reference count tracking table entries

src/modules/proto_radius/track.c

@@ -126,10 +126,16 @@ int fr_radius_tracking_entry_delete(fr_tracking_t *ft, fr_tracking_entry_t *entr
 
 	if (entry->timestamp == 0) return -1;
 
+	rad_assert(entry->uses > 0);
+	entry->uses--;
+
 	/*
 	 *	Someone else is using it, so we don't delete it.
 	 */
-	if (recv_time != entry->timestamp) return 0;
+	if (recv_time != entry->timestamp) {
+		if (entry->uses == 0) goto delete;
+		return 0;
+	}
 
 	/*
 	 *	Mark the reply (if any) as done.
@@ -143,6 +149,12 @@ int fr_radius_tracking_entry_delete(fr_tracking_t *ft, fr_tracking_entry_t *entr
 	rad_assert(entry->ev == NULL);
 	entry->timestamp = 0;
 
+	/*
+	 *	Don't delete it.  Someone else is still using it.
+	 */
+	if (entry->uses > 0) return 0;
+
+delete:
 	/*
 	 *	We are tracking src/dst ip/port, we have to remove
 	 *	this entry from the tracking tree, and then free it.
@@ -199,6 +211,7 @@ fr_tracking_status_t fr_radius_tracking_entry_insert(fr_tracking_entry_t **p_ent
 
 		entry->ft = ft;
 		entry->timestamp = timestamp;
+		entry->uses = 1;
 
 		/*
 		 *	Copy the src_dst information over to the entry.
@@ -234,19 +247,16 @@ fr_tracking_status_t fr_radius_tracking_entry_insert(fr_tracking_entry_t **p_ent
 	 *	Over-write an existing entry.
 	 */
 	entry->timestamp = timestamp;
+	entry->uses++;
 
 	/*
-	 *	Toss the conflicting packet (for now).
+	 *	The new packet conflicts with the old one.  Allow BOTH
+	 *	to operate, and let the caller figure out what to do.
 	 */
 	if (entry->reply_len == 0) {
 		return FR_TRACKING_CONFLICTING;
 	}
 
-	/*
-	 *	Over-write an existing entry.
-	 */
-	entry->timestamp = timestamp;
-
 	if (entry->reply) {
 		talloc_const_free(entry->reply);
 		entry->reply = NULL;

src/modules/proto_radius/track.h

@@ -47,6 +47,7 @@ typedef struct fr_tracking_entry_t {
 
 	size_t			src_dst_size;   //!< size of the data in src_dst
 	fr_time_t		timestamp;	//!< when the request was received
+	int			uses;		//!< how many packets are using us
 	uint8_t const		*reply;		//!< the response (if any);
 	size_t			reply_len;	//!< the length of the response
 	uint8_t			data[20];	//!< the full RADIUS packet header