show capative portal on connect

Signed-off-by: Peter Siegmund <developer@mars3142.org>

firmware/components/api-server/src/api_handlers.c

@@ -627,12 +627,25 @@ static const char *get_mime_type(const char *path)
 esp_err_t api_static_file_handler(httpd_req_t *req)
 {
     char filepath[CONFIG_HTTPD_MAX_URI_LEN + 16];
-    const char *uri = req->uri;
 
-    // Default to index.html for root
-    if (strcmp(uri, "/") == 0)
+    const char *uri = req->uri;
+    wifi_mode_t mode = 0;
+    esp_wifi_get_mode(&mode);
+    // Im AP-Modus immer captive.html ausliefern
+    if (mode == WIFI_MODE_AP || mode == WIFI_MODE_APSTA)
     {
-        uri = "/index.html";
+        if (strcmp(uri, "/") == 0 || strcmp(uri, "/index.html") == 0)
+        {
+            uri = "/captive.html";
+        }
+    }
+    else
+    {
+        // Default to index.html for root
+        if (strcmp(uri, "/") == 0)
+        {
+            uri = "/index.html";
+        }
     }
 
     const char *base_path = CONFIG_API_SERVER_STATIC_FILES_PATH;
@@ -689,10 +702,32 @@ esp_err_t api_captive_portal_handler(httpd_req_t *req)
 {
     ESP_LOGI(TAG, "Captive portal detection: %s", req->uri);
 
-    // Redirect to captive portal page
-    httpd_resp_set_status(req, "302 Found");
-    httpd_resp_set_hdr(req, "Location", "/captive.html");
-    httpd_resp_send(req, NULL, 0);
+    // captive.html direkt ausliefern (Status 200, text/html)
+    const char *base_path = CONFIG_API_SERVER_STATIC_FILES_PATH;
+    char filepath[256];
+    snprintf(filepath, sizeof(filepath), "%s/captive.html", base_path);
+    FILE *f = fopen(filepath, "r");
+    if (!f)
+    {
+        ESP_LOGE(TAG, "captive.html not found: %s", filepath);
+        httpd_resp_set_status(req, "500 Internal Server Error");
+        httpd_resp_sendstr(req, "Captive Portal nicht verfügbar");
+        return ESP_FAIL;
+    }
+    httpd_resp_set_type(req, "text/html");
+    char buf[512];
+    size_t read_bytes;
+    while ((read_bytes = fread(buf, 1, sizeof(buf), f)) > 0)
+    {
+        if (httpd_resp_send_chunk(req, buf, read_bytes) != ESP_OK)
+        {
+            fclose(f);
+            ESP_LOGE(TAG, "Failed to send captive chunk");
+            return ESP_FAIL;
+        }
+    }
+    fclose(f);
+    httpd_resp_send_chunk(req, NULL, 0);
     return ESP_OK;
 }
 

firmware/components/connectivity-manager/CMakeLists.txt

@@ -2,6 +2,7 @@ idf_component_register(SRCS
             src/ble/ble_connection.c
             src/ble/ble_scanner.c
             src/ble_manager.c
+            src/dns_hijack.c
             src/wifi_manager.c
         INCLUDE_DIRS "include"
         REQUIRES

firmware/components/connectivity-manager/include/dns_hijack.h

@@ -0,0 +1,13 @@
+#pragma once
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
+    void dns_server_start(const char *ap_ip);
+    void dns_set_ap_ip(const char *ip);
+
+#ifdef __cplusplus
+}
+#endif

