Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 1 | /* (C) 2017 by Harald Welte <laforge@gnumonks.org> |
| 2 | * All Rights Reserved |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU Affero General Public License as published by |
| 6 | * the Free Software Foundation; either version 3 of the License, or |
| 7 | * (at your option) any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | * GNU Affero General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU Affero General Public License |
| 15 | * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 16 | * |
| 17 | */ |
| 18 | |
| 19 | #include <osmocom/core/fsm.h> |
| 20 | #include <osmocom/core/logging.h> |
| 21 | #include <osmocom/gsm/gsm0808.h> |
| 22 | #include <osmocom/sigtran/sccp_sap.h> |
| 23 | #include <osmocom/gsm/gsm0808_utils.h> |
| 24 | |
| 25 | #include <osmocom/bsc/debug.h> |
| 26 | #include <osmocom/bsc/bsc_api.h> |
| 27 | #include <osmocom/bsc/gsm_data.h> |
| 28 | #include <osmocom/bsc/handover.h> |
| 29 | #include <osmocom/bsc/chan_alloc.h> |
| 30 | #include <osmocom/bsc/bsc_subscriber.h> |
| 31 | #include <osmocom/bsc/osmo_bsc_sigtran.h> |
| 32 | #include <osmocom/bsc/bsc_subscr_conn_fsm.h> |
| 33 | #include <osmocom/bsc/osmo_bsc.h> |
| 34 | #include <osmocom/bsc/penalty_timers.h> |
| 35 | #include <osmocom/mgcp_client/mgcp_client_fsm.h> |
| 36 | #include <osmocom/core/byteswap.h> |
| 37 | |
| 38 | #define S(x) (1 << (x)) |
| 39 | |
| 40 | #define MGCP_MGW_TIMEOUT 4 /* in seconds */ |
| 41 | #define MGCP_MGW_TIMEOUT_TIMER_NR 1 |
| 42 | |
| 43 | #define MGCP_MGW_HO_TIMEOUT 4 /* in seconds */ |
| 44 | #define MGCP_MGW_HO_TIMEOUT_TIMER_NR 2 |
| 45 | |
| 46 | #define GSM0808_T10_TIMER_NR 10 |
| 47 | #define GSM0808_T10_VALUE 6 |
| 48 | |
| 49 | #define ENDPOINT_ID "rtpbridge/*@mgw" |
| 50 | |
| 51 | enum gscon_fsm_states { |
| 52 | ST_INIT, |
| 53 | /* waiting for CC from MSC */ |
| 54 | ST_WAIT_CC, |
| 55 | /* active connection */ |
| 56 | ST_ACTIVE, |
| 57 | /* during assignment; waiting for ASS_CMPL */ |
| 58 | ST_WAIT_ASS_CMPL, |
| 59 | /* during assignment; waiting for MODE_MODIFY_ACK */ |
| 60 | ST_WAIT_MODE_MODIFY_ACK, |
| 61 | /* BSSMAP CLEAR has been received */ |
| 62 | ST_CLEARING, |
| 63 | |
| 64 | /* MGW handling */ |
| 65 | /* during assignment; waiting for MGW response to CRCX for BTS */ |
| 66 | ST_WAIT_CRCX_BTS, |
| 67 | /* during assignment; waiting for MGW response to MDCX for BTS */ |
| 68 | ST_WAIT_MDCX_BTS, |
| 69 | /* during assignment; waiting for MGW response to CRCX for MSC */ |
| 70 | ST_WAIT_CRCX_MSC, |
| 71 | |
| 72 | /* MT (inbound) handover */ |
| 73 | /* Wait for Handover Access from MS/BTS */ |
| 74 | ST_WAIT_MT_HO_ACC, |
| 75 | /* Wait for RR Handover Complete from MS/BTS */ |
| 76 | ST_WAIT_MT_HO_COMPL, |
| 77 | |
| 78 | /* MO (outbound) handover */ |
| 79 | /* Wait for Handover Command / Handover Required Reject from MSC */ |
| 80 | ST_WAIT_MO_HO_CMD, |
| 81 | /* Wait for Clear Command from MSC */ |
| 82 | ST_MO_HO_PROCEEDING, |
| 83 | |
| 84 | /* Internal HO handling */ |
| 85 | /* Wait for the handover logic to complete the handover */ |
| 86 | ST_WAIT_HO_COMPL, |
| 87 | /* during handover; waiting for MGW response to MDCX for BTS */ |
| 88 | ST_WAIT_MDCX_BTS_HO, |
| 89 | }; |
| 90 | |
| 91 | static const struct value_string gscon_fsm_event_names[] = { |
| 92 | {GSCON_EV_A_CONN_IND, "MT-CONNECT.ind"}, |
| 93 | {GSCON_EV_A_CONN_REQ, "MO-CONNECT.req"}, |
| 94 | {GSCON_EV_A_CONN_CFM, "MO-CONNECT.cfm"}, |
| 95 | {GSCON_EV_A_ASSIGNMENT_CMD, "ASSIGNMENT_CMD"}, |
| 96 | {GSCON_EV_A_CLEAR_CMD, "CLEAR_CMD"}, |
| 97 | {GSCON_EV_A_DISC_IND, "DISCONNET.ind"}, |
| 98 | {GSCON_EV_A_HO_REQ, "HANDOVER_REQUEST"}, |
| 99 | |
| 100 | {GSCON_EV_RR_ASS_COMPL, "RR_ASSIGN_COMPL"}, |
| 101 | {GSCON_EV_RR_ASS_FAIL, "RR_ASSIGN_FAIL"}, |
| 102 | {GSCON_EV_RR_MODE_MODIFY_ACK, "RR_MODE_MODIFY_ACK"}, |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 103 | {GSCON_EV_RLL_REL_IND, "RLL_RELEASE.ind"}, |
| 104 | {GSCON_EV_RSL_CONN_FAIL, "RSL_CONN_FAIL.ind"}, |
| 105 | {GSCON_EV_RSL_CLEAR_COMPL, "RSL_CLEAR_COMPLETE"}, |
| 106 | |
| 107 | {GSCON_EV_MO_DTAP, "MO-DTAP"}, |
| 108 | {GSCON_EV_MT_DTAP, "MT-DTAP"}, |
| 109 | {GSCON_EV_TX_SCCP, "TX_SCCP"}, |
| 110 | |
| 111 | {GSCON_EV_MGW_FAIL_BTS, "MGW_FAILURE_BTS"}, |
| 112 | {GSCON_EV_MGW_FAIL_MSC, "MGW_FAILURE_MSC"}, |
| 113 | {GSCON_EV_MGW_CRCX_RESP_BTS, "MGW_CRCX_RESPONSE_BTS"}, |
| 114 | {GSCON_EV_MGW_MDCX_RESP_BTS, "MGW_MDCX_RESPONSE_BTS"}, |
| 115 | {GSCON_EV_MGW_CRCX_RESP_MSC, "MGW_CRCX_RESPONSE_MSC"}, |
| 116 | |
| 117 | {GSCON_EV_HO_START, "HO_START"}, |
| 118 | {GSCON_EV_HO_TIMEOUT, "HO_TIMEOUT"}, |
| 119 | {GSCON_EV_HO_FAIL, "HO_FAIL"}, |
| 120 | {GSCON_EV_HO_COMPL, "HO_COMPL"}, |
| 121 | |
| 122 | {0, NULL} |
| 123 | }; |
| 124 | |
| 125 | /* Send data SCCP message through SCCP connection. All sigtran messages |
| 126 | * that are send from this FSM must use this function. Never use |
| 127 | * osmo_bsc_sigtran_send() directly since this would defeat the checks |
| 128 | * provided by this function. */ |
| 129 | static void sigtran_send(struct gsm_subscriber_connection *conn, struct msgb *msg, struct osmo_fsm_inst *fi) |
| 130 | { |
| 131 | int rc; |
| 132 | |
| 133 | /* Make sure that we only attempt to send SCCP messages if we have |
| 134 | * a life SCCP connection. Otherwise drop the message. */ |
| 135 | if (fi->state == ST_INIT || fi->state == ST_WAIT_CC) { |
| 136 | LOGPFSML(fi, LOGL_ERROR, "No active SCCP connection, dropping message!\n"); |
| 137 | msgb_free(msg); |
| 138 | return; |
| 139 | } |
| 140 | |
| 141 | rc = osmo_bsc_sigtran_send(conn, msg); |
| 142 | if (rc < 0) |
| 143 | LOGPFSML(fi, LOGL_ERROR, "Unable to deliver SCCP message!\n"); |
| 144 | } |
| 145 | |
Harald Welte | ead291a | 2018-03-21 22:11:32 +0100 | [diff] [blame] | 146 | |
| 147 | /* See TS 48.008 3.2.2.11 Channel Type Octet 5 */ |
| 148 | static int bssap_speech_from_lchan(const struct gsm_lchan *lchan) |
| 149 | { |
| 150 | switch (lchan->type) { |
| 151 | case GSM_LCHAN_TCH_H: |
| 152 | switch (lchan->tch_mode) { |
| 153 | case GSM48_CMODE_SPEECH_V1: |
| 154 | return 0x05; |
| 155 | case GSM48_CMODE_SPEECH_AMR: |
| 156 | return 0x25; |
| 157 | default: |
| 158 | return -1; |
| 159 | } |
| 160 | break; |
