/* packet-nlsp.c

 * Routines for NetWare Link Services Protocol

 *

 * Based on ISIS dissector by Stuart Stanley <stuarts@mxmail.net>

 *

 * Wireshark - Network traffic analyzer

 * By Gerald Combs <gerald@wireshark.org>

 * Copyright 1998 Gerald Combs

 *

 * SPDX-License-Identifier: GPL-2.0-or-later

 */

#include "config.h"

#include <epan/packet.h>

#include <epan/expert.h>

#include <epan/to_str.h>

#include <epan/tfs.h>

#include <epan/unit_strings.h>

#include <wsutil/array.h>

#include "packet-ipx.h"

void proto_register_nlsp(void);

void proto_reg_handoff_nlsp(void);

static dissector_handle_t nlsp_handle;

/* NLSP base header */

static int proto_nlsp;

static int hf_nlsp_irpd;

static int hf_nlsp_header_length;

static int hf_nlsp_minor_version;

static int hf_nlsp_nr;

static int hf_nlsp_type;

static int hf_nlsp_major_version;

static int hf_nlsp_packet_length;

static int hf_nlsp_hello_state;

static int hf_nlsp_hello_multicast;

static int hf_nlsp_hello_circuit_type;

static int hf_nlsp_hello_holding_timer;

static int hf_nlsp_hello_priority;

static int hf_nlsp_lsp_sequence_number;

static int hf_nlsp_lsp_checksum;

static int hf_nlsp_lsp_p;

static int hf_nlsp_lsp_attached_flag;

static int hf_nlsp_lsp_lspdbol;

static int hf_nlsp_lsp_router_type;

static int hf_nlsp_lsp_link_info_clv_flags_cost_present;

static int hf_nlsp_lsp_link_info_clv_flags_cost_metric;

static int hf_nlsp_lsp_link_info_clv_flags_cost;

/* Generated from convert_proto_tree_add_text.pl */

static int hf_nlsp_psnp_lsp_checksum;

static int hf_nlsp_csnp_start_lsp_id_source_id;

static int hf_nlsp_svcs_info_node_number;

static int hf_nlsp_ext_routes_rip_delay;

static int hf_nlsp_psnp_source_id_system_id;

static int hf_nlsp_svcs_info_socket;

static int hf_nlsp_hello_sending_router_system_id;

static int hf_nlsp_csnp_start_lsp_id_lsp_number;

static int hf_nlsp_lsp_id_system_id;

static int hf_nlsp_psnp_lsp_id_pseudonode_id;

static int hf_nlsp_csnp_end_lsp_id_lsp_number;

static int hf_nlsp_remaining_lifetime;

static int hf_nlsp_csnp_remaining_lifetime;

static int hf_nlsp_psnp_lsp_id_source_id;

static int hf_nlsp_ext_routes_hops;

static int hf_nlsp_hello_local_mtu_mtu_size;

static int hf_nlsp_link_info_throughput;

static int hf_nlsp_link_info_media_type;

static int hf_nlsp_mgt_info_name;

static int hf_nlsp_mgt_info_node_number;

static int hf_nlsp_csnp_end_lsp_id_source_id;

static int hf_nlsp_csnp_lsp_id_pseudonode_id;

static int hf_nlsp_psnp_lsp_sequence_number;

static int hf_nlsp_link_info_mtu_size;

static int hf_nlsp_lsp_id_lsp_number;

static int hf_nlsp_unknown_code;

static int hf_nlsp_mgt_info_ipx_version_number;

static int hf_nlsp_link_info_router_pseudonode_id;

static int hf_nlsp_psnp_source_id_pseudonode_id;

static int hf_nlsp_csnp_lsp_id_lsp_number;

static int hf_nlsp_csnp_source_id_pseudonode_id;

static int hf_nlsp_csnp_end_lsp_id_pseudonode_id;

static int hf_nlsp_csnp_lsp_sequence_number;

static int hf_nlsp_link_info_router_system_id;

static int hf_nlsp_svcs_info_type;

static int hf_nlsp_csnp_lsp_checksum;

static int hf_nlsp_hello_local_wan_circuit_id;

static int hf_nlsp_svcs_info_service_name;

static int hf_nlsp_mgt_info_name_length;

static int hf_nlsp_neighbor;

static int hf_nlsp_area_address_network_number;

static int hf_nlsp_link_info_delay;

static int hf_nlsp_csnp_start_lsp_id_pseudonode_id;

static int hf_nlsp_svcs_info_network_number;

static int hf_nlsp_csnp_source_id_system_id;

static int hf_nlsp_mgt_info_network_number;

static int hf_nlsp_hello_designated_router_pseudonode_id;

