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wireshark/epan/dissectors/packet-nhrp.c

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/* packet-nhrp.c
* Routines for NBMA Next Hop Resoultion Protocol
*
* $Id$
*
* 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
*
*
* CIE decoding for extensions and Cisco 12.4T extensions
* added by Timo Teras <timo.teras@iki.fi>
*
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <glib.h>
#include <epan/packet.h>
#include <epan/addr_resolv.h>
#include <epan/etypes.h>
#include <epan/ipproto.h>
#include <epan/greproto.h>
#include <epan/sminmpec.h>
#include <epan/in_cksum.h>
#include "packet-nhrp.h"
/* forward reference */
void proto_register_nhrp(void);
void proto_reg_handoff_nhrp(void);
void dissect_nhrp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
static int proto_nhrp = -1;
static int hf_nhrp_hdr_afn = -1;
static int hf_nhrp_hdr_pro_type = -1;
static int hf_nhrp_hdr_pro_snap = -1;
static int hf_nhrp_hdr_hopcnt = -1;
static int hf_nhrp_hdr_pktsz = -1;
static int hf_nhrp_hdr_chksum = -1;
static int hf_nhrp_hdr_extoff = -1;
static int hf_nhrp_hdr_version = -1;
static int hf_nhrp_hdr_op_type = -1;
static int hf_nhrp_hdr_shtl = -1;
static int hf_nhrp_hdr_sstl = -1;
static int hf_nhrp_src_proto_len = -1;
static int hf_nhrp_dst_proto_len = -1;
static int hf_nhrp_flags = -1;
static int hf_nhrp_flag_Q = -1;
static int hf_nhrp_flag_N = -1;
static int hf_nhrp_flag_A = -1;
static int hf_nhrp_flag_D = -1;
static int hf_nhrp_flag_U1 = -1;
static int hf_nhrp_flag_U2 = -1;
static int hf_nhrp_flag_S = -1;
static int hf_nhrp_flag_NAT = -1;
static int hf_nhrp_src_nbma_addr = -1;
static int hf_nhrp_src_nbma_saddr = -1;
static int hf_nhrp_src_prot_addr = -1;
static int hf_nhrp_dst_prot_addr = -1;
static int hf_nhrp_request_id = -1;
static int hf_nhrp_code = -1;
static int hf_nhrp_prefix_len = -1;
static int hf_nhrp_unused = -1;
static int hf_nhrp_mtu = -1;
static int hf_nhrp_holding_time = -1;
static int hf_nhrp_cli_addr_tl = -1;
static int hf_nhrp_cli_saddr_tl = -1;
static int hf_nhrp_cli_prot_len = -1;
static int hf_nhrp_pref = -1;
static int hf_nhrp_client_nbma_addr = -1;
static int hf_nhrp_client_nbma_saddr = -1;
static int hf_nhrp_client_prot_addr = -1;
static int hf_nhrp_ext_C = -1;
static int hf_nhrp_ext_type = -1;
static int hf_nhrp_ext_len = -1;
static int hf_nhrp_ext_value = -1;
static int hf_nhrp_error_offset = -1;
static int hf_nhrp_error_packet = -1;
static gint ett_nhrp = -1;
static gint ett_nhrp_hdr = -1;
static gint ett_nhrp_mand = -1;
static gint ett_nhrp_ext = -1;
static gint ett_nhrp_mand_flag = -1;
static gint ett_nhrp_cie = -1;
static gint ett_nhrp_indication = -1;
/* NHRP Packet Types */
#define NHRP_RESOLUTION_REQ 1
#define NHRP_RESOLUTION_REPLY 2
#define NHRP_REGISTRATION_REQ 3
#define NHRP_REGISTRATION_REPLY 4
#define NHRP_PURGE_REQ 5
#define NHRP_PURGE_REPLY 6
#define NHRP_ERROR_INDICATION 7
#define NHRP_TRAFFIC_INDICATION 8
/* NHRP Extension Types */
#define NHRP_EXT_NULL 0 /* End of Extension */