| 161 | case GSM_LCHAN_TCH_F: |
| 162 | switch (lchan->tch_mode) { |
| 163 | case GSM48_CMODE_SPEECH_V1: |
| 164 | return 0x01; |
| 165 | case GSM48_CMODE_SPEECH_EFR: |
| 166 | return 0x11; |
| 167 | case GSM48_CMODE_SPEECH_AMR: |
| 168 | return 0x21; |
| 169 | default: |
| 170 | return -1; |
| 171 | } |
| 172 | break; |
| 173 | default: |
| 174 | return -1; |
| 175 | } |
| 176 | } |
| 177 | |
| 178 | /* GSM 08.08 3.2.2.33 */ |
| 179 | static uint8_t lchan_to_chosen_channel(struct gsm_lchan *lchan) |
| 180 | { |
| 181 | uint8_t channel_mode = 0, channel = 0; |
| 182 | |
| 183 | switch (lchan->tch_mode) { |
| 184 | case GSM48_CMODE_SPEECH_V1: |
| 185 | case GSM48_CMODE_SPEECH_EFR: |
| 186 | case GSM48_CMODE_SPEECH_AMR: |
| 187 | channel_mode = 0x9; |
| 188 | break; |
| 189 | case GSM48_CMODE_SIGN: |
| 190 | channel_mode = 0x8; |
| 191 | break; |
| 192 | case GSM48_CMODE_DATA_14k5: |
| 193 | channel_mode = 0xe; |
| 194 | break; |
| 195 | case GSM48_CMODE_DATA_12k0: |
| 196 | channel_mode = 0xb; |
| 197 | break; |
| 198 | case GSM48_CMODE_DATA_6k0: |
| 199 | channel_mode = 0xc; |
| 200 | break; |
| 201 | case GSM48_CMODE_DATA_3k6: |
| 202 | channel_mode = 0xd; |
| 203 | break; |
| 204 | } |
| 205 | |
| 206 | switch (lchan->type) { |
| 207 | case GSM_LCHAN_NONE: |
| 208 | channel = 0x0; |
| 209 | break; |
| 210 | case GSM_LCHAN_SDCCH: |
| 211 | channel = 0x1; |
| 212 | break; |
| 213 | case GSM_LCHAN_TCH_F: |
| 214 | channel = 0x8; |
| 215 | break; |
| 216 | case GSM_LCHAN_TCH_H: |
| 217 | channel = 0x9; |
| 218 | break; |
| 219 | case GSM_LCHAN_UNKNOWN: |
| 220 | default: |
| 221 | LOGP(DMSC, LOGL_ERROR, "Unknown lchan type: %p\n", lchan); |
| 222 | break; |
| 223 | } |
| 224 | |
| 225 | return channel_mode << 4 | channel; |
| 226 | } |
| 227 | |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 228 | /* Generate and send assignment complete message */ |
| 229 | static void send_ass_compl(struct gsm_lchan *lchan, struct osmo_fsm_inst *fi) |
| 230 | { |
| 231 | struct msgb *resp; |
| 232 | struct gsm0808_speech_codec sc; |
| 233 | struct gsm_subscriber_connection *conn; |
Harald Welte | ead291a | 2018-03-21 22:11:32 +0100 | [diff] [blame] | 234 | int perm_spch = bssap_speech_from_lchan(lchan); |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 235 | |
| 236 | conn = lchan->conn; |
| 237 | |
| 238 | OSMO_ASSERT(lchan->abis_ip.ass_compl.valid); |
| 239 | OSMO_ASSERT(conn); |
| 240 | |
| 241 | LOGPFSML(fi, LOGL_DEBUG, "Sending assignment complete message... (id=%i)\n", conn->sccp.conn_id); |
| 242 | |
| 243 | /* Extrapolate speech codec from speech mode */ |
Harald Welte | ead291a | 2018-03-21 22:11:32 +0100 | [diff] [blame] | 244 | gsm0808_speech_codec_from_chan_type(&sc, perm_spch); |
| 245 | /* FIXME: AMR codec configuration must be derived from lchan1! */ |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 246 | |
| 247 | /* Generate message */ |
| 248 | resp = gsm0808_create_ass_compl(lchan->abis_ip.ass_compl.rr_cause, |
Harald Welte | ead291a | 2018-03-21 22:11:32 +0100 | [diff] [blame] | 249 | lchan_to_chosen_channel(lchan), |
| 250 | lchan->encr.alg_id, perm_spch, |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 251 | &conn->user_plane.aoip_rtp_addr_local, &sc, NULL); |
| 252 | |
| 253 | if (!resp) { |
| 254 | LOGPFSML(fi, LOGL_ERROR, "Failed to generate assignment completed message! (id=%i)\n", |
| 255 | conn->sccp.conn_id); |
| 256 | } |
| 257 | |
| 258 | sigtran_send(conn, resp, fi); |
| 259 | } |
| 260 | |
| 261 | /* forward MT DTAP from BSSAP side to RSL side */ |
| 262 | static void submit_dtap(struct gsm_subscriber_connection *conn, struct msgb *msg, struct osmo_fsm_inst *fi) |
| 263 | { |
| 264 | int rc; |
| 265 | struct msgb *resp = NULL; |
| 266 | |
| 267 | OSMO_ASSERT(fi); |
| 268 | OSMO_ASSERT(msg); |
| 269 | OSMO_ASSERT(conn); |
| 270 | |
| 271 | rc = gsm0808_submit_dtap(conn, msg, OBSC_LINKID_CB(msg), 1); |
| 272 | if (rc != 0) { |
| 273 | LOGPFSML(fi, LOGL_ERROR, "Tx BSSMAP CLEAR REQUEST to MSC\n"); |
| 274 | resp = gsm0808_create_clear_rqst(GSM0808_CAUSE_EQUIPMENT_FAILURE); |
| 275 | sigtran_send(conn, resp, fi); |
| 276 | osmo_fsm_inst_state_chg(fi, ST_ACTIVE, 0, 0); |
| 277 | return; |
| 278 | } |
| 279 | } |
| 280 | |
| 281 | /* forward MO DTAP from RSL side to BSSAP side */ |
Philipp Maier | 4be98dc | 2018-03-21 11:07:53 +0100 | [diff] [blame] | 282 | static void forward_dtap(struct gsm_subscriber_connection *conn, struct msgb *msg, struct osmo_fsm_inst *fi) |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 283 | { |
| 284 | struct msgb *resp = NULL; |
| 285 | |
| 286 | OSMO_ASSERT(msg); |
| 287 | OSMO_ASSERT(conn); |
| 288 | |
| 289 | resp = gsm0808_create_dtap(msg, OBSC_LINKID_CB(msg)); |
| 290 | sigtran_send(conn, resp, fi); |
| 291 | } |
| 292 | |
| 293 | /* In case there are open MGCP connections, toss |
| 294 | * those connections */ |
| 295 | static void toss_mgcp_conn(struct gsm_subscriber_connection *conn, struct osmo_fsm_inst *fi) |
| 296 | { |
| 297 | LOGPFSML(fi, LOGL_ERROR, "tossing all MGCP connections...\n"); |
| 298 | |
| 299 | if (conn->user_plane.fi_bts) { |
| 300 | mgcp_conn_delete(conn->user_plane.fi_bts); |
| 301 | conn->user_plane.fi_bts = NULL; |
| 302 | } |
| 303 | |
| 304 | if (conn->user_plane.fi_msc) { |
| 305 | mgcp_conn_delete(conn->user_plane.fi_msc); |
| 306 | conn->user_plane.fi_msc = NULL; |
| 307 | } |
| 308 | |
| 309 | if (conn->user_plane.mgw_endpoint) { |
| 310 | talloc_free(conn->user_plane.mgw_endpoint); |
| 311 | conn->user_plane.mgw_endpoint = NULL; |
| 312 | } |
| 313 | } |
| 314 | |
| 315 | static void gscon_fsm_init(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 316 | { |
| 317 | struct gsm_subscriber_connection *conn = fi->priv; |
| 318 | struct osmo_scu_prim *scu_prim = NULL; |
| 319 | struct msgb *msg = NULL; |
| 320 | int rc; |
| 321 | |
| 322 | switch (event) { |
| 323 | case GSCON_EV_A_CONN_REQ: |
| 324 | /* RLL ESTABLISH IND with initial L3 Message */ |
| 325 | msg = data; |
| 326 | /* FIXME: Extract Mobile ID and update FSM using osmo_fsm_inst_set_id() |
| 327 | * i.e. we will probably extract the mobile identity earlier, where the |
| 328 | * imsi filter code is. Then we could just use it here. |
| 329 | * related: OS#2969 */ |
| 330 | |
