Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame^] | 1 | /* Handle a call via VGCS/VBCS (Voice Group/Broadcast Call Service). */ |
| 2 | /* |
| 3 | * (C) 2023 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de> |
| 4 | * All Rights Reserved |
| 5 | * |
| 6 | * SPDX-License-Identifier: AGPL-3.0+ |
| 7 | * |
| 8 | * Author: Andreas Eversberg |
| 9 | * |
| 10 | * This program is free software; you can redistribute it and/or modify |
| 11 | * it under the terms of the GNU Affero General Public License as published by |
| 12 | * the Free Software Foundation; either version 3 of the License, or |
| 13 | * (at your option) any later version. |
| 14 | * |
| 15 | * This program is distributed in the hope that it will be useful, |
| 16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 18 | * GNU Affero General Public License for more details. |
| 19 | * |
| 20 | * You should have received a copy of the GNU Affero General Public License |
| 21 | * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 22 | */ |
| 23 | #pragma once |
| 24 | |
| 25 | #include <osmocom/msc/transaction.h> |
| 26 | |
| 27 | #define GSM44068_ALLOC_SIZE 2048 |
| 28 | #define GSM44068_ALLOC_HEADROOM 256 |
| 29 | |
| 30 | static inline struct msgb *gsm44068_msgb_alloc_name(const char *name) |
| 31 | { |
| 32 | return msgb_alloc_headroom(GSM44068_ALLOC_SIZE, GSM44068_ALLOC_HEADROOM, name); |
| 33 | } |
| 34 | |
| 35 | /* VGCS/VBS "call control" connection to each BSS */ |
| 36 | struct vgcs_bss { |
| 37 | struct llist_head list; /* List entry */ |
| 38 | struct llist_head cell_list; /* List of cells */ |
| 39 | struct gsm_trans *trans; /* Back pointer to transaction */ |
| 40 | struct osmo_fsm_inst *fi; /* State machine of each BSS */ |
| 41 | struct ran_conn *conn; /* RAN ("SCCP") connection */ |
| 42 | enum trans_type trans_type; /* Transaction type */ |
| 43 | uint32_t callref; /* Callref */ |
| 44 | int pc; /* Point code for debug purpose */ |
| 45 | }; |
| 46 | |
| 47 | /* VGCS/VBS "resource control" connection to each cell in BSS */ |
| 48 | struct vgcs_bss_cell { |
| 49 | struct llist_head list_bss; /* List entry in vgcs_bss */ |
| 50 | struct llist_head list_mgw; /* List entry in MGW endpoint */ |
| 51 | struct vgcs_bss *bss; /* Back pointer to vgcs_bss */ |
| 52 | struct vgcs_mgw_ep *mgw; /* Back pointer to vgcs_mgw_ep */ |
| 53 | struct osmo_fsm_inst *fi; /* State machine of each cell */ |
| 54 | int cell_id; /* Id of cell (BTS) to use */ |
| 55 | struct ran_conn *conn; /* RAN ("SCCP") connection */ |
| 56 | enum trans_type trans_type; /* Transaction type */ |
| 57 | uint32_t callref; /* Callref */ |
| 58 | int call_id; /* Id of call (used for MGW connections) */ |
| 59 | int pc; /* Point code for debug purpose */ |
| 60 | bool assigned; /* Flags if assignment is complete */ |
| 61 | struct rtp_stream *rtps; /* MGW connection process */ |
| 62 | }; |
| 63 | |
| 64 | /* VGCS/VBS MGW endpoint for each call */ |
| 65 | struct vgcs_mgw_ep { |
| 66 | struct llist_head cell_list; /* List of cells with connections */ |
| 67 | struct llist_head list; /* List entry */ |
| 68 | struct osmo_fsm_inst *fi; /* State machine of each cell */ |
| 69 | struct osmo_mgcpc_ep *mgw_ep; /* MGW endpoint */ |
| 70 | }; |
| 71 | |
| 72 | /* Events for the GCC/BCC state machine. |
| 73 | * There is no primitive definition like MNGCC-* oder MNBCC-* in the standard. */ |
| 74 | enum vgcs_gcc_fsm_event { |
| 75 | /* The network sets up a call. */ |
