| /* Implementation for MSC decisions which interface to send messages out on. */ |
| |
| /* (C) 2016 by sysmocom s.m.f.c GmbH <info@sysmocom.de> |
| * |
| * All Rights Reserved |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU Affero General Public License as published by |
| * the Free Software Foundation; either version 3 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU Affero General Public License for more details. |
| * |
| * You should have received a copy of the GNU Affero General Public License |
| * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| #include <osmocom/core/logging.h> |
| |
| #include <openbsc/debug.h> |
| #include <openbsc/gsm_data.h> |
| #include <openbsc/msc_ifaces.h> |
| #include <openbsc/iu.h> |
| #include <openbsc/gsm_subscriber.h> |
| #include <openbsc/transaction.h> |
| #include <openbsc/mgcp.h> |
| #include <openbsc/mgcpgw_client.h> |
| #include <openbsc/vlr.h> |
| |
| #include "../../bscconfig.h" |
| |
| #ifdef BUILD_IU |
| extern struct msgb *ranap_new_msg_rab_assign_voice(uint8_t rab_id, |
| uint32_t rtp_ip, |
| uint16_t rtp_port, |
| bool use_x213_nsap); |
| #endif /* BUILD_IU */ |
| |
| static int msc_tx(struct gsm_subscriber_connection *conn, struct msgb *msg) |
| { |
| DEBUGP(DMSC, "msc_tx %u bytes to %s via %s\n", |
| msg->len, vlr_subscr_name(conn->vsub), |
| ran_type_name(conn->via_ran)); |
| switch (conn->via_ran) { |
| case RAN_GERAN_A: |
| msg->dst = conn; |
| return a_tx(msg); |
| |
| case RAN_UTRAN_IU: |
| msg->dst = conn->iu.ue_ctx; |
| return iu_tx(msg, 0); |
| |
| default: |
| LOGP(DMSC, LOGL_ERROR, |
| "msc_tx(): conn->via_ran invalid (%d)\n", |
| conn->via_ran); |
| return -1; |
| } |
| } |
| |
| |
| int msc_tx_dtap(struct gsm_subscriber_connection *conn, |
| struct msgb *msg) |
| { |
| return msc_tx(conn, msg); |
| } |
| |
| |
| /* 9.2.5 CM service accept */ |
| int msc_gsm48_tx_mm_serv_ack(struct gsm_subscriber_connection *conn) |
| { |
| struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 SERV ACC"); |
| struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh)); |
| |
| gh->proto_discr = GSM48_PDISC_MM; |
| gh->msg_type = GSM48_MT_MM_CM_SERV_ACC; |
| |
| DEBUGP(DMM, "-> CM SERVICE ACCEPT %s\n", |
| vlr_subscr_name(conn->vsub)); |
| |
| return msc_tx_dtap(conn, msg); |
| } |
| |
| /* 9.2.6 CM service reject */ |
| int msc_gsm48_tx_mm_serv_rej(struct gsm_subscriber_connection *conn, |
| enum gsm48_reject_value value) |
| { |
| struct msgb *msg; |
| conn->received_cm_service_request = false; |
| |
| msg = gsm48_create_mm_serv_rej(value); |
| if (!msg) { |
| LOGP(DMM, LOGL_ERROR, "Failed to allocate CM Service Reject.\n"); |
| return -1; |
| } |
| |
| DEBUGP(DMM, "-> CM SERVICE Reject cause: %d\n", value); |
| |
| return msc_tx_dtap(conn, msg); |
| } |
| |
| int msc_tx_common_id(struct gsm_subscriber_connection *conn) |
| { |
| /* Common ID is only sent over IuCS */ |
| if (conn->via_ran != RAN_UTRAN_IU) { |
| LOGP(DMM, LOGL_INFO, |
| "%s: Asked to transmit Common ID, but skipping" |
| " because this is not on UTRAN\n", |
| vlr_subscr_name(conn->vsub)); |
| return 0; |
| } |
| |