static int hf_nlsp_lsp_id_pseudonode_id;

static int hf_nlsp_csnp_lsp_id_source_id;

static int hf_nlsp_psnp_remaining_lifetime;

static int hf_nlsp_area_address_mask;

static int hf_nlsp_hello_designated_router_system_id;

static int hf_nlsp_svcs_info_hops_to_reach_the_service;

static int hf_nlsp_psnp_lsp_id_lsp_number;

static int hf_nlsp_ext_routes_network_number;

static expert_field ei_nlsp_short_packet;

static expert_field ei_nlsp_long_packet;

static expert_field ei_nlsp_major_version;

static expert_field ei_nlsp_type;

static int ett_nlsp;

static int ett_nlsp_hello_clv_area_addr;

static int ett_nlsp_hello_clv_neighbors;

static int ett_nlsp_hello_local_mtu;

static int ett_nlsp_hello_clv_unknown;

static int ett_nlsp_lsp_info;

static int ett_nlsp_lsp_clv_area_addr;

static int ett_nlsp_lsp_clv_mgt_info;

static int ett_nlsp_lsp_clv_link_info;

static int ett_nlsp_lsp_clv_svcs_info;

static int ett_nlsp_lsp_clv_ext_routes;

static int ett_nlsp_lsp_clv_unknown;

static int ett_nlsp_csnp_lsp_entries;

static int ett_nlsp_csnp_lsp_entry;

static int ett_nlsp_csnp_clv_unknown;

static int ett_nlsp_psnp_lsp_entries;

static int ett_nlsp_psnp_lsp_entry;

static int ett_nlsp_psnp_clv_unknown;

#define PACKET_TYPE_MASK  0x1f

/*

 * See

 *

 *  http://www.cisco.com/univercd/cc/td/doc/cisintwk/ito_doc/nlsp.htm

 *

 * for some information about Hello packets.

 */

#define NLSP_TYPE_L1_HELLO  15

#define NLSP_TYPE_WAN_HELLO 17

#define NLSP_TYPE_L1_LSP  18

#define NLSP_TYPE_L1_CSNP 24

#define NLSP_TYPE_L1_PSNP 26

static const value_string nlsp_packet_type_vals[] = {

  { NLSP_TYPE_L1_HELLO,  "L1 Hello"},

  { NLSP_TYPE_WAN_HELLO, "WAN Hello"},

  { NLSP_TYPE_L1_LSP,    "L1 LSP"},

  { NLSP_TYPE_L1_CSNP,   "L1 CSNP"},

  { NLSP_TYPE_L1_PSNP,   "L1 PSNP"},

  { 0,                   NULL}

};

static const value_string nlsp_attached_flag_vals[] = {

  { 0, "Other routing areas cannot be reached through this router"},

  { 1, "Other routing areas can be reached through this router"},

  { 0, NULL}

};

static const value_string nlsp_router_type_vals[] = {

  { 1, "Level 1 Router"},

  { 3, "Level 1 and Level 2 Router"},

  { 0, NULL}

};

static const true_false_string tfs_internal_external = { "Internal", "External" };

/*

 * Our sub-packet dismantle structure for CLV's

 */

typedef struct {

  int   optcode;    /* code for option */

  const char  *tree_text;   /* text for fold out */

  int   *tree_id;   /* id for add_item */

  void    (*dissect)(tvbuff_t *tvb, packet_info* pinfo, proto_tree *tree,

        unsigned offset, unsigned length);

} nlsp_clv_handle_t;

/*

 * Name: nlsp_dissect_clvs()

 *

 * Description:

 *  Dispatch routine to shred all the CLVs in a packet.  We just

 *  walk through the clv entries in the packet.  For each one, we

 *  search the passed in valid clv's for this protocol (opts) for

 *  a matching code.  If found, we add to the display tree and

 *  then call the dissector.  If it is not, we just post an

 *  "unknown" clv entry using the passed in unknown clv tree id.

 *      XXX: The "unknown tree id" is an 'ett' index for use

 *           when creating a subtree;

 *           Since the 'unknown' subtree was not actually used in the

 *           code below, what was the intention for this ?

 *           For now: code related to creating an 'unknown' subtrree

 *            disabled.

 *

 * Input:

 *  tvbuff_t * : tvbuffer for packet data

 *  proto_tree * : protocol display tree to fill out.  May be NULL

 *  int : offset into packet data where we are.

 *  nlsp_clv_handle_t * : NULL dissector terminated array of codes

 *    and handlers (along with tree text and tree id's).

 *  int : length of CLV area.

 *  int : unknown clv tree id

 *

 * Output:

 *  void, but we will add to proto tree if !NULL.