#define NHRP_EXT_RESP_ADDR 3 /* Responder Address Extension */
#define NHRP_EXT_FWD_RECORD 4 /* NHRP Forward Transit NHS Record Extension */
#define NHRP_EXT_REV_RECORD 5 /* NHRP Reverse Transit NHS Record Extension */
#define NHRP_EXT_AUTH 7 /* NHRP Authentication Extension */
#define NHRP_EXT_VENDOR_PRIV 8 /* NHRP Vendor Private Extension */
#define NHRP_EXT_NAT_ADDRESS 9 /* Cisco NAT Address Extension */
/* NHRP Error Codes */
#define NHRP_ERR_UNRECOGNIZED_EXT 0x0001
#define NHRP_ERR_NHRP_LOOP_DETECT 0x0003
#define NHRP_ERR_PROT_ADDR_UNREACHABLE 0x0006
#define NHRP_ERR_PROT_ERROR 0x0007
#define NHRP_ERR_SDU_SIZE_EXCEEDED 0x0008
#define NHRP_ERR_INV_EXT 0x0009
#define NHRP_ERR_INV_RESOLUTION_REPLY 0x000a
#define NHRP_ERR_AUTH_FAILURE 0x000b
#define NHRP_ERR_HOP_COUNT_EXCEEDED 0x000f
/* NHRP CIE codes */
#define NHRP_CODE_SUCCESS 0x00
#define NHRP_CODE_ADMIN_PROHIBITED 0x04
#define NHRP_CODE_INSUFFICIENT_RESOURCES 0x05
#define NHRP_CODE_NO_BINDING_EXISTS 0x0c
#define NHRP_CODE_NON_UNIQUE_BINDING 0x0e
static const value_string nhrp_op_type_vals[] = {
{ NHRP_RESOLUTION_REQ, "NHRP Resolution Request" },
{ NHRP_RESOLUTION_REPLY, "NHRP Resolution Reply" },
{ NHRP_REGISTRATION_REQ, "NHRP Registration Request" },
{ NHRP_REGISTRATION_REPLY, "NHRP Registration Reply" },
{ NHRP_PURGE_REQ, "NHRP Purge Request" },
{ NHRP_PURGE_REPLY, "NHRP Purge Reply" },
{ NHRP_ERROR_INDICATION, "NHRP Error Indication" },
{ NHRP_TRAFFIC_INDICATION, "NHRP Traffic Indication" },
{ 0, NULL }
};
static const value_string ext_type_vals[] = {
{ NHRP_EXT_NULL, "End of Extension" },
{ NHRP_EXT_RESP_ADDR, "Responder Address Extension" },
{ NHRP_EXT_FWD_RECORD, "Forward Transit NHS Record Extension" },
{ NHRP_EXT_REV_RECORD, "Reverse Transit NHS Record Extension" },
{ NHRP_EXT_AUTH, "NHRP Authentication Extension" },
{ NHRP_EXT_VENDOR_PRIV, "NHRP Vendor Private Extension" },
{ NHRP_EXT_NAT_ADDRESS, "Cisco NAT Address Extension" },
{ 0, NULL }
};
static const value_string nhrp_error_code_vals[] = {
{ NHRP_ERR_UNRECOGNIZED_EXT, "Unrecognized Extension" },
{ NHRP_ERR_NHRP_LOOP_DETECT, "NHRP Loop Detected" },
{ NHRP_ERR_PROT_ADDR_UNREACHABLE, "Protocol Address Unreachable" },
{ NHRP_ERR_PROT_ERROR, "Protocol Error" },
{ NHRP_ERR_SDU_SIZE_EXCEEDED, "NHRP SDU Size Exceeded" },
{ NHRP_ERR_INV_EXT, "Invalid Extension" },
{ NHRP_ERR_INV_RESOLUTION_REPLY, "Invalid NHRP Reolution Reply Received" },
{ NHRP_ERR_AUTH_FAILURE, "Authentication Failure" },
{ NHRP_ERR_HOP_COUNT_EXCEEDED, "Hop Count Exceeded" },
{ 0, NULL }
};
static const value_string nhrp_cie_code_vals[] = {
{ NHRP_CODE_SUCCESS, "Success" },
{ NHRP_CODE_ADMIN_PROHIBITED, "Administratively Prohibited" },
{ NHRP_CODE_INSUFFICIENT_RESOURCES, "Insufficient Resources" },
{ NHRP_CODE_NO_BINDING_EXISTS, "No Interworking Layer Address to NBMA Address Binding Exists" },
{ NHRP_CODE_NON_UNIQUE_BINDING, "Binding Exists But Is Not Unique" },
{ 0, NULL }
};
static guint16 nhrp_checksum(const guint8 *ptr, int len)
{
vec_t cksum_vec[1];
cksum_vec[0].ptr = ptr;
