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/* packet-cdp.c
* Routines for the disassembly of the "Cisco Discovery Protocol"
* (c) Copyright Hannes R. Boehm <hannes@boehm.org>
*
* $Id: packet-cdp.c,v 1.16 1999/10/16 14:27:00 deniel Exp $
*
* Ethereal - Network traffic analyzer
* By Gerald Combs <gerald@zing.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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include "config.h"
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#include <stdlib.h>
#include <string.h>
#include <glib.h>
#include "packet.h"
/* Offsets in TLV structure. */
#define TLV_TYPE 0
#define TLV_LENGTH 2
static int proto_cdp = -1;
static int hf_cdp_version = -1;
static int hf_cdp_flags = -1;
static int hf_cdp_ttl = -1;
static int hf_cdp_tlvtype = -1;
static int hf_cdp_tlvlength = -1;
static void
add_multi_line_string_to_tree(proto_tree *tree, gint start, gint len,
const gchar *prefix, const gchar *string);
#define TYPE_MGMT_ADDR 0
#define TYPE_CHASSIS_ID 1
#define TYPE_2 2
#define TYPE_PORT 3
#define TYPE_IOS_VERSION 5
#define TYPE_PLATFORM 6
#define TYPE_MGMT_IP_ADDR 0x01cc
static const value_string type_vals[] = {
{ TYPE_MGMT_ADDR, "Mgmt addr?" },
{ TYPE_CHASSIS_ID, "Chassis ID" },
{ TYPE_2, "Unknown" },
{ TYPE_PORT, "Port" },
{ TYPE_IOS_VERSION, "Software version" },
{ TYPE_PLATFORM, "Platform" },
{ TYPE_MGMT_IP_ADDR, "Mgmt IP" },
{ 0, NULL },
};
void
dissect_cdp(const u_char *pd, int offset, frame_data *fd, proto_tree *tree) {
proto_item *ti;
proto_tree *cdp_tree = NULL;
guint16 type;
guint16 length;
char *type_str;
char *stringmem;
proto_item *tlvi;
proto_tree *tlv_tree;
if (check_col(fd, COL_PROTOCOL))
col_add_str(fd, COL_PROTOCOL, "CDP");
if (check_col(fd, COL_INFO))
col_add_str(fd, COL_INFO, "Cisco Discovery Protocol");
if(tree){
ti = proto_tree_add_item(tree, proto_cdp, offset, END_OF_FRAME, NULL);
cdp_tree = proto_item_add_subtree(ti, ETT_CDP);
/* CDP header */
proto_tree_add_item(cdp_tree, hf_cdp_version, offset, 1, pd[offset]);
offset += 1;
proto_tree_add_item_format(cdp_tree, hf_cdp_flags, offset, 1,
pd[offset],
"Flags: %x (unknown)", pd[offset]);
offset += 1;
proto_tree_add_item_format(cdp_tree, hf_cdp_ttl, offset, 2,
pntohs(&pd[offset]),
"TTL: %u (unknown)", pntohs(&pd[offset]));
offset += 2;
while( IS_DATA_IN_FRAME(offset) ){
type = pntohs(&pd[offset + TLV_TYPE]);
length = pntohs(&pd[offset + TLV_LENGTH]);
type_str = val_to_str(type, type_vals,
"Unknown (0x%04x)");
switch( type ){
case TYPE_MGMT_ADDR:
/* ??? Mgmt Addr; in this one, the "length"
field doesn't include the length of the
type and length fields. */
tlvi = proto_tree_add_text(cdp_tree, offset,
length + 4, "Type: %s, length: %u",
type_str, length);
tlv_tree = proto_item_add_subtree(tlvi,
ETT_CDP_TLV);
proto_tree_add_item(tlv_tree, hf_cdp_tlvtype,
offset + TLV_TYPE, 2, type);
proto_tree_add_item(tlv_tree, hf_cdp_tlvlength,
offset + TLV_LENGTH, 2, length);
if (length > 0) {
proto_tree_add_text(tlv_tree,
offset + 4, length, "Data");
}
offset+=length + 4;
break;
case TYPE_CHASSIS_ID:
/* ??? Chassis ID */
tlvi = proto_tree_add_text(cdp_tree, offset,
length, "Chassis ID: %s",
&pd[offset+4]);
tlv_tree = proto_item_add_subtree(tlvi,
ETT_CDP_TLV);
proto_tree_add_item(tlv_tree, hf_cdp_tlvtype,
offset + TLV_TYPE, 2, type);
proto_tree_add_item(tlv_tree, hf_cdp_tlvlength,
offset + TLV_LENGTH, 2, length);
proto_tree_add_text(tlv_tree, offset + 4,
length - 4, "Chassis ID: %s",
&pd[offset+4]);
offset+=length;
break;
case TYPE_2:
/* this is quite strange: this tlv contains
no data itself but two tlvs which
calculate the length without the 2 byte
type and 2 byte length field */
tlvi = proto_tree_add_text(cdp_tree, offset,
4, "Type: %u (unknown), second field: %u",
type, length);
tlv_tree = proto_item_add_subtree(tlvi,