 */

static void

nlsp_dissect_clvs(tvbuff_t *tvb, packet_info* pinfo, proto_tree *tree, unsigned offset,

  const nlsp_clv_handle_t *opts, int len, int unknown_tree_id _U_)

{

  uint8_t code;

  uint8_t length;

  int q;

  proto_tree  *clv_tree;

  while ( len > 0 ) {

    code = tvb_get_uint8(tvb, offset);

    offset += 1;

    len -= 1;

    if (len == 0)

      break;

    length = tvb_get_uint8(tvb, offset);

    offset += 1;

    len -= 1;

    if (len == 0)

      break;

    if ( len < length ) {

      proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

        "Short CLV header (%d vs %d)", length, len );

      return;

    }

    q = 0;

    while ((opts[q].dissect != NULL )&&( opts[q].optcode != code )){

      q++;

    }

    if ( opts[q].dissect ) {

      /* adjust by 2 for code/len octets */

      clv_tree = proto_tree_add_subtree_format(tree, tvb, offset - 2,

          length + 2, *opts[q].tree_id, NULL, "%s (%u)",

          opts[q].tree_text, length );

      opts[q].dissect(tvb, pinfo, clv_tree, offset,

          length);

    } else {

      proto_item* ti;

      ti = proto_tree_add_uint_format_value(tree, hf_nlsp_unknown_code, tvb, offset - 2,

          1, code, "%u (%u)", code, length);

      proto_item_set_len(ti, length + 2);

    }

    offset += length;

    len -= length;

  }

}

/*

 * Name: dissect_area_address_clv()

 *

 * Description:

 *  Decode an area address clv.

 *

 * Input:

 *  tvbuff_t * : tvbuffer for packet data

 *  proto_tree * : protocol display tree to fill out.  May be NULL

 *  int : offset into packet data where we are.

 *  int : length of clv we are decoding

 *

 * Output:

 *      void, but we will add to proto tree if !NULL.

 */

static void

dissect_area_address_clv(tvbuff_t *tvb, packet_info* pinfo, proto_tree *tree, unsigned offset,

       unsigned length)

{

  while (length > 0) {

    if (length < 4) {

      proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

          "Short area address entry");

      return;

    }

    proto_tree_add_item(tree, hf_nlsp_area_address_network_number, tvb, offset, 4, ENC_BIG_ENDIAN);

    offset += 4;

    length -= 4;

    if (length < 4) {

      proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

          "Short area address entry");

      return;

    }

    proto_tree_add_item(tree, hf_nlsp_area_address_mask, tvb, offset, 4, ENC_BIG_ENDIAN);

    offset += 4;

    length -= 4;

  }

}

/*

 * Name: dissect_neighbor_clv()

 *

 * Description:

 *  Decode an neighbor clv.

 *

 * Input:

 *  tvbuff_t * : tvbuffer for packet data

 *  proto_tree * : protocol display tree to fill out.  May be NULL

 *  int : offset into packet data where we are.

 *  int : length of clv we are decoding

 *

 * Output:

 *      void, but we will add to proto tree if !NULL.

 */

static void

dissect_neighbor_clv(tvbuff_t *tvb, packet_info* pinfo, proto_tree *tree, unsigned offset,

         unsigned length)

{

  while (length > 0) {

    if (length < 6) {

      proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet,

          tvb, offset, "Short neighbor entry");

      return;

    }

    proto_tree_add_item(tree, hf_nlsp_neighbor, tvb, offset, 6, ENC_NA);

    offset += 6;

    length -= 6;

  }

}

/*

 * Name: dissect_hello_local_mtu_clv()

 *

 * Description:

 *  Decode for a hello packet's local MTU clv.

 *

 * Input:

 *  tvbuff_t * : tvbuffer for packet data

 *  proto_tree * : protocol display tree to fill out.  May be NULL

 *  int : offset into packet data where we are.

 *  int : length of clv we are decoding

 *

 * Output:

 *      void, but we will add to proto tree if !NULL.

 */

static void

dissect_hello_local_mtu_clv(tvbuff_t *tvb, packet_info* pinfo, proto_tree *tree, unsigned offset,

          unsigned length)

{

  if (length < 4) {

    proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

        "Short link info entry");

    return;

  }

  proto_tree_add_item(tree, hf_nlsp_hello_local_mtu_mtu_size, tvb, offset, 4, ENC_BIG_ENDIAN);

}

static const nlsp_clv_handle_t clv_hello_opts[] = {

  {

    0xC0,

    "Area address(es)",

    &ett_nlsp_hello_clv_area_addr,

    dissect_area_address_clv

  },

  {

    6,

    "Neighbors",

    &ett_nlsp_hello_clv_neighbors,

    dissect_neighbor_clv

  },

  {

    0xC5,

    "Local MTU",

    &ett_nlsp_hello_local_mtu,

    dissect_hello_local_mtu_clv

  },

  {

    0,

    "",

    NULL,

    NULL

  }

};

/*

 * Name: nlsp_dissect_nlsp_hello()

 *

 * Description:

 *  This procedure rips apart NLSP hellos.

