feature: add packet_manager API definition

include/stellar/packet.h

@@ -171,17 +171,8 @@ enum packet_action
 {
     PACKET_ACTION_FORWARD = 0,
     PACKET_ACTION_DROP = 1,
-    PACKET_ACTION_FAST_FORWARD = 2,
-
 };
 
-#include <stdbool.h>
-
-void packet_mark_as_drop(struct packet *pkt, bool drop);
-
-void packet_free(struct packet *pkt);
-
-
 void packet_set_action(struct packet *pkt, enum packet_action action);
 enum packet_action packet_get_action(const struct packet *pkt);
 
@@ -194,6 +185,15 @@ uint16_t packet_get_raw_len(const struct packet *pkt);
 const char *packet_get_payload(const struct packet *pkt);
 uint16_t packet_get_payload_len(const struct packet *pkt);
 
+enum packet_stage
+{
+    PACKET_STAGE_PREROUTING,
+    PACKET_STAGE_INPUT,
+    PACKET_STAGE_FORWARD,
+    PACKET_STAGE_OUTPUT,
+    PACKET_STAGE_POSTROUTING,
+    PACKET_STAGE_MAX,
+};
 
 #ifdef __cplusplus
 }