| /* GSM 08.08 like API for OpenBSC. The bridge from MSC to BSC */ |
| |
| /* (C) 2010 by Holger Hans Peter Freyther |
| * (C) 2010 by On Waves |
| * (C) 2009 by Harald Welte <laforge@gnumonks.org> |
| * |
| * 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 <openbsc/bsc_api.h> |
| #include <openbsc/bsc_rll.h> |
| #include <openbsc/gsm_data.h> |
| #include <openbsc/signal.h> |
| #include <openbsc/abis_rsl.h> |
| #include <openbsc/chan_alloc.h> |
| #include <openbsc/handover.h> |
| #include <openbsc/debug.h> |
| |
| #include <osmocore/talloc.h> |
| |
| static LLIST_HEAD(sub_connections); |
| |
| static void rll_ind_cb(struct gsm_lchan *, uint8_t, void *, enum bsc_rllr_ind); |
| static void send_sapi_reject(struct gsm_subscriber_connection *conn, int link_id); |
| |
| struct gsm_subscriber_connection *subscr_con_allocate(struct gsm_lchan *lchan) |
| { |
| struct gsm_subscriber_connection *conn; |
| |
| conn = talloc_zero(lchan->ts->trx->bts->network, struct gsm_subscriber_connection); |
| if (!conn) |
| return NULL; |
| |
| /* Configure the time and start it so it will be closed */ |
| conn->lchan = lchan; |
| conn->bts = lchan->ts->trx->bts; |
| lchan->conn = conn; |
| llist_add_tail(&conn->entry, &sub_connections); |
| return conn; |
| } |
| |
| /* TODO: move subscriber put here... */ |
| void subscr_con_free(struct gsm_subscriber_connection *conn) |
| { |
| struct gsm_lchan *lchan; |
| |
| |
| if (!conn) |
| return; |
| |
| |
| if (conn->subscr) { |
| subscr_put(conn->subscr); |
| conn->subscr = NULL; |
| } |
| |
| |
| if (conn->ho_lchan) |
| LOGP(DNM, LOGL_ERROR, "The ho_lchan should have been cleared.\n"); |
| |
| llist_del(&conn->entry); |
| |
| lchan = conn->lchan; |
| talloc_free(conn); |
| |
| if (lchan) |
| lchan->conn = NULL; |
| } |
| |
| int bsc_api_init(struct gsm_network *network, struct bsc_api *api) |
| { |
| network->bsc_api = api; |
| return 0; |
| } |
| |
| int gsm0808_submit_dtap(struct gsm_subscriber_connection *conn, |
| struct msgb *msg, int link_id) |
| { |
| uint8_t sapi = link_id & 0x7; |
| msg->lchan = conn->lchan; |
| msg->trx = msg->lchan->ts->trx; |
| |
| msg->l3h = msg->data; |
| if (conn->lchan->sapis[sapi] == LCHAN_SAPI_UNUSED) { |
| OBSC_LINKID_CB(msg) = link_id; |
| if (rll_establish(msg->lchan, sapi, rll_ind_cb, msg) != 0) { |
| msgb_free(msg); |
| send_sapi_reject(conn, link_id); |
| return -1; |
| } |
| return 0; |
| } else { |
| return rsl_data_request(msg, link_id); |
| } |
| } |
| |
| /** |
| * Send a GSM08.08 Assignment Request. Right now this does not contain the |
| * audio codec type or the allowed rates for the config. |
| */ |
| int gsm0808_assign_req(struct gsm_subscriber_connection *conn, int chan_type, int audio) |
| { |
| struct bsc_api *api; |
| api = conn->bts->network->bsc_api; |
| |
| api->assign_fail(conn, 0); |
| return 0; |
| } |
| |
| int gsm0808_page(struct gsm_bts *bts, unsigned int page_group, unsigned int mi_len, |
| uint8_t *mi, int chan_type) |
| { |
| return rsl_paging_cmd(bts, page_group, mi_len, mi, chan_type); |
| } |
| |
| /* dequeue messages to layer 4 */ |
| int bsc_upqueue(struct gsm_network *net) |
| { |
| struct gsm_mncc *mncc; |
| struct msgb *msg; |
| int work = 0; |
| |
