add GAD coding for Location Services
GAD, Universal Geographical Area Description:
- raw coding for all GAD elements.
- SI-units encoding and decoding for Ellipsoid point with uncertainty circle,
which I presume is the typical "at most N meters away from cell tower located
at X,Y", which corresponds to the TA positioning currently being implemented.
- other SI-units GAD element encodings are so far not implemented.
Add encoding and decoding tests.
In gsm/protocol/gsm_23_032.h are the raw coding structs as defined in 3GPP TS
23.032.
In gsm/gad.h are structs carrying consistent units based on meters and degrees,
for convenient / less error prone handling of GAD data, and for human readable
representations of the GAD data.
The separation of the two is desirable because OsmoBSC will receive GAD data
from OsmoSMLC on the Lb interface, and pass on this data to the MSC via the A
interface. It is better to pass the GAD data as-is without de/encoding.
Change-Id: I7a9dd805a91b1ebb6353bde0cd169218acbf223c
diff --git a/include/osmocom/gsm/protocol/gsm_23_032.h b/include/osmocom/gsm/protocol/gsm_23_032.h
new file mode 100644
index 0000000..5be98a2
--- /dev/null
+++ b/include/osmocom/gsm/protocol/gsm_23_032.h
@@ -0,0 +1,172 @@
+/*! \defgroup gad 3GPP TS 23.032 GAD: Universal Geographical Area Description.
+ * @{
+ * \file gsm_23_032.h
+ */
+/*
+ * (C) 2020 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ *
+ * All Rights Reserved
+ *
+ * Author: Neels Hofmeyr <neels@hofmeyr.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#pragma once
+
+#include <stdint.h>
+#include <osmocom/core/endian.h>
+
+enum gad_type {
+ /*! Ellipsoid point */
+ GAD_TYPE_ELL_POINT = 0,
+ /*! Ellipsoid point with uncertainty circle. */
+ GAD_TYPE_ELL_POINT_UNC_CIRCLE = 1,
+ /*! Ellipsoid point with uncertainty ellipse. */
+ GAD_TYPE_ELL_POINT_UNC_ELLIPSE = 3,
+ GAD_TYPE_POLYGON = 5,
+ /*! Ellipsoid point with altitude. */
+ GAD_TYPE_ELL_POINT_ALT = 8,
+ /*! Ellipsoid point with altitude and uncertainty ellipsoid. */
+ GAD_TYPE_ELL_POINT_ALT_UNC_ELL = 9,
+ /*! Ellipsoid arc */
+ GAD_TYPE_ELL_ARC = 10,
+ /*! High accuracy ellipsoid point with uncertainty ellipse. */
+ GAD_TYPE_HA_ELL_POINT_UNC_ELLIPSE = 11,
+ /*! High accuracy ellipsoid point with altitude and uncertainty ellipsoid. */
+ GAD_TYPE_HA_ELL_POINT_ALT_UNC_ELL = 12,
+};
+
+struct gad_raw_head {
+ uint8_t spare:4,
+ type:4;
+} __attribute__ ((packed));
+
+struct gad_raw_ell_point {
+ struct gad_raw_head h; /*!< type = GAD_TYPE_ELL_POINT */
+ uint8_t lat[3];
+ uint8_t lon[3];
+} __attribute__ ((packed));
+
+struct gad_raw_ell_point_unc_circle {
+ struct gad_raw_head h; /*!< type = GAD_TYPE_ELL_POINT_UNC_CIRCLE */
+ uint8_t lat[3];
+ uint8_t lon[3];
+ uint8_t unc:7,
