Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 1 | /* Handle VGCS/VBCS calls. (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 | |
| 24 | /* The process consists of four state machines: |
| 25 | * |
| 26 | * The call control state machine "GCC" handles the voice group/broadcast call. |
| 27 | * There is one instance for every call. It is mainly controlled by the calling |
| 28 | * subscriber. The state machine is described in 3GPP TS 44.068 / 44.069. |
| 29 | * One SCCP connection to the calling subscriber is associated with the state |
| 30 | * machine. Once the calling subscriber leaves or is assigned to the VGCS/VBS |
| 31 | * channel, the association to the MSC-A role is removed and the SCCP connection |
| 32 | * is closed. The state machine with the transaction still exists until the end |
| 33 | * of the call. |
| 34 | * |
| 35 | * The BSS control state machine "vgcs_bss_fsm" handles the call in each BSC. |
| 36 | * There are as many instances as there are BSCs where the call is placed to. |
| 37 | * The instances are linked to the call control in a 1:n relation. |
| 38 | * One SCCP connection for every BSC is associated with the state machine. |
| 39 | * It sets up the call in the BSC and handles the uplink control and signaling |
| 40 | * with the talking phone. |
| 41 | * |
| 42 | * The resource controling state machine "vgcs_cell_fsm" handles the channel for |
| 43 | * each BTS that has a VGCS for the call. The instances are linked to the BSS |
| 44 | * control in a 1:n relation. |
| 45 | * One SCCP connection for every cell is associated with each list entry. |
| 46 | * It assigns the VGCS/VBS channel and the conference bridge in the MGW. |
| 47 | * |
| 48 | * The MGW endpoint state machine "vgcs_mgw_ep_fsm" handles the endpoint |
| 49 | * connection for each call. It controls the clearing of the MGW connections |
| 50 | * in case of endpoint failure. All instances of the resource controlling state |
| 51 | * machine are linked to this state machine in a 1:n relation. |
| 52 | * |
| 53 | * Setup of a call: |
| 54 | * |
| 55 | * When the calling subscriber dials a group/broadcast call, the GCR is checked |
| 56 | * for an existing Group ID. If it exists, the call is setup towards the a given |
| 57 | * list of MSCs for this Group ID. Also the channels are assigned for a given |
| 58 | * list of cells for this Group ID. |
| 59 | * The call can also be initiated via VTY. |
| 60 | * |
| 61 | * Then the calling subscriber is assigned to the VGCS channel of the same cell |
| 62 | * where the call was initialized. Afterwards the call is connected. The calling |
| 63 | * subscriber may then stay on the uplink or release it. |
| 64 | * |
| 65 | * Uplink control: |
| 66 | * |
| 67 | * Any BSC may indicate a talking subscriber. If there is no talking subscriber |
| 68 | * yet, the uplink is granted, otherwise it is rejected. If the uplink is in |
| 69 | * use on one BSC, all other BSCs will be blocked. If the uplink becomes free, |
| 70 | * all other BSCs will be unblocked. |
| 71 | * |
| 72 | * Termination of the call: |
| 73 | * |
| 74 | * The calling subscriber accesses the uplink. The it sends a termination |
| 75 | * request. This request is acknowledged by a termination command towards |
| 76 | * the calling subscriber. The call is cleared. |
| 77 | * The call can also be terminated via VTY and/or a timeout. |
| 78 | * |
| 79 | */ |
| 80 | |
| 81 | #include <osmocom/core/utils.h> |
| 82 | #include <osmocom/core/fsm.h> |
| 83 | #include <osmocom/gsm/protocol/gsm_44_068.h> |
| 84 | #include <osmocom/sigtran/sccp_helpers.h> |
| 85 | #include <osmocom/mgcp_client/mgcp_client_endpoint_fsm.h> |
| 86 | |
| 87 | #include <osmocom/msc/gsm_data.h> |
| 88 | #include <osmocom/msc/sccp_ran.h> |
| 89 | #include <osmocom/msc/ran_infra.h> |
| 90 | #include <osmocom/msc/ran_peer.h> |
| 91 | #include <osmocom/msc/ran_msg_a.h> |
| 92 | #include <osmocom/msc/msub.h> |
| 93 | #include <osmocom/msc/debug.h> |
| 94 | #include <osmocom/msc/msc_a.h> |
| 95 | #include <osmocom/msc/vlr.h> |
| 96 | #include <osmocom/msc/rtp_stream.h> |
| 97 | #include <osmocom/msc/codec_mapping.h> |
| 98 | #include <osmocom/msc/msc_vgcs.h> |
| 99 | #include <osmocom/msc/asci_gcr.h> |
| 100 | |
| 101 | #define S(x) (1 << (x)) |
| 102 | |
| 103 | #define LOG_GCC(trans, level, fmt, args...) \ |
| 104 | LOGP((trans) ? ((trans->type == TRANS_GCC) ? DGCC : DBCC) : DASCI, level, \ |
| 105 | (trans) ? ((trans->type == TRANS_GCC) ? ("GCC callref %s: " fmt) : ("BCC callref %s: " fmt)) : "%s" fmt, \ |
| 106 | (trans) ? gsm44068_group_id_string(trans->callref) : "", ##args) |
| 107 | #define LOG_BSS(bss, level, fmt, args...) \ |
| 108 | LOGP(DASCI, level, \ |
| 109 | (bss->trans_type == TRANS_GCC) ? ("GCC callref %s, BSS #%s: " fmt) : ("BCC callref %s, BSS #%s: " fmt), \ |
| 110 | gsm44068_group_id_string(bss->callref), osmo_ss7_pointcode_print(NULL, bss->pc), ##args) |
| 111 | #define LOG_CELL(cell, level, fmt, args...) \ |
| 112 | LOGP(DASCI, level, \ |
| 113 | (cell->trans_type == TRANS_GCC) ? ("GCC callref %s, BSS #%s, CID %d: " fmt) \ |
| 114 | : ("BCC callref %s, BSS #%s, CID %d: " fmt), \ |
| 115 | gsm44068_group_id_string(cell->callref), osmo_ss7_pointcode_print(NULL, cell->pc), cell->cell_id, ##args) |
| 116 | |
| 117 | static struct osmo_fsm vgcs_bcc_fsm; |
| 118 | static struct osmo_fsm vgcs_gcc_fsm; |
| 119 | static struct osmo_fsm vgcs_bss_fsm; |
| 120 | static struct osmo_fsm vgcs_cell_fsm; |
| 121 | static struct osmo_fsm vgcs_mgw_ep_fsm; |
| 122 | |
| 123 | static __attribute__((constructor)) void vgcs_fsm_init(void) |
| 124 | { |
| 125 | OSMO_ASSERT(osmo_fsm_register(&vgcs_bcc_fsm) == 0); |
| 126 | OSMO_ASSERT(osmo_fsm_register(&vgcs_gcc_fsm) == 0); |
| 127 | OSMO_ASSERT(osmo_fsm_register(&vgcs_bss_fsm) == 0); |
| 128 | OSMO_ASSERT(osmo_fsm_register(&vgcs_cell_fsm) == 0); |
| 129 | OSMO_ASSERT(osmo_fsm_register(&vgcs_mgw_ep_fsm) == 0); |
| 130 | } |
| 131 | |
| 132 | const char *gsm44068_group_id_string(uint32_t callref) |
| 133 | { |
| 134 | static char string[9]; |
| 135 | |
| 136 | snprintf(string, sizeof(string), "%08u", callref); |
| 137 | string[sizeof(string) - 1] = '\0'; |
| 138 | |
| 139 | return string; |
| 140 | } |
| 141 | |
| 142 | /* Resolve ran peer from point-code */ |
| 143 | static struct ran_peer *ran_peer_for_pc(struct gsm_network *msc_network, int pc) |
| 144 | { |
| 145 | struct sccp_ran_inst *sri; |
| 146 | struct osmo_sccp_addr addr = {}; |
| 147 | struct ran_peer *rp; |
| 148 | |
| 149 | sri = msc_network->a.sri; |
| 150 | if (!osmo_sccp_get_ss7(sri->sccp)) { |
| 151 | LOGP(DASCI, LOGL_ERROR, "No SS7???\n"); |
| 152 | return NULL; |
| 153 | } |
| 154 | osmo_sccp_make_addr_pc_ssn(&addr, pc, sri->ran->ssn); |
| 155 | rp = ran_peer_find_by_addr(sri, &addr); |
| 156 | |
| 157 | return rp; |
| 158 | } |
| 159 | |
| 160 | /* Encode message and send towards BSC. */ |
| 161 | int ran_encode_and_send(struct osmo_fsm_inst *fi, struct ran_msg *ran_msg, struct ran_conn *conn, bool initial) |
| 162 | { |
| 163 | struct msgb *l3_msg; |
| 164 | int rc; |
| 165 | |
| 166 | l3_msg = ran_a_encode(fi, ran_msg); |
| 167 | if (!l3_msg) { |
| 168 | LOGP(DASCI, LOGL_ERROR, "ran_a_encode() failed.\n"); |
| 169 | return -EINVAL; |
| 170 | } |
| 171 | rc = ran_conn_down_l2_co(conn, l3_msg, initial); |
| 172 | msgb_free(l3_msg); |
| 173 | |
| 174 | return rc; |
| 175 | } |
| 176 | |
| 177 | /* Transmit DTAP message to talker |
| 178 | * This is used for sending group/broadcast call control messages. */ |
| 179 | int tx_dtap_to_talker(struct vgcs_bss *bss, struct msgb *l3_msg) |
| 180 | { |
| 181 | struct ran_msg ran_msg; |
| 182 | struct gsm48_hdr *gh = msgb_l3(l3_msg) ? : l3_msg->data; |
| 183 | uint8_t pdisc = gsm48_hdr_pdisc(gh); |
| 184 | int rc; |
| 185 | |
| 186 | |
| 187 | LOG_BSS(bss, LOGL_DEBUG, "Sending DTAP: %s %s\n", |
| 188 | gsm48_pdisc_name(pdisc), gsm48_pdisc_msgtype_name(pdisc, gsm48_hdr_msg_type(gh))); |
| 189 | |
| 190 | ran_msg = (struct ran_msg){ |
| 191 | .msg_type = RAN_MSG_DTAP, |
| 192 | .dtap = l3_msg, |
| 193 | }; |
| 194 | |
| 195 | rc = ran_encode_and_send(bss->fi, &ran_msg, bss->conn, false); |
| 196 | |
| 197 | return rc; |
| 198 | } |
| 199 | |
| 200 | /* |
| 201 | * GCC/BCC Message transcoding |
| 202 | */ |
| 203 | |
| 204 | static void _add_cause_ie(struct msgb *msg, uint8_t cause, uint8_t *diag, uint8_t diag_len) |
| 205 | { |
| 206 | uint8_t *ie = msgb_put(msg, 2 + diag_len); |
| 207 | |
| 208 | ie[0] = 1 + diag_len; |
| 209 | ie[1] = cause; |
| 210 | if (diag && diag_len) { |
| 211 | ie[1] |= 0x80; |
| 212 | memcpy(ie + 2, diag, diag_len); |
| 213 | } |
| 214 | } |
| 215 | |
| 216 | static void _add_callref_ie(struct msgb *msg, uint32_t callref, bool with_prio, uint8_t prio) |
| 217 | { |
| 218 | uint32_t ie; |
| 219 | |
| 220 | ie = callref << 5; |
| 221 | if (with_prio) |
| 222 | ie |= 0x10 | (prio << 1); |
| 223 | msgb_put_u32(msg, ie); |
| 224 | } |
| 225 | |
| 226 | static int _msg_too_short(void) |
| 227 | { |
| 228 | LOGP(DASCI, LOGL_ERROR, "MSG too short.\n"); |
| 229 | return -EINVAL; |
| 230 | } |
| 231 | |
| 232 | static int _ie_invalid(void) |
| 233 | { |
| 234 | LOGP(DASCI, LOGL_ERROR, "IE invalid.\n"); |
| 235 | return -EINVAL; |
| 236 | } |
| 237 | |
| 238 | static int _rx_callref(uint8_t *ie, unsigned int remaining_len, uint32_t *callref, bool *with_prio, uint8_t *prio) |
| 239 | { |
| 240 | uint8_t ie_len; |
| 241 | |
| 242 | ie_len = sizeof(uint32_t); |
| 243 | if (remaining_len < ie_len) |
| 244 | return _msg_too_short(); |
| 245 | *callref = osmo_load32be(ie) >> 5; |
| 246 | if (ie[3] & 0x10) { |
| 247 | *with_prio = true; |
| 248 | *prio = (ie[3] >> 1) & 0x7; |
| 249 | } else |
| 250 | *with_prio = false; |
| 251 | |
| 252 | return ie_len; |
| 253 | } |
| 254 | |
| 255 | /* 3GPP TS 44.068 Clause 8.1 */ |
| 256 | static int gsm44068_tx_connect(struct gsm_trans *trans, uint8_t pdisc, uint32_t callref, bool with_prio, uint8_t prio, |
| 257 | uint8_t oi, uint8_t talker_prio, bool with_sms, uint8_t sms_dc, uint8_t sms_gp) |
| 258 | { |
| 259 | struct msgb *msg = gsm44068_msgb_alloc_name("GSM 44.068 TX CONNECT"); |
| 260 | struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh)); |
| 261 | uint8_t ie; |
| 262 | |
| 263 | gh->proto_discr = pdisc; |
| 264 | gh->msg_type = OSMO_GSM44068_MSGT_CONNECT; |
| 265 | _add_callref_ie(msg, callref, with_prio, prio); |
| 266 | ie = (talker_prio << 4) | oi; |
| 267 | msgb_put_u8(msg, ie); |
| 268 | if (with_sms) { |
| 269 | ie = OSMO_GSM44068_IEI_SMS_INDICATIONS | (sms_dc << 1) | sms_gp; |
| 270 | msgb_put_u8(msg, ie); |
| 271 | } |
| 272 | |
| 273 | /* Send to calling subscriber, depending on the link he is. */ |
| 274 | if (trans->msc_a) |
| 275 | return msc_a_tx_dtap_to_i(trans->msc_a, msg); |
| 276 | if (trans->gcc.uplink_bss) |
| 277 | return tx_dtap_to_talker(trans->gcc.uplink_bss, msg); |
| 278 | msgb_free(msg); |
| 279 | return -EIO; |
| 280 | } |
| 281 | |
| 282 | /* The Get Status procedure is not used by the current implementation. |
| 283 | * It is commented out, so it can be used in the future. |
| 284 | * The idea is to have a complete set of GCC/BCC message transcoding. |
| 285 | */ |
| 286 | #if 0 |
| 287 | /* 3GPP TS 44.068 Clause 8.2 */ |
| 288 | static int gsm44068_tx_get_status(struct gsm_trans *trans, uint8_t pdisc, struct osmo_mobile_identity *mi) |
| 289 | { |
| 290 | struct msgb *msg = gsm44068_msgb_alloc_name("GSM 44.068 TX GET STATUS"); |
| 291 | struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh)); |
| 292 | |
| 293 | gh->proto_discr = pdisc; |
| 294 | gh->msg_type = OSMO_GSM44068_MSGT_GET_STATUS; |
| 295 | if (mi) { |
| 296 | uint8_t *l; |
| 297 | int rc; |
| 298 | |
| 299 | l = msgb_tl_put(msg, OSMO_GSM44068_IEI_MOBILE_IDENTITY); |
| 300 | rc = osmo_mobile_identity_encode_msgb(msg, mi, false); |
| 301 | if (rc < 0) { |
| 302 | msgb_free(msg); |
| 303 | return -EINVAL; |
| 304 | } |
| 305 | *l = rc; |
| 306 | } |
| 307 | |
| 308 | /* Send to calling subscriber, depending on the link he is. */ |
| 309 | if (trans->msc_a) |
| 310 | return msc_a_tx_dtap_to_i(trans->msc_a, msg); |
| 311 | if (trans->gcc.uplink_bss) |
| 312 | return tx_dtap_to_talker(trans->gcc.uplink_bss, msg); |
| 313 | msgb_free(msg); |
| 314 | return -EIO; |
| 315 | } |
| 316 | #endif |
| 317 | |
| 318 | /* 3GPP TS 44.068 Clause 8.3 and 8.3a */ |
| 319 | static int gsm44068_rx_immediate_setup(struct msgb *msg, uint8_t *talker_prio, uint8_t *key_seq, |
| 320 | struct gsm48_classmark2 *cm2, struct osmo_mobile_identity *mi, |
| 321 | uint32_t *callref, bool *with_prio, uint8_t *prio, char *user_user) |
| 322 | { |
| 323 | struct gsm48_hdr *gh = msgb_l3(msg); |
| 324 | unsigned int remaining_len = msgb_l3len(msg) - sizeof(*gh); |
| 325 | uint8_t *ie = gh->data; |
| 326 | uint8_t ie_len; |
| 327 | uint64_t otdi; |
| 328 | int i; |
| 329 | int rc; |
| 330 | |
| 331 | /* Talker priority / Cyphering key sequence */ |
| 332 | if (remaining_len < 1) |
| 333 | return _msg_too_short(); |
| 334 | *talker_prio = ie[0] & 0x07; |
| 335 | *key_seq = (ie[0] >> 4) & 0x07; |
| 336 | remaining_len -= 1; |
| 337 | ie += 1; |
| 338 | |
| 339 | /* Mobile station classmark 2 */ |
| 340 | if (remaining_len < 4) |
| 341 | return _msg_too_short(); |
| 342 | ie_len = ie[0]; |
| 343 | if (remaining_len < ie_len + 1) |
| 344 | return _msg_too_short(); |
| 345 | if (ie_len != 3) |
| 346 | return _ie_invalid(); |
| 347 | memcpy(cm2, ie + 1, ie_len); |
| 348 | remaining_len -= ie_len + 1; |
| 349 | ie += ie_len + 1; |
| 350 | |
| 351 | /* Mobile indentity */ |
| 352 | if (gh->msg_type == OSMO_GSM44068_MSGT_IMMEDIATE_SETUP) { |
| 353 | /* IMMEDIATE SETUP uses IMSI/TMSI */ |
| 354 | if (remaining_len < 2) |
| 355 | return _msg_too_short(); |
| 356 | ie_len = ie[0]; |
| 357 | if (remaining_len < ie_len + 1) |
| 358 | return _msg_too_short(); |
| 359 | rc = osmo_mobile_identity_decode(mi, ie + 1, ie_len, false); |
| 360 | if (rc) { |
| 361 | LOGP(DMM, LOGL_ERROR, "Failure to decode Mobile Identity in GCC/BCC IMMEDDIATE SETUP" |
| 362 | " (rc=%d)\n", rc); |
| 363 | return -EINVAL; |
| 364 | } |
| 365 | remaining_len -= ie_len + 1; |
| 366 | ie += ie_len + 1; |
| 367 | } else { |
| 368 | /* IMMEDIATE SETUP 2 uses TMSI only */ |
| 369 | if (remaining_len < 4) |
| 370 | return _msg_too_short(); |
| 371 | mi->type = GSM_MI_TYPE_TMSI; |
| 372 | mi->tmsi = osmo_load32be(ie); |
| 373 | remaining_len -= 4; |
| 374 | ie += 4; |
| 375 | } |
| 376 | |
| 377 | /* Call reference */ |
