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/* packet-ubx-galileo_e1b_inav.c
* Dissection of Galileo E1-B I/NAV navigation messages
* (as provided by UBX-RXM-SFRBX).
*
* By Timo Warns <timo.warns@gmail.com>
* Copyright 2023 Timo Warns
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@unicom.net>
* Copyright 1998 Gerald Combs
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "config.h"
#include <epan/packet.h>
#include <wsutil/pint.h>
#include <wsutil/utf8_entities.h>
#include "packet-ubx.h"
/*
* Dissects Galileo E1-B I/NAV navigation messages
* as encoded by UBX (in UBX-RXM-SFRBX messages).
* Based on Galileo OS SIS ICD Issue 2.1
*/
// Initialize the protocol and registered fields
static int proto_ubx_gal_inav;
static int hf_ubx_gal_inav_even_odd;
static int hf_ubx_gal_inav_page_type;
static int hf_ubx_gal_inav_type;
static int hf_ubx_gal_inav_data_122_67;
static int hf_ubx_gal_inav_data_66_17;
static int hf_ubx_gal_inav_data_16_1;
static int hf_ubx_gal_inav_osnma;
static int hf_ubx_gal_inav_sar_start_bit;
static int hf_ubx_gal_inav_sar_long_rlm;
static int hf_ubx_gal_inav_sar_beacon_1;
static int hf_ubx_gal_inav_sar_rlm_data;
static int hf_ubx_gal_inav_spare;
static int hf_ubx_gal_inav_ssp;
static int hf_ubx_gal_inav_crc;
static int hf_ubx_gal_inav_tail;
static int hf_ubx_gal_inav_pad;
static int hf_ubx_gal_inav_reserved_1;
static int hf_ubx_gal_inav_word0;
static int hf_ubx_gal_inav_word0_type;
static int hf_ubx_gal_inav_word0_time;
static int hf_ubx_gal_inav_word0_spare;
static int hf_ubx_gal_inav_word0_wn;
static int hf_ubx_gal_inav_word0_tow;
static int hf_ubx_gal_inav_word1;
static int hf_ubx_gal_inav_word1_type;
static int hf_ubx_gal_inav_word1_iodnav;
static int hf_ubx_gal_inav_word1_t0e;
static int hf_ubx_gal_inav_word1_m0;
static int hf_ubx_gal_inav_word1_e;
static int hf_ubx_gal_inav_word1_sqrta;
static int hf_ubx_gal_inav_word1_reserved;
static dissector_table_t ubx_gal_inav_word_dissector_table;
static int ett_ubx_gal_inav;
static int ett_ubx_gal_inav_word0;
static int ett_ubx_gal_inav_word1;
static int ett_ubx_gal_inav_sar;
static const value_string GAL_PAGE_TYPE[] = {
{0, "nominal"},
{1, "alert"},
{0, NULL},
};
static const value_string GAL_SSP[] = {
{0x04, "SSP 1"},
{0x2b, "SSP 2"},
{0x2f, "SSP 3"},
{0, NULL},
};
/* Format mean anomaly at reference time */
static void fmt_m0(char *label, int64_t c) {
snprintf(label, ITEM_LABEL_LENGTH, "%" PRId64 " * 2^-31 semi-circles", c);
}
/* Format eccentricity */
static void fmt_e(char *label, uint64_t c) {
snprintf(label, ITEM_LABEL_LENGTH, "%" PRIu64 " * 2^-33", c);
}
/* Format square root of the semi-major axis */
