/src/wireshark/epan/dissectors/packet-ansi_801.c

Source (jump to first uncovered line)
/* packet-ansi_801.c
 * Routines for ANSI IS-801 (Location Services (PLD)) dissection
 *
 *   Location Services (Position Determination Service)
 *      3GPP2 C.S0022-0 v1.0  IS-801
 *
 *   Location Services (Position Determination Service)
 *      3GPP2 C.S0022-0-1 v1.0  IS-801 Addendum
 *
 * Copyright 2004, Michael Lum <mlum [AT] telostech.com>
 * In association with Telos Technology Inc.
 * Copyright 2007, Michael Lum <michael.lum [AT] utstar.com>
 * In association with UTStarcom Inc.
 *
 * 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 <math.h>

#include <epan/packet.h>
#include <epan/expert.h>
#include <epan/tfs.h>
#include <epan/unit_strings.h>
#include <wsutil/array.h>

void proto_register_ansi_801(void);
void proto_reg_handoff_ansi_801(void);

static const char *ansi_proto_name = "ANSI IS-801 (Location Services (PLD))";
static const char *ansi_proto_name_short = "IS-801";

#define ANSI_801_FORWARD  0
#define ANSI_801_REVERSE  1


/* Initialize the subtree pointers */
static int ett_ansi_801;
static int ett_gps;
static int ett_loc;

/* Initialize the protocol and registered fields */
static int proto_ansi_801;
static int hf_ansi_801_for_req_type;
static int hf_ansi_801_for_rsp_type;
static int hf_ansi_801_rev_req_type;
static int hf_ansi_801_rev_rsp_type;
static int hf_ansi_801_for_sess_tag;
static int hf_ansi_801_rev_sess_tag;
static int hf_ansi_801_sess_tag;

static int hf_ansi_801_time_ref_cdma;
static int hf_ansi_801_lat;
static int hf_ansi_801_long;
static int hf_ansi_801_loc_uncrtnty_ang;
static int hf_ansi_801_loc_uncrtnty_a;
static int hf_ansi_801_loc_uncrtnty_p;
static int hf_ansi_801_fix_type;
static int hf_ansi_801_velocity_incl;
static int hf_ansi_801_velocity_hor;
static int hf_ansi_801_heading;
static int hf_ansi_801_velocity_ver;
static int hf_ansi_801_clock_incl;
static int hf_ansi_801_clock_bias;
static int hf_ansi_801_clock_drift;
static int hf_ansi_801_height_incl;
static int hf_ansi_801_height;
static int hf_ansi_801_loc_uncrtnty_v;
static int hf_ansi_801_reserved_bits;

static int hf_ansi_801_bad_sv_present;
static int hf_ansi_801_num_bad_sv;
static int hf_ansi_801_bad_sv_prn_num;
static int hf_ansi_801_dopp_req;
static int hf_ansi_801_add_dopp_req;
static int hf_ansi_801_code_ph_par_req;
static int hf_ansi_801_az_el_req;

static int hf_ansi_801_pref_resp_qual;
static int hf_ansi_801_num_fixes;
static int hf_ansi_801_t_betw_fixes;
static int hf_ansi_801_offset_req;

/* Generated from convert_proto_tree_add_text.pl */
static int hf_ansi_801_for_message_number_responsesF0;
static int hf_ansi_801_apdc_id;
static int hf_ansi_801_num_sv_p32;
static int hf_ansi_801_regulatory_services_indicator;
static int hf_ansi_801_session_source;
static int hf_ansi_801_reserved8_E0;
static int hf_ansi_801_action_time;
static int hf_ansi_801_rev_message_number_responsesF0;
static int hf_ansi_801_reserved24_3;
static int hf_ansi_801_cancellation_type;
static int hf_ansi_801_gps_navigation_message_bits;
static int hf_ansi_801_num_dr_p;
static int hf_ansi_801_rev_message_number_requests8;
static int hf_ansi_801_reserved8_F0;
static int hf_ansi_801_for_req_loc_clock_correction_for_gps_time;
static int hf_ansi_801_for_response_length;
static int hf_ansi_801_session_end;
static int hf_ansi_801_reserved8_1F;
static int hf_ansi_801_part_num;
static int hf_ansi_801_dr_size;
static int hf_ansi_801_reserved_24_700;
static int hf_ansi_801_for_message_number_responses0F;
static int hf_ansi_801_rev_message_number_requests16;
static int hf_ansi_801_lcc_capable_using_location_assistance_spherical;
static int hf_ansi_801_part_num32;
static int hf_ansi_801_part_num16;
static int hf_ansi_801_reserved8_07;
static int hf_ansi_801_reserved24_1;
static int hf_ansi_801_reserved_24_F80000;
static int hf_ansi_801_extended_base_station_almanac;
static int hf_ansi_801_no_outstanding_request_element;
static int hf_ansi_801_for_request_length;
static int hf_ansi_801_week_num;
static int hf_ansi_801_total_parts16;
static int hf_ansi_801_pd_message_type;
static int hf_ansi_801_total_parts32;
static int hf_ansi_801_alpha_and_beta_parameters;
static int hf_ansi_801_lcc_using_gps_ephemeris_assistance;
static int hf_ansi_801_rev_request_length;
static int hf_ansi_801_reserved8_7F;
static int hf_ansi_801_unsolicited_response_indicator;
static int hf_ansi_801_autonomous_location_calculation_capable;
static int hf_ansi_801_gps_almanac_correction;
static int hf_ansi_801_total_parts;
static int hf_ansi_801_session_start;
static int hf_ansi_801_ref_bit_num;
static int hf_ansi_801_aflt_lcc;
static int hf_ansi_801_reject_reason;
static int hf_ansi_801_gps_ephemeris;
static int hf_ansi_801_pre_programmed_location;
static int hf_ansi_801_rev_response_length;
static int hf_ansi_801_afltc_id;
static int hf_ansi_801_rev_req_loc_height_information;
static int hf_ansi_801_reserved8_01;
static int hf_ansi_801_pilot_ph_cap;
static int hf_ansi_801_gps_acquisition_assistance;
static int hf_ansi_801_coordinate_type_requested;
static int hf_ansi_801_gps_almanac;
static int hf_ansi_801_rev_req_loc_velocity_information;
static int hf_ansi_801_gps_autonomous_acquisition_capable;
static int hf_ansi_801_num_sv_p16;
static int hf_ansi_801_mob_sys_t_offset;
static int hf_ansi_801_desired_pilot_phase_resolution;
static int hf_ansi_801_for_req_loc_velocity_information;
static int hf_ansi_801_reserved8_0F;
static int hf_ansi_801_hybrid_gps_and_aflt_lcc;
static int hf_ansi_801_gps_acq_cap;
static int hf_ansi_801_gps_sensitivity_assistance;
static int hf_ansi_801_ms_ls_rev;
static int hf_ansi_801_reject_request_type;
static int hf_ansi_801_ms_mode;
static int hf_ansi_801_bs_ls_rev;
static int hf_ansi_801_ref_pn;
static int hf_ansi_801_rev_message_number_responses0F;
static int hf_ansi_801_for_req_loc_height_information;
static int hf_ansi_801_gps_capability_indicator;
static int hf_ansi_801_rev_req_loc_clock_correction_for_gps_time;
static int hf_ansi_801_data_records;
static int hf_ansi_801_for_message_number_requests8;
static int hf_ansi_801_subframes_4_and_5;
static int hf_ansi_801_use_action_time_indicator;
static int hf_ansi_801_lcc_using_gps_almanac_assistance;
static int hf_ansi_801_lcc_using_gps_almanac_correction;
static int hf_ansi_801_pd_message_len;
static int hf_ansi_801_lcc_using_location_assistance_cartesian;
static int hf_ansi_801_for_message_number_requests16;
static int hf_ansi_801_reserved_24_7;
static int hf_ansi_801_loc_calc_cap;
static int hf_ansi_801_toa;
static int hf_ansi_801_data;
static int hf_ansi_801_proprietary_data;
static int hf_ansi_801_time_ref_ms;
static int hf_ansi_801_time_of_almanac;
static int hf_ansi_801_gps_week_number;


static expert_field ei_ansi_801_extraneous_data;
static expert_field ei_ansi_801_short_data;
static expert_field ei_ansi_801_unexpected_length;


static dissector_handle_t ansi_801_handle;

/* PARAM FUNCTIONS */

#define EXTRANEOUS_DATA_CHECK(edc_len, edc_max_len)     \
  if ((edc_len) > (edc_max_len))         \
  {               \
    proto_tree_add_expert(tree, pinfo, &ei_ansi_801_extraneous_data, tvb, \
            offset, (edc_len) - (edc_max_len)); \
  }

#define SHORT_DATA_CHECK(sdc_len, sdc_min_len)        \
  if ((sdc_len) < (sdc_min_len))         \
  {               \
    proto_tree_add_expert(tree, pinfo, &ei_ansi_801_short_data, tvb,  \
            offset, (sdc_len)); \
    return;             \
  }

#define EXACT_DATA_CHECK(edc_len, edc_eq_len)       \
  if ((edc_len) != (edc_eq_len))          \
  {               \
    proto_tree_add_expert(tree, pinfo, &ei_ansi_801_unexpected_length, tvb, \
            offset, (edc_len)); \
    return;             \
  }


/*
 * Table 3.2-4 for PD_MSG_TYPE = '0000000'
 */
static const value_string for_req_type_strings[] = {
  { 0,  "Reserved" },
  { 1,  "Request Location Response" },
  { 2,  "Request MS Information" },
  { 3,  "Request Autonomous Measurement Weighting Factors" },
  { 4,  "Request Pseudorange Measurement" },
  { 5,  "Request Pilot Phase Measurement" },
  { 6,  "Request Time Offset Measurement" },
  { 7,  "Request Cancellation" },
  { 0, NULL },
};
#define NUM_FOR_REQ_TYPE array_length(for_req_type_strings)
static int ett_for_req_type[NUM_FOR_REQ_TYPE];

static const value_string for_rsp_type_strings[] = {
  { 0,  "Reject" },
  { 2,  "Provide BS Capabilities" },
  { 4,  "Provide GPS Acquisition Assistance" },
  { 6,  "Provide GPS Location Assistance Spherical Coordinates" },
  { 7,  "Provide GPS Location Assistance Cartesian Coordinates" },
  { 5,  "Provide GPS Sensitivity Assistance" },
  { 3,  "Provide Base Station Almanac" },
  { 8,  "Provide GPS Almanac" },
  { 9,  "Provide GPS Ephemeris" },
  { 10, "Provide GPS Navigation Message Bits" },
  { 1,  "Provide Location Response" },
  { 11, "Provide GPS Almanac Correction" },
  { 12, "Provide GPS Satellite Health Information" },
  { 0, NULL },
};
#define NUM_FOR_RSP_TYPE array_length(for_rsp_type_strings)
static int ett_for_rsp_type[NUM_FOR_RSP_TYPE];


static const value_string rev_rsp_type_strings[] = {
  { 0,  "Reject" },
  { 2,  "Provide MS Information" },
  { 3,  "Provide Autonomous Measurement Weighting Factors" },
  { 4,  "Provide Pseudorange Measurement" },
  { 5,  "Provide Pilot Phase Measurement" },
  { 1,  "Provide Location Response" },
  { 6,  "Provide Time Offset Measurement" },
  { 7,  "Provide Cancellation Acknowledgement" },
  { 0, NULL },
};
#define NUM_REV_RSP_TYPE array_length(rev_rsp_type_strings)
static int ett_rev_rsp_type[NUM_REV_RSP_TYPE];

