Harald Welte | b8b85a1 | 2016-06-17 00:06:42 +0200 | [diff] [blame^] | 1 | /* MSC subscriber connection implementation */ |
| 2 | |
| 3 | /* |
| 4 | * (C) 2016 by sysmocom s.m.f.c. <info@sysmocom.de> |
| 5 | * All Rights Reserved |
| 6 | * |
| 7 | * Author: Neels Hofmeyr |
| 8 | * |
| 9 | * This program is free software; you can redistribute it and/or modify |
| 10 | * it under the terms of the GNU Affero General Public License as published by |
| 11 | * the Free Software Foundation; either version 3 of the License, or |
| 12 | * (at your option) any later version. |
| 13 | * |
| 14 | * This program is distributed in the hope that it will be useful, |
| 15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 17 | * GNU Affero General Public License for more details. |
| 18 | * |
| 19 | * You should have received a copy of the GNU Affero General Public License |
| 20 | * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 21 | * |
| 22 | */ |
| 23 | |
| 24 | #include <osmocom/core/logging.h> |
| 25 | #include <osmocom/core/fsm.h> |
| 26 | |
| 27 | #include <openbsc/osmo_msc.h> |
| 28 | #include <openbsc/vlr.h> |
| 29 | #include <openbsc/debug.h> |
| 30 | #include <openbsc/transaction.h> |
| 31 | |
| 32 | static const struct value_string subscr_conn_fsm_event_names[] = { |
| 33 | OSMO_VALUE_STRING(SUBSCR_CONN_E_INVALID), |
| 34 | OSMO_VALUE_STRING(SUBSCR_CONN_E_ACCEPTED), |
| 35 | OSMO_VALUE_STRING(SUBSCR_CONN_E_BUMP), |
| 36 | OSMO_VALUE_STRING(SUBSCR_CONN_E_MO_CLOSE), |
| 37 | OSMO_VALUE_STRING(SUBSCR_CONN_E_CN_CLOSE), |
| 38 | OSMO_VALUE_STRING(SUBSCR_CONN_E_CLOSE_CONF), |
| 39 | { 0, NULL } |
| 40 | }; |
| 41 | |
| 42 | const struct value_string subscr_conn_from_names[] = { |
| 43 | OSMO_VALUE_STRING(SUBSCR_CONN_FROM_INVALID), |
| 44 | OSMO_VALUE_STRING(SUBSCR_CONN_FROM_LU), |
| 45 | OSMO_VALUE_STRING(SUBSCR_CONN_FROM_CM_SERVICE_REQ), |
| 46 | OSMO_VALUE_STRING(SUBSCR_CONN_FROM_PAGING_RESP), |
| 47 | { 0, NULL } |
| 48 | }; |
| 49 | |
| 50 | static void paging_resp(struct gsm_subscriber_connection *conn, |
| 51 | enum gsm_paging_event pe) |
| 52 | { |
| 53 | subscr_paging_dispatch(GSM_HOOK_RR_PAGING, pe, NULL, conn, conn->subscr); |
| 54 | } |
| 55 | |
| 56 | void subscr_conn_fsm_new(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 57 | { |
| 58 | struct gsm_subscriber_connection *conn = fi->priv; |
| 59 | enum subscr_conn_from from = SUBSCR_CONN_FROM_INVALID; |
| 60 | enum gsm_paging_event pe; |
| 61 | |
| 62 | if (data) { |
| 63 | from = *(enum subscr_conn_from*)data; |
| 64 | LOGPFSM(fi, "%s\n", subscr_conn_from_name(from)); |
| 65 | } |
| 66 | |
| 67 | /* If accepted, transition the state, all other cases mean failure. */ |
| 68 | switch (event) { |
| 69 | case SUBSCR_CONN_E_ACCEPTED: |
| 70 | osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_S_ACCEPTED, 0, 0); |
| 71 | break; |
| 72 | |
| 73 | case SUBSCR_CONN_E_MO_CLOSE: |
| 74 | case SUBSCR_CONN_E_CN_CLOSE: |
| 75 | case SUBSCR_CONN_E_CLOSE_CONF: |
| 76 | break; |
| 77 | |
| 78 | default: |
| 79 | LOGPFSM(fi, "Unexpected event: %d %s\n", |
| 80 | event, osmo_fsm_event_name(fi->fsm, event)); |
| 81 | break; |
| 82 | } |
| 83 | |
| 84 | /* if appropriate, signal paging success or failure */ |
