| /* mncc_builtin.c - default, minimal built-in MNCC Application for |
| * standalone bsc_hack (network-in-the-box mode) */ |
| |
| /* (C) 2008-2010 by Harald Welte <laforge@gnumonks.org> |
| * (C) 2009 by Andreas Eversberg <Andreas.Eversberg@versatel.de> |
| * All Rights Reserved |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 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 General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License along |
| * with this program; if not, write to the Free Software Foundation, Inc., |
| * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| */ |
| |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <errno.h> |
| |
| #include <openbsc/gsm_04_08.h> |
| #include <openbsc/debug.h> |
| #include <openbsc/mncc.h> |
| #include <openbsc/mncc_int.h> |
| #include <osmocom/core/talloc.h> |
| #include <openbsc/gsm_data.h> |
| #include <openbsc/transaction.h> |
| #include <openbsc/rtp_proxy.h> |
| |
| void *tall_call_ctx; |
| |
| static LLIST_HEAD(call_list); |
| |
| static uint32_t new_callref = 0x00000001; |
| |
| struct mncc_int mncc_int = { |
| .def_codec = { GSM48_CMODE_SPEECH_V1, GSM48_CMODE_SPEECH_V1 }, |
| }; |
| |
| static void free_call(struct gsm_call *call) |
| { |
| llist_del(&call->entry); |
| DEBUGP(DMNCC, "(call %x) Call removed.\n", call->callref); |
| talloc_free(call); |
| } |
| |
| |
| static struct gsm_call *get_call_ref(uint32_t callref) |
| { |
| struct gsm_call *callt; |
| |
| llist_for_each_entry(callt, &call_list, entry) { |
| if (callt->callref == callref) |
| return callt; |
| } |
| return NULL; |
| } |
| |
| uint8_t mncc_codec_for_mode(int lchan_type) |
| { |
| /* FIXME: check codec capabilities of the phone */ |
| |
| if (lchan_type != GSM_LCHAN_TCH_H) |
| return mncc_int.def_codec[0]; |
| else |
| return mncc_int.def_codec[1]; |
| } |
| |
| static uint8_t determine_lchan_mode(struct gsm_mncc *setup) |
| { |
| return mncc_codec_for_mode(setup->lchan_type); |
| } |
| |
| /* on incoming call, look up database and send setup to remote subscr. */ |
| static int mncc_setup_ind(struct gsm_call *call, int msg_type, |
| struct gsm_mncc *setup) |
| { |
| struct gsm_mncc mncc; |
| struct gsm_call *remote; |
| |
| memset(&mncc, 0, sizeof(struct gsm_mncc)); |
| mncc.callref = call->callref; |
| |
| /* already have remote call */ |
| if (call->remote_ref) |
| return 0; |
| |
| /* transfer mode 1 would be packet mode, which was never specified */ |
| if (setup->bearer_cap.mode != 0) { |
| LOGP(DMNCC, LOGL_NOTICE, "(call %x) We don't support " |
| "packet mode\n", call->callref); |
| mncc_set_cause(&mncc, GSM48_CAUSE_LOC_PRN_S_LU, |
| GSM48_CC_CAUSE_BEARER_CA_UNAVAIL); |
| goto out_reject; |
| } |
| |
| /* we currently only do speech */ |
| if (setup->bearer_cap.transfer != GSM_MNCC_BCAP_SPEECH) { |
| LOGP(DMNCC, LOGL_NOTICE, "(call %x) We only support " |
| "voice calls\n", call->callref); |
| mncc_set_cause(&mncc, GSM48_CAUSE_LOC_PRN_S_LU, |
| GSM48_CC_CAUSE_BEARER_CA_UNAVAIL); |
| goto out_reject; |
| } |
| |
| /* create remote call */ |
| if (!(remote = talloc_zero(tall_call_ctx, struct gsm_call))) { |
| mncc_set_cause(&mncc, GSM48_CAUSE_LOC_PRN_S_LU, |
| GSM48_CC_CAUSE_RESOURCE_UNAVAIL); |
| goto out_reject; |
| } |