/*
 * Table 2.2-5 for PD_MSG_TYPE = '0000000'
 */
static const value_string rev_req_type_strings[] = {
  { 0,  "Reserved" },
  { 2,  "Request BS Capabilities" },
  { 4,  "Request GPS Acquisition Assistance" },
  { 6,  "Request GPS Location Assistance" },
  { 7,  "Reserved" },
  { 5,  "Request GPS Sensitivity Assistance" },
  { 3,  "Request Base Station Almanac" },
  { 8,  "Request GPS Almanac" },
  { 9,  "Request GPS Ephemeris" },
  { 10, "Request GPS Navigation Message Bits" },
  { 1,  "Request Location Response" },
  { 11, "Request GPS Almanac Correction" },
  { 12, "Request GPS Satellite Health Information" },
  { 0, NULL },
};
#define NUM_REV_REQ_TYPE array_length(rev_req_type_strings)
static int ett_rev_req_type[NUM_REV_REQ_TYPE];

static const value_string regulatory_services_indicator_vals[] = {
  { 0,  "No Regulatory service" },
  { 1,  "Emergency service" },
  { 2,  "Reserved" },
  { 3,  "Reserved" },
  { 0, NULL },
};

static const true_false_string tfs_desired_pilot_phase_resolution = { "at least 1/8th PN chip resolution", "at least 1 PN chip resolution" };
static const true_false_string tfs_spherical_cartesian = { "Spherical", "Cartesian" };

static const unit_name_string units_time_of_almanac = { " (in units of 4096 seconds)", NULL };
static const unit_name_string units_gps_week_number = { " (8 least significant bits)", NULL };

static void
for_req_pseudo_meas(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint32_t  saved_offset = offset;

  SHORT_DATA_CHECK(len, 3);

  /* PREF_RESP_QUAL */
  proto_tree_add_item(tree, hf_ansi_801_pref_resp_qual, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_num_fixes, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_t_betw_fixes, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_offset_req, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_reserved_24_7, tvb, offset, 3, ENC_BIG_ENDIAN);
  offset += 3;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);

}

static void
for_req_pilot_ph_meas(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint32_t  saved_offset;

  SHORT_DATA_CHECK(len, 3);

  saved_offset = offset;

  proto_tree_add_item(tree, hf_ansi_801_pref_resp_qual, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_num_fixes, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_t_betw_fixes, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_offset_req, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_desired_pilot_phase_resolution, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_reserved_24_7, tvb, offset, 3, ENC_BIG_ENDIAN);
  offset += 3;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void
for_req_loc_response(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint32_t  saved_offset;

  SHORT_DATA_CHECK(len, 3);

  saved_offset = offset;

  proto_tree_add_item(tree, hf_ansi_801_pref_resp_qual, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_num_fixes, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_t_betw_fixes, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_for_req_loc_height_information, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_for_req_loc_clock_correction_for_gps_time, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_for_req_loc_velocity_information, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_reserved24_3, tvb, offset, 3, ENC_BIG_ENDIAN);
  offset += 3;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void
for_req_time_off_meas(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint8_t oct;
  uint32_t  saved_offset;

  SHORT_DATA_CHECK(len, 1);

  saved_offset = offset;

  oct = tvb_get_uint8(tvb, offset);

  proto_tree_add_item(tree, hf_ansi_801_use_action_time_indicator, tvb, offset, 1, ENC_NA);

  if (oct & 0x80)
  {
    proto_tree_add_item(tree, hf_ansi_801_action_time, tvb, offset, 1, ENC_BIG_ENDIAN);
    proto_tree_add_item(tree, hf_ansi_801_reserved8_01, tvb, offset, 1, ENC_BIG_ENDIAN);
  }
  else
  {
    proto_tree_add_item(tree, hf_ansi_801_reserved8_7F, tvb, offset, 1, ENC_BIG_ENDIAN);
  }
  offset++;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void
for_req_cancel(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint8_t      oct;
  uint32_t     saved_offset;
  const char *str = NULL;

  SHORT_DATA_CHECK(len, 1);

  saved_offset = offset;

  oct = tvb_get_uint8(tvb, offset);

  str = val_to_str_const((oct & 0xf0) >> 4, for_req_type_strings, "Reserved");
  proto_tree_add_uint_format_value(tree, hf_ansi_801_cancellation_type, tvb, offset, 1,
          oct, "(%u) %s", (oct & 0xf0) >> 4, str);

  proto_tree_add_item(tree, hf_ansi_801_reserved8_0F, tvb, offset, 1, ENC_BIG_ENDIAN);
  offset++;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void
for_reject(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint8_t      oct;
  uint32_t     saved_offset;
  const char *str = NULL;

  saved_offset = offset;

  SHORT_DATA_CHECK(len, 1);

  oct = tvb_get_uint8(tvb, offset);
  str = val_to_str_const((oct & 0xf0) >> 4, rev_req_type_strings, "Reserved");

  proto_tree_add_uint_format_value(tree, hf_ansi_801_reject_request_type, tvb, offset, 1, oct,
          "(%u) %s", (oct & 0xf0) >> 4, str);

  switch ((oct & 0x0e) >> 1)
  {
  case 0x00: str = "Capability not supported by the base station"; break;
  case 0x01: str = "Capability normally supported by the base station but temporarily not available or not enabled"; break;
  default: str = "Reserved"; break;
  }

  proto_tree_add_uint_format_value(tree, hf_ansi_801_reject_reason, tvb, offset, 1, oct, "%s", str);
  proto_tree_add_item(tree, hf_ansi_801_reserved8_01, tvb, offset, 1, ENC_BIG_ENDIAN);
  offset++;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void
for_pr_bs_cap(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint8_t oct;
  uint32_t  saved_offset;

  saved_offset = offset;

  SHORT_DATA_CHECK(len, 2);

  proto_tree_add_item(tree, hf_ansi_801_bs_ls_rev, tvb, offset, 1, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_gps_capability_indicator, tvb, offset, 1, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_afltc_id, tvb, offset, 1, ENC_BIG_ENDIAN);
  offset++;

  oct = tvb_get_uint8(tvb, offset);
  if (oct == 0x00)
  {
    proto_tree_add_uint_format(tree, hf_ansi_801_apdc_id, tvb, offset, 1, 0,
            "APDC_ID: Autonomous position determination capability indicator: None");
  }
  else
  {
    proto_tree_add_item(tree, hf_ansi_801_apdc_id, tvb, offset, 1, ENC_BIG_ENDIAN);
  }

  offset++;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void
for_pr_gps_sense_ass(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint32_t  saved_offset;

  saved_offset = offset;

  SHORT_DATA_CHECK(len, 4);

  proto_tree_add_item(tree, hf_ansi_801_ref_bit_num, tvb, offset, 2, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_num_dr_p, tvb, offset, 2, ENC_BIG_ENDIAN);
  offset += 2;

  proto_tree_add_item(tree, hf_ansi_801_dr_size, tvb, offset, 3, ENC_BIG_ENDIAN);
  offset++;

  proto_tree_add_item(tree, hf_ansi_801_part_num, tvb, offset, 2, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_total_parts, tvb, offset, 2, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_data_records, tvb, offset, 2, ENC_BIG_ENDIAN);
  offset++;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void
for_pr_gps_almanac(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint32_t  saved_offset = offset;
  int * const fields[] = {
    &hf_ansi_801_num_sv_p32,
    &hf_ansi_801_week_num,
    &hf_ansi_801_toa,
    &hf_ansi_801_part_num32,
    &hf_ansi_801_total_parts32,
    NULL
  };

  SHORT_DATA_CHECK(len, 4);

    proto_tree_add_bitmask_list(tree, tvb, offset, 4, fields, ENC_BIG_ENDIAN);
  offset += 4;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void
for_pr_gps_nav_msg_bits(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint32_t  saved_offset = offset;
  int * const fields[] = {
    &hf_ansi_801_num_sv_p16,
    &hf_ansi_801_part_num16,
    &hf_ansi_801_total_parts16,
    NULL
  };

  SHORT_DATA_CHECK(len, 2);

    proto_tree_add_bitmask_list(tree, tvb, offset, 2, fields, ENC_BIG_ENDIAN);
  offset += 2;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

/*
 * shared for both forward/reverse directions
 */
static const true_false_string ansi_801_fix_type_vals = {
  "3D",
  "2D"
};

static void
pr_loc_response(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint32_t     bit_offset, spare_bits;
  uint32_t     value;
  float        fl_value;
  uint32_t     saved_offset;
  uint64_t     fix_type, velocity_incl, clock_incl, height_incl;
  const char *str = NULL;

  SHORT_DATA_CHECK(len, 11);
  saved_offset = offset;
  bit_offset   = offset << 3;

  /* TIME_REF_CDMA */
  value = tvb_get_bits16(tvb, bit_offset, 14, ENC_BIG_ENDIAN);
  proto_tree_add_uint_bits_format_value(tree, hf_ansi_801_time_ref_cdma, tvb, bit_offset, 14, value * 50,
                ENC_BIG_ENDIAN, "%u frames (0x%04x)", value * 50, value);
  bit_offset += 14;

  /* LAT */
  value = tvb_get_bits32(tvb, bit_offset, 25, ENC_BIG_ENDIAN);
  fl_value = (float)(-90.0 + ((float)value * 180 / 33554432));
  proto_tree_add_float_bits_format_value(tree, hf_ansi_801_lat, tvb, bit_offset, 25, fl_value, ENC_BIG_ENDIAN,
                 "%.5f degrees %s (0x%08x)", fabs(fl_value), fl_value < 0 ? "South" : "North", value);
  bit_offset += 25;

  /* LONG */
  value    = tvb_get_bits32(tvb, bit_offset, 26, ENC_BIG_ENDIAN);
  fl_value = (float)(-180.0 + ((float)value * 180 / 33554432));
  proto_tree_add_float_bits_format_value(tree, hf_ansi_801_long, tvb, bit_offset, 26, fl_value, ENC_BIG_ENDIAN,
                 "%.5f degrees %s (0x%08x)", fabs(fl_value), fl_value < 0 ? "West" : "East", value);
  bit_offset += 26;

  /* LOC_UNCRTNTY_ANG */
  value    = tvb_get_bits8(tvb, bit_offset, 4);
  fl_value = (float)(5.625 * value);
  proto_tree_add_float_bits_format_value(tree, hf_ansi_801_loc_uncrtnty_ang, tvb, bit_offset, 4, fl_value,
                 ENC_BIG_ENDIAN, "%.5f degrees (0x%02x)", fl_value, value);
  bit_offset += 4;

  /* LOC_UNCRTNTY_A */
  value = tvb_get_bits8(tvb, bit_offset, 5);
  switch (value)
  {
  case 0x1e: str = "> 12288.00 meters"; break;
  case 0x1f: str = "Not computable"; break;
  default:
    fl_value = (float)(0.5f * (1 << (value >> 1)));
    if (value & 0x01)
      fl_value *= 1.5f;
    str = wmem_strdup_printf(pinfo->pool, "%.2f meters", fl_value);
  }
  proto_tree_add_uint_bits_format_value(tree, hf_ansi_801_loc_uncrtnty_a, tvb, bit_offset, 5, value,
                ENC_BIG_ENDIAN, "%s (0x%02x)", str, value);
  bit_offset += 5;

