/* packet-cdp.c
- * Routines for the disassembly of the "Cisco Discovery Protocoll"
+ * Routines for the disassembly of the "Cisco Discovery Protocol"
* (c) Copyright Hannes R. Boehm <hannes@boehm.org>
*
- * $Id: packet-cdp.c,v 1.4 1999/01/05 00:08:49 hannes Exp $
+ * $Id: packet-cdp.c,v 1.48 2002/08/18 15:30:38 gerald Exp $
*
* Ethereal - Network traffic analyzer
- * By Gerald Combs <gerald@zing.org>
+ * By Gerald Combs <gerald@ethereal.com>
* 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
#include "config.h"
-#include <gtk/gtk.h>
-
-#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
-#ifdef HAVE_SYS_TYPES_H
-#include <sys/types.h>
-#endif
+#include <glib.h>
+#include <epan/packet.h>
+#include <epan/strutil.h>
+#include "nlpid.h"
-#ifdef HAVE_NETINET_IN_H
-#include <netinet/in.h>
-#endif
+/*
+ * See
+ *
+ * http://www.cisco.com/univercd/cc/td/doc/product/lan/trsrb/frames.htm
+ *
+ * for some information on CDP.
+ */
-#include "ethereal.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_checksum = -1;
+static int hf_cdp_ttl = -1;
+static int hf_cdp_tlvtype = -1;
+static int hf_cdp_tlvlength = -1;
-void
-dissect_cdp(const u_char *pd, int offset, frame_data *fd, GtkTree *tree) {
- GtkWidget *cdp_tree = NULL, *ti;
-
- typedef struct _e_tlv_struct{
- gint16 type;
- gint16 length;
- } e_tlv_struct;
+static gint ett_cdp = -1;
+static gint ett_cdp_tlv = -1;
+static gint ett_cdp_address = -1;
+static gint ett_cdp_capabilities = -1;
- typedef struct _e_cdp_hdr{
- char version;
- char flags;
- gint16 ttl;
- } e_cdp_hdr;
+static dissector_handle_t data_handle;
- e_tlv_struct *tlv;
- e_cdp_hdr *cdp_hdr;
- char *stringmem;
- gint32 mgmt_ip;
+static int
+dissect_address_tlv(tvbuff_t *tvb, int offset, int length, proto_tree *tree);
+static void
+dissect_capabilities(tvbuff_t *tvb, int offset, int length, proto_tree *tree);
+static void
+add_multi_line_string_to_tree(proto_tree *tree, tvbuff_t *tvb, gint start,
+ gint len, const gchar *prefix);
+#define TYPE_DEVICE_ID 0x0001
+#define TYPE_ADDRESS 0x0002
+#define TYPE_PORT_ID 0x0003
+#define TYPE_CAPABILITIES 0x0004
+#define TYPE_IOS_VERSION 0x0005
+#define TYPE_PLATFORM 0x0006
+#define TYPE_IP_PREFIX 0x0007
- 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");
+#define TYPE_VTP_MGMT_DOMAIN 0x0009 /* Guessed, from tcpdump */
+#define TYPE_NATIVE_VLAN 0x000a /* Guessed, from tcpdump */
+#define TYPE_DUPLEX 0x000b /* Guessed, from tcpdump */
- if(tree){
- ti = add_item_to_tree(GTK_WIDGET(tree), offset, (fd->cap_len - offset),
- "Cisco Discovery Protocol");
- cdp_tree = gtk_tree_new();
- add_subtree(ti, cdp_tree, ETT_CDP);
+static const value_string type_vals[] = {
+ { TYPE_DEVICE_ID, "Device ID" },
+ { TYPE_ADDRESS, "Addresses" },
+ { TYPE_PORT_ID, "Port ID" },
+ { TYPE_CAPABILITIES, "Capabilities" },
+ { TYPE_IOS_VERSION, "Software version" },
+ { TYPE_PLATFORM, "Platform" },
+ { TYPE_IP_PREFIX, "IP Prefix (used for ODR)" },
