osmux: Remember the allocated CID and make sure it is released
There appears to be a leak of CIDs:
<000b> mgcp_osmux.c:544 All Osmux circuits are in use!
There are paths that a CID had been requested and never released
of the NAT. Remember the allocated CID inside the endpoint so it
can always be released. It is using a new variable as the behavior
for the NAT and MGCP MGW is different.
The allocated_cid must be signed so that we can assign outside
of the 0-255 range of it.
Fixes: OW#1493
diff --git a/openbsc/include/openbsc/mgcp_internal.h b/openbsc/include/openbsc/mgcp_internal.h
index 1f83659..db22bcf 100644
--- a/openbsc/include/openbsc/mgcp_internal.h
+++ b/openbsc/include/openbsc/mgcp_internal.h
@@ -192,6 +192,8 @@
/* Osmux state: disabled, activating, active */
enum osmux_state state;
/* Allocated Osmux circuit ID for this endpoint */
+ int allocated_cid;
+ /* Used Osmux circuit ID for this endpoint */
uint8_t cid;
/* handle to batch messages */
struct osmux_in_handle *in;
diff --git a/openbsc/include/openbsc/osmux.h b/openbsc/include/openbsc/osmux.h
index 88d045b..82b8fa3 100644
--- a/openbsc/include/openbsc/osmux.h
+++ b/openbsc/include/openbsc/osmux.h
@@ -14,6 +14,8 @@
int osmux_enable_endpoint(struct mgcp_endpoint *endp, int role,
struct in_addr *addr, uint16_t port);
void osmux_disable_endpoint(struct mgcp_endpoint *endp);
+void osmux_allocate_cid(struct mgcp_endpoint *endp);
+void osmux_release_cid(struct mgcp_endpoint *endp);
int osmux_xfrm_to_rtp(struct mgcp_endpoint *endp, int type, char *buf, int rc);
int osmux_xfrm_to_osmux(int type, char *buf, int rc, struct mgcp_endpoint *endp);