silent_call: remove unfinished fuzzer interface

Remove the fuzzer interface that was partially implemented in
gsm_04_08.c and silent_call.c is causing problems when an
SMS is sent during an active silent call. The reason for this
is that gsm0408_dispatch() in gsm_04_08.c would decide to
rout all uplink traffic to silent_call_rx() in silent_call.c.
silent_call_rx() is a stub function that discards the data.

This patch removes the fuzzer interface code by placing ifdefs
around it, so that it can be re-activated by experimentators.

Change-Id: Id500197d58663b3f4b1756136343670388b0a4bc

openbsc/include/openbsc/silent_call.h

@@ -6,7 +6,10 @@ struct gsm_subscriber_connection;
 extern int gsm_silent_call_start(struct gsm_subscriber *subscr,
                                  void *data, int type);
 extern int gsm_silent_call_stop(struct gsm_subscriber *subscr);
+
+#if 0
 extern int silent_call_rx(struct gsm_subscriber_connection *conn, struct msgb *msg);
 extern int silent_call_reroute(struct gsm_subscriber_connection *conn, struct msgb *msg);
+#endif
 
 #endif /* _SILENT_CALL_H */

openbsc/src/libmsc/gsm_04_08.c

@@ -3958,8 +3958,10 @@ int gsm0408_dispatch(struct gsm_subscriber_connection *conn, struct msgb *msg)
 	OSMO_ASSERT(msg);
 
 	LOGP(DRLL, LOGL_DEBUG, "Dispatching 04.08 message, pdisc=%d\n", pdisc);
+#if 0
 	if (silent_call_reroute(conn, msg))
 		return silent_call_rx(conn, msg);
+#endif
 
 	switch (pdisc) {
 	case GSM48_PDISC_CC:

openbsc/src/libmsc/silent_call.c

@@ -72,6 +72,7 @@ static int paging_cb_silent(unsigned int hooknum, unsigned int event,
 	return rc;
 }
 
+#if 0
 /* receive a layer 3 message from a silent call */
 int silent_call_rx(struct gsm_subscriber_connection *conn, struct msgb *msg)
 {
@@ -79,6 +80,7 @@ int silent_call_rx(struct gsm_subscriber_connection *conn, struct msgb *msg)
 	LOGP(DLSMS, LOGL_NOTICE, "Discarding L3 message from a silent call.\n");
 	return 0;
 }
+#endif
 
 struct msg_match {
 	uint8_t pdisc;
@@ -91,6 +93,7 @@ static const struct msg_match silent_call_accept[] = {
 	{ GSM48_PDISC_MM, GSM48_MT_MM_CM_SERV_REQ },
 };
 
+#if 0
 /* decide if we need to reroute a message as part of a silent call */
 int silent_call_reroute(struct gsm_subscriber_connection *conn, struct msgb *msg)
 {
@@ -114,6 +117,7 @@ int silent_call_reroute(struct gsm_subscriber_connection *conn, struct msgb *msg
 	LOGP(DLSMS, LOGL_INFO, "Rerouting L3 message from a silent call.\n");
 	return 1;
 }
+#endif
 
 
 /* initiate a silent call with a given subscriber */