DHCP Allows selecting the DHCP server's network interface (#426)

examples/access_point/access_point.c

@@ -1,11 +1,11 @@
-/* Very basic example showing usage of access point mode and the DHCP server.
+/**
-
+ * Very basic example showing usage of access point mode and the DHCP server.
-   The ESP in the example runs a telnet server on 172.16.0.1 (port 23) that
+ * The ESP in the example runs a telnet server on 172.16.0.1 (port 23) that
-   outputs some status information if you connect to it, then closes
+ * outputs some status information if you connect to it, then closes
-   the connection.
+ * the connection.
-
+ *
-   This example code is in the public domain.
+ * This example code is in the public domain.
-*/
+ */
 #include <string.h>
 
 #include <espressif/esp_common.h>
@@ -36,44 +36,39 @@ void user_init(void)
     IP4_ADDR(&ap_ip.netmask, 255, 255, 0, 0);
     sdk_wifi_set_ip_info(1, &ap_ip);
 
-    struct sdk_softap_config ap_config = {
+    struct sdk_softap_config ap_config = { .ssid = AP_SSID, .ssid_hidden = 0, .channel = 3, .ssid_len = strlen(AP_SSID), .authmode =
-        .ssid = AP_SSID,
+            AUTH_WPA_WPA2_PSK, .password = AP_PSK, .max_connection = 3, .beacon_interval = 100, };
-        .ssid_hidden = 0,
-        .channel = 3,
-        .ssid_len = strlen(AP_SSID),
-        .authmode = AUTH_WPA_WPA2_PSK,
-        .password = AP_PSK,
-        .max_connection = 3,
-        .beacon_interval = 100,
-    };
     sdk_wifi_softap_set_config(&ap_config);
 
-    ip4_addr_t first_client_ip;
-    IP4_ADDR(&first_client_ip, 172, 16, 0, 2);
-    dhcpserver_start(&first_client_ip, 4);
-
     xTaskCreate(telnetTask, "telnetTask", 512, NULL, 2, NULL);
 }
 
 /* Telnet task listens on port 23, returns some status information and then closes
  the connection if you connect to it.
-*/
+ */
 static void telnetTask(void *pvParameters)
 {
-  struct netconn *nc = netconn_new (NETCONN_TCP);
+    ip_addr_t first_client_ip;
-  if(!nc) {
+    IP4_ADDR(&first_client_ip, 172, 16, 0, 2);
+    dhcpserver_start(sdk_system_get_netif(SOFTAP_IF), &first_client_ip, 4);
+
+    struct netconn *nc = netconn_new(NETCONN_TCP);
+    if (!nc)
+    {
         printf("Status monitor: Failed to allocate socket.\r\n");
         return;
     }
     netconn_bind(nc, IP_ANY_TYPE, TELNET_PORT);
     netconn_listen(nc);
 
-  while(1) {
+    while (1)
+    {
         struct netconn *client = NULL;
         err_t err = netconn_accept(nc, &client);
 
-    if (err != ERR_OK) {
+        if (err != ERR_OK)
-      if(client)
+        {
+            if (client)
                 netconn_delete(client);
             continue;
         }
@@ -83,10 +78,9 @@ static void telnetTask(void *pvParameters)
         netconn_peer(client, &client_addr, &port_ignore);
 
         char buf[80];
-    snprintf(buf, sizeof(buf), "Uptime %d seconds\r\n",
+        snprintf(buf, sizeof(buf), "Uptime %d seconds\r\n", xTaskGetTickCount() * portTICK_PERIOD_MS / 1000);
-	     xTaskGetTickCount()*portTICK_PERIOD_MS/1000);
         netconn_write(client, buf, strlen(buf), NETCONN_COPY);
-    snprintf(buf, sizeof(buf), "Free heap %d bytes\r\n", (int)xPortGetFreeHeapSize());
+        snprintf(buf, sizeof(buf), "Free heap %d bytes\r\n", (int) xPortGetFreeHeapSize());
         netconn_write(client, buf, strlen(buf), NETCONN_COPY);
         char abuf[40];
         snprintf(buf, sizeof(buf), "Your address is %s\r\n\r\n", ipaddr_ntoa_r(&client_addr, abuf, sizeof(abuf)));