static void fmt_sqrt_a(char *label, uint64_t c) {
snprintf(label, ITEM_LABEL_LENGTH, "%" PRIu64 " * 2^-19 " UTF8_SQUARE_ROOT "m", c);
}
/* Format ephemeris reference time */
static void fmt_t0e(char *label, uint32_t c) {
c = c * 60;
snprintf(label, ITEM_LABEL_LENGTH, "%ds", c);
}
/* Dissect Galileo E1-B I/NAV navigation message */
static int dissect_ubx_gal_inav(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_) {
tvbuff_t *next_tvb;
bool sar_start, sar_long_rlm;
uint32_t inav_type, page_type;
uint64_t data_122_67, data_66_17, data_16_1;
uint8_t *word;
col_set_str(pinfo->cinfo, COL_PROTOCOL, "Galileo E1-B I/NAV");
col_clear(pinfo->cinfo, COL_INFO);
proto_tree *gal_inav_tree = proto_tree_add_subtree(tree, tvb, 0, 32, ett_ubx_gal_inav, NULL, "Galileo E1-B I/NAV");
// even page
proto_tree_add_item(gal_inav_tree, hf_ubx_gal_inav_even_odd, tvb, 0, 1, ENC_NA);
proto_tree_add_item_ret_uint(gal_inav_tree, hf_ubx_gal_inav_page_type, tvb, 0, 1, ENC_NA, &page_type);
if (page_type == 1) { // alert page
proto_tree_add_item(gal_inav_tree, hf_ubx_gal_inav_reserved_1, tvb, 0, 15, ENC_NA);
}
else { // nominal page
proto_tree_add_item_ret_uint(gal_inav_tree, hf_ubx_gal_inav_type, tvb, 0, 1, ENC_NA, &inav_type);
proto_tree_add_item_ret_uint64(gal_inav_tree, hf_ubx_gal_inav_data_122_67, tvb, 0, 8, ENC_BIG_ENDIAN, &data_122_67);
proto_tree_add_item_ret_uint64(gal_inav_tree, hf_ubx_gal_inav_data_66_17, tvb, 8, 8, ENC_BIG_ENDIAN, &data_66_17);
}
proto_tree_add_item(gal_inav_tree, hf_ubx_gal_inav_tail, tvb, 14, 1, ENC_NA);
proto_tree_add_item(gal_inav_tree, hf_ubx_gal_inav_pad, tvb, 15, 1, ENC_NA);
// odd page
proto_tree_add_item(gal_inav_tree, hf_ubx_gal_inav_even_odd, tvb, 16, 1, ENC_NA);
proto_tree_add_item_ret_uint(gal_inav_tree, hf_ubx_gal_inav_page_type, tvb, 16, 1, ENC_NA, &page_type);
if (page_type == 1) { // alert page
proto_tree_add_item(gal_inav_tree, hf_ubx_gal_inav_reserved_1, tvb, 16, 11, ENC_NA);
}
else { // nominal page
proto_tree_add_item_ret_uint64(gal_inav_tree, hf_ubx_gal_inav_data_16_1, tvb, 16, 8, ENC_BIG_ENDIAN, &data_16_1);
proto_tree_add_item(gal_inav_tree, hf_ubx_gal_inav_osnma, tvb, 16, 8, ENC_BIG_ENDIAN);
proto_tree *sar_tree = proto_tree_add_subtree(gal_inav_tree, tvb, 23, 4, ett_ubx_gal_inav_sar, NULL, "SAR");
proto_tree_add_item_ret_boolean(sar_tree, hf_ubx_gal_inav_sar_start_bit, tvb, 23, 4, ENC_BIG_ENDIAN, &sar_start);
proto_tree_add_item_ret_boolean(sar_tree, hf_ubx_gal_inav_sar_long_rlm, tvb, 23, 4, ENC_BIG_ENDIAN, &sar_long_rlm);
if (sar_start) {
proto_tree_add_item(sar_tree, hf_ubx_gal_inav_sar_beacon_1, tvb, 23, 4, ENC_BIG_ENDIAN);
}
else {