| 331 | rc = osmo_bsc_sigtran_open_conn(conn, msg); |
| 332 | if (rc < 0) { |
| 333 | osmo_fsm_inst_term(fi, OSMO_FSM_TERM_ERROR, NULL); |
| 334 | } else { |
| 335 | /* SCCP T(conn est) is 1-2 minutes, way too long. The MS will timeout |
| 336 | * using T3210 (20s), T3220 (5s) or T3230 (10s) */ |
| 337 | osmo_fsm_inst_state_chg(fi, ST_WAIT_CC, 20, 993210); |
| 338 | } |
| 339 | break; |
| 340 | case GSCON_EV_A_CONN_IND: |
| 341 | scu_prim = data; |
| 342 | if (!conn->sccp.msc) { |
| 343 | LOGPFSML(fi, LOGL_NOTICE, "N-CONNECT.ind from unknown MSC %s\n", |
| 344 | osmo_sccp_addr_dump(&scu_prim->u.connect.calling_addr)); |
| 345 | osmo_sccp_tx_disconn(conn->sccp.msc->a.sccp_user, scu_prim->u.connect.conn_id, |
| 346 | &scu_prim->u.connect.called_addr, 0); |
| 347 | osmo_fsm_inst_term(fi, OSMO_FSM_TERM_REGULAR, NULL); |
| 348 | } |
| 349 | /* FIXME: Extract optional IMSI and update FSM using osmo_fsm_inst_set_id() |
| 350 | * related: OS2969 (same as above) */ |
| 351 | |
| 352 | LOGPFSML(fi, LOGL_NOTICE, "No support for MSC-originated SCCP Connections yet\n"); |
| 353 | osmo_sccp_tx_disconn(conn->sccp.msc->a.sccp_user, scu_prim->u.connect.conn_id, |
| 354 | &scu_prim->u.connect.called_addr, 0); |
| 355 | osmo_fsm_inst_term(fi, OSMO_FSM_TERM_REGULAR, NULL); |
| 356 | break; |
| 357 | default: |
| 358 | OSMO_ASSERT(false); |
| 359 | break; |
| 360 | } |
| 361 | } |
| 362 | |
| 363 | /* We've sent the CONNECTION.req to the SCCP provider and are waiting for CC from MSC */ |
| 364 | static void gscon_fsm_wait_cc(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 365 | { |
| 366 | switch (event) { |
| 367 | case GSCON_EV_A_CONN_CFM: |
| 368 | /* MSC has confirmed the connection, we now change into the |
| 369 | * active state and wait there for further operations */ |
| 370 | osmo_fsm_inst_state_chg(fi, ST_ACTIVE, 0, 0); |
| 371 | /* if there's user payload, forward it just like EV_MT_DTAP */ |
| 372 | /* FIXME: Question: if there's user payload attached to the CC, forward it like EV_MT_DTAP? */ |
| 373 | break; |
| 374 | default: |
| 375 | OSMO_ASSERT(false); |
| 376 | break; |
| 377 | } |
| 378 | } |
| 379 | |
| 380 | /* We're on an active subscriber connection, passing DTAP back and forth */ |
| 381 | static void gscon_fsm_active(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 382 | { |
| 383 | struct gsm_subscriber_connection *conn = fi->priv; |
| 384 | struct msgb *resp = NULL; |
| 385 | struct mgcp_conn_peer conn_peer; |
| 386 | int rc; |
| 387 | |
| 388 | switch (event) { |
| 389 | case GSCON_EV_A_ASSIGNMENT_CMD: |
| 390 | /* MSC requests us to perform assignment, this code section is |
| 391 | * triggered via signal GSCON_EV_A_ASSIGNMENT_CMD from |
| 392 | * bssmap_handle_assignm_req() in osmo_bsc_bssap.c, which does |
| 393 | * the parsing of incoming assignment requests. */ |
| 394 | |
| 395 | LOGPFSML(fi, LOGL_NOTICE, "Channel assignment: chan_mode=%s, full_rate=%i\n", |
| 396 | get_value_string(gsm48_chan_mode_names, conn->user_plane.chan_mode), |
| 397 | conn->user_plane.full_rate); |
| 398 | |
| 399 | /* FIXME: We need to check if current channel is sufficient. If |
| 400 | * yes, do MODIFY. If not, do assignment (see commented lines below) */ |
| 401 | |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 402 | switch (conn->user_plane.chan_mode) { |
| 403 | case GSM48_CMODE_SPEECH_V1: |
| 404 | case GSM48_CMODE_SPEECH_EFR: |
| 405 | case GSM48_CMODE_SPEECH_AMR: |
| 406 | /* A voice channel is requested, so we run down the |
| 407 | * mgcp-ass-mgcp state-chain (see FIXME above) */ |
| 408 | memset(&conn_peer, 0, sizeof(conn_peer)); |
| 409 | conn_peer.call_id = conn->sccp.conn_id; |
| 410 | osmo_strlcpy(conn_peer.endpoint, ENDPOINT_ID, sizeof(conn_peer.endpoint)); |
| 411 | |
| 412 | /* (Pre)Change state and create the connection */ |
| 413 | osmo_fsm_inst_state_chg(fi, ST_WAIT_CRCX_BTS, MGCP_MGW_TIMEOUT, MGCP_MGW_TIMEOUT_TIMER_NR); |
| 414 | conn->user_plane.fi_bts = |
| 415 | mgcp_conn_create(conn->network->mgw.client, fi, GSCON_EV_MGW_FAIL_BTS, |
| 416 | GSCON_EV_MGW_CRCX_RESP_BTS, &conn_peer); |
| 417 | if (!conn->user_plane.fi_bts) { |
| 418 | resp = gsm0808_create_assignment_failure(GSM0808_CAUSE_EQUIPMENT_FAILURE, NULL); |
| 419 | sigtran_send(conn, resp, fi); |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 420 | return; |
| 421 | } |
| 422 | break; |
| 423 | case GSM48_CMODE_SIGN: |
| 424 | /* A signalling channel is requested, so we perform the |
| 425 | * channel assignment directly without performing any |
| 426 | * MGCP actions. ST_WAIT_ASS_CMPL will see by the |
| 427 | * conn->user_plane.chan_mode parameter that this |
| 428 | * assignment is for a signalling channel and will then |
| 429 | * change back to ST_ACTIVE (here) immediately. */ |
Harald Welte | 6900f81 | 2018-03-21 21:29:03 +0100 | [diff] [blame] | 430 | rc = gsm0808_assign_req(conn, conn->user_plane.chan_mode, |
| 431 | conn->user_plane.full_rate); |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 432 | if (rc != 0) { |
| 433 | resp = gsm0808_create_assignment_failure(GSM0808_CAUSE_EQUIPMENT_FAILURE, NULL); |
| 434 | sigtran_send(conn, resp, fi); |
| 435 | return; |
| 436 | } |
| 437 | |
| 438 | osmo_fsm_inst_state_chg(fi, ST_WAIT_ASS_CMPL, GSM0808_T10_VALUE, GSM0808_T10_TIMER_NR); |
| 439 | break; |
| 440 | default: |
| 441 | /* An unsupported channel is requested, so we have to |
| 442 | * reject this request by sending an assignment failure |
| 443 | * message immediately */ |
Pau Espin Pedrol | 55677de | 2018-03-17 01:12:33 +0100 | [diff] [blame] | 444 | LOGPFSML(fi, LOGL_ERROR, "Requested channel mode is not supported! chan_mode=%s full_rate=%d\n", |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 445 | get_value_string(gsm48_chan_mode_names, conn->user_plane.chan_mode), |
| 446 | conn->user_plane.full_rate); |
| 447 | |
| 448 | /* The requested channel mode is not supported */ |
| 449 | resp = gsm0808_create_assignment_failure(GSM0808_CAUSE_REQ_CODEC_TYPE_OR_CONFIG_NOT_SUPP, NULL); |
| 450 | sigtran_send(conn, resp, fi); |
| 451 | break; |
| 452 | } |
| 453 | break; |
| 454 | case GSCON_EV_HO_START: |
| 455 | rc = bsc_handover_start_gscon(conn); |
| 456 | if (rc) { |
| 457 | resp = gsm0808_create_clear_rqst(GSM0808_CAUSE_EQUIPMENT_FAILURE); |