ETT_CDP_TLV);
proto_tree_add_item(tlv_tree, hf_cdp_tlvtype,
offset + TLV_TYPE, 2, type);
proto_tree_add_text(tlv_tree,
offset + TLV_LENGTH, 2, "Second field: %u",
length);
offset+=4;
break;
case TYPE_PORT:
/* ??? Port */
tlvi = proto_tree_add_text(cdp_tree, offset,
length, "Sent through Interface: %s",
&pd[offset+4]);
tlv_tree = proto_item_add_subtree(tlvi,
ETT_CDP_TLV);
proto_tree_add_item(tlv_tree, hf_cdp_tlvtype,
offset + TLV_TYPE, 2, type);
proto_tree_add_item(tlv_tree, hf_cdp_tlvlength,
offset + TLV_LENGTH, 2, length);
proto_tree_add_text(tlv_tree, offset + 4,
length - 4, "Sent through Interface: %s",
&pd[offset+4]);
offset+=length;
break;
case TYPE_IOS_VERSION:
/* ??? IOS Version */
add_multi_line_string_to_tree(cdp_tree,
offset + 4, length - 4, "Software Version: ",
&pd[offset+4] );
offset+=length;
break;
case TYPE_PLATFORM:
/* ??? platform */
stringmem = malloc(length);
memset(stringmem, '\0', length);
memcpy(stringmem, &pd[offset+4], length - 4 );
tlvi = proto_tree_add_text(cdp_tree,
offset, length, "Platform: %s",
stringmem);
tlv_tree = proto_item_add_subtree(tlvi,
ETT_CDP_TLV);
proto_tree_add_item(tlv_tree, hf_cdp_tlvtype,
offset + TLV_TYPE, 2, type);
proto_tree_add_item(tlv_tree, hf_cdp_tlvlength,
offset + TLV_LENGTH, 2, length);
proto_tree_add_text(tlv_tree, offset + 4,
length - 4, "Platform: %s", stringmem);
free(stringmem);
offset+=length;
break;
case TYPE_MGMT_IP_ADDR:
/* ??? Mgmt IP Addr; in this one, the "length"
field doesn't include the length of the
type and length fields. */
tlvi = proto_tree_add_text(cdp_tree,
offset, length + 4, "Mgmt IP: %s",
ip_to_str(&pd[offset+4]));
tlv_tree = proto_item_add_subtree(tlvi,
ETT_CDP_TLV);
proto_tree_add_item(tlv_tree, hf_cdp_tlvtype,
offset + TLV_TYPE, 2, type);
proto_tree_add_item(tlv_tree, hf_cdp_tlvlength,
offset + TLV_LENGTH, 2, length);
proto_tree_add_text(tlv_tree, offset + 4,
length, "IP address: %s",
ip_to_str(&pd[offset+4]));
offset+=length + 4;
break;
default:
tlvi = proto_tree_add_text(cdp_tree, offset,
length, "Type: %s, length: %u",
type_str, length);
tlv_tree = proto_item_add_subtree(tlvi,
ETT_CDP_TLV);
proto_tree_add_item(tlv_tree, hf_cdp_tlvtype,
offset + TLV_TYPE, 2, type);
proto_tree_add_item(tlv_tree, hf_cdp_tlvlength,
offset + TLV_LENGTH, 2, length);
if (length > 4) {
proto_tree_add_text(tlv_tree,
offset + 4, length - 4, "Data");
} else
return;
offset+=length;
}
}
dissect_data(pd, offset, fd, cdp_tree);
}
}
static void
add_multi_line_string_to_tree(proto_tree *tree, gint start, gint len,
const gchar *prefix, const gchar *string)
{
int prefix_len;
int i;
char blanks[64+1];
const gchar *p, *q;
int line_len;
int data_len;
prefix_len = strlen(prefix);
if (prefix_len > 64)
prefix_len = 64;
for (i = 0; i < prefix_len; i++)
blanks[i] = ' ';
blanks[i] = '\0';
p = string;
for (;;) {
q = strchr(p, '\n');
if (q != NULL) {
line_len = q - p;
data_len = line_len + 1;
} else {
line_len = strlen(p);
data_len = line_len;
}
proto_tree_add_text(tree, start, data_len, "%s%.*s", prefix,
line_len, p);
if (q == NULL)
break;
p += data_len;
start += data_len;
prefix = blanks;
}
}
void
proto_register_cdp(void)
{
static hf_register_info hf[] = {
{ &hf_cdp_version,
{ "Version", "cdp.version", FT_UINT8, BASE_DEC, NULL, 0x0,
"" }},
{ &hf_cdp_flags,
{ "Flags", "cdp.flags", FT_UINT8, BASE_HEX, NULL, 0x0,
"" }},
{ &hf_cdp_ttl,
{ "TTL", "cdp.ttl", FT_UINT16, BASE_DEC, NULL, 0x0,
"" }},
{ &hf_cdp_tlvtype,
{ "Type", "cdp.tlv.type", FT_UINT16, BASE_HEX, VALS(type_vals), 0x0,
"" }},
{ &hf_cdp_tlvlength,
{ "Length", "cdp.tlv.len", FT_UINT16, BASE_DEC, NULL, 0x0,
"" }},
};
proto_cdp = proto_register_protocol("Cisco Discovery Protocol", "cdp");
proto_register_field_array(proto_cdp, hf, array_length(hf));
}
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