/* packet-foundry.c

 * Routines for the disassembly of Foundry LLC messages (currently

 * Foundry Discovery Protocol - FDP only)

 *

 * Copyright 2012 Joerg Mayer (see AUTHORS file)

 *

 * 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/strutil.h>

#include "packet-llc.h"

#include <epan/oui.h>

void proto_register_fdp(void);

void proto_reg_handoff_fdp(void);

static dissector_handle_t fdp_handle;

static int hf_llc_foundry_pid;

static int proto_fdp;

/* FDP header */

static int hf_fdp_version;

static int hf_fdp_holdtime;

static int hf_fdp_checksum;

/* TLV header */

static int hf_fdp_tlv_type;

static int hf_fdp_tlv_length;

/* Unknown element */

static int hf_fdp_unknown;

static int hf_fdp_unknown_data;

/* Port Tag element */

static int hf_fdp_tag;

static int hf_fdp_tag_native;

static int hf_fdp_tag_type;

static int hf_fdp_tag_unknown;

/* VLAN Bitmap */

static int hf_fdp_vlanmap;

static int hf_fdp_vlanmap_vlan;

/* String element */

static int hf_fdp_string;

static int hf_fdp_string_data;

static int hf_fdp_string_text;

/* Net? element */

static int hf_fdp_net;

static int hf_fdp_net_unknown;

static int hf_fdp_net_ip;

static int hf_fdp_net_iplength;

static int ett_fdp;

static int ett_fdp_tlv_header;

static int ett_fdp_unknown;

static int ett_fdp_string;

static int ett_fdp_net;

static int ett_fdp_tag;

static int ett_fdp_vlanmap;

static expert_field ei_fdp_tlv_length;

#define PROTO_SHORT_NAME "FDP"

#define PROTO_LONG_NAME "Foundry Discovery Protocol"

static const value_string foundry_pid_vals[] = {

  { 0x2000, "FDP" },

  { 0,    NULL }

};

typedef enum {

  FDP_TYPE_NAME = 1,

  FDP_TYPE_NET = 2,

  FDP_TYPE_PORT = 3,

  FDP_TYPE_CAPABILITIES = 4,

  FDP_TYPE_VERSION = 5,

  FDP_TYPE_MODEL = 6,

  FDP_TYPE_VLANMAP = 0x0101,

  FDP_TYPE_TAG = 0x0102

} fdp_type_t;

static const value_string fdp_type_vals[] = {

  { FDP_TYPE_NAME,    "DeviceID"},

  { FDP_TYPE_NET,     "Net?"},

  { FDP_TYPE_PORT,    "Interface"},

  { FDP_TYPE_CAPABILITIES,  "Capabilities"},

  { FDP_TYPE_VERSION,   "Version"},

  { FDP_TYPE_MODEL,   "Platform"},

  { FDP_TYPE_VLANMAP,   "VLAN-Bitmap"},

  { FDP_TYPE_TAG,     "Tagging-Info"},

  { 0,    NULL }

};

static int

dissect_tlv_header(tvbuff_t *tvb, packet_info *pinfo _U_, int offset, int length _U_, proto_tree *tree)

{

  proto_tree  *tlv_tree;

  uint16_t    tlv_type;

  uint16_t    tlv_length;

  tlv_type = tvb_get_ntohs(tvb, offset);

  tlv_length = tvb_get_ntohs(tvb, offset + 2);

  tlv_tree = proto_tree_add_subtree_format(tree, tvb, offset, 4,

    ett_fdp_tlv_header, NULL, "Length %d, type %d = %s",

    tlv_length, tlv_type,

    val_to_str(pinfo->pool, tlv_type, fdp_type_vals, "Unknown (%d)"));

  proto_tree_add_uint(tlv_tree, hf_fdp_tlv_type, tvb, offset, 2, tlv_type);

  offset += 2;

  proto_tree_add_uint(tlv_tree, hf_fdp_tlv_length, tvb, offset, 2, tlv_length);

  offset += 2;

  return offset;

}

static int

dissect_string_tlv(tvbuff_t *tvb, packet_info *pinfo, int offset, int length, proto_tree *tree, const char* type_string)