cksum_vec[0].len = len;
return in_cksum(&cksum_vec[0], 1);
}
void dissect_nhrp_hdr(tvbuff_t *tvb,
proto_tree *tree,
gint *pOffset,
gint *pMandLen,
gint *pExtLen,
e_nhrp_hdr *hdr)
{
gint offset = *pOffset;
gchar *pro_type_str = "";
gint total_len = tvb_length(tvb);
guint16 ipcsum, rx_chksum;
proto_item *nhrp_tree_item = NULL;
proto_tree *nhrp_tree = NULL;
nhrp_tree_item = proto_tree_add_text(tree, tvb, offset, 20, "NHRP Fixed Header");
nhrp_tree = proto_item_add_subtree(nhrp_tree_item, ett_nhrp_hdr);
hdr->ar_pktsz = tvb_get_ntohs(tvb, 10);
if (total_len > hdr->ar_pktsz) {
total_len = hdr->ar_pktsz;
}
ipcsum = nhrp_checksum(tvb_get_ptr(tvb, offset, total_len), total_len);
hdr->ar_afn = tvb_get_ntohs(tvb, offset);
proto_tree_add_item(nhrp_tree, hf_nhrp_hdr_afn, tvb, offset, 2, FALSE);
offset += 2;
hdr->ar_pro_type = tvb_get_ntohs(tvb, offset);
switch (hdr->ar_pro_type) {
case ETHERTYPE_IP:
pro_type_str = "IPv4";
break;
case ETHERTYPE_IPv6:
pro_type_str = "IPv6";
break;
default:
pro_type_str = "Unknown";
break;
}
proto_tree_add_uint_format(nhrp_tree, hf_nhrp_hdr_pro_type, tvb, offset, 2,
hdr->ar_pro_type,
"Protocol Type (short form): %#x (%s)",
hdr->ar_pro_type, pro_type_str);
offset += 2;
proto_tree_add_text(nhrp_tree, tvb, offset, 5,
"Protocol Type (long form): %s",
tvb_bytes_to_str(tvb, offset, 5));
offset += 5;
proto_tree_add_item(nhrp_tree, hf_nhrp_hdr_hopcnt, tvb, offset, 1, FALSE);
offset += 1;
proto_tree_add_item(nhrp_tree, hf_nhrp_hdr_pktsz, tvb, offset, 2, FALSE);
offset += 2;
rx_chksum = tvb_get_ntohs(tvb, offset);
if (ipcsum == 0) {
proto_tree_add_uint_format(nhrp_tree, hf_nhrp_hdr_chksum, tvb, offset, 2, rx_chksum,
"NHRP Packet checksum: 0x%04x [correct]", rx_chksum);
} else {
proto_tree_add_uint_format(nhrp_tree, hf_nhrp_hdr_chksum, tvb, offset, 2, rx_chksum,
"NHRP Packet checksum: 0x%04x [incorrect, should be 0x%04x]", rx_chksum,
in_cksum_shouldbe(rx_chksum, ipcsum));
}
offset += 2;
hdr->ar_extoff = tvb_get_ntohs(tvb, offset);
proto_tree_add_item(nhrp_tree, hf_nhrp_hdr_extoff, tvb, offset, 2, FALSE);
offset += 2;
hdr->ar_op_version = tvb_get_guint8(tvb, offset);
proto_tree_add_text(nhrp_tree, tvb, offset, 1, "Version : %u (%s)",
hdr->ar_op_version,
(hdr->ar_op_version == 1) ? "NHRP - rfc2332" : "Unknown");
offset += 1;
proto_tree_add_text(nhrp_tree, tvb, offset, 1, "NHRP Packet Type : (%s)",
val_to_str(hdr->ar_op_type, nhrp_op_type_vals, "Unknown (%u)")) ;
offset += 1;
hdr->ar_shtl = tvb_get_guint8(tvb, offset);
proto_tree_add_item(nhrp_tree, hf_nhrp_hdr_shtl, tvb, offset, 1, FALSE);
offset += 1;
hdr->ar_sstl = tvb_get_guint8(tvb, offset);
proto_tree_add_item(nhrp_tree, hf_nhrp_hdr_sstl, tvb, offset, 1, FALSE);
offset += 1;
*pOffset = offset;
if (hdr->ar_extoff) {
*pMandLen = hdr->ar_extoff - 20;
*pExtLen = total_len - hdr->ar_extoff;
}
else {
*pMandLen = total_len - 20;
*pExtLen = 0;
}
}
void dissect_cie_list(tvbuff_t *tvb,
proto_tree *tree,
gint offset,
gint cieEnd,
gint isReq)
{
guint32 addr;
while ((offset + 12) <= cieEnd) {
