Merge branch 'openthread/default_dnsserver_address' into 'master'

openthread: Add menuconfig to set the default dns server address

See merge request espressif/esp-idf!23581

components/openthread/Kconfig

@@ -179,6 +179,13 @@ menu "OpenThread"
         help
             Select this option to acquire NAT64 address from dns servers.
 
+    config OPENTHREAD_DNS_SERVER_ADDR
+        string "DNS server address (IPv4)"
+        depends on OPENTHREAD_DNS64_CLIENT
+        default "8.8.8.8"
+        help
+            Set the DNS server IPv4 address.
+
     config OPENTHREAD_UART_BUFFER_SIZE
         int "The uart received buffer size of openthread"
         depends on OPENTHREAD_ENABLED

components/openthread/include/esp_openthread_dns64.h

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2022-2023 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -13,6 +13,28 @@
 extern "C" {
 #endif
 
+/**
+ * @brief This function initiizes the dns64 client.
+ *
+ * @return
+ *      - ESP_OK on success
+ *      - ESP_FAIL if OpenThread state changed callback fails to be registered
+ *
+ */
+esp_err_t esp_openthread_dns64_client_init(void);
+
+/**
+ * @brief This function acquires the DNS server address.
+ *
+ * @param[out] dnsserver_addr      The dns server address.
+ *
+ * @return
+ *      - ESP_OK on sussess
+ *      - ESP_ERR_INVALID_ARG if dnsserver_addr is NULL
+ *      - ESP_ERR_INVALID_STATE if dns sever address not available
+ */
+esp_err_t esp_openthread_get_dnsserver_addr(ip6_addr_t *dnsserver_addr);
+
 /**
  * @brief This function acquires the NAT64 prefix in the Thread network.
  *

components/openthread/include/esp_openthread_types.h

@@ -37,6 +37,7 @@ typedef enum {
     OPENTHREAD_EVENT_TREL_ADD_IP6,              /*!< OpenThread stack added TREL IPv6 address */
     OPENTHREAD_EVENT_TREL_REMOVE_IP6,           /*!< OpenThread stack removed TREL IPv6 address */
     OPENTHREAD_EVENT_TREL_MULTICAST_GROUP_JOIN, /*!< OpenThread stack joined TREL IPv6 multicast group */
+    OPENTHREAD_EVENT_SET_DNS_SERVER,            /*!< OpenThread stack set DNS server >*/
 } esp_openthread_event_t;
 
 /**

components/openthread/port/esp_openthread.cpp

@@ -8,6 +8,7 @@
 #include "esp_check.h"
 #include "esp_openthread_border_router.h"
 #include "esp_openthread_common_macro.h"
+#include "esp_openthread_dns64.h"
 #include "esp_openthread_lock.h"
 #include "esp_openthread_platform.h"
 #include "esp_openthread_task_queue.h"
@@ -25,6 +26,10 @@ esp_err_t esp_openthread_init(const esp_openthread_platform_config_t *config)
     esp_openthread_lock_acquire(portMAX_DELAY);
     ESP_RETURN_ON_FALSE(otInstanceInitSingle() != NULL, ESP_FAIL, OT_PLAT_LOG_TAG,
                         "Failed to initialize OpenThread instance");
+#if CONFIG_OPENTHREAD_DNS64_CLIENT
+    ESP_RETURN_ON_ERROR(esp_openthread_dns64_client_init(), OT_PLAT_LOG_TAG,
+                        "Failed to initialize OpenThread dns64 client");
+#endif
     esp_openthread_lock_release();
 
     return ESP_OK;

components/openthread/port/esp_openthread_dns64.c

@@ -1,18 +1,62 @@
 /*
- * SPDX-FileCopyrightText: 2022 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2022-2023 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
 
 #include "esp_openthread_dns64.h"
 
+#include "esp_check.h"
+#include "esp_event.h"
 #include "esp_log.h"
 #include "openthread/instance.h"
 #include "openthread/netdata.h"
 #include "lwip_default_hooks.h"
 #include "lwip/api.h"
+#include "lwip/dns.h"
 
 #define TAG "OT_DNS64"
+// The network data change callback sets the dns server address of index 0, while the CLI sets the dns server address of index 1.
+#define OPENTHREAD_DNS_SERVER_INDEX 0
+
+static void esp_openthread_netdata_change_callback(otChangedFlags changed_flags, void *ctx)
+{
+    if (OT_CHANGED_THREAD_NETDATA & changed_flags) {
+        ip_addr_t dns_server_addr = *IP_ADDR_ANY;
+        if (esp_openthread_get_nat64_prefix(&dns_server_addr.u_addr.ip6) == ESP_OK) {
+            dns_server_addr.type = IPADDR_TYPE_V6;
+            dns_server_addr.u_addr.ip6.addr[3] = ipaddr_addr(CONFIG_OPENTHREAD_DNS_SERVER_ADDR);
+            const ip_addr_t *dnsserver = dns_getserver(OPENTHREAD_DNS_SERVER_INDEX);
+            if (memcmp(dnsserver, &dns_server_addr, sizeof(ip_addr_t)) != 0) {
+                ESP_LOGI(TAG, "Set dns server address: %s", ipaddr_ntoa(&dns_server_addr));
+                dns_setserver(OPENTHREAD_DNS_SERVER_INDEX, &dns_server_addr);
+                if (esp_event_post(OPENTHREAD_EVENT, OPENTHREAD_EVENT_SET_DNS_SERVER, NULL, 0, 0) != ESP_OK) {
+                    ESP_LOGE(TAG, "Failed to post OpenThread set DNS server event");
+                }
+            }
+        }
+    }
+}
+
+esp_err_t esp_openthread_dns64_client_init(void)
+{
+    otInstance *instance = esp_openthread_get_instance();
+    ESP_RETURN_ON_FALSE(otSetStateChangedCallback(instance, esp_openthread_netdata_change_callback, NULL) ==
+                            OT_ERROR_NONE,
+                        ESP_FAIL, TAG, "Failed to install network data change callback");
+    dns_setserver(OPENTHREAD_DNS_SERVER_INDEX, NULL);
+    return ESP_OK;
+}
+
+esp_err_t esp_openthread_get_dnsserver_addr(ip6_addr_t *dnsserver_addr)
+{
+    const ip_addr_t *dnsserver = dns_getserver(OPENTHREAD_DNS_SERVER_INDEX);
+    ESP_RETURN_ON_FALSE(dnsserver_addr, ESP_ERR_INVALID_ARG, TAG, "dnsserver_addr cannot be NULL");
+    ESP_RETURN_ON_FALSE(!ip_addr_isany(dnsserver), ESP_ERR_INVALID_STATE, TAG,
+                        "DNS server address is not set");
+    memcpy(dnsserver_addr, &dnsserver->u_addr.ip6, sizeof(ip6_addr_t));
+    return ESP_OK;
+}
 
 esp_err_t esp_openthread_get_nat64_prefix(ip6_addr_t *nat64_prefix)
 {