  /* LOC_UNCRTNTY_P */
  value = tvb_get_bits8(tvb, bit_offset, 5);
  switch (value)
  {
  case 0x1e: str = "> 12288.00 meters"; break;
  case 0x1f: str = "Not computable"; break;
  default:
    fl_value = (float)(0.5f * (1 << (value >> 1)));
    if (value & 0x01)
      fl_value *= 1.5f;
    str = wmem_strdup_printf(pinfo->pool, "%.2f meters", fl_value);
  }
  proto_tree_add_uint_bits_format_value(tree, hf_ansi_801_loc_uncrtnty_p, tvb, bit_offset, 5, value,
                ENC_BIG_ENDIAN, "%s (0x%02x)", str, value);
  bit_offset += 5;

  /* FIX_TYPE */
  proto_tree_add_bits_ret_val(tree, hf_ansi_801_fix_type, tvb, bit_offset++, 1, &fix_type, ENC_BIG_ENDIAN);

  /* VELOCITY_INCL */
  proto_tree_add_bits_ret_val(tree, hf_ansi_801_velocity_incl, tvb, bit_offset++, 1, &velocity_incl, ENC_BIG_ENDIAN);


  if(velocity_incl)
  {
    /* VELOCITY_HOR */
    value = tvb_get_bits16(tvb, bit_offset, 9, ENC_BIG_ENDIAN);
    fl_value = (float)(0.25 * value);
    proto_tree_add_float_bits_format_value(tree, hf_ansi_801_velocity_hor, tvb, bit_offset, 9, fl_value,
                   ENC_BIG_ENDIAN, "%.2f m/s (0x%04x)", fl_value, value);
    bit_offset += 9;

    /* HEADING */
    value = tvb_get_bits16(tvb, bit_offset, 10, ENC_BIG_ENDIAN);
    fl_value = (float)value * 360 / 1024;
    proto_tree_add_float_bits_format_value(tree, hf_ansi_801_heading, tvb, bit_offset, 10, fl_value,
                   ENC_BIG_ENDIAN, "%.3f degrees (0x%04x)", fl_value, value);
    bit_offset += 10;

    if(fix_type)
    {
      /* VELOCITY_VER */
      value = tvb_get_bits8(tvb, bit_offset, 8);
      fl_value = (float)(-64 + 0.5 * value);
      proto_tree_add_float_bits_format_value(tree, hf_ansi_801_velocity_ver, tvb, bit_offset, 8, fl_value,
                     ENC_BIG_ENDIAN, "%.1f m/s (0x%02x)", fl_value, value);
      bit_offset += 8;
    }
  }

  /* CLOCK_INCL */
  proto_tree_add_bits_ret_val(tree, hf_ansi_801_clock_incl, tvb, bit_offset++, 1, &clock_incl, ENC_BIG_ENDIAN);

  if(clock_incl)
  {
    /* CLOCK_BIAS */
    value = tvb_get_bits32(tvb, bit_offset, 18, ENC_BIG_ENDIAN);
    proto_tree_add_int_bits_format_value(tree, hf_ansi_801_clock_bias, tvb, bit_offset, 18, (int32_t)value - 13000,
                 ENC_BIG_ENDIAN, "%d ns (0x%06x)", (int32_t)value - 13000, value);
    bit_offset += 18;

    /* CLOCK_DRIFT */
    value = tvb_get_bits16(tvb, bit_offset, 16, ENC_BIG_ENDIAN);
    proto_tree_add_int_bits_format_value(tree, hf_ansi_801_clock_drift, tvb, bit_offset, 16, (int16_t)value,
                 ENC_BIG_ENDIAN, "%d ppb (ns/s) (0x%04x)", (int16_t)value, value);
    bit_offset += 16;
  }

  /* HEIGHT_INCL */
  proto_tree_add_bits_ret_val(tree, hf_ansi_801_height_incl, tvb, bit_offset++, 1, &height_incl, ENC_BIG_ENDIAN);

  if(height_incl)
  {
    /* HEIGHT */
    value = tvb_get_bits16(tvb, bit_offset, 14, ENC_BIG_ENDIAN);
    proto_tree_add_int_bits_format_value(tree, hf_ansi_801_height, tvb, bit_offset, 14, (int32_t)value - 500,
                 ENC_BIG_ENDIAN, "%d m (0x%04x)", (int32_t)value - 500, value);
    bit_offset += 14;

    /* LOC_UNCRTNTY_V */
    value = tvb_get_bits8(tvb, bit_offset, 5);
    switch (value)
    {
    case 0x1e: str = "> 12288.00 meters"; break;
    case 0x1f: str = "Not computable"; break;
    default:
      fl_value = (float)(0.5f * (1 << (value >> 1)));
      if (value & 0x01)
        fl_value *= 1.5f;
      str = wmem_strdup_printf(pinfo->pool, "%.2f meters", fl_value);
    }
    proto_tree_add_uint_bits_format_value(tree, hf_ansi_801_loc_uncrtnty_v, tvb, bit_offset, 5, value,
                  ENC_BIG_ENDIAN, "%s (0x%02x)", str, value);
    bit_offset += 5;
  }

  if(bit_offset & 0x07)
  {
    spare_bits = 8 - (bit_offset & 0x07);
    proto_tree_add_bits_item(tree, hf_ansi_801_reserved_bits, tvb, bit_offset, spare_bits, ENC_BIG_ENDIAN);
    bit_offset += spare_bits;
  }

  offset = bit_offset >> 3;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void
for_pr_loc_response(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  pr_loc_response(tvb, pinfo, tree, len, offset);
}

static void
for_pr_gps_sat_health(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint32_t  bit_offset, spare_bits;
  uint32_t  i;
  uint32_t  saved_offset, num_bad_sv, bad_sv_prn_num;
  uint64_t  bad_sv_present;

  SHORT_DATA_CHECK(len, 1);
  saved_offset = offset;
  bit_offset   = offset << 3;

  /* BAD_SV_PRESENT */
  proto_tree_add_bits_ret_val(tree, hf_ansi_801_bad_sv_present, tvb, bit_offset++, 1, &bad_sv_present, ENC_BIG_ENDIAN);

  if (bad_sv_present)
  {
    /* NUM_BAD_SV */
    num_bad_sv = tvb_get_bits8(tvb, bit_offset, 4) + 1;
    proto_tree_add_uint_bits_format_value(tree, hf_ansi_801_num_bad_sv, tvb, bit_offset, 4, num_bad_sv,
                  ENC_BIG_ENDIAN, "%u", num_bad_sv);
    bit_offset += 4;

    for (i=0; i < num_bad_sv; i++)
    {
      /* BAD_SV_PRN_NUM */
      bad_sv_prn_num = tvb_get_bits8(tvb, bit_offset, 5) + 1;
      proto_tree_add_uint_bits_format_value(tree, hf_ansi_801_bad_sv_prn_num, tvb, bit_offset, 5, bad_sv_prn_num,
                    ENC_BIG_ENDIAN, "%u", bad_sv_prn_num);
      bit_offset += 5;
    }
  }

  if(bit_offset & 0x07)
  {
    spare_bits = 8 - (bit_offset & 0x07);
    proto_tree_add_bits_item(tree, hf_ansi_801_reserved_bits, tvb, bit_offset, spare_bits, ENC_BIG_ENDIAN);
    bit_offset += spare_bits;
  }

  offset = bit_offset >> 3;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void
rev_req_gps_acq_ass(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint32_t  saved_offset;
  uint32_t  bit_offset;

  SHORT_DATA_CHECK(len, 1);
  saved_offset = offset;
  bit_offset   = offset << 3;

  proto_tree_add_bits_item(tree, hf_ansi_801_dopp_req, tvb, bit_offset++, 1, ENC_BIG_ENDIAN);
  proto_tree_add_bits_item(tree, hf_ansi_801_add_dopp_req, tvb, bit_offset++, 1, ENC_BIG_ENDIAN);
  proto_tree_add_bits_item(tree, hf_ansi_801_code_ph_par_req, tvb, bit_offset++, 1, ENC_BIG_ENDIAN);
  proto_tree_add_bits_item(tree, hf_ansi_801_az_el_req, tvb, bit_offset++, 1, ENC_BIG_ENDIAN);
  proto_tree_add_bits_item(tree, hf_ansi_801_reserved_bits, tvb, bit_offset, 4, ENC_BIG_ENDIAN);
  offset++;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void
rev_req_gps_loc_ass(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint32_t saved_offset;

  SHORT_DATA_CHECK(len, 1);

  saved_offset = offset;

  proto_tree_add_item(tree, hf_ansi_801_coordinate_type_requested, tvb, offset, 1, ENC_NA);
  proto_tree_add_item(tree, hf_ansi_801_reserved8_7F, tvb, offset, 1, ENC_BIG_ENDIAN);
  offset++;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void
rev_req_bs_alm(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint32_t saved_offset;

  SHORT_DATA_CHECK(len, 1);

  saved_offset = offset;

  proto_tree_add_item(tree, hf_ansi_801_extended_base_station_almanac, tvb, offset, 1, ENC_NA);
  proto_tree_add_item(tree, hf_ansi_801_reserved8_7F, tvb, offset, 1, ENC_BIG_ENDIAN);
  offset++;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void
rev_req_gps_ephemeris(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint32_t saved_offset;

  SHORT_DATA_CHECK(len, 1);

  saved_offset = offset;

  proto_tree_add_item(tree, hf_ansi_801_alpha_and_beta_parameters, tvb, offset, 1, ENC_NA);
  proto_tree_add_item(tree, hf_ansi_801_reserved8_7F, tvb, offset, 1, ENC_BIG_ENDIAN);
  offset++;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void
rev_req_gps_nav_msg_bits(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint32_t saved_offset;

  SHORT_DATA_CHECK(len, 1);

  saved_offset = offset;

  proto_tree_add_item(tree, hf_ansi_801_subframes_4_and_5, tvb, offset, 1, ENC_NA);
  proto_tree_add_item(tree, hf_ansi_801_reserved8_7F, tvb, offset, 1, ENC_BIG_ENDIAN);

  offset++;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void
rev_req_loc_response(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint32_t saved_offset;

  SHORT_DATA_CHECK(len, 1);

  saved_offset = offset;

  proto_tree_add_item(tree, hf_ansi_801_rev_req_loc_height_information, tvb, offset, 1, ENC_NA);
  proto_tree_add_item(tree, hf_ansi_801_rev_req_loc_clock_correction_for_gps_time, tvb, offset, 1, ENC_NA);
  proto_tree_add_item(tree, hf_ansi_801_rev_req_loc_velocity_information, tvb, offset, 1, ENC_NA);
  proto_tree_add_item(tree, hf_ansi_801_reserved8_1F, tvb, offset, 1, ENC_BIG_ENDIAN);
  offset++;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void
rev_req_gps_alm_correction(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint32_t  saved_offset;

  SHORT_DATA_CHECK(len, 2);

  saved_offset = offset;

  proto_tree_add_item(tree, hf_ansi_801_time_of_almanac, tvb, offset, 1, ENC_NA);

  offset++;
  proto_tree_add_item(tree, hf_ansi_801_gps_week_number, tvb, offset, 1, ENC_NA);

  offset++;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void
rev_reject(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint8_t      oct;
  uint32_t     saved_offset;
  const char *str = NULL;

  saved_offset = offset;