| 458 | sigtran_send(conn, resp, fi); |
| 459 | osmo_fsm_inst_state_chg(fi, ST_CLEARING, 0, 0); |
| 460 | return; |
| 461 | } |
| 462 | |
| 463 | /* Note: No timeout is set here, T3103 in handover_logic.c |
| 464 | * will generate a GSCON_EV_HO_TIMEOUT event should the |
| 465 | * handover time out, so we do not need another timeout |
| 466 | * here (maybe its worth to think about giving GSCON |
| 467 | * more power over the actual handover process). */ |
| 468 | osmo_fsm_inst_state_chg(fi, ST_WAIT_HO_COMPL, 0, 0); |
| 469 | break; |
| 470 | case GSCON_EV_A_HO_REQ: |
| 471 | /* FIXME: reject any handover requests with HO FAIL until implemented */ |
| 472 | break; |
| 473 | case GSCON_EV_MO_DTAP: |
Philipp Maier | 4be98dc | 2018-03-21 11:07:53 +0100 | [diff] [blame] | 474 | forward_dtap(conn, (struct msgb *)data, fi); |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 475 | break; |
| 476 | case GSCON_EV_MT_DTAP: |
| 477 | submit_dtap(conn, (struct msgb *)data, fi); |
| 478 | break; |
| 479 | case GSCON_EV_TX_SCCP: |
| 480 | sigtran_send(conn, (struct msgb *)data, fi); |
| 481 | break; |
| 482 | default: |
| 483 | OSMO_ASSERT(false); |
| 484 | break; |
| 485 | } |
| 486 | } |
| 487 | |
| 488 | /* Before we may start the channel assignment we need to get an IP/Port for the |
| 489 | * RTP connection from the MGW */ |
| 490 | static void gscon_fsm_wait_crcx_bts(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 491 | { |
| 492 | struct gsm_subscriber_connection *conn = fi->priv; |
| 493 | struct mgcp_conn_peer *conn_peer = NULL; |
| 494 | struct msgb *resp = NULL; |
| 495 | int rc; |
| 496 | |
| 497 | switch (event) { |
| 498 | case GSCON_EV_MGW_CRCX_RESP_BTS: |
| 499 | conn_peer = data; |
| 500 | |
Philipp Maier | 393165c | 2018-03-21 11:15:33 +0100 | [diff] [blame] | 501 | /* Check if the MGW has assigned an enpoint to us, otherwise we |
| 502 | * can not proceed. */ |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 503 | if (strlen(conn_peer->endpoint) <= 0) { |
| 504 | resp = gsm0808_create_assignment_failure(GSM0808_CAUSE_EQUIPMENT_FAILURE, NULL); |
| 505 | sigtran_send(conn, resp, fi); |
| 506 | osmo_fsm_inst_state_chg(fi, ST_ACTIVE, 0, 0); |
| 507 | return; |
| 508 | } |
| 509 | |
| 510 | /* Memorize the endpoint name we got assigned from the MGW. |
| 511 | * When the BTS sided connection is done, we need to create |
| 512 | * a second connection on that same endpoint, so we need |
| 513 | * to know its ID */ |
| 514 | if (!conn->user_plane.mgw_endpoint) |
| 515 | conn->user_plane.mgw_endpoint = talloc_zero_size(conn, MGCP_ENDPOINT_MAXLEN); |
| 516 | OSMO_ASSERT(conn->user_plane.mgw_endpoint); |
| 517 | osmo_strlcpy(conn->user_plane.mgw_endpoint, conn_peer->endpoint, MGCP_ENDPOINT_MAXLEN); |
| 518 | |
| 519 | /* Store the IP-Address and the port the MGW assigned to us, |
| 520 | * then start the channel assignment. */ |
| 521 | conn->user_plane.rtp_port = conn_peer->port; |
| 522 | conn->user_plane.rtp_ip = osmo_ntohl(inet_addr(conn_peer->addr)); |
Harald Welte | 6900f81 | 2018-03-21 21:29:03 +0100 | [diff] [blame] | 523 | rc = gsm0808_assign_req(conn, conn->user_plane.chan_mode, conn->user_plane.full_rate); |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 524 | if (rc != 0) { |
| 525 | resp = gsm0808_create_assignment_failure(GSM0808_CAUSE_RQSTED_SPEECH_VERSION_UNAVAILABLE, NULL); |
| 526 | sigtran_send(conn, resp, fi); |
| 527 | osmo_fsm_inst_state_chg(fi, ST_ACTIVE, 0, 0); |
| 528 | return; |
| 529 | } |
| 530 | |
| 531 | osmo_fsm_inst_state_chg(fi, ST_WAIT_ASS_CMPL, GSM0808_T10_VALUE, GSM0808_T10_TIMER_NR); |
| 532 | break; |
| 533 | case GSCON_EV_MO_DTAP: |
Philipp Maier | 4be98dc | 2018-03-21 11:07:53 +0100 | [diff] [blame] | 534 | forward_dtap(conn, (struct msgb *)data, fi); |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 535 | break; |
| 536 | case GSCON_EV_MT_DTAP: |
| 537 | submit_dtap(conn, (struct msgb *)data, fi); |
| 538 | break; |
| 539 | case GSCON_EV_TX_SCCP: |
| 540 | sigtran_send(conn, (struct msgb *)data, fi); |
| 541 | break; |
| 542 | default: |
| 543 | OSMO_ASSERT(false); |
| 544 | break; |
| 545 | } |
| 546 | } |
| 547 | |
| 548 | /* We're waiting for an ASSIGNMENT COMPLETE from MS */ |
| 549 | static void gscon_fsm_wait_ass_cmpl(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 550 | { |
| 551 | struct gsm_subscriber_connection *conn = fi->priv; |
| 552 | struct gsm_lchan *lchan = conn->lchan; |
| 553 | struct mgcp_conn_peer conn_peer; |
| 554 | struct in_addr addr; |
| 555 | struct msgb *resp = NULL; |
| 556 | int rc; |
| 557 | |
| 558 | switch (event) { |
| 559 | case GSCON_EV_RR_ASS_COMPL: |
| 560 | switch (conn->user_plane.chan_mode) { |
| 561 | case GSM48_CMODE_SPEECH_V1: |
| 562 | case GSM48_CMODE_SPEECH_EFR: |
| 563 | case GSM48_CMODE_SPEECH_AMR: |
| 564 | /* FIXME: What if we are using SCCP-Lite? */ |
| 565 | |
| 566 | /* We are dealing with a voice channel, so we can not |
| 567 | * confirm the assignment directly. We must first do |
| 568 | * some final steps on the MGCP side. */ |
| 569 | |
| 570 | /* Prepare parameters with the information we got during the assignment */ |
| 571 | memset(&conn_peer, 0, sizeof(conn_peer)); |
| 572 | addr.s_addr = osmo_ntohl(lchan->abis_ip.bound_ip); |
| 573 | osmo_strlcpy(conn_peer.addr, inet_ntoa(addr), sizeof(conn_peer.addr)); |
| 574 | conn_peer.port = lchan->abis_ip.bound_port; |
| 575 | |
| 576 | /* (Pre)Change state and modify the connection */ |
| 577 | osmo_fsm_inst_state_chg(fi, ST_WAIT_MDCX_BTS, MGCP_MGW_TIMEOUT, MGCP_MGW_TIMEOUT_TIMER_NR); |
| 578 | rc = mgcp_conn_modify(conn->user_plane.fi_bts, GSCON_EV_MGW_MDCX_RESP_BTS, &conn_peer); |
| 579 | if (rc != 0) { |
| 580 | resp = gsm0808_create_assignment_failure(GSM0808_CAUSE_EQUIPMENT_FAILURE, NULL); |
| 581 | sigtran_send(conn, resp, fi); |
| 582 | osmo_fsm_inst_state_chg(fi, ST_ACTIVE, 0, 0); |
| 583 | return; |
| 584 | } |
| 585 | break; |
| 586 | case GSM48_CMODE_SIGN: |
| 587 | /* Confirm the successful assignment on BSSMAP and |
| 588 | * change back into active state */ |
| 589 | send_ass_compl(lchan, fi); |
| 590 | osmo_fsm_inst_state_chg(fi, ST_ACTIVE, 0, 0); |
| 591 | break; |
| 592 | default: |
| 593 | /* Unsupported modes should have been already filtered |
