diff -Nur lwip-gz-addr/src/include/lwip/priv/tcp_priv.h lwip-qtuple/src/include/lwip/priv/tcp_priv.h
--- lwip-gz-addr/src/include/lwip/priv/tcp_priv.h	2023-12-04 14:08:00.672481010 +0800
+++ lwip-qtuple/src/include/lwip/priv/tcp_priv.h	2023-12-11 11:19:34.552481010 +0800
@@ -347,24 +347,12 @@
   LWIP_ASSERT("Invalid parameter", pcb != NULL);
 
   struct gazelle_quintuple qtuple;
-  if (IP_IS_V4_VAL(pcb->local_ip)) {
-      qtuple.protocol   = 0;
-      qtuple.src_ip     = ip_2_ip4(&pcb->local_ip)->addr;
-      qtuple.src_port   = lwip_htons(pcb->local_port);
-      qtuple.dst_ip     = ip_2_ip4(&pcb->remote_ip)->addr;
-      qtuple.dst_port   = lwip_htons(pcb->remote_port);
-  } else {
-#if LWIP_IPV6
-      qtuple.protocol   = 1;
-      qtuple.src_port   = lwip_htons(pcb->local_port);
-      qtuple.dst_port   = lwip_htons(pcb->remote_port);
 
-      for (int i = 0; i < 4; i++) {
-          qtuple.src_ip6[i] = pcb->local_ip.u_addr.ip6.addr[i];
-          qtuple.dst_ip6[i] = pcb->remote_ip.u_addr.ip6.addr[i];
-      }
-#endif
-  }
+  qtuple.protocol   = IP_IS_V4_VAL(pcb->local_ip) ? GZ_ADDR_TYPE_V4 : GZ_ADDR_TYPE_V6;
+  qtuple.src_ip     = *((gz_addr_t *)&pcb->local_ip);
+  qtuple.src_port   = lwip_htons(pcb->local_port);
+  qtuple.dst_ip     = *((gz_addr_t *)&pcb->remote_ip);
+  qtuple.dst_port   = lwip_htons(pcb->remote_port);
 
 #if GAZELLE_TCP_REUSE_IPPORT
   if (reg_type == REG_RING_TCP_CONNECT_CLOSE) {
diff -Nur lwip-gz-addr/src/include/reg_sock.h lwip-qtuple/src/include/reg_sock.h
--- lwip-gz-addr/src/include/reg_sock.h	2023-12-06 19:41:19.792481010 +0800
+++ lwip-qtuple/src/include/reg_sock.h	2023-12-11 16:17:59.860481010 +0800
@@ -37,6 +37,16 @@
 
 #include "lwipopts.h"
 
+/*  compatible with lwip_ip_addr_type */
+enum gz_ip_addr_type {
+  /** IPv4 */
+  GZ_ADDR_TYPE_V4 =   0U,
+  /** IPv6 */
+  GZ_ADDR_TYPE_V6 =   6U,
+  /** IPv4+IPv6 ("dual-stack") */
+  GZ_ADDR_TYPE_ANY = 46U
+};
+
 /*  compatible with ip4_addr_t */
 struct gz_ip4 {
   uint32_t addr;
@@ -78,13 +88,8 @@
     uint16_t src_port;
     uint16_t dst_port;
 
-    /* TODO: replace with gz_addr_t */
-    uint32_t src_ip;
-    uint32_t dst_ip;
-#if LWIP_IPV6
-    uint32_t src_ip6[4];
-    uint32_t dst_ip6[4];
-#endif
+    gz_addr_t src_ip;
+    gz_addr_t dst_ip;
 };
 
 struct reg_ring_msg {