  SHORT_DATA_CHECK(len, 1);

  oct = tvb_get_uint8(tvb, offset);

  str = val_to_str_const((oct & 0xf0) >> 4, for_req_type_strings, "Reserved");

  proto_tree_add_uint_format_value(tree, hf_ansi_801_reject_request_type, tvb, offset, 1, oct,
          "(%u) %s", (oct & 0xf0) >> 4, str);

  switch ((oct & 0x0e) >> 1)
  {
  case 0x00: str = "Capability not supported by the mobile station"; break;
  case 0x01: str = "Capability normally supported by the mobile station but temporarily not available or not enabled"; break;
  default: str = "Reserved"; break;
  }

  proto_tree_add_uint_format_value(tree, hf_ansi_801_reject_reason, tvb, offset, 1,
          oct, "%s", str);

  proto_tree_add_item(tree, hf_ansi_801_reserved8_01, tvb, offset, 1, ENC_BIG_ENDIAN);
  offset++;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void
rev_pr_ms_information(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint32_t     value;
  uint32_t     saved_offset;
  const char *str = NULL;
  proto_item* ti;
  proto_tree *gps_tree, *loc_tree;

  saved_offset = offset;

  SHORT_DATA_CHECK(len, 5);

  value = tvb_get_ntohs(tvb, offset);

  proto_tree_add_item(tree, hf_ansi_801_ms_ls_rev, tvb, offset, 2, ENC_BIG_ENDIAN);

  proto_tree_add_item(tree, hf_ansi_801_ms_mode, tvb, offset, 2, ENC_BIG_ENDIAN);

  switch (value & 0x003f)
  {
  case 0x00: str = "Full Chip Measurement Capability"; break;
  case 0x01: str = "Half Chip Measurement Capability"; break;
  case 0x02: str = "Quarter Chip Measurement Capability"; break;
  case 0x03: str = "Eighth Chip Measurement Capability"; break;
  case 0x04: str = "One Sixteenth Chip Measurement Capability"; break;
  default: str = "Reserved"; break;
  }

  proto_tree_add_uint_format_value(tree, hf_ansi_801_pilot_ph_cap, tvb, offset, 2,
          value, "(%u) %s", value & 0x3f, str);
  offset += 2;

  ti = proto_tree_add_item(tree, hf_ansi_801_gps_acq_cap, tvb, offset, 3, ENC_BIG_ENDIAN);
  gps_tree = proto_item_add_subtree(ti, ett_gps);

  proto_tree_add_item(gps_tree, hf_ansi_801_reserved_24_F80000, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(gps_tree, hf_ansi_801_gps_autonomous_acquisition_capable, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(gps_tree, hf_ansi_801_gps_almanac_correction, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(gps_tree, hf_ansi_801_gps_navigation_message_bits, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(gps_tree, hf_ansi_801_gps_ephemeris, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(gps_tree, hf_ansi_801_gps_almanac, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(gps_tree, hf_ansi_801_gps_sensitivity_assistance, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(gps_tree, hf_ansi_801_gps_acquisition_assistance, tvb, offset, 3, ENC_BIG_ENDIAN);

  ti = proto_tree_add_item(tree, hf_ansi_801_loc_calc_cap, tvb, offset, 3, ENC_BIG_ENDIAN);
  loc_tree = proto_item_add_subtree(ti, ett_loc);

  proto_tree_add_item(loc_tree, hf_ansi_801_pre_programmed_location, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(loc_tree, hf_ansi_801_reserved_24_700, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(loc_tree, hf_ansi_801_hybrid_gps_and_aflt_lcc, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(loc_tree, hf_ansi_801_autonomous_location_calculation_capable, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(loc_tree, hf_ansi_801_lcc_using_gps_almanac_correction, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(loc_tree, hf_ansi_801_lcc_using_gps_ephemeris_assistance, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(loc_tree, hf_ansi_801_lcc_using_gps_almanac_assistance, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(loc_tree, hf_ansi_801_aflt_lcc, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(loc_tree, hf_ansi_801_lcc_using_location_assistance_cartesian, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(loc_tree, hf_ansi_801_lcc_capable_using_location_assistance_spherical, tvb, offset, 3, ENC_BIG_ENDIAN);
  offset += 3;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void
rev_pr_loc_response(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  pr_loc_response(tvb, pinfo, tree, len, offset);
}

static void
rev_pr_time_off_meas(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint32_t  saved_offset;

  saved_offset = offset;

  SHORT_DATA_CHECK(len, 6);

  proto_tree_add_uint_format_value(tree, hf_ansi_801_time_ref_ms, tvb, offset, 3, tvb_get_ntoh24(tvb, offset),
          "The time of validity of the parameters reported in this response element.");
  offset += 3;

  proto_tree_add_item(tree, hf_ansi_801_ref_pn, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_mob_sys_t_offset, tvb, offset, 3, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_reserved24_1, tvb, offset, 3, ENC_BIG_ENDIAN);
  offset += 3;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void
rev_pr_can_ack(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset)
{
  uint8_t      oct;
  uint32_t     saved_offset;
  const char *str;

  saved_offset = offset;

  SHORT_DATA_CHECK(len, 1);

  oct = tvb_get_uint8(tvb, offset);

  str = val_to_str_const((oct & 0xf0) >> 4, for_req_type_strings, "Reserved");
  proto_tree_add_uint_format_value(tree, hf_ansi_801_cancellation_type, tvb, offset, 1, oct,
          "(%u) %s", (oct & 0xf0) >> 4, str);

  proto_tree_add_item(tree, hf_ansi_801_no_outstanding_request_element, tvb, offset, 1, ENC_NA);
  proto_tree_add_item(tree, hf_ansi_801_reserved8_07, tvb, offset, 1, ENC_BIG_ENDIAN);
  offset++;

  EXTRANEOUS_DATA_CHECK(len, offset - saved_offset);
}

static void (*for_req_type_fcn[])(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset) = {
  NULL, /* Reserved */
  NULL, /* no data */ /* Request MS Information */
  NULL, /* no data */ /* Request Autonomous Measurement Weighting Factors */
  for_req_pseudo_meas,  /* Request Pseudorange Measurement */
  for_req_pilot_ph_meas,  /* Request Pilot Phase Measurement */
  for_req_loc_response, /* Request Location Response */
  for_req_time_off_meas,  /* Request Time Offset Measurement */
  for_req_cancel,   /* Request Cancellation */
  NULL, /* NONE */
};

static void (*for_rsp_type_fcn[])(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset) = {
  for_reject,              /* Reject */
  for_pr_bs_cap,           /* Provide BS Capabilities */
  NULL,                    /* Provide GPS Acquisition Assistance */
  NULL,                    /* Provide GPS Location Assistance Spherical Coordinates */
  NULL,                    /* Provide GPS Location Assistance Cartesian Coordinates */
  for_pr_gps_sense_ass,    /* Provide GPS Sensitivity Assistance */
  NULL,                    /* Provide Base Station Almanac */
  for_pr_gps_almanac,      /* Provide GPS Almanac */
  NULL,                    /* Provide GPS Ephemeris */
  for_pr_gps_nav_msg_bits, /* Provide GPS Navigation Message Bits */
  for_pr_loc_response,     /* Provide Location Response */
  NULL,                    /* Provide GPS Almanac Correction */
  for_pr_gps_sat_health,   /* Provide GPS Satellite Health Information */
  NULL,                    /* NONE */
};

static void (*rev_req_type_fcn[])(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset) = {
  NULL, /* Reserved */
  NULL,   /* no data */   /* Request BS Capabilities */
  rev_req_gps_acq_ass,    /* Request GPS Acquisition Assistance */
  rev_req_gps_loc_ass,    /* Request GPS Location Assistance */
  NULL, /* Reserved */
  NULL,   /* no data */   /* Request GPS Sensitivity Assistance */
  rev_req_bs_alm,     /* Request Base Station Almanac */
  NULL,   /* no data */   /* Request GPS Almanac */
  rev_req_gps_ephemeris,    /* Request GPS Ephemeris */
  rev_req_gps_nav_msg_bits, /* Request GPS Navigation Message Bits */
  rev_req_loc_response,   /* Request Location Response */
  rev_req_gps_alm_correction, /* Request GPS Almanac Correction */
  NULL,   /* no data */   /* Request GPS Satellite Health Information */
  NULL, /* NONE */
};

static void (*rev_rsp_type_fcn[])(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned len, uint32_t offset) = {
  rev_reject,            /* Reject */
  rev_pr_ms_information, /* Provide MS Information */
  NULL,                  /* Provide Autonomous Measurement Weighting Factors */
  NULL,                  /* Provide Pseudorange Measurement */
  NULL,                  /* Provide Pilot Phase Measurement */
  rev_pr_loc_response,   /* Provide Location Response */
  rev_pr_time_off_meas,  /* Provide Time Offset Measurement */
  rev_pr_can_ack,        /* Provide Cancellation Acknowledgement */
  NULL,                  /* NONE */
};

static void
for_request(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, uint32_t *offset_p, uint8_t pd_msg_type)
{
  uint32_t     offset;
  uint8_t      oct;
  const char *str = NULL;
  int          idx;
  proto_tree  *subtree;
  proto_item  *item;

  offset = *offset_p;
  oct    = tvb_get_uint8(tvb, offset);

  if (pd_msg_type == 0x00)
  {
    proto_tree_add_item(tree, hf_ansi_801_reserved8_F0, tvb, offset, 1, ENC_BIG_ENDIAN);

    str = try_val_to_str_idx(oct & 0x0f, for_req_type_strings, &idx);
    if (str == NULL)
    {
      return;
    }

    item = proto_tree_add_uint_format_value(tree, hf_ansi_801_for_req_type, tvb, offset, 1,
              oct & 0x0f, "%s (%u)", str, oct & 0x0f);
  }
  else
  {
    /* TBD */
    /*
     * It is unclear from TIA-801-A how this was meant to be decoded.
     * Are the elements supposed to be byte aligned?
     */
    return;
  }

  subtree = proto_item_add_subtree(item, ett_for_req_type[idx]);

  offset++;
  oct = tvb_get_uint8(tvb, offset);

  proto_tree_add_item(subtree, hf_ansi_801_for_request_length, tvb, offset, 1, ENC_BIG_ENDIAN);
  offset++;

  if (oct > 0)
  {
    if (for_req_type_fcn[idx] != NULL)
    {
      (*for_req_type_fcn[idx])(tvb, pinfo, subtree, oct, offset);
    }
    else
    {
      proto_tree_add_item(subtree, hf_ansi_801_data, tvb, offset, oct, ENC_NA);
    }
  }

  *offset_p = offset + oct;
}

static void
for_response(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, uint32_t *offset_p)
{
  uint32_t     offset;
  uint8_t      oct;
  const char *str = NULL;
  int          idx;
  proto_tree  *subtree;
  proto_item  *item;

  offset = *offset_p;
  oct    = tvb_get_uint8(tvb, offset);

  proto_tree_add_item(tree, hf_ansi_801_reserved8_E0, tvb, offset, 1, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_unsolicited_response_indicator, tvb, offset, 1, ENC_NA);

  str = try_val_to_str_idx(oct & 0x0f, for_rsp_type_strings, &idx);

  if (str == NULL)
  {
    return;
  }

  item = proto_tree_add_uint_format_value(tree, hf_ansi_801_for_rsp_type, tvb, offset, 1,
            oct & 0x0f, "%s (%u)", str, oct & 0x0f);
  subtree = proto_item_add_subtree(item, ett_for_rsp_type[idx]);

  offset++;
  oct = tvb_get_uint8(tvb, offset);

  proto_tree_add_item(subtree, hf_ansi_801_for_response_length, tvb, offset, 1, ENC_BIG_ENDIAN);

  offset++;

  if (for_rsp_type_fcn[idx] != NULL)
  {
    (*for_rsp_type_fcn[idx])(tvb, pinfo, subtree, oct, offset);
  }
  else
  {
    proto_tree_add_item(subtree, hf_ansi_801_data, tvb, offset, oct, ENC_NA);
  }