gint cli_addr_len = tvb_get_guint8(tvb, offset + 8);
gint cli_saddr_len = tvb_get_guint8(tvb, offset + 9);
gint cli_prot_len = tvb_get_guint8(tvb, offset + 10);
gint cie_len = 12 + cli_addr_len + cli_saddr_len + cli_prot_len;
proto_item *cie_tree_item = proto_tree_add_text(tree, tvb, offset, cie_len, "Client Information Element");
proto_tree *cie_tree = proto_item_add_subtree(cie_tree_item, ett_nhrp_cie);
if (isReq) {
proto_tree_add_item(cie_tree, hf_nhrp_code, tvb, offset, 1, FALSE);
}
else {
guint8 code = tvb_get_guint8(tvb, offset);
proto_tree_add_text(cie_tree, tvb, offset, 1, "Code: %s",
val_to_str(code, nhrp_cie_code_vals, "Unknown (%u)"));
}
offset += 1;
proto_tree_add_item(cie_tree, hf_nhrp_prefix_len, tvb, offset, 1, FALSE);
offset += 1;
proto_tree_add_item(cie_tree, hf_nhrp_unused, tvb, offset, 2, FALSE);
offset += 2;
proto_tree_add_item(cie_tree, hf_nhrp_mtu, tvb, offset, 2, FALSE);
offset += 2;
proto_tree_add_item(cie_tree, hf_nhrp_holding_time, tvb, offset, 2, FALSE);
offset += 2;
proto_tree_add_item(cie_tree, hf_nhrp_cli_addr_tl, tvb, offset, 1, FALSE);
offset += 1;
proto_tree_add_item(cie_tree, hf_nhrp_cli_saddr_tl, tvb, offset, 1, FALSE);
offset += 1;
proto_tree_add_item(cie_tree, hf_nhrp_cli_prot_len, tvb, offset, 1, FALSE);
offset += 1;
proto_tree_add_item(cie_tree, hf_nhrp_pref, tvb, offset, 1, FALSE);
offset += 1;
if (cli_addr_len) {
tvb_ensure_bytes_exist(tvb, offset, cli_addr_len);
if (cli_addr_len == 4) {
addr = tvb_get_ipv4(tvb, offset);
proto_tree_add_ipv4(cie_tree, hf_nhrp_client_nbma_addr, tvb, offset, 4, addr);
}
else {
proto_tree_add_text(cie_tree, tvb, offset, cli_addr_len,
"Client NBMA Address: %s",
tvb_bytes_to_str(tvb, offset, cli_addr_len));
}
offset += cli_addr_len;
}
if (cli_saddr_len) {
tvb_ensure_bytes_exist(tvb, offset, cli_saddr_len);
proto_tree_add_text(cie_tree, tvb, offset, cli_saddr_len,
"Client NBMA Sub Address: %s",
tvb_bytes_to_str(tvb, offset, cli_saddr_len));
}
if (cli_prot_len) {
tvb_ensure_bytes_exist(tvb, offset, cli_prot_len);
if (cli_prot_len == 4) {
addr = tvb_get_ipv4(tvb, offset);
proto_tree_add_ipv4(cie_tree, hf_nhrp_client_prot_addr, tvb, offset, 4, addr);
}
else {
proto_tree_add_text(cie_tree, tvb, offset, cli_prot_len,
"Client Protocol Address: %s",
tvb_bytes_to_str(tvb, offset, cli_prot_len));
}
offset += cli_prot_len;
}
}
}
void dissect_nhrp_mand(tvbuff_t *tvb,
packet_info *pinfo,
proto_tree *tree,
gint *pOffset,
e_nhrp_hdr *hdr,
gint mandLen)
{
gint offset = *pOffset;
gint mandEnd = offset + mandLen;
guint32 addr;
guint8 ssl, shl;
guint16 flags;
guint srcLen, dstLen;
gboolean isReq = 0;
gboolean isErr = 0;
gboolean isInd = 0;
proto_item *nhrp_tree_item = NULL;
proto_item *flag_item = NULL;
proto_tree *nhrp_tree = NULL;
proto_tree *flag_tree = NULL;
tvb_ensure_bytes_exist(tvb, offset, mandLen);
switch (hdr->ar_op_type)
{
case NHRP_RESOLUTION_REQ:
case NHRP_REGISTRATION_REQ:
case NHRP_PURGE_REQ:
isReq = 1;
break;
case NHRP_ERROR_INDICATION: /* This needs special treatment */
isErr = 1;
isInd = 1;
break;
case NHRP_TRAFFIC_INDICATION:
isInd = 1;
break;
}
nhrp_tree_item = proto_tree_add_text(tree, tvb, offset, mandLen, "NHRP Mandatory Part");
nhrp_tree = proto_item_add_subtree(nhrp_tree_item, ett_nhrp_mand);
srcLen = tvb_get_guint8(tvb, offset);
proto_tree_add_item(nhrp_tree, hf_nhrp_src_proto_len, tvb, offset, 1, FALSE);
offset += 1;
dstLen = tvb_get_guint8(tvb, offset);
proto_tree_add_item(nhrp_tree, hf_nhrp_dst_proto_len, tvb, offset, 1, FALSE);
offset += 1;
if (!isInd) {
flags = tvb_get_ntohs(tvb, offset);
flag_item = proto_tree_add_uint(nhrp_tree, hf_nhrp_flags, tvb, offset, 2, flags);
flag_tree = proto_item_add_subtree(flag_item, ett_nhrp_mand_flag);
switch (hdr->ar_op_type)
{
case NHRP_RESOLUTION_REQ:
case NHRP_RESOLUTION_REPLY:
proto_tree_add_boolean(flag_tree, hf_nhrp_flag_Q, tvb, offset, 2, flags);
proto_tree_add_boolean(flag_tree, hf_nhrp_flag_A, tvb, offset, 2, flags);
proto_tree_add_boolean(flag_tree, hf_nhrp_flag_D, tvb, offset, 2, flags);
proto_tree_add_boolean(flag_tree, hf_nhrp_flag_U1, tvb, offset, 2, flags);
proto_tree_add_boolean(flag_tree, hf_nhrp_flag_S, tvb, offset, 2, flags);
break;
case NHRP_REGISTRATION_REQ:
case NHRP_REGISTRATION_REPLY:
proto_tree_add_boolean(flag_tree, hf_nhrp_flag_U2, tvb, offset, 2, flags);
break;
case NHRP_PURGE_REQ:
case NHRP_PURGE_REPLY:
proto_tree_add_boolean(flag_tree, hf_nhrp_flag_N, tvb, offset, 2, flags);
break;
}
proto_tree_add_boolean(flag_tree, hf_nhrp_flag_NAT, tvb, offset, 2, flags);
offset += 2;
proto_tree_add_item(nhrp_tree, hf_nhrp_request_id, tvb, offset, 4, FALSE);
offset += 4;
}
else if (isErr) {
guint16 err_code;
offset += 2;
err_code = tvb_get_ntohs(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 2, "Error Code: %s",
val_to_str(err_code, nhrp_error_code_vals, "Unknown (%u)"));
offset += 2;
proto_tree_add_item(nhrp_tree, hf_nhrp_error_offset, tvb, offset, 2, FALSE);
offset += 2;
}
else {
offset += 6;
}
/* TBD : Check for hdr->afn */
shl = hdr->ar_shtl & 0x3f;
if (shl) {
tvb_ensure_bytes_exist(tvb, offset, shl);
if (shl == 4) {
addr = tvb_get_ipv4(tvb, offset);
proto_tree_add_ipv4(nhrp_tree, hf_nhrp_src_nbma_addr, tvb, offset, 4, addr);
}
else {
proto_tree_add_text(nhrp_tree, tvb, offset, shl,
"Source NBMA Address: %s",
tvb_bytes_to_str(tvb, offset, shl));
}
offset += shl;
}
ssl = hdr->ar_sstl & 0x3f;
if (ssl) {
tvb_ensure_bytes_exist(tvb, offset, ssl);
proto_tree_add_text(nhrp_tree, tvb, offset, ssl,
"Source NBMA Sub Address: %s",
tvb_bytes_to_str(tvb, offset, ssl));
offset += ssl;
}
if (srcLen) {
if (srcLen == 4) {
addr = tvb_get_ipv4(tvb, offset);
proto_tree_add_ipv4(nhrp_tree, hf_nhrp_src_prot_addr, tvb, offset, 4, addr);
}
else {
proto_tree_add_text(nhrp_tree, tvb, offset, srcLen,
"Source Protocol Address: %s",
tvb_bytes_to_str(tvb, offset, srcLen));
}
offset += srcLen;
}
if (dstLen) {
if (dstLen == 4) {
addr = tvb_get_ipv4(tvb, offset);
proto_tree_add_ipv4(nhrp_tree, hf_nhrp_dst_prot_addr, tvb, offset, 4, addr);
}
else {
proto_tree_add_text(nhrp_tree, tvb, offset, dstLen,
"Destination Protocol Address: %s",