| 594 | * by gscon_fsm_active(). If we reach the default |
| 595 | * section here anyway than some unsupported mode must |
| 596 | * have made it into the FSM, this would be a bug, so |
| 597 | * we fire an assertion here */ |
| 598 | OSMO_ASSERT(false); |
| 599 | break; |
| 600 | } |
| 601 | |
| 602 | break; |
| 603 | case GSCON_EV_RR_ASS_FAIL: |
| 604 | resp = gsm0808_create_assignment_failure(GSM0808_CAUSE_RQSTED_TERRESTRIAL_RESOURCE_UNAVAILABLE, NULL); |
| 605 | sigtran_send(conn, resp, fi); |
| 606 | osmo_fsm_inst_state_chg(fi, ST_ACTIVE, 0, 0); |
| 607 | break; |
| 608 | case GSCON_EV_MO_DTAP: |
Philipp Maier | 4be98dc | 2018-03-21 11:07:53 +0100 | [diff] [blame] | 609 | forward_dtap(conn, (struct msgb *)data, fi); |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 610 | break; |
| 611 | case GSCON_EV_MT_DTAP: |
| 612 | submit_dtap(conn, (struct msgb *)data, fi); |
| 613 | break; |
| 614 | case GSCON_EV_TX_SCCP: |
| 615 | sigtran_send(conn, (struct msgb *)data, fi); |
| 616 | break; |
| 617 | default: |
| 618 | OSMO_ASSERT(false); |
| 619 | break; |
| 620 | } |
| 621 | } |
| 622 | |
| 623 | /* We are waiting for the MGW response to the MDCX */ |
| 624 | static void gscon_fsm_wait_mdcx_bts(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 625 | { |
| 626 | struct gsm_subscriber_connection *conn = fi->priv; |
| 627 | struct mgcp_conn_peer conn_peer; |
| 628 | struct sockaddr_in *sin = NULL; |
| 629 | struct msgb *resp = NULL; |
| 630 | |
| 631 | switch (event) { |
| 632 | case GSCON_EV_MGW_MDCX_RESP_BTS: |
| 633 | |
| 634 | /* Prepare parameters with the connection information we got |
| 635 | * with the assignment command */ |
| 636 | memset(&conn_peer, 0, sizeof(conn_peer)); |
| 637 | conn_peer.call_id = conn->sccp.conn_id; |
| 638 | sin = (struct sockaddr_in *)&conn->user_plane.aoip_rtp_addr_remote; |
| 639 | conn_peer.port = osmo_ntohs(sin->sin_port); |
| 640 | osmo_strlcpy(conn_peer.addr, inet_ntoa(sin->sin_addr), sizeof(conn_peer.addr)); |
| 641 | |
| 642 | /* Make sure we use the same endpoint where we created the |
| 643 | * BTS connection. */ |
| 644 | osmo_strlcpy(conn_peer.endpoint, conn->user_plane.mgw_endpoint, sizeof(conn_peer.endpoint)); |
| 645 | |
| 646 | /* (Pre)Change state and create the connection */ |
| 647 | osmo_fsm_inst_state_chg(fi, ST_WAIT_CRCX_MSC, MGCP_MGW_TIMEOUT, MGCP_MGW_TIMEOUT_TIMER_NR); |
| 648 | conn->user_plane.fi_msc = |
| 649 | mgcp_conn_create(conn->network->mgw.client, fi, GSCON_EV_MGW_FAIL_MSC, GSCON_EV_MGW_CRCX_RESP_MSC, |
| 650 | &conn_peer); |
| 651 | if (!conn->user_plane.fi_bts) { |
| 652 | resp = gsm0808_create_assignment_failure(GSM0808_CAUSE_EQUIPMENT_FAILURE, NULL); |
| 653 | sigtran_send(conn, resp, fi); |
| 654 | osmo_fsm_inst_state_chg(fi, ST_ACTIVE, 0, 0); |
| 655 | return; |
| 656 | } |
| 657 | |
| 658 | break; |
| 659 | case GSCON_EV_MO_DTAP: |
Philipp Maier | 4be98dc | 2018-03-21 11:07:53 +0100 | [diff] [blame] | 660 | forward_dtap(conn, (struct msgb *)data, fi); |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 661 | break; |
| 662 | case GSCON_EV_MT_DTAP: |
| 663 | submit_dtap(conn, (struct msgb *)data, fi); |
| 664 | break; |
| 665 | case GSCON_EV_TX_SCCP: |
| 666 | sigtran_send(conn, (struct msgb *)data, fi); |
| 667 | break; |
| 668 | default: |
| 669 | OSMO_ASSERT(false); |
| 670 | break; |
| 671 | } |
| 672 | } |
| 673 | |
| 674 | static void gscon_fsm_wait_crcx_msc(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 675 | { |
| 676 | struct gsm_subscriber_connection *conn = fi->priv; |
| 677 | struct mgcp_conn_peer *conn_peer = NULL; |
| 678 | struct gsm_lchan *lchan = conn->lchan; |
| 679 | struct sockaddr_in *sin = NULL; |
| 680 | |
| 681 | switch (event) { |
| 682 | case GSCON_EV_MGW_CRCX_RESP_MSC: |
| 683 | conn_peer = data; |
| 684 | |
| 685 | /* Store address information we got in response from the CRCX command. */ |
| 686 | sin = (struct sockaddr_in *)&conn->user_plane.aoip_rtp_addr_local; |
| 687 | sin->sin_family = AF_INET; |
| 688 | sin->sin_addr.s_addr = inet_addr(conn_peer->addr); |
| 689 | sin->sin_port = osmo_ntohs(conn_peer->port); |
| 690 | |
| 691 | /* Send assignment complete message to the MSC */ |
| 692 | send_ass_compl(lchan, fi); |
| 693 | |
| 694 | osmo_fsm_inst_state_chg(fi, ST_ACTIVE, 0, 0); |
| 695 | |
| 696 | break; |
| 697 | case GSCON_EV_MO_DTAP: |
Philipp Maier | 4be98dc | 2018-03-21 11:07:53 +0100 | [diff] [blame] | 698 | forward_dtap(conn, (struct msgb *)data, fi); |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 699 | break; |
| 700 | case GSCON_EV_MT_DTAP: |
| 701 | submit_dtap(conn, (struct msgb *)data, fi); |
| 702 | break; |
| 703 | case GSCON_EV_TX_SCCP: |
| 704 | sigtran_send(conn, (struct msgb *)data, fi); |
| 705 | break; |
| 706 | default: |
| 707 | OSMO_ASSERT(false); |
| 708 | break; |
| 709 | } |
| 710 | } |
| 711 | |
| 712 | /* We're waiting for a MODE MODIFY ACK from MS + BTS */ |
| 713 | static void gscon_fsm_wait_mode_modify_ack(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 714 | { |
| 715 | struct gsm_subscriber_connection *conn = fi->priv; |
| 716 | struct gsm_lchan *lchan = conn->lchan; |
| 717 | |
| 718 | switch (event) { |
| 719 | case GSCON_EV_RR_MODE_MODIFY_ACK: |
| 720 | /* we assume that not only have we received the RR MODE_MODIFY_ACK, but |
| 721 | * actually that also the BTS side of the channel mode has been changed accordingly */ |
| 722 | osmo_fsm_inst_state_chg(fi, ST_ACTIVE, 0, 0); |
| 723 | |
| 724 | /* FIXME: Check if this requires special handling. For now I assume that the send_ass_compl() |
| 725 | * can be used. But I am not sure. */ |
| 726 | send_ass_compl(lchan, fi); |
| 727 | |
| 728 | break; |
| 729 | /* FIXME: Do we need to handle DTAP traffic in this state? Maybe yes? Needs to be checked. */ |
| 730 | case GSCON_EV_MO_DTAP: |
Philipp Maier | 4be98dc | 2018-03-21 11:07:53 +0100 | [diff] [blame] | 731 | forward_dtap(conn, (struct msgb *)data, fi); |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 732 | break; |
| 733 | case GSCON_EV_MT_DTAP: |
| 734 | submit_dtap(conn, (struct msgb *)data, fi); |
| 735 | break; |
| 736 | case GSCON_EV_TX_SCCP: |
| 737 | sigtran_send(conn, (struct msgb *)data, fi); |
| 738 | break; |
| 739 | default: |
| 740 | OSMO_ASSERT(false); |