| llist_add_tail(&remote->entry, &call_list); |
| remote->net = call->net; |
| remote->callref = new_callref++; |
| DEBUGP(DMNCC, "(call %x) Creating new remote instance %x.\n", |
| call->callref, remote->callref); |
| |
| /* link remote call */ |
| call->remote_ref = remote->callref; |
| remote->remote_ref = call->callref; |
| |
| /* send call proceeding */ |
| memset(&mncc, 0, sizeof(struct gsm_mncc)); |
| mncc.callref = call->callref; |
| DEBUGP(DMNCC, "(call %x) Accepting call.\n", call->callref); |
| mncc_tx_to_cc(call->net, MNCC_CALL_PROC_REQ, &mncc); |
| |
| /* modify mode */ |
| memset(&mncc, 0, sizeof(struct gsm_mncc)); |
| mncc.callref = call->callref; |
| mncc.lchan_mode = determine_lchan_mode(setup); |
| DEBUGP(DMNCC, "(call %x) Modify channel mode: %s\n", call->callref, |
| get_value_string(gsm48_chan_mode_names, mncc.lchan_mode)); |
| mncc_tx_to_cc(call->net, MNCC_LCHAN_MODIFY, &mncc); |
| |
| /* send setup to remote */ |
| // setup->fields |= MNCC_F_SIGNAL; |
| // setup->signal = GSM48_SIGNAL_DIALTONE; |
| setup->callref = remote->callref; |
| DEBUGP(DMNCC, "(call %x) Forwarding SETUP to remote.\n", call->callref); |
| return mncc_tx_to_cc(remote->net, MNCC_SETUP_REQ, setup); |
| |
| out_reject: |
| mncc_tx_to_cc(call->net, MNCC_REJ_REQ, &mncc); |
| free_call(call); |
| return 0; |
| } |
| |
| static int mncc_alert_ind(struct gsm_call *call, int msg_type, |
| struct gsm_mncc *alert) |
| { |
| struct gsm_call *remote; |
| |
| /* send alerting to remote */ |
| if (!(remote = get_call_ref(call->remote_ref))) |
| return 0; |
| alert->callref = remote->callref; |
| DEBUGP(DMNCC, "(call %x) Forwarding ALERT to remote.\n", call->callref); |
| return mncc_tx_to_cc(remote->net, MNCC_ALERT_REQ, alert); |
| } |
| |
| static int mncc_notify_ind(struct gsm_call *call, int msg_type, |
| struct gsm_mncc *notify) |
| { |
| struct gsm_call *remote; |
| |
| /* send notify to remote */ |
| if (!(remote = get_call_ref(call->remote_ref))) |
| return 0; |
| notify->callref = remote->callref; |
| DEBUGP(DMNCC, "(call %x) Forwarding NOTIF to remote.\n", call->callref); |
| return mncc_tx_to_cc(remote->net, MNCC_NOTIFY_REQ, notify); |
| } |
| |
| static int mncc_setup_cnf(struct gsm_call *call, int msg_type, |
| struct gsm_mncc *connect) |
| { |
| struct gsm_mncc connect_ack, frame_recv; |
| struct gsm_network *net = call->net; |
| struct gsm_call *remote; |
| struct gsm_mncc_bridge bridge = { .msg_type = MNCC_BRIDGE }; |
| |
| /* acknowledge connect */ |
| memset(&connect_ack, 0, sizeof(struct gsm_mncc)); |
| connect_ack.callref = call->callref; |
| DEBUGP(DMNCC, "(call %x) Acknowledge SETUP.\n", call->callref); |
| mncc_tx_to_cc(call->net, MNCC_SETUP_COMPL_REQ, &connect_ack); |
| |
| /* send connect message to remote */ |
| if (!(remote = get_call_ref(call->remote_ref))) |
| return 0; |
| connect->callref = remote->callref; |
| DEBUGP(DMNCC, "(call %x) Sending CONNECT to remote.\n", call->callref); |
| mncc_tx_to_cc(remote->net, MNCC_SETUP_RSP, connect); |
| |
| /* bridge tch */ |
| bridge.callref[0] = call->callref; |
| bridge.callref[1] = call->remote_ref; |
| DEBUGP(DMNCC, "(call %x) Bridging with remote.\n", call->callref); |
| |
| /* in direct mode, we always have to bridge the channels */ |