| DEBUGP(DIUCS, "%s: tx CommonID %s\n", |
| vlr_subscr_name(conn->vsub), conn->vsub->imsi); |
| return iu_tx_common_id(conn->iu.ue_ctx, conn->vsub->imsi); |
| } |
| |
| #ifdef BUILD_IU |
| static void iu_rab_act_cs(struct ue_conn_ctx *uectx, uint8_t rab_id, |
| uint32_t rtp_ip, uint16_t rtp_port) |
| { |
| struct msgb *msg; |
| bool use_x213_nsap; |
| uint32_t conn_id = uectx->conn_id; |
| |
| use_x213_nsap = (uectx->rab_assign_addr_enc == NSAP_ADDR_ENC_X213); |
| |
| LOGP(DIUCS, LOGL_DEBUG, "Assigning RAB: conn_id=%u, rab_id=%d," |
| " rtp=%x:%u, use_x213_nsap=%d\n", conn_id, rab_id, rtp_ip, |
| rtp_port, use_x213_nsap); |
| |
| msg = ranap_new_msg_rab_assign_voice(rab_id, rtp_ip, rtp_port, |
| use_x213_nsap); |
| msg->l2h = msg->data; |
| |
| if (iu_rab_act(uectx, msg)) |
| LOGP(DIUCS, LOGL_ERROR, "Failed to send RAB Assignment:" |
| " conn_id=%d rab_id=%d rtp=%x:%u\n", |
| conn_id, rab_id, rtp_ip, rtp_port); |
| } |
| |
| static void mgcp_response_rab_act_cs_crcx(struct mgcp_response *r, void *priv) |
| { |
| struct gsm_trans *trans = priv; |
| struct gsm_subscriber_connection *conn = trans->conn; |
| struct ue_conn_ctx *uectx = conn->iu.ue_ctx; |
| uint32_t rtp_ip; |
| int rc; |
| |
| if (r->head.response_code != 200) { |
| LOGP(DMGCP, LOGL_ERROR, |
| "MGCPGW response yields error: %d %s\n", |
| r->head.response_code, r->head.comment); |
| goto rab_act_cs_error; |
| } |
| |
| rc = mgcp_response_parse_params(r); |
| if (rc) { |
| LOGP(DMGCP, LOGL_ERROR, |
| "Cannot parse MGCP response, for %s\n", |
| vlr_subscr_name(trans->vsub)); |
| goto rab_act_cs_error; |
| } |
| |
| conn->iu.mgcp_rtp_port_cn = r->audio_port; |
| |
| rtp_ip = mgcpgw_client_remote_addr_n(conn->network->mgcpgw.client); |
| iu_rab_act_cs(uectx, conn->iu.rab_id, rtp_ip, |
| conn->iu.mgcp_rtp_port_ue); |
| /* use_x213_nsap == 0 for ip.access nano3G */ |
| |
| rab_act_cs_error: |
| /* FIXME abort call, invalidate conn, ... */ |
| return; |
| } |
| |
| static int conn_iu_rab_act_cs(struct gsm_trans *trans) |
| { |
| struct gsm_subscriber_connection *conn = trans->conn; |
| struct mgcpgw_client *mgcp = conn->network->mgcpgw.client; |
| struct msgb *msg; |
| |
| /* HACK. where to scope the RAB Id? At the conn / subscriber / |
| * ue_conn_ctx? */ |
| static uint8_t next_rab_id = 1; |
| conn->iu.rab_id = next_rab_id ++; |
| |
| conn->iu.mgcp_rtp_endpoint = |
| mgcpgw_client_next_endpoint(conn->network->mgcpgw.client); |
| /* HACK: the addresses should be known from CRCX response |
| * and config. */ |
| conn->iu.mgcp_rtp_port_ue = 4000 + 2 * conn->iu.mgcp_rtp_endpoint; |
| |
| /* Establish the RTP stream first as looping back to the originator. |
| * The MDCX will patch through to the counterpart. TODO: play a ring |
| * tone instead. */ |
| msg = mgcp_msg_crcx(mgcp, conn->iu.mgcp_rtp_endpoint, trans->callref, |
| MGCP_CONN_LOOPBACK); |
| return mgcpgw_client_tx(mgcp, msg, mgcp_response_rab_act_cs_crcx, trans); |
| } |
| #endif |
| |
| int msc_call_assignment(struct gsm_trans *trans) |
| { |
| struct gsm_subscriber_connection *conn = trans->conn; |
| |
| switch (conn->via_ran) { |
| case RAN_GERAN_A: |
| LOGP(DMSC, LOGL_ERROR, |