| 85 | if (from == SUBSCR_CONN_FROM_PAGING_RESP) { |
| 86 | pe = (fi->state == SUBSCR_CONN_S_ACCEPTED)? |
| 87 | GSM_PAGING_SUCCEEDED : GSM_PAGING_EXPIRED; |
| 88 | paging_resp(conn, pe); |
| 89 | } |
| 90 | |
| 91 | /* On failure, discard the conn */ |
| 92 | if (fi->state != SUBSCR_CONN_S_ACCEPTED) { |
| 93 | /* TODO: on MO_CLOSE or CN_CLOSE, first go to RELEASING and |
| 94 | * await BSC confirmation? */ |
| 95 | osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_S_RELEASED, 0, 0); |
| 96 | return; |
| 97 | } |
| 98 | |
| 99 | /* On success, handle pending requests and/or close conn */ |
| 100 | |
| 101 | if (from == SUBSCR_CONN_FROM_CM_SERVICE_REQ) { |
| 102 | conn->received_cm_service_request = true; |
| 103 | LOGPFSM(fi, "received_cm_service_request = true\n"); |
| 104 | } |
| 105 | |
| 106 | osmo_fsm_inst_dispatch(fi, SUBSCR_CONN_E_BUMP, data); |
| 107 | } |
| 108 | |
| 109 | #if 0 |
| 110 | case SUBSCR_CONN_E_PARQ_SUCCESS: |
| 111 | osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_S_ACCEPTED, 0, 0); |
| 112 | accept_conn = true; |
| 113 | /* fall through */ |
| 114 | case SUBSCR_CONN_E_PARQ_FAILURE: |
| 115 | parq_type = data ? *(enum vlr_parq_type*)data : VLR_PR_ARQ_T_INVALID; |
| 116 | switch (parq_type) { |
| 117 | |
| 118 | case VLR_PR_ARQ_T_CM_SERV_REQ: |
| 119 | accept_conn = handle_cm_serv_result(fi, accept_conn); |
| 120 | break; |
| 121 | |
| 122 | case VLR_PR_ARQ_T_PAGING_RESP: |
| 123 | accept_conn = handle_paging_result(fi, accept_conn); |
| 124 | break; |
| 125 | |
| 126 | default: |
| 127 | LOGPFSML(fi, LOGL_ERROR, |
| 128 | "Invalid VLR Process Access Request type" |
| 129 | " %d\n", parq_type); |
| 130 | accept_conn = false; |
| 131 | break; |
| 132 | } |
| 133 | break; |
| 134 | #endif |
| 135 | |
| 136 | static void subscr_conn_fsm_bump(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 137 | { |
| 138 | struct gsm_subscriber_connection *conn = fi->priv; |
| 139 | |
| 140 | if (conn->silent_call) |
| 141 | return; |
| 142 | |
| 143 | if (conn->received_cm_service_request) |
| 144 | return; |
| 145 | |
| 146 | /* is this needed? */ |
| 147 | if (conn->subscr && !llist_empty(&conn->subscr->requests)) |
| 148 | return; |
| 149 | |
| 150 | if (trans_has_conn(conn)) |
| 151 | return; |
| 152 | |
| 153 | osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_S_RELEASED, 0, 0); |
| 154 | } |
| 155 | |
| 156 | static void subscr_conn_fsm_accepted(struct osmo_fsm_inst *fi, uint32_t event, void *data) |
| 157 | { |
| 158 | switch (event) { |
| 159 | case SUBSCR_CONN_E_BUMP: |
| 160 | subscr_conn_fsm_bump(fi, event, data); |
| 161 | return; |
| 162 | |
| 163 | default: |
| 164 | break; |
| 165 | } |
| 166 | /* Whatever unexpected happens in the accepted state, it means release. |
| 167 | * Even if an unexpected event is passed, the safest thing to do is |
| 168 | * discard the conn. We don't expect another SUBSCR_CONN_E_ACCEPTED. */ |
| 169 | osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_S_RELEASED, 0, 0); |
| 170 | } |
| 171 | |
| 172 | static void subscr_conn_fsm_release(struct osmo_fsm_inst *fi, uint32_t prev_state) |
| 173 | { |
| 174 | struct gsm_subscriber_connection *conn = fi->priv; |
| 175 | if (!conn) |
