diff options
Diffstat (limited to 'src/osmo-bsc/osmo_bsc_filter.c')
| -rw-r--r-- | src/osmo-bsc/osmo_bsc_filter.c | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/src/osmo-bsc/osmo_bsc_filter.c b/src/osmo-bsc/osmo_bsc_filter.c new file mode 100644 index 000000000..d2735a63a --- /dev/null +++ b/src/osmo-bsc/osmo_bsc_filter.c @@ -0,0 +1,170 @@ +/* (C) 2009-2010 by Holger Hans Peter Freyther <zecke@selfish.org> + * (C) 2009-2010 by On-Waves + * 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 <openbsc/osmo_bsc.h> +#include <openbsc/osmo_msc_data.h> +#include <openbsc/gsm_04_80.h> +#include <openbsc/gsm_subscriber.h> +#include <openbsc/debug.h> +#include <openbsc/paging.h> + +#include <stdlib.h> + +static void handle_lu_request(struct gsm_subscriber_connection *conn, + struct msgb *msg) +{ + struct gsm48_hdr *gh; + struct gsm48_loc_upd_req *lu; + struct gsm48_loc_area_id lai; + struct gsm_network *net; + + if (msgb_l3len(msg) < sizeof(*gh) + sizeof(*lu)) { + LOGP(DMSC, LOGL_ERROR, "LU too small to look at: %u\n", msgb_l3len(msg)); + return; + } + + net = conn->bts->network; + + gh = msgb_l3(msg); + lu = (struct gsm48_loc_upd_req *) gh->data; + + gsm48_generate_lai(&lai, net->country_code, net->network_code, + conn->bts->location_area_code); + + if (memcmp(&lai, &lu->lai, sizeof(lai)) != 0) { + LOGP(DMSC, LOGL_DEBUG, "Marking con for welcome USSD.\n"); + conn->sccp_con->new_subscriber = 1; + } +} + +/* we will need to stop the paging request */ +static int handle_page_resp(struct gsm_subscriber_connection *conn, struct msgb *msg) +{ + uint8_t mi_type; + char mi_string[GSM48_MI_SIZE]; + struct gsm48_hdr *gh; + struct gsm48_pag_resp *resp; + struct gsm_subscriber *subscr; + + if (msgb_l3len(msg) < sizeof(*gh) + sizeof(*resp)) { + LOGP(DMSC, LOGL_ERROR, "PagingResponse too small: %u\n", msgb_l3len(msg)); + return -1; + } + + gh = msgb_l3(msg); + resp = (struct gsm48_pag_resp *) &gh->data[0]; + + gsm48_paging_extract_mi(resp, msgb_l3len(msg) - sizeof(*gh), + mi_string, &mi_type); + DEBUGP(DRR, "PAGING RESPONSE: mi_type=0x%02x MI(%s)\n", + mi_type, mi_string); + + switch (mi_type) { + case GSM_MI_TYPE_TMSI: + subscr = subscr_active_by_tmsi(conn->bts->network, + tmsi_from_string(mi_string)); + break; + case GSM_MI_TYPE_IMSI: + subscr = subscr_active_by_imsi(conn->bts->network, mi_string); + break; + default: + subscr = NULL; + break; + } + + if (!subscr) { + LOGP(DMSC, LOGL_ERROR, "Non active subscriber got paged.\n"); + return -1; + } + + paging_request_stop(conn->bts, subscr, conn, msg); + subscr_put(subscr); + return 0; +} + +/** + * This is used to scan a message for extra functionality of the BSC. This + * includes scanning for location updating requests/acceptd and then send + * a welcome USSD message to the subscriber. + */ +int bsc_scan_bts_msg(struct gsm_subscriber_connection *conn, struct msgb *msg) +{ + struct gsm48_hdr *gh = msgb_l3(msg); + uint8_t pdisc = gh->proto_discr & 0x0f; + uint8_t mtype = gh->msg_type & 0xbf; + + if (pdisc == GSM48_PDISC_MM) { + if (mtype == GSM48_MT_MM_LOC_UPD_REQUEST) + handle_lu_request(conn, msg); + } else if (pdisc == GSM48_PDISC_RR) { + if (mtype == GSM48_MT_RR_PAG_RESP) + handle_page_resp(conn, msg); + } + + return 0; +} + +static void send_welcome_ussd(struct gsm_subscriber_connection *conn) +{ + struct gsm_network *net; + net = conn->bts->network; + + if (!net->msc_data->ussd_welcome_txt) + return; + + gsm0480_send_ussdNotify(conn, 1, net->msc_data->ussd_welcome_txt); + gsm0480_send_releaseComplete(conn); +} + +/** + * Messages coming back from the MSC. + */ +int bsc_scan_msc_msg(struct gsm_subscriber_connection *conn, struct msgb *msg) +{ + struct gsm_network *net; + struct gsm48_loc_area_id *lai; + struct gsm48_hdr *gh; + uint8_t mtype; + + if (msgb_l3len(msg) < sizeof(*gh)) { + LOGP(DMSC, LOGL_ERROR, "GSM48 header does not fit.\n"); + return -1; + } + + gh = (struct gsm48_hdr *) msgb_l3(msg); + mtype = gh->msg_type & 0xbf; + net = conn->bts->network; + + if (mtype == GSM48_MT_MM_LOC_UPD_ACCEPT) { + if (net->msc_data->core_ncc != -1 || + net->msc_data->core_mcc != -1) { + if (msgb_l3len(msg) >= sizeof(*gh) + sizeof(*lai)) { + lai = (struct gsm48_loc_area_id *) &gh->data[0]; + gsm48_generate_lai(lai, net->country_code, + net->network_code, + conn->bts->location_area_code); + } + } + + if (conn->sccp_con->new_subscriber) + send_welcome_ussd(conn); + } + + return 0; +} |