 *

 * Input:

 *  tvbuff_t * : tvbuffer for packet data

 *  proto_tree * : protocol display tree to add to.  May be NULL.

 *  unsigned offset : our offset into packet data.

 *  int : hello type, a la NLSP_TYPE_* values

 *  int : header length of packet.

 *

 * Output:

 *  void, will modify proto_tree if not NULL.

 */

#define NLSP_HELLO_CTYPE_MASK   0x03

#define NLSP_HELLO_STATE_MASK   0xC0

#define NLSP_HELLO_MULTICAST_MASK 0x10

static const value_string nlsp_hello_state_vals[] = {

  { 0, "Up" },

  { 1, "Initializing" },

  { 2, "Down" },

  { 0, NULL }

};

#define NLSP_HELLO_TYPE_RESERVED  0

#define NLSP_HELLO_TYPE_LEVEL_1   1

#define NLSP_HELLO_TYPE_LEVEL_2   2

#define NLSP_HELLO_TYPE_LEVEL_12  3

static const value_string nlsp_hello_circuit_type_vals[] = {

  { NLSP_HELLO_TYPE_RESERVED, "Reserved 0 (discard PDU)"},

  { NLSP_HELLO_TYPE_LEVEL_1,  "Level 1 only"},

  { NLSP_HELLO_TYPE_LEVEL_2,  "Level 2 only"},

  { NLSP_HELLO_TYPE_LEVEL_12, "Level 1 and 2"},

  { 0,    NULL}

};

#define NLSP_HELLO_PRIORITY_MASK  0x7f

static void

nlsp_dissect_nlsp_hello(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree,

      unsigned offset, int hello_type, int header_length)

{

  uint16_t    packet_length;

  int     len;

  if (hello_type == NLSP_TYPE_WAN_HELLO) {

    proto_tree_add_item(tree, hf_nlsp_hello_state, tvb,

      offset, 1, ENC_BIG_ENDIAN);

  } else {

    proto_tree_add_item(tree, hf_nlsp_hello_multicast, tvb,

      offset, 1, ENC_BIG_ENDIAN);

  }

  proto_tree_add_item(tree, hf_nlsp_hello_circuit_type, tvb,

    offset, 1, ENC_BIG_ENDIAN);

  offset += 1;

  proto_tree_add_item(tree, hf_nlsp_hello_sending_router_system_id, tvb, offset, 6, ENC_NA);

  col_append_fstr(pinfo->cinfo, COL_INFO, ", System ID: %s",

        tvb_ether_to_str(pinfo->pool, tvb, offset));

  offset += 6;

  proto_tree_add_item(tree, hf_nlsp_hello_holding_timer, tvb, offset, 2, ENC_BIG_ENDIAN);

  offset += 2;

  packet_length = tvb_get_ntohs(tvb, offset);

  proto_tree_add_uint(tree, hf_nlsp_packet_length, tvb, offset, 2, packet_length);

  offset += 2;

  proto_tree_add_item(tree, hf_nlsp_hello_priority, tvb, offset, 1, ENC_BIG_ENDIAN);

  offset += 1;

  if (hello_type == NLSP_TYPE_WAN_HELLO) {

    proto_tree_add_item(tree, hf_nlsp_hello_local_wan_circuit_id, tvb, offset, 1, ENC_BIG_ENDIAN);

    offset += 1;

  } else {

    proto_tree_add_item(tree, hf_nlsp_hello_designated_router_system_id, tvb, offset, 6, ENC_NA);

    proto_tree_add_item(tree, hf_nlsp_hello_designated_router_pseudonode_id, tvb, offset+6, 1, ENC_BIG_ENDIAN);

    offset += 7;

  }

  len = packet_length - header_length;

  if (len < 0) {

    proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_long_packet, tvb, offset,

      "packet header length %d went beyond packet",

      header_length);

    return;

  }

  /*

   * Now, we need to decode our CLVs.  We need to pass in

   * our list of valid ones!

   */

  nlsp_dissect_clvs(tvb, pinfo, tree, offset,

      clv_hello_opts, len, ett_nlsp_hello_clv_unknown);

}

/*

 * Name: dissect_lsp_mgt_info_clv()

 *

 * Description:

 *  Decode for a lsp packet's management information clv.