| 378 | rc = _rx_callref(ie, remaining_len, callref, with_prio, prio); |
| 379 | if (rc < 0) |
| 380 | return rc; |
| 381 | remaining_len -= rc; |
| 382 | ie += rc; |
| 383 | |
| 384 | /* OTID */ |
| 385 | if (gh->msg_type == OSMO_GSM44068_MSGT_IMMEDIATE_SETUP_2 && user_user) { |
| 386 | ie_len = 5; |
| 387 | if (remaining_len < ie_len) |
| 388 | return _msg_too_short(); |
| 389 | otdi = osmo_load32be(ie + 1) | ((uint64_t)ie[0] << 32); |
| 390 | |
| 391 | for (i = 0; i < 12; i++) { |
| 392 | user_user[i] = (otdi % 10) + '0'; |
| 393 | otdi /= 10; |
| 394 | } |
| 395 | user_user[i] = '\0'; |
| 396 | remaining_len -= ie_len; |
| 397 | ie += ie_len; |
| 398 | } else if (user_user) |
| 399 | user_user[0] = '\0'; |
| 400 | |
| 401 | return 0; |
| 402 | } |
| 403 | |
| 404 | /* 3GPP TS 44.068 Clause 8.4 */ |
| 405 | static int gsm44068_tx_set_parameter(struct gsm_trans *trans, uint8_t pdisc, uint8_t da, uint8_t ua, uint8_t comm, |
| 406 | uint8_t oi) |
| 407 | { |
| 408 | struct msgb *msg = gsm44068_msgb_alloc_name("GSM 44.068 TX SET PARAMETER"); |
| 409 | struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh)); |
| 410 | uint8_t ie; |
| 411 | |
| 412 | gh->proto_discr = pdisc; |
| 413 | gh->msg_type = OSMO_GSM44068_MSGT_SET_PARAMETER; |
| 414 | ie = (da << 3) | (ua << 2) | (comm << 1) | oi; |
| 415 | msgb_put_u8(msg, ie); |
| 416 | |
| 417 | /* Send to calling subscriber, depending on the link he is. */ |
| 418 | if (trans->msc_a) |
| 419 | return msc_a_tx_dtap_to_i(trans->msc_a, msg); |
| 420 | if (trans->gcc.uplink_bss) |
| 421 | return tx_dtap_to_talker(trans->gcc.uplink_bss, msg); |
| 422 | msgb_free(msg); |
| 423 | return -EIO; |
| 424 | } |
| 425 | |
| 426 | /* 3GPP TS 44.068 Clause 8.5 */ |
| 427 | static int gsm44068_rx_setup(struct msgb *msg, bool *with_talker_prio, uint8_t *talker_prio, |
| 428 | uint32_t *callref, bool *with_prio, uint8_t *prio, char *user_user) |
| 429 | { |
| 430 | struct gsm48_hdr *gh = msgb_l3(msg); |
| 431 | unsigned int remaining_len = msgb_l3len(msg) - sizeof(*gh); |
| 432 | uint8_t *ie = gh->data; |
| 433 | struct tlv_parsed tp; |
| 434 | struct tlv_p_entry *tlv; |
| 435 | int rc; |
| 436 | |
| 437 | /* Call reference */ |
| 438 | rc = _rx_callref(ie, remaining_len, callref, with_prio, prio); |
| 439 | if (rc < 0) |
| 440 | return rc; |
| 441 | remaining_len -= rc; |
| 442 | ie += rc; |
| 443 | |
| 444 | rc = tlv_parse(&tp, &osmo_gsm44068_att_tlvdef, ie, remaining_len, 0, 0); |
| 445 | if (rc < 0) |
| 446 | return _ie_invalid(); |
| 447 | |
| 448 | /* User-user */ |
| 449 | tlv = TLVP_GET(&tp, OSMO_GSM44068_IEI_USER_USER); |
| 450 | if (tlv && tlv->len && tlv->len <= 1 + 12 && user_user) { |
| 451 | memcpy(user_user, tlv->val, tlv->len - 1); |
| 452 | user_user[tlv->len - 1] = '\0'; |
| 453 | } |
| 454 | |
| 455 | /* Talker priority */ |
| 456 | tlv = TLVP_GET(&tp, OSMO_GSM44068_IEI_TALKER_PRIORITY); |
| 457 | if (tlv && tlv->len) { |
| 458 | *with_talker_prio = true; |
| 459 | *talker_prio = tlv->val[0] & 0x07; |
| 460 | } else |
| 461 | *with_talker_prio = false; |
| 462 | |
| 463 | return 0; |
| 464 | } |
| 465 | |
| 466 | /* 3GPP TS 44.068 Clause 8.6 */ |
| 467 | static int gsm44068_rx_status(struct msgb *msg, uint8_t *cause, uint8_t *diag, uint8_t *diag_len, |
| 468 | bool *with_call_state, enum osmo_gsm44068_call_state *call_state, |
| 469 | bool *with_state_attrs, uint8_t *da, uint8_t *ua, uint8_t *comm, uint8_t *oi) |
| 470 | { |
| 471 | struct gsm48_hdr *gh = msgb_l3(msg); |
| 472 | unsigned int remaining_len = msgb_l3len(msg) - sizeof(*gh); |
| 473 | uint8_t *ie = gh->data; |
| 474 | uint8_t ie_len; |
| 475 | struct tlv_parsed tp; |
| 476 | struct tlv_p_entry *tlv; |
| 477 | int rc; |
| 478 | |
| 479 | /* Cause */ |
| 480 | if (remaining_len < 2 || ie[0] < remaining_len - 2) |
| 481 | return _msg_too_short(); |
| 482 | ie_len = ie[0]; |
| 483 | if (remaining_len < ie_len + 1) |
| 484 | return _msg_too_short(); |
| 485 | if (ie_len < 1) |
| 486 | return _ie_invalid(); |
| 487 | *cause = ie[1] & 0x7f; |
| 488 | *diag_len = ie_len - 1; |
| 489 | if (*diag_len) |
| 490 | memcpy(diag, ie + 2, ie_len - 1); |
| 491 | remaining_len -= ie_len + 1; |
| 492 | ie += ie_len + 1; |
| 493 | |
| 494 | rc = tlv_parse(&tp, &osmo_gsm44068_att_tlvdef, ie, remaining_len, 0, 0); |
| 495 | if (rc < 0) |
| 496 | return _ie_invalid(); |
| 497 | |
| 498 | /* Call state */ |
| 499 | tlv = TLVP_GET(&tp, OSMO_GSM44068_IEI_CALL_STATE); |
| 500 | if (tlv) { |
| 501 | *with_call_state = true; |
| 502 | *call_state = tlv->val[0] & 0x7; |
| 503 | } else |
| 504 | *with_call_state = false; |
| 505 | |
| 506 | /* State attributes */ |
| 507 | tlv = TLVP_GET(&tp, OSMO_GSM44068_IEI_STATE_ATTRIBUTES); |
| 508 | if (tlv) { |
| 509 | *with_state_attrs = true; |
| 510 | *da = (tlv->val[0] >> 3) & 0x1; |
| 511 | *ua = (tlv->val[0] >> 2) & 0x1; |
| 512 | *comm = (tlv->val[0] >> 1) & 0x1; |
| 513 | *oi = tlv->val[0] & 0x1; |
| 514 | } else |
| 515 | *with_state_attrs = false; |
| 516 | |
| 517 | return 0; |
| 518 | } |
| 519 | |
| 520 | /* 3GPP TS 44.068 Clause 8.7 and 8.8 */ |
| 521 | static int gsm44068_tx_termination(struct msc_a *msc_a, struct vgcs_bss *bss, uint8_t pdisc, uint8_t msg_type, |
| 522 | uint8_t cause, uint8_t *diag, uint8_t diag_len) |
| 523 | { |
| 524 | struct msgb *msg = gsm44068_msgb_alloc_name("GSM 44.068 TX TERMINATION"); |
| 525 | struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh)); |
| 526 | |
| 527 | gh->proto_discr = pdisc; |
| 528 | gh->msg_type = msg_type; |
| 529 | _add_cause_ie(msg, cause, diag, diag_len); |
| 530 | |
| 531 | /* Send to calling subscriber, depending on the link he is. */ |
| 532 | if (msc_a) |
| 533 | return msc_a_tx_dtap_to_i(msc_a, msg); |
| 534 | if (bss) |
| 535 | return tx_dtap_to_talker(bss, msg); |
| 536 | msgb_free(msg); |
| 537 | return -EIO; |
| 538 | } |
| 539 | |
| 540 | /* 3GPP TS 44.068 Clause 8.9 */ |
| 541 | static int gsm44068_rx_termination_req(struct msgb *msg, uint32_t *callref, bool *with_prio, uint8_t *prio, |
| 542 | bool *with_talker_prio, uint8_t *talker_prio) |
| 543 | { |
| 544 | struct gsm48_hdr *gh = msgb_l3(msg); |
| 545 | unsigned int remaining_len = msgb_l3len(msg) - sizeof(*gh); |
| 546 | uint8_t *ie = gh->data; |
| 547 | struct tlv_parsed tp; |
| 548 | struct tlv_p_entry *tlv; |
| 549 | int rc; |
| 550 | |
| 551 | /* Call reference */ |
| 552 | rc = _rx_callref(ie, remaining_len, callref, with_prio, prio); |
| 553 | if (rc < 0) |
| 554 | return rc; |
| 555 | remaining_len -= rc; |
| 556 | ie += rc; |
| 557 | |
| 558 | rc = tlv_parse(&tp, &osmo_gsm44068_att_tlvdef, ie, remaining_len, 0, 0); |
| 559 | if (rc < 0) |
| 560 | return _ie_invalid(); |
| 561 | |
| 562 | /* Talker priority */ |
| 563 | tlv = TLVP_GET(&tp, OSMO_GSM44068_IEI_TALKER_PRIORITY); |
| 564 | if (tlv && tlv->len) { |
| 565 | *with_talker_prio = true; |
| 566 | *talker_prio = tlv->val[0] & 0x07; |
| 567 | } else |
| 568 | *with_talker_prio = false; |
| 569 | |
| 570 | return 0; |
| 571 | } |
| 572 | |
| 573 | /* |
| 574 | * GCC/BCC state machine - handles calling subscriber process |
| 575 | */ |
| 576 | |
| 577 | static const struct value_string vgcs_gcc_fsm_event_names[] = { |
| 578 | OSMO_VALUE_STRING(VGCS_GCC_EV_NET_SETUP), |
| 579 | OSMO_VALUE_STRING(VGCS_GCC_EV_NET_TERM), |
| 580 | OSMO_VALUE_STRING(VGCS_GCC_EV_USER_SETUP), |
| 581 | OSMO_VALUE_STRING(VGCS_GCC_EV_USER_TERM), |
| 582 | OSMO_VALUE_STRING(VGCS_GCC_EV_BSS_ESTABLISHED), |
| 583 | OSMO_VALUE_STRING(VGCS_GCC_EV_BSS_ASSIGN_CPL), |
| 584 | OSMO_VALUE_STRING(VGCS_GCC_EV_BSS_ASSIGN_FAIL), |
| 585 | OSMO_VALUE_STRING(VGCS_GCC_EV_BSS_RELEASED), |
| 586 | OSMO_VALUE_STRING(VGCS_GCC_EV_TIMEOUT), |
| 587 | { } |
| 588 | }; |
| 589 | |
| 590 | static int gcc_establish_bss(struct gsm_trans *trans) |
| 591 | { |
| 592 | struct gsm_network *net = trans->net; |
| 593 | struct vgcs_mgw_ep *mgw = NULL; |
| 594 | struct mgcp_client *mgcp_client; |
| 595 | struct gcr *gcr; |
| 596 | struct gcr_bss *b; |
| 597 | struct gcr_cell *c; |
| 598 | struct vgcs_bss *bss; |
| 599 | struct vgcs_bss_cell *cell; |
| 600 | struct osmo_fsm_inst *fi; |
| 601 | struct ran_peer *rp; |
| 602 | |
| 603 | /* Failure should not happen, because it has been checked before. */ |
| 604 | gcr = gcr_by_callref(trans->net, trans->type, trans->callref); |
| 605 | if (!gcr) |
| 606 | return -EINVAL; |
| 607 | |
| 608 | /* Allocate MGW endpoint. */ |
| 609 | mgcp_client = mgcp_client_pool_get(trans->net->mgw.mgw_pool); |
| 610 | if (!mgcp_client) { |
| 611 | LOG_GCC(trans, LOGL_ERROR, "No MGW client, please check config.\n"); |
| 612 | goto err_mgw; |
| 613 | } |
| 614 | fi = osmo_fsm_inst_alloc(&vgcs_mgw_ep_fsm, net, NULL, LOGL_DEBUG, NULL); |
| 615 | if (!fi) { |
| 616 | LOG_GCC(trans, LOGL_ERROR, "No memory for VGCS MSG state machine.\n"); |
| 617 | goto err_mgw; |
| 618 | } |
| 619 | osmo_fsm_inst_update_id(fi, "vgcs-mgw-ep"); |
| 620 | osmo_fsm_inst_state_chg(fi, VGCS_MGW_EP_ST_ACTIVE, 0, 0); |
| 621 | mgw = talloc_zero(fi, struct vgcs_mgw_ep); |
| 622 | if (!mgw) { |
| 623 | LOG_GCC(trans, LOGL_ERROR, "No memory for MGW ep structure.\n"); |
| 624 | osmo_fsm_inst_free(fi); |
| 625 | goto err_mgw; |
| 626 | } |
| 627 | mgw->fi = fi; |
| 628 | fi->priv = mgw; |
| 629 | INIT_LLIST_HEAD(&mgw->cell_list); |
| 630 | mgw->mgw_ep = osmo_mgcpc_ep_alloc(mgw->fi, VGCS_MGW_EP_EV_FREE, |
| 631 | mgcp_client, trans->net->mgw.tdefs, mgw->fi->id, |
| 632 | "%s", mgcp_client_rtpbridge_wildcard(mgcp_client)); |
| 633 | if (!mgw->mgw_ep) { |
| 634 | LOG_GCC(trans, LOGL_ERROR, "No memory for MGW endpoint state machine.\n"); |
| 635 | goto err_mgw; |
| 636 | } |
| 637 | |
| 638 | /* Create BSS list structures. */ |
Andreas Eversberg | cc7b7b8 | 2023-07-27 13:17:50 +0200 | [diff] [blame] | 639 | LOG_GCC(trans, LOGL_DEBUG, "Creating BSS list structure with cell list structures.\n"); |
Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 640 | llist_for_each_entry(b, &gcr->bss_list, list) { |
| 641 | LOG_GCC(trans, LOGL_DEBUG, " -> BSS with PC %s.\n", osmo_ss7_pointcode_print(NULL, b->pc)); |
| 642 | /* Resolve ran_peer. */ |
| 643 | rp = ran_peer_for_pc(trans->net, b->pc); |
| 644 | if (!rp) { |
| 645 | LOG_GCC(trans, LOGL_ERROR, "Failed to resolve point code %s, skipping BSS!\n", |
| 646 | osmo_ss7_pointcode_print(NULL, b->pc)); |
| 647 | continue; |
| 648 | } |
| 649 | /* Create state machine. */ |
| 650 | fi = osmo_fsm_inst_alloc(&vgcs_bss_fsm, net, NULL, LOGL_DEBUG, NULL); |
| 651 | if (!fi) { |
| 652 | LOG_GCC(trans, LOGL_ERROR, "No memory for state machine.\n"); |
| 653 | break; |
| 654 | } |
| 655 | /* Create call structure. */ |
| 656 | bss = talloc_zero(fi, struct vgcs_bss); |
| 657 | if (!bss) { |
| 658 | LOG_GCC(trans, LOGL_ERROR, "No memory for BSS call structure.\n"); |
| 659 | osmo_fsm_inst_free(fi); |
| 660 | break; |
| 661 | } |
| 662 | bss->fi = fi; |
| 663 | fi->priv = bss; |
| 664 | INIT_LLIST_HEAD(&bss->cell_list); |
| 665 | bss->trans = trans; |
| 666 | bss->trans_type = trans->type; |
| 667 | bss->callref = trans->callref; |
| 668 | bss->pc = b->pc; |
| 669 | /* Create ran connection. */ |
| 670 | bss->conn = ran_conn_create_outgoing(rp); |
| 671 | if (!bss->conn) { |
Andreas Eversberg | cc7b7b8 | 2023-07-27 13:17:50 +0200 | [diff] [blame] | 672 | LOG_GCC(trans, LOGL_ERROR, "Failed to create RAN connection.\n"); |
Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 673 | osmo_fsm_inst_free(bss->fi); |
| 674 | continue; |
| 675 | } |
| 676 | bss->conn->vgcs.bss = bss; |
| 677 | /* Create cell list structures. */ |
| 678 | llist_for_each_entry(c, &b->cell_list, list) { |
Andreas Eversberg | cc7b7b8 | 2023-07-27 13:17:50 +0200 | [diff] [blame] | 679 | LOG_GCC(trans, LOGL_DEBUG, " -> Cell ID %d.\n", c->cell_id); |
Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 680 | /* Create state machine. */ |
| 681 | fi = osmo_fsm_inst_alloc(&vgcs_cell_fsm, net, NULL, LOGL_DEBUG, NULL); |
| 682 | if (!fi) { |
| 683 | LOG_GCC(trans, LOGL_ERROR, "No memory for state machine.\n"); |
| 684 | break; |
| 685 | } |
| 686 | /* Create cell structure. */ |
| 687 | cell = talloc_zero(fi, struct vgcs_bss_cell); |
| 688 | if (!cell) { |
| 689 | LOG_GCC(trans, LOGL_ERROR, "No memory for BSS cell structure.\n"); |
| 690 | osmo_fsm_inst_free(fi); |
| 691 | break; |
| 692 | } |
| 693 | cell->fi = fi; |
| 694 | fi->priv = cell; |
| 695 | osmo_fsm_inst_update_id_f(cell->fi, "vgcs-cell-%d", c->cell_id); |
| 696 | cell->trans_type = trans->type; |
| 697 | cell->callref = trans->callref; |
| 698 | cell->pc = b->pc; |
| 699 | cell->cell_id = c->cell_id; |
| 700 | cell->call_id = trans->call_id; |
| 701 | /* Create ran connection. */ |
| 702 | cell->conn = ran_conn_create_outgoing(rp); |
| 703 | if (!cell->conn) { |
Andreas Eversberg | cc7b7b8 | 2023-07-27 13:17:50 +0200 | [diff] [blame] | 704 | LOG_GCC(trans, LOGL_ERROR, "Failed to create RAN connection.\n"); |
Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 705 | osmo_fsm_inst_free(cell->fi); |
| 706 | continue; |
| 707 | } |
| 708 | cell->conn->vgcs.cell = cell; |
| 709 | /* Attach to cell list of BSS and MGW endpoint */ |
| 710 | llist_add_tail(&cell->list_bss, &bss->cell_list); |
| 711 | cell->bss = bss; |
| 712 | llist_add_tail(&cell->list_mgw, &mgw->cell_list); |
| 713 | cell->mgw = mgw; |
| 714 | } |
| 715 | /* No cell? */ |
| 716 | if (llist_empty(&bss->cell_list)) { |
Andreas Eversberg | cc7b7b8 | 2023-07-27 13:17:50 +0200 | [diff] [blame] | 717 | LOG_GCC(trans, LOGL_DEBUG, " -> No Cell in this BSS.\n"); |
Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 718 | osmo_fsm_inst_free(bss->fi); |
| 719 | break; |
| 720 | } |
| 721 | /* Attach to transaction list */ |
| 722 | llist_add_tail(&bss->list, &trans->gcc.bss_list); |
| 723 | /* Trigger VGCS/VBS SETUP */ |
| 724 | osmo_fsm_inst_dispatch(bss->fi, VGCS_BSS_EV_SETUP, NULL); |
| 725 | } |
| 726 | /* No BSS? */ |
| 727 | if (llist_empty(&trans->gcc.bss_list)) { |
| 728 | /* Also destroy MGW, because this list is empty too! */ |
Andreas Eversberg | cc7b7b8 | 2023-07-27 13:17:50 +0200 | [diff] [blame] | 729 | LOG_GCC(trans, LOGL_NOTICE, "No BSS found, please check your VTY configuration and add cells.\n"); |
Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 730 | goto err_mgw; |
| 731 | } |
| 732 | return 0; |
| 733 | |
| 734 | err_mgw: |
| 735 | if (mgw) { |
| 736 | if (mgw->mgw_ep) { |
| 737 | /* This will also free FSM instance and vgcs_mgw_ep structure. */ |
| 738 | osmo_fsm_inst_dispatch(mgw->fi, VGCS_MGW_EP_EV_CLEAR, NULL); |
| 739 | return -EINVAL; |
| 740 | } |
| 741 | osmo_fsm_inst_free(mgw->fi); |