+ { TYPE_VTP_MGMT_DOMAIN, "VTP Management Domain" },
+ { TYPE_NATIVE_VLAN, "Native VLAN" },
+ { TYPE_DUPLEX, "Duplex" },
+ { 0, NULL },
+};
- /* CDP header */
- cdp_hdr = (e_cdp_hdr *) &pd[offset];
- add_item_to_tree(cdp_tree, offset, 0, "under development (hannes@boehm.org)");
- add_item_to_tree(cdp_tree, offset, 1, "Version: %d", cdp_hdr->version);
- add_item_to_tree(cdp_tree, offset+1, 1, "Flags (unknown)");
- add_item_to_tree(cdp_tree, offset+2, 2, "TTL (unknown)");
- offset+=4;
-
- /* CVS -> exit here
- dissect_data(pd, offset, fd, (GtkTree *) cdp_tree);
- return;
- */
+static void
+dissect_cdp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+ proto_item *ti;
+ proto_tree *cdp_tree = NULL;
+ int offset = 0;
+ guint16 type;
+ guint16 length;
+ proto_item *tlvi;
+ proto_tree *tlv_tree;
+ int real_length;
+ guint32 naddresses;
+ int addr_length;
+
+ if (check_col(pinfo->cinfo, COL_PROTOCOL))
+ col_set_str(pinfo->cinfo, COL_PROTOCOL, "CDP");
+ if (check_col(pinfo->cinfo, COL_INFO))
+ col_set_str(pinfo->cinfo, COL_INFO, "Cisco Discovery Protocol");
+
+ if (tree){
+ ti = proto_tree_add_item(tree, proto_cdp, tvb, offset, -1, FALSE);
+ cdp_tree = proto_item_add_subtree(ti, ett_cdp);
- while( offset <= fd->cap_len ){
- tlv = (e_tlv_struct *) &pd[offset];
- switch( ntohs(tlv->type) ){
- case 0: /* ??? Mgmt Addr */
- offset+=ntohs(tlv->length) + 4;
- break;
- case 1: /* ??? Chasis ID */
- add_item_to_tree(cdp_tree, offset + 4, ntohs(tlv->length) - 4, "Chassis ID: %s", &pd[offset+4] );
- offset+=ntohs(tlv->length);
- break;
- case 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
- */
- offset+=4;
- break;
- case 3: /* ??? Port */
- add_item_to_tree(cdp_tree, offset + 4, ntohs(tlv->length) - 4, "Sent through Interface: %s", &pd[offset+4] );
- offset+=ntohs(tlv->length);
- break;
- case 5: /* ??? IOS Version */
- add_item_to_tree(cdp_tree, offset + 4, ntohs(tlv->length) - 4,
- "Software Version: %s", &pd[offset+4] );
- offset+=ntohs(tlv->length);
- break;
- case 6: /* ??? platform */
-
- stringmem = malloc(ntohs(tlv->length));
- bzero(stringmem, ntohs(tlv->length));
- memcpy(stringmem, &pd[offset+4], ntohs(tlv->length) - 4 );
- add_item_to_tree(cdp_tree, offset + 4, ntohs(tlv->length) - 4,
- "Platform: %s", stringmem );
- free(stringmem);
- offset+=ntohs(tlv->length);
- break;
- case 0x01cc: /* ??? Mgmt Addr */
- memcpy(&mgmt_ip, &pd[offset+4], 4);
- add_item_to_tree(cdp_tree, offset + 4, ntohs(tlv->length),
- "Mgmt IP: %s", inet_ntoa((mgmt_ip)) );
- offset+=ntohs(tlv->length) + 4;
- break;
- default:
-/*
- if( ntohs(tlv->type) > 512){
- dissect_data(pd, offset, fd, (GtkTree *) cdp_tree);
- return;
- }
-*/
-/*
- add_item_to_tree(cdp_tree, offset, 2, "Type: %d", ntohs(tlv->type));
- add_item_to_tree(cdp_tree, offset + 2, 2, "Length: %d", ntohs(tlv->length));
- add_item_to_tree(cdp_tree, offset + 4, ntohs(tlv->length) - 4, "Data");
-*/
+ /* CDP header */
+ proto_tree_add_item(cdp_tree, hf_cdp_version, tvb, offset, 1, FALSE);