// TODO: add more elaborate dissection for subsequent RLM data (requiring state tracking)
proto_tree_add_item(sar_tree, hf_ubx_gal_inav_sar_rlm_data, tvb, 23, 4, ENC_BIG_ENDIAN);
}
proto_tree_add_item(gal_inav_tree, hf_ubx_gal_inav_spare, tvb, 26, 1, ENC_NA);
}
// TODO: check CRC
proto_tree_add_item(gal_inav_tree, hf_ubx_gal_inav_crc, tvb, 26, 4, ENC_BIG_ENDIAN);
proto_tree_add_item(gal_inav_tree, hf_ubx_gal_inav_ssp, tvb, 28, 4, ENC_BIG_ENDIAN);
proto_tree_add_item(gal_inav_tree, hf_ubx_gal_inav_tail, tvb, 30, 1, ENC_NA);
proto_tree_add_item(gal_inav_tree, hf_ubx_gal_inav_pad, tvb, 31, 1, ENC_NA);
// handoff the data word of a nominal page
if (page_type == 0) {
// create new tvb with the data word
word = wmem_alloc(pinfo->pool, 16);
phton16(word + 14, data_16_1);
phton64(word + 6, data_66_17);
phton64(word, (((uint64_t) inav_type) << 58) | (data_122_67 << 2) | (data_66_17 >> 48));
next_tvb = tvb_new_child_real_data(tvb, (uint8_t *)word, 16, 16);
add_new_data_source(pinfo, next_tvb, "Galileo I/NAV Word");
// handoff to appropriate dissector
if (!dissector_try_uint(ubx_gal_inav_word_dissector_table, inav_type, next_tvb, pinfo, tree)) {
call_data_dissector(next_tvb, pinfo, tree);
}
}
return tvb_captured_length(tvb);
}
/* Dissect word 0 - I/NAV Spare Word */
static int dissect_ubx_gal_inav_word0(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree, void *data _U_) {
col_append_str(pinfo->cinfo, COL_INFO, "Word 0 (Spare Word)");
proto_item *ti = proto_tree_add_item(tree, hf_ubx_gal_inav_word0, tvb, 0, 16, ENC_NA);
proto_tree *word_tree = proto_item_add_subtree(ti, ett_ubx_gal_inav_word0);
proto_tree_add_item(word_tree, hf_ubx_gal_inav_word0_type, tvb, 0, 1, ENC_NA);
proto_tree_add_item(word_tree, hf_ubx_gal_inav_word0_time, tvb, 0, 1, ENC_NA);
proto_tree_add_item(word_tree, hf_ubx_gal_inav_word0_spare, tvb, 1, 11, ENC_NA);
proto_tree_add_item(word_tree, hf_ubx_gal_inav_word0_wn, tvb, 12, 4, ENC_BIG_ENDIAN);
proto_tree_add_item(word_tree, hf_ubx_gal_inav_word0_tow, tvb, 12, 4, ENC_BIG_ENDIAN);
return tvb_captured_length(tvb);
}
/* Dissect word 1 - Ephemeris (1/4) */
static int dissect_ubx_gal_inav_word1(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree, void *data _U_) {
col_append_str(pinfo->cinfo, COL_INFO, "Word 1 (Ephemeris (1/4))");
proto_item *ti = proto_tree_add_item(tree, hf_ubx_gal_inav_word1, tvb, 0, 16, ENC_NA);
proto_tree *word_tree = proto_item_add_subtree(ti, ett_ubx_gal_inav_word1);
proto_tree_add_item(word_tree, hf_ubx_gal_inav_word1_type, tvb, 0, 1, ENC_NA);
proto_tree_add_item(word_tree, hf_ubx_gal_inav_word1_iodnav, tvb, 0, 2, ENC_BIG_ENDIAN);
proto_tree_add_item(word_tree, hf_ubx_gal_inav_word1_t0e, tvb, 2, 2, ENC_BIG_ENDIAN);