| 76 | VGCS_GCC_EV_NET_SETUP, |
| 77 | /* The network requests termination. */ |
| 78 | VGCS_GCC_EV_NET_TERM, |
| 79 | /* The user sets up a call. */ |
| 80 | VGCS_GCC_EV_USER_SETUP, |
| 81 | /* The user requests termination. */ |
| 82 | VGCS_GCC_EV_USER_TERM, |
| 83 | /* BSS completed call establishment (all BSCs) */ |
| 84 | VGCS_GCC_EV_BSS_ESTABLISHED, |
| 85 | /* Assignment was completed. */ |
| 86 | VGCS_GCC_EV_BSS_ASSIGN_CPL, |
| 87 | /* Assignment failed. */ |
| 88 | VGCS_GCC_EV_BSS_ASSIGN_FAIL, |
| 89 | /* BSS released call establishment (all BSCs) */ |
| 90 | VGCS_GCC_EV_BSS_RELEASED, |
| 91 | /* Inactivity timeout */ |
| 92 | VGCS_GCC_EV_TIMEOUT, |
| 93 | }; |
| 94 | |
| 95 | /* 3GPP TS 44.068 6.1.2.2 States of GCC/BCC */ |
| 96 | enum vgcs_gcc_fsm_state { |
| 97 | /* No call. Initial state when instance is created. */ |
| 98 | VGCS_GCC_ST_N0_NULL = 0, |
| 99 | /* An MS wants to establish a call. */ |
| 100 | VGCS_GCC_ST_N1_CALL_INITIATED, |
| 101 | /* Call established in at least one cell. */ |
| 102 | VGCS_GCC_ST_N2_CALL_ACTIVE, |
| 103 | /* Channel activation is requested, CONNECT already sent to MS. */ |
| 104 | VGCS_GCC_ST_N3_CALL_EST_PROC, |
| 105 | /* Call termination is requested, waiting for all cells to confirm. */ |
| 106 | VGCS_GCC_ST_N4_TERMINATION_REQ, |
| 107 | }; |
| 108 | |
| 109 | const char *vgcs_bcc_gcc_state_name(struct osmo_fsm_inst *fi); |
| 110 | |
| 111 | /* Events for the VGCS/VBS "call control" state machine */ |
| 112 | enum vgcs_bss_fsm_event { |
| 113 | /* Start a VGCS/VBS call using VGCS/VBS SETUP message */ |
| 114 | VGCS_BSS_EV_SETUP, |
| 115 | /* VGCS/VBS SETUP ACK is received */ |
| 116 | VGCS_BSS_EV_SETUP_ACK, |
| 117 | /* VGCS/VBS SETUP REFUSE is received */ |
| 118 | VGCS_BSS_EV_SETUP_REFUSE, |
| 119 | /* VGCS/VBS ASSIGNMENT complete or failed */ |
| 120 | VGCS_BSS_EV_ACTIVE_OR_FAIL, |
| 121 | /* Talker request */ |
| 122 | VGCS_BSS_EV_UL_REQUEST, |
| 123 | /* Talker established uplink */ |
| 124 | VGCS_BSS_EV_UL_REQUEST_CNF, |
| 125 | /* Talker send app data */ |
| 126 | VGCS_BSS_EV_UL_APP_DATA, |
| 127 | /* Talker send signaling data */ |
| 128 | VGCS_BSS_EV_BSS_DTAP, |
| 129 | /* Talker becomes listener */ |
| 130 | VGCS_BSS_EV_UL_RELEASE, |
| 131 | /* Release channel towards BSS */ |
| 132 | VGCS_BSS_EV_CLEAR, |
| 133 | /* Channel closed from BSS */ |
| 134 | VGCS_BSS_EV_CLOSE, |
| 135 | /* Release is complete */ |
| 136 | VGCS_BSS_EV_RELEASED, |
| 137 | }; |
| 138 | |
| 139 | /* States of the VGCS/VBS "call control" state machine */ |
| 140 | enum vgcs_bss_fsm_state { |
| 141 | /* No call. Initial state when instance is created. */ |
| 142 | VGCS_BSS_ST_NULL = 0, |
| 143 | /* VGCS/VBS SETUP is sent towards BSC */ |
| 144 | VGCS_BSS_ST_SETUP, |
| 145 | /* VGCS/VBS ASSIGNMENT REQUEST is sent towards BSC */ |
| 146 | VGCS_BSS_ST_ASSIGNMENT, |
| 147 | /* VGCS/VBS is establised */ |
| 148 | VGCS_BSS_ST_ACTIVE, |
| 149 | /* CLEAR COMMAND was sent */ |
| 150 | VGCS_BSS_ST_RELEASE, |
| 151 | }; |
| 152 | |
| 153 | /* Events for the VGCS/VBS "resource control" state machine */ |
| 154 | enum vgcs_cell_fsm_event { |
| 155 | /* RTP stream gone */ |
| 156 | VGCS_CELL_EV_RTP_STREAM_GONE, |
| 157 | /* RTP stream remote addr available */ |
| 158 | VGCS_CELL_EV_RTP_STREAM_ADDR_AVAILABLE, |
| 159 | /* RTP stream established */ |
| 160 | VGCS_CELL_EV_RTP_STREAM_ESTABLISHED, |
| 161 | /* Start a VGCS/VBS channel using VGCS/VBS ASSIGNMENT message */ |