+ offset += 1;
+ proto_tree_add_uint_format(cdp_tree, hf_cdp_ttl, tvb, offset, 1,
+ tvb_get_guint8(tvb, offset),
+ "TTL: %u seconds",
+ tvb_get_guint8(tvb, offset));
+ offset += 1;
+ proto_tree_add_item(cdp_tree, hf_cdp_checksum, tvb, offset, 2, FALSE);
+ offset += 2;
+
+ while (tvb_reported_length_remaining(tvb, offset) != 0) {
+ type = tvb_get_ntohs(tvb, offset + TLV_TYPE);
+ length = tvb_get_ntohs(tvb, offset + TLV_LENGTH);
+ if (length < 4) {
+ tlvi = proto_tree_add_text(cdp_tree, tvb, offset, 4,
+ "TLV with invalid length %u (< 4)",
+ length);
+ tlv_tree = proto_item_add_subtree(tlvi, ett_cdp_tlv);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvtype, tvb,
+ offset + TLV_TYPE, 2, type);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvlength, tvb,
+ offset + TLV_LENGTH, 2, length);
+ offset += 4;
+ break;
+ }
+
+ switch (type) {
+
+ case TYPE_DEVICE_ID:
+ /* Device ID */
+ tlvi = proto_tree_add_text(cdp_tree, tvb, offset,
+ length, "Device ID: %.*s",
+ length - 4,
+ tvb_get_ptr(tvb, offset + 4, length - 4));
+ tlv_tree = proto_item_add_subtree(tlvi, ett_cdp_tlv);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvtype, tvb,
+ offset + TLV_TYPE, 2, type);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvlength, tvb,
+ offset + TLV_LENGTH, 2, length);
+ proto_tree_add_text(tlv_tree, tvb, offset + 4,
+ length - 4, "Device ID: %.*s",
+ length - 4,
+ tvb_get_ptr(tvb, offset + 4, length - 4));
+ offset += length;
+ break;
+
+ case TYPE_ADDRESS:
+ /* Addresses */
+ tlvi = proto_tree_add_text(cdp_tree, tvb, offset,
+ length, "Addresses");
+ tlv_tree = proto_item_add_subtree(tlvi, ett_cdp_tlv);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvtype, tvb,
+ offset + TLV_TYPE, 2, type);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvlength, tvb,
+ offset + TLV_LENGTH, 2, length);
+ offset += 4;
+ length -= 4;
+ naddresses = tvb_get_ntohl(tvb, offset);
+ proto_tree_add_text(tlv_tree, tvb, offset, 4,
+ "Number of addresses: %u", naddresses);
+ offset += 4;
+ length -= 4;
+ while (naddresses != 0) {
+ addr_length = dissect_address_tlv(tvb, offset, length,
+ tlv_tree);
+ if (addr_length < 0)
+ break;
+ offset += addr_length;
+ length -= addr_length;
- offset+=ntohs(tlv->length);
+ naddresses--;
}
+ offset += length;
+ break;
- }
- dissect_data(pd, offset, fd, (GtkTree *) cdp_tree);
+ case TYPE_PORT_ID:
+ real_length = length;
+ if (tvb_get_guint8(tvb, offset + real_length) != 0x00) {
+ /* The length in the TLV doesn't appear to be the
+ length of the TLV, as the byte just past it
+ isn't the first byte of a 2-byte big-endian
+ small integer; make the length of the TLV the length
+ in the TLV, plus 4 bytes for the TLV type and length,
+ minus 1 because that's what makes one capture work. */
+ real_length = length + 3;
+ }
+ tlvi = proto_tree_add_text(cdp_tree, tvb, offset,
+ real_length, "Port ID: %.*s",
+ real_length - 4,
+ tvb_get_ptr(tvb, offset + 4, real_length - 4));