proto_tree_add_item(word_tree, hf_ubx_gal_inav_word1_m0, tvb, 3, 8, ENC_BIG_ENDIAN);
proto_tree_add_item(word_tree, hf_ubx_gal_inav_word1_e, tvb, 7, 8, ENC_BIG_ENDIAN);
proto_tree_add_item(word_tree, hf_ubx_gal_inav_word1_sqrta, tvb, 8, 8, ENC_BIG_ENDIAN);
proto_tree_add_item(word_tree, hf_ubx_gal_inav_word1_reserved, tvb, 15, 1, ENC_NA);
return tvb_captured_length(tvb);
}
void proto_register_ubx_gal_inav(void) {
static hf_register_info hf[] = {
{&hf_ubx_gal_inav_even_odd, {"Even/Odd", "gal_inav.even_odd", FT_BOOLEAN, 8, TFS(&tfs_odd_even), 0x80, NULL, HFILL}},
{&hf_ubx_gal_inav_page_type, {"Page Type", "gal_inav.page_type", FT_UINT8, BASE_DEC, VALS(GAL_PAGE_TYPE), 0x40, NULL, HFILL}},
{&hf_ubx_gal_inav_type, {"Type", "gal_inav.type", FT_UINT8, BASE_DEC, NULL, 0x3f, NULL, HFILL}},
{&hf_ubx_gal_inav_data_122_67, {"Data (122-67)", "gal_inav.data_122_67", FT_UINT64, BASE_HEX, NULL, 0x00ffffffffffffff, NULL, HFILL}},
{&hf_ubx_gal_inav_data_66_17, {"Data (66-17)", "gal_inav.data_66_17", FT_UINT64, BASE_HEX, NULL, 0xffffffffffffc000, NULL, HFILL}},
{&hf_ubx_gal_inav_data_16_1, {"Data (16-1)", "gal_inav.data_16_1", FT_UINT64, BASE_HEX, NULL, 0x3fffc00000000000, NULL, HFILL}},
{&hf_ubx_gal_inav_osnma, {"OSNMA", "gal_inav.osnma", FT_UINT64, BASE_HEX, NULL, 0x00003fffffffffc0, NULL, HFILL}},
{&hf_ubx_gal_inav_sar_start_bit, {"Start bit", "gal_inav.sar.start_bit", FT_BOOLEAN, 32, NULL, 0x20000000, NULL, HFILL}},
{&hf_ubx_gal_inav_sar_long_rlm, {"Long RLM", "gal_inav.sar.long_rlm", FT_BOOLEAN, 32, NULL, 0x10000000, NULL, HFILL}},
{&hf_ubx_gal_inav_sar_beacon_1, {"Beacon (1/3)", "gal_inav.sar.beacon_1", FT_UINT32, BASE_HEX, NULL, 0x0fffff00, NULL, HFILL}},
{&hf_ubx_gal_inav_sar_rlm_data, {"RLM data", "gal_inav.sar.rlm_data", FT_UINT32, BASE_HEX, NULL, 0x0fffff00, NULL, HFILL}},
{&hf_ubx_gal_inav_spare, {"Spare", "gal_inav.spare", FT_UINT8, BASE_HEX, NULL, 0xc0, NULL, HFILL}},
{&hf_ubx_gal_inav_reserved_1, {"Reserved 1", "gal_inav.reserved_1", FT_NONE, BASE_NONE, NULL, 0x0, NULL, HFILL}},
{&hf_ubx_gal_inav_crc, {"CRC", "gal_inav.crc", FT_UINT32, BASE_HEX, NULL, 0x3fffffc0, NULL, HFILL}},
{&hf_ubx_gal_inav_ssp, {"SSP", "gal_inav.ssp", FT_UINT32, BASE_HEX, VALS(GAL_SSP), 0x003fc000, NULL, HFILL}},
{&hf_ubx_gal_inav_tail, {"Tail", "gal_inav.tail", FT_UINT8, BASE_HEX, NULL, 0x3f, NULL, HFILL}},
{&hf_ubx_gal_inav_pad, {"Pad", "gal_inav.pad", FT_UINT8, BASE_HEX, NULL, 0x0, NULL, HFILL}},
// Word 0
{&hf_ubx_gal_inav_word0, {"Word 0 (Spare Word)", "gal_inav.word0", FT_NONE, BASE_NONE, NULL, 0x0, NULL, HFILL}},
{&hf_ubx_gal_inav_word0_type, {"Type", "gal_inav.word0.type", FT_UINT8, BASE_HEX, NULL, 0xfc, NULL, HFILL}},