firmware/components/connectivity-manager/src/dns_hijack.c

@@ -0,0 +1,80 @@
+// Minimaler DNS-Server für Captive Portal (alle Anfragen auf AP-IP)
+// Quelle: https://github.com/espressif/esp-idf/blob/master/examples/protocols/sntp/main/dns_server.c (angepasst)
+#include <arpa/inet.h>
+#include <esp_log.h>
+#include <freertos/FreeRTOS.h>
+#include <freertos/task.h>
+#include <lwip/inet.h>
+#include <lwip/sockets.h>
+#include <netinet/in.h>
+#include <string.h>
+#include <sys/socket.h>
+
+#define DNS_PORT 53
+#define DNS_MAX_LEN 512
+static const char *TAG = "dns_hijack";
+
+static char s_ap_ip[16] = "192.168.4.1"; // Default AP-IP, ggf. dynamisch setzen
+
+void dns_set_ap_ip(const char *ip)
+{
+    strncpy(s_ap_ip, ip, sizeof(s_ap_ip) - 1);
+    s_ap_ip[sizeof(s_ap_ip) - 1] = 0;
+}
+
+static void dns_server_task(void *pvParameters)
+{
+    int sock = socket(AF_INET, SOCK_DGRAM, 0);
+    if (sock < 0)
+    {
+        ESP_LOGE(TAG, "Failed to create socket");
+        vTaskDelete(NULL);
+        return;
+    }
+    struct sockaddr_in server_addr = {0};
+    server_addr.sin_family = AF_INET;
+    server_addr.sin_port = htons(DNS_PORT);
+    server_addr.sin_addr.s_addr = htonl(INADDR_ANY);
+    bind(sock, (struct sockaddr *)&server_addr, sizeof(server_addr));
+
+    uint8_t buf[DNS_MAX_LEN];
+    while (1)
+    {
+        struct sockaddr_in from;
+        socklen_t fromlen = sizeof(from);
+        int len = recvfrom(sock, buf, sizeof(buf), 0, (struct sockaddr *)&from, &fromlen);
+        if (len < 0)
+            continue;
+        // DNS Header: 12 bytes, Antwort-Flag setzen
+        buf[2] |= 0x80; // QR=1 (Antwort)
+        buf[3] = 0x80;  // RA=1, RCODE=0
+        // Fragen: 1, Antworten: 1
+        buf[7] = 1;
+        // Antwort anhängen (Name Pointer auf Frage)
+        int qlen = len - 12;
+        int pos = len;
+        buf[pos++] = 0xC0;
+        buf[pos++] = 0x0C; // Name pointer
+        buf[pos++] = 0x00;
+        buf[pos++] = 0x01; // Type A
+        buf[pos++] = 0x00;
+        buf[pos++] = 0x01; // Class IN
+        buf[pos++] = 0x00;
+        buf[pos++] = 0x00;
+        buf[pos++] = 0x00;
+        buf[pos++] = 0x3C; // TTL 60s
+        buf[pos++] = 0x00;
+        buf[pos++] = 0x04; // Data length
+        inet_pton(AF_INET, s_ap_ip, &buf[pos]);
+        pos += 4;
+        sendto(sock, buf, pos, 0, (struct sockaddr *)&from, fromlen);
+    }
+    close(sock);
+    vTaskDelete(NULL);
+}
+
+void dns_server_start(const char *ap_ip)
+{
+    dns_set_ap_ip(ap_ip);
+    xTaskCreate(dns_server_task, "dns_server", 4096, NULL, 3, NULL);
+}

firmware/components/connectivity-manager/src/wifi_manager.c

@@ -1,4 +1,5 @@
 #include "wifi_manager.h"
+#include "dns_hijack.h"
 
 #include "api_server.h"
 
@@ -13,6 +14,7 @@
 #include <led_status.h>
 #include <lwip/err.h>
 #include <lwip/sys.h>
+#include <mdns.h>
 #include <nvs_flash.h>
 #include <sdkconfig.h>
 #include <string.h>
@@ -185,50 +187,33 @@ static void event_handler(void *arg, esp_event_base_t event_base, int32_t event_
 
 void wifi_manager_init()
 {
-#if CONFIG_WIFI_ENABLED
     s_wifi_event_group = xEventGroupCreate();
-    s_current_network_index = 0;
     s_retry_num = 0;
 
     ESP_ERROR_CHECK(esp_netif_init());
-
     ESP_ERROR_CHECK(esp_event_loop_create_default());
-    esp_netif_create_default_wifi_sta();
+
+    // Access Point erstellen
+    esp_netif_create_default_wifi_ap();
 
     wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
     ESP_ERROR_CHECK(esp_wifi_init(&cfg));
 