| 162 | VGCS_CELL_EV_ASSIGN, |
| 163 | /* VGCS/VBS ASSIGNMENT RESULT is received */ |
| 164 | VGCS_CELL_EV_ASSIGN_RES, |
| 165 | /* VGCS/VBS ASSIGNMENT FAILURE is received */ |
| 166 | VGCS_CELL_EV_ASSIGN_FAIL, |
| 167 | /* Release channel towards BSS */ |
| 168 | VGCS_CELL_EV_CLEAR, |
| 169 | /* Channel closed from BSS */ |
| 170 | VGCS_CELL_EV_CLOSE, |
| 171 | /* Release is complete */ |
| 172 | VGCS_CELL_EV_RELEASED, |
| 173 | }; |
| 174 | |
| 175 | /* States of the VGCS/VBS "resource control" state machine */ |
| 176 | enum vgcs_cell_fsm_state { |
| 177 | /* No call. Initial state when instance is created. */ |
| 178 | VGCS_CELL_ST_NULL = 0, |
| 179 | /* VGCS/VBS ASSIGNMENT REQUEST is sent towards BSC */ |
| 180 | VGCS_CELL_ST_ASSIGNMENT, |
| 181 | /* Channel is establised */ |
| 182 | VGCS_CELL_ST_ACTIVE, |
| 183 | /* CLEAR COMMAND was sent */ |
| 184 | VGCS_CELL_ST_RELEASE, |
| 185 | }; |
| 186 | |
| 187 | /* Events for the VGCS/VBS MGW endpoint state machine */ |
| 188 | enum vgcs_mgw_ep_fsm_event { |
| 189 | /* MGW endpoint gone */ |
| 190 | VGCS_MGW_EP_EV_FREE, |
| 191 | /* Destroy MGW endpoint */ |
| 192 | VGCS_MGW_EP_EV_CLEAR, |
| 193 | }; |
| 194 | |
| 195 | /* States of the VGCS/VBS MGW endpoint state machine */ |
| 196 | enum vgcs_mgw_ep_fsm_state { |
| 197 | VGCS_MGW_EP_ST_NULL = 0, |
| 198 | /* MGW endpoint allocated */ |
| 199 | VGCS_MGW_EP_ST_ACTIVE, |
| 200 | }; |
| 201 | |
| 202 | const char *gsm44068_group_id_string(uint32_t callref); |
| 203 | |
| 204 | struct gcr; |
| 205 | |
| 206 | int gsm44068_rcv_rr(struct msc_a *msc_a, struct msgb *msg); |
| 207 | int gsm44068_rcv_bcc_gcc(struct msc_a *msc_a, struct gsm_trans *trans, struct msgb *msg); |
| 208 | const char *vgcs_vty_initiate(struct gsm_network *gsmnet, struct gcr *gcr); |
| 209 | const char *vgcs_vty_terminate(struct gsm_network *gsmnet, struct gcr *gcr); |
| 210 | void gsm44068_bcc_gcc_trans_free(struct gsm_trans *trans); |
| 211 | |
| 212 | void vgcs_vbs_setup_ack(struct vgcs_bss *bss, const struct ran_msg *ran_msg); |
| 213 | void vgcs_vbs_setup_refuse(struct vgcs_bss *bss, const struct ran_msg *ran_msg); |
| 214 | void vgcs_vbs_assign_result(struct vgcs_bss_cell *cell, const struct ran_msg *ran_msg); |
| 215 | void vgcs_vbs_assign_fail(struct vgcs_bss_cell *cell, const struct ran_msg *ran_msg); |
| 216 | void vgcs_vbs_queuing_ind(struct vgcs_bss_cell *cell); |
| 217 | void vgcs_uplink_request(struct vgcs_bss *bss, const struct ran_msg *ran_msg); |
| 218 | void vgcs_uplink_request_cnf(struct vgcs_bss *bss, const struct ran_msg *ran_msg); |
| 219 | void vgcs_app_data(struct vgcs_bss *bss, const struct ran_msg *ran_msg); |
| 220 | void vgcs_bss_dtap(struct vgcs_bss *bss, const struct ran_msg *ran_msg); |
| 221 | void vgcs_uplink_release_ind(struct vgcs_bss *bss, const struct ran_msg *ran_msg); |
| 222 | void vgcs_vbs_assign_status(struct vgcs_bss_cell *cell, const struct ran_msg *ran_msg); |
| 223 | void vgcs_vbs_clear_req_channel(struct vgcs_bss_cell *cell, const struct ran_msg *ran_msg); |
| 224 | void vgcs_vbs_clear_cpl_channel(struct vgcs_bss_cell *cell, const struct ran_msg *ran_msg); |
| 225 | void vgcs_vbs_clear_req(struct vgcs_bss *bss, const struct ran_msg *ran_msg); |
| 226 | void vgcs_vbs_clear_cpl(struct vgcs_bss *bss, const struct ran_msg *ran_msg); |
| 227 | void vgcs_vbs_caller_assign_cpl(struct gsm_trans *trans); |
| 228 | void vgcs_vbs_caller_assign_fail(struct gsm_trans *trans); |