+ tlv_tree = proto_item_add_subtree(tlvi, ett_cdp_tlv);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvtype, tvb,
+ offset + TLV_TYPE, 2, type);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvlength, tvb,
+ offset + TLV_LENGTH, 2, length);
+ proto_tree_add_text(tlv_tree, tvb, offset + 4,
+ real_length - 4,
+ "Sent through Interface: %.*s",
+ real_length - 4,
+ tvb_get_ptr(tvb, offset + 4, real_length - 4));
+ offset += real_length;
+ break;
+
+ case TYPE_CAPABILITIES:
+ tlvi = proto_tree_add_text(cdp_tree, tvb, offset,
+ length, "Capabilities");
+ tlv_tree = proto_item_add_subtree(tlvi, ett_cdp_tlv);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvtype, tvb,
+ offset + TLV_TYPE, 2, type);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvlength, tvb,
+ offset + TLV_LENGTH, 2, length);
+ offset += 4;
+ length -= 4;
+ dissect_capabilities(tvb, offset, length, tlv_tree);
+ offset += length;
+ break;
+
+ case TYPE_IOS_VERSION:
+ tlvi = proto_tree_add_text(cdp_tree, tvb, offset,
+ length, "Software Version");
+ tlv_tree = proto_item_add_subtree(tlvi, ett_cdp_tlv);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvtype, tvb,
+ offset + TLV_TYPE, 2, type);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvlength, tvb,
+ offset + TLV_LENGTH, 2, length);
+ add_multi_line_string_to_tree(tlv_tree, tvb, offset + 4,
+ length - 4, "Software Version: ");
+ offset += length;
+ break;
+
+ case TYPE_PLATFORM:
+ /* ??? platform */
+ tlvi = proto_tree_add_text(cdp_tree, tvb,
+ offset, length, "Platform: %.*s",
+ length - 4,
+ tvb_get_ptr(tvb, offset + 4, length - 4));
+ tlv_tree = proto_item_add_subtree(tlvi, ett_cdp_tlv);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvtype, tvb,
+ offset + TLV_TYPE, 2, type);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvlength, tvb,
+ offset + TLV_LENGTH, 2, length);
+ proto_tree_add_text(tlv_tree, tvb, offset + 4,
+ length - 4, "Platform: %.*s",
+ length - 4,
+ tvb_get_ptr(tvb, offset + 4, length - 4));
+ offset += length;
+ break;
+ case TYPE_IP_PREFIX:
+ tlvi = proto_tree_add_text(cdp_tree, tvb, offset,
+ length, "IP Prefixes: %d",length/5);
+
+ /* the actual number of prefixes is (length-4)/5
+ but if the variable is not a "float" but "integer"
+ then length/5=(length-4)/5 :) */
+
+ tlv_tree = proto_item_add_subtree(tlvi, ett_cdp_tlv);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvtype, tvb,
+ offset + TLV_TYPE, 2, type);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvlength, tvb,
+ offset + TLV_LENGTH, 2, length);
+ offset += 4;
+ length -= 4;
+ while (length > 0) {
+ proto_tree_add_text(tlv_tree, tvb, offset, 5,
+ "IP Prefix = %s/%u",
+ ip_to_str(tvb_get_ptr(tvb, offset, 4)),
+ tvb_get_guint8(tvb,offset+4));
+ offset += 5;
+ length -= 5;
+ }
+ break;
+ case TYPE_VTP_MGMT_DOMAIN:
+ tlvi = proto_tree_add_text(cdp_tree, tvb,
+ offset, length, "VTP Management Domain: %.*s",
+ length - 4,
+ tvb_get_ptr(tvb, offset + 4, length - 4));