| if (ipacc_rtp_direct) |
| return mncc_tx_to_cc(call->net, MNCC_BRIDGE, &bridge); |
| |
| /* proxy mode */ |
| if (!net->handover.active) { |
| /* in the no-handover case, we can bridge, i.e. use |
| * the old RTP proxy code */ |
| return mncc_tx_to_cc(call->net, MNCC_BRIDGE, &bridge); |
| } else { |
| /* in case of handover, we need to re-write the RTP |
| * SSRC, sequence and timestamp values and thus |
| * need to enable RTP receive for both directions */ |
| memset(&frame_recv, 0, sizeof(struct gsm_mncc)); |
| frame_recv.callref = call->callref; |
| mncc_tx_to_cc(call->net, MNCC_FRAME_RECV, &frame_recv); |
| frame_recv.callref = call->remote_ref; |
| return mncc_tx_to_cc(call->net, MNCC_FRAME_RECV, &frame_recv); |
| } |
| } |
| |
| static int mncc_disc_ind(struct gsm_call *call, int msg_type, |
| struct gsm_mncc *disc) |
| { |
| struct gsm_call *remote; |
| |
| /* send release */ |
| DEBUGP(DMNCC, "(call %x) Releasing call with cause %d\n", |
| call->callref, disc->cause.value); |
| mncc_tx_to_cc(call->net, MNCC_REL_REQ, disc); |
| |
| /* send disc to remote */ |
| if (!(remote = get_call_ref(call->remote_ref))) { |
| return 0; |
| } |
| disc->callref = remote->callref; |
| DEBUGP(DMNCC, "(call %x) Disconnecting remote with cause %d\n", |
| remote->callref, disc->cause.value); |
| return mncc_tx_to_cc(remote->net, MNCC_DISC_REQ, disc); |
| } |
| |
| static int mncc_rel_ind(struct gsm_call *call, int msg_type, struct gsm_mncc *rel) |
| { |
| struct gsm_call *remote; |
| |
| /* send release to remote */ |
| if (!(remote = get_call_ref(call->remote_ref))) { |
| free_call(call); |
| return 0; |
| } |
| |
| rel->callref = remote->callref; |
| DEBUGP(DMNCC, "(call %x) Releasing remote with cause %d\n", |
| call->callref, rel->cause.value); |
| |
| /* |
| * Release this side of the call right now. Otherwise we end up |
| * in this method for the other call and will also try to release |
| * it and then we will end up with a double free and a crash |
| */ |
| free_call(call); |
| mncc_tx_to_cc(remote->net, MNCC_REL_REQ, rel); |
| |
| return 0; |
| } |
| |
| static int mncc_rel_cnf(struct gsm_call *call, int msg_type, struct gsm_mncc *rel) |
| { |
| free_call(call); |
| return 0; |
| } |
| |
| /* receiving a (speech) traffic frame from the BSC code */ |
| static int mncc_rcv_data(struct gsm_call *call, int msg_type, |
| struct gsm_data_frame *dfr) |
| { |
| struct gsm_trans *remote_trans; |
| |
| remote_trans = trans_find_by_callref(call->net, call->remote_ref); |
| |
| /* this shouldn't really happen */ |
| if (!remote_trans || !remote_trans->conn) { |
| LOGP(DMNCC, LOGL_ERROR, "No transaction or transaction without lchan?!?\n"); |
| return -EIO; |
| } |
| |
| /* RTP socket of remote end has meanwhile died */ |
| if (!remote_trans->conn->lchan->abis_ip.rtp_socket) |
| return -EIO; |
| |
| return rtp_send_frame(remote_trans->conn->lchan->abis_ip.rtp_socket, dfr); |
| } |
| |
| |
| /* Internal MNCC handler input function (from CC -> MNCC -> here) */ |
| int int_mncc_recv(struct gsm_network *net, struct msgb *msg) |
| { |
| void *arg = msgb_data(msg); |
| struct gsm_mncc *data = arg; |
| int msg_type = data->msg_type; |
| int callref; |
| struct gsm_call *call = NULL, *callt; |