tvb_bytes_to_str(tvb, offset, dstLen));
}
offset += dstLen;
}
if (isInd) {
gint pkt_len = mandEnd - offset;
proto_item *ind_tree_item = proto_tree_add_text(tree, tvb, offset, pkt_len, "Packet Causing Indication");
proto_tree *ind_tree = proto_item_add_subtree(ind_tree_item, ett_nhrp_indication);
if (isErr) {
tvbuff_t *sub_tvb;
sub_tvb = tvb_new_subset(tvb, offset, -1, -1);
dissect_nhrp(sub_tvb, pinfo, ind_tree);
}
else {
ethertype(hdr->ar_pro_type, tvb, offset, pinfo, ind_tree, NULL, -1, -1, 0);
}
offset = mandEnd;
}
dissect_cie_list(tvb, nhrp_tree, offset, mandEnd, isReq);
*pOffset = mandEnd;
}
/* TBD : Decode Authentication Extension and Vendor Specific Extension */
void dissect_nhrp_ext(tvbuff_t *tvb,
proto_tree *tree,
gint *pOffset,
gint extLen)
{
gint offset = *pOffset;
gint extEnd = offset + extLen;
proto_item *nhrp_tree_item = NULL;
proto_tree *nhrp_tree = NULL;
tvb_ensure_bytes_exist(tvb, offset, extLen);
while ((offset + 4) <= extEnd)
{
gint extTypeC = tvb_get_ntohs(tvb, offset);
gint extType = extTypeC & 0x3FFF;
gint len = tvb_get_ntohs(tvb, offset+2);
nhrp_tree_item = proto_tree_add_text(tree, tvb, offset,
len + 4, "%s",
val_to_str(extType, ext_type_vals, "Unknown (%u)"));
nhrp_tree = proto_item_add_subtree(nhrp_tree_item, ett_nhrp_ext);
proto_tree_add_boolean(nhrp_tree, hf_nhrp_ext_C, tvb, offset, 2, extTypeC);
proto_tree_add_item(nhrp_tree, hf_nhrp_ext_type, tvb, offset, 2, FALSE);
offset += 2;
proto_tree_add_item(nhrp_tree, hf_nhrp_ext_len, tvb, offset, 2, FALSE);
offset += 2;
if (len) {
tvb_ensure_bytes_exist(tvb, offset, len);
switch (extType) {
case NHRP_EXT_RESP_ADDR:
case NHRP_EXT_FWD_RECORD:
case NHRP_EXT_REV_RECORD:
case NHRP_EXT_NAT_ADDRESS:
dissect_cie_list(tvb, nhrp_tree, offset, offset + len, 0);
break;
default:
proto_tree_add_text(nhrp_tree, tvb, offset, len,
"Extension Value: %s",
tvb_bytes_to_str(tvb, offset, len));
break;
}
offset += len;
}
}
*pOffset = extEnd;
}
void dissect_nhrp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
if (check_col(pinfo->cinfo, COL_PROTOCOL)) {
col_set_str(pinfo->cinfo, COL_PROTOCOL, "NHRP");
}
if (check_col(pinfo->cinfo, COL_INFO)) {
col_clear(pinfo->cinfo, COL_INFO);
}
if (tree) {
e_nhrp_hdr hdr;
gint mandLen = 0;
gint extLen = 0;
gint offset = 0;
proto_item *ti = NULL;
proto_tree *nhrp_tree = NULL;
/* Fixed header is always 20 bytes. */
tvb_ensure_bytes_exist(tvb, offset, 20);
memset(&hdr, 0, sizeof(e_nhrp_hdr));
hdr.ar_op_type = tvb_get_guint8(tvb, 17);
if (check_col(pinfo->cinfo, COL_INFO)) {
col_add_str(pinfo->cinfo, COL_INFO,
val_to_str(hdr.ar_op_type, nhrp_op_type_vals,
"0x%02X - unknown"));
}
col_set_writable(pinfo->cinfo, FALSE);
ti = proto_tree_add_protocol_format(tree, proto_nhrp, tvb, 0, -1,
"Next Hop Resolution Protocol (%s)",
val_to_str(hdr.ar_op_type,
nhrp_op_type_vals,
"0x%02X - unknown"));
nhrp_tree = proto_item_add_subtree(ti, ett_nhrp);
dissect_nhrp_hdr(tvb, nhrp_tree, &offset, &mandLen, &extLen, &hdr);
if (mandLen) {
dissect_nhrp_mand(tvb, pinfo, nhrp_tree, &offset, &hdr, mandLen);