+ tlv_tree = proto_item_add_subtree(tlvi, ett_cdp_tlv);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvtype, tvb,
+ offset + TLV_TYPE, 2, type);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvlength, tvb,
+ offset + TLV_LENGTH, 2, length);
+ proto_tree_add_text(tlv_tree, tvb, offset + 4,
+ length - 4, "VTP Management Domain: %.*s",
+ length - 4,
+ tvb_get_ptr(tvb, offset + 4, length - 4));
+ offset += length;
+ break;
+ case TYPE_NATIVE_VLAN:
+ tlvi = proto_tree_add_text(cdp_tree, tvb,
+ offset, length, "Native VLAN: %u",
+ tvb_get_ntohs(tvb, offset + 4));
+ tlv_tree = proto_item_add_subtree(tlvi, ett_cdp_tlv);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvtype, tvb,
+ offset + TLV_TYPE, 2, type);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvlength, tvb,
+ offset + TLV_LENGTH, 2, length);
+ proto_tree_add_text(tlv_tree, tvb, offset + 4,
+ length - 4, "Native VLAN: %u",
+ tvb_get_ntohs(tvb, offset + 4));
+ offset += length;
+ break;
+ case TYPE_DUPLEX:
+ tlvi = proto_tree_add_text(cdp_tree, tvb,
+ offset, length, "Duplex: %s",
+ tvb_get_guint8(tvb, offset + 4) ?
+ "Full" : "Half" );
+ tlv_tree = proto_item_add_subtree(tlvi, ett_cdp_tlv);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvtype, tvb,
+ offset + TLV_TYPE, 2, type);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvlength, tvb,
+ offset + TLV_LENGTH, 2, length);
+ proto_tree_add_text(tlv_tree, tvb, offset + 4,
+ length - 4, "Duplex: %s",
+ tvb_get_guint8(tvb, offset + 4) ?
+ "Full" : "Half" );
+ offset += length;
+ break;
+ default:
+ tlvi = proto_tree_add_text(cdp_tree, tvb, offset,
+ length, "Type: %s, length: %u",
+ val_to_str(type, type_vals, "Unknown (0x%04x)"),
+ length);
+ tlv_tree = proto_item_add_subtree(tlvi, ett_cdp_tlv);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvtype, tvb,
+ offset + TLV_TYPE, 2, type);
+ proto_tree_add_uint(tlv_tree, hf_cdp_tlvlength, tvb,
+ offset + TLV_LENGTH, 2, length);
+ if (length > 4) {
+ proto_tree_add_text(tlv_tree, tvb, offset + 4,
+ length - 4, "Data");
+ } else
+ return;
+ offset += length;
+ }
}
+ call_dissector(data_handle, tvb_new_subset(tvb, offset, -1, -1), pinfo,
+ cdp_tree);
+ }
}
+#define PROTO_TYPE_NLPID 1
+#define PROTO_TYPE_IEEE_802_2 2
+
+static const value_string proto_type_vals[] = {
+ { PROTO_TYPE_NLPID, "NLPID" },
+ { PROTO_TYPE_IEEE_802_2, "802.2" },
+ { 0, NULL },
+};
+
+static int
+dissect_address_tlv(tvbuff_t *tvb, int offset, int length, proto_tree *tree)
+{
+ proto_item *ti;
+ proto_tree *address_tree;
+ guint8 protocol_type;
+ guint8 protocol_length;
+ int nlpid;
+ char *protocol_str;
+ guint16 address_length;
+ char *address_type_str;
+ char *address_str;
+
+ if (length < 1)
+ return -1;
+ ti = proto_tree_add_text(tree, tvb, offset, length, "Truncated address");
+ address_tree = proto_item_add_subtree(ti, ett_cdp_address);
+ protocol_type = tvb_get_guint8(tvb, offset);
+ proto_tree_add_text(address_tree, tvb, offset, 1, "Protocol type: %s",
