Merge branch 'feature/add_fall_back_dns_config_in_menuconfig_v5.2' in…

…to 'release/v5.2'

feat(lwip): add fall back dns config in menuconfig (v5.2)

See merge request espressif/esp-idf!29154

components/lwip/Kconfig

@@ -130,7 +130,8 @@ menu "LWIP"
         depends on LWIP_ND6
         help
             This option is used to set the the router flag for the NA packets.
-            When enabled, the router flag in NA packet will always set to 1, otherwise, never set router flag for NA packets.
+            When enabled, the router flag in NA packet will always set to 1,
+            otherwise, never set router flag for NA packets.
 
     config LWIP_MAX_SOCKETS
         int "Max number of open sockets"
@@ -706,9 +707,11 @@ menu "LWIP"
                 Control the number of out-of-order pbufs to ensure
                 that the MAC layer has enough RX buffer to receive packets.
 
-                In the Wi-Fi scenario, recommended OOSEQ PBUFS Range: 0 <= TCP_OOSEQ_MAX_PBUFS <= CONFIG_ESP_WIFI_DYNAMIC_RX_BUFFER_NUM/(MAX_TCP_NUMBER + 1)
+                In the Wi-Fi scenario, recommended OOSEQ PBUFS Range:
+                0 <= TCP_OOSEQ_MAX_PBUFS <= CONFIG_ESP_WIFI_DYNAMIC_RX_BUFFER_NUM/(MAX_TCP_NUMBER + 1)
 
-                In the Ethernet scenario,recommended Ethernet OOSEQ PBUFS Range: 0 <= TCP_OOSEQ_MAX_PBUFS <= CONFIG_ETH_DMA_RX_BUFFER_NUM/(MAX_TCP_NUMBER + 1)
+                In the Ethernet scenario,recommended Ethernet OOSEQ PBUFS Range:
+                0 <= TCP_OOSEQ_MAX_PBUFS <= CONFIG_ETH_DMA_RX_BUFFER_NUM/(MAX_TCP_NUMBER + 1)
 
                 Within the recommended value range, the larger the value, the better the performance.
 
@@ -1045,6 +1048,33 @@ menu "LWIP"
 
     endmenu # SNTP
 
+    menu "DNS"
+
+        config LWIP_DNS_MAX_SERVERS
+            int "Maximum number of DNS servers"
+            default 3
+            range 1 4
+            help
+                Set maximum number of DNS servers.
+                If fallback DNS servers are supported,
+                the number of DNS servers needs to be greater than or equal to 3.
+
+        config LWIP_FALLBACK_DNS_SERVER_SUPPORT
+            bool "Enable DNS fallback server support"
+            default n
+            depends on LWIP_DNS_MAX_SERVERS >= 3
+            help
+                Enable this feature to support DNS fallback server.
+
+        config LWIP_FALLBACK_DNS_SERVER_ADDRESS
+            string "DNS fallback server address"
+            default "114.114.114.114"
+            depends on LWIP_FALLBACK_DNS_SERVER_SUPPORT
+            help
+                This option allows you to config dns fallback server address.
+
+    endmenu # DNS
+
     config LWIP_BRIDGEIF_MAX_PORTS
         int "Maximum number of bridge ports"
         default 7

components/lwip/port/include/lwipopts.h

@@ -3,7 +3,7 @@
  *
  * SPDX-License-Identifier: BSD-3-Clause
  *
- * SPDX-FileContributor: 2015-2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileContributor: 2015-2024 Espressif Systems (Shanghai) CO LTD
  */
 #ifndef LWIP_HDR_ESP_LWIPOPTS_H
 #define LWIP_HDR_ESP_LWIPOPTS_H
@@ -472,7 +472,7 @@ static inline uint32_t timeout_from_offered(uint32_t lease, uint32_t min)
 
 /** The maximum of DNS servers
  */
-#define DNS_MAX_SERVERS                 3
+#define DNS_MAX_SERVERS                 CONFIG_LWIP_DNS_MAX_SERVERS
 
 /** ESP specific option only applicable if ESP_DNS=1
  *
@@ -481,6 +481,14 @@ static inline uint32_t timeout_from_offered(uint32_t lease, uint32_t min)
  */
 #define DNS_FALLBACK_SERVER_INDEX       (DNS_MAX_SERVERS - 1)
 
+#ifdef CONFIG_LWIP_FALLBACK_DNS_SERVER_SUPPORT
+#define FALLBACK_DNS_SERVER_ADDRESS(address)                           \
+        do {    ip_addr_t *server_dns = address;                            \
+                char server_ip[] = CONFIG_LWIP_FALLBACK_DNS_SERVER_ADDRESS; \
+                ipaddr_aton(server_ip, server_dns);                         \
+        } while (0)
+#endif /* CONFIG_LWIP_FALLBACK_DNS_SERVER_SUPPORT */
+
 /**
  * LWIP_DNS_SUPPORT_MDNS_QUERIES==1: Enable mDNS queries in hostname resolution.
  * This option is set via menuconfig.
@@ -1576,6 +1584,7 @@ static inline uint32_t timeout_from_offered(uint32_t lease, uint32_t min)
 #define ESP_LWIP_LOCK                   1
 #define ESP_THREAD_PROTECTION           1
 #define LWIP_SUPPORT_CUSTOM_PBUF        1
+#define ESP_LWIP_FALLBACK_DNS_PREFER_IPV4 0
 
 /*
    -----------------------------------------

components/lwip/test_apps/sdkconfig.ci.lwip_debug

@@ -0,0 +1,25 @@
+# Included for build test with LWIP debug enabled.
+
+CONFIG_LWIP_IP_FORWARD=y
+CONFIG_LWIP_IPV4_NAPT=y
+CONFIG_LWIP_DEBUG=y
+CONFIG_LWIP_DEBUG_ESP_LOG=y
+CONFIG_LWIP_NETIF_DEBUG=y
+CONFIG_LWIP_PBUF_DEBUG=y
+CONFIG_LWIP_ETHARP_DEBUG=y
+CONFIG_LWIP_API_LIB_DEBUG=y
+CONFIG_LWIP_SOCKETS_DEBUG=y
+CONFIG_LWIP_IP_DEBUG=y
+CONFIG_LWIP_ICMP_DEBUG=y
+CONFIG_LWIP_DHCP_STATE_DEBUG=y
+CONFIG_LWIP_DHCP_DEBUG=y
+CONFIG_LWIP_IP6_DEBUG=y
+CONFIG_LWIP_ICMP6_DEBUG=y
+CONFIG_LWIP_TCP_DEBUG=y
+CONFIG_LWIP_UDP_DEBUG=y
+CONFIG_LWIP_SNTP_DEBUG=y
+CONFIG_LWIP_DNS_DEBUG=y
+CONFIG_LWIP_NAPT_DEBUG=y
+CONFIG_LWIP_BRIDGEIF_DEBUG=y
+CONFIG_LWIP_BRIDGEIF_FDB_DEBUG=y
+CONFIG_LWIP_BRIDGEIF_FW_DEBUG=y