| int rc = 0; |
| |
| /* Special messages */ |
| switch(msg_type) { |
| } |
| |
| /* find callref */ |
| callref = data->callref; |
| llist_for_each_entry(callt, &call_list, entry) { |
| if (callt->callref == callref) { |
| call = callt; |
| break; |
| } |
| } |
| |
| /* create callref, if setup is received */ |
| if (!call) { |
| if (msg_type != MNCC_SETUP_IND) |
| goto out_free; /* drop */ |
| /* create call */ |
| if (!(call = talloc_zero(tall_call_ctx, struct gsm_call))) { |
| struct gsm_mncc rel; |
| |
| memset(&rel, 0, sizeof(struct gsm_mncc)); |
| rel.callref = callref; |
| mncc_set_cause(&rel, GSM48_CAUSE_LOC_PRN_S_LU, |
| GSM48_CC_CAUSE_RESOURCE_UNAVAIL); |
| mncc_tx_to_cc(net, MNCC_REL_REQ, &rel); |
| goto out_free; |
| } |
| llist_add_tail(&call->entry, &call_list); |
| call->net = net; |
| call->callref = callref; |
| DEBUGP(DMNCC, "(call %x) Call created.\n", call->callref); |
| } |
| |
| if (mncc_is_data_frame(msg_type)) { |
| rc = mncc_rcv_data(call, msg_type, arg); |
| goto out_free; |
| } |
| |
| DEBUGP(DMNCC, "(call %x) Received message %s\n", call->callref, |
| get_mncc_name(msg_type)); |
| |
| switch(msg_type) { |
| case MNCC_SETUP_IND: |
| rc = mncc_setup_ind(call, msg_type, arg); |
| break; |
| case MNCC_SETUP_CNF: |
| rc = mncc_setup_cnf(call, msg_type, arg); |
| break; |
| case MNCC_SETUP_COMPL_IND: |
| break; |
| case MNCC_CALL_CONF_IND: |
| /* we now need to MODIFY the channel */ |
| data->lchan_mode = determine_lchan_mode(data); |
| mncc_tx_to_cc(call->net, MNCC_LCHAN_MODIFY, data); |
| break; |
| case MNCC_ALERT_IND: |
| rc = mncc_alert_ind(call, msg_type, arg); |
| break; |
| case MNCC_NOTIFY_IND: |
| rc = mncc_notify_ind(call, msg_type, arg); |
| break; |
| case MNCC_DISC_IND: |
| rc = mncc_disc_ind(call, msg_type, arg); |
| break; |
| case MNCC_REL_IND: |
| case MNCC_REJ_IND: |
| rc = mncc_rel_ind(call, msg_type, arg); |
| break; |
| case MNCC_REL_CNF: |
| rc = mncc_rel_cnf(call, msg_type, arg); |
| break; |
| case MNCC_FACILITY_IND: |
| break; |
| case MNCC_START_DTMF_IND: |
| rc = mncc_tx_to_cc(net, MNCC_START_DTMF_REJ, data); |
| break; |
| case MNCC_STOP_DTMF_IND: |
| rc = mncc_tx_to_cc(net, MNCC_STOP_DTMF_RSP, data); |
| break; |
| case MNCC_MODIFY_IND: |
| mncc_set_cause(data, GSM48_CAUSE_LOC_PRN_S_LU, |
| GSM48_CC_CAUSE_SERV_OPT_UNIMPL); |
| DEBUGP(DMNCC, "(call %x) Rejecting MODIFY with cause %d\n", |
| call->callref, data->cause.value); |
| rc = mncc_tx_to_cc(net, MNCC_MODIFY_REJ, data); |
| break; |
| case MNCC_MODIFY_CNF: |
| break; |
| case MNCC_HOLD_IND: |
| mncc_set_cause(data, GSM48_CAUSE_LOC_PRN_S_LU, |
| GSM48_CC_CAUSE_SERV_OPT_UNIMPL); |
| DEBUGP(DMNCC, "(call %x) Rejecting HOLD with cause %d\n", |
| call->callref, data->cause.value); |
| rc = mncc_tx_to_cc(net, MNCC_HOLD_REJ, data); |
| break; |
| case MNCC_RETRIEVE_IND: |
| mncc_set_cause(data, GSM48_CAUSE_LOC_PRN_S_LU, |
| GSM48_CC_CAUSE_SERV_OPT_UNIMPL); |
| DEBUGP(DMNCC, "(call %x) Rejecting RETRIEVE with cause %d\n", |
| call->callref, data->cause.value); |
| rc = mncc_tx_to_cc(net, MNCC_RETRIEVE_REJ, data); |
| break; |
| default: |
| LOGP(DMNCC, LOGL_NOTICE, "(call %x) Message unhandled\n", callref); |
| break; |
| } |
| |
| out_free: |
| msgb_free(msg); |
| |
| return rc; |
| } |