Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 1 | /* GSM silent call feature */ |
| 2 | |
| 3 | /* |
| 4 | * (C) 2009 by Harald Welte <laforge@gnumonks.org> |
| 5 | * |
| 6 | * All Rights Reserved |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify |
Harald Welte | 9af6ddf | 2011-01-01 15:25:50 +0100 | [diff] [blame] | 9 | * it under the terms of the GNU Affero General Public License as published by |
| 10 | * the Free Software Foundation; either version 3 of the License, or |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 11 | * (at your option) any later version. |
| 12 | * |
| 13 | * This program is distributed in the hope that it will be useful, |
| 14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
Harald Welte | 9af6ddf | 2011-01-01 15:25:50 +0100 | [diff] [blame] | 16 | * GNU Affero General Public License for more details. |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 17 | * |
Harald Welte | 9af6ddf | 2011-01-01 15:25:50 +0100 | [diff] [blame] | 18 | * You should have received a copy of the GNU Affero General Public License |
| 19 | * along with this program. If not, see <http://www.gnu.org/licenses/>. |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 20 | * |
| 21 | */ |
| 22 | |
| 23 | #include <stdlib.h> |
| 24 | #include <unistd.h> |
| 25 | #include <errno.h> |
| 26 | |
Pablo Neira Ayuso | 136f453 | 2011-03-22 16:47:59 +0100 | [diff] [blame] | 27 | #include <osmocom/core/msgb.h> |
Neels Hofmeyr | 9084396 | 2017-09-04 15:04:35 +0200 | [diff] [blame] | 28 | #include <osmocom/msc/signal.h> |
| 29 | #include <osmocom/msc/debug.h> |
| 30 | #include <osmocom/msc/paging.h> |
| 31 | #include <osmocom/msc/gsm_data.h> |
| 32 | #include <osmocom/msc/gsm_subscriber.h> |
| 33 | #include <osmocom/msc/abis_rsl.h> |
| 34 | #include <osmocom/msc/chan_alloc.h> |
| 35 | #include <osmocom/msc/osmo_msc.h> |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 36 | |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 37 | /* paging of the requested subscriber has completed */ |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 38 | static int paging_cb_silent(unsigned int hooknum, unsigned int event, |
Holger Hans Peter Freyther | 86481c2 | 2010-06-17 15:05:57 +0800 | [diff] [blame] | 39 | struct msgb *msg, void *_conn, void *_data) |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 40 | { |
Holger Hans Peter Freyther | 86481c2 | 2010-06-17 15:05:57 +0800 | [diff] [blame] | 41 | struct gsm_subscriber_connection *conn = _conn; |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 42 | struct scall_signal_data sigdata; |
Holger Hans Peter Freyther | a97152b | 2010-07-23 19:34:34 +0800 | [diff] [blame] | 43 | int rc = 0; |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 44 | |
| 45 | if (hooknum != GSM_HOOK_RR_PAGING) |
| 46 | return -EINVAL; |
| 47 | |
Holger Hans Peter Freyther | eff40949 | 2012-11-10 19:46:58 +0100 | [diff] [blame] | 48 | DEBUGP(DLSMS, "paging_cb_silent: "); |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 49 | |
Holger Hans Peter Freyther | 86481c2 | 2010-06-17 15:05:57 +0800 | [diff] [blame] | 50 | sigdata.conn = conn; |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 51 | sigdata.data = _data; |
| 52 | |
| 53 | switch (event) { |
| 54 | case GSM_PAGING_SUCCEEDED: |
Neels Hofmeyr | e2f24d5 | 2017-05-08 15:12:20 +0200 | [diff] [blame] | 55 | #if BEFORE_MSCSPLIT |
| 56 | /* Re-enable this log output once we can obtain this information via |
| 57 | * A-interface, see OS#2391. */ |
Holger Hans Peter Freyther | eff40949 | 2012-11-10 19:46:58 +0100 | [diff] [blame] | 58 | DEBUGPC(DLSMS, "success, using Timeslot %u on ARFCN %u\n", |
Holger Hans Peter Freyther | 86481c2 | 2010-06-17 15:05:57 +0800 | [diff] [blame] | 59 | conn->lchan->ts->nr, conn->lchan->ts->trx->arfcn); |