+ val_to_str(protocol_type, proto_type_vals, "Unknown (0x%02x)"));
+ offset += 1;
+ length -= 1;
+
+ if (length < 1)
+ return -1;
+ protocol_length = tvb_get_guint8(tvb, offset);
+ proto_tree_add_text(address_tree, tvb, offset, 1, "Protocol length: %u",
+ protocol_length);
+ offset += 1;
+ length -= 1;
+
+ if (length < protocol_length) {
+ if (length != 0) {
+ proto_tree_add_text(address_tree, tvb, offset, length,
+ "Protocol: %s (truncated)",
+ tvb_bytes_to_str(tvb, offset, length));
+ }
+ return -1;
+ }
+ protocol_str = NULL;
+ if (protocol_type == PROTO_TYPE_NLPID && protocol_length == 1) {
+ nlpid = tvb_get_guint8(tvb, offset);
+ protocol_str = val_to_str(nlpid, nlpid_vals, "Unknown (0x%02x)");
+ } else
+ nlpid = -1;
+ if (protocol_str == NULL)
+ protocol_str = tvb_bytes_to_str(tvb, offset, protocol_length);
+ proto_tree_add_text(address_tree, tvb, offset, protocol_length,
+ "Protocol: %s", protocol_str);
+ offset += protocol_length;
+ length -= protocol_length;
+
+ if (length < 2)
+ return -1;
+ address_length = tvb_get_ntohs(tvb, offset);
+ proto_tree_add_text(address_tree, tvb, offset, 2, "Address length: %u",
+ address_length);
+ offset += 2;
+ length -= 2;
+
+ if (length < address_length) {
+ if (length != 0) {
+ proto_tree_add_text(address_tree, tvb, offset, length,
+ "Address: %s (truncated)",
+ tvb_bytes_to_str(tvb, offset, length));
+ }
+ return -1;
+ }
+ /* XXX - the Cisco document seems to be saying that, for 802.2-format
+ protocol types, 0xAAAA03 0x000000 0x0800 is IPv6, but 0x0800 is
+ the Ethernet protocol type for IPv4. */
+ length = 2 + protocol_length + 2 + address_length;
+ address_type_str = NULL;
+ address_str = NULL;
+ if (protocol_type == PROTO_TYPE_NLPID && protocol_length == 1) {
+ switch (nlpid) {
+
+ /* XXX - dissect NLPID_ISO8473_CLNP as OSI CLNP address? */
+
+ case NLPID_IP:
+ if (address_length == 4) {
+ /* The address is an IP address. */
+ address_type_str = "IP address";
+ address_str = ip_to_str(tvb_get_ptr(tvb, offset, 4));
+ }
+ break;
+ }
+ }
+ if (address_type_str == NULL)
+ address_type_str = "Address";
+ if (address_str == NULL) {
+ address_str = tvb_bytes_to_str(tvb, offset, address_length);
+ }
+ proto_item_set_text(ti, "%s: %s", address_type_str, address_str);
+ proto_tree_add_text(address_tree, tvb, offset, address_length, "%s: %s",
+ address_type_str, address_str);
+ return 2 + protocol_length + 2 + address_length;
+}
+
+static void
+dissect_capabilities(tvbuff_t *tvb, int offset, int length, proto_tree *tree)
+{
+ proto_item *ti;
+ proto_tree *capabilities_tree;
+ guint32 capabilities;
+
+ if (length < 4)
+ return;
+ capabilities = tvb_get_ntohl(tvb, offset);
+ ti = proto_tree_add_text(tree, tvb, offset, length, "Capabilities: 0x%08x",
+ capabilities);
+ capabilities_tree = proto_item_add_subtree(ti, ett_cdp_capabilities);
+ proto_tree_add_text(capabilities_tree, tvb, offset, 4,
+ decode_boolean_bitfield(capabilities, 0x01, 4*8,