| 742 | } |
| 743 | return -EINVAL; |
| 744 | } |
| 745 | |
| 746 | /* Send Assignment Request to the calling subscriber. |
| 747 | * This is used to assign the subscriber from early assigned channel to the VGCS/VBS channel. */ |
| 748 | static int gcc_assign(struct gsm_trans *trans) |
| 749 | { |
| 750 | struct ran_msg tx_ran_msg; |
| 751 | struct gsm0808_channel_type channel_type; |
| 752 | struct vgcs_bss *bss = NULL, *b; |
| 753 | |
| 754 | /* No assignment, because the calling subscriber is already assigned or there is no calling subscriber. */ |
| 755 | if (!trans->msc_a) |
| 756 | return 0; |
| 757 | |
| 758 | /* Check calling subscriber's MSC */ |
| 759 | struct ran_conn *conn = msub_ran_conn(trans->msc_a->c.msub); |
| 760 | if (!conn) { |
| 761 | LOG_GCC(trans, LOGL_ERROR, "Calling subscriber has no ran_conn????\n"); |
| 762 | return -EINVAL; |
| 763 | } |
| 764 | llist_for_each_entry(b, &trans->gcc.bss_list, list) { |
| 765 | if (osmo_sccp_addr_ri_cmp(&conn->ran_peer->peer_addr, &b->conn->ran_peer->peer_addr)) |
| 766 | continue; |
| 767 | bss = b; |
| 768 | break; |
| 769 | } |
| 770 | if (!bss) { |
| 771 | LOG_GCC(trans, LOGL_ERROR, "Calling subscriber comes from BSC that has no VGCS call.\n"); |
| 772 | return -EINVAL; |
| 773 | } |
| 774 | |
| 775 | /* For now we support GSM/FR V1 only. This shall be supported by all MS. */ |
| 776 | channel_type = (struct gsm0808_channel_type) { |
| 777 | .ch_indctr = GSM0808_CHAN_SPEECH, |
| 778 | .ch_rate_type = GSM0808_SPEECH_FULL_BM, |
| 779 | .perm_spch_len = 1, |
| 780 | .perm_spch[0] = GSM0808_PERM_FR1, |
| 781 | }; |
| 782 | |
| 783 | /* Send assignment to VGCS channel */ |
| 784 | tx_ran_msg = (struct ran_msg) { |
| 785 | .msg_type = RAN_MSG_ASSIGNMENT_COMMAND, |
| 786 | .assignment_command = { |
| 787 | .channel_type = &channel_type, |
| 788 | .callref_present = true, |
| 789 | .callref = { |
| 790 | .sf = (trans->type == TRANS_GCC), |
| 791 | }, |
| 792 | }, |
| 793 | }; |
| 794 | osmo_store32be_ext(trans->callref >> 3, &tx_ran_msg.assignment_command.callref.call_ref_hi, 3); |
| 795 | tx_ran_msg.assignment_command.callref.call_ref_lo = trans->callref & 0x7; |
| 796 | if (msc_a_ran_down(trans->msc_a, MSC_ROLE_I, &tx_ran_msg)) { |
| 797 | LOG_GCC(trans, LOGL_ERROR, "Cannot send Assignment\n"); |
| 798 | return -EIO; |
| 799 | } |
| 800 | |
| 801 | /* Assign Talker to BSS of the calling subscriber. */ |
| 802 | trans->gcc.uplink_bss = bss; |
| 803 | |
| 804 | return 0; |
| 805 | } |
| 806 | |
| 807 | /* Send CONNECT to the calling subscriber. */ |
| 808 | static void gcc_connect(struct gsm_trans *trans) |
| 809 | { |
| 810 | uint8_t pdisc = (trans->type == TRANS_GCC) ? GSM48_PDISC_GROUP_CC : GSM48_PDISC_BCAST_CC; |
| 811 | int rc; |
| 812 | |
| 813 | /* Send CONNECT towards MS. */ |
| 814 | rc = gsm44068_tx_connect(trans, |
| 815 | pdisc | (trans->transaction_id << 4), |
| 816 | trans->callref, 0, 0, 1, 0, 0, 0, 0); |
| 817 | if (rc < 0) |
| 818 | LOG_GCC(trans, LOGL_ERROR, "Failed to send CONNECT towards MS. Continue anyway.\n"); |
| 819 | } |
| 820 | |
| 821 | /* Release dedicated (SDCCH) channel of calling subscriber after assigning to VGCS */ |
| 822 | static void release_msc_a(struct gsm_trans *trans) |
| 823 | { |
| 824 | struct msc_a *msc_a = trans->msc_a; |
| 825 | |
| 826 | if (!msc_a) |
| 827 | return; |
| 828 | |
| 829 | trans->msc_a = NULL; |
| 830 | switch (trans->type) { |
| 831 | case TRANS_GCC: |
| 832 | msc_a_put(msc_a, MSC_A_USE_GCC); |
| 833 | break; |
| 834 | case TRANS_BCC: |
| 835 | msc_a_put(msc_a, MSC_A_USE_BCC); |
| 836 | break; |
| 837 | default: |
| 838 | break; |
| 839 | } |
| 840 | } |
| 841 | |
| 842 | /* Send TERMINATE to the calling/talking subscriber, then destroy transaction. */ |
| 843 | static void gcc_terminate_and_destroy(struct gsm_trans *trans, enum osmo_gsm44068_cause cause) |
| 844 | { |
| 845 | uint8_t pdisc = (trans->type == TRANS_GCC) ? GSM48_PDISC_GROUP_CC : GSM48_PDISC_BCAST_CC; |
| 846 | int rc; |
| 847 | |
| 848 | /* Send TERMINATION towards MS. */ |
| 849 | rc = gsm44068_tx_termination(trans->msc_a, trans->gcc.uplink_bss, |
| 850 | pdisc | (trans->transaction_id << 4), |
| 851 | OSMO_GSM44068_MSGT_TERMINATION, |
| 852 | cause, NULL, 0); |
| 853 | if (rc < 0) |
| 854 | LOG_GCC(trans, LOGL_ERROR, "Failed to send TERMINATION towards MS. Continue anyway.\n"); |
| 855 | |
| 856 | /* Destroy transaction, note that also _gsm44068_gcc_trans_free() will be called by trans_free(). |
| 857 | * There the complete state machine is destroyed. */ |
| 858 | trans->callref = 0; |
| 859 | trans_free(trans); |
| 860 | } |
| 861 | |
Andreas Eversberg | 1d3e48f | 2023-08-21 15:54:51 +0200 | [diff] [blame] | 862 | /* Send TERMINATION REJECT to the calling/talking subscriber. */ |
| 863 | static void gcc_termination_reject(struct gsm_trans *trans, enum osmo_gsm44068_cause cause) |
| 864 | { |
| 865 | uint8_t pdisc = (trans->type == TRANS_GCC) ? GSM48_PDISC_GROUP_CC : GSM48_PDISC_BCAST_CC; |
| 866 | int rc; |
| 867 | |
| 868 | /* Send TERMINATION towards MS. */ |
| 869 | rc = gsm44068_tx_termination(trans->msc_a, trans->gcc.uplink_bss, |
| 870 | pdisc | (trans->transaction_id << 4), |
| 871 | OSMO_GSM44068_MSGT_TERMINATION_REJECT, |
| 872 | cause, NULL, 0); |
| 873 | if (rc < 0) |
| 874 | LOG_GCC(trans, LOGL_ERROR, "Failed to send TERMINATION REJECT towards MS.\n"); |
| 875 | } |
| 876 | |
Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 877 | /* Start inactivity timer. |
| 878 | * This timer is used to terminate the call, if the radio connection to the caller gets lost. */ |
| 879 | static void start_inactivity_timer(struct gsm_trans *trans) |
| 880 | { |
| 881 | if (trans->gcc.inactivity_to) { |
| 882 | LOG_GCC(trans, LOGL_DEBUG, "Set inactivity timer to %d seconds.\n", trans->gcc.inactivity_to); |
| 883 | osmo_timer_schedule(&trans->gcc.timer_inactivity, trans->gcc.inactivity_to, 0); |
| 884 | } |
| 885 | } |
| 886 | |
| 887 | static void stop_inactivity_timer(struct gsm_trans *trans) |
| 888 | { |
| 889 | if (osmo_timer_pending(&trans->gcc.timer_inactivity)) { |
| 890 | LOG_GCC(trans, LOGL_DEBUG, "Stop pending inactivity timer.\n"); |
| 891 | osmo_timer_del(&trans->gcc.timer_inactivity); |
| 892 | } |
| 893 | } |
| 894 | |
| 895 | static void inactivity_timer_cb(void *data) |
| 896 | { |
| 897 | struct gsm_trans *trans = data; |
| 898 | |
| 899 | osmo_fsm_inst_dispatch(trans->gcc.fi, VGCS_GCC_EV_TIMEOUT, NULL); |
| 900 | } |
| 901 | |
| 902 | /* Set the parameters of the talker. (downlink mute/unmute, uplink unmute, COMM=T, originator) */ |
| 903 | static int set_parameter(struct gsm_trans *trans) |
| 904 | { |
| 905 | uint8_t pdisc = (trans->type == TRANS_GCC) ? GSM48_PDISC_GROUP_CC : GSM48_PDISC_BCAST_CC; |
| 906 | int rc; |
| 907 | |
Andreas Eversberg | 1c98031 | 2023-07-27 13:18:27 +0200 | [diff] [blame] | 908 | rc = gsm44068_tx_set_parameter(trans, pdisc | (trans->transaction_id << 4), |
| 909 | !trans->gcc.mute_talker, 1, 1, trans->gcc.uplink_originator); |
Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 910 | if (rc < 0) |
| 911 | LOG_GCC(trans, LOGL_ERROR, "Failed to send SET PARAMETER towards MS.\n"); |
| 912 | return rc; |
| 913 | } |
| 914 | |
| 915 | /* Check in which cell the uplink is used and set "uplink_cell". */ |
| 916 | static int set_uplink_cell(struct vgcs_bss *bss, struct gsm0808_cell_id *cell_id_ie, uint16_t cell_id) |
| 917 | { |
| 918 | struct vgcs_bss_cell *cell; |
| 919 | |
| 920 | if (cell_id_ie) { |
| 921 | /* Get cell ID to determine talker channel. */ |
| 922 | switch (cell_id_ie->id_discr) { |
| 923 | case CELL_IDENT_CI: |
| 924 | cell_id = cell_id_ie->id.ci; |
| 925 | break; |
| 926 | case CELL_IDENT_LAC_AND_CI: |
| 927 | cell_id = cell_id_ie->id.lac_and_ci.ci; |
| 928 | break; |
| 929 | default: |
| 930 | LOG_BSS(bss, LOGL_DEBUG, "Cannot idenitfy cell, please fix!\n"); |
| 931 | return -EINVAL; |
| 932 | } |
| 933 | } |
| 934 | |
| 935 | /* Search for cell ID. */ |
| 936 | bss->trans->gcc.uplink_cell = NULL; |
| 937 | llist_for_each_entry(cell, &bss->cell_list, list_bss) { |
| 938 | if (cell->cell_id == cell_id) { |
| 939 | LOG_BSS(bss, LOGL_DEBUG, "Talker is talking on cell %d.\n", cell->cell_id); |
| 940 | bss->trans->gcc.uplink_cell = cell; |
| 941 | return 0; |
| 942 | } |
| 943 | } |
| 944 | |
| 945 | LOG_BSS(bss, LOGL_DEBUG, "Cell ID %d is not in list of current BSS, please fix!\n", cell_id); |
| 946 | return -EINVAL; |
| 947 | } |
| 948 | |
| 949 | /* Set the MGW conference mode. |
| 950 | * All cells are listening to the conference. If there is a talker, this cell is also transmitting to the conference. */ |
| 951 | static int set_mgw_conference(struct gsm_trans *trans) |
| 952 | { |
| 953 | struct vgcs_bss *bss; |
| 954 | struct vgcs_bss_cell *cell; |
| 955 | struct rtp_stream *rtps; |
| 956 | int rc; |
| 957 | |
| 958 | /* All cells without talker are listening */ |
| 959 | llist_for_each_entry(bss, &trans->gcc.bss_list, list) { |
| 960 | llist_for_each_entry(cell, &bss->cell_list, list_bss) { |
| 961 | if (!(rtps = cell->rtps)) |
| 962 | continue; |
| 963 | if (rtps->crcx_conn_mode != MGCP_CONN_SEND_ONLY) { |
| 964 | LOG_CELL(cell, LOGL_DEBUG, "Setting cell %d into listening mode.\n", cell->cell_id); |
| 965 | rtp_stream_set_mode(rtps, MGCP_CONN_SEND_ONLY); |
| 966 | rc = rtp_stream_commit(rtps); |
| 967 | if (rc < 0) |
| 968 | LOG_CELL(cell, LOGL_ERROR, "Failed to commit parameters to RTP stream " |
| 969 | "for cell %d.\n", cell->cell_id); |
| 970 | } |
| 971 | } |
| 972 | } |
| 973 | |
| 974 | if (trans->gcc.uplink_cell && trans->gcc.uplink_cell->rtps) { |
| 975 | cell = trans->gcc.uplink_cell; |
| 976 | rtps = cell->rtps; |
| 977 | LOG_CELL(cell, LOGL_DEBUG, "Setting cell %d into listening mode.\n", cell->cell_id); |
| 978 | rtp_stream_set_mode(rtps, MGCP_CONN_CONFECHO); |
| 979 | rc = rtp_stream_commit(rtps); |
| 980 | if (rc < 0) |
| 981 | LOG_CELL(cell, LOGL_ERROR, "Failed to commit parameters to RTP stream " |
| 982 | "for cell %d.\n", cell->cell_id); |
| 983 | } |
| 984 | |
| 985 | return 0; |
| 986 | } |
| 987 | |
| 988 | static void _assign_complete(struct gsm_trans *trans, bool send_connect) |
| 989 | { |
| 990 | uint16_t cell_id; |
| 991 | |
Andreas Eversberg | e2a4088 | 2023-07-19 09:56:53 +0200 | [diff] [blame] | 992 | OSMO_ASSERT(trans->msc_a); |
| 993 | |
Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 994 | /* Change state. */ |
| 995 | osmo_fsm_inst_state_chg(trans->gcc.fi, VGCS_GCC_ST_N2_CALL_ACTIVE, 0, 0); |
| 996 | /* Get cell ID. */ |
Andreas Eversberg | e2a4088 | 2023-07-19 09:56:53 +0200 | [diff] [blame] | 997 | cell_id = trans->msc_a->via_cell.cell_identity; |
Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 998 | /* Releasing dedicated channel. */ |
| 999 | release_msc_a(trans); |
| 1000 | /* Send CONNECT to the calling subscriber. */ |
| 1001 | if (send_connect) |
| 1002 | gcc_connect(trans); |
| 1003 | /* Set parameter. */ |
| 1004 | set_parameter(trans); |
| 1005 | /* Start inactivity timer, if uplink is free. */ |
| 1006 | if (!trans->gcc.uplink_busy) |
| 1007 | start_inactivity_timer(trans); |
| 1008 | /* Set cell of current talker. */ |
| 1009 | set_uplink_cell(trans->gcc.uplink_bss, NULL, cell_id); |
| 1010 | /* Set MGW conference. */ |
| 1011 | set_mgw_conference(trans); |
| 1012 | } |
| 1013 | |
| 1014 | #define CONNECT_OPTION false |
| 1015 | |
| 1016 | static void vgcs_gcc_fsm_n0_null(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 1017 | { |
| 1018 | struct gsm_trans *trans = fi->priv; |
| 1019 | int rc; |
| 1020 | |
| 1021 | switch (event) { |
| 1022 | case VGCS_GCC_EV_NET_SETUP: |
| 1023 | /* Establish call towards all BSSs. */ |
| 1024 | LOG_GCC(trans, LOGL_DEBUG, "Setup by network, trying to establish cells.\n"); |
| 1025 | rc = gcc_establish_bss(trans); |
| 1026 | if (rc < 0) { |
| 1027 | LOG_GCC(trans, LOGL_NOTICE, "Failed to setup call to any cell.\n"); |
| 1028 | gcc_terminate_and_destroy(trans, OSMO_GSM44068_CAUSE_NETWORK_FAILURE); |
| 1029 | break; |
| 1030 | } |
| 1031 | /* Keep state until established or released. */ |
| 1032 | break; |
| 1033 | case VGCS_GCC_EV_NET_TERM: |
| 1034 | LOG_GCC(trans, LOGL_DEBUG, "Termination by network, destroying call.\n"); |
| 1035 | /* Destroy group call in all cells. */ |
| 1036 | gcc_terminate_and_destroy(trans, OSMO_GSM44068_CAUSE_NORMAL_CALL_CLEARING); |
| 1037 | break; |
| 1038 | case VGCS_GCC_EV_USER_SETUP: |
| 1039 | LOG_GCC(trans, LOGL_DEBUG, "Setup by MS, trying to establish cells.\n"); |
| 1040 | /* Change state. */ |
| 1041 | osmo_fsm_inst_state_chg(fi, VGCS_GCC_ST_N1_CALL_INITIATED, 0, 0); |
| 1042 | /* Establish call towards all BSSs. */ |
| 1043 | rc = gcc_establish_bss(trans); |
| 1044 | if (rc < 0) { |
| 1045 | LOG_GCC(trans, LOGL_NOTICE, "Failed to setup call to any cell.\n"); |
| 1046 | gcc_terminate_and_destroy(trans, OSMO_GSM44068_CAUSE_NETWORK_FAILURE); |
| 1047 | break; |
| 1048 | } |
| 1049 | if (CONNECT_OPTION) { |
| 1050 | /* Send CONNECT to the calling subscriber. */ |
| 1051 | gcc_connect(trans); |
| 1052 | /* Change state. */ |
| 1053 | osmo_fsm_inst_state_chg(fi, VGCS_GCC_ST_N3_CALL_EST_PROC, 0, 0); |
| 1054 | } |
| 1055 | break; |
| 1056 | case VGCS_GCC_EV_BSS_ESTABLISHED: |
| 1057 | LOG_GCC(trans, LOGL_DEBUG, "All cells establised, for a group call, sending CONNECT to caller.\n"); |
| 1058 | /* Change state. */ |
| 1059 | osmo_fsm_inst_state_chg(fi, VGCS_GCC_ST_N2_CALL_ACTIVE, 0, 0); |
| 1060 | /* Start inactivity timer, if uplink is free. */ |
| 1061 | if (!trans->gcc.uplink_busy) |
| 1062 | start_inactivity_timer(trans); |
| 1063 | break; |
| 1064 | case VGCS_GCC_EV_BSS_RELEASED: |
| 1065 | LOG_GCC(trans, LOGL_DEBUG, "All group call in all cells failed, destroying call.\n"); |
| 1066 | /* Send TERMINATE to the calling subscriber. */ |
| 1067 | gcc_terminate_and_destroy(trans, OSMO_GSM44068_CAUSE_NETWORK_FAILURE); |
| 1068 | break; |
| 1069 | default: |
| 1070 | OSMO_ASSERT(false); |
| 1071 | } |
| 1072 | } |
| 1073 | |
| 1074 | static void vgcs_gcc_fsm_n1_call_initiated(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 1075 | { |
| 1076 | struct gsm_trans *trans = fi->priv; |
| 1077 | int rc; |
| 1078 | |
| 1079 | switch (event) { |
| 1080 | case VGCS_GCC_EV_NET_TERM: |
| 1081 | LOG_GCC(trans, LOGL_DEBUG, "Termination by network, destroying call.\n"); |
| 1082 | /* Destroy group call in all cells. */ |
| 1083 | gcc_terminate_and_destroy(trans, OSMO_GSM44068_CAUSE_NORMAL_CALL_CLEARING); |
| 1084 | break; |
| 1085 | case VGCS_GCC_EV_USER_TERM: |