Neels Hofmeyr | e2f24d5 | 2017-05-08 15:12:20 +0200 | [diff] [blame] | 60 | #endif |
Holger Hans Peter Freyther | 68884aa | 2010-03-23 06:41:45 +0100 | [diff] [blame] | 61 | conn->silent_call = 1; |
Neels Hofmeyr | 6166f29 | 2017-11-22 14:33:12 +0100 | [diff] [blame] | 62 | msc_subscr_conn_get(conn, MSC_CONN_USE_SILENT_CALL); |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 63 | /* increment lchan reference count */ |
Pablo Neira Ayuso | bbc5b99 | 2011-05-06 12:12:31 +0200 | [diff] [blame] | 64 | osmo_signal_dispatch(SS_SCALL, S_SCALL_SUCCESS, &sigdata); |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 65 | break; |
| 66 | case GSM_PAGING_EXPIRED: |
Holger Hans Peter Freyther | d3baf41 | 2010-12-23 18:19:17 +0100 | [diff] [blame] | 67 | case GSM_PAGING_BUSY: |
Holger Hans Peter Freyther | 90c0aff | 2010-12-29 15:28:40 +0100 | [diff] [blame] | 68 | case GSM_PAGING_OOM: |
Holger Hans Peter Freyther | eff40949 | 2012-11-10 19:46:58 +0100 | [diff] [blame] | 69 | DEBUGP(DLSMS, "expired\n"); |
Pablo Neira Ayuso | bbc5b99 | 2011-05-06 12:12:31 +0200 | [diff] [blame] | 70 | osmo_signal_dispatch(SS_SCALL, S_SCALL_EXPIRED, &sigdata); |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 71 | break; |
| 72 | default: |
| 73 | rc = -EINVAL; |
| 74 | break; |
| 75 | } |
| 76 | |
| 77 | return rc; |
| 78 | } |
| 79 | |
Philipp Maier | e0d5caa | 2017-02-27 16:56:59 +0100 | [diff] [blame] | 80 | #if 0 |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 81 | /* receive a layer 3 message from a silent call */ |
Holger Hans Peter Freyther | 758f4df | 2010-06-21 10:34:03 +0800 | [diff] [blame] | 82 | int silent_call_rx(struct gsm_subscriber_connection *conn, struct msgb *msg) |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 83 | { |
| 84 | /* FIXME: do something like sending it through a UDP port */ |
Jacob Erlbeck | 8e68b56 | 2014-01-30 21:01:12 +0100 | [diff] [blame] | 85 | LOGP(DLSMS, LOGL_NOTICE, "Discarding L3 message from a silent call.\n"); |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 86 | return 0; |
| 87 | } |
| 88 | |
| 89 | struct msg_match { |
Holger Hans Peter Freyther | c42ad8b | 2011-04-18 17:04:00 +0200 | [diff] [blame] | 90 | uint8_t pdisc; |
| 91 | uint8_t msg_type; |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 92 | }; |
| 93 | |
| 94 | /* list of messages that are handled inside OpenBSC, even in a silent call */ |
| 95 | static const struct msg_match silent_call_accept[] = { |
| 96 | { GSM48_PDISC_MM, GSM48_MT_MM_LOC_UPD_REQUEST }, |
| 97 | { GSM48_PDISC_MM, GSM48_MT_MM_CM_SERV_REQ }, |
| 98 | }; |
| 99 | |
| 100 | /* decide if we need to reroute a message as part of a silent call */ |
Holger Hans Peter Freyther | 758f4df | 2010-06-21 10:34:03 +0800 | [diff] [blame] | 101 | int silent_call_reroute(struct gsm_subscriber_connection *conn, struct msgb *msg) |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 102 | { |
| 103 | struct gsm48_hdr *gh = msgb_l3(msg); |
Neels Hofmeyr | 531734a | 2016-03-14 16:13:24 +0100 | [diff] [blame] | 104 | uint8_t pdisc = gsm48_hdr_pdisc(gh); |
| 105 | uint8_t msg_type = gsm48_hdr_msg_type(gh); |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 106 | int i; |
| 107 | |
| 108 | /* if we're not part of a silent call, never reroute */ |
Holger Hans Peter Freyther | 758f4df | 2010-06-21 10:34:03 +0800 | [diff] [blame] | 109 | if (!conn->silent_call) |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 110 | return 0; |
| 111 | |
| 112 | /* check if we are a special message that is handled in openbsc */ |
| 113 | for (i = 0; i < ARRAY_SIZE(silent_call_accept); i++) { |
| 114 | if (silent_call_accept[i].pdisc == pdisc && |