{&hf_ubx_gal_inav_word0_time, {"Time", "gal_inav.word0.time", FT_UINT8, BASE_HEX, NULL, 0x03, NULL, HFILL}},
{&hf_ubx_gal_inav_word0_spare, {"Spare", "gal_inav.word0.spare", FT_BYTES, BASE_NONE|SEP_SPACE, NULL, 0x0, NULL, HFILL}},
{&hf_ubx_gal_inav_word0_wn, {"Week Number", "gal_inav.word0.wn", FT_UINT32, BASE_DEC, NULL, 0xfff00000, NULL, HFILL}},
{&hf_ubx_gal_inav_word0_tow, {"Time of Week", "gal_inav.word0.tow", FT_UINT32, BASE_DEC, NULL, 0x000fffff, NULL, HFILL}},
// Word 1
{&hf_ubx_gal_inav_word1, {"Word 1 (Ephemeris (1/4))", "gal_inav.word1", FT_NONE, BASE_NONE, NULL, 0x0, NULL, HFILL}},
{&hf_ubx_gal_inav_word1_type, {"Type", "gal_inav.word1.type", FT_UINT8, BASE_HEX, NULL, 0xfc, NULL, HFILL}},
{&hf_ubx_gal_inav_word1_iodnav, {"IOD_nav", "gal_inav.word1.iod_nav", FT_UINT16, BASE_DEC, NULL, 0x03ff, NULL, HFILL}},
{&hf_ubx_gal_inav_word1_t0e, {"Ephemeris reference time (t_0e)", "gal_inav.word1.t_0e", FT_UINT16, BASE_CUSTOM, CF_FUNC(&fmt_t0e), 0xfffc, NULL, HFILL}},
{&hf_ubx_gal_inav_word1_m0, {"Mean anomaly at reference time (M_0)", "gal_inav.word1.m_0", FT_INT64, BASE_CUSTOM, CF_FUNC(&fmt_m0), 0x03fffffffc000000, NULL, HFILL}},
{&hf_ubx_gal_inav_word1_e, {"Eccentricity (e)", "gal_inav.word1.e", FT_UINT64, BASE_CUSTOM, CF_FUNC(&fmt_e), 0x03fffffffc000000, NULL, HFILL}},
{&hf_ubx_gal_inav_word1_sqrta, {"Square root of the semi-major axis (" UTF8_SQUARE_ROOT "a)", "gal_inav.word1.sqrt_a", FT_UINT64, BASE_CUSTOM, CF_FUNC(&fmt_sqrt_a), 0x00000003fffffffc, NULL, HFILL}},
{&hf_ubx_gal_inav_word1_reserved,{"Reserved", "gal_inav.word1.reserved", FT_UINT8, BASE_HEX, NULL, 0x03, NULL, HFILL}},
};
static int *ett[] = {
&ett_ubx_gal_inav,
&ett_ubx_gal_inav_sar,
};
proto_ubx_gal_inav = proto_register_protocol("Galileo E1-B I/NAV Navigation Message", "Galileo I/NAV", "gal_inav");
proto_register_field_array(proto_ubx_gal_inav, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
register_dissector("ubx_gal_inav", dissect_ubx_gal_inav, proto_ubx_gal_inav);
ubx_gal_inav_word_dissector_table = register_dissector_table("ubx.rxm.sfrbx.gal_inav.word",
"Galileo I/NAV Word", proto_ubx_gal_inav, FT_UINT8, BASE_DEC);
}
void proto_reg_handoff_ubx_gal_inav(void) {
dissector_add_uint("ubx.rxm.sfrbx.gnssid", GNSS_ID_GALILEO, create_dissector_handle(dissect_ubx_gal_inav, proto_ubx_gal_inav));
dissector_add_uint("ubx.rxm.sfrbx.gal_inav.word", 0, create_dissector_handle(dissect_ubx_gal_inav_word0, proto_ubx_gal_inav));
dissector_add_uint("ubx.rxm.sfrbx.gal_inav.word", 1, create_dissector_handle(dissect_ubx_gal_inav_word1, proto_ubx_gal_inav));
}
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