move openbsc/* to repos root

This is the first step in creating this repository from the legacy openbsc.git.

Like all other Osmocom repositories, keep the autoconf and automake files in
the repository root. openbsc.git has been the sole exception, which ends now.

Change-Id: I9c6f2a448d9cb1cc088cf1cf6918b69d7e69b4e7

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);
+}