| /* MSC Handover API */ |
| /* |
| * (C) 2019 by sysmocom - s.m.f.c. GmbH <info@sysmocom.de> |
| * All Rights Reserved |
| * |
| * SPDX-License-Identifier: AGPL-3.0+ |
| * |
| * Author: Neels Hofmeyr |
| * |
| * 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 <osmocom/gsm/gsm_utils.h> |
| #include <osmocom/core/sockaddr_str.h> |
| |
| #include <osmocom/mgcp_client/mgcp_client.h> |
| |
| #include <osmocom/msc/neighbor_ident.h> |
| #include <osmocom/msc/ran_msg.h> |
| #include <osmocom/msc/mncc_call.h> |
| |
| |
| struct gsm0808_handover_required; |
| |
| struct msc_a; |
| struct ran_dec_handover_required; |
| |
| #define LOG_HO(msc_a, level, fmt, args...) \ |
| LOGPFSML((msc_a)? ((msc_a)->ho.fi ? : (msc_a)->c.fi) : NULL, \ |
| level, "%s" fmt, (msc_a->ho.fi ? "" : "HO: "), ##args) |
| |
| enum msc_ho_fsm_state { |
| MSC_HO_ST_REQUIRED, |
| MSC_HO_ST_WAIT_REQUEST_ACK, |
| MSC_HO_ST_WAIT_COMPLETE, |
| }; |
| |
| enum msc_ho_fsm_event { |
| MSC_HO_EV_RX_REQUEST_ACK, |
| MSC_HO_EV_RX_DETECT, |
| MSC_HO_EV_RX_COMPLETE, |
| MSC_HO_EV_RX_FAILURE, |
| MSC_HO_EV_MNCC_FORWARDING_COMPLETE, |
| MSC_HO_EV_MNCC_FORWARDING_FAILED, |
| }; |
| |
| struct msc_ho_state { |
| struct osmo_fsm_inst *fi; |
| struct ran_handover_required info; |
| unsigned int next_cil_idx; |
| bool subsequent_ho; |
| bool ready_to_switch_rtp; |
| bool rtp_switched_to_new_cell; |
| |
| struct { |
| enum osmo_rat_type ran_type; |
| struct gsm0808_cell_id cid; |
| struct osmo_cell_global_id cgi; |
| enum msc_neighbor_type type; |
| union { |
| struct ran_peer *ran_peer; |
| const char *msc_ipa_name; |
| }; |
| |
| /* The RTP address from Handover Request Acknowledge. |
| * Might be from AoIP Transport Layer Address from a BSC RAN peer, |
| * or from MNCC forwarding for inter-MSC handover. */ |
| struct osmo_sockaddr_str ran_remote_rtp; |
| /* The codec from Handover Request Acknowledge. */ |
| bool codec_present; |
| enum mgcp_codecs codec; |
| |
| /* Inter-MSC voice forwarding via MNCC, to the remote MSC. The Prepare Handover Response sent us the |
| * Handover Number the remote MSC assigned. This is a call to that Handover Number, via PBX. |
| * (NULL if not an inter-MSC Handover) */ |
| struct mncc_call *mncc_forwarding_to_remote_ran; |
| } new_cell; |
| |
| struct { |
| /* Saved RTP IP:port and codec in case we need to roll back */ |
| struct osmo_sockaddr_str ran_remote_rtp; |
| enum mgcp_codecs codec; |
| } old_cell; |
| }; |
| |
| void msc_ho_start(struct msc_a *msc_a, const struct ran_handover_required *ho_req); |
| |
| enum msc_neighbor_type msc_ho_find_target_cell(struct msc_a *msc_a, const struct gsm0808_cell_id *cid, |
| const struct neighbor_ident_entry **remote_msc, |
| struct ran_peer **ran_peer_from_neighbor_ident, |
| struct ran_peer **ran_peer_from_seen_cells); |