| 1086 | LOG_GCC(trans, LOGL_DEBUG, "Termination by user, destroying call.\n"); |
| 1087 | /* Send TERMINATE to the calling subscriber and destroy group call in all cells. */ |
| 1088 | gcc_terminate_and_destroy(trans, OSMO_GSM44068_CAUSE_NORMAL_CALL_CLEARING); |
| 1089 | break; |
| 1090 | case VGCS_GCC_EV_BSS_ESTABLISHED: |
| 1091 | LOG_GCC(trans, LOGL_DEBUG, "All cells establised, for a group call, assign caller to VGCS.\n"); |
| 1092 | /* Send assignment to the calling subscriber. */ |
| 1093 | rc = gcc_assign(trans); |
| 1094 | if (rc < 0) { |
| 1095 | gcc_terminate_and_destroy(trans, OSMO_GSM44068_CAUSE_NETWORK_FAILURE); |
| 1096 | break; |
| 1097 | } |
| 1098 | break; |
| 1099 | case VGCS_GCC_EV_BSS_ASSIGN_CPL: |
| 1100 | LOG_GCC(trans, LOGL_DEBUG, "Assignment complete, sending CONNECT to caller, releasing channel.\n"); |
| 1101 | /* Handle assignment complete */ |
| 1102 | _assign_complete(trans, true); |
| 1103 | break; |
| 1104 | case VGCS_GCC_EV_BSS_ASSIGN_FAIL: |
| 1105 | LOG_GCC(trans, LOGL_DEBUG, "Assignment failed, releasing call.\n"); |
| 1106 | /* Send TERMINATE to the calling subscriber. */ |
| 1107 | gcc_terminate_and_destroy(trans, OSMO_GSM44068_CAUSE_NETWORK_FAILURE); |
| 1108 | break; |
| 1109 | case VGCS_GCC_EV_BSS_RELEASED: |
| 1110 | LOG_GCC(trans, LOGL_DEBUG, "All group call in all cells failed, destroying call.\n"); |
| 1111 | /* Send TERMINATE to the calling subscriber. */ |
| 1112 | gcc_terminate_and_destroy(trans, OSMO_GSM44068_CAUSE_NETWORK_FAILURE); |
| 1113 | break; |
| 1114 | default: |
| 1115 | OSMO_ASSERT(false); |
| 1116 | } |
| 1117 | } |
| 1118 | |
| 1119 | static void vgcs_gcc_fsm_n2_call_active(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 1120 | { |
| 1121 | struct gsm_trans *trans = fi->priv; |
| 1122 | |
| 1123 | switch (event) { |
| 1124 | case VGCS_GCC_EV_NET_TERM: |
| 1125 | LOG_GCC(trans, LOGL_DEBUG, "Termination by network, destroying call.\n"); |
| 1126 | /* Destroy group call in all cells. */ |
| 1127 | gcc_terminate_and_destroy(trans, OSMO_GSM44068_CAUSE_NORMAL_CALL_CLEARING); |
| 1128 | break; |
| 1129 | case VGCS_GCC_EV_USER_TERM: |
Andreas Eversberg | 1d3e48f | 2023-08-21 15:54:51 +0200 | [diff] [blame] | 1130 | if (!trans->gcc.uplink_originator) { |
| 1131 | LOG_GCC(trans, LOGL_ERROR, "Termination by user, but it is not the originator.\n"); |
| 1132 | gcc_termination_reject(trans, OSMO_GSM44068_CAUSE_USER_NOT_ORIGINATOR); |
| 1133 | break; |
| 1134 | } |
Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 1135 | LOG_GCC(trans, LOGL_DEBUG, "Termination by user, destroying call.\n"); |
| 1136 | /* Send TERMINATE to the calling subscriber and destroy group call in all cells. */ |
| 1137 | gcc_terminate_and_destroy(trans, OSMO_GSM44068_CAUSE_NORMAL_CALL_CLEARING); |
| 1138 | break; |
| 1139 | case VGCS_GCC_EV_BSS_RELEASED: |
| 1140 | LOG_GCC(trans, LOGL_DEBUG, "All group call in all cells failed, destroying call.\n"); |
| 1141 | /* Send TERMINATE to the calling subscriber. */ |
| 1142 | gcc_terminate_and_destroy(trans, OSMO_GSM44068_CAUSE_NETWORK_FAILURE); |
| 1143 | break; |
| 1144 | case VGCS_GCC_EV_TIMEOUT: |
| 1145 | LOG_GCC(trans, LOGL_DEBUG, "Termination by inactivity timer, destroying call.\n"); |
| 1146 | /* Destroy group call in all cells. */ |
| 1147 | gcc_terminate_and_destroy(trans, OSMO_GSM44068_CAUSE_NORMAL_CALL_CLEARING); |
| 1148 | break; |
| 1149 | default: |
| 1150 | OSMO_ASSERT(false); |
| 1151 | } |
| 1152 | } |
| 1153 | |
| 1154 | static void vgcs_gcc_fsm_n3_call_est_proc(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 1155 | { |
| 1156 | struct gsm_trans *trans = fi->priv; |
| 1157 | int rc; |
| 1158 | |
| 1159 | switch (event) { |
| 1160 | case VGCS_GCC_EV_NET_TERM: |
| 1161 | LOG_GCC(trans, LOGL_DEBUG, "Termination by network, destroying call.\n"); |
| 1162 | /* Destroy group call in all cells. */ |
| 1163 | gcc_terminate_and_destroy(trans, OSMO_GSM44068_CAUSE_NORMAL_CALL_CLEARING); |
| 1164 | break; |
| 1165 | case VGCS_GCC_EV_USER_TERM: |
| 1166 | LOG_GCC(trans, LOGL_DEBUG, "Termination by user, destroying call.\n"); |
| 1167 | /* Send TERMINATE to the calling subscriber and destroy group call in all cells. */ |
| 1168 | gcc_terminate_and_destroy(trans, OSMO_GSM44068_CAUSE_NORMAL_CALL_CLEARING); |
| 1169 | break; |
| 1170 | case VGCS_GCC_EV_BSS_ESTABLISHED: |
| 1171 | LOG_GCC(trans, LOGL_DEBUG, "All cells establised, for a group call, assign caller to VGCS.\n"); |
| 1172 | /* Send assignment to the calling subscriber. */ |
| 1173 | rc = gcc_assign(trans); |
| 1174 | if (rc < 0) { |
| 1175 | gcc_terminate_and_destroy(trans, OSMO_GSM44068_CAUSE_NETWORK_FAILURE); |
| 1176 | break; |
| 1177 | } |
| 1178 | break; |
| 1179 | case VGCS_GCC_EV_BSS_ASSIGN_CPL: |
| 1180 | LOG_GCC(trans, LOGL_DEBUG, "Assignment complete, sending CONNECT to caller, releasing channel.\n"); |
| 1181 | /* Handle assignment complete */ |
| 1182 | _assign_complete(trans, false); |
| 1183 | break; |
| 1184 | case VGCS_GCC_EV_BSS_ASSIGN_FAIL: |
| 1185 | LOG_GCC(trans, LOGL_DEBUG, "Assignment failed, releasing call.\n"); |
| 1186 | /* Send TERMINATE to the calling subscriber. */ |
| 1187 | gcc_terminate_and_destroy(trans, OSMO_GSM44068_CAUSE_NETWORK_FAILURE); |
| 1188 | break; |
| 1189 | case VGCS_GCC_EV_BSS_RELEASED: |
| 1190 | LOG_GCC(trans, LOGL_DEBUG, "All group call in all cells failed, destroying call.\n"); |
| 1191 | /* Send TERMINATE to the calling subscriber. */ |
| 1192 | gcc_terminate_and_destroy(trans, OSMO_GSM44068_CAUSE_NETWORK_FAILURE); |
| 1193 | break; |
| 1194 | default: |
| 1195 | OSMO_ASSERT(false); |
| 1196 | } |
| 1197 | } |
| 1198 | |
| 1199 | static const struct osmo_fsm_state vgcs_gcc_fsm_states[] = { |
| 1200 | [VGCS_GCC_ST_N0_NULL] = { |
| 1201 | .name = "NULL (N0)", |
| 1202 | .in_event_mask = S(VGCS_GCC_EV_NET_SETUP) | |
| 1203 | S(VGCS_GCC_EV_NET_TERM) | |
| 1204 | S(VGCS_GCC_EV_USER_SETUP) | |
| 1205 | S(VGCS_GCC_EV_BSS_ESTABLISHED) | |
| 1206 | S(VGCS_GCC_EV_BSS_RELEASED), |
| 1207 | .out_state_mask = S(VGCS_GCC_ST_N1_CALL_INITIATED) | |
| 1208 | S(VGCS_GCC_ST_N2_CALL_ACTIVE), |
| 1209 | .action = vgcs_gcc_fsm_n0_null, |
| 1210 | }, |
| 1211 | [VGCS_GCC_ST_N1_CALL_INITIATED] = { |
| 1212 | .name = "CALL INITATED (N1)", |
| 1213 | .in_event_mask = S(VGCS_GCC_EV_NET_TERM) | |
| 1214 | S(VGCS_GCC_EV_USER_TERM) | |
| 1215 | S(VGCS_GCC_EV_BSS_ESTABLISHED) | |
| 1216 | S(VGCS_GCC_EV_BSS_ASSIGN_CPL) | |
| 1217 | S(VGCS_GCC_EV_BSS_ASSIGN_FAIL) | |
| 1218 | S(VGCS_GCC_EV_BSS_RELEASED), |
| 1219 | .out_state_mask = S(VGCS_GCC_ST_N0_NULL) | |
| 1220 | S(VGCS_GCC_ST_N2_CALL_ACTIVE) | |
| 1221 | S(VGCS_GCC_ST_N3_CALL_EST_PROC), |
| 1222 | .action = vgcs_gcc_fsm_n1_call_initiated, |
| 1223 | }, |
| 1224 | [VGCS_GCC_ST_N2_CALL_ACTIVE] = { |
| 1225 | .name = "CALL ACTIVE (N2)", |
| 1226 | .in_event_mask = S(VGCS_GCC_EV_NET_TERM) | |
| 1227 | S(VGCS_GCC_EV_USER_TERM) | |
| 1228 | S(VGCS_GCC_EV_BSS_RELEASED) | |
| 1229 | S(VGCS_GCC_EV_TIMEOUT), |
| 1230 | .out_state_mask = S(VGCS_GCC_ST_N0_NULL), |
| 1231 | .action = vgcs_gcc_fsm_n2_call_active, |
| 1232 | }, |
| 1233 | [VGCS_GCC_ST_N3_CALL_EST_PROC] = { |
| 1234 | .name = "CALL EST PROCEEDING (N3)", |
| 1235 | .in_event_mask = S(VGCS_GCC_EV_NET_TERM) | |
| 1236 | S(VGCS_GCC_EV_USER_TERM) | |
| 1237 | S(VGCS_GCC_EV_BSS_ESTABLISHED) | |
| 1238 | S(VGCS_GCC_EV_BSS_ASSIGN_CPL) | |
| 1239 | S(VGCS_GCC_EV_BSS_ASSIGN_FAIL) | |
| 1240 | S(VGCS_GCC_EV_BSS_RELEASED), |
| 1241 | .out_state_mask = S(VGCS_GCC_ST_N2_CALL_ACTIVE) | |
| 1242 | S(VGCS_GCC_ST_N0_NULL), |
| 1243 | .action = vgcs_gcc_fsm_n3_call_est_proc, |
| 1244 | }, |
| 1245 | // We don't need a state to wait for the group call to be terminated in all cells |
| 1246 | }; |
| 1247 | |
| 1248 | static struct osmo_fsm vgcs_bcc_fsm = { |
| 1249 | .name = "bcc", |
| 1250 | .states = vgcs_gcc_fsm_states, |
| 1251 | .num_states = ARRAY_SIZE(vgcs_gcc_fsm_states), |
| 1252 | .log_subsys = DBCC, |
| 1253 | .event_names = vgcs_gcc_fsm_event_names, |
| 1254 | }; |
| 1255 | |
| 1256 | static struct osmo_fsm vgcs_gcc_fsm = { |
| 1257 | .name = "gcc", |
| 1258 | .states = vgcs_gcc_fsm_states, |
| 1259 | .num_states = ARRAY_SIZE(vgcs_gcc_fsm_states), |
| 1260 | .log_subsys = DGCC, |
| 1261 | .event_names = vgcs_gcc_fsm_event_names, |
| 1262 | }; |
| 1263 | |
| 1264 | const char *vgcs_bcc_gcc_state_name(struct osmo_fsm_inst *fi) |
| 1265 | { |
| 1266 | return vgcs_gcc_fsm_states[fi->state].name; |
| 1267 | } |
| 1268 | |
| 1269 | static int update_uplink_state(struct vgcs_bss *bss, bool uplink_busy); |
| 1270 | |
| 1271 | /* Receive RR messages from calling subscriber, prior assignment to VGCS/VBS. */ |
| 1272 | int gsm44068_rcv_rr(struct msc_a *msc_a, struct msgb *msg) |
| 1273 | { |
| 1274 | struct gsm_trans *trans = NULL; |
| 1275 | struct gsm48_hdr *gh; |
| 1276 | uint8_t msg_type; |
| 1277 | |
| 1278 | gh = msgb_l3(msg); |
| 1279 | msg_type = gsm48_hdr_msg_type(gh); |
| 1280 | |
| 1281 | /* Find transaction. */ |
| 1282 | trans = trans_find_by_type(msc_a, TRANS_GCC); |
| 1283 | if (!trans) |
| 1284 | trans = trans_find_by_type(msc_a, TRANS_BCC); |
| 1285 | |
| 1286 | if (!trans) { |
| 1287 | LOG_GCC(trans, LOGL_ERROR, "No VGCS/VBS transaction.\n"); |
| 1288 | return -EINVAL; |
| 1289 | } |
| 1290 | |
| 1291 | /* In case the phone releases uplink prior being assigned to a VGCS */ |
| 1292 | if (msg_type == GSM48_MT_RR_UPLINK_RELEASE) { |
| 1293 | struct vgcs_bss *bss; |
| 1294 | |
| 1295 | LOG_GCC(trans, LOGL_INFO, "Received UPLINK RELEASE on initial channel.\n"); |
| 1296 | /* Clear the busy flag and unblock all cells. */ |
| 1297 | trans->gcc.uplink_bss = NULL; |
| 1298 | trans->gcc.uplink_cell = NULL; |
| 1299 | trans->gcc.uplink_busy = false; |
| 1300 | llist_for_each_entry(bss, &trans->gcc.bss_list, list) { |
| 1301 | /* Update uplink state. */ |
| 1302 | update_uplink_state(bss, trans->gcc.uplink_busy); |
| 1303 | } |
| 1304 | /* Start inactivity timer. */ |
| 1305 | start_inactivity_timer(bss->trans); |
| 1306 | /* Next, the MS will switch to the VGCS as listener. Nothing else to do here. */ |
| 1307 | } |
| 1308 | |
| 1309 | return 0; |
| 1310 | } |
| 1311 | |
| 1312 | /* Allocation of transaction for group call */ |
| 1313 | static struct gsm_trans *trans_alloc_vgcs(struct gsm_network *net, |
| 1314 | struct vlr_subscr *vsub, |
| 1315 | enum trans_type trans_type, uint8_t transaction_id, |
| 1316 | uint32_t callref, |
| 1317 | struct gcr *gcr, |
| 1318 | bool uplink_busy) |
| 1319 | { |
| 1320 | struct gsm_trans *trans; |
| 1321 | |
| 1322 | trans = trans_alloc(net, vsub, trans_type, transaction_id, callref); |
| 1323 | if (!trans) { |
| 1324 | LOG_GCC(trans, LOGL_ERROR, "No memory for trans.\n"); |
| 1325 | return NULL; |
| 1326 | } |
| 1327 | /* The uplink is busy when the call is started until the calling subscriber releases. */ |
| 1328 | trans->gcc.uplink_busy = uplink_busy; |
| 1329 | trans->gcc.uplink_originator = true; |
| 1330 | INIT_LLIST_HEAD(&trans->gcc.bss_list); |
| 1331 | trans->gcc.inactivity_to = gcr->timeout; |
| 1332 | trans->gcc.mute_talker = gcr->mute_talker; |
| 1333 | trans->gcc.timer_inactivity.data = trans; |
| 1334 | trans->gcc.timer_inactivity.cb = inactivity_timer_cb; |
| 1335 | trans->gcc.fi = osmo_fsm_inst_alloc((trans_type == TRANS_GCC) ? &vgcs_gcc_fsm : &vgcs_bcc_fsm, |
| 1336 | trans, trans, LOGL_DEBUG, NULL); |
| 1337 | if (!trans->gcc.fi) { |
| 1338 | LOG_GCC(trans, LOGL_ERROR, "No memory for state machine.\n"); |
| 1339 | trans_free(trans); |
| 1340 | return NULL; |
| 1341 | } |
| 1342 | |
| 1343 | return trans; |
| 1344 | } |
| 1345 | |
| 1346 | /* Create transaction from incoming voice group/broadcast call. */ |
| 1347 | static struct gsm_trans *trans_create_bcc_gcc(struct msc_a *msc_a, enum trans_type trans_type, uint8_t transaction_id, |
| 1348 | uint8_t pdisc, uint8_t msg_type, uint32_t callref) |
| 1349 | { |
Andreas Eversberg | 7e65ed9 | 2023-07-19 09:38:25 +0200 | [diff] [blame] | 1350 | struct gsm_network *net; |
| 1351 | struct vlr_subscr *vsub; |
Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 1352 | struct gsm_trans *trans = NULL; |
| 1353 | struct gcr *gcr; |
| 1354 | int rc; |
| 1355 | |
| 1356 | if (!msc_a) { |
| 1357 | LOG_GCC(trans, LOGL_ERROR, "Invalid conn: no msc_a\n"); |
| 1358 | return NULL; |
| 1359 | } |
Andreas Eversberg | 7e65ed9 | 2023-07-19 09:38:25 +0200 | [diff] [blame] | 1360 | net = msc_a_net(msc_a); |
| 1361 | vsub = msc_a_vsub(msc_a); |
| 1362 | |
Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 1363 | if (!vsub) { |
| 1364 | LOG_GCC(trans, LOGL_ERROR, "Invalid conn: no subscriber\n"); |
| 1365 | return NULL; |
| 1366 | } |
| 1367 | |
| 1368 | /* An earlier CM Service Request for this CC message now has concluded */ |
| 1369 | if (!osmo_use_count_by(&msc_a->use_count, |
| 1370 | (trans_type == TRANS_GCC) ? MSC_A_USE_CM_SERVICE_GCC : MSC_A_USE_CM_SERVICE_BCC)) |
| 1371 | LOG_MSC_A(msc_a, LOGL_ERROR, |
| 1372 | "Creating new %s transaction without prior CM Service Request.\n", |
| 1373 | get_value_string(trans_type_names, trans_type)); |
| 1374 | else |
| 1375 | msc_a_put(msc_a, |
| 1376 | (trans_type == TRANS_GCC) ? MSC_A_USE_CM_SERVICE_GCC : MSC_A_USE_CM_SERVICE_BCC); |
| 1377 | |
| 1378 | /* A transaction must be created with a SETUP message. */ |
| 1379 | if (msg_type != OSMO_GSM44068_MSGT_IMMEDIATE_SETUP |
| 1380 | && msg_type != OSMO_GSM44068_MSGT_SETUP |
| 1381 | && msg_type != OSMO_GSM44068_MSGT_IMMEDIATE_SETUP_2) { |
| 1382 | LOG_GCC(trans, LOGL_ERROR, "No transaction and message is not a SETUP.\n"); |
| 1383 | return NULL; |
| 1384 | } |
| 1385 | |
| 1386 | /* Check if callref already exists. */ |
| 1387 | trans = trans_find_by_callref(net, trans_type, callref); |
| 1388 | if (trans) { |
| 1389 | LOG_GCC(trans, LOGL_INFO, "Call to existing %s with callref %s, rejecting!\n", |
| 1390 | trans_type_name(trans_type), gsm44068_group_id_string(callref)); |
| 1391 | rc = gsm44068_tx_termination(msc_a, NULL, |
| 1392 | pdisc | (transaction_id << 4), |
| 1393 | OSMO_GSM44068_MSGT_TERMINATION, |
| 1394 | OSMO_GSM44068_CAUSE_BUSY, NULL, 0); |
| 1395 | if (rc < 0) |
| 1396 | LOG_GCC(trans, LOGL_ERROR, "Failed to send TERMINATION towards MS.\n"); |
| 1397 | return 0; |
| 1398 | } |
| 1399 | |
| 1400 | /* Check GCR for Group ID. */ |
| 1401 | gcr = gcr_by_callref(net, trans_type, callref); |
| 1402 | if (!gcr) { |
| 1403 | LOG_GCC(trans, LOGL_INFO, "No Group configured for %s callref %s, rejecting!\n", |
| 1404 | trans_type_name(trans_type), gsm44068_group_id_string(callref)); |