}
if (extLen) {
dissect_nhrp_ext(tvb, nhrp_tree, &offset, extLen);
}
} /* End of if (tree) */
}
void
proto_register_nhrp(void)
{
static hf_register_info hf[] = {
{ &hf_nhrp_hdr_afn,
{ "Address Family Number", "nhrp.hdr.afn", FT_UINT16, BASE_HEX_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_hdr_pro_type,
{ "Protocol Type (short form)", "nhrp.hdr.pro.type",FT_UINT16, BASE_HEX_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_hdr_pro_snap,
{ "Protocol Type (long form)", "nhrp.hdr.pro.snap",FT_UINT_BYTES, BASE_HEX, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_hdr_hopcnt,
{ "Hop Count", "nhrp.hdr.hopcnt", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_hdr_pktsz,
{ "Packet Length", "nhrp.hdr.pktsz", FT_UINT16, BASE_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_hdr_chksum,
{ "Packet Checksum", "nhrp.hdr.chksum", FT_UINT16, BASE_HEX, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_hdr_extoff,
{ "Extension Offset", "nhrp.hdr.extoff", FT_UINT16, BASE_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_hdr_version,
{ "Version", "nhrp.hdr.version", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_hdr_op_type,
{ "NHRP Packet Type", "nhrp.hdr.op.type", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_hdr_shtl,
{ "Source Address Type/Len", "nhrp.hdr.shtl", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_hdr_sstl,
{ "Source SubAddress Type/Len", "nhrp.hdr.sstl", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_src_proto_len,
{ "Source Protocol Len", "nhrp.src.prot.len",FT_UINT16, BASE_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_dst_proto_len,
{ "Destination Protocol Len", "nhrp.dst.prot.len",FT_UINT16, BASE_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_flags,
{ "Flags", "nhrp.flags", FT_UINT16, BASE_HEX, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_flag_Q,
{ "Is Router", "nhrp.flag.q", FT_BOOLEAN, 16, NULL, 0x8000, "", HFILL }},
{ &hf_nhrp_flag_N,
{ "Expected Purge Reply", "nhrp.flag.n", FT_BOOLEAN, 16, NULL, 0x8000, "", HFILL }},
{ &hf_nhrp_flag_A,
{ "Authoritative", "nhrp.flag.a", FT_BOOLEAN, 16, NULL, 0x4000, "A bit", HFILL }},
{ &hf_nhrp_flag_D,
{ "Stable Association", "nhrp.flag.d", FT_BOOLEAN, 16, NULL, 0x2000, "D bit", HFILL }},
{ &hf_nhrp_flag_U1,
{ "Uniqueness Bit", "nhrp.flag.u1", FT_BOOLEAN, 16, NULL, 0x1000, "U bit", HFILL }},
{ &hf_nhrp_flag_U2,
{ "Uniqueness Bit", "nhrp.flag.u1", FT_BOOLEAN, 16, NULL, 0x8000, "U bit", HFILL }},
{ &hf_nhrp_flag_S,
{ "Stable Binding", "nhrp.flag.s", FT_BOOLEAN, 16, NULL, 0x0800, "S bit", HFILL }},
{ &hf_nhrp_flag_NAT,
{ "Cisco NAT Supported", "nhrp.flag.nat", FT_BOOLEAN, 16, NULL, 0x0002, "NAT bit", HFILL }},
{ &hf_nhrp_request_id,
{ "Request ID", "nhrp.reqid", FT_UINT32, BASE_HEX_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_src_nbma_addr,
{ "Source NBMA Address", "nhrp.src.nbma.addr",FT_IPv4, BASE_NONE, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_src_nbma_saddr,