  *offset_p = offset + oct;
}

static void
rev_request(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, uint32_t *offset_p, uint8_t pd_msg_type)
{
  uint32_t     offset;
  uint8_t      oct;
  const char *str = NULL;
  int          idx;
  proto_tree  *subtree;
  proto_item  *item;

  offset = *offset_p;
  oct    = tvb_get_uint8(tvb, offset);

  if (pd_msg_type == 0x00)
  {
    proto_tree_add_item(tree, hf_ansi_801_reserved8_F0, tvb, offset, 1, ENC_BIG_ENDIAN);

    str = try_val_to_str_idx(oct & 0x0f, rev_req_type_strings, &idx);
    if (str == NULL)
    {
      return;
    }

    item = proto_tree_add_uint_format_value(tree, hf_ansi_801_rev_req_type, tvb, offset, 1,
              oct & 0x0f, "%s (%u)", str, oct & 0x0f);
  }
  else
  {
    /* TBD */
    /*
     * It is unclear from TIA-801-A how this was meant to be decoded.
     * Are the elements supposed to be byte aligned?
     */
    return;
  }

  subtree = proto_item_add_subtree(item, ett_rev_req_type[idx]);

  offset++;
  oct = tvb_get_uint8(tvb, offset);

  proto_tree_add_item(subtree, hf_ansi_801_rev_request_length, tvb, offset, 1, ENC_BIG_ENDIAN);

  offset++;

  if (rev_req_type_fcn[idx] != NULL)
  {
    (*rev_req_type_fcn[idx])(tvb, pinfo, subtree, oct, offset);
  }
  else
  {
    proto_tree_add_item(subtree, hf_ansi_801_data, tvb, offset, oct, ENC_NA);
  }

  *offset_p = offset + oct;
}

static void
rev_response(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, uint32_t *offset_p)
{
  uint32_t     offset;
  uint8_t      oct;
  const char *str = NULL;
  int          idx;
  proto_tree  *subtree;
  proto_item  *item;

  offset = *offset_p;
  oct    = tvb_get_uint8(tvb, offset);

  proto_tree_add_item(tree, hf_ansi_801_reserved8_E0, tvb, offset, 1, ENC_BIG_ENDIAN);
  proto_tree_add_item(tree, hf_ansi_801_unsolicited_response_indicator, tvb, offset, 1, ENC_NA);

  str = try_val_to_str_idx(oct & 0x0f, rev_rsp_type_strings, &idx);

  if (str == NULL)
  {
    return;
  }

  item = proto_tree_add_uint_format_value(tree, hf_ansi_801_rev_rsp_type, tvb, offset, 1,
            oct & 0x0f, "%s (%u)", str, oct & 0x0f);
  subtree = proto_item_add_subtree(item, ett_rev_rsp_type[idx]);
  offset++;

  oct = tvb_get_uint8(tvb, offset);

  proto_tree_add_item(subtree, hf_ansi_801_rev_response_length, tvb, offset, 1, ENC_BIG_ENDIAN);

  offset++;

  if (rev_rsp_type_fcn[idx] != NULL)
  {
    (*rev_rsp_type_fcn[idx])(tvb, pinfo, subtree, oct, offset);
  }
  else
  {
    proto_tree_add_item(subtree, hf_ansi_801_data, tvb, offset, oct, ENC_NA);
  }

  *offset_p = offset + oct;
}

static void
dissect_ansi_801_for_message(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
  uint32_t     value;
  uint32_t     offset;
  uint8_t      oct, num_req, num_rsp, pd_msg_type;
  unsigned     rem_len;
  const char *str = NULL;
  proto_item  *hidden_item;

  offset = 0;

  proto_tree_add_item(tree, hf_ansi_801_session_start, tvb, offset, 1, ENC_NA);
  proto_tree_add_item(tree, hf_ansi_801_session_end, tvb, offset, 1, ENC_NA);
  proto_tree_add_item(tree, hf_ansi_801_session_source, tvb, offset, 1, ENC_NA);
  proto_tree_add_item(tree, hf_ansi_801_for_sess_tag, tvb, offset, 1, ENC_BIG_ENDIAN);

  hidden_item = proto_tree_add_item(tree, hf_ansi_801_sess_tag, tvb, offset, 1, ENC_BIG_ENDIAN);
  proto_item_set_hidden(hidden_item);

  offset++;
  oct = tvb_get_uint8(tvb, offset);
  pd_msg_type = oct;

  switch (pd_msg_type)
  {
  case 0x00: str = "Position Determination Data Message"; break;
  case 0x01: str = "Position Determination Data Message"; break;
  case 0xff: str = "Reserved"; break;
  default:
    if (pd_msg_type < 0xc0)
    {
      str = "Reserved for future standardization";
    }
    else
    {
      str = "Available for manufacturer-specific Position Determination "
          "Data Message definition as specified in TSB-58";
    }
    break;
  }

  proto_tree_add_uint_format_value(tree, hf_ansi_801_pd_message_type, tvb, offset, 1, pd_msg_type,
          "%s (%u)", str, pd_msg_type);

  offset++;

  if ((pd_msg_type != 0x00) &&
      (pd_msg_type != 0x01))
  {
    proto_tree_add_item(tree, hf_ansi_801_proprietary_data, tvb, offset, -1, ENC_NA);
    return;
  }

  if (pd_msg_type == 0x01)
  {
    value = tvb_get_ntohs(tvb, offset);

    proto_tree_add_item(tree, hf_ansi_801_pd_message_len, tvb, offset, 2, ENC_BIG_ENDIAN);
    proto_tree_add_item(tree, hf_ansi_801_regulatory_services_indicator, tvb, offset, 2, ENC_BIG_ENDIAN);

    num_req = value & 0x000f;

    proto_tree_add_item(tree, hf_ansi_801_for_message_number_requests16, tvb, offset, 2, ENC_BIG_ENDIAN);
    offset += 2;

    oct = tvb_get_uint8(tvb, offset);
    num_rsp = oct & 0xf0;

    proto_tree_add_item(tree, hf_ansi_801_for_message_number_responsesF0, tvb, offset, 1, ENC_BIG_ENDIAN);
    offset++;
  }
  else
  {
    oct = tvb_get_uint8(tvb, offset);

    num_req = (oct & 0xf0) >> 4;
    num_rsp = oct & 0x0f;

    proto_tree_add_item(tree, hf_ansi_801_for_message_number_requests8, tvb, offset, 1, ENC_BIG_ENDIAN);
    proto_tree_add_item(tree, hf_ansi_801_for_message_number_responses0F, tvb, offset, 1, ENC_BIG_ENDIAN);
  }

  offset++;
  rem_len = tvb_reported_length_remaining(tvb, offset);

  while ((num_req > 0) &&
         (rem_len >= 2))
  {
    for_request(tvb, pinfo, tree, &offset, pd_msg_type);

    rem_len = tvb_reported_length_remaining(tvb, offset);
    num_req--;
  }

  if (num_req != 0)
  {
    proto_tree_add_expert(tree, pinfo, &ei_ansi_801_short_data, tvb, offset, -1);
    return;
  }

  while ((num_rsp > 0) &&
         (rem_len >= 2))
  {
    for_response(tvb, pinfo, tree, &offset);

    rem_len = tvb_reported_length_remaining(tvb, offset);
    num_rsp--;
  }

  if (num_rsp != 0)
  {
    proto_tree_add_expert(tree, pinfo, &ei_ansi_801_short_data, tvb, offset, -1);
    return;
  }

  if (rem_len > 0)
  {
    proto_tree_add_expert(tree, pinfo, &ei_ansi_801_extraneous_data, tvb, offset, rem_len);
  }
}

static void
dissect_ansi_801_rev_message(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
  uint32_t     value;
  uint32_t     offset;
  uint8_t      oct, num_req, num_rsp, pd_msg_type;
  unsigned     rem_len;
  const char *str = NULL;
  proto_item  *hidden_item;

  offset = 0;

  proto_tree_add_item(tree, hf_ansi_801_session_start, tvb, offset, 1, ENC_NA);
  proto_tree_add_item(tree, hf_ansi_801_session_end, tvb, offset, 1, ENC_NA);
  proto_tree_add_item(tree, hf_ansi_801_session_source, tvb, offset, 1, ENC_NA);
  proto_tree_add_item(tree, hf_ansi_801_rev_sess_tag, tvb, offset, 1, ENC_BIG_ENDIAN);

  hidden_item = proto_tree_add_item(tree, hf_ansi_801_sess_tag, tvb, offset, 1, ENC_BIG_ENDIAN);
  proto_item_set_hidden(hidden_item);

  offset++;
  oct = tvb_get_uint8(tvb, offset);
  pd_msg_type = oct;

  switch (pd_msg_type)
  {
  case 0x00: str = "Position Determination Data Message"; break;
  case 0x01: str = "Position Determination Data Message"; break;
  case 0xff: str = "Reserved"; break;
  default:
    if (pd_msg_type < 0xc0)
    {
      str = "Reserved for future standardization";
    }
    else
    {
      str = "Available for manufacturer-specific Position Determination "
        "Data Message definition as specified in TSB-58";
    }
    break;
  }

  proto_tree_add_uint_format_value(tree, hf_ansi_801_pd_message_type, tvb, offset, 1, pd_msg_type,
          "%s (%u)", str, pd_msg_type);
  offset++;

  if ((pd_msg_type != 0x00) &&
      (pd_msg_type != 0x01))
  {
    proto_tree_add_item(tree, hf_ansi_801_proprietary_data, tvb, offset, -1, ENC_NA);
    return;
  }

  if (pd_msg_type == 0x01)
  {
    value = tvb_get_ntohs(tvb, offset);

    proto_tree_add_item(tree, hf_ansi_801_pd_message_len, tvb, offset, 2, ENC_BIG_ENDIAN);
    proto_tree_add_item(tree, hf_ansi_801_regulatory_services_indicator, tvb, offset, 2, ENC_BIG_ENDIAN);

    num_req = value & 0x000f;

    proto_tree_add_item(tree, hf_ansi_801_rev_message_number_requests16, tvb, offset, 2, ENC_BIG_ENDIAN);
    offset += 2;

    oct = tvb_get_uint8(tvb, offset);
    num_rsp = oct & 0xf0;

    proto_tree_add_item(tree, hf_ansi_801_rev_message_number_responsesF0, tvb, offset, 1, ENC_BIG_ENDIAN);
    offset++;
  }
  else
  {
    oct = tvb_get_uint8(tvb, offset);

    num_req = (oct & 0xf0) >> 4;
    num_rsp = oct & 0x0f;

    proto_tree_add_item(tree, hf_ansi_801_rev_message_number_requests8, tvb, offset, 1, ENC_BIG_ENDIAN);
    proto_tree_add_item(tree, hf_ansi_801_rev_message_number_responses0F, tvb, offset, 1, ENC_BIG_ENDIAN);
    offset++;
  }

  rem_len = tvb_reported_length_remaining(tvb, offset);

  while ((num_req > 0) &&
         (rem_len >= 2))
  {
    rev_request(tvb, pinfo, tree, &offset, pd_msg_type);

    rem_len = tvb_reported_length_remaining(tvb, offset);
    num_req--;
  }

  if (num_req != 0)
  {
    proto_tree_add_expert(tree, pinfo, &ei_ansi_801_short_data, tvb, offset, -1);
    return;
  }

  while ((num_rsp > 0) &&
         (rem_len >= 2))
  {
    rev_response(tvb, pinfo, tree, &offset);

    rem_len = tvb_reported_length_remaining(tvb, offset);
    num_rsp--;
  }

  if (num_rsp != 0)
  {
    proto_tree_add_expert(tree, pinfo, &ei_ansi_801_short_data, tvb, offset, -1);
    return;
  }

  if (rem_len > 0)
  {
    proto_tree_add_expert(tree, pinfo, &ei_ansi_801_extraneous_data, tvb, offset, rem_len);
  }
}

static int
dissect_ansi_801(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
{
  proto_item *ansi_801_item;
  proto_tree *ansi_801_tree = NULL;

