4)
                        THROW (ReportedBoundsError);
                      proto_tree_add_item (ipprec_tree,
                                           hf_docsis_vsif_cisco_ipprec_bw, tvb,
                                           pos, length, ENC_BIG_ENDIAN);
                      break;
                    default:
                      THROW (ReportedBoundsError);
                  }
                pos += length;
              }
            break;
          case IOS_CONFIG_FILE:
            proto_tree_add_item (tree, hf_docsis_vsif_cisco_config_file, tvb,
                                 pos, length, ENC_ASCII|ENC_NA);
        }
      pos += length;
    }
}

/* Register the protocol with Wireshark */
void
proto_register_docsis_vsif (void)
{
  static hf_register_info hf[] = {
    {&hf_docsis_vsif_vendorid,
     {"Vendor Id", "docsis_vsif.vendorid",
      FT_UINT24, BASE_HEX, VALS(vendorid_vals), 0x0,
      "Vendor Identifier", HFILL}
    },
    {&hf_docsis_vsif_vendor_unknown,
     {"VSIF Encodings", "docsis_vsif.unknown",
      FT_BYTES, BASE_NONE, NULL, 0x0,
      "Unknown Vendor", HFILL}
    },
    {&hf_docsis_vsif_cisco_numphones,
     {"Number of phone lines", "docsis_vsif.cisco.numphones",
      FT_UINT8, BASE_DEC, NULL, 0x0,
      NULL, HFILL}
    },
#if 0
    {&hf_docsis_vsif_cisco_ipprec,
     {"IP Precedence Encodings", "docsis_vsif.cisco.ipprec",
      FT_BYTES, BASE_NONE, NULL, 0x0,
      NULL, HFILL}
    },
#endif
    {&hf_docsis_vsif_cisco_ipprec_val,
     {"IP Precedence Value", "docsis_vsif.cisco.ipprec.value",
      FT_UINT8, BASE_DEC, NULL, 0x0,
      NULL, HFILL}
    },
    {&hf_docsis_vsif_cisco_ipprec_bw,
     {"IP Precedence Bandwidth", "docsis_vsif.cisco.ipprec.bw",
      FT_UINT8, BASE_DEC, NULL, 0x0,
      NULL, HFILL}
    },
    {&hf_docsis_vsif_cisco_config_file,
     {"IOS Config File", "docsis_vsif.cisco.iosfile",
      FT_STRING, BASE_NONE, NULL, 0x0,
      NULL, HFILL}
    },
  };

  static gint *ett[] = {
    &ett_docsis_vsif,
    &ett_docsis_vsif_ipprec,
  };

  proto_docsis_vsif =
    proto_register_protocol ("DOCSIS Vendor Specific Encodings",
                             "DOCSIS VSIF", "docsis_vsif");

  proto_register_field_array (proto_docsis_vsif, hf, array_length (hf));
  proto_register_subtree_array (ett, array_length (ett));

  register_dissector ("docsis_vsif", dissect_vsif, proto_docsis_vsif);
}

void
proto_reg_handoff_docsis_vsif (void)
{
#if 0
  dissector_handle_t docsis_vsif_handle;

  docsis_vsif_handle = find_dissector ("docsis_vsif");
  dissector_add_uint ("docsis", 0xFD, docsis_vsif_handle);
#endif
}

/*
 * Editor modelines  -  http://www.wireshark.org/tools/modelines.html
 *
 * Local Variables:
 * c-basic-offset: 2
 * tab-width: 8
 * indent-tabs-mode: nil
 * End:
 *
 * ex: set shiftwidth=2 tabstop=8 expandtab:
 * :indentSize=2:tabSize=8:noTabs=true:
 */