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Diffstat (limited to 'src/libmsc/ussd.c')
-rw-r--r-- | src/libmsc/ussd.c | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/src/libmsc/ussd.c b/src/libmsc/ussd.c new file mode 100644 index 000000000..f12c1f281 --- /dev/null +++ b/src/libmsc/ussd.c @@ -0,0 +1,95 @@ +/* Network-specific handling of mobile-originated USSDs. */ + +/* (C) 2008-2009 by Harald Welte <laforge@gnumonks.org> + * (C) 2008, 2009 by Holger Hans Peter Freyther <zecke@selfish.org> + * (C) 2009 by Mike Haben <michael.haben@btinternet.com> + * + * 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/>. + * + */ + +/* This module defines the network-specific handling of mobile-originated + USSD messages. */ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <errno.h> + +#include <openbsc/gsm_04_80.h> +#include <openbsc/gsm_subscriber.h> +#include <openbsc/debug.h> +#include <openbsc/osmo_msc.h> + +/* Declarations of USSD strings to be recognised */ +const char USSD_TEXT_OWN_NUMBER[] = "*#100#"; + +/* Forward declarations of network-specific handler functions */ +static int send_own_number(struct gsm_subscriber_connection *conn, const struct msgb *msg, const struct ss_request *req); + + +/* Entrypoint - handler function common to all mobile-originated USSDs */ +int handle_rcv_ussd(struct gsm_subscriber_connection *conn, struct msgb *msg) +{ + int rc; + struct ss_request req; + struct gsm48_hdr *gh; + + memset(&req, 0, sizeof(req)); + gh = msgb_l3(msg); + rc = gsm0480_decode_ss_request(gh, msgb_l3len(msg), &req); + if (!rc) { + DEBUGP(DMM, "Unhandled SS\n"); + rc = gsm0480_send_ussd_reject(conn, msg, &req); + msc_release_connection(conn); + return rc; + } + + /* Interrogation or releaseComplete? */ + if (req.ussd_text[0] == '\0' || req.ussd_text[0] == 0xFF) { + if (req.ss_code > 0) { + /* Assume interrogateSS or modification of it and reject */ + rc = gsm0480_send_ussd_reject(conn, msg, &req); + msc_release_connection(conn); + return rc; + } + /* Still assuming a Release-Complete and returning */ + return 0; + } + + if (!strcmp(USSD_TEXT_OWN_NUMBER, (const char *)req.ussd_text)) { + DEBUGP(DMM, "USSD: Own number requested\n"); + rc = send_own_number(conn, msg, &req); + } else { + DEBUGP(DMM, "Unhandled USSD %s\n", req.ussd_text); + rc = gsm0480_send_ussd_reject(conn, msg, &req); + } + + /* check if we can release it */ + msc_release_connection(conn); + return rc; +} + +/* A network-specific handler function */ +static int send_own_number(struct gsm_subscriber_connection *conn, const struct msgb *msg, const struct ss_request *req) +{ + char *own_number = conn->subscr->extension; + char response_string[GSM_EXTENSION_LENGTH + 20]; + + /* Need trailing CR as EOT character */ + snprintf(response_string, sizeof(response_string), "Your extension is %s\r", own_number); + return gsm0480_send_ussd_response(conn, msg, response_string, req); +} |