| 741 | break; |
| 742 | } |
| 743 | } |
| 744 | |
| 745 | static void gscon_fsm_clearing(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 746 | { |
| 747 | struct gsm_subscriber_connection *conn = fi->priv; |
| 748 | struct msgb *resp; |
| 749 | |
| 750 | switch (event) { |
| 751 | case GSCON_EV_RSL_CLEAR_COMPL: |
| 752 | resp = gsm0808_create_clear_complete(); |
| 753 | sigtran_send(conn, resp, fi); |
| 754 | osmo_fsm_inst_term(fi, OSMO_FSM_TERM_REGULAR, data); |
| 755 | break; |
| 756 | default: |
| 757 | OSMO_ASSERT(false); |
| 758 | break; |
| 759 | } |
| 760 | } |
| 761 | |
| 762 | /* Wait for the handover logic to tell us whether the handover completed, |
| 763 | * failed or has timed out */ |
| 764 | static void gscon_fsm_wait_ho_compl(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 765 | { |
| 766 | struct gsm_subscriber_connection *conn = fi->priv; |
| 767 | struct mgcp_conn_peer conn_peer; |
| 768 | struct gsm_lchan *lchan = conn->lchan; |
| 769 | struct in_addr addr; |
| 770 | struct msgb *resp; |
| 771 | int rc; |
| 772 | |
| 773 | switch (event) { |
| 774 | case GSCON_EV_HO_COMPL: |
| 775 | /* The handover logic informs us that the handover has been |
| 776 | * completet. Now we have to tell the MGW the IP/Port on the |
| 777 | * new BTS so that the uplink RTP traffic can be redirected |
| 778 | * there. */ |
| 779 | |
| 780 | /* Prepare parameters with the information we got during the |
| 781 | * handover procedure (via IPACC) */ |
| 782 | memset(&conn_peer, 0, sizeof(conn_peer)); |
| 783 | addr.s_addr = osmo_ntohl(lchan->abis_ip.bound_ip); |
| 784 | osmo_strlcpy(conn_peer.addr, inet_ntoa(addr), sizeof(conn_peer.addr)); |
| 785 | conn_peer.port = lchan->abis_ip.bound_port; |
| 786 | |
| 787 | /* (Pre)Change state and modify the connection */ |
| 788 | osmo_fsm_inst_state_chg(fi, ST_WAIT_MDCX_BTS_HO, MGCP_MGW_TIMEOUT, MGCP_MGW_HO_TIMEOUT_TIMER_NR); |
| 789 | rc = mgcp_conn_modify(conn->user_plane.fi_bts, GSCON_EV_MGW_MDCX_RESP_BTS, &conn_peer); |
| 790 | if (rc != 0) { |
| 791 | resp = gsm0808_create_clear_rqst(GSM0808_CAUSE_EQUIPMENT_FAILURE); |
| 792 | sigtran_send(conn, resp, fi); |
| 793 | osmo_fsm_inst_state_chg(fi, ST_CLEARING, 0, 0); |
| 794 | return; |
| 795 | } |
| 796 | break; |
| 797 | case GSCON_EV_HO_TIMEOUT: |
| 798 | case GSCON_EV_HO_FAIL: |
| 799 | /* The handover logic informs us that the handover failed for |
| 800 | * some reason. This means the phone stays on the TS/BTS on |
| 801 | * which it currently is. We will change back to the active |
| 802 | * state again as there are no further operations needed */ |
| 803 | osmo_fsm_inst_state_chg(fi, ST_ACTIVE, 0, 0); |
| 804 | break; |
| 805 | default: |
| 806 | OSMO_ASSERT(false); |
| 807 | break; |
| 808 | } |
| 809 | } |
| 810 | |
| 811 | /* Wait for the MGW to confirm handover related modification of the connection |
| 812 | * parameters */ |
| 813 | static void gscon_fsm_wait_mdcx_bts_ho(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 814 | { |
| 815 | struct gsm_subscriber_connection *conn = fi->priv; |
| 816 | |
| 817 | switch (event) { |
| 818 | case GSCON_EV_MGW_MDCX_RESP_BTS: |
| 819 | /* The MGW has confirmed the handover MDCX, and the handover |
| 820 | * is now also done on the RTP side. We may now change back |
| 821 | * to the active state. */ |
| 822 | osmo_fsm_inst_state_chg(fi, ST_ACTIVE, 0, 0); |
| 823 | break; |
| 824 | case GSCON_EV_MO_DTAP: |
Philipp Maier | 4be98dc | 2018-03-21 11:07:53 +0100 | [diff] [blame] | 825 | forward_dtap(conn, (struct msgb *)data, fi); |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 826 | break; |
| 827 | case GSCON_EV_MT_DTAP: |
| 828 | submit_dtap(conn, (struct msgb *)data, fi); |
| 829 | break; |
| 830 | case GSCON_EV_TX_SCCP: |
| 831 | sigtran_send(conn, (struct msgb *)data, fi); |
| 832 | break; |
| 833 | default: |
| 834 | OSMO_ASSERT(false); |
| 835 | break; |
| 836 | } |
| 837 | } |
| 838 | |
| 839 | #define EV_TRANSPARENT_SCCP S(GSCON_EV_TX_SCCP) | S(GSCON_EV_MO_DTAP) | S(GSCON_EV_MT_DTAP) |
| 840 | |
| 841 | static const struct osmo_fsm_state gscon_fsm_states[] = { |
| 842 | [ST_INIT] = { |
Harald Welte | e9903fd | 2018-03-17 17:13:10 +0100 | [diff] [blame] | 843 | .name = OSMO_STRINGIFY(INIT), |
| 844 | .in_event_mask = S(GSCON_EV_A_CONN_REQ) | S(GSCON_EV_A_CONN_IND), |
| 845 | .out_state_mask = S(ST_WAIT_CC), |
| 846 | .action = gscon_fsm_init, |
| 847 | }, |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 848 | [ST_WAIT_CC] = { |
Harald Welte | e9903fd | 2018-03-17 17:13:10 +0100 | [diff] [blame] | 849 | .name = OSMO_STRINGIFY(WAIT_CC), |
| 850 | .in_event_mask = S(GSCON_EV_A_CONN_CFM), |
| 851 | .out_state_mask = S(ST_ACTIVE), |
| 852 | .action = gscon_fsm_wait_cc, |
| 853 | }, |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 854 | [ST_ACTIVE] = { |
Harald Welte | e9903fd | 2018-03-17 17:13:10 +0100 | [diff] [blame] | 855 | .name = OSMO_STRINGIFY(ACTIVE), |
| 856 | .in_event_mask = EV_TRANSPARENT_SCCP | S(GSCON_EV_A_ASSIGNMENT_CMD) | |
| 857 | S(GSCON_EV_A_HO_REQ) | S(GSCON_EV_HO_START), |
| 858 | .out_state_mask = S(ST_CLEARING) | S(ST_WAIT_CRCX_BTS) | S(ST_WAIT_ASS_CMPL) | |
| 859 | S(ST_WAIT_MODE_MODIFY_ACK) | S(ST_WAIT_MO_HO_CMD) | S(ST_WAIT_HO_COMPL), |
| 860 | .action = gscon_fsm_active, |
| 861 | }, |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 862 | [ST_WAIT_CRCX_BTS] = { |
Harald Welte | e9903fd | 2018-03-17 17:13:10 +0100 | [diff] [blame] | 863 | .name = OSMO_STRINGIFY(WAIT_CRCX_BTS), |
| 864 | .in_event_mask = EV_TRANSPARENT_SCCP | S(GSCON_EV_MGW_CRCX_RESP_BTS), |
| 865 | .out_state_mask = S(ST_ACTIVE) | S(ST_WAIT_ASS_CMPL), |
| 866 | .action = gscon_fsm_wait_crcx_bts, |
| 867 | }, |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 868 | [ST_WAIT_ASS_CMPL] = { |
Harald Welte | e9903fd | 2018-03-17 17:13:10 +0100 | [diff] [blame] | 869 | .name = OSMO_STRINGIFY(WAIT_ASS_CMPL), |
| 870 | .in_event_mask = EV_TRANSPARENT_SCCP | S(GSCON_EV_RR_ASS_COMPL) | S(GSCON_EV_RR_ASS_FAIL), |
| 871 | .out_state_mask = S(ST_ACTIVE) | S(ST_WAIT_MDCX_BTS), |
| 872 | .action = gscon_fsm_wait_ass_cmpl, |
| 873 | }, |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 874 | [ST_WAIT_MDCX_BTS] = { |
Harald Welte | e9903fd | 2018-03-17 17:13:10 +0100 | [diff] [blame] | 875 | .name = OSMO_STRINGIFY(WAIT_MDCX_BTS), |