{

  proto_item  *string_item;

  proto_tree  *string_tree;

  const char  *string_value;

  string_item = proto_tree_add_protocol_format(tree, hf_fdp_string,

    tvb, offset, length, "%s", type_string);

  string_tree = proto_item_add_subtree(string_item, ett_fdp_string);

  dissect_tlv_header(tvb, pinfo, offset, 4, string_tree);

  offset += 4;

  length -= 4;

  proto_tree_add_item(string_tree, hf_fdp_string_data, tvb, offset, length, ENC_NA);

  proto_tree_add_item_ret_string(string_tree, hf_fdp_string_text, tvb, offset, length, ENC_ASCII|ENC_NA, pinfo->pool, (const uint8_t**)&string_value);

  proto_item_append_text(string_item, ": \"%s\"",

    format_text(pinfo->pool, string_value, strlen(string_value)));

  return offset;

}

static void

dissect_net_tlv(tvbuff_t *tvb, packet_info *pinfo, int offset, int length, proto_tree *tree)

{

  proto_item  *net_item;

  proto_tree  *net_tree;

  net_item = proto_tree_add_protocol_format(tree, hf_fdp_net,

    tvb, offset, length, "Net?");

  net_tree = proto_item_add_subtree(net_item, ett_fdp_net);

  dissect_tlv_header(tvb, pinfo, offset, 4, net_tree);

  offset += 4;

  length -= 4;

  proto_tree_add_item(net_tree, hf_fdp_net_unknown, tvb, offset, 7, ENC_NA);

  offset += 7;

  length -= 7;

  /* Length of IP address block in bytes */

  proto_tree_add_item(net_tree, hf_fdp_net_iplength, tvb, offset, 2, ENC_BIG_ENDIAN);

  offset += 2;

  length -= 2;

  while (length >= 4) {

    proto_tree_add_item(net_tree, hf_fdp_net_ip, tvb, offset, 4, ENC_BIG_ENDIAN);

    offset += 4;

    length -= 4;

  }

}

static void

dissect_vlanmap_tlv(tvbuff_t *tvb, packet_info *pinfo, int offset, int length, proto_tree *tree)

{

  proto_item  *vlanmap_item;

  proto_tree  *vlanmap_tree;

  unsigned    vlan, voffset;

  unsigned    bitoffset, byteoffset;

  vlanmap_item = proto_tree_add_protocol_format(tree, hf_fdp_vlanmap,

    tvb, offset, length, "VLAN-Map");

  vlanmap_tree = proto_item_add_subtree(vlanmap_item, ett_fdp_vlanmap);

  dissect_tlv_header(tvb, pinfo, offset, 4, vlanmap_tree);

  offset += 4;

  length -= 4;

  voffset = 1;

  for (vlan = 1; vlan <= (unsigned)length*8; vlan++) {

    byteoffset = (vlan - voffset) / 8;

    bitoffset = (vlan - voffset) % 8;

    if (tvb_get_uint8(tvb, offset + byteoffset) & (1 << bitoffset)) {

      proto_tree_add_uint(vlanmap_tree, hf_fdp_vlanmap_vlan, tvb,

        offset + byteoffset, 1, vlan);

    }

  }

}

static void

dissect_tag_tlv(tvbuff_t *tvb, packet_info *pinfo, int offset, int length, proto_tree *tree)

{

  proto_item  *tag_item;

  proto_tree  *tag_tree;

  tag_item = proto_tree_add_protocol_format(tree, hf_fdp_tag,

    tvb, offset, length, "Port tag");

  tag_tree = proto_item_add_subtree(tag_item, ett_fdp_tag);

  dissect_tlv_header(tvb, pinfo, offset, 4, tag_tree);

  offset += 4;

  length -= 4;

  proto_tree_add_item(tag_tree, hf_fdp_tag_native, tvb, offset, 2, ENC_BIG_ENDIAN);

  offset += 2;

  length -= 2;

  proto_tree_add_item(tag_tree, hf_fdp_tag_type, tvb, offset, 2, ENC_BIG_ENDIAN);

  offset += 2;

  length -= 2;

  proto_tree_add_item(tag_tree, hf_fdp_tag_unknown, tvb, offset, length, ENC_NA);

}

static void

dissect_unknown_tlv(tvbuff_t *tvb, packet_info *pinfo, int offset, int length, proto_tree *tree)

{

  proto_item  *unknown_item;

  proto_tree  *unknown_tree;

  uint16_t    tlv_type;

  tlv_type = tvb_get_ntohs(tvb, offset);

  unknown_item = proto_tree_add_protocol_format(tree, hf_fdp_unknown,

    tvb, offset, length, "Unknown element [%u]", tlv_type);

  unknown_tree = proto_item_add_subtree(unknown_item, ett_fdp_unknown);

  dissect_tlv_header(tvb, pinfo, offset, 4, unknown_tree);

  offset += 4;

  length -= 4;

  proto_tree_add_item(unknown_tree, hf_fdp_unknown_data, tvb, offset, length, ENC_NA);

