From 5b214e2847cb8264e42494e7474f3e3d350aaab7 Mon Sep 17 00:00:00 2001 From: Neels Hofmeyr Date: Fri, 18 Sep 2020 18:00:50 +0200 Subject: add BSSMAP coding for Location Services BSSMAP: add A-interface messages between MSC and BSC: - Perform Location Request - Perform Location Response - Perform Location Abort Change-Id: I4d7302a4853518916b6b425e710c10568eb2ffe5 --- include/Makefile.am | 1 + include/osmocom/gsm/gsm0808_lcs.h | 52 +++++++++++++++++++ src/gsm/gsm0808.c | 102 ++++++++++++++++++++++++++++++++++++++ src/gsm/libosmogsm.map | 3 ++ 4 files changed, 158 insertions(+) create mode 100644 include/osmocom/gsm/gsm0808_lcs.h diff --git a/include/Makefile.am b/include/Makefile.am index 90f448aa..44ff3789 100644 --- a/include/Makefile.am +++ b/include/Makefile.am @@ -96,6 +96,7 @@ nobase_include_HEADERS = \ osmocom/gsm/bssmap_le.h \ osmocom/gsm/gad.h \ osmocom/gsm/gsm0808.h \ + osmocom/gsm/gsm0808_lcs.h \ osmocom/gsm/gsm29205.h \ osmocom/gsm/gsm0808_utils.h \ osmocom/gsm/gsm23003.h \ diff --git a/include/osmocom/gsm/gsm0808_lcs.h b/include/osmocom/gsm/gsm0808_lcs.h new file mode 100644 index 00000000..8fcbe380 --- /dev/null +++ b/include/osmocom/gsm/gsm0808_lcs.h @@ -0,0 +1,52 @@ +/*! \addtogroup gsm0808 + * @{ + * \file gsm0808_lcs.h + * + * Declarations that depend on both gsm0808.h and bssmap_le.h: LCS related message coding. + * (This file prevents circular dependency between struct definitions for BSSMAP messages, since BSSMAP references + * struct lcs_cause and struct bssmap_le_location_type, and BSSMAP-LE references gsm0808_cause. + */ +/* + * (C) 2020 by sysmocom - s.f.m.c. GmbH + * All Rights Reserved + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + * + */ +#pragma once + +#include +#include + +struct gsm0808_perform_location_request { + struct bssmap_le_location_type location_type; + struct osmo_mobile_identity imsi; + + bool more_items; /*!< always set this to false */ +}; +struct msgb *gsm0808_create_perform_location_request(const struct gsm0808_perform_location_request *params); + +struct gsm0808_perform_location_response { + bool location_estimate_present; + union gad_raw location_estimate; + + struct lcs_cause_ie lcs_cause; +}; +struct msgb *gsm0808_create_perform_location_response(const struct gsm0808_perform_location_response *params); + +int gsm0808_enc_lcs_cause(struct msgb *msg, const struct lcs_cause_ie *lcs_cause); +struct msgb *gsm0808_create_perform_location_abort(const struct lcs_cause_ie *lcs_cause); + +/*! @} */ diff --git a/src/gsm/gsm0808.c b/src/gsm/gsm0808.c index 53220617..971d9625 100644 --- a/src/gsm/gsm0808.c +++ b/src/gsm/gsm0808.c @@ -26,9 +26,11 @@ #include #include #include +#include #include #include #include +#include /*! \addtogroup gsm0808 * @{ @@ -1341,6 +1343,106 @@ struct msgb *gsm0808_create_dtap(struct msgb *msg_l3, uint8_t link_id) return msg; } +struct msgb *gsm0808_create_perform_location_request(const struct gsm0808_perform_location_request *params) +{ + struct msgb *msg; + uint8_t *out; + int