| "msc_call_assignment(): A-interface BSSMAP Assignment" |
| " Request not yet implemented\n"); |
| return -ENOTSUP; |
| |
| case RAN_UTRAN_IU: |
| #ifdef BUILD_IU |
| return conn_iu_rab_act_cs(trans); |
| #else |
| LOGP(DMSC, LOGL_ERROR, |
| "msc_call_assignment(): cannot send RAB Activation, built without Iu support\n"); |
| return -ENOTSUP; |
| #endif |
| |
| default: |
| LOGP(DMSC, LOGL_ERROR, |
| "msc_tx(): conn->via_ran invalid (%d)\n", |
| conn->via_ran); |
| return -EINVAL; |
| } |
| } |
| |
| static void mgcp_response_bridge_mdcx(struct mgcp_response *r, void *priv); |
| |
| static void mgcp_bridge(struct gsm_trans *from, struct gsm_trans *to, |
| enum bridge_state state, |
| enum mgcp_connection_mode mode) |
| { |
| struct gsm_subscriber_connection *conn1 = from->conn; |
| struct gsm_subscriber_connection *conn2 = to->conn; |
| struct mgcpgw_client *mgcp = conn1->network->mgcpgw.client; |
| const char *ip; |
| struct msgb *msg; |
| |
| OSMO_ASSERT(mgcp); |
| |
| from->bridge.peer = to; |
| from->bridge.state = state; |
| |
| /* Loop back to the same MGCP GW */ |
| ip = mgcpgw_client_remote_addr_str(mgcp); |
| |
| msg = mgcp_msg_mdcx(mgcp, |
| conn1->iu.mgcp_rtp_endpoint, |
| ip, conn2->iu.mgcp_rtp_port_cn, |
| mode); |
| if (mgcpgw_client_tx(mgcp, msg, mgcp_response_bridge_mdcx, from)) |
| LOGP(DMGCP, LOGL_ERROR, |
| "Failed to send MDCX message for %s\n", |
| vlr_subscr_name(from->vsub)); |
| } |
| |
| static void mgcp_response_bridge_mdcx(struct mgcp_response *r, void *priv) |
| { |
| struct gsm_trans *trans = priv; |
| struct gsm_trans *peer = trans->bridge.peer; |
| |
| switch (trans->bridge.state) { |
| case BRIDGE_STATE_LOOPBACK_PENDING: |
| trans->bridge.state = BRIDGE_STATE_LOOPBACK_ESTABLISHED; |
| |
| switch (peer->bridge.state) { |
| case BRIDGE_STATE_LOOPBACK_PENDING: |
| /* Wait until the other is done as well. */ |
| return; |
| case BRIDGE_STATE_LOOPBACK_ESTABLISHED: |
| /* Now that both are in loopback, switch both to |
| * forwarding. */ |
| mgcp_bridge(trans, peer, BRIDGE_STATE_BRIDGE_PENDING, |
| MGCP_CONN_RECV_SEND); |
| mgcp_bridge(peer, trans, BRIDGE_STATE_BRIDGE_PENDING, |
| MGCP_CONN_RECV_SEND); |
| break; |
| default: |
| LOGP(DMGCP, LOGL_ERROR, |
| "Unexpected bridge state: %d for %s\n", |
| trans->bridge.state, vlr_subscr_name(trans->vsub)); |
| break; |
| } |
| break; |
| |
| case BRIDGE_STATE_BRIDGE_PENDING: |
| trans->bridge.state = BRIDGE_STATE_BRIDGE_ESTABLISHED; |
| break; |
| |
| default: |
| LOGP(DMGCP, LOGL_ERROR, |
| "Unexpected bridge state: %d for %s\n", |
| trans->bridge.state, vlr_subscr_name(trans->vsub)); |
| break; |
| } |
| } |
| |
| int msc_call_bridge(struct gsm_trans *trans1, struct gsm_trans *trans2) |
| { |
| /* First setup as loopback and configure the counterparts' endpoints, |
| * so that when transmission starts the originating addresses are |
| * already known to be valid. The mgcp callback will continue. */ |
| mgcp_bridge(trans1, trans2, BRIDGE_STATE_LOOPBACK_PENDING, |
| MGCP_CONN_LOOPBACK); |
| mgcp_bridge(trans2, trans1, BRIDGE_STATE_LOOPBACK_PENDING, |
| MGCP_CONN_LOOPBACK); |
| |
| return 0; |
| } |