net/nat: Add foreach interface for entries

Prepare for netlink conntrack dump of entries.

Signed-off-by: Zhe Weng <wengzhe@xiaomi.com>

net/nat/ipv4_nat_entry.c

@@ -195,32 +195,25 @@ static void ipv4_nat_entry_delete(FAR ipv4_nat_entry_t *entry)
  ****************************************************************************/
 
 #if CONFIG_NET_NAT_ENTRY_RECLAIM_SEC > 0
+static void ipv4_nat_reclaim_entry_cb(FAR ipv4_nat_entry_t *entry,
+                                      FAR void *arg)
+{
+  int32_t current_time = *(FAR int32_t *)arg;
+
+  if (entry->expire_time - current_time <= 0)
+    {
+      ipv4_nat_entry_delete(entry);
+    }
+}
+
 static void ipv4_nat_reclaim_entry(int32_t current_time)
 {
   static int32_t next_reclaim_time = CONFIG_NET_NAT_ENTRY_RECLAIM_SEC;
 
   if (next_reclaim_time - current_time <= 0)
     {
-      FAR hash_node_t *p;
-      FAR hash_node_t *tmp;
-      int count = 0;
-      int i;
-
       ninfo("INFO: Reclaiming all expired NAT44 entries.\n");
-
+      ipv4_nat_entry_foreach(ipv4_nat_reclaim_entry_cb, &current_time);
-      hashtable_for_every_safe(g_nat44_inbound, p, tmp, i)
-        {
-          FAR ipv4_nat_entry_t *entry =
-            container_of(p, ipv4_nat_entry_t, hash_inbound);
-
-          if (entry->expire_time - current_time <= 0)
-            {
-              ipv4_nat_entry_delete(entry);
-              count++;
-            }
-        }
-
-      ninfo("INFO: %d expired NAT44 entries reclaimed.\n", count);
       next_reclaim_time = current_time + CONFIG_NET_NAT_ENTRY_RECLAIM_SEC;
     }
 }
@@ -228,6 +221,26 @@ static void ipv4_nat_reclaim_entry(int32_t current_time)
 #  define ipv4_nat_reclaim_entry(t)
 #endif
 
+/****************************************************************************
+ * Name: ipv4_nat_entry_clear_cb
+ *
+ * Description:
+ *   Clear an entry related to dev. Called when NAT will be disabled on
+ *   any device.
+ *
+ ****************************************************************************/
+
+static void ipv4_nat_entry_clear_cb(FAR ipv4_nat_entry_t *entry,
+                                    FAR void *arg)
+{
+  FAR struct net_driver_s *dev = arg;
+
+  if (net_ipv4addr_cmp(entry->external_ip, dev->d_ipaddr))
+    {
+      ipv4_nat_entry_delete(entry);
+    }
+}
+
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
@@ -248,22 +261,35 @@ static void ipv4_nat_reclaim_entry(int32_t current_time)
  ****************************************************************************/
 
 void ipv4_nat_entry_clear(FAR struct net_driver_s *dev)
+{
+  ninfo("INFO: Clearing all NAT44 entries for %s\n", dev->d_ifname);
+  ipv4_nat_entry_foreach(ipv4_nat_entry_clear_cb, dev);
+}
+
+/****************************************************************************
+ * Name: ipv4_nat_entry_foreach
+ *
+ * Description:
+ *   Call the callback function for each NAT entry.
+ *
+ * Input Parameters:
+ *   cb  - The callback function.
+ *   arg - The argument to pass to the callback function.
+ *
+ ****************************************************************************/
+
+void ipv4_nat_entry_foreach(ipv4_nat_entry_cb_t cb, FAR void *arg)
 {
   FAR hash_node_t *p;
   FAR hash_node_t *tmp;
   int i;
 
-  ninfo("INFO: Clearing all NAT44 entries for %s\n", dev->d_ifname);
-
   hashtable_for_every_safe(g_nat44_inbound, p, tmp, i)
     {
       FAR ipv4_nat_entry_t *entry =
         container_of(p, ipv4_nat_entry_t, hash_inbound);
 
-      if (net_ipv4addr_cmp(entry->external_ip, dev->d_ipaddr))
+      cb(entry, arg);
-        {
-          ipv4_nat_entry_delete(entry);
-        }
     }
 }
 

net/nat/ipv6_nat_entry.c

@@ -188,32 +188,25 @@ static void ipv6_nat_entry_delete(FAR ipv6_nat_entry_t *entry)
  ****************************************************************************/
 