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

  /* In the interest of speed, if "tree" is NULL, don't do any work not
   * necessary to generate protocol tree items.
   */
  if (tree)
  {
    /*
     * create the ansi_801 protocol tree
     */
    ansi_801_item =
      proto_tree_add_protocol_format(tree, proto_ansi_801, tvb, 0, -1,
                   "%s %s Link",
                   ansi_proto_name,
                   (pinfo->match_uint == ANSI_801_FORWARD) ? "Forward" : "Reverse");

    ansi_801_tree =
      proto_item_add_subtree(ansi_801_item, ett_ansi_801);

    if (pinfo->match_uint == ANSI_801_FORWARD)
    {
      dissect_ansi_801_for_message(tvb, pinfo, ansi_801_tree);
    }
    else
    {
      dissect_ansi_801_rev_message(tvb, pinfo, ansi_801_tree);
    }
  }
  return tvb_captured_length(tvb);
}


/* Register the protocol with Wireshark */
void
proto_register_ansi_801(void)
{
  unsigned i;
  int   last_offset;

  /* Setup list of header fields */
  static hf_register_info hf[] = {
    { &hf_ansi_801_for_req_type,
      { "Forward Request Type", "ansi_801.for_req_type",
        FT_UINT8, BASE_DEC, NULL, 0,
        NULL, HFILL }
    },
    { &hf_ansi_801_for_rsp_type,
      { "Forward Response Type", "ansi_801.for_rsp_type",
        FT_UINT8, BASE_DEC, NULL, 0,
        NULL, HFILL }
    },
    { &hf_ansi_801_rev_req_type,
      { "Reverse Request Type", "ansi_801.rev_req_type",
        FT_UINT8, BASE_DEC, NULL, 0,
        NULL, HFILL }
    },
    { &hf_ansi_801_rev_rsp_type,
      { "Reverse Response Type", "ansi_801.rev_rsp_type",
        FT_UINT8, BASE_DEC, NULL, 0,
        NULL, HFILL }
    },
    { &hf_ansi_801_for_sess_tag,
      { "Forward Session Tag", "ansi_801.for_sess_tag",
        FT_UINT8, BASE_DEC, NULL, 0x1f,
        NULL, HFILL }
    },
    { &hf_ansi_801_rev_sess_tag,
      { "Reverse Session Tag", "ansi_801.rev_sess_tag",
        FT_UINT8, BASE_DEC, NULL, 0x1f,
        NULL, HFILL }
    },
    { &hf_ansi_801_sess_tag,
      { "Session Tag", "ansi_801.sess_tag",
        FT_UINT8, BASE_DEC, NULL, 0x1f,
        NULL, HFILL }
    },
    { &hf_ansi_801_time_ref_cdma,
      { "CDMA system time at the time the solution is valid (TIME_REF_CDMA)", "ansi_801.time_ref_cdma",
        FT_UINT32, BASE_DEC, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_lat,
      { "Latitude (LAT)", "ansi_801.lat",
        FT_FLOAT, BASE_NONE, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_long,
      { "Longitude (LONG)", "ansi_801.long",
        FT_FLOAT, BASE_NONE, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_loc_uncrtnty_ang,
      { "Angle of axis with respect to True North for pos uncertainty (LOC_UNCRTNTY_ANG)", "ansi_801.loc_uncrtnty_ang",
        FT_FLOAT, BASE_NONE, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_loc_uncrtnty_a,
      { "Std dev of axis along angle specified for pos uncertainty (LOC_UNCRTNTY_A)", "ansi_801.loc_uncrtnty_a",
        FT_UINT8, BASE_DEC, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_loc_uncrtnty_p,
      { "Std dev of axis perpendicular to angle specified for pos uncertainty (LOC_UNCRTNTY_P)", "ansi_801.loc_uncrtnty_p",
        FT_UINT8, BASE_DEC, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_fix_type,
      { "Fix type (FIX_TYPE)", "ansi_801.fix_type",
        FT_BOOLEAN, BASE_NONE, TFS(&ansi_801_fix_type_vals), 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_velocity_incl,
      { "Velocity information included (VELOCITY_INCL)", "ansi_801.velocity_incl",
        FT_BOOLEAN, BASE_NONE, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_velocity_hor,
      { "Horizontal velocity magnitude (VELOCITY_HOR)", "ansi_801.velocity_hor",
        FT_FLOAT, BASE_NONE, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_heading,
      { "Heading (HEADING)", "ansi_801.heading",
        FT_FLOAT, BASE_NONE, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_velocity_ver,
      { "Vertical velocity (VELOCITY_VER)", "ansi_801.velocity_ver",
        FT_FLOAT, BASE_NONE, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_clock_incl,
      { "Clock information included (CLOCK_INCL)", "ansi_801.clock_incl",
        FT_BOOLEAN, BASE_NONE, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_clock_bias,
      { "Clock bias (CLOCK_BIAS)", "ansi_801.clock_bias",
        FT_INT24, BASE_DEC, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_clock_drift,
      { "Clock drift (CLOCK_DRIFT)", "ansi_801.clock_drift",
        FT_INT16, BASE_DEC, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_height_incl,
      { "Height information included (HEIGHT_INCL)", "ansi_801.height_incl",
        FT_BOOLEAN, BASE_NONE, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_height,
      { "Height (HEIGHT)", "ansi_801.height",
        FT_INT16, BASE_DEC, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_loc_uncrtnty_v,
      { "Std dev of vertical error for pos uncertainty (LOC_UNCRTNTY_V)", "ansi_801.loc_uncrtnty_v",
        FT_UINT8, BASE_DEC, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_reserved_bits,
      { "Reserved bit(s)","ansi_801.reserved_bits",
        FT_UINT8,BASE_DEC, NULL, 0x0,
        NULL, HFILL }
    },
    { &hf_ansi_801_bad_sv_present,
      { "Bad GPS satellites present (BAD_SV_PRESENT)", "ansi_801.bad_sv_present",
        FT_BOOLEAN, BASE_NONE, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_num_bad_sv,
      { "Number of bad GPS satellites (NUM_BAD_SV)", "ansi_801.num_bad_sv",
        FT_UINT8, BASE_DEC, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_bad_sv_prn_num,
      { "Satellite PRN number (SV_PRN_NUM)", "ansi_801.bad_sv_prn_num",
        FT_UINT8, BASE_DEC, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_dopp_req,
      { "Doppler (0th order) term requested (DOPP_REQ)", "ansi_801.dopp_req",
        FT_BOOLEAN, BASE_NONE, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_add_dopp_req,
      { "Additional Doppler terms requested (ADD_DOPP_REQ)", "ansi_801.add_dopp_req",
        FT_BOOLEAN, BASE_NONE, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_code_ph_par_req,
      { "Code phase parameters requested (CODE_PH_PAR_REQ)", "ansi_801.code_ph_par_req",
        FT_BOOLEAN, BASE_NONE, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_az_el_req,
      { "Azimuth and elevation angle requested (AZ_EL_REQ)", "ansi_801.az_el_req",
        FT_BOOLEAN, BASE_NONE, NULL, 0x00,
        NULL, HFILL }
    },
    { &hf_ansi_801_pref_resp_qual,
      { "Preferred response quality (PREF_RESP_QUAL)", "ansi_801.pref_resp_qual",
        FT_UINT24, BASE_DEC, NULL, 0xe00000,
        NULL, HFILL }
    },
    { &hf_ansi_801_num_fixes,
      { "Number of fixes (NUM_FIXES)", "ansi_801.num_fixes",
        FT_UINT24, BASE_DEC, NULL, 0x1fe000,
        NULL, HFILL }
    },
    { &hf_ansi_801_t_betw_fixes,
      { "Time between fixes (T_BETW_FIXES) (in seconds)", "ansi_801.t_betw_fixes",
        FT_UINT24, BASE_DEC, NULL, 0x001fe0,
        NULL, HFILL }
    },
    { &hf_ansi_801_offset_req,
      { "Offset requested (OFFSET_REQ)", "ansi_801.offset_req",
        FT_BOOLEAN, 24, TFS(&tfs_requested_not_requested), 0x000010,
        NULL, HFILL }
    },