 *

 * Input:

 *  tvbuff_t * : tvbuffer for packet data

 *  proto_tree * : protocol display tree to fill out.  May be NULL

 *  int : offset into packet data where we are.

 *  int : length of clv we are decoding

 *

 * Output:

 *      void, but we will add to proto tree if !NULL.

 */

static void

dissect_lsp_mgt_info_clv(tvbuff_t *tvb, packet_info* pinfo, proto_tree *tree, unsigned offset,

       unsigned length)

{

  uint8_t name_length;

  if (length < 4) {

    proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

        "Short management info entry");

    return;

  }

  proto_tree_add_item(tree, hf_nlsp_mgt_info_network_number, tvb, offset, 4, ENC_BIG_ENDIAN);

  offset += 4;

  length -= 4;

  if (length < 6) {

    proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

        "Short management info entry");

    return;

  }

  proto_tree_add_item(tree, hf_nlsp_mgt_info_node_number, tvb, offset, 6, ENC_NA);

  offset += 6;

  length -= 6;

  if (length < 1) {

    proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

        "Short management info entry");

    return;

  }

  proto_tree_add_item(tree, hf_nlsp_mgt_info_ipx_version_number, tvb, offset, 1, ENC_BIG_ENDIAN);

  offset += 1;

  length -= 1;

  if (length < 1) {

    proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

        "Short management info entry");

    return;

  }

  proto_tree_add_item_ret_uint8(tree, hf_nlsp_mgt_info_name_length, tvb, offset, 1, ENC_BIG_ENDIAN, &name_length);

  offset += 1;

  length -= 1;

  if (name_length != 0) {

    if (length < name_length) {

      proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

          "Short management info entry");

      return;

    }

    proto_tree_add_item(tree, hf_nlsp_mgt_info_name, tvb, offset, name_length, ENC_ASCII);

  }

}

/*

 * Name: dissect_lsp_link_info_clv()

 *

 * Description:

 *  Decode for a lsp packet's link information clv.

 *

 * Input:

 *  tvbuff_t * : tvbuffer for packet data

 *  proto_tree * : protocol display tree to fill out.  May be NULL

 *  int : offset into packet data where we are.

 *  int : length of clv we are decoding

 *

 * Output:

 *      void, but we will add to proto tree if !NULL.

 */

static const value_string media_type_vals[] = {

  { 0x0000, "Generic LAN" },

  { 0x8000, "Generic WAN" },

  { 0x0001, "Localtalk" },

  { 0x0002, "Ethernet II" },

  { 0x0003, "IEEE 802.3 with IEEE 802.2 without SNAP" },

  { 0x0005, "IEEE 802.3 with IPX header and no 802.2 header" },

  { 0x000A, "IEEE 802.3 with IEEE 802.2 and SNAP" },

  { 0x0004, "IEEE 802.5 with IEEE 802.2 without SNAP" },

  { 0x000B, "IEEE 802.5 with IEEE 802.2 and SNAP" },

  { 0x0006, "IEEE 802.4" },

  { 0x0007, "IBM PC Network II" },

  { 0x0008, "Gateway G/Net" },

  { 0x0009, "Proteon ProNET" },

  { 0x000C, "Racore LANPAC" },

  { 0x800D, "ISDN" },

  { 0x000E, "ARCnet" },

  { 0x000F, "IBM PC Network II with 802.2 without SNAP" },

  { 0x0010, "IBM PC Network II with 802.2 and SNAP" },

  { 0x0011, "Corvus OmniNet at 4 Mbps" },

  { 0x0012, "Harris Adacom" },

  { 0x0013, "IP tunnel" },

  { 0x8013, "IP Relay" },

  { 0x0014, "FDDI with 802.2 without SNAP" },

  { 0x0015, "Commtex IVDLAN" },

  { 0x0016, "Dataco OSI" },

  { 0x0017, "FDDI with 802.2 and SNAP" },

  { 0x0018, "IBM SDLC tunnel" },

  { 0x0019, "PC Office frame" },

  { 0x001A, "Hypercommunications WAIDNET" },

  { 0x801C, "PPP" },

  { 0x801D, "Proxim RangeLAN" },

  { 0x801E, "X.25" },

  { 0x801F, "Frame Relay" },

  { 0x0020, "Integrated Workstations BUS-NET" },

  { 0x8021, "Novell SNA Links" },

  { 0,      NULL }

};

static void

dissect_lsp_link_info_clv(tvbuff_t *tvb, packet_info* pinfo, proto_tree *tree, unsigned offset,

        unsigned length)

{

  uint8_t flags_cost;

  if (length < 1) {

    proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

        "Short link info entry");

    return;

  }

  if (tree) {

    flags_cost = tvb_get_uint8(tvb, offset);

    proto_tree_add_item(tree, hf_nlsp_lsp_link_info_clv_flags_cost_present, tvb, offset, 1, ENC_BIG_ENDIAN);

    if (!(flags_cost & 0x80)) {

      /*

       * 0x80 clear => cost present.