}

static int

dissect_fdp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)

{

  proto_item *ti;

  proto_tree *fdp_tree = NULL;

  int offset = 0;

  uint16_t tlv_type;

  uint16_t tlv_length;

  int data_length;

  const char *type_string;

  col_set_str(pinfo->cinfo, COL_PROTOCOL, PROTO_SHORT_NAME);

  col_set_str(pinfo->cinfo, COL_INFO, PROTO_SHORT_NAME ":");

  if (tree) {

    data_length = tvb_reported_length_remaining(tvb, offset);

    ti = proto_tree_add_item(tree, proto_fdp, tvb, offset, -1, ENC_NA);

    fdp_tree = proto_item_add_subtree(ti, ett_fdp);

    proto_tree_add_item(fdp_tree, hf_fdp_version, tvb, offset, 1, ENC_BIG_ENDIAN);

    offset += 1;

    proto_tree_add_item(fdp_tree, hf_fdp_holdtime, tvb, offset, 1, ENC_BIG_ENDIAN);

    offset += 1;

    proto_tree_add_checksum(fdp_tree, tvb, offset, hf_fdp_checksum, -1, NULL, pinfo, 0, ENC_BIG_ENDIAN, PROTO_CHECKSUM_NO_FLAGS);

    offset += 2;

    /* Decode the individual TLVs */

    while (offset < data_length) {

      if (data_length - offset < 4) {

        proto_tree_add_expert_format(fdp_tree, pinfo, &ei_fdp_tlv_length, tvb, offset, 4,

          "Too few bytes left for TLV: %u (< 4)", data_length - offset);

        break;

      }

      tlv_type = tvb_get_ntohs(tvb, offset);

      tlv_length = tvb_get_ntohs(tvb, offset + 2);

      if ((tlv_length < 4) || (tlv_length > (data_length - offset))) {

        proto_tree_add_expert_format(fdp_tree, pinfo, &ei_fdp_tlv_length, tvb, offset, 0,

          "TLV with invalid length: %u", tlv_length);

        break;

      }

      type_string = val_to_str(pinfo->pool, tlv_type, fdp_type_vals, "[%u]");

      col_append_fstr(pinfo->cinfo, COL_INFO, " %s", type_string);

      switch (tlv_type) {

      case FDP_TYPE_NAME:

      case FDP_TYPE_PORT:

      case FDP_TYPE_CAPABILITIES:

      case FDP_TYPE_VERSION:

      case FDP_TYPE_MODEL:

        dissect_string_tlv(tvb, pinfo, offset, tlv_length, fdp_tree, type_string);

        break;

      case FDP_TYPE_NET:

        dissect_net_tlv(tvb, pinfo, offset, tlv_length, fdp_tree);

        break;

      case FDP_TYPE_TAG:

        dissect_tag_tlv(tvb, pinfo, offset, tlv_length, fdp_tree);

        break;

      case FDP_TYPE_VLANMAP:

        dissect_vlanmap_tlv(tvb, pinfo, offset, tlv_length, fdp_tree);

        break;

      default:

        dissect_unknown_tlv(tvb, pinfo, offset, tlv_length, fdp_tree);

        break;

      }

      offset += tlv_length;

    }

  }

  return tvb_captured_length(tvb);

}

void

proto_register_fdp(void)