| 876 | .in_event_mask = EV_TRANSPARENT_SCCP | S(GSCON_EV_MGW_MDCX_RESP_BTS), |
| 877 | .out_state_mask = S(ST_ACTIVE) | S(ST_WAIT_CRCX_MSC), |
| 878 | .action = gscon_fsm_wait_mdcx_bts, |
| 879 | }, |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 880 | [ST_WAIT_CRCX_MSC] = { |
Harald Welte | e9903fd | 2018-03-17 17:13:10 +0100 | [diff] [blame] | 881 | .name = OSMO_STRINGIFY(WAIT_CRCX_MSC), |
| 882 | .in_event_mask = EV_TRANSPARENT_SCCP | S(GSCON_EV_MGW_CRCX_RESP_MSC), |
| 883 | .out_state_mask = S(ST_ACTIVE), |
| 884 | .action = gscon_fsm_wait_crcx_msc, |
| 885 | }, |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 886 | [ST_WAIT_MODE_MODIFY_ACK] = { |
Harald Welte | e9903fd | 2018-03-17 17:13:10 +0100 | [diff] [blame] | 887 | .name = OSMO_STRINGIFY(WAIT_MODE_MODIFY_ACK), |
| 888 | .in_event_mask = EV_TRANSPARENT_SCCP | S(GSCON_EV_RR_MODE_MODIFY_ACK), |
| 889 | .out_state_mask = S(ST_ACTIVE) | S(ST_CLEARING), |
| 890 | .action = gscon_fsm_wait_mode_modify_ack, |
| 891 | }, |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 892 | [ST_CLEARING] = { |
Harald Welte | e9903fd | 2018-03-17 17:13:10 +0100 | [diff] [blame] | 893 | .name = OSMO_STRINGIFY(CLEARING), |
| 894 | .in_event_mask = S(GSCON_EV_RSL_CLEAR_COMPL), |
| 895 | .action = gscon_fsm_clearing, |
| 896 | }, |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 897 | |
| 898 | /* TODO: external handover, probably it makes sense to break up the |
| 899 | * program flow in handover_logic.c a bit and handle some of the logic |
| 900 | * here? */ |
| 901 | [ST_WAIT_MT_HO_ACC] = { |
Harald Welte | e9903fd | 2018-03-17 17:13:10 +0100 | [diff] [blame] | 902 | .name = OSMO_STRINGIFY(WAIT_MT_HO_ACC), |
| 903 | }, |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 904 | [ST_WAIT_MT_HO_COMPL] = { |
Harald Welte | e9903fd | 2018-03-17 17:13:10 +0100 | [diff] [blame] | 905 | .name = OSMO_STRINGIFY(WAIT_MT_HO_COMPL), |
| 906 | }, |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 907 | [ST_WAIT_MO_HO_CMD] = { |
Harald Welte | e9903fd | 2018-03-17 17:13:10 +0100 | [diff] [blame] | 908 | .name = OSMO_STRINGIFY(WAIT_MO_HO_CMD), |
| 909 | }, |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 910 | [ST_MO_HO_PROCEEDING] = { |
Harald Welte | e9903fd | 2018-03-17 17:13:10 +0100 | [diff] [blame] | 911 | .name = OSMO_STRINGIFY(MO_HO_PROCEEDING), |
| 912 | }, |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 913 | |
| 914 | /* Internal handover */ |
| 915 | [ST_WAIT_HO_COMPL] = { |
Harald Welte | e9903fd | 2018-03-17 17:13:10 +0100 | [diff] [blame] | 916 | .name = OSMO_STRINGIFY(WAIT_HO_COMPL), |
| 917 | .in_event_mask = S(GSCON_EV_HO_COMPL) | S(GSCON_EV_HO_FAIL) | S(GSCON_EV_HO_TIMEOUT), |
Philipp Maier | ecb0308 | 2018-03-26 12:05:48 +0200 | [diff] [blame] | 918 | .out_state_mask = S(ST_ACTIVE) | S(ST_WAIT_MDCX_BTS_HO) | S(ST_CLEARING), |
Harald Welte | e9903fd | 2018-03-17 17:13:10 +0100 | [diff] [blame] | 919 | .action = gscon_fsm_wait_ho_compl, |
| 920 | }, |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 921 | [ST_WAIT_MDCX_BTS_HO] = { |
Harald Welte | e9903fd | 2018-03-17 17:13:10 +0100 | [diff] [blame] | 922 | .name = OSMO_STRINGIFY(WAIT_MDCX_BTS_HO), |
| 923 | .in_event_mask = EV_TRANSPARENT_SCCP | S(GSCON_EV_MGW_MDCX_RESP_BTS), |
| 924 | .action = gscon_fsm_wait_mdcx_bts_ho, |
| 925 | .out_state_mask = S(ST_ACTIVE), |
| 926 | }, |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 927 | }; |
| 928 | |
| 929 | static void gscon_fsm_allstate(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 930 | { |
| 931 | struct gsm_subscriber_connection *conn = fi->priv; |
| 932 | struct msgb *resp = NULL; |
| 933 | |
| 934 | /* When a connection on the MGW fails, make sure that the reference |
| 935 | * in our book-keeping is erased. */ |
| 936 | switch (event) { |
| 937 | case GSCON_EV_MGW_FAIL_BTS: |
| 938 | conn->user_plane.fi_bts = NULL; |
| 939 | break; |
| 940 | case GSCON_EV_MGW_FAIL_MSC: |
| 941 | conn->user_plane.fi_msc = NULL; |
| 942 | break; |
| 943 | } |
| 944 | |
| 945 | /* Regular allstate event processing */ |
| 946 | switch (event) { |
| 947 | case GSCON_EV_MGW_FAIL_BTS: |
| 948 | case GSCON_EV_MGW_FAIL_MSC: |
| 949 | /* Note: An MGW connection die per definition at any time. |
| 950 | * However, if it dies during the assignment we must return |
| 951 | * with an assignment failure */ |
Philipp Maier | 70fcde6 | 2018-03-21 11:17:32 +0100 | [diff] [blame] | 952 | OSMO_ASSERT(fi->state != ST_INIT && fi->state != ST_WAIT_CC); |
| 953 | if (fi->state == ST_WAIT_CRCX_BTS || fi->state == ST_WAIT_ASS_CMPL || fi->state == ST_WAIT_MDCX_BTS |
| 954 | || fi->state == ST_WAIT_CRCX_MSC) { |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 955 | resp = gsm0808_create_assignment_failure(GSM0808_CAUSE_EQUIPMENT_FAILURE, NULL); |
| 956 | sigtran_send(conn, resp, fi); |
| 957 | osmo_fsm_inst_state_chg(fi, ST_ACTIVE, 0, 0); |
| 958 | } |
| 959 | break; |
| 960 | case GSCON_EV_A_CLEAR_CMD: |
| 961 | /* MSC tells us to cleanly shut down */ |
| 962 | osmo_fsm_inst_state_chg(fi, ST_CLEARING, 0, 0); |
| 963 | gsm0808_clear(conn); |
| 964 | /* FIXME: Release all terestrial resources in ST_CLEARING */ |
| 965 | /* According to 3GPP 48.008 3.1.9.1. "The BSS need not wait for the radio channel |
| 966 | * release to be completed or for the guard timer to expire before returning the |
| 967 | * CLEAR COMPLETE message" */ |
| 968 | |
| 969 | /* Close MGCP connections */ |
| 970 | toss_mgcp_conn(conn, fi); |
| 971 | |
| 972 | /* FIXME: Question: Is this a hack to force a clear complete from internel? |
| 973 | * nobody seems to send the event from outside? */ |
| 974 | osmo_fsm_inst_dispatch(conn->fi, GSCON_EV_RSL_CLEAR_COMPL, NULL); |
| 975 | break; |
| 976 | case GSCON_EV_A_DISC_IND: |
| 977 | /* MSC or SIGTRAN network has hard-released SCCP connection, |
| 978 | * terminate the FSM now. */ |
| 979 | osmo_fsm_inst_term(fi, OSMO_FSM_TERM_REGULAR, data); |
| 980 | break; |
| 981 | case GSCON_EV_RLL_REL_IND: |
| 982 | /* BTS reports that one of the LAPDm data links was released */ |
| 983 | /* send proper clear request to MSC */ |
| 984 | LOGPFSML(fi, LOGL_DEBUG, "Tx BSSMAP CLEAR REQUEST to MSC\n"); |