| 176 | return; |
| 177 | |
| 178 | /* temporary hack, see owned_by_msc */ |
| 179 | if (!conn->owned_by_msc) { |
| 180 | DEBUGP(DMM, "%s leaving bsc_subscr_con_free() to bsc_api.c, owned_by_msc = false\n", |
| 181 | subscr_name(conn->subscr)); |
| 182 | return; |
| 183 | } |
| 184 | |
| 185 | DEBUGP(DMM, "%s calling bsc_subscr_con_free(), owned_by_msc = true\n", |
| 186 | subscr_name(conn->subscr)); |
| 187 | gsm0808_clear(conn); |
| 188 | bsc_subscr_con_free(conn); |
| 189 | } |
| 190 | |
| 191 | #define S(x) (1 << (x)) |
| 192 | |
| 193 | static const struct osmo_fsm_state subscr_conn_fsm_states[] = { |
| 194 | [SUBSCR_CONN_S_NEW] = { |
| 195 | .name = OSMO_STRINGIFY(SUBSCR_CONN_S_NEW), |
| 196 | .in_event_mask = S(SUBSCR_CONN_E_ACCEPTED) | |
| 197 | S(SUBSCR_CONN_E_MO_CLOSE) | |
| 198 | S(SUBSCR_CONN_E_CN_CLOSE) | |
| 199 | S(SUBSCR_CONN_E_CLOSE_CONF), |
| 200 | .out_state_mask = S(SUBSCR_CONN_S_ACCEPTED) | |
| 201 | S(SUBSCR_CONN_S_RELEASED), |
| 202 | .action = subscr_conn_fsm_new, |
| 203 | }, |
| 204 | [SUBSCR_CONN_S_ACCEPTED] = { |
| 205 | .name = OSMO_STRINGIFY(SUBSCR_CONN_S_ACCEPTED), |
| 206 | /* allow everything to release for any odd behavior */ |
| 207 | .in_event_mask = S(SUBSCR_CONN_E_ACCEPTED) | |
| 208 | S(SUBSCR_CONN_E_BUMP) | |
| 209 | S(SUBSCR_CONN_E_MO_CLOSE) | |
| 210 | S(SUBSCR_CONN_E_CN_CLOSE) | |
| 211 | S(SUBSCR_CONN_E_CLOSE_CONF), |
| 212 | .out_state_mask = S(SUBSCR_CONN_S_RELEASED), |
| 213 | .action = subscr_conn_fsm_accepted, |
| 214 | }, |
| 215 | [SUBSCR_CONN_S_RELEASED] = { |
| 216 | .name = OSMO_STRINGIFY(SUBSCR_CONN_S_RELEASED), |
| 217 | .onenter = subscr_conn_fsm_release, |
| 218 | }, |
| 219 | }; |
| 220 | |
| 221 | static struct osmo_fsm subscr_conn_fsm = { |
| 222 | .name = "Subscr_Conn", |
| 223 | .states = subscr_conn_fsm_states, |
| 224 | .num_states = ARRAY_SIZE(subscr_conn_fsm_states), |
| 225 | .allstate_event_mask = 0, |
| 226 | .allstate_action = NULL, |
| 227 | .log_subsys = DVLR, |
| 228 | .event_names = subscr_conn_fsm_event_names, |
| 229 | }; |
| 230 | |
| 231 | int msc_create_conn_fsm(struct gsm_subscriber_connection *conn, const char *id) |
| 232 | { |
| 233 | struct osmo_fsm_inst *fi; |
| 234 | OSMO_ASSERT(conn); |
| 235 | |
| 236 | if (conn->conn_fsm) { |
| 237 | LOGP(DMM, LOGL_ERROR, |
| 238 | "%s: Error: connection already in use\n", id); |
| 239 | return -EINVAL; |
| 240 | } |
| 241 | |
| 242 | fi = osmo_fsm_inst_alloc(&subscr_conn_fsm, conn, conn, LOGL_DEBUG, id); |
| 243 | |
| 244 | if (!fi) { |
| 245 | LOGP(DMM, LOGL_ERROR, |
| 246 | "%s: Failed to allocate subscr conn master FSM\n", id); |
| 247 | return -ENOMEM; |
| 248 | } |
| 249 | conn->conn_fsm = fi; |
| 250 | return 0; |
| 251 | } |
| 252 | |
| 253 | bool msc_subscr_conn_is_accepted(struct gsm_subscriber_connection *conn) |
| 254 | { |
| 255 | if (!conn) |
| 256 | return false; |
| 257 | if (!conn->subscr) |
| 258 | return false; |
| 259 | if (!conn->conn_fsm) |
| 260 | return false; |
| 261 | if (conn->conn_fsm->state != SUBSCR_CONN_S_ACCEPTED) |
| 262 | return false; |
| 263 | return true; |
| 264 | } |
| 265 | |
| 266 | void msc_subscr_conn_init(void) |
| 267 | { |
| 268 | osmo_fsm_register(&subscr_conn_fsm); |
| 269 | } |