 #if CONFIG_NET_NAT_ENTRY_RECLAIM_SEC > 0
+static void ipv6_nat_reclaim_entry_cb(FAR ipv6_nat_entry_t *entry,
+                                      FAR void *arg)
+{
+  int32_t current_time = *(FAR int32_t *)arg;
+
+  if (entry->expire_time - current_time <= 0)
+    {
+      ipv6_nat_entry_delete(entry);
+    }
+}
+
 static void ipv6_nat_reclaim_entry(int32_t current_time)
 {
   static int32_t next_reclaim_time = CONFIG_NET_NAT_ENTRY_RECLAIM_SEC;
 
   if (next_reclaim_time - current_time <= 0)
     {
-      FAR hash_node_t *p;
-      FAR hash_node_t *tmp;
-      int count = 0;
-      int i;
-
       ninfo("INFO: Reclaiming all expired NAT66 entries.\n");
-
+      ipv6_nat_entry_foreach(ipv6_nat_reclaim_entry_cb, &current_time);
-      hashtable_for_every_safe(g_nat66_inbound, p, tmp, i)
-        {
-          FAR ipv6_nat_entry_t *entry =
-            container_of(p, ipv6_nat_entry_t, hash_inbound);
-
-          if (entry->expire_time - current_time <= 0)
-            {
-              ipv6_nat_entry_delete(entry);
-              count++;
-            }
-        }
-
-      ninfo("INFO: %d expired NAT66 entries reclaimed.\n", count);
       next_reclaim_time = current_time + CONFIG_NET_NAT_ENTRY_RECLAIM_SEC;
     }
 }
@@ -221,6 +214,26 @@ static void ipv6_nat_reclaim_entry(int32_t current_time)
 #  define ipv6_nat_reclaim_entry(t)
 #endif
 
+/****************************************************************************
+ * Name: ipv6_nat_entry_clear_cb
+ *
+ * Description:
+ *   Clear an entry related to dev. Called when NAT will be disabled on
+ *   any device.
+ *
+ ****************************************************************************/
+
+static void ipv6_nat_entry_clear_cb(FAR ipv6_nat_entry_t *entry,
+                                    FAR void *arg)
+{
+  FAR struct net_driver_s *dev = arg;
+
+  if (NETDEV_IS_MY_V6ADDR(dev, entry->external_ip))
+    {
+      ipv6_nat_entry_delete(entry);
+    }
+}
+
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
@@ -241,22 +254,35 @@ static void ipv6_nat_reclaim_entry(int32_t current_time)
  ****************************************************************************/
 
 void ipv6_nat_entry_clear(FAR struct net_driver_s *dev)
+{
+  ninfo("INFO: Clearing all NAT66 entries for %s\n", dev->d_ifname);
+  ipv6_nat_entry_foreach(ipv6_nat_entry_clear_cb, dev);
+}
+
+/****************************************************************************
+ * Name: ipv6_nat_entry_foreach
+ *
+ * Description:
+ *   Call the callback function for each NAT entry.
+ *
+ * Input Parameters:
+ *   cb  - The callback function.
+ *   arg - The argument to pass to the callback function.
+ *
+ ****************************************************************************/
+
+void ipv6_nat_entry_foreach(ipv6_nat_entry_cb_t cb, FAR void *arg)
 {
   FAR hash_node_t *p;
   FAR hash_node_t *tmp;
   int i;
 
-  ninfo("INFO: Clearing all NAT66 entries for %s\n", dev->d_ifname);
-
   hashtable_for_every_safe(g_nat66_inbound, p, tmp, i)
     {
       FAR ipv6_nat_entry_t *entry =
         container_of(p, ipv6_nat_entry_t, hash_inbound);
 
-      if (NETDEV_IS_MY_V6ADDR(dev, entry->external_ip))
+      cb(entry, arg);
-        {
-          ipv6_nat_entry_delete(entry);
-        }
     }
 }
 

net/nat/nat.h

@@ -123,6 +123,11 @@ struct ipv6_nat_entry_s
 typedef struct ipv4_nat_entry_s ipv4_nat_entry_t;
 typedef struct ipv6_nat_entry_s ipv6_nat_entry_t;
 
+typedef CODE void (*ipv4_nat_entry_cb_t)(FAR ipv4_nat_entry_t *entry,
+                                         FAR void *arg);
+typedef CODE void (*ipv6_nat_entry_cb_t)(FAR ipv6_nat_entry_t *entry,
+                                         FAR void *arg);
+
 /* NAT IP/Port manipulate type, to indicate whether to manipulate source or
  * destination IP/Port in a packet.
  */
@@ -281,6 +286,25 @@ uint16_t nat_port_select(FAR struct net_driver_s *dev,
 
 uint32_t nat_expire_time(uint8_t protocol);
 
+/****************************************************************************
+ * Name: ipv4/ipv6_nat_entry_foreach
+ *
+ * Description:
+ *   Call the callback function for each NAT entry.
+ *
+ * Input Parameters:
+ *   cb  - The callback function.
+ *   arg - The argument to pass to the callback function.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_NET_NAT44
+void ipv4_nat_entry_foreach(ipv4_nat_entry_cb_t cb, FAR void *arg);
+#endif
+#ifdef CONFIG_NET_NAT66
+void ipv6_nat_entry_foreach(ipv6_nat_entry_cb_t cb, FAR void *arg);
+#endif
+
 /****************************************************************************
  * Name: ipv4/ipv6_nat_entry_clear
  *