       */

      proto_tree_add_item(tree, hf_nlsp_lsp_link_info_clv_flags_cost_metric, tvb, offset, 1, ENC_BIG_ENDIAN);

      proto_tree_add_item(tree, hf_nlsp_lsp_link_info_clv_flags_cost, tvb, offset, 1, ENC_BIG_ENDIAN);

    }

  }

  offset += 1;

  length -= 1;

  if (length < 3) {

    proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

        "Short link info entry");

    return;

  }

  offset += 3;  /* Reserved */

  length -= 3;

  if (length < 7) {

    proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

        "Short link info entry");

    return;

  }

  proto_tree_add_item(tree, hf_nlsp_link_info_router_system_id, tvb, offset, 6, ENC_NA);

  proto_tree_add_item(tree, hf_nlsp_link_info_router_pseudonode_id, tvb, offset+6, 1, ENC_BIG_ENDIAN);

  offset += 7;

  length -= 7;

  if (length < 4) {

    proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

        "Short link info entry");

    return;

  }

  proto_tree_add_item(tree, hf_nlsp_link_info_mtu_size, tvb, offset, 4, ENC_BIG_ENDIAN);

  offset += 4;

  length -= 4;

  if (length < 4) {

    proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

        "Short link info entry");

    return;

  }

  proto_tree_add_item(tree, hf_nlsp_link_info_delay, tvb, offset, 4, ENC_BIG_ENDIAN);

  offset += 4;

  length -= 4;

  if (length < 4) {

    proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

        "Short link info entry");

    return;

  }

  proto_tree_add_item(tree, hf_nlsp_link_info_throughput, tvb, offset, 4, ENC_BIG_ENDIAN);

  offset += 4;

  length -= 4;

  if (length < 2) {

    proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

        "Short link info entry");

    return;

  }

  proto_tree_add_item(tree, hf_nlsp_link_info_media_type, tvb, offset, 2, ENC_BIG_ENDIAN);

}

/*

 * Name: dissect_lsp_svcs_info_clv()

 *

 * Description:

 *  Decode for a lsp packet's services information clv.

 *

 * Input:

 *  tvbuff_t * : tvbuffer for packet data

 *  proto_tree * : protocol display tree to fill out.  May be NULL

 *  int : offset into packet data where we are.

 *  int : length of clv we are decoding

 *

 * Output:

 *      void, but we will add to proto tree if !NULL.

 */

static void

dissect_lsp_svcs_info_clv(tvbuff_t *tvb, packet_info* pinfo, proto_tree *tree, unsigned offset,

        unsigned length)

{

  if (length < 1) {

    proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

        "Short services info entry");

    return;

  }

  proto_tree_add_item(tree, hf_nlsp_svcs_info_hops_to_reach_the_service, tvb, offset, 1, ENC_BIG_ENDIAN);

  offset += 1;

  length -= 1;

  if (length < 4) {

    proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

        "Short services info entry");

    return;

  }

  proto_tree_add_item(tree, hf_nlsp_svcs_info_network_number, tvb, offset, 4, ENC_BIG_ENDIAN);

  offset += 4;

  length -= 4;

  if (length < 6) {

    proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

        "Short services info entry");

    return;

  }

  proto_tree_add_item(tree, hf_nlsp_svcs_info_node_number, tvb, offset, 6, ENC_NA);

  offset += 6;

  length -= 6;

  if (length < 2) {

    proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

        "Short services info entry");

    return;

  }

  proto_tree_add_item(tree, hf_nlsp_svcs_info_socket, tvb, offset, 2, ENC_BIG_ENDIAN);

  offset += 2;

  length -= 2;

  if (length < 2) {

    proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

        "Short services info entry");

    return;

  }

  proto_tree_add_item(tree, hf_nlsp_svcs_info_type, tvb, offset, 2, ENC_BIG_ENDIAN);

  offset += 2;

  length -= 2;

  if (length > 0) {

    proto_tree_add_item(tree, hf_nlsp_svcs_info_service_name, tvb, offset, length, ENC_ASCII);

  }

}

/*

 * Name: dissect_lsp_ext_routes_clv()

 *

 * Description:

 *  Decode for a lsp packet's external routes clv.