| if (net) |
| while ((msg = msgb_dequeue(&net->upqueue))) { |
| mncc = (struct gsm_mncc *)msg->data; |
| if (net->mncc_recv) |
| net->mncc_recv(net, mncc->msg_type, mncc); |
| work = 1; /* work done */ |
| talloc_free(msg); |
| } |
| |
| return work; |
| } |
| |
| int gsm0408_rcvmsg(struct msgb *msg, uint8_t link_id) |
| { |
| int rc; |
| struct bsc_api *api = msg->lchan->ts->trx->bts->network->bsc_api; |
| struct gsm_lchan *lchan; |
| |
| lchan = msg->lchan; |
| if (lchan->state != LCHAN_S_ACTIVE) { |
| LOGP(DRSL, LOGL_ERROR, "Got data in non active state. discarding.\n"); |
| return -1; |
| } |
| |
| |
| if (lchan->conn) { |
| api->dtap(lchan->conn, msg); |
| } else { |
| rc = BSC_API_CONN_POL_REJECT; |
| lchan->conn = subscr_con_allocate(msg->lchan); |
| |
| if (lchan->conn) |
| rc = api->compl_l3(lchan->conn, msg, 0); |
| |
| if (rc != BSC_API_CONN_POL_ACCEPT) { |
| subscr_con_free(lchan->conn); |
| lchan_release(lchan, 0, 0); |
| } |
| } |
| |
| return 0; |
| } |
| |
| int gsm0808_cipher_mode(struct gsm_subscriber_connection *conn, int cipher, |
| uint8_t *key, int len) |
| { |
| return -1; |
| } |
| |
| /* |
| * Release all occupied RF Channels but stay around for more. |
| */ |
| int gsm0808_clear(struct gsm_subscriber_connection *conn) |
| { |
| if (conn->ho_lchan) |
| bsc_clear_handover(conn); |
| |
| if (conn->lchan) { |
| lchan_release(conn->lchan, 1, 0); |
| conn->lchan->conn = NULL; |
| } |
| |
| conn->lchan = NULL; |
| conn->ho_lchan = NULL; |
| conn->bts = NULL; |
| |
| return 0; |
| } |
| |
| static void send_sapi_reject(struct gsm_subscriber_connection *conn, int link_id) |
| { |
| struct bsc_api *api; |
| |
| if (!conn) |
| return; |
| |
| api = conn->bts->network->bsc_api; |
| if (!api || !api->sapi_n_reject) |
| return; |
| |
| api->sapi_n_reject(conn, link_id); |
| } |
| |
| static void rll_ind_cb(struct gsm_lchan *lchan, uint8_t link_id, void *_data, enum bsc_rllr_ind rllr_ind) |
| { |
| struct msgb *msg = _data; |
| |
| switch (rllr_ind) { |
| case BSC_RLLR_IND_EST_CONF: |
| rsl_data_request(msg, OBSC_LINKID_CB(msg)); |
| break; |
| case BSC_RLLR_IND_REL_IND: |
| case BSC_RLLR_IND_ERR_IND: |
| case BSC_RLLR_IND_TIMEOUT: |
| send_sapi_reject(lchan->conn, OBSC_LINKID_CB(msg)); |
| msgb_free(msg); |
| break; |
| } |
| } |
| |
| static int bsc_handle_lchan_signal(unsigned int subsys, unsigned int signal, |
| void *handler_data, void *signal_data) |
| { |
| struct bsc_api *bsc; |
| struct gsm_lchan *lchan; |
| struct gsm_subscriber_connection *conn; |
| |
| if (subsys != SS_LCHAN || signal != S_LCHAN_UNEXPECTED_RELEASE) |
| return 0; |
| |
| lchan = (struct gsm_lchan *)signal_data; |
| if (!lchan || !lchan->conn) |
| return 0; |
| |
| bsc = lchan->ts->trx->bts->network->bsc_api; |
| if (!bsc) |
| return 0; |
| |
| conn = lchan->conn; |
| if (bsc->clear_request) |
| bsc->clear_request(conn, 0); |
| |
| /* now give up all channels */ |
| if (conn->lchan == lchan) |
| conn->lchan = NULL; |
| if (conn->ho_lchan == lchan) |
| conn->ho_lchan = NULL; |
| gsm0808_clear(conn); |
| |
| return 0; |
| } |
| |
| static __attribute__((constructor)) void on_dso_load_bsc(void) |
| { |
| register_signal_handler(SS_LCHAN, bsc_handle_lchan_signal, NULL); |
| } |