| 1405 | // FIXME: Better cause value for a group that does not exist ? |
| 1406 | rc = gsm44068_tx_termination(msc_a, NULL, |
| 1407 | pdisc | (transaction_id << 4), |
| 1408 | OSMO_GSM44068_MSGT_TERMINATION, |
| 1409 | OSMO_GSM44068_CAUSE_REQUESTED_SERVICE_NOT_SUB, NULL, 0); |
| 1410 | if (rc < 0) |
| 1411 | LOG_GCC(trans, LOGL_ERROR, "Failed to send TERMINATION towards MS.\n"); |
| 1412 | return 0; |
| 1413 | } |
| 1414 | |
| 1415 | /* Create transaction, uplink is busy. */ |
| 1416 | trans = trans_alloc_vgcs(net, vsub, trans_type, transaction_id, callref, gcr, true); |
| 1417 | if (!trans) { |
| 1418 | rc = gsm44068_tx_termination(msc_a, NULL, |
| 1419 | pdisc | (transaction_id << 4), |
| 1420 | OSMO_GSM44068_MSGT_TERMINATION, |
| 1421 | OSMO_GSM44068_CAUSE_NETWORK_FAILURE, NULL, 0); |
| 1422 | if (rc < 0) |
| 1423 | LOG_GCC(trans, LOGL_ERROR, "Failed to send TERMINATION towards MS.\n"); |
| 1424 | return NULL; |
| 1425 | } |
| 1426 | |
| 1427 | if (osmo_fsm_inst_dispatch(msc_a->c.fi, MSC_A_EV_TRANSACTION_ACCEPTED, trans)) { |
| 1428 | LOG_MSC_A(msc_a, LOGL_ERROR, "Not allowed to accept %s transaction.\n", |
| 1429 | get_value_string(trans_type_names, trans_type)); |
| 1430 | gcc_terminate_and_destroy(trans, OSMO_GSM44068_CAUSE_NETWORK_FAILURE); |
| 1431 | return NULL; |
| 1432 | } |
| 1433 | |
| 1434 | /* Assign transaction */ |
| 1435 | msc_a_get(msc_a, (trans_type == TRANS_GCC) ? MSC_A_USE_GCC : MSC_A_USE_BCC); |
| 1436 | trans->msc_a = msc_a; |
| 1437 | trans->dlci = 0; /* main DCCH */ |
| 1438 | |
| 1439 | return trans; |
| 1440 | } |
| 1441 | |
| 1442 | /* Receive GCC/BCC messages from calling subscriber, depending on the PDISC used. */ |
| 1443 | int gsm44068_rcv_bcc_gcc(struct msc_a *msc_a, struct gsm_trans *trans, struct msgb *msg) |
| 1444 | { |
| 1445 | struct gsm48_hdr *gh = msgb_l3(msg); |
| 1446 | uint8_t msg_type = gsm48_hdr_msg_type(gh); |
| 1447 | uint8_t pdisc = gsm48_hdr_pdisc(gh); |
| 1448 | uint8_t transaction_id = gsm48_hdr_trans_id_flip_ti(gh); |
| 1449 | enum trans_type trans_type = (pdisc == GSM48_PDISC_GROUP_CC) ? TRANS_GCC : TRANS_BCC; |
| 1450 | |
| 1451 | uint8_t key_seq; |
| 1452 | bool talker_prio_requested; |
| 1453 | bool with_talker_prio; |
| 1454 | uint8_t talker_prio; |
| 1455 | struct gsm48_classmark2 cm2; |
| 1456 | struct osmo_mobile_identity mi; |
| 1457 | uint32_t callref; |
| 1458 | bool with_prio; |
| 1459 | uint8_t prio; |
| 1460 | char user_user[64] = ""; |
| 1461 | uint8_t cause; |
| 1462 | uint8_t diag[256]; |
| 1463 | uint8_t diag_len; |
| 1464 | bool with_call_state; |
| 1465 | enum osmo_gsm44068_call_state call_state; |
| 1466 | bool with_state_attrs; |
| 1467 | uint8_t da, ua, comm, oi; |
| 1468 | int rc = 0; |
| 1469 | |
| 1470 | /* Remove sequence number (bit 7) from message type. */ |
| 1471 | msg_type &= 0xbf; |
| 1472 | |
| 1473 | /* Parse messages. */ |
| 1474 | switch (msg_type) { |
| 1475 | case OSMO_GSM44068_MSGT_SETUP: |
| 1476 | rc = gsm44068_rx_setup(msg, &talker_prio_requested, &talker_prio, &callref, &with_prio, &prio, |
| 1477 | user_user); |
| 1478 | break; |
| 1479 | case OSMO_GSM44068_MSGT_IMMEDIATE_SETUP: |
| 1480 | case OSMO_GSM44068_MSGT_IMMEDIATE_SETUP_2: |
| 1481 | rc = gsm44068_rx_immediate_setup(msg, &talker_prio, &key_seq, &cm2, &mi, &callref, &with_prio, &prio, |
| 1482 | user_user); |
| 1483 | break; |
| 1484 | case OSMO_GSM44068_MSGT_STATUS: |
| 1485 | rc = gsm44068_rx_status(msg, &cause, diag, &diag_len, &with_call_state, &call_state, |
| 1486 | &with_state_attrs, &da, &ua, &comm, &oi); |
| 1487 | break; |
| 1488 | case OSMO_GSM44068_MSGT_TERMINATION_REQUEST: |
| 1489 | rc = gsm44068_rx_termination_req(msg, &callref, &with_prio, &prio, &with_talker_prio, &talker_prio); |
| 1490 | break; |
| 1491 | default: |
| 1492 | LOG_GCC(trans, LOGL_ERROR, "Invalid message type: 0x%02x\n", msg_type); |
| 1493 | return -EINVAL; |
| 1494 | } |
| 1495 | if (rc < 0) |
| 1496 | return rc; |
| 1497 | |
| 1498 | /* Find transaction, if called from msc_a. */ |
| 1499 | if (!trans) |
| 1500 | trans = trans_find_by_id(msc_a, trans_type, transaction_id); |
| 1501 | |
| 1502 | /* Create transaction for SETUP message. */ |
| 1503 | if (!trans) { |
| 1504 | trans = trans_create_bcc_gcc(msc_a, trans_type, transaction_id, pdisc, msg_type, callref); |
| 1505 | if (!trans) |
| 1506 | return -EINVAL; |
| 1507 | } else { |
| 1508 | /* A phone may not call while a VGCS is already active */ |
| 1509 | if (msg_type == OSMO_GSM44068_MSGT_IMMEDIATE_SETUP |
| 1510 | || msg_type == OSMO_GSM44068_MSGT_SETUP |
| 1511 | || msg_type == OSMO_GSM44068_MSGT_IMMEDIATE_SETUP_2) { |
| 1512 | LOG_GCC(trans, LOGL_ERROR, "Received SETUP while call is already set up, rejecting.\n"); |
| 1513 | rc = gsm44068_tx_termination(msc_a, NULL, |
| 1514 | pdisc | (transaction_id << 4), |
| 1515 | OSMO_GSM44068_MSGT_TERMINATION, |
| 1516 | OSMO_GSM44068_CAUSE_NETWORK_FAILURE, NULL, 0); |
| 1517 | if (rc < 0) |
| 1518 | LOG_GCC(trans, LOGL_ERROR, "Failed to send TERMINATION towards MS.\n"); |
| 1519 | return -EINVAL; |
| 1520 | } |
| 1521 | } |
| 1522 | |
| 1523 | /* Handle received GCC messages (trigger state machine). */ |
| 1524 | switch (msg_type) { |
| 1525 | case OSMO_GSM44068_MSGT_IMMEDIATE_SETUP: |
| 1526 | case OSMO_GSM44068_MSGT_SETUP: |
| 1527 | case OSMO_GSM44068_MSGT_IMMEDIATE_SETUP_2: |
| 1528 | LOG_GCC(trans, LOGL_INFO, "Received SETUP.\n"); |
| 1529 | osmo_fsm_inst_dispatch(trans->gcc.fi, VGCS_GCC_EV_USER_SETUP, NULL); |
| 1530 | break; |
| 1531 | case OSMO_GSM44068_MSGT_STATUS: |
| 1532 | LOG_GCC(trans, LOGL_NOTICE, "Received STATUS with cause %d (%s).\n", cause, |
| 1533 | get_value_string(osmo_gsm44068_cause_names, cause)); |
| 1534 | if (diag_len) |
| 1535 | LOG_GCC(trans, LOGL_NOTICE, " -> diagnostics: %s\n", osmo_hexdump(diag, diag_len)); |
| 1536 | if (with_call_state) |
| 1537 | LOG_GCC(trans, LOGL_NOTICE, " -> call state %s\n", |
| 1538 | get_value_string(osmo_gsm44068_call_state_names, call_state)); |
| 1539 | break; |
| 1540 | case OSMO_GSM44068_MSGT_TERMINATION_REQUEST: |
| 1541 | LOG_GCC(trans, LOGL_INFO, "Received TERMINATRION REQUEST.\n"); |
| 1542 | if (callref != trans->callref) { |
| 1543 | LOG_GCC(trans, LOGL_NOTICE, "Received callref 0x%x does not match!\n", callref); |
| 1544 | break; |
| 1545 | } |
| 1546 | osmo_fsm_inst_dispatch(trans->gcc.fi, VGCS_GCC_EV_USER_TERM, NULL); |
| 1547 | break; |
| 1548 | } |
| 1549 | |
| 1550 | return 0; |
| 1551 | } |
| 1552 | |
| 1553 | static void bss_clear(struct vgcs_bss *bss, uint8_t cause, bool notify_trans); |
| 1554 | |
| 1555 | /* Call Control Specific transaction release. |
| 1556 | * gets called by trans_free, DO NOT CALL YOURSELF! */ |
| 1557 | void gsm44068_bcc_gcc_trans_free(struct gsm_trans *trans) |
| 1558 | { |
| 1559 | struct vgcs_bss *bss, *bss2; |
| 1560 | |
Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 1561 | /* Free FSM. */ |
Andreas Eversberg | b865c62 | 2023-07-19 10:06:07 +0200 | [diff] [blame] | 1562 | if (trans->gcc.fi) { |
| 1563 | osmo_fsm_inst_state_chg(trans->gcc.fi, VGCS_GCC_ST_N0_NULL, 0, 0); |
Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 1564 | osmo_fsm_inst_term(trans->gcc.fi, OSMO_FSM_TERM_REGULAR, NULL); |
Andreas Eversberg | b865c62 | 2023-07-19 10:06:07 +0200 | [diff] [blame] | 1565 | } |
Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 1566 | |
| 1567 | /* Remove relations to cells. |
| 1568 | * We must loop safe, because bss_clear() will detach every call control instance from list. */ |
| 1569 | llist_for_each_entry_safe(bss, bss2, &trans->gcc.bss_list, list) |
| 1570 | osmo_fsm_inst_dispatch(bss->fi, VGCS_BSS_EV_CLEAR, NULL); |
| 1571 | |
| 1572 | /* Stop inactivity timer. */ |
| 1573 | stop_inactivity_timer(trans); |
| 1574 | } |
| 1575 | |
| 1576 | /* Create a new call from VTY command. */ |
| 1577 | const char *vgcs_vty_initiate(struct gsm_network *gsmnet, struct gcr *gcr) |
| 1578 | { |
| 1579 | enum trans_type trans_type; |
| 1580 | uint32_t callref; |
| 1581 | struct gsm_trans *trans; |
| 1582 | |
| 1583 | /* Get callref from stored suffix. Caller cannot choose a prefix. */ |
| 1584 | trans_type = gcr->trans_type; |
| 1585 | callref = atoi(gcr->group_id); |
| 1586 | |
| 1587 | /* Check if callref already exists. */ |
| 1588 | trans = trans_find_by_callref(gsmnet, trans_type, callref); |
| 1589 | if (trans) { |
| 1590 | LOG_GCC(trans, LOGL_INFO, "Call to existing %s with callref %s, rejecting!\n", |
| 1591 | trans_type_name(trans_type), gsm44068_group_id_string(callref)); |
| 1592 | return "Call already exists."; |
| 1593 | } |
| 1594 | |
| 1595 | /* Create transaction, uplink is free. */ |
| 1596 | trans = trans_alloc_vgcs(gsmnet, NULL, trans_type, 0, callref, gcr, false); |
| 1597 | if (!trans) { |
| 1598 | LOG_GCC(trans, LOGL_ERROR, "No memory for trans.\n"); |
| 1599 | return "Failed to create call."; |
| 1600 | } |
| 1601 | |
| 1602 | LOG_GCC(trans, LOGL_INFO, "VTY initiates call.\n"); |
| 1603 | osmo_fsm_inst_dispatch(trans->gcc.fi, VGCS_GCC_EV_NET_SETUP, NULL); |
| 1604 | |
| 1605 | return NULL; |
| 1606 | } |
| 1607 | |
| 1608 | /* Destroy a call from VTY command. */ |
| 1609 | const char *vgcs_vty_terminate(struct gsm_network *gsmnet, struct gcr *gcr) |
| 1610 | { |
| 1611 | enum trans_type trans_type; |
| 1612 | uint32_t callref; |
| 1613 | struct gsm_trans *trans; |
| 1614 | |
| 1615 | /* Get callref from stored suffix. Caller cannot choose a prefix. */ |
| 1616 | trans_type = gcr->trans_type; |
| 1617 | callref = atoi(gcr->group_id); |
| 1618 | |
| 1619 | /* Check if callref exists. */ |
| 1620 | trans = trans_find_by_callref(gsmnet, trans_type, callref); |
| 1621 | if (!trans) |
| 1622 | return "Call does not exist."; |
| 1623 | |
| 1624 | LOG_GCC(trans, LOGL_INFO, "VTY terminates call.\n"); |
| 1625 | osmo_fsm_inst_dispatch(trans->gcc.fi, VGCS_GCC_EV_NET_TERM, NULL); |
| 1626 | |
| 1627 | return NULL; |
| 1628 | } |
| 1629 | |
| 1630 | /* |
| 1631 | * BSS state machine - handles all BSS "call control" instances |
| 1632 | */ |
| 1633 | |
| 1634 | static const struct value_string vgcs_bss_fsm_event_names[] = { |
| 1635 | OSMO_VALUE_STRING(VGCS_BSS_EV_SETUP), |
| 1636 | OSMO_VALUE_STRING(VGCS_BSS_EV_SETUP_ACK), |
| 1637 | OSMO_VALUE_STRING(VGCS_BSS_EV_SETUP_REFUSE), |
| 1638 | OSMO_VALUE_STRING(VGCS_BSS_EV_ACTIVE_OR_FAIL), |
| 1639 | OSMO_VALUE_STRING(VGCS_BSS_EV_UL_REQUEST), |
| 1640 | OSMO_VALUE_STRING(VGCS_BSS_EV_UL_REQUEST_CNF), |
| 1641 | OSMO_VALUE_STRING(VGCS_BSS_EV_UL_APP_DATA), |
| 1642 | OSMO_VALUE_STRING(VGCS_BSS_EV_BSS_DTAP), |
| 1643 | OSMO_VALUE_STRING(VGCS_BSS_EV_UL_RELEASE), |
| 1644 | OSMO_VALUE_STRING(VGCS_BSS_EV_CLEAR), |
| 1645 | OSMO_VALUE_STRING(VGCS_BSS_EV_CLOSE), |
| 1646 | OSMO_VALUE_STRING(VGCS_BSS_EV_RELEASED), |
| 1647 | { } |
| 1648 | }; |
| 1649 | |
| 1650 | /* Blocks or unblocks uplinks of a BSS. */ |
| 1651 | static int update_uplink_state(struct vgcs_bss *bss, bool uplink_busy) |
| 1652 | { |
| 1653 | struct ran_msg ran_msg; |
| 1654 | int rc; |
| 1655 | |
| 1656 | if (uplink_busy) { |
| 1657 | /* Send UPLINK SEIZED COMMAND to BSS. */ |
| 1658 | LOG_BSS(bss, LOGL_DEBUG, "Sending (VGCS) UPLINK SEIZED COMMAND towards BSS.\n"); |
| 1659 | ran_msg = (struct ran_msg){ |
| 1660 | .msg_type = RAN_MSG_UPLINK_SEIZED_CMD, |
| 1661 | .uplink_seized_cmd = { |
| 1662 | .cause = GSM0808_CAUSE_CALL_CONTROL, |
| 1663 | }, |
| 1664 | }; |
| 1665 | } else { |
| 1666 | /* Send UPLINK RELEASE COMMAND to BSS. */ |
| 1667 | LOG_BSS(bss, LOGL_DEBUG, "Sending (VGCS) UPLINK RELEASE COMMAND towards BSS.\n"); |
| 1668 | ran_msg = (struct ran_msg){ |
| 1669 | .msg_type = RAN_MSG_UPLINK_RELEASE_CMD, |
| 1670 | .uplink_release_cmd = { |
| 1671 | .cause = GSM0808_CAUSE_CALL_CONTROL, |
| 1672 | }, |
| 1673 | }; |
| 1674 | } |
| 1675 | |
| 1676 | rc = ran_encode_and_send(bss->fi, &ran_msg, bss->conn, false); |
| 1677 | |
| 1678 | return rc; |
| 1679 | } |
| 1680 | |
| 1681 | /* Clear the connection towards BSS. |
| 1682 | * The instance is removed soon, so it is detached from transaction and cells. */ |
| 1683 | static void bss_clear(struct vgcs_bss *bss, uint8_t cause, bool notify_trans) |
| 1684 | { |
| 1685 | struct ran_msg ran_msg; |
| 1686 | struct gsm_trans *trans = bss->trans; |
| 1687 | struct vgcs_bss_cell *cell, *cell2; |
| 1688 | |
| 1689 | /* Must detach us from transaction. */ |
| 1690 | if (bss->trans) { |
| 1691 | /* Remove pointer to talking BSS and cell. */ |
| 1692 | if (bss == bss->trans->gcc.uplink_bss) { |
| 1693 | bss->trans->gcc.uplink_bss = NULL; |
| 1694 | bss->trans->gcc.uplink_cell = NULL; |
| 1695 | } |
| 1696 | llist_del(&bss->list); |
| 1697 | bss->trans = NULL; |
| 1698 | } |
| 1699 | |
| 1700 | /* Change state. */ |
| 1701 | osmo_fsm_inst_state_chg(bss->fi, VGCS_BSS_ST_RELEASE, 0, 0); |
| 1702 | |
| 1703 | /* Send Clear Command to BSS. */ |
| 1704 | ran_msg = (struct ran_msg){ |
| 1705 | .msg_type = RAN_MSG_CLEAR_COMMAND, |
| 1706 | .clear_command = { |
| 1707 | .gsm0808_cause = cause, |
| 1708 | }, |
| 1709 | }; |
| 1710 | if (bss->conn) { |
| 1711 | LOG_BSS(bss, LOGL_DEBUG, "Sending CLEAR COMMAND for call controling channel.\n"); |
| 1712 | ran_encode_and_send(bss->fi, &ran_msg, bss->conn, false); |
| 1713 | } |
| 1714 | |
| 1715 | /* Trigger clear of all cells. Be safe, because the process will remove cells from list. */ |
| 1716 | llist_for_each_entry_safe(cell, cell2, &bss->cell_list, list_bss) |
| 1717 | osmo_fsm_inst_dispatch(cell->fi, VGCS_CELL_EV_CLEAR, NULL); |
| 1718 | |
| 1719 | /* Detach us from all BSS, if still linked */ |
| 1720 | llist_for_each_entry_safe(cell, cell2, &bss->cell_list, list_bss) { |
| 1721 | llist_del(&cell->list_bss); |
| 1722 | cell->bss = NULL; |
| 1723 | } |
| 1724 | |
| 1725 | /* If all BS are gone, notify calling subscriber process. */ |
| 1726 | if (notify_trans && trans && llist_empty(&trans->gcc.bss_list)) { |
| 1727 | LOG_BSS(bss, LOGL_DEBUG, "Notify calling user process, that all BSSs are cleared.\n"); |
| 1728 | osmo_fsm_inst_dispatch(trans->gcc.fi, VGCS_GCC_EV_BSS_RELEASED, NULL); |
| 1729 | } |
| 1730 | } |
| 1731 | |
| 1732 | /* When finally the BSS connection is released. (CLEAR COMPLETE response) |
| 1733 | * The instance is removed, so it is detached from transaction and cells, if not already. */ |
| 1734 | static void bss_destroy(struct vgcs_bss *bss) |
| 1735 | { |
| 1736 | struct vgcs_bss_cell *cell, *cell2; |
| 1737 | |
| 1738 | LOG_BSS(bss, LOGL_DEBUG, "Removing BSS call controling instance.\n"); |
| 1739 | |
| 1740 | /* Must detach us from transaction, if not already. */ |
| 1741 | if (bss->trans) { |