+ spare2:1;
+} __attribute__ ((packed));
+
+struct gad_raw_ell_point_unc_ellipse {
+ struct gad_raw_head h; /*!< type = GAD_TYPE_ELL_POINT_UNC_ELLIPSE */
+ uint8_t lat[3];
+ uint8_t lon[3];
+ uint8_t unc_semi_major:7,
+ spare1:1;
+ uint8_t unc_semi_minor:7,
+ spare2:1;
+ uint8_t major_ori;
+ uint8_t confidence:7,
+ spare3:1;
+} __attribute__ ((packed));
+
+struct gad_raw_polygon {
+ struct {
+ uint8_t num_points:4;
+ uint8_t type:4; /*!< type = GAD_TYPE_POLYGON */
+ } h;
+ struct {
+ uint8_t lat[3];
+ uint8_t lon[3];
+ } point[15];
+} __attribute__ ((packed));
+
+struct gad_raw_ell_point_alt {
+ struct gad_raw_head h; /*!< type = GAD_TYPE_ELL_POINT_ALT */
+ uint8_t lat[3];
+ uint8_t lon[3];
+ uint8_t alt[2];
+} __attribute__ ((packed));
+
+struct gad_raw_ell_point_alt_unc_ell {
+ struct gad_raw_head h; /*!< type = GAD_TYPE_ELL_POINT_ALT_UNC_ELL */
+ uint8_t lat[3];
+ uint8_t lon[3];
+ uint8_t alt[2];
+ uint8_t unc_semi_major:7,
+ spare1:1;
+ uint8_t unc_semi_minor:7,
+ spare2:1;
+ uint8_t major_ori;
+ uint8_t unc_alt:7,
+ spare3:1;
+ uint8_t confidence:7,
+ spare4:1;
+} __attribute__ ((packed));
+
+struct gad_raw_ell_arc {
+ struct gad_raw_head h; /*!< type = GAD_TYPE_ELL_ARC */
+ uint8_t lat[3];
+ uint8_t lon[3];
+ uint8_t inner_r[2];
+ uint8_t unc_r:7,
+ spare1:1;
+ uint8_t ofs_angle;
+ uint8_t incl_angle;
+ uint8_t confidence:7,
+ spare2:1;
+} __attribute__ ((packed));
+
+struct gad_raw_ha_ell_point_unc_ell {
+ struct gad_raw_head h; /*!< type = GAD_TYPE_HA_ELL_POINT_UNC_ELLIPSE */
+ uint8_t lat[4];
+ uint8_t lon[4];
+ uint8_t alt[3];
+ uint8_t unc_semi_major;
+ uint8_t unc_semi_minor;
+ uint8_t major_ori;
+ uint8_t confidence:7,
+ spare1:1;
+} __attribute__ ((packed));
+
+struct gad_raw_ha_ell_point_alt_unc_ell {
+ struct gad_raw_head h; /*!< type = GAD_TYPE_HA_ELL_POINT_ALT_UNC_ELL */
+ uint8_t lat[4];
+ uint8_t lon[4];
+ uint8_t alt[3];
+ uint8_t unc_semi_major;
+ uint8_t unc_semi_minor;
+ uint8_t major_ori;
+ uint8_t h_confidence:7,
+ spare1:1;
+ uint8_t unc_alt;
+ uint8_t v_confidence:7,
+ spare2:1;
+} __attribute__ ((packed));
+
+/*! GAD PDU in network-byte-order according to 3GPP TS 23.032 GAD: Universal Geographical Area Description. */
+union gad_raw {
+ struct gad_raw_head h;
+ struct gad_raw_ell_point ell_point;
+ struct gad_raw_ell_point_unc_circle ell_point_unc_circle;
+ struct gad_raw_ell_point_unc_ellipse ell_point_unc_ellipse;
+ struct gad_raw_polygon polygon;
+ struct gad_raw_ell_point_alt ell_point_alt;
+ struct gad_raw_ell_point_alt_unc_ell ell_point_alt_unc_ell;
+ struct gad_raw_ell_arc ell_arc;
+ struct gad_raw_ha_ell_point_unc_ell ha_ell_point_unc_ell;
+ struct gad_raw_ha_ell_point_alt_unc_ell ha_ell_point_alt_unc_ell;
+} __attribute__ ((packed));
+
+/*! @} */