diff --git a/sys/netinet/ip_fw.h b/sys/netinet/ip_fw.h
index 4d3099a781a..e09646d6047 100644
--- a/sys/netinet/ip_fw.h
+++ b/sys/netinet/ip_fw.h
@@ -141,6 +141,28 @@ typedef struct _ip_fw3_opheader {
 #define	IP_FW_NAT64CLAT_STATS	164	/* Get NAT64CLAT instance statistics */
 #define	IP_FW_NAT64CLAT_RESET_STATS 165	/* Reset NAT64CLAT instance statistics */
 
+#define	IP_FW_SYNC_XCONFIG	171	/* Create/modify sync instance */
+#define	IP_FW_SYNC_DESTROY	172	/* Destroys sync instance */
+#define	IP_FW_SYNC_XGETCONFIG	173	/* Get sync instance config */
+#define	IP_FW_SYNC_LIST		174	/* List of exported states */
+#define	IP_FW_SYNC_START	175	/* Start of sync service */
+#define	IP_FW_SYNC_STOP		176	/* Stop of sync service */
+
+struct ipfw_sync_cfg {
+	char		name[64];
+	u_char		mode;
+	u_char		addrs;
+	struct cfg_addr {
+		union {
+			struct sockaddr		addr;
+			struct sockaddr_in	ip4;
+			struct sockaddr_in6	ip6;
+		};
+	}		addr[3];
+};
+#define CFG_SYNC_EDGE			1
+#define CFG_SYNC_COLLECTOR		2
+
 /*
  * The kernel representation of ipfw rules is made of a list of
  * 'instructions' (for all practical purposes equivalent to BPF