| 985 | resp = gsm0808_create_clear_rqst(GSM0808_CAUSE_RADIO_INTERFACE_MESSAGE_FAILURE); |
| 986 | sigtran_send(conn, resp, fi); |
| 987 | break; |
| 988 | case GSCON_EV_RSL_CONN_FAIL: |
| 989 | LOGPFSML(fi, LOGL_DEBUG, "Tx BSSMAP CLEAR REQUEST to MSC\n"); |
| 990 | resp = gsm0808_create_clear_rqst(GSM0808_CAUSE_RADIO_INTERFACE_FAILURE); |
| 991 | sigtran_send(conn, resp, fi); |
| 992 | break; |
| 993 | default: |
| 994 | OSMO_ASSERT(false); |
| 995 | break; |
| 996 | } |
| 997 | } |
| 998 | |
| 999 | void ho_dtap_cache_flush(struct gsm_subscriber_connection *conn, int send); |
| 1000 | |
| 1001 | static void gscon_cleanup(struct osmo_fsm_inst *fi, enum osmo_fsm_term_cause cause) |
| 1002 | { |
| 1003 | struct gsm_subscriber_connection *conn = fi->priv; |
| 1004 | |
| 1005 | if (conn->ho) { |
| 1006 | LOGPFSML(fi, LOGL_DEBUG, "Releasing handover state\n"); |
| 1007 | bsc_clear_handover(conn, 1); |
| 1008 | conn->ho = NULL; |
| 1009 | } |
| 1010 | |
| 1011 | if (conn->secondary_lchan) { |
| 1012 | LOGPFSML(fi, LOGL_DEBUG, "Releasing secondary_lchan\n"); |
| 1013 | lchan_release(conn->secondary_lchan, 0, RSL_REL_LOCAL_END); |
| 1014 | conn->secondary_lchan = NULL; |
| 1015 | } |
| 1016 | if (conn->lchan) { |
| 1017 | LOGPFSML(fi, LOGL_DEBUG, "Releasing lchan\n"); |
| 1018 | lchan_release(conn->lchan, 0, RSL_REL_LOCAL_END); |
| 1019 | conn->lchan = NULL; |
| 1020 | } |
| 1021 | |
| 1022 | if (conn->bsub) { |
| 1023 | LOGPFSML(fi, LOGL_DEBUG, "Putting bsc_subscr\n"); |
| 1024 | bsc_subscr_put(conn->bsub); |
| 1025 | conn->bsub = NULL; |
| 1026 | } |
| 1027 | |
| 1028 | if (conn->sccp.state != SUBSCR_SCCP_ST_NONE) { |
| 1029 | LOGPFSML(fi, LOGL_DEBUG, "Disconnecting SCCP\n"); |
| 1030 | struct bsc_msc_data *msc = conn->sccp.msc; |
| 1031 | /* FIXME: include a proper cause value / error message? */ |
| 1032 | osmo_sccp_tx_disconn(msc->a.sccp_user, conn->sccp.conn_id, &msc->a.bsc_addr, 0); |
| 1033 | conn->sccp.state = SUBSCR_SCCP_ST_NONE; |
| 1034 | } |
| 1035 | |
| 1036 | /* drop pending messages */ |
| 1037 | ho_dtap_cache_flush(conn, 0); |
| 1038 | |
| 1039 | penalty_timers_free(&conn->hodec2.penalty_timers); |
| 1040 | |
| 1041 | llist_del(&conn->entry); |
| 1042 | talloc_free(conn); |
| 1043 | fi->priv = NULL; |
| 1044 | } |
| 1045 | |
| 1046 | static void gscon_pre_term(struct osmo_fsm_inst *fi, enum osmo_fsm_term_cause cause) |
| 1047 | { |
| 1048 | struct gsm_subscriber_connection *conn = fi->priv; |
| 1049 | |
| 1050 | /* Make sure all possibly still open MGCP connections get closed */ |
| 1051 | toss_mgcp_conn(conn, fi); |
| 1052 | } |
| 1053 | |
| 1054 | static int gscon_timer_cb(struct osmo_fsm_inst *fi) |
| 1055 | { |
| 1056 | struct gsm_subscriber_connection *conn = fi->priv; |
| 1057 | struct msgb *resp = NULL; |
| 1058 | |
| 1059 | switch (fi->T) { |
| 1060 | case 993210: |
Philipp Maier | 3ddb12d | 2018-04-13 16:47:26 +0200 | [diff] [blame^] | 1061 | /* MSC has not responded/confirmed connection with CC, this |
| 1062 | * could indicate a bad SCCP connection. We now inform the the |
| 1063 | * FSM that controls the BSSMAP reset about the event. Maybe |
| 1064 | * a BSSMAP reset is necessary. */ |
| 1065 | a_reset_conn_fail(conn->sccp.msc->a.reset); |
| 1066 | |
| 1067 | /* Since we could not reach the MSC, we give up and terminate |
| 1068 | * the FSM instance now (N-DISCONNET.req is sent in |
| 1069 | * gscon_cleanup() above) */ |
Harald Welte | 3561bd4 | 2018-01-28 03:04:16 +0100 | [diff] [blame] | 1070 | osmo_fsm_inst_term(fi, OSMO_FSM_TERM_REGULAR, NULL); |
| 1071 | break; |
| 1072 | case GSM0808_T10_TIMER_NR: /* Assignment Failed */ |
| 1073 | resp = gsm0808_create_assignment_failure(GSM0808_CAUSE_RADIO_INTERFACE_FAILURE, NULL); |
| 1074 | sigtran_send(conn, resp, fi); |
| 1075 | osmo_fsm_inst_state_chg(fi, ST_ACTIVE, 0, 0); |
| 1076 | break; |
| 1077 | case MGCP_MGW_TIMEOUT_TIMER_NR: /* Assignment failed (no response from MGW) */ |
| 1078 | resp = gsm0808_create_assignment_failure(GSM0808_CAUSE_EQUIPMENT_FAILURE, NULL); |
| 1079 | sigtran_send(conn, resp, fi); |
| 1080 | osmo_fsm_inst_state_chg(fi, ST_ACTIVE, 0, 0); |
| 1081 | break; |
| 1082 | case MGCP_MGW_HO_TIMEOUT_TIMER_NR: /* Handover failed (no response from MGW) */ |
| 1083 | osmo_fsm_inst_state_chg(fi, ST_ACTIVE, 0, 0); |
| 1084 | break; |
| 1085 | default: |
| 1086 | OSMO_ASSERT(false); |
| 1087 | } |
| 1088 | return 0; |
| 1089 | } |
| 1090 | |
| 1091 | static struct osmo_fsm gscon_fsm = { |
| 1092 | .name = "SUBSCR_CONN", |
| 1093 | .states = gscon_fsm_states, |
| 1094 | .num_states = ARRAY_SIZE(gscon_fsm_states), |
| 1095 | .allstate_event_mask = S(GSCON_EV_A_DISC_IND) | S(GSCON_EV_A_CLEAR_CMD) | S(GSCON_EV_RSL_CONN_FAIL) | |
| 1096 | S(GSCON_EV_RLL_REL_IND) | S(GSCON_EV_MGW_FAIL_BTS) | S(GSCON_EV_MGW_FAIL_MSC), |
| 1097 | .allstate_action = gscon_fsm_allstate, |
| 1098 | .cleanup = gscon_cleanup, |
| 1099 | .pre_term = gscon_pre_term, |
| 1100 | .timer_cb = gscon_timer_cb, |
| 1101 | .log_subsys = DMSC, |
| 1102 | .event_names = gscon_fsm_event_names, |
| 1103 | }; |
| 1104 | |
| 1105 | /* Allocate a subscriber connection and its associated FSM */ |
| 1106 | struct gsm_subscriber_connection *bsc_subscr_con_allocate(struct gsm_network *net) |
| 1107 | { |
| 1108 | struct gsm_subscriber_connection *conn; |
| 1109 | static bool g_initialized = false; |
| 1110 | |
| 1111 | if (!g_initialized) { |
| 1112 | osmo_fsm_register(&gscon_fsm); |
| 1113 | g_initialized = true; |
| 1114 | } |
| 1115 | |
| 1116 | conn = talloc_zero(net, struct gsm_subscriber_connection); |
| 1117 | if (!conn) |
| 1118 | return NULL; |
| 1119 | |
| 1120 | conn->network = net; |
| 1121 | INIT_LLIST_HEAD(&conn->ho_dtap_cache); |
| 1122 | /* BTW, penalty timers will be initialized on-demand. */ |
| 1123 | conn->sccp.conn_id = -1; |
| 1124 | |
| 1125 | /* don't allocate from 'conn' context, as gscon_cleanup() will call talloc_free(conn) before |
| 1126 | * libosmocore will call talloc_free(conn->fi), i.e. avoid use-after-free during cleanup */ |
| 1127 | conn->fi = osmo_fsm_inst_alloc(&gscon_fsm, net, conn, LOGL_NOTICE, NULL); |
| 1128 | if (!conn->fi) { |
| 1129 | talloc_free(conn); |
| 1130 | return NULL; |
| 1131 | } |
| 1132 | |
| 1133 | llist_add_tail(&conn->entry, &net->subscr_conns); |
| 1134 | return conn; |
| 1135 | } |