{

  static hf_register_info hf[] = {

  /* FDP header */

    { &hf_fdp_version,

    { "Version?", "fdp.version", FT_UINT8, BASE_DEC, NULL,

      0x0, NULL, HFILL }},

    { &hf_fdp_holdtime,

    { "Holdtime", "fdp.holdtime", FT_UINT8, BASE_DEC, NULL,

      0x0, NULL, HFILL }},

    { &hf_fdp_checksum,

    { "Checksum?",  "fdp.checksum", FT_UINT16, BASE_HEX, NULL,

      0x0, NULL, HFILL }},

  /* TLV header */

    { &hf_fdp_tlv_type,

    { "TLV type", "fdp.tlv.type", FT_UINT16, BASE_DEC, VALS(fdp_type_vals),

      0x0, NULL, HFILL }},

    { &hf_fdp_tlv_length,

    { "TLV length", "fdp.tlv.length", FT_UINT16, BASE_DEC, NULL,

      0x0, NULL, HFILL }},

  /* Unknown element */

    { &hf_fdp_unknown,

    { "Unknown",  "fdp.unknown", FT_PROTOCOL, BASE_NONE, NULL,

      0x0, NULL, HFILL }},

    { &hf_fdp_unknown_data,

    { "Unknown",  "fdp.unknown.data", FT_BYTES, BASE_NONE, NULL,

      0x0, NULL, HFILL }},

  /* String element */

    { &hf_fdp_string,

    { "DeviceID", "fdp.deviceid", FT_PROTOCOL, BASE_NONE, NULL,

      0x0, NULL, HFILL }},

    { &hf_fdp_string_data,

    { "Data", "fdp.string.data", FT_BYTES, BASE_NONE, NULL,

      0x0, NULL, HFILL }},

    { &hf_fdp_string_text,

    { "Text", "fdp.string.text", FT_STRING, BASE_NONE, NULL,

      0x0, NULL, HFILL }},

  /* Net? element */

    { &hf_fdp_net,

    { "Net?", "fdp.net", FT_PROTOCOL, BASE_NONE, NULL,

      0x0, NULL, HFILL }},

    { &hf_fdp_net_unknown,

    { "Net Unknown?", "fdp.net.unknown", FT_BYTES, BASE_NONE, NULL,

      0x0, NULL, HFILL }},

    { &hf_fdp_net_iplength,

    { "Net IP Bytes?",  "fdp.net.iplength", FT_UINT16, BASE_DEC, NULL,

      0x0, "Number of bytes carrying IP addresses", HFILL }},

    { &hf_fdp_net_ip,

    { "Net IP Address?",  "fdp.net.ip", FT_IPv4, BASE_NONE, NULL,

      0x0, NULL, HFILL }},

  /* VLAN Bitmap */

    { &hf_fdp_vlanmap,

    { "VLAN Map", "fdp.vlanmap", FT_PROTOCOL, BASE_NONE, NULL,

      0x0, NULL, HFILL }},

    { &hf_fdp_vlanmap_vlan,

    { "VLAN",   "fdp.vlanmap.vlan", FT_UINT16, BASE_DEC, NULL,

      0x0, NULL, HFILL }},

  /* Port Tag element */

    { &hf_fdp_tag,

    { "Tag",  "fdp.tag", FT_PROTOCOL, BASE_NONE, NULL,

      0x0, NULL, HFILL }},

    { &hf_fdp_tag_native,

    { "Native", "fdp.tag.native", FT_UINT16, BASE_DEC, NULL,

      0x0, NULL, HFILL }},

    { &hf_fdp_tag_type,

    { "Type", "fdp.tag.type", FT_UINT16, BASE_HEX, NULL,

      0x0, NULL, HFILL }},

    { &hf_fdp_tag_unknown,

    { "Unknown",  "fdp.tag.unknown", FT_BYTES, BASE_NONE, NULL,

      0x0, NULL, HFILL }},

  };

  static hf_register_info oui_hf[] = {

    { &hf_llc_foundry_pid,

    { "PID",  "llc.foundry_pid",  FT_UINT16, BASE_HEX,

      VALS(foundry_pid_vals), 0x0, NULL, HFILL }

    }

  };

  static int *ett[] = {

    &ett_fdp,

    &ett_fdp_tlv_header,

    &ett_fdp_unknown,

    &ett_fdp_string,

    &ett_fdp_net,

    &ett_fdp_tag,

    &ett_fdp_vlanmap,

  };

  static ei_register_info ei[] = {

    { &ei_fdp_tlv_length, { "fdp.tlv.length.invalid", PI_MALFORMED, PI_ERROR, "Invalid length", EXPFILL }},

  };

  expert_module_t* expert_fdp;

  proto_fdp = proto_register_protocol(PROTO_LONG_NAME, PROTO_SHORT_NAME, "fdp");

  proto_register_field_array(proto_fdp, hf, array_length(hf));

  proto_register_subtree_array(ett, array_length(ett));

  expert_fdp = expert_register_protocol(proto_fdp);

  expert_register_field_array(expert_fdp, ei, array_length(ei));

  llc_add_oui(OUI_FOUNDRY, "llc.foundry_pid", "LLC Foundry OUI PID", oui_hf, proto_fdp);

  fdp_handle = register_dissector("fdp", dissect_fdp, proto_fdp);

}

void

proto_reg_handoff_fdp(void)

{

  dissector_add_uint("llc.foundry_pid", 0x2000, fdp_handle);

}

/*

 * Editor modelines  -  https://www.wireshark.org/tools/modelines.html

 *

 * Local variables:

 * c-basic-offset: 8

 * tab-width: 8

 * indent-tabs-mode: t

 * End:

 *

 * vi: set shiftwidth=8 tabstop=8 noexpandtab:

 * :indentSize=8:tabSize=8:noTabs=false:

 */