Neels Hofmeyr | 531734a | 2016-03-14 16:13:24 +0100 | [diff] [blame] | 115 | silent_call_accept[i].msg_type == msg_type) |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 116 | return 0; |
| 117 | } |
| 118 | |
| 119 | /* otherwise, reroute */ |
Jacob Erlbeck | 8e68b56 | 2014-01-30 21:01:12 +0100 | [diff] [blame] | 120 | LOGP(DLSMS, LOGL_INFO, "Rerouting L3 message from a silent call.\n"); |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 121 | return 1; |
| 122 | } |
Philipp Maier | e0d5caa | 2017-02-27 16:56:59 +0100 | [diff] [blame] | 123 | #endif |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 124 | |
| 125 | |
| 126 | /* initiate a silent call with a given subscriber */ |
Harald Welte | 2483f1b | 2016-06-19 18:06:02 +0200 | [diff] [blame] | 127 | int gsm_silent_call_start(struct vlr_subscr *vsub, void *data, int type) |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 128 | { |
Holger Hans Peter Freyther | b618c7e | 2015-08-03 11:21:29 +0200 | [diff] [blame] | 129 | struct subscr_request *req; |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 130 | |
Neels Hofmeyr | e2f24d5 | 2017-05-08 15:12:20 +0200 | [diff] [blame] | 131 | /* FIXME the VTY command allows selecting a silent call channel type. |
| 132 | * This doesn't apply to the situation after MSCSPLIT with an |
| 133 | * A-interface. */ |
Neels Hofmeyr | 84da6b1 | 2016-05-20 21:59:55 +0200 | [diff] [blame] | 134 | req = subscr_request_conn(vsub, paging_cb_silent, data, |
| 135 | "establish silent call"); |
Holger Hans Peter Freyther | b618c7e | 2015-08-03 11:21:29 +0200 | [diff] [blame] | 136 | return req != NULL; |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 137 | } |
| 138 | |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 139 | /* end a silent call with a given subscriber */ |
Harald Welte | 2483f1b | 2016-06-19 18:06:02 +0200 | [diff] [blame] | 140 | int gsm_silent_call_stop(struct vlr_subscr *vsub) |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 141 | { |
Holger Hans Peter Freyther | 68884aa | 2010-03-23 06:41:45 +0100 | [diff] [blame] | 142 | struct gsm_subscriber_connection *conn; |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 143 | |
Harald Welte | 2483f1b | 2016-06-19 18:06:02 +0200 | [diff] [blame] | 144 | conn = connection_for_subscr(vsub); |
Holger Hans Peter Freyther | b2be195 | 2010-06-16 13:23:55 +0800 | [diff] [blame] | 145 | if (!conn) |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 146 | return -EINVAL; |
| 147 | |
Harald Welte | 83579ca | 2009-12-29 11:17:18 +0100 | [diff] [blame] | 148 | /* did we actually establish a silent call for this guy? */ |
Holger Hans Peter Freyther | 68884aa | 2010-03-23 06:41:45 +0100 | [diff] [blame] | 149 | if (!conn->silent_call) |
Harald Welte | 83579ca | 2009-12-29 11:17:18 +0100 | [diff] [blame] | 150 | return -EINVAL; |
| 151 | |
Neels Hofmeyr | e2f24d5 | 2017-05-08 15:12:20 +0200 | [diff] [blame] | 152 | #if BEFORE_MSCSPLIT |
| 153 | /* Re-enable this log output once we can obtain this information via |
| 154 | * A-interface, see OS#2391. */ |
Jacob Erlbeck | 8e68b56 | 2014-01-30 21:01:12 +0100 | [diff] [blame] | 155 | DEBUGPC(DLSMS, "Stopping silent call using Timeslot %u on ARFCN %u\n", |
| 156 | conn->lchan->ts->nr, conn->lchan->ts->trx->arfcn); |
Neels Hofmeyr | e2f24d5 | 2017-05-08 15:12:20 +0200 | [diff] [blame] | 157 | #endif |
Jacob Erlbeck | 8e68b56 | 2014-01-30 21:01:12 +0100 | [diff] [blame] | 158 | |
Holger Hans Peter Freyther | 4049455 | 2010-06-28 17:09:29 +0800 | [diff] [blame] | 159 | conn->silent_call = 0; |
Neels Hofmeyr | 6166f29 | 2017-11-22 14:33:12 +0100 | [diff] [blame] | 160 | msc_subscr_conn_put(conn, MSC_CONN_USE_SILENT_CALL); |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 161 | |
| 162 | return 0; |
| 163 | } |