    /* Generated from convert_proto_tree_add_text.pl */
    { &hf_ansi_801_desired_pilot_phase_resolution,
      { "Desired pilot phase resolution", "ansi_801.desired_pilot_phase_resolution",
        FT_BOOLEAN, 24, TFS(&tfs_desired_pilot_phase_resolution), 0x000008,
        NULL, HFILL }
    },
    { &hf_ansi_801_reserved_24_7,
      { "Reserved", "ansi_801.reserved",
        FT_UINT24, BASE_HEX, NULL, 0x07,
        NULL, HFILL }
    },
    { &hf_ansi_801_for_req_loc_height_information,
      { "Height information", "ansi_801.height_incl",
        FT_BOOLEAN, 24, TFS(&tfs_requested_not_requested), 0x000010,
        NULL, HFILL }
    },
    { &hf_ansi_801_for_req_loc_clock_correction_for_gps_time,
      { "Clock correction for GPS time", "ansi_801.clock_correction_for_gps_time",
        FT_BOOLEAN, 24, TFS(&tfs_requested_not_requested), 0x000008,
        NULL, HFILL }
    },
    { &hf_ansi_801_for_req_loc_velocity_information,
      { "Velocity information", "ansi_801.velocity_information",
        FT_BOOLEAN, 24, TFS(&tfs_requested_not_requested), 0x000004,
        NULL, HFILL }
    },
    { &hf_ansi_801_reserved24_3,
      { "Reserved", "ansi_801.reserved",
        FT_UINT24, BASE_HEX, NULL, 0x000003,
        NULL, HFILL }
    },
    { &hf_ansi_801_use_action_time_indicator,
      { "Use action time indicator", "ansi_801.use_action_time_indicator",
        FT_BOOLEAN, 8, NULL, 0x80,
        NULL, HFILL }
    },
    { &hf_ansi_801_action_time,
      { "Action time", "ansi_801.action_time",
        FT_UINT8, BASE_DEC, NULL, 0x7E,
        NULL, HFILL }
    },
    { &hf_ansi_801_reserved8_7F,
      { "Reserved", "ansi_801.reserved",
        FT_UINT8, BASE_HEX, NULL, 0x7F,
        NULL, HFILL }
    },
    { &hf_ansi_801_cancellation_type,
      { "Cancellation Type", "ansi_801.cancellation_type",
        FT_UINT8, BASE_DEC, VALS(for_req_type_strings), 0xF0,
        NULL, HFILL }
    },
    { &hf_ansi_801_reserved8_0F,
      { "Reserved", "ansi_801.reserved",
        FT_UINT8, BASE_HEX, NULL, 0x0F,
        NULL, HFILL }
    },
    { &hf_ansi_801_reject_request_type,
      { "Reject request type", "ansi_801.reject_request_type",
        FT_UINT8, BASE_DEC, VALS(rev_req_type_strings), 0xF0,
        NULL, HFILL }
    },
    { &hf_ansi_801_reject_reason,
      { "Reject reason", "ansi_801.reject_reason",
        FT_UINT8, BASE_DEC, NULL, 0x0E,
        NULL, HFILL }
    },
    { &hf_ansi_801_reserved8_01,
      { "Reserved", "ansi_801.reserved",
        FT_UINT8, BASE_HEX, NULL, 0x01,
        NULL, HFILL }
    },
    { &hf_ansi_801_bs_ls_rev,
      { "BS_LS_REV", "ansi_801.bs_ls_rev",
        FT_UINT8, BASE_HEX, NULL, 0xfc,
        NULL, HFILL }
    },
    { &hf_ansi_801_gps_capability_indicator,
      { "GPSC_ID: GPS capability indicator", "ansi_801.gps_capability_indicator",
        FT_UINT8, BASE_DEC, NULL, 0x02,
        NULL, HFILL }
    },
    { &hf_ansi_801_afltc_id,
      { "AFLTC_ID: Advanced forward link trilateration capability indicator", "ansi_801.afltc_id",
        FT_UINT8, BASE_DEC, NULL, 0x01,
        NULL, HFILL }
    },
    { &hf_ansi_801_apdc_id,
      { "APDC_ID: Autonomous position determination capability indicator: Autonomous Location Technology Identifier", "ansi_801.apdc_id",
        FT_UINT8, BASE_DEC, NULL, 0x0,
        NULL, HFILL }
    },
    { &hf_ansi_801_ref_bit_num,
      { "REF_BIT_NUM", "ansi_801.ref_bit_num",
        FT_UINT16, BASE_DEC, NULL, 0xffe0,
        NULL, HFILL }
    },
    { &hf_ansi_801_num_dr_p,
      { "NUM_DR_P: Number of data records in this part", "ansi_801.num_dr_p",
        FT_UINT16, BASE_DEC, NULL, 0x001e,
        NULL, HFILL }
    },
    { &hf_ansi_801_dr_size,
      { "DR_SIZE: Data record size", "ansi_801.dr_size",
        FT_UINT24, BASE_DEC, NULL, 0x0001FE,
        NULL, HFILL }
    },
    { &hf_ansi_801_part_num,
      { "PART_NUM: The part number", "ansi_801.part_num",
        FT_UINT16, BASE_DEC, NULL, 0x01c0,
        NULL, HFILL }
    },
    { &hf_ansi_801_total_parts,
      { "TOTAL_PARTS: Total number of parts", "ansi_801.total_parts",
        FT_UINT16, BASE_DEC, NULL, 0x38,
        NULL, HFILL }
    },
    { &hf_ansi_801_data_records,
      { "Data records", "ansi_801.data_records",
        FT_UINT16, BASE_DEC, NULL, 0x07,
        NULL, HFILL }
    },
    { &hf_ansi_801_num_sv_p32,
      { "NUM_SV_P: Number of satellites in this part", "ansi_801.num_sv_p",
        FT_UINT32, BASE_DEC, NULL, 0xfc000000,
        NULL, HFILL }
    },
    { &hf_ansi_801_week_num,
      { "WEEK_NUM: The GPS week number of the almanac", "ansi_801.week_num",
        FT_UINT32, BASE_DEC, NULL, 0x03fc0000,
        NULL, HFILL }
    },
    { &hf_ansi_801_toa,
      { "TOA: The reference time of the almanac", "ansi_801.toa",
        FT_UINT32, BASE_DEC, NULL, 0x0003fc00,
        NULL, HFILL }
    },
    { &hf_ansi_801_part_num32,
      { "PART_NUM: The part number", "ansi_801.part_num",
        FT_UINT32, BASE_DEC, NULL, 0x000003e0,
        NULL, HFILL }
    },
    { &hf_ansi_801_total_parts32,
      { "TOTAL_PARTS: The total number of parts", "ansi_801.total_parts",
        FT_UINT32, BASE_DEC, NULL, 0x0000001f,
        NULL, HFILL }
    },
    { &hf_ansi_801_num_sv_p16,
      { "NUM_SV_P: Number of satellites in this part", "ansi_801.num_sv_p",
        FT_UINT16, BASE_DEC, NULL, 0xfc00,
        NULL, HFILL }
    },
    { &hf_ansi_801_part_num16,
      { "PART_NUM: The part number", "ansi_801.part_num",
        FT_UINT16, BASE_DEC, NULL, 0x03e0,
        NULL, HFILL }
    },
    { &hf_ansi_801_total_parts16,
      { "TOTAL_PARTS: The total number of parts", "ansi_801.total_parts",
        FT_UINT16, BASE_DEC, NULL, 0x001f,
        NULL, HFILL }
    },
    { &hf_ansi_801_coordinate_type_requested,
      { "Coordinate type requested", "ansi_801.coordinate_type_requested",
        FT_BOOLEAN, 8, TFS(&tfs_spherical_cartesian), 0x80,
        NULL, HFILL }
    },
    { &hf_ansi_801_extended_base_station_almanac,
      { "Extended base station almanac", "ansi_801.extended_base_station_almanac",
        FT_BOOLEAN, 8, TFS(&tfs_requested_not_requested), 0x80,
        NULL, HFILL }
    },
    { &hf_ansi_801_alpha_and_beta_parameters,
      { "Alpha and Beta parameters", "ansi_801.alpha_and_beta_parameters",
        FT_BOOLEAN, 8, TFS(&tfs_requested_not_requested), 0x80,
        NULL, HFILL }
    },
    { &hf_ansi_801_subframes_4_and_5,
      { "Subframes 4 and 5", "ansi_801.subframes_4_and_5",
        FT_BOOLEAN, 8, TFS(&tfs_requested_not_requested), 0x80,
        NULL, HFILL }
    },
    { &hf_ansi_801_rev_req_loc_height_information,
      { "Height information", "ansi_801.height_information",
        FT_BOOLEAN, 8, TFS(&tfs_requested_not_requested), 0x80,
        NULL, HFILL }
    },
    { &hf_ansi_801_rev_req_loc_clock_correction_for_gps_time,
      { "Clock correction for GPS time", "ansi_801.clock_correction_for_gps_time",
        FT_BOOLEAN, 8, TFS(&tfs_requested_not_requested), 0x40,
        NULL, HFILL }
    },
    { &hf_ansi_801_rev_req_loc_velocity_information,
      { "Velocity information", "ansi_801.velocity_information",
        FT_BOOLEAN, 8, TFS(&tfs_requested_not_requested), 0x20,
        NULL, HFILL }
    },
    { &hf_ansi_801_reserved8_1F,
      { "Reserved", "ansi_801.reserved",
        FT_UINT8, BASE_HEX, NULL, 0x1F,
        NULL, HFILL }
    },
    { &hf_ansi_801_ms_ls_rev,
      { "MS_LS_REV", "ansi_801.ms_ls_rev",
        FT_UINT16, BASE_DEC, NULL, 0xfc00,
        NULL, HFILL }
    },
    { &hf_ansi_801_ms_mode,
      { "MS_MODE", "ansi_801.ms_mode",
        FT_UINT16, BASE_DEC, NULL, 0x03c0,
        NULL, HFILL }
    },
    { &hf_ansi_801_pilot_ph_cap,
      { "PILOT_PH_CAP", "ansi_801.pilot_ph_cap",
        FT_UINT16, BASE_DEC, NULL, 0x003f,
        NULL, HFILL }
    },
    { &hf_ansi_801_gps_acq_cap,
      { "GPS_ACQ_CAP", "ansi_801.gps_acq_cap",
        FT_UINT24, BASE_HEX, NULL, 0x000FFF,
        NULL, HFILL }
    },
    { &hf_ansi_801_reserved_24_F80000,
      { "Reserved", "ansi_801.reserved",
        FT_UINT24, BASE_HEX, NULL, 0xf80000,
        NULL, HFILL }
    },
    { &hf_ansi_801_gps_autonomous_acquisition_capable,
      { "GPS Autonomous Acquisition Capable", "ansi_801.gps_autonomous_acquisition_capable",
        FT_BOOLEAN, 24, NULL, 0x040000,
        NULL, HFILL }
    },
    { &hf_ansi_801_gps_almanac_correction,
      { "GPS Almanac Correction", "ansi_801.gps_almanac_correction",
        FT_BOOLEAN, 24, NULL, 0x020000,
        NULL, HFILL }
    },
    { &hf_ansi_801_gps_navigation_message_bits,
      { "GPS Navigation Message Bits", "ansi_801.gps_navigation_message_bits",
        FT_BOOLEAN, 24, NULL, 0x010000,
        NULL, HFILL }
    },
    { &hf_ansi_801_gps_ephemeris,
      { "GPS Ephemeris", "ansi_801.gps_ephemeris",
        FT_BOOLEAN, 24, NULL, 0x008000,
        NULL, HFILL }
    },
    { &hf_ansi_801_gps_almanac,
      { "GPS Almanac", "ansi_801.gps_almanac",
        FT_BOOLEAN, 24, NULL, 0x004000,
        NULL, HFILL }
    },
    { &hf_ansi_801_gps_sensitivity_assistance,
      { "GPS Sensitivity Assistance", "ansi_801.gps_sensitivity_assistance",
        FT_BOOLEAN, 24, NULL, 0x002000,
        NULL, HFILL }
    },
    { &hf_ansi_801_gps_acquisition_assistance,
      { "GPS Acquisition Assistance", "ansi_801.gps_acquisition_assistance",
        FT_BOOLEAN, 24, NULL, 0x001000,
        NULL, HFILL }
    },
    { &hf_ansi_801_loc_calc_cap,
      { "LOC_CALC_CAP", "ansi_801.loc_calc_cap",
        FT_UINT24, BASE_HEX, NULL, 0x000FFF,
        NULL, HFILL }
    },
    { &hf_ansi_801_pre_programmed_location,
      { "Pre-programmed Location", "ansi_801.pre_programmed_location",
        FT_BOOLEAN, 24, NULL, 0x000800,
        NULL, HFILL }
    },
    { &hf_ansi_801_reserved_24_700,
      { "Reserved", "ansi_801.reserved",
        FT_UINT24, BASE_HEX, NULL, 0x000700,
        NULL, HFILL }
    },
    { &hf_ansi_801_hybrid_gps_and_aflt_lcc,
      { "Hybrid GPS and AFLT Location Calculation Capable", "ansi_801.hybrid_gps_and_aflt_lcc",
        FT_BOOLEAN, 24, NULL, 0x000080,
        NULL, HFILL }
    },
    { &hf_ansi_801_autonomous_location_calculation_capable,
      { "Autonomous Location Calculation Capable", "ansi_801.autonomous_lcc",
        FT_BOOLEAN, 24, NULL, 0x000040,
        NULL, HFILL }
    },
    { &hf_ansi_801_lcc_using_gps_almanac_correction,
      { "Location Calculation Capable using GPS Almanac Correction", "ansi_801.lcc_using_gps_almanac_correction",
        FT_BOOLEAN, 24, NULL, 0x000020,
        NULL, HFILL }
    },
    { &hf_ansi_801_lcc_using_gps_ephemeris_assistance,
      { "Location Calculation Capable using GPS Ephemeris Assistance", "ansi_801.lcc_using_gps_ephemeris_assistance",
        FT_BOOLEAN, 24, NULL, 0x000010,
        NULL, HFILL }
    },
    { &hf_ansi_801_lcc_using_gps_almanac_assistance,
      { "Location Calculation Capable using GPS Almanac Assistance", "ansi_801.lcc_using_gps_almanac_assistance",
        FT_BOOLEAN, 24, NULL, 0x000008,
        NULL, HFILL }
    },
    { &hf_ansi_801_aflt_lcc,
      { "Advanced Forward Link Trilateration (AFLT) Location Calculation Capable", "ansi_801.aflt_lcc",
        FT_BOOLEAN, 24, NULL, 0x000004,
        NULL, HFILL }
    },
    { &hf_ansi_801_lcc_using_location_assistance_cartesian,
      { "Location Calculation Capable using Location Assistance - Cartesian", "ansi_801.lcc_using_location_assistance.cartesian",
        FT_BOOLEAN, 24, NULL, 0x000002,
        NULL, HFILL }
    },
    { &hf_ansi_801_lcc_capable_using_location_assistance_spherical,
      { "Location Calculation Capable using Location Assistance - Spherical", "ansi_801.lcc_using_location_assistance.spherical",
        FT_BOOLEAN, 24, NULL, 0x000001,
        NULL, HFILL }
    },
    { &hf_ansi_801_ref_pn,
      { "REF_PN", "ansi_801.ref_pn",
        FT_UINT24, BASE_DEC, NULL, 0xff8000,
        NULL, HFILL }
    },
    { &hf_ansi_801_mob_sys_t_offset,
      { "MOB_SYS_T_OFFSET", "ansi_801.mob_sys_t_offset",
        FT_UINT24, BASE_DEC, NULL, 0x007ffe,
        NULL, HFILL }
    },
    { &hf_ansi_801_reserved24_1,
      { "Reserved", "ansi_801.reserved",
        FT_UINT24, BASE_HEX, NULL, 0x000001,
        NULL, HFILL }
    },
    { &hf_ansi_801_no_outstanding_request_element,
      { "No outstanding request element", "ansi_801.no_outstanding_request_element",
        FT_BOOLEAN, 8, NULL, 0x08,
        NULL, HFILL }
    },
    { &hf_ansi_801_reserved8_07,
      { "Reserved", "ansi_801.reserved",
        FT_UINT8, BASE_HEX, NULL, 0x07,
        NULL, HFILL }
    },
    { &hf_ansi_801_reserved8_F0,
      { "Reserved", "ansi_801.reserved",
        FT_UINT8, BASE_HEX, NULL, 0xF0,
        NULL, HFILL }
    },
    { &hf_ansi_801_for_request_length,
      { "Length", "ansi_801.for_request_length",
        FT_UINT8, BASE_DEC, NULL, 0x0,
        NULL, HFILL }
    },
    { &hf_ansi_801_reserved8_E0,
      { "Reserved", "ansi_801.reserved",
        FT_UINT8, BASE_HEX, NULL, 0xE0,
        NULL, HFILL }
    },
    { &hf_ansi_801_unsolicited_response_indicator,
      { "Unsolicited response indicator", "ansi_801.unsolicited_response_indicator",
        FT_BOOLEAN, 8, NULL, 0x10,
        NULL, HFILL }
    },
    { &hf_ansi_801_for_response_length,
      { "Length", "ansi_801.for_response_length",
        FT_UINT8, BASE_DEC, NULL, 0x0,
        NULL, HFILL }
    },
    { &hf_ansi_801_rev_request_length,
      { "Length", "ansi_801.rev_request_length",
        FT_UINT8, BASE_DEC, NULL, 0x0,
        NULL, HFILL }
    },
    { &hf_ansi_801_rev_response_length,
      { "Length", "ansi_801.rev_response_length",
        FT_UINT8, BASE_DEC, NULL, 0x0,
        NULL, HFILL }
    },
    { &hf_ansi_801_session_start,
      { "Session Start", "ansi_801.session_start",
        FT_BOOLEAN, 8, NULL, 0x80,
        NULL, HFILL }
    },
    { &hf_ansi_801_session_end,
      { "Session End", "ansi_801.session_end",
        FT_BOOLEAN, 8, NULL, 0x40,
        NULL, HFILL }
    },
    { &hf_ansi_801_session_source,
      { "Session Source", "ansi_801.session_source",
        FT_BOOLEAN, 8, NULL, 0x20,
        NULL, HFILL }
    },
    { &hf_ansi_801_pd_message_type,
      { "PD Message Type", "ansi_801.pd_message_type",
        FT_UINT8, BASE_DEC, NULL, 0x0,
        NULL, HFILL }
    },
    { &hf_ansi_801_pd_message_len,
      { "PD Message Length", "ansi_801.pd_message_len",
        FT_UINT16, BASE_DEC, NULL, 0xffc0,
        NULL, HFILL }
    },
    { &hf_ansi_801_regulatory_services_indicator,
      { "Regulatory Services Indicator", "ansi_801.regulatory_services_indicator",
        FT_UINT16, BASE_DEC, VALS(regulatory_services_indicator_vals), 0x0030,
        NULL, HFILL }
    },
    { &hf_ansi_801_for_message_number_requests16,
      { "Number Requests", "ansi_801.for_message_number_requests",
        FT_UINT16, BASE_DEC, NULL, 0x0F,
        NULL, HFILL }
    },
    { &hf_ansi_801_for_message_number_responsesF0,
      { "Number Responses", "ansi_801.for_message_number_responses",
        FT_UINT8, BASE_DEC, NULL, 0xF0,
        NULL, HFILL }
    },
    { &hf_ansi_801_for_message_number_requests8,
      { "Number Requests", "ansi_801.for_message_number_requests",
        FT_UINT8, BASE_DEC, NULL, 0xF0,
        NULL, HFILL }
    },
    { &hf_ansi_801_for_message_number_responses0F,
      { "Number Responses", "ansi_801.for_message_number_responses",
        FT_UINT8, BASE_DEC, NULL, 0x0F,
        NULL, HFILL }
    },
    { &hf_ansi_801_rev_message_number_requests16,
      { "Number Requests", "ansi_801.rev_message_number_requests",
        FT_UINT16, BASE_DEC, NULL, 0x0F,
        NULL, HFILL }
    },
    { &hf_ansi_801_rev_message_number_responsesF0,
      { "Number Responses", "ansi_801.rev_message_number_responses",
        FT_UINT8, BASE_DEC, NULL, 0xF0,
        NULL, HFILL }
    },
    { &hf_ansi_801_rev_message_number_requests8,
      { "Number Requests", "ansi_801.rev_message_number_requests",
        FT_UINT8, BASE_DEC, NULL, 0xF0,
        NULL, HFILL }
    },
    { &hf_ansi_801_rev_message_number_responses0F,
      { "Number Responses", "ansi_801.rev_message_number_responses",
        FT_UINT8, BASE_DEC, NULL, 0x0F,
        NULL, HFILL }
    },
    { &hf_ansi_801_data,
      { "Data", "ansi_801.data",
        FT_BYTES, BASE_NONE, NULL, 0x0,
        NULL, HFILL }
    },
    { &hf_ansi_801_proprietary_data,
      { "Reserved/Proprietary/Future Data", "ansi_801.proprietary_data",
        FT_BYTES, BASE_NONE, NULL, 0x0,
        NULL, HFILL }
    },
    { &hf_ansi_801_time_ref_ms,
      { "TIME_REF_MS", "ansi_801.time_ref_ms",
        FT_UINT24, BASE_DEC, NULL, 0x0,
        NULL, HFILL }
    },
    { &hf_ansi_801_time_of_almanac,
      { "Time of almanac", "ansi_801.time_of_almanac",
        FT_UINT8, BASE_DEC|BASE_UNIT_STRING, UNS(&units_time_of_almanac), 0x0,
        NULL, HFILL }
    },
    { &hf_ansi_801_gps_week_number,
      { "GPS week number", "ansi_801.gps_week_number",
        FT_UINT8, BASE_DEC|BASE_UNIT_STRING, UNS(&units_gps_week_number), 0x0,
        NULL, HFILL }
    },
  };