+ "Performs level 3 routing",
+ "Doesn't perform level 3 routing"));
+ proto_tree_add_text(capabilities_tree, tvb, offset, 4,
+ decode_boolean_bitfield(capabilities, 0x02, 4*8,
+ "Performs level 2 transparent bridging",
+ "Doesn't perform level 2 transparent bridging"));
+ proto_tree_add_text(capabilities_tree, tvb, offset, 4,
+ decode_boolean_bitfield(capabilities, 0x04, 4*8,
+ "Performs level 2 source-route bridging",
+ "Doesn't perform level 2 source-route bridging"));
+ proto_tree_add_text(capabilities_tree, tvb, offset, 4,
+ decode_boolean_bitfield(capabilities, 0x08, 4*8,
+ "Performs level 2 switching",
+ "Doesn't perform level 2 switching"));
+ proto_tree_add_text(capabilities_tree, tvb, offset, 4,
+ decode_boolean_bitfield(capabilities, 0x10, 4*8,
+ "Sends and receives packets for network-layer protocols",
+ "Doesn't send or receive packets for network-layer protocols"));
+ proto_tree_add_text(capabilities_tree, tvb, offset, 4,
+ decode_boolean_bitfield(capabilities, 0x20, 4*8,
+ "Doesn't forward IGMP Report packets on nonrouter ports",
+ "Forwards IGMP Report packets on nonrouter ports"));
+ proto_tree_add_text(capabilities_tree, tvb, offset, 4,
+ decode_boolean_bitfield(capabilities, 0x40, 4*8,
+ "Provides level 1 functionality",
+ "Doesn't provide level 1 functionality"));
+}
+
+static void
+add_multi_line_string_to_tree(proto_tree *tree, tvbuff_t *tvb, gint start,
+ gint len, const gchar *prefix)
+{
+ int prefix_len;
+ int i;
+ char blanks[64+1];
+ gint next;
+ 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';
+ while (len > 0) {
+ line_len = tvb_find_line_end(tvb, start, len, &next, FALSE);
+ data_len = next - start;
+ proto_tree_add_text(tree, tvb, start, data_len, "%s%.*s", prefix,
+ line_len, tvb_get_ptr(tvb, start, line_len));
+ start += data_len;
+ len -= 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,
+ "", HFILL }},
+
+ { &hf_cdp_ttl,
+ { "TTL", "cdp.ttl", FT_UINT16, BASE_DEC, NULL, 0x0,
+ "", HFILL }},
+
+ { &hf_cdp_checksum,
+ { "Checksum", "cdp.checksum", FT_UINT16, BASE_HEX, NULL, 0x0,
+ "", HFILL }},
+
+ { &hf_cdp_tlvtype,
+ { "Type", "cdp.tlv.type", FT_UINT16, BASE_HEX, VALS(type_vals), 0x0,
+ "", HFILL }},
+
+ { &hf_cdp_tlvlength,
+ { "Length", "cdp.tlv.len", FT_UINT16, BASE_DEC, NULL, 0x0,
+ "", HFILL }},
+ };
+ static gint *ett[] = {
+ &ett_cdp,
+ &ett_cdp_tlv,
+ &ett_cdp_address,
+ &ett_cdp_capabilities,
+ };
+
+ proto_cdp = proto_register_protocol("Cisco Discovery Protocol",
+ "CDP", "cdp");
+ proto_register_field_array(proto_cdp, hf, array_length(hf));
+ proto_register_subtree_array(ett, array_length(ett));
+}
+
+void
+proto_reg_handoff_cdp(void)
+{
+ dissector_handle_t cdp_handle;
+
+ data_handle = find_dissector("data");
+ cdp_handle = create_dissector_handle(dissect_cdp, proto_cdp);
+ dissector_add("llc.cisco_pid", 0x2000, cdp_handle);
+ dissector_add("chdlctype", 0x2000, cdp_handle);
+ dissector_add("ppp.protocol", 0x0207, cdp_handle);
+}