| 1742 | /* Remove pointer to talking BSS and cell. */ |
| 1743 | if (bss == bss->trans->gcc.uplink_bss) { |
| 1744 | bss->trans->gcc.uplink_bss = NULL; |
| 1745 | bss->trans->gcc.uplink_cell = NULL; |
| 1746 | } |
| 1747 | llist_del(&bss->list); |
| 1748 | bss->trans = NULL; |
| 1749 | } |
| 1750 | |
| 1751 | /* Detach us from RAN connection. */ |
| 1752 | if (bss->conn) { |
| 1753 | if (bss->conn->vgcs.bss == bss) |
| 1754 | bss->conn->vgcs.bss = NULL; |
| 1755 | if (bss->conn->vgcs.cell == bss) |
| 1756 | bss->conn->vgcs.cell = NULL; |
| 1757 | ran_conn_close(bss->conn); |
| 1758 | bss->conn = NULL; |
| 1759 | } |
| 1760 | |
| 1761 | /* Detach us from all BSS, if still linked */ |
| 1762 | llist_for_each_entry_safe(cell, cell2, &bss->cell_list, list_bss) { |
| 1763 | llist_del(&cell->list_bss); |
| 1764 | cell->bss = NULL; |
| 1765 | } |
| 1766 | |
| 1767 | /* Free FSM. (should be allocated) */ |
| 1768 | osmo_fsm_inst_state_chg(bss->fi, VGCS_BSS_ST_NULL, 0, 0); |
| 1769 | osmo_fsm_inst_term(bss->fi, OSMO_FSM_TERM_REGULAR, NULL); |
| 1770 | } |
| 1771 | |
| 1772 | /* Get identity of talker. |
| 1773 | * This is required to detect if the talker is the calling subscriber. */ |
| 1774 | static int talker_identity(struct vgcs_bss *bss, uint8_t *l3, int l3_len) |
| 1775 | { |
| 1776 | struct osmo_mobile_identity mi; |
| 1777 | int rc; |
| 1778 | |
| 1779 | puts(osmo_hexdump(l3, l3_len)); |
| 1780 | rc = osmo_mobile_identity_decode_from_l3_buf(&mi, l3, l3_len, false); |
| 1781 | if (rc < 0) { |
| 1782 | LOG_BSS(bss, LOGL_DEBUG, "Talker's Identity cannot be decoded.\n"); |
| 1783 | return rc; |
| 1784 | } |
| 1785 | |
| 1786 | switch (mi.type) { |
| 1787 | case GSM_MI_TYPE_IMSI: |
| 1788 | if (!bss->trans->vsub) |
| 1789 | break; |
| 1790 | LOG_BSS(bss, LOGL_DEBUG, "Talker's sends IMSI %s, originator has IMSI %s.\n", |
| 1791 | mi.imsi, bss->trans->vsub->imsi); |
| 1792 | if (!strcmp(mi.imsi, bss->trans->vsub->imsi)) |
| 1793 | return 1; |
| 1794 | break; |
| 1795 | case GSM_MI_TYPE_TMSI: |
| 1796 | if (!bss->trans->vsub) |
| 1797 | break; |
| 1798 | LOG_BSS(bss, LOGL_DEBUG, "Talker's sends TMSI 0x%08x, originator has TMSI 0x%08x.\n", |
| 1799 | mi.tmsi, bss->trans->vsub->tmsi); |
| 1800 | if (mi.tmsi == bss->trans->vsub->tmsi) |
| 1801 | return 1; |
| 1802 | break; |
| 1803 | default: |
| 1804 | LOG_BSS(bss, LOGL_DEBUG, "Talker's Identity is not IMSI nor TMSI.\n"); |
| 1805 | return -EINVAL; |
| 1806 | } |
| 1807 | |
| 1808 | return 0; |
| 1809 | } |
| 1810 | |
| 1811 | static void vgcs_bss_fsm_null(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 1812 | { |
| 1813 | struct vgcs_bss *bss = fi->priv; |
| 1814 | struct ran_msg ran_msg; |
| 1815 | |
| 1816 | switch (event) { |
| 1817 | case VGCS_BSS_EV_SETUP: |
| 1818 | /* Change state. */ |
| 1819 | osmo_fsm_inst_state_chg(fi, VGCS_BSS_ST_SETUP, 0, 0); |
| 1820 | /* Send VGCS/VBS SETUP to BSS. */ |
| 1821 | LOG_BSS(bss, LOGL_DEBUG, "Sending VGCS/VBS SETUP towards BSS.\n"); |
| 1822 | ran_msg = (struct ran_msg){ |
| 1823 | .msg_type = RAN_MSG_VGCS_VBS_SETUP, |
| 1824 | .vgcs_vbs_setup = { |
| 1825 | .callref = { |
| 1826 | .sf = (bss->trans->type == TRANS_GCC), |
| 1827 | }, |
| 1828 | .vgcs_feature_flags_present = true, |
| 1829 | }, |
| 1830 | }; |
| 1831 | osmo_store32be_ext(bss->callref >> 3, &ran_msg.vgcs_vbs_setup.callref.call_ref_hi, 3); |
| 1832 | ran_msg.vgcs_vbs_setup.callref.call_ref_lo = bss->callref & 0x7; |
| 1833 | /* First message, so we must set "initial" to "true". */ |
| 1834 | ran_encode_and_send(fi, &ran_msg, bss->conn, true); |
| 1835 | break; |
| 1836 | case VGCS_BSS_EV_CLEAR: |
| 1837 | /* The calling user process requested clearing of VGCS/VBS call. */ |
| 1838 | LOG_BSS(bss, LOGL_DEBUG, "Received clearing from calling user process.\n"); |
| 1839 | bss_clear(bss, GSM0808_CAUSE_CALL_CONTROL, false); |
| 1840 | break; |
| 1841 | default: |
| 1842 | OSMO_ASSERT(false); |
| 1843 | } |
| 1844 | } |
| 1845 | |
| 1846 | static void vgcs_bss_fsm_setup(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 1847 | { |
| 1848 | struct vgcs_bss *bss = fi->priv; |
| 1849 | struct vgcs_bss_cell *cell, *cell2; |
| 1850 | |
| 1851 | switch (event) { |
| 1852 | case VGCS_BSS_EV_SETUP_ACK: |
| 1853 | /* Receive VGCS/VBS SETUP ACK from BSS. */ |
| 1854 | LOG_BSS(bss, LOGL_DEBUG, "Received VGCS/VBS SETUP ACK from BSS.\n"); |
| 1855 | /* Send current uplink state to this BSS. */ |
| 1856 | if (bss->trans) |
| 1857 | update_uplink_state(bss, bss->trans->gcc.uplink_busy); |
| 1858 | /* Change state. */ |
| 1859 | osmo_fsm_inst_state_chg(fi, VGCS_BSS_ST_ASSIGNMENT, 0, 0); |
| 1860 | /* Trigger VGCS/VBS ASSIGNMENT */ |
| 1861 | llist_for_each_entry_safe(cell, cell2, &bss->cell_list, list_bss) |
| 1862 | osmo_fsm_inst_dispatch(cell->fi, VGCS_CELL_EV_ASSIGN, NULL); |
| 1863 | /* If all failed, clear call. */ |
| 1864 | if (llist_empty(&bss->cell_list)) { |
| 1865 | LOG_BSS(bss, LOGL_NOTICE, "All VGCS/VBS assignments failed.\n"); |
| 1866 | bss_clear(bss, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC, true); |
| 1867 | break; |
| 1868 | } |
| 1869 | break; |
| 1870 | case VGCS_BSS_EV_SETUP_REFUSE: |
| 1871 | /* Received VGCS/VBS SETUP REFUSE from BSS. */ |
| 1872 | LOG_BSS(bss, LOGL_NOTICE, "Received VGCS/VBS SETUP REFUSE from BSS.\n"); |
| 1873 | bss_clear(bss, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC, true); |
| 1874 | break; |
| 1875 | case VGCS_BSS_EV_CLEAR: |
| 1876 | /* The calling user process requested clearing of VGCS/VBS call. */ |
| 1877 | LOG_BSS(bss, LOGL_DEBUG, "Received clearing from calling user process.\n"); |
| 1878 | bss_clear(bss, GSM0808_CAUSE_CALL_CONTROL, false); |
| 1879 | break; |
| 1880 | case VGCS_BSS_EV_CLOSE: |
| 1881 | /* The SCCP connection from the MSC has been closed. */ |
| 1882 | LOG_BSS(bss, LOGL_NOTICE, "Received SCCP connecting closing from MSC.\n"); |
| 1883 | if (bss->conn) { |
| 1884 | bss->conn->vgcs.bss = NULL; |
| 1885 | bss->conn = NULL; |
| 1886 | } |
| 1887 | bss_clear(bss, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC, true); |
| 1888 | break; |
| 1889 | default: |
| 1890 | OSMO_ASSERT(false); |
| 1891 | } |
| 1892 | } |
| 1893 | |
| 1894 | static void vgcs_bss_fsm_assignment(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 1895 | { |
| 1896 | struct vgcs_bss *bss = fi->priv; |
| 1897 | struct vgcs_bss_cell *c; |
| 1898 | bool assigned; |
| 1899 | |
| 1900 | switch (event) { |
| 1901 | case VGCS_BSS_EV_ACTIVE_OR_FAIL: |
| 1902 | /* If all gone, clear call. */ |
| 1903 | if (llist_empty(&bss->cell_list)) { |
| 1904 | LOG_BSS(bss, LOGL_NOTICE, "All VGCS/VBS assignments failed.\n"); |
| 1905 | bss_clear(bss, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC, true); |
| 1906 | break; |
| 1907 | } |
| 1908 | /* Is there a response for all cells? |
| 1909 | * This means that all the channels have a positive response |
| 1910 | * There is no channel with negative response, because a |
| 1911 | * negative response will remove the channel. */ |
| 1912 | assigned = true; |
| 1913 | llist_for_each_entry(c, &bss->cell_list, list_bss) { |
| 1914 | if (!c->assigned) |
| 1915 | assigned = false; |
| 1916 | } |
| 1917 | if (!assigned) |
| 1918 | break; |
| 1919 | LOG_BSS(bss, LOGL_DEBUG, "All VGCS/VBS assignments have responded.\n"); |
| 1920 | /* Change state. */ |
| 1921 | osmo_fsm_inst_state_chg(fi, VGCS_BSS_ST_ACTIVE, 0, 0); |
| 1922 | /* Notify calling subscriber process. */ |
| 1923 | LOG_BSS(bss, LOGL_DEBUG, "Notify calling user process, that all BSSs are connected.\n"); |
| 1924 | if (bss->trans) |
| 1925 | osmo_fsm_inst_dispatch(bss->trans->gcc.fi, VGCS_GCC_EV_BSS_ESTABLISHED, NULL); |
| 1926 | break; |
| 1927 | case VGCS_BSS_EV_CLEAR: |
| 1928 | /* The calling user process requested clearing of VGCS/VBS call. */ |
| 1929 | LOG_BSS(bss, LOGL_DEBUG, "Received clearing from calling user process.\n"); |
| 1930 | bss_clear(bss, GSM0808_CAUSE_CALL_CONTROL, false); |
| 1931 | break; |
| 1932 | case VGCS_BSS_EV_CLOSE: |
| 1933 | /* The SCCP connection from the MSC has been closed. */ |
| 1934 | LOG_BSS(bss, LOGL_NOTICE, "Received SCCP connecting closing from MSC.\n"); |
| 1935 | if (bss->conn) { |
| 1936 | bss->conn->vgcs.bss = NULL; |
| 1937 | bss->conn = NULL; |
| 1938 | } |
| 1939 | bss_clear(bss, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC, true); |
| 1940 | break; |
| 1941 | default: |
| 1942 | OSMO_ASSERT(false); |
| 1943 | } |
| 1944 | } |
| 1945 | |
| 1946 | static void vgcs_bss_fsm_active(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 1947 | { |
| 1948 | struct vgcs_bss *bss = fi->priv, *other; |
| 1949 | struct ran_msg *rx_ran_msg = data; |
| 1950 | struct ran_msg tx_ran_msg; |
| 1951 | int rc; |
| 1952 | |
| 1953 | switch (event) { |
| 1954 | case VGCS_BSS_EV_UL_REQUEST: |
| 1955 | LOG_BSS(bss, LOGL_DEBUG, "Listener changed to talker.\n"); |
| 1956 | if (!bss->trans) |
| 1957 | break; |
| 1958 | /* Someone is talking. Check if there is no other uplink already busy. |
| 1959 | * This should not happen, since all other cells are blocked (SEIZED) as soon as the uplink was |
| 1960 | * requested. This may happen due to a race condition, where the uplink was requested before the |
| 1961 | * UPLINK SEIZED COMMAND has been received by BSS. */ |
| 1962 | if (bss->trans->gcc.uplink_busy) { |
| 1963 | /* Send UPLINK REJECT COMMAND to BSS. */ |
| 1964 | LOG_BSS(bss, LOGL_DEBUG, "Sending (VGCS) UPLINK REJECT COMMAND towards BSS.\n"); |
| 1965 | tx_ran_msg = (struct ran_msg){ |
| 1966 | .msg_type = RAN_MSG_UPLINK_REJECT_CMD, |
| 1967 | .uplink_reject_cmd = { |
| 1968 | .cause = GSM0808_CAUSE_CALL_CONTROL, |
| 1969 | }, |
| 1970 | }; |
| 1971 | ran_encode_and_send(fi, &tx_ran_msg, bss->conn, false); |
| 1972 | break; |
| 1973 | } |
| 1974 | /* Send UPLINK REQUEST ACKNOWLEDGE to BSS. */ |
| 1975 | LOG_BSS(bss, LOGL_DEBUG, "Sending (VGCS) UPLINK REQUEST ACKNOWLEDGE towards BSS.\n"); |
| 1976 | tx_ran_msg = (struct ran_msg){ |
| 1977 | .msg_type = RAN_MSG_UPLINK_REQUEST_ACK, |
| 1978 | }; |
| 1979 | ran_encode_and_send(fi, &tx_ran_msg, bss->conn, false); |
| 1980 | /* Set the busy flag and block all other cells. */ |
| 1981 | bss->trans->gcc.uplink_bss = bss; |
| 1982 | bss->trans->gcc.uplink_busy = true; |
| 1983 | bss->trans->gcc.uplink_originator = false; |
| 1984 | llist_for_each_entry(other, &bss->trans->gcc.bss_list, list) { |
| 1985 | if (other == bss) |
| 1986 | continue; |
| 1987 | /* Update uplink state. */ |
| 1988 | update_uplink_state(bss, bss->trans->gcc.uplink_busy); |
| 1989 | } |
| 1990 | /* Stop inactivity timer. */ |
| 1991 | stop_inactivity_timer(bss->trans); |
| 1992 | break; |
| 1993 | case VGCS_BSS_EV_UL_REQUEST_CNF: |
| 1994 | LOG_BSS(bss, LOGL_DEBUG, "Talker established uplink.\n"); |
| 1995 | if (!bss->trans) |
| 1996 | break; |
| 1997 | if (!bss->trans->gcc.uplink_busy || bss->trans->gcc.uplink_bss != bss) { |
| 1998 | LOG_BSS(bss, LOGL_ERROR, "Got UL REQUEST CNF, but we did not granted uplink.\n"); |
| 1999 | break; |
| 2000 | } |
| 2001 | /* Determine if talker is the originator of the call. */ |
| 2002 | rc = talker_identity(bss, rx_ran_msg->uplink_request_cnf.l3.l3, |
| 2003 | rx_ran_msg->uplink_request_cnf.l3.l3_len); |
| 2004 | if (rc > 0) { |
| 2005 | bss->trans->gcc.uplink_originator = true; |
| 2006 | LOG_BSS(bss, LOGL_DEBUG, "Talker is the originator of the call.\n"); |
| 2007 | } |
| 2008 | /* Set parameter. */ |
| 2009 | set_parameter(bss->trans); |
| 2010 | /* Set cell of current talker. */ |
| 2011 | set_uplink_cell(bss, &rx_ran_msg->uplink_request_cnf.cell_identifier, 0); |
| 2012 | /* Set MGW conference. */ |
| 2013 | set_mgw_conference(bss->trans); |
| 2014 | break; |
| 2015 | case VGCS_BSS_EV_UL_APP_DATA: |
| 2016 | LOG_BSS(bss, LOGL_DEBUG, "Talker sends application data on uplink.\n"); |
| 2017 | if (!bss->trans) |
| 2018 | break; |
| 2019 | if (!bss->trans->gcc.uplink_busy || bss->trans->gcc.uplink_bss != bss) { |
| 2020 | LOG_BSS(bss, LOGL_ERROR, "Got UP APP DATA, but we did not granted uplink.\n"); |
| 2021 | break; |
| 2022 | } |
| 2023 | // FIXME: Use L3 info and feed to app. |
| 2024 | break; |
| 2025 | case VGCS_BSS_EV_BSS_DTAP: |
| 2026 | LOG_BSS(bss, LOGL_DEBUG, "Talker sends DTAP message.\n"); |
| 2027 | if (!bss->trans) |
| 2028 | break; |
| 2029 | if (!bss->trans->gcc.uplink_busy || bss->trans->gcc.uplink_bss != bss) { |
| 2030 | LOG_BSS(bss, LOGL_ERROR, "Got DTAP from BSS, but we did not granted uplink.\n"); |
| 2031 | break; |
| 2032 | } |
| 2033 | gsm44068_rcv_bcc_gcc(NULL, bss->trans, rx_ran_msg->dtap); |
| 2034 | break; |
| 2035 | case VGCS_BSS_EV_UL_RELEASE: |
| 2036 | LOG_BSS(bss, LOGL_DEBUG, "Talker released uplink.\n"); |
| 2037 | if (!bss->trans) |
| 2038 | break; |
| 2039 | if (bss->trans->type == TRANS_BCC) { |
| 2040 | LOG_BSS(bss, LOGL_DEBUG, "This is a broadcast call, terminating call.\n"); |
| 2041 | gcc_terminate_and_destroy(bss->trans, OSMO_GSM44068_CAUSE_NORMAL_CALL_CLEARING); |
| 2042 | break; |
| 2043 | } |
| 2044 | if (!bss->trans->gcc.uplink_busy) { |
| 2045 | LOG_BSS(bss, LOGL_NOTICE, "Got uplink release, but no uplink busy.\n"); |
| 2046 | break; |
| 2047 | } |
| 2048 | /* Talker release the uplink. Ignore, if not from the current talking cell. */ |
| 2049 | if (bss->trans->gcc.uplink_bss != bss) { |
| 2050 | LOG_BSS(bss, LOGL_NOTICE, "Got uplink release, but uplink busy in other cell.\n"); |
| 2051 | break; |
| 2052 | } |
| 2053 | /* Clear the busy flag and unblock all other cells. */ |
| 2054 | bss->trans->gcc.uplink_bss = NULL; |
| 2055 | bss->trans->gcc.uplink_cell = NULL; |
| 2056 | bss->trans->gcc.uplink_busy = false; |
| 2057 | llist_for_each_entry(other, &bss->trans->gcc.bss_list, list) { |
| 2058 | if (other == bss) |
| 2059 | continue; |
| 2060 | /* Update uplink state. */ |
| 2061 | if (bss->trans) |
| 2062 | update_uplink_state(bss, bss->trans->gcc.uplink_busy); |
| 2063 | } |
| 2064 | /* Set MGW conference. */ |
| 2065 | set_mgw_conference(bss->trans); |
| 2066 | /* Start inactivity timer. */ |
| 2067 | start_inactivity_timer(bss->trans); |
| 2068 | break; |
| 2069 | case VGCS_BSS_EV_CLEAR: |
| 2070 | /* The calling user process requested clearing of VGCS/VBS call. */ |
| 2071 | LOG_BSS(bss, LOGL_DEBUG, "Received clearing from calling user process.\n"); |
| 2072 | bss_clear(bss, GSM0808_CAUSE_CALL_CONTROL, false); |
| 2073 | break; |
| 2074 | case VGCS_BSS_EV_CLOSE: |
| 2075 | /* The SCCP connection from the MSC has been closed. */ |
| 2076 | LOG_BSS(bss, LOGL_NOTICE, "Received SCCP connecting closing from MSC.\n"); |