-    esp_event_handler_instance_t instance_any_id;
-    esp_event_handler_instance_t instance_got_ip;
-    ESP_ERROR_CHECK(
-        esp_event_handler_instance_register(WIFI_EVENT, ESP_EVENT_ANY_ID, &event_handler, NULL, &instance_any_id));
-    ESP_ERROR_CHECK(
-        esp_event_handler_instance_register(IP_EVENT, IP_EVENT_STA_GOT_IP, &event_handler, NULL, &instance_got_ip));
-
-    ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_STA));
+    wifi_config_t ap_config = {.ap = {.ssid = "system-control",
+                                      .ssid_len = strlen("system-control"),
+                                      .password = "",
+                                      .max_connection = 4,
+                                      .authmode = WIFI_AUTH_OPEN}};
+    ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_AP));
+    ESP_ERROR_CHECK(esp_wifi_set_config(WIFI_IF_AP, &ap_config));
     ESP_ERROR_CHECK(esp_wifi_start());
 
-    ESP_DIAG_EVENT(TAG, "WiFi manager initialized with %d network(s), waiting for connection...", s_wifi_network_count);
+    ESP_LOGI(TAG, "Access Point 'system-control' gestartet");
 
-    /* Waiting until either the connection is established (WIFI_CONNECTED_BIT) or
-       connection failed for all networks (WIFI_FAIL_BIT). The bits are set by event_handler() */
-    EventBits_t bits =
-        xEventGroupWaitBits(s_wifi_event_group, WIFI_CONNECTED_BIT | WIFI_FAIL_BIT, pdFALSE, pdFALSE, portMAX_DELAY);
+    // DNS Hijack Server starten (alle DNS-Anfragen auf AP-IP umleiten)
+    dns_server_start("192.168.4.1"); // ggf. dynamisch ermitteln
 
-    if (bits & WIFI_CONNECTED_BIT)
-    {
-        ESP_DIAG_EVENT(TAG, "Connected to AP SSID:%s", s_wifi_networks[s_current_network_index].ssid);
-
-        api_server_config_t s_config = API_SERVER_CONFIG_DEFAULT();
-        ESP_ERROR_CHECK(api_server_start(&s_config));
-    }
-    else if (bits & WIFI_FAIL_BIT)
-    {
-        ESP_LOGE(TAG, "Failed to connect to any configured WiFi network");
-    }
-    else
-    {
-        ESP_LOGE(TAG, "Unexpected event");
-    }
-#endif
+    // API-Server starten
+    api_server_config_t s_config = API_SERVER_CONFIG_DEFAULT();
+    ESP_ERROR_CHECK(api_server_start(&s_config));
 }

firmware/storage/www/captive.html

@@ -13,19 +13,19 @@
 </head>
 
 <body>
-    <div class="header-controls captive-header">
-        <button class="lang-toggle" onclick="toggleLanguage()" aria-label="Sprache wechseln">
-            <span class="lang-flag" id="lang-flag">🇩🇪</span>
-            <span id="lang-label">DE</span>
-        </button>
-        <button class="theme-toggle" onclick="toggleTheme()" aria-label="Theme wechseln">
-            <span class="theme-toggle-icon" id="theme-icon">🌙</span>
-            <span id="theme-label">Dark</span>
-        </button>
-    </div>
 
     <div class="container">
         <div class="header">
+            <div class="header-controls">
+                <button class="lang-toggle" onclick="toggleLanguage()" aria-label="Sprache wechseln">
+                    <span class="lang-flag" id="lang-flag">🇩🇪</span>
+                    <span class="lang-label" id="lang-label">DE</span>
+                </button>
+                <button class="theme-toggle" onclick="toggleTheme()" aria-label="Theme wechseln">
+                    <span class="theme-toggle-icon" id="theme-icon">🌙</span>
+                    <span class="theme-toggle-label" id="theme-label">Dark</span>
+                </button>
+            </div>
             <h1>🚂 System Control</h1>
             <p data-i18n="captive.subtitle">WLAN-Einrichtung</p>
         </div>