 *

 * Input:

 *  tvbuff_t * : tvbuffer for packet data

 *  proto_tree * : protocol display tree to fill out.  May be NULL

 *  int : offset into packet data where we are.

 *  int : length of clv we are decoding

 *

 * Output:

 *      void, but we will add to proto tree if !NULL.

 */

static void

dissect_lsp_ext_routes_clv(tvbuff_t *tvb, packet_info* pinfo, proto_tree *tree, unsigned offset,

         unsigned length)

{

  while (length > 0) {

    proto_tree_add_item(tree, hf_nlsp_ext_routes_hops, tvb, offset, 1, ENC_BIG_ENDIAN);

    offset += 1;

    length -= 1;

    if (length < 4) {

      proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

          "Short external routes entry");

      return;

    }

    proto_tree_add_item(tree, hf_nlsp_ext_routes_network_number, tvb, offset, 4, ENC_BIG_ENDIAN);

    offset += 4;

    length -= 4;

    if (length < 2) {

      proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

          "Short external routes entry");

      return;

    }

    proto_tree_add_item(tree, hf_nlsp_ext_routes_rip_delay, tvb, offset, 2, ENC_BIG_ENDIAN);

    offset += 2;

    length -= 2;

  }

}

static const nlsp_clv_handle_t clv_l1_lsp_opts[] = {

  {

    0xC0,

    "Area address(es)",

    &ett_nlsp_lsp_clv_area_addr,

    dissect_area_address_clv

  },

  {

    0xC1,

    "Management information",

    &ett_nlsp_lsp_clv_mgt_info,

    dissect_lsp_mgt_info_clv

  },

  {

    0xC2,

    "Link information",

    &ett_nlsp_lsp_clv_link_info,

    dissect_lsp_link_info_clv

  },

  {

    0xC3,

    "Services information",

    &ett_nlsp_lsp_clv_svcs_info,

    dissect_lsp_svcs_info_clv

  },

  {

    0xC4,

    "External routes",

    &ett_nlsp_lsp_clv_ext_routes,

    dissect_lsp_ext_routes_clv

  },

  {

    0,

    "",

    NULL,

    NULL

  }

};

/*

 * Name: nlsp_dissect_nlsp_lsp()

 *

 * Description:

 *  Print out the LSP part of the main header and then call the CLV

 *  de-mangler with the right list of valid CLVs.

 *

 * Input:

 *  tvbuff_t * : tvbuffer for packet data

 *  proto_tree * : protocol display tree to add to.  May be NULL.

 *  unsigned offset : our offset into packet data.

 *  int : header length of packet.

 *

 * Output:

 *      void, but we will add to proto tree if !NULL.

 */

/* P | ATT | OVERFLOW | ROUTER TYPE FIELD description */

#define NLSP_LSP_PARTITION_MASK     0x80

#define NLSP_LSP_PARTITION_SHIFT    7

#define NLSP_LSP_PARTITION(info)    (((info) & NLSP_LSP_PARTITION_MASK) >> NLSP_LSP_PARTITION_SHIFT)

#define NLSP_LSP_ATT_MASK     0x78

#define NLSP_LSP_ATT_SHIFT    3

#define NLSP_LSP_ATT(info)    (((info) & NLSP_LSP_ATT_MASK) >> NLSP_LSP_ATT_SHIFT)

#define NLSP_LSP_OVERFLOW_MASK     0x04

#define NLSP_LSP_OVERFLOW_SHIFT    2

#define NLSP_LSP_OVERFLOW(info)    (((info) & NLSP_LSP_OVERFLOW_MASK) >> NLSP_LSP_OVERFLOW_SHIFT)

#define NLSP_LSP_ROUTER_TYPE_MASK     0x03

#define NLSP_LSP_ROUTER_TYPE(info)    ((info) & NLSP_LSP_ROUTER_TYPE_MASK)

static void

nlsp_dissect_nlsp_lsp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree,

          unsigned offset, int header_length)

{

  uint16_t    packet_length;

  uint16_t    remaining_lifetime;

  uint32_t    sequence_number;

  int   len;

  packet_length = tvb_get_ntohs(tvb, offset);

  proto_tree_add_uint(tree, hf_nlsp_packet_length, tvb,

      offset, 2, packet_length);

  offset += 2;

  remaining_lifetime = tvb_get_ntohs(tvb, offset);

  proto_tree_add_uint(tree, hf_nlsp_remaining_lifetime, tvb, offset, 2, remaining_lifetime);

  offset += 2;

  col_append_fstr(pinfo->cinfo, COL_INFO, ", LSP ID: %s",

        tvb_ether_to_str(pinfo->pool, tvb, offset));

  proto_tree_add_item(tree, hf_nlsp_lsp_id_system_id, tvb, offset, 6, ENC_NA);

  offset += 6;