| 2077 | if (bss->conn) { |
| 2078 | bss->conn->vgcs.bss = NULL; |
| 2079 | bss->conn = NULL; |
| 2080 | } |
| 2081 | bss_clear(bss, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC, true); |
| 2082 | break; |
| 2083 | default: |
| 2084 | OSMO_ASSERT(false); |
| 2085 | } |
| 2086 | } |
| 2087 | |
| 2088 | static void vgcs_bss_fsm_release(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 2089 | { |
| 2090 | struct vgcs_bss *bss = fi->priv; |
| 2091 | |
| 2092 | switch (event) { |
| 2093 | case VGCS_BSS_EV_CLOSE: |
| 2094 | /* The SCCP connection from the MSC has been closed while waitring fro CLEAR COMPLETE. */ |
| 2095 | LOG_BSS(bss, LOGL_NOTICE, "Received SCCP closing collision.\n"); |
| 2096 | bss_destroy(bss); |
| 2097 | break; |
| 2098 | case VGCS_BSS_EV_RELEASED: |
| 2099 | LOG_BSS(bss, LOGL_DEBUG, "Received CLEAR COMPLETE from BSS, we are done!\n"); |
| 2100 | bss_destroy(bss); |
| 2101 | break; |
| 2102 | default: |
| 2103 | OSMO_ASSERT(false); |
| 2104 | } |
| 2105 | } |
| 2106 | |
| 2107 | static const struct osmo_fsm_state vgcs_bss_fsm_states[] = { |
| 2108 | [VGCS_BSS_ST_NULL] = { |
| 2109 | .name = "NULL", |
| 2110 | .in_event_mask = S(VGCS_BSS_EV_SETUP) | |
| 2111 | S(VGCS_BSS_EV_CLEAR), |
| 2112 | .out_state_mask = S(VGCS_BSS_ST_SETUP), |
| 2113 | .action = vgcs_bss_fsm_null, |
| 2114 | }, |
| 2115 | [VGCS_BSS_ST_SETUP] = { |
| 2116 | .name = "SETUP sent", |
| 2117 | .in_event_mask = S(VGCS_BSS_EV_SETUP_ACK) | |
| 2118 | S(VGCS_BSS_EV_SETUP_REFUSE) | |
| 2119 | S(VGCS_BSS_EV_CLEAR) | |
| 2120 | S(VGCS_BSS_EV_CLOSE), |
| 2121 | .out_state_mask = S(VGCS_BSS_ST_ASSIGNMENT) | |
| 2122 | S(VGCS_BSS_ST_RELEASE), |
| 2123 | .action = vgcs_bss_fsm_setup, |
| 2124 | }, |
| 2125 | [VGCS_BSS_ST_ASSIGNMENT] = { |
| 2126 | .name = "ASSIGNMENT Sent", |
| 2127 | .in_event_mask = S(VGCS_BSS_EV_ACTIVE_OR_FAIL) | |
| 2128 | S(VGCS_BSS_EV_CLEAR) | |
| 2129 | S(VGCS_BSS_EV_CLOSE), |
| 2130 | .out_state_mask = S(VGCS_BSS_ST_ACTIVE) | |
| 2131 | S(VGCS_BSS_ST_RELEASE), |
| 2132 | .action = vgcs_bss_fsm_assignment, |
| 2133 | }, |
| 2134 | [VGCS_BSS_ST_ACTIVE] = { |
| 2135 | .name = "VGCS/VBS Active", |
| 2136 | .in_event_mask = S(VGCS_BSS_EV_UL_REQUEST) | |
| 2137 | S(VGCS_BSS_EV_UL_REQUEST_CNF) | |
| 2138 | S(VGCS_BSS_EV_UL_APP_DATA) | |
| 2139 | S(VGCS_BSS_EV_BSS_DTAP) | |
| 2140 | S(VGCS_BSS_EV_UL_RELEASE) | |
| 2141 | S(VGCS_BSS_EV_CLEAR) | |
| 2142 | S(VGCS_BSS_EV_CLOSE), |
| 2143 | .out_state_mask = S(VGCS_BSS_ST_RELEASE), |
| 2144 | .action = vgcs_bss_fsm_active, |
| 2145 | }, |
| 2146 | [VGCS_BSS_ST_RELEASE] = { |
| 2147 | .name = "Releasing VGCS/VBS control", |
| 2148 | .in_event_mask = S(VGCS_BSS_EV_CLEAR) | |
| 2149 | S(VGCS_BSS_EV_RELEASED), |
| 2150 | .out_state_mask = S(VGCS_BSS_ST_NULL), |
| 2151 | .action = vgcs_bss_fsm_release, |
| 2152 | }, |
| 2153 | }; |
| 2154 | |
| 2155 | static struct osmo_fsm vgcs_bss_fsm = { |
| 2156 | .name = "vgcs_bss", |
| 2157 | .states = vgcs_bss_fsm_states, |
| 2158 | .num_states = ARRAY_SIZE(vgcs_bss_fsm_states), |
| 2159 | .log_subsys = DASCI, |
| 2160 | .event_names = vgcs_bss_fsm_event_names, |
| 2161 | }; |
| 2162 | |
| 2163 | /* The BSS accepts VGCS/VBS and sends us supported features. */ |
| 2164 | void vgcs_vbs_setup_ack(struct vgcs_bss *bss, const struct ran_msg *ran_msg) |
| 2165 | { |
| 2166 | if (!bss->trans) |
| 2167 | return; |
| 2168 | osmo_fsm_inst_dispatch(bss->fi, VGCS_BSS_EV_SETUP_ACK, (void *)ran_msg); |
| 2169 | } |
| 2170 | |
| 2171 | /* The BSS refuses VGCS/VBS. */ |
| 2172 | void vgcs_vbs_setup_refuse(struct vgcs_bss *bss, const struct ran_msg *ran_msg) |
| 2173 | { |
| 2174 | if (!bss->trans) |
| 2175 | return; |
| 2176 | osmo_fsm_inst_dispatch(bss->fi, VGCS_BSS_EV_SETUP_REFUSE, (void *)ran_msg); |
| 2177 | } |
| 2178 | |
| 2179 | /* The BSS needs more time for VGCS/VBS channel assignment. */ |
| 2180 | void vgcs_vbs_queuing_ind(struct vgcs_bss_cell *cell) |
| 2181 | { |
| 2182 | if (!cell->bss) |
| 2183 | return; |
| 2184 | } |
| 2185 | |
| 2186 | /* A mobile station requests the uplink on a VGCS channel. */ |
| 2187 | void vgcs_uplink_request(struct vgcs_bss *bss, const struct ran_msg *ran_msg) |
| 2188 | { |
| 2189 | if (!bss->trans) |
| 2190 | return; |
| 2191 | osmo_fsm_inst_dispatch(bss->fi, VGCS_BSS_EV_UL_REQUEST, (void *)ran_msg); |
| 2192 | } |
| 2193 | |
| 2194 | /* The uplink on a VGCS channel has been established. */ |
| 2195 | void vgcs_uplink_request_cnf(struct vgcs_bss *bss, const struct ran_msg *ran_msg) |
| 2196 | { |
| 2197 | if (!bss->trans) |
| 2198 | return; |
| 2199 | osmo_fsm_inst_dispatch(bss->fi, VGCS_BSS_EV_UL_REQUEST_CNF, (void *)ran_msg); |
| 2200 | } |
| 2201 | |
| 2202 | /* Application data received on the uplink of a VGCS channel. */ |
| 2203 | void vgcs_app_data(struct vgcs_bss *bss, const struct ran_msg *ran_msg) |
| 2204 | { |
| 2205 | if (!bss->trans) |
| 2206 | return; |
| 2207 | osmo_fsm_inst_dispatch(bss->fi, VGCS_BSS_EV_UL_APP_DATA, (void *)ran_msg); |
| 2208 | } |
| 2209 | |
| 2210 | /* Application data received on the uplink of a VGCS channel. */ |
| 2211 | void vgcs_bss_dtap(struct vgcs_bss *bss, const struct ran_msg *ran_msg) |
| 2212 | { |
| 2213 | if (!bss->trans) |
| 2214 | return; |
| 2215 | osmo_fsm_inst_dispatch(bss->fi, VGCS_BSS_EV_BSS_DTAP, (void *)ran_msg); |
| 2216 | } |
| 2217 | |
| 2218 | /* A mobile station releases the uplink on a VGCS channel. */ |
| 2219 | void vgcs_uplink_release_ind(struct vgcs_bss *bss, const struct ran_msg *ran_msg) |
| 2220 | { |
| 2221 | if (!bss->trans) |
| 2222 | return; |
| 2223 | osmo_fsm_inst_dispatch(bss->fi, VGCS_BSS_EV_UL_RELEASE, (void *)ran_msg); |
| 2224 | } |
| 2225 | |
| 2226 | /* The BSS gives cell status about VGCS/VBS channel. */ |
| 2227 | void vgcs_vbs_assign_status(struct vgcs_bss_cell *cell, const struct ran_msg *ran_msg) |
| 2228 | { |
| 2229 | if (!cell->bss) |
| 2230 | return; |
| 2231 | } |
| 2232 | |
| 2233 | void vgcs_vbs_caller_assign_cpl(struct gsm_trans *trans) |
| 2234 | { |
| 2235 | osmo_fsm_inst_dispatch(trans->gcc.fi, VGCS_GCC_EV_BSS_ASSIGN_CPL, NULL); |
| 2236 | } |
| 2237 | |
| 2238 | void vgcs_vbs_caller_assign_fail(struct gsm_trans *trans) |
| 2239 | { |
| 2240 | osmo_fsm_inst_dispatch(trans->gcc.fi, VGCS_GCC_EV_BSS_ASSIGN_FAIL, NULL); |
| 2241 | } |
| 2242 | |
| 2243 | /* BSS indicated that the channel has been released. */ |
| 2244 | void vgcs_vbs_clear_req(struct vgcs_bss *bss, const struct ran_msg *ran_msg) |
| 2245 | { |
| 2246 | osmo_fsm_inst_dispatch(bss->fi, VGCS_BSS_EV_CLOSE, (void *)ran_msg); |
| 2247 | } |
| 2248 | |
| 2249 | /* BSS indicated that the channel has been released. */ |
| 2250 | void vgcs_vbs_clear_cpl(struct vgcs_bss *bss, const struct ran_msg *ran_msg) |
| 2251 | { |
| 2252 | osmo_fsm_inst_dispatch(bss->fi, VGCS_BSS_EV_RELEASED, (void *)ran_msg); |
| 2253 | } |
| 2254 | |
| 2255 | /* |
| 2256 | * Cell resource state machine - handles all "resource control" instances |
| 2257 | */ |
| 2258 | |
| 2259 | static const struct value_string vgcs_cell_fsm_event_names[] = { |
| 2260 | OSMO_VALUE_STRING(VGCS_CELL_EV_RTP_STREAM_GONE), |
| 2261 | OSMO_VALUE_STRING(VGCS_CELL_EV_RTP_STREAM_ADDR_AVAILABLE), |
| 2262 | OSMO_VALUE_STRING(VGCS_CELL_EV_RTP_STREAM_ESTABLISHED), |
| 2263 | OSMO_VALUE_STRING(VGCS_CELL_EV_ASSIGN), |
| 2264 | OSMO_VALUE_STRING(VGCS_CELL_EV_ASSIGN_RES), |
| 2265 | OSMO_VALUE_STRING(VGCS_CELL_EV_ASSIGN_FAIL), |
| 2266 | OSMO_VALUE_STRING(VGCS_CELL_EV_CLEAR), |
| 2267 | OSMO_VALUE_STRING(VGCS_CELL_EV_CLOSE), |
| 2268 | OSMO_VALUE_STRING(VGCS_CELL_EV_RELEASED), |
| 2269 | { } |
| 2270 | }; |
| 2271 | |
| 2272 | static void cell_destroy(struct vgcs_bss_cell *cell); |
| 2273 | |
| 2274 | /* Clear the connection towards BSS. |
| 2275 | * Relations to the BSS and transaction is removed. */ |
| 2276 | static void cell_clear(struct vgcs_bss_cell *cell, uint8_t cause) |
| 2277 | { |
| 2278 | struct ran_msg ran_msg; |
| 2279 | |
| 2280 | /* Must detach us from BSS. */ |
| 2281 | if (cell->bss) { |
| 2282 | /* Remove pointer to talking channel. */ |
| 2283 | if (cell->bss->trans && cell->bss->trans->gcc.uplink_cell == cell) |
| 2284 | cell->bss->trans->gcc.uplink_cell = NULL; |
| 2285 | llist_del(&cell->list_bss); |
| 2286 | cell->bss = NULL; |
| 2287 | } |
| 2288 | |
| 2289 | /* Change state. */ |
| 2290 | if (cell->fi->state != VGCS_CELL_ST_RELEASE) |
| 2291 | osmo_fsm_inst_state_chg(cell->fi, VGCS_CELL_ST_RELEASE, 0, 0); |
| 2292 | |
| 2293 | /* If there is no event to wait for, we can just destroy. */ |
| 2294 | if (!cell->conn && !cell->rtps) { |
| 2295 | cell_destroy(cell); |
| 2296 | return; |
| 2297 | } |
| 2298 | |
| 2299 | /* Send Clear Command to BSS. */ |
| 2300 | if (cell->conn) { |
| 2301 | ran_msg = (struct ran_msg){ |
| 2302 | .msg_type = RAN_MSG_CLEAR_COMMAND, |
| 2303 | .clear_command = { |
| 2304 | .gsm0808_cause = cause, |
| 2305 | }, |
| 2306 | }; |
| 2307 | LOG_CELL(cell, LOGL_DEBUG, "Sending CLEAR COMMAND for call controling channel.\n"); |
| 2308 | ran_encode_and_send(cell->fi, &ran_msg, cell->conn, false); |
| 2309 | } |
| 2310 | |
| 2311 | /* Clear RTP stream. This may trigger VGCS_CELL_EV_RTP_STREAM_GONE within this release function. */ |
| 2312 | if (cell->rtps) |
| 2313 | rtp_stream_release(cell->rtps); |
| 2314 | } |
| 2315 | |
| 2316 | /* When finally the BSS connection is released. (CLEAR COMPLETE response) |
| 2317 | * Relations to the BSS and transaction is removed, if not already. */ |
| 2318 | static void cell_destroy(struct vgcs_bss_cell *cell) |
| 2319 | { |
| 2320 | struct vgcs_mgw_ep *mgw; |
| 2321 | |
| 2322 | /* close RAN conn */ |
| 2323 | if (cell->conn) { |
| 2324 | cell->conn->vgcs.cell = NULL; |
| 2325 | ran_conn_close(cell->conn); |
| 2326 | cell->conn = NULL; |
| 2327 | } |
| 2328 | |
| 2329 | /* Detach from BSS now. Check, to prevent race condition. */ |
| 2330 | if (cell->bss) { |
| 2331 | /* Remove pointer to talking channel. */ |
| 2332 | if (cell->bss->trans && cell->bss->trans->gcc.uplink_cell == cell) |
| 2333 | cell->bss->trans->gcc.uplink_cell = NULL; |
| 2334 | llist_del(&cell->list_bss); |
| 2335 | cell->bss = NULL; |
| 2336 | } |
| 2337 | |
| 2338 | /* Detach from MGW now. Check, to prevent race condition. */ |
| 2339 | if (cell->mgw) { |
| 2340 | mgw = cell->mgw; |
| 2341 | llist_del(&cell->list_mgw); |
| 2342 | cell->mgw = NULL; |
| 2343 | /* Destroy MGW endpoint, if list is empty. */ |
| 2344 | if (llist_empty(&mgw->cell_list)) |
| 2345 | osmo_fsm_inst_dispatch(mgw->fi, VGCS_MGW_EP_EV_CLEAR, NULL); |
| 2346 | } |
| 2347 | |
| 2348 | LOG_CELL(cell, LOGL_DEBUG, "Detroy connection to cell.\n"); |
| 2349 | |
| 2350 | /* Free FSM. (should be allocated) */ |
| 2351 | osmo_fsm_inst_state_chg(cell->fi, VGCS_CELL_ST_NULL, 0, 0); |
| 2352 | osmo_fsm_inst_term(cell->fi, OSMO_FSM_TERM_REGULAR, NULL); |
| 2353 | } |
| 2354 | |
| 2355 | static void vgcs_cell_fsm_null(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 2356 | { |
| 2357 | struct vgcs_bss_cell *cell = fi->priv; |
| 2358 | const struct codec_mapping *cm; |
| 2359 | int rc; |
| 2360 | |
| 2361 | switch (event) { |
| 2362 | case VGCS_CELL_EV_ASSIGN: |
| 2363 | LOG_CELL(cell, LOGL_DEBUG, "Received assignment from BSS controling process.\n"); |
| 2364 | /* Allocate rtps stream. */ |
| 2365 | cell->rtps = rtp_stream_alloc(cell->fi, VGCS_CELL_EV_RTP_STREAM_GONE, |
| 2366 | VGCS_CELL_EV_RTP_STREAM_ADDR_AVAILABLE, |
| 2367 | VGCS_CELL_EV_RTP_STREAM_ESTABLISHED, RTP_TO_RAN, cell->call_id, |
| 2368 | NULL); |
| 2369 | if (!cell->rtps) { |
| 2370 | LOG_CELL(cell, LOGL_DEBUG, "Failed to allocate RTP stream, cannot continue.\n"); |
| 2371 | cell_destroy(cell); |
| 2372 | break; |
| 2373 | } |
| 2374 | /* Hard coded codec: GSM V1 */ |
| 2375 | cm = codec_mapping_by_gsm0808_speech_codec_type(GSM0808_SCT_FR1); |
Andreas Eversberg | 33a433a | 2023-07-19 10:01:20 +0200 | [diff] [blame] | 2376 | if (!cm) { |
| 2377 | LOG_CELL(cell, LOGL_DEBUG, "Selected codec not supported, cannot continue.\n"); |
| 2378 | cell_clear(cell, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC); |
| 2379 | break; |
| 2380 | } |
Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 2381 | rtp_stream_set_one_codec(cell->rtps, &cm->sdp); |
| 2382 | /* Set initial mode. */ |
| 2383 | rtp_stream_set_mode(cell->rtps, MGCP_CONN_RECV_ONLY); |
| 2384 | /* Commit RTP stream. */ |
Andreas Eversberg | d637760 | 2023-07-19 09:46:18 +0200 | [diff] [blame] | 2385 | if (!cell->bss || !cell->bss->trans) { |
| 2386 | LOG_CELL(cell, LOGL_DEBUG, "No BSS/transaction, cannot continue.\n"); |
Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 2387 | cell_clear(cell, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC); |
| 2388 | break; |
| 2389 | } |
Andreas Eversberg | d637760 | 2023-07-19 09:46:18 +0200 | [diff] [blame] | 2390 | if (!cell->mgw || !cell->mgw->mgw_ep) { |
Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 2391 | LOG_CELL(cell, LOGL_DEBUG, "No MGW endpoint, cannot continue.\n"); |
| 2392 | cell_clear(cell, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC); |
| 2393 | break; |
| 2394 | } |
| 2395 | rc = rtp_stream_ensure_ci(cell->rtps, cell->mgw->mgw_ep); |
| 2396 | if (rc < 0) { |
| 2397 | LOG_CELL(cell, LOGL_DEBUG, "Failed to trigger RTP stream CI.\n"); |
| 2398 | cell_clear(cell, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC); |
| 2399 | break; |
| 2400 | } |
| 2401 | /* Change state. */ |
| 2402 | osmo_fsm_inst_state_chg(fi, VGCS_CELL_ST_ASSIGNMENT, 0, 0); |
| 2403 | break; |
| 2404 | case VGCS_CELL_EV_CLEAR: |
| 2405 | /* The calling user process requested clearing of VGCS/VBS call. */ |
| 2406 | LOG_CELL(cell, LOGL_DEBUG, "Received clearing from BSS controling process.\n"); |
| 2407 | cell_clear(cell, GSM0808_CAUSE_CALL_CONTROL); |
| 2408 | break; |
| 2409 | default: |
| 2410 | OSMO_ASSERT(false); |
| 2411 | } |
| 2412 | } |
| 2413 | |
| 2414 | static void vgcs_cell_fsm_assignment(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 2415 | { |
| 2416 | struct vgcs_bss_cell *cell = fi->priv; |
| 2417 | struct ran_msg *rx_ran_msg = data; |
| 2418 | struct ran_msg tx_ran_msg; |
| 2419 | struct osmo_sockaddr_str ss; |
| 2420 | const struct codec_mapping *cm; |
| 2421 | struct vgcs_bss *bss; |
| 2422 | int rc; |
| 2423 | |
| 2424 | switch (event) { |
| 2425 | case VGCS_CELL_EV_RTP_STREAM_GONE: |
| 2426 | /* The RTP stream failed. */ |
| 2427 | LOG_CELL(cell, LOGL_ERROR, "RTP stream of MGW failed.\n"); |
| 2428 | cell->rtps = NULL; |
| 2429 | goto channel_fail; |
| 2430 | break; |
| 2431 | case VGCS_CELL_EV_RTP_STREAM_ADDR_AVAILABLE: |