  /* Setup protocol subtree array */
#define NUM_INDIVIDUAL_PARAMS 3
  int *ett[NUM_INDIVIDUAL_PARAMS+NUM_FOR_REQ_TYPE+NUM_FOR_RSP_TYPE+NUM_REV_REQ_TYPE+NUM_REV_RSP_TYPE];


  static ei_register_info ei[] = {
    { &ei_ansi_801_extraneous_data, { "ansi_801.extraneous_data", PI_PROTOCOL, PI_NOTE, "Extraneous Data, dissector bug or later version spec (report to wireshark.org)", EXPFILL }},
    { &ei_ansi_801_short_data, { "ansi_801.short_data", PI_PROTOCOL, PI_NOTE, "Short Data (?) - try checking decoder variant preference or dissector bug/later version spec (report to wireshark.org)", EXPFILL }},
    { &ei_ansi_801_unexpected_length, { "ansi_801.unexpected_length", PI_PROTOCOL, PI_WARN, "Unexpected Data Length - try checking decoder variant preference or dissector bug/later version spec (report to wireshark.org)", EXPFILL }},
  };

  expert_module_t* expert_ansi_801;

  ett[0] = &ett_ansi_801;
  ett[1] = &ett_gps;
  ett[2] = &ett_loc;

  last_offset = NUM_INDIVIDUAL_PARAMS;

  for (i=0; i < NUM_FOR_REQ_TYPE; i++, last_offset++)
  {
    ett[last_offset] = &ett_for_req_type[i];
  }

  for (i=0; i < NUM_FOR_RSP_TYPE; i++, last_offset++)
  {
    ett[last_offset] = &ett_for_rsp_type[i];
  }

  for (i=0; i < NUM_REV_REQ_TYPE; i++, last_offset++)
  {
    ett[last_offset] = &ett_rev_req_type[i];
  }

  for (i=0; i < NUM_REV_RSP_TYPE; i++, last_offset++)
  {
    ett[last_offset] = &ett_rev_rsp_type[i];
  }

  /* Register the protocol name and description */
  proto_ansi_801 =
    proto_register_protocol(ansi_proto_name, "ANSI IS-801 (Location Services (PLD))", "ansi_801");

  /* Required function calls to register the header fields and subtrees used */
  proto_register_field_array(proto_ansi_801, hf, array_length(hf));
  proto_register_subtree_array(ett, array_length(ett));
  expert_ansi_801 = expert_register_protocol(proto_ansi_801);
  expert_register_field_array(expert_ansi_801, ei, array_length(ei));

  /* subdissector code */
  ansi_801_handle = register_dissector("ansi_801", dissect_ansi_801, proto_ansi_801);
}


void
proto_reg_handoff_ansi_801(void)
{
  dissector_add_uint("ansi_map.pld", ANSI_801_FORWARD, ansi_801_handle);
  dissector_add_uint("ansi_map.pld", ANSI_801_REVERSE, ansi_801_handle);
  dissector_add_uint("ansi_a.pld",   ANSI_801_FORWARD, ansi_801_handle);
  dissector_add_uint("ansi_a.pld",   ANSI_801_REVERSE, ansi_801_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:
 */

Coverage Report

Created: 2025-08-04 07:15