{ "Source NBMA Sub Address", "nhrp.src.nbma.saddr",FT_UINT_BYTES,BASE_HEX, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_src_prot_addr,
{ "Source Protocol Address", "nhrp.src.prot.addr",FT_IPv4, BASE_NONE, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_dst_prot_addr,
{ "Destination Protocol Address", "nhrp.dst.prot.addr",FT_IPv4, BASE_NONE, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_code,
{ "Code", "nhrp.code", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_prefix_len,
{ "Prefix Length", "nhrp.prefix", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_unused,
{ "Unused", "nhrp.unused", FT_UINT16,BASE_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_mtu,
{ "Max Transmission Unit", "nhrp.mtu", FT_UINT16,BASE_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_holding_time,
{ "Holding Time (s)", "nhrp.htime", FT_UINT16,BASE_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_cli_addr_tl,
{ "Client Address Type/Len", "nhrp.cli.addr.tl", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_cli_saddr_tl,
{ "Client Sub Address Type/Len","nhrp.cli.saddr.tl", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_cli_prot_len,
{ "Client Protocol Length", "nhrp.prot.len", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_pref,
{ "CIE Preference Value", "nhrp.pref", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_client_nbma_addr,
{ "Client NBMA Address", "nhrp.client.nbma.addr", FT_IPv4, BASE_NONE, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_client_nbma_saddr,
{ "Client NBMA Sub Address", "nhrp.client.nbma.saddr",FT_UINT_BYTES, BASE_HEX, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_client_prot_addr,
{ "Client Protocol Address", "nhrp.client.prot.addr", FT_IPv4, BASE_NONE, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_ext_C,
{ "Compulsary Flag", "nhrp.ext.c", FT_BOOLEAN, 16, NULL, 0x8000, "", HFILL }},
{ &hf_nhrp_ext_type,
{ "Extension Type", "nhrp.ext.type", FT_UINT16, BASE_HEX, NULL, 0x3FFF, "", HFILL }},
{ &hf_nhrp_ext_len,
{ "Extension length", "nhrp.ext.len", FT_UINT16, BASE_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_ext_value,
{ "Extension Value", "nhrp.ext.val", FT_UINT_BYTES,BASE_HEX, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_error_offset,
{ "Error Offset", "nhrp.err.offset", FT_UINT16, BASE_DEC, NULL, 0x0, "", HFILL }},
{ &hf_nhrp_error_packet,
{ "Errored Packet", "nhrp.err.pkt", FT_UINT_BYTES,BASE_HEX, NULL, 0x0, "", HFILL }},
};
static gint *ett[] = {
&ett_nhrp,
&ett_nhrp_hdr,
&ett_nhrp_mand,
&ett_nhrp_ext,
&ett_nhrp_mand_flag,
&ett_nhrp_cie,
&ett_nhrp_indication
};
proto_nhrp = proto_register_protocol(
"NBMA Next Hop Resolution Protocol",
"NHRP",
"nhrp");
proto_register_field_array(proto_nhrp, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
}
void
proto_reg_handoff_nhrp(void)
{
dissector_handle_t nhrp_handle;
nhrp_handle = create_dissector_handle(dissect_nhrp, proto_nhrp);
dissector_add("ip.proto", IP_PROTO_NARP, nhrp_handle);
dissector_add("gre.proto", GRE_NHRP, nhrp_handle);
}
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