| 2432 | /* The RTP stream sends its peer. */ |
| 2433 | if (!osmo_sockaddr_str_is_nonzero(&cell->rtps->local)) { |
| 2434 | LOG_CELL(cell, LOGL_ERROR, "Invalid RTP address received from MGW: " OSMO_SOCKADDR_STR_FMT "\n", |
| 2435 | OSMO_SOCKADDR_STR_FMT_ARGS(&cell->rtps->local)); |
| 2436 | goto channel_fail; |
| 2437 | } |
| 2438 | LOG_CELL(cell, LOGL_DEBUG, |
| 2439 | "MGW endpoint's RTP address available for the CI %s: " OSMO_SOCKADDR_STR_FMT " (osmux=%s:%d)\n", |
| 2440 | rtp_direction_name(cell->rtps->dir), OSMO_SOCKADDR_STR_FMT_ARGS(&cell->rtps->local), |
| 2441 | cell->rtps->use_osmux ? "yes" : "no", cell->rtps->local_osmux_cid); |
| 2442 | /* Send VGCS/VBS ASSIGNMENT REQUEST to BSS */ |
| 2443 | LOG_CELL(cell, LOGL_DEBUG, "Sending VGCS/VBS ASSIGNMENT REQUEST towards BSS.\n"); |
| 2444 | tx_ran_msg = (struct ran_msg) { |
| 2445 | .msg_type = RAN_MSG_VGCS_VBS_ASSIGN_REQ, |
| 2446 | .vgcs_vbs_assign_req = { |
| 2447 | /* For now we support GSM/FR V1 only. This shall be supported by all MS. */ |
| 2448 | .channel_type = { |
| 2449 | .ch_indctr = GSM0808_CHAN_SPEECH, |
| 2450 | .ch_rate_type = GSM0808_SPEECH_FULL_BM, |
| 2451 | .perm_spch_len = 1, |
| 2452 | .perm_spch[0] = GSM0808_PERM_FR1, |
| 2453 | }, |
| 2454 | /* For now we want a channel without any delay. */ |
| 2455 | .ass_req = GSM0808_ASRQ_IMMEDIATE, |
| 2456 | .callref = { |
| 2457 | .sf = (cell->trans_type == TRANS_GCC), |
| 2458 | }, |
| 2459 | /* We need to identify the cell only. */ |
| 2460 | .cell_identifier = { |
| 2461 | .id_discr = CELL_IDENT_CI, |
| 2462 | .id.ci = cell->cell_id, |
| 2463 | }, |
| 2464 | .aoip_transport_layer_present = true, |
| 2465 | .call_id_present = true, |
| 2466 | .call_id = cell->call_id, |
| 2467 | .codec_list_present = true, |
| 2468 | .codec_list_msc_preferred = { |
| 2469 | .len = 1, |
| 2470 | .codec[0] = { |
| 2471 | .fi = 1, |
| 2472 | .type = GSM0808_SCT_FR1, |
| 2473 | .cfg = 0, |
| 2474 | }, |
| 2475 | }, |
| 2476 | }, |
| 2477 | }; |
| 2478 | osmo_store32be_ext(cell->callref >> 3, &tx_ran_msg.vgcs_vbs_assign_req.callref.call_ref_hi, 3); |
| 2479 | tx_ran_msg.vgcs_vbs_assign_req.callref.call_ref_lo = cell->callref & 0x7; |
| 2480 | osmo_sockaddr_str_to_sockaddr(&cell->rtps->local, &tx_ran_msg.vgcs_vbs_assign_req.aoip_transport_layer); |
| 2481 | /* First message, so we must set "initial" to "true". */ |
| 2482 | ran_encode_and_send(fi, &tx_ran_msg, cell->conn, true); |
| 2483 | break; |
| 2484 | case VGCS_CELL_EV_RTP_STREAM_ESTABLISHED: |
| 2485 | /* The RTP stream established. */ |
| 2486 | LOG_CELL(cell, LOGL_DEBUG, "RTP stream is established.\n"); |
| 2487 | break; |
| 2488 | case VGCS_CELL_EV_ASSIGN_RES: |
| 2489 | /* Receive VGCS/VBS ASSIGNMENT RESULT from BSS. */ |
| 2490 | LOG_CELL(cell, LOGL_DEBUG, "Received VGCS/VBS ASSIGNMENT RESULT from BSS.\n"); |
| 2491 | cell->assigned = true; |
| 2492 | if (!rx_ran_msg->vgcs_vbs_assign_res.aoip_transport_layer_present |
| 2493 | && !rx_ran_msg->vgcs_vbs_assign_res.codec_present |
| 2494 | && !rx_ran_msg->vgcs_vbs_assign_res.call_id_present) { |
| 2495 | LOG_CELL(cell, LOGL_ERROR, "Mandatory IEs missing.\n"); |
| 2496 | goto channel_fail; |
| 2497 | } |
| 2498 | /* Send remote peer to RTP stream. */ |
| 2499 | if (osmo_sockaddr_str_from_sockaddr(&ss, &rx_ran_msg->vgcs_vbs_assign_res.aoip_transport_layer)) { |
| 2500 | LOG_CELL(cell, LOGL_ERROR, "Cannot RTP-CONNECT, invalid RTP IP:port in incoming MNCC " |
| 2501 | "message\n"); |
| 2502 | goto channel_fail; |
| 2503 | } |
| 2504 | rtp_stream_set_remote_addr(cell->rtps, &ss); |
| 2505 | /* Send remote codec to RTP stream. */ |
| 2506 | cm = codec_mapping_by_gsm0808_speech_codec_type(rx_ran_msg->vgcs_vbs_assign_res.codec_msc_chosen.type); |
| 2507 | if (!cm) { |
| 2508 | LOG_CELL(cell, LOGL_ERROR, "Chosen codec by BSC is not supported by MSC.\n"); |
| 2509 | goto channel_fail; |
| 2510 | } |
| 2511 | rtp_stream_set_one_codec(cell->rtps, &cm->sdp); |
| 2512 | /* Set listening mode. */ |
| 2513 | rtp_stream_set_mode(cell->rtps, MGCP_CONN_SEND_ONLY); |
| 2514 | /* Commit RTP stream. */ |
| 2515 | rc = rtp_stream_commit(cell->rtps); |
| 2516 | if (rc < 0) { |
| 2517 | LOG_CELL(cell, LOGL_ERROR, "Failed to commit parameters to RTP stream.\n"); |
| 2518 | goto channel_fail; |
| 2519 | } |
| 2520 | /* Change state. */ |
| 2521 | osmo_fsm_inst_state_chg(fi, VGCS_CELL_ST_ACTIVE, 0, 0); |
| 2522 | /* Notify BSS FSM about channel activation. */ |
| 2523 | if (cell->bss) |
| 2524 | osmo_fsm_inst_dispatch(cell->bss->fi, VGCS_BSS_EV_ACTIVE_OR_FAIL, NULL); |
| 2525 | break; |
| 2526 | case VGCS_CELL_EV_ASSIGN_FAIL: |
| 2527 | /* Received VGCS/VBS ASSIGNMENT FAILURE from BSS. */ |
| 2528 | LOG_CELL(cell, LOGL_NOTICE, "Received VGCS/VBS ASSIGNMENT FAILURE from BSS.\n"); |
| 2529 | channel_fail: |
| 2530 | bss = cell->bss; |
Andreas Eversberg | e24636c | 2023-04-23 12:20:55 +0200 | [diff] [blame] | 2531 | cell_clear(cell, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC); |
| 2532 | /* Notify BSS FSM about channel failure. */ |
| 2533 | if (bss) |
| 2534 | osmo_fsm_inst_dispatch(bss->fi, VGCS_BSS_EV_ACTIVE_OR_FAIL, NULL); |
| 2535 | break; |
| 2536 | case VGCS_CELL_EV_CLEAR: |
| 2537 | /* The calling user process requested clearing of VGCS/VBS call. */ |
| 2538 | LOG_CELL(cell, LOGL_DEBUG, "Received clearing from BSS controling process.\n"); |
| 2539 | cell_clear(cell, GSM0808_CAUSE_CALL_CONTROL); |
| 2540 | break; |
| 2541 | case VGCS_CELL_EV_CLOSE: |
| 2542 | /* The SCCP connection from the MSC has been closed. */ |
| 2543 | LOG_CELL(cell, LOGL_NOTICE, "Received SCCP connecting closing from MSC.\n"); |
| 2544 | if (cell->conn) { |
| 2545 | cell->conn->vgcs.bss = NULL; |
| 2546 | cell->conn = NULL; |
| 2547 | } |
| 2548 | cell_clear(cell, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC); |
| 2549 | break; |
| 2550 | default: |
| 2551 | OSMO_ASSERT(false); |
| 2552 | } |
| 2553 | } |
| 2554 | |
| 2555 | static void vgcs_cell_fsm_active(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 2556 | { |
| 2557 | struct vgcs_bss_cell *cell = fi->priv; |
| 2558 | |
| 2559 | switch (event) { |
| 2560 | case VGCS_CELL_EV_RTP_STREAM_GONE: |
| 2561 | /* The RTP stream failed. */ |
| 2562 | LOG_CELL(cell, LOGL_ERROR, "RTP stream of MGW failed.\n"); |
| 2563 | cell->rtps = NULL; |
| 2564 | cell_clear(cell, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC); |
| 2565 | break; |
| 2566 | case VGCS_CELL_EV_RTP_STREAM_ESTABLISHED: |
| 2567 | /* The RTP stream established. */ |
| 2568 | LOG_CELL(cell, LOGL_DEBUG, "RTP stream is established.\n"); |
| 2569 | break; |
| 2570 | case VGCS_CELL_EV_CLEAR: |
| 2571 | /* The calling user process requested clearing of VGCS/VBS call. */ |
| 2572 | LOG_CELL(cell, LOGL_DEBUG, "Received clearing from BSS controling process.\n"); |
| 2573 | cell_clear(cell, GSM0808_CAUSE_CALL_CONTROL); |
| 2574 | break; |
| 2575 | case VGCS_CELL_EV_CLOSE: |
| 2576 | /* The SCCP connection from the MSC has been closed. */ |
| 2577 | LOG_CELL(cell, LOGL_NOTICE, "Received SCCP connecting closing from MSC.\n"); |
| 2578 | if (cell->conn) { |
| 2579 | cell->conn->vgcs.bss = NULL; |
| 2580 | cell->conn = NULL; |
| 2581 | } |
| 2582 | cell_clear(cell, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC); |
| 2583 | break; |
| 2584 | default: |
| 2585 | OSMO_ASSERT(false); |
| 2586 | } |
| 2587 | } |
| 2588 | |
| 2589 | static void vgcs_cell_fsm_release(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 2590 | { |
| 2591 | struct vgcs_bss_cell *cell = fi->priv; |
| 2592 | |
| 2593 | switch (event) { |
| 2594 | case VGCS_CELL_EV_RTP_STREAM_GONE: |
| 2595 | /* The RTP stream gone. */ |
| 2596 | LOG_CELL(cell, LOGL_ERROR, "RTP stream gone.\n"); |
| 2597 | cell->rtps = NULL; |
| 2598 | /* Wait for RAN conn. */ |
| 2599 | if (cell->conn) |
| 2600 | break; |
| 2601 | cell_destroy(cell); |
| 2602 | break; |
| 2603 | case VGCS_CELL_EV_CLEAR: |
| 2604 | case VGCS_CELL_EV_RELEASED: |
| 2605 | if (event == VGCS_CELL_EV_CLEAR) { |
| 2606 | /* The SCCP connection from the MSC has been closed while waiting for CLEAR COMPLETE. */ |
| 2607 | LOG_CELL(cell, LOGL_NOTICE, "Received SCCP closing collision.\n"); |
| 2608 | } else |
| 2609 | LOG_CELL(cell, LOGL_DEBUG, "Received CLEAR COMPLETE from BSS, we are done!\n"); |
| 2610 | /* Wait for RTP stream. */ |
| 2611 | if (cell->rtps) { |
| 2612 | /* close RAN conn */ |
| 2613 | if (cell->conn) { |
| 2614 | cell->conn->vgcs.cell = NULL; |
| 2615 | ran_conn_close(cell->conn); |
| 2616 | cell->conn = NULL; |
| 2617 | } |
| 2618 | break; |
| 2619 | } |
| 2620 | cell_destroy(cell); |
| 2621 | break; |
| 2622 | default: |
| 2623 | OSMO_ASSERT(false); |
| 2624 | } |
| 2625 | } |
| 2626 | |
| 2627 | static const struct osmo_fsm_state vgcs_cell_fsm_states[] = { |
| 2628 | [VGCS_CELL_ST_NULL] = { |
| 2629 | .name = "NULL", |
| 2630 | .in_event_mask = S(VGCS_CELL_EV_ASSIGN) | |
| 2631 | S(VGCS_CELL_EV_CLEAR), |
| 2632 | .out_state_mask = S(VGCS_CELL_ST_ASSIGNMENT), |
| 2633 | .action = vgcs_cell_fsm_null, |
| 2634 | }, |
| 2635 | [VGCS_CELL_ST_ASSIGNMENT] = { |
| 2636 | .name = "ASSIGNMENT Sent", |
| 2637 | .in_event_mask = S(VGCS_CELL_EV_RTP_STREAM_GONE) | |
| 2638 | S(VGCS_CELL_EV_RTP_STREAM_ADDR_AVAILABLE) | |
| 2639 | S(VGCS_CELL_EV_RTP_STREAM_ESTABLISHED) | |
| 2640 | S(VGCS_CELL_EV_ASSIGN_RES) | |
| 2641 | S(VGCS_CELL_EV_ASSIGN_FAIL) | |
| 2642 | S(VGCS_CELL_EV_CLEAR) | |
| 2643 | S(VGCS_CELL_EV_CLOSE), |
| 2644 | .out_state_mask = S(VGCS_CELL_ST_ACTIVE) | |
| 2645 | S(VGCS_CELL_ST_RELEASE), |
| 2646 | .action = vgcs_cell_fsm_assignment, |
| 2647 | }, |
| 2648 | [VGCS_CELL_ST_ACTIVE] = { |
| 2649 | .name = "VGCS/VBS channel active", |
| 2650 | .in_event_mask = S(VGCS_CELL_EV_RTP_STREAM_GONE) | |
| 2651 | S(VGCS_CELL_EV_RTP_STREAM_ESTABLISHED) | |
| 2652 | S(VGCS_CELL_EV_CLEAR) | |
| 2653 | S(VGCS_CELL_EV_CLOSE), |
| 2654 | .out_state_mask = S(VGCS_CELL_ST_RELEASE), |
| 2655 | .action = vgcs_cell_fsm_active, |
| 2656 | }, |
| 2657 | [VGCS_CELL_ST_RELEASE] = { |
| 2658 | .name = "Releasing VGCS/VBS channel", |
| 2659 | .in_event_mask = S(VGCS_CELL_EV_RTP_STREAM_GONE) | |
| 2660 | S(VGCS_CELL_EV_CLEAR) | |
| 2661 | S(VGCS_CELL_EV_RELEASED), |
| 2662 | .out_state_mask = S(VGCS_CELL_ST_NULL), |
| 2663 | .action = vgcs_cell_fsm_release, |
| 2664 | }, |
| 2665 | }; |
| 2666 | |
| 2667 | static struct osmo_fsm vgcs_cell_fsm = { |
| 2668 | .name = "vgcs_cell", |
| 2669 | .states = vgcs_cell_fsm_states, |
| 2670 | .num_states = ARRAY_SIZE(vgcs_cell_fsm_states), |
| 2671 | .log_subsys = DASCI, |
| 2672 | .event_names = vgcs_cell_fsm_event_names, |
| 2673 | }; |
| 2674 | |
| 2675 | /* The BSS accepts VGCS/VBS channel assignment. */ |
| 2676 | void vgcs_vbs_assign_result(struct vgcs_bss_cell *cell, const struct ran_msg *ran_msg) |
| 2677 | { |
| 2678 | osmo_fsm_inst_dispatch(cell->fi, VGCS_CELL_EV_ASSIGN_RES, (void *)ran_msg); |
| 2679 | } |
| 2680 | |
| 2681 | /* The BSS refuses VGCS/VBS channel assignment. */ |
| 2682 | void vgcs_vbs_assign_fail(struct vgcs_bss_cell *cell, const struct ran_msg *ran_msg) |
| 2683 | { |
| 2684 | osmo_fsm_inst_dispatch(cell->fi, VGCS_CELL_EV_ASSIGN_FAIL, (void *)ran_msg); |
| 2685 | } |
| 2686 | |
| 2687 | /* BSS indicated that the channel has been released. */ |
| 2688 | void vgcs_vbs_clear_req_channel(struct vgcs_bss_cell *cell, const struct ran_msg *ran_msg) |
| 2689 | { |
| 2690 | LOG_CELL(cell, LOGL_DEBUG, "Received CLEAR REQUEST for resource controling channel from BSS.\n"); |
| 2691 | osmo_fsm_inst_dispatch(cell->fi, VGCS_CELL_EV_CLOSE, (void *)ran_msg); |
| 2692 | } |
| 2693 | |
| 2694 | /* BSS confirms the release of channel. */ |
| 2695 | void vgcs_vbs_clear_cpl_channel(struct vgcs_bss_cell *cell, const struct ran_msg *ran_msg) |
| 2696 | { |
| 2697 | LOG_CELL(cell, LOGL_DEBUG, "Received CLEAR COMPLETE for resource controling channel from BSS.\n"); |
| 2698 | osmo_fsm_inst_dispatch(cell->fi, VGCS_CELL_EV_RELEASED, (void *)ran_msg); |
| 2699 | } |
| 2700 | |
| 2701 | /* |
| 2702 | * MGW endpoint FSM |
| 2703 | */ |
| 2704 | |
| 2705 | static const struct value_string vgcs_mgw_ep_fsm_event_names[] = { |
| 2706 | OSMO_VALUE_STRING(VGCS_MGW_EP_EV_FREE), |
| 2707 | OSMO_VALUE_STRING(VGCS_MGW_EP_EV_CLEAR), |
| 2708 | { } |
| 2709 | }; |
| 2710 | |
| 2711 | static void vgcs_mgw_ep_fsm_active(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 2712 | { |
| 2713 | struct vgcs_mgw_ep *mgw = fi->priv; |
| 2714 | struct vgcs_bss_cell *cell, *cell2; |
| 2715 | struct mgcp_client *mgcp_client; |
| 2716 | |
| 2717 | switch (event) { |
| 2718 | case VGCS_MGW_EP_EV_FREE: |
| 2719 | LOGP(DASCI, LOGL_DEBUG, "MGW connection closed, removing all cell instances.\n"); |
| 2720 | llist_for_each_entry_safe(cell, cell2, &mgw->cell_list, list_mgw) { |
| 2721 | if (cell->rtps) |
| 2722 | cell->rtps->ci = NULL; |
| 2723 | llist_del(&cell->list_mgw); |
| 2724 | cell->mgw = NULL; |
| 2725 | } |
| 2726 | /* Put MGCP client back into MGW pool. */ |
| 2727 | mgcp_client = osmo_mgcpc_ep_client(mgw->mgw_ep); |
| 2728 | mgcp_client_pool_put(mgcp_client); |
| 2729 | /* Destroy this instance. */ |
| 2730 | osmo_fsm_inst_term_children(fi, OSMO_FSM_TERM_PARENT, NULL); |
| 2731 | osmo_fsm_inst_term(fi, OSMO_FSM_TERM_REGULAR, NULL); |
| 2732 | break; |
| 2733 | case VGCS_MGW_EP_EV_CLEAR: |
| 2734 | if (!llist_empty(&mgw->cell_list)) |
| 2735 | break; |
| 2736 | LOGP(DASCI, LOGL_DEBUG, "Cell list of MGW instance is now empty, dropping.\n"); |
| 2737 | /* Destroy this instance. */ |
| 2738 | osmo_fsm_inst_term_children(fi, OSMO_FSM_TERM_PARENT, NULL); |
| 2739 | osmo_fsm_inst_term(fi, OSMO_FSM_TERM_REGULAR, NULL); |
| 2740 | break; |
| 2741 | default: |
| 2742 | OSMO_ASSERT(false); |
| 2743 | } |
| 2744 | } |
| 2745 | |
| 2746 | static const struct osmo_fsm_state vgcs_mgw_ep_fsm_states[] = { |
| 2747 | [VGCS_MGW_EP_ST_NULL] = { |
| 2748 | .name = "NULL", |
| 2749 | .out_state_mask = S(VGCS_MGW_EP_ST_ACTIVE), |
| 2750 | }, |
| 2751 | [VGCS_MGW_EP_ST_ACTIVE] = { |
| 2752 | .name = "MGW endpoint allocated", |
| 2753 | .in_event_mask = S(VGCS_MGW_EP_EV_FREE) | |
| 2754 | S(VGCS_MGW_EP_EV_CLEAR), |
| 2755 | .out_state_mask = S(VGCS_MGW_EP_ST_NULL), |
| 2756 | .action = vgcs_mgw_ep_fsm_active, |
| 2757 | }, |
| 2758 | }; |
| 2759 | |
| 2760 | static struct osmo_fsm vgcs_mgw_ep_fsm = { |
| 2761 | .name = "vgcs_mgw_ep", |
| 2762 | .states = vgcs_mgw_ep_fsm_states, |
| 2763 | .num_states = ARRAY_SIZE(vgcs_mgw_ep_fsm_states), |
| 2764 | .log_subsys = DASCI, |
| 2765 | .event_names = vgcs_mgw_ep_fsm_event_names, |
| 2766 | }; |