extras/dhcpserver/dhcpserver.c

@@ -3,11 +3,7 @@
  * Based on RFC2131 http://www.ietf.org/rfc/rfc2131.txt
  * ... although not fully RFC compliant yet.
  *
- * TODO
+ * Probably allocates more memory than it should, it should be possible to reuse netbufs in most cases.
- * * Allow binding on a single interface only (for mixed AP/client mode), lwip seems to make it hard to
- *   listen for or send broadcasts on a specific interface only.
- *
- * * Probably allocates more memory than it should, it should be possible to reuse netbufs in most cases.
  *
  * Part of esp-open-rtos
  * Copyright (C) 2015 Superhouse Automation Pty Ltd
@@ -92,8 +88,12 @@ inline static void sprintf_ipaddr(const ip4_addr_t *addr, char *dest)
                 ip4_addr2(addr), ip4_addr3(addr), ip4_addr4(addr));
 }
 
-void dhcpserver_start(const ip4_addr_t *first_client_addr, uint8_t max_leases)
+void dhcpserver_start(struct netif *server_if, const ip_addr_t *first_client_addr, uint8_t max_leases)
 {
+    if(!server_if){
+        printf("DHCP Server Error: server_if is NULL.\r\n");
+        return;
+    }
     /* Stop any existing running dhcpserver */
     if (dhcpserver_task_handle)
         dhcpserver_stop();
@@ -109,7 +109,7 @@ void dhcpserver_start(const ip4_addr_t *first_client_addr, uint8_t max_leases)
     ip4_addr_set_zero(&state->router);
     ip4_addr_set_zero(&state->dns);
 
-    xTaskCreate(dhcpserver_task, "DHCP Server", 448, NULL, 2, &dhcpserver_task_handle);
+    xTaskCreate(dhcpserver_task, "DHCPServer", 768, server_if, 8, &dhcpserver_task_handle);
 }
 
 void dhcpserver_stop(void)
@@ -134,7 +134,7 @@ void dhcpserver_set_dns(const ip4_addr_t *dns)
 static void dhcpserver_task(void *pxParameter)
 {
     /* netif_list isn't assigned until after user_init completes, which is why we do it inside the task */
-    state->server_if = netif_list; /* TODO: Make this configurable */
+    state->server_if = pxParameter;
 
     state->nc = netconn_new (NETCONN_UDP);
     if(!state->nc) {
@@ -143,7 +143,7 @@ static void dhcpserver_task(void *pxParameter)
     }
 
     netconn_bind(state->nc, IP4_ADDR_ANY, LWIP_IANA_PORT_DHCP_SERVER);
-    netconn_bind_if (state->nc, netif_get_index(state->server_if));
+    netconn_bind_if(state->nc, netif_get_index(state->server_if));
 
     while(1)
     {

extras/dhcpserver/include/dhcpserver.h

@@ -25,8 +25,10 @@ extern "C" {
    first_client_addr is the IP address of the first lease to be handed
    to a client.  Subsequent lease addresses are calculated by
    incrementing the final octet of the IPv4 address, up to max_leases.
+
+   The server will wait for requests on server_if interface.
 */
-void dhcpserver_start(const ip4_addr_t *first_client_addr, uint8_t max_leases);
+void dhcpserver_start(struct netif *server_if, const ip_addr_t *first_client_addr, uint8_t max_leases);
 
 void dhcpserver_get_lease(const ip4_addr_t *first_client_addr, uint8_t max_leases);
 

tests/cases/04_wifi_basic.c

@@ -40,6 +40,11 @@ DEFINE_TESTCASE(04_wifi_basic, DUAL)
 
 static void server_task(void *pvParameters)
 {
+
+    ip_addr_t first_client_ip;
+    IP4_ADDR(&first_client_ip, 172, 16, 0, 2);
+    dhcpserver_start(sdk_system_get_netif(SOFTAP_IF), &first_client_ip, 4);
+
     char buf[BUF_SIZE];
     struct netconn *nc = netconn_new(NETCONN_TCP);
     TEST_ASSERT_TRUE_MESSAGE(nc != 0, "Failed to allocate socket");
@@ -103,10 +108,6 @@ static void a_04_wifi_basic(void)
     };
     sdk_wifi_softap_set_config(&ap_config);
 
-    ip_addr_t first_client_ip;
-    IP4_ADDR(&first_client_ip, 172, 16, 0, 2);
-    dhcpserver_start(&first_client_ip, 4);
-
     xTaskCreate(server_task, "setver_task", 1024, NULL, 2, NULL);
 }