  /* XXX - append the pseudonode ID */

  proto_tree_add_item(tree, hf_nlsp_lsp_id_pseudonode_id, tvb, offset, 1, ENC_BIG_ENDIAN);

  offset += 1;

  proto_tree_add_item(tree, hf_nlsp_lsp_id_lsp_number, tvb, offset, 1, ENC_BIG_ENDIAN);

  offset += 1;

  sequence_number = tvb_get_ntohl(tvb, offset);

  col_append_fstr(pinfo->cinfo, COL_INFO,

        ", Sequence: 0x%08x, Lifetime: %us",

        sequence_number, remaining_lifetime);

  proto_tree_add_uint(tree, hf_nlsp_lsp_sequence_number, tvb,

      offset, 4, sequence_number);

  offset += 4;

  /* XXX -> we could validate the cksum here! */

  proto_tree_add_checksum(tree, tvb, offset, hf_nlsp_lsp_checksum, -1, NULL, pinfo, 0, ENC_BIG_ENDIAN, PROTO_CHECKSUM_NO_FLAGS);

  offset += 2;

  if (tree) {

    proto_tree_add_item(tree, hf_nlsp_lsp_p, tvb,

        offset, 1, ENC_BIG_ENDIAN);

    proto_tree_add_item(tree, hf_nlsp_lsp_attached_flag, tvb,

        offset, 1, ENC_BIG_ENDIAN);

    proto_tree_add_item(tree, hf_nlsp_lsp_lspdbol, tvb,

        offset, 1, ENC_BIG_ENDIAN);

    proto_tree_add_item(tree, hf_nlsp_lsp_router_type, tvb,

        offset, 1, ENC_BIG_ENDIAN);

  }

  offset += 1;

  len = packet_length - header_length;

  if (len < 0) {

    proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_long_packet, tvb, offset,

      "packet header length %d went beyond packet",

       header_length);

    return;

  }

  /*

   * Now, we need to decode our CLVs.  We need to pass in

   * our list of valid ones!

   */

  nlsp_dissect_clvs(tvb, pinfo, tree, offset,

    clv_l1_lsp_opts, len, ett_nlsp_lsp_clv_unknown);

}

/*

 * Name: dissect_snp_lsp_entries()

 *

 * Description:

 *  All the snp packets use a common payload format.  We have up

 *  to n entries (based on length), which are made of:

 *    2 : remaining life time

 *    8 : lsp id

 *    4 : sequence number

 *    2 : checksum

 *

 * Input:

 *  tvbuff_t * : tvbuffer for packet data

 *  proto_tree * : protocol display tree to fill out.  May be NULL

 *  int : offset into packet data where we are.

 *  int : length of payload to decode.

 *

 * Output:

 *      void, but we will add to proto tree if !NULL.

 */

static void

dissect_csnp_lsp_entries(tvbuff_t *tvb, packet_info* pinfo, proto_tree *tree, unsigned offset,

       unsigned length)

{

  proto_tree *subtree;

  while (length > 0) {

    if (length < 16) {

      proto_tree_add_expert_format_remaining(tree, pinfo, &ei_nlsp_short_packet, tvb, offset,

          "Short CSNP header entry");

      return;

    }

    subtree = proto_tree_add_subtree_format(tree, tvb, offset, 16,

        ett_nlsp_csnp_lsp_entry, NULL, "LSP-ID: %s, Sequence: 0x%08x, Lifetime: %5us, Checksum: 0x%04x",

        tvb_ether_to_str(pinfo->pool, tvb, offset+2), /* XXX - rest of system ID */

        tvb_get_ntohl(tvb, offset+10),

        tvb_get_ntohs(tvb, offset),

        tvb_get_ntohs(tvb, offset+14));

    proto_tree_add_item(subtree, hf_nlsp_csnp_lsp_id_source_id, tvb, offset+2, 6, ENC_NA);

    proto_tree_add_item(subtree, hf_nlsp_csnp_lsp_id_pseudonode_id, tvb, offset+8, 1, ENC_BIG_ENDIAN);

    proto_tree_add_item(subtree, hf_nlsp_csnp_lsp_id_lsp_number, tvb, offset+9, 1, ENC_BIG_ENDIAN);

    proto_tree_add_item(subtree, hf_nlsp_csnp_lsp_sequence_number, tvb, offset+10, 4, ENC_BIG_ENDIAN);

    proto_tree_add_item(subtree, hf_nlsp_csnp_remaining_lifetime, tvb, offset, 2, ENC_BIG_ENDIAN);