rc; + + msg = msgb_alloc_headroom(BSSMAP_MSG_SIZE, BSSMAP_MSG_HEADROOM, "BSSMAP-PERFORM-LOCATION-REQUEST"); + if (!msg) + return NULL; + + /* Message Type, 3.2.2.1 */ + msgb_v_put(msg, BSS_MAP_MSG_PERFORM_LOCATION_RQST); + + /* Location Type 3.2.2.63 */ + osmo_bssmap_le_ie_enc_location_type(msg, ¶ms->location_type); + + if (params->imsi.type == GSM_MI_TYPE_IMSI) { + /* IMSI 3.2.2.6 */ + out = msgb_tl_put(msg, GSM0808_IE_IMSI); + rc = osmo_mobile_identity_encode_msgb(msg, ¶ms->imsi, false); + if (rc < 0) { + msgb_free(msg); + return NULL; + } + /* write the MI value length */ + *out = rc; + } + + /* prepend header with final length */ + msg->l3h = msgb_tv_push(msg, BSSAP_MSG_BSS_MANAGEMENT, msgb_length(msg)); + + return msg; +} + +struct msgb *gsm0808_create_perform_location_response(const struct gsm0808_perform_location_response *params) +{ + struct msgb *msg; + + msg = msgb_alloc_headroom(BSSMAP_MSG_SIZE, BSSMAP_MSG_HEADROOM, "BSSMAP-PERFORM-LOCATION-RESPONSE"); + if (!msg) + return NULL; + + /* Message Type, 3.2.2.1 */ + msgb_v_put(msg, BSS_MAP_MSG_PERFORM_LOCATION_RESPONSE); + + if (params->location_estimate_present) { + uint8_t *l = msgb_tl_put(msg, GSM0808_IE_LOCATION_ESTIMATE); + int rc = osmo_gad_raw_write(msg, ¶ms->location_estimate); + if (rc < 0) { + msgb_free(msg); + return NULL; + } + *l = rc; + } + + if (params->lcs_cause.present) { + uint8_t *l = msgb_tl_put(msg, GSM0808_IE_LCS_CAUSE); + int rc = osmo_lcs_cause_enc(msg, ¶ms->lcs_cause); + if (rc < 0) { + msgb_free(msg); + return NULL; + } + *l = rc; + } + + /* prepend header with final length */ + msg->l3h = msgb_tv_push(msg, BSSAP_MSG_BSS_MANAGEMENT, msgb_length(msg)); + + return msg; +} + +int gsm0808_enc_lcs_cause(struct msgb *msg, const struct lcs_cause_ie *lcs_cause) +{ + uint8_t *l = msgb_tl_put(msg, GSM0808_IE_LCS_CAUSE); + int rc = osmo_lcs_cause_enc(msg, lcs_cause); + if (rc <= 0) + return rc; + *l = rc; + return rc + 2; +} + +struct msgb *gsm0808_create_perform_location_abort(const struct lcs_cause_ie *lcs_cause) +{ + struct msgb *msg; + + msg = msgb_alloc_headroom(BSSMAP_MSG_SIZE, BSSMAP_MSG_HEADROOM, "BSSMAP-PERFORM-LOCATION-ABORT"); + if (!msg) + return NULL; + + /* Message Type, 3.2.2.1 */ + msgb_v_put(msg, BSS_MAP_MSG_PERFORM_LOCATION_ABORT); + + gsm0808_enc_lcs_cause(msg, lcs_cause); + + /* prepend header with final length */ + msg->l3h = msgb_tv_push(msg, BSSAP_MSG_BSS_MANAGEMENT, msgb_length(msg)); + + return msg; +} + /* As per 3GPP TS 48.008 version 11.7.0 Release 11 */ static const struct tlv_definition bss_att_tlvdef = { .def = { diff --git a/src/gsm/libosmogsm.map b/src/gsm/libosmogsm.map index 89d81b34..1fd212d5 100644 --- a/src/gsm/libosmogsm.map +++ b/src/gsm/libosmogsm.map @@ -255,6 +255,9 @@ gsm0808_enc_lcls; gsm0808_dec_lcls; gsm0808_msgb_put_cell_id_u; gsm0808_decode_cell_id_u; +gsm0808_create_perform_location_request; +gsm0808_create_perform_location_response; +gsm0808_create_perform_location_abort; gsm29118_msgb_alloc; gsm29118_create_alert_req; -- cgit v1.2.3