ESP：来自 OS 的自动 login/accept 消息重定向到 public WIFI 门户接入点之类的页面
ESP: Auto login/accept message by OS with redirect to page like public WIFI portals access points
示例：
我不知道你怎么称呼这个功能，所以我试着解释一下。例如，当您将 phone 连接到 public WiFi hotspot/access 点时，您会收到来自 OS 的消息，要求接受 terms/conditions 或者您需要登录才能使用连接。当您点击此邮件时，它会打开 the/a 浏览器并启动登录页面。
他们是怎么做到的？这是 https 功能吗？
更新：(1)
它被称为强制门户：
强制门户技术强制网络上的 HTTP 客户端在正常使用 Internet 之前查看特殊网页（通常用于身份验证目的）。强制门户将 Web 浏览器变成身份验证设备。这是通过拦截大多数数据包（无论地址或端口）直到用户打开浏览器并尝试访问网络来完成的。那时浏览器被重定向到一个网页，该网页可能需要身份验证 and/or 付款，或者只是显示可接受的使用政策并要求用户同意。许多 Wi-Fi 热点使用强制门户，也可用于控制有线访问（例如公寓、酒店房间、商务中心、"open" 以太网插孔）。
情况：
我想对 ESP (ESP32/ESP8266) 做同样的事情，因为我开发了一个可以通过 WiFi 配置的设备。当用户连接到设备并且不必首先打开浏览器、输入 IP 地址等时，这将是非常用户友好的。只需一条消息，用户可以单击它并启动主页。
在 AP 模式下，我打开了 DNS 并将所有内容重定向到主页，但这不是最佳解决方案（有时也不起作用）。为了让您了解我在做什么，这里有一些代码，我的库的一部分：
bool suStartAccessPointNetwork( String sSSIDNetworkName, String sSSIDPassword,
IPAddress sStaticIpAddress,
uint16_t iDnsPort = 0,
uint8_t iTries = 20,
uint16_t iDelay = 500
)
{
WiFi.disconnect();
suSetNetworkAccessPointMode();
delay( 1000 );
WiFi.softAPConfig( sStaticIpAddress,
sStaticIpAddress,
IPAddress( 255, 255, 255, 0 )
);
SU_WIFI_AP_ESTABLISHED = WiFi.softAP( sSSIDNetworkName.c_str(), sSSIDPassword.c_str() );
if( iDnsPort > 0 )
{
static SUDNSServer* pDnsServer = NULLPTR;
if( !pDnsServer )
{ pDnsServer = new SUDNSServer(); }
// modify TTL, default is 60 seconds
pDnsServer->setTTL(60);
// set which return code will be used for all other domains (e.g. sending
// ServerFailure instead of NonExistentDomain will reduce number of queries
// sent by clients)
// default is DNSReplyCode::NonExistentDomain
pDnsServer->setErrorReplyCode( DNSReplyCode::NoError );
pDnsServer->start( iDnsPort,
//SCDMS_MDNS_ACCESS_NAME,
"*",
sStaticIpAddress
);
Serial.print("DNS server started at " );
Serial.println( sStaticIpAddress );
suSetDnsServer( pDnsServer );
}
Serial.print("[AP]:");
bool bConnected = false;
if( iTries == 0 )
{ ++iTries; }
// Try to connect, give WiFi 10 seconds to launch a network as access point.
while( !(bConnected = suIsNetworkEstablished()) && (iTries--) )
{
Serial.print('.');
//Serial.print(WiFi.status());
delay(500);
}
if( bConnected )
{ SU_WIFI_AP_ESTABLISHED = bConnected; }
Serial.println( bConnected?" ((o))":" o?" );
return bConnected;
}
问题：
我怎样才能实现上面示例中描述的这种功能？有任何想法吗？有可能吗？
--------------------
更新二：
@gre_gor 提出了我在知道服务名称后也找到的相同示例（另请参阅更新 1）。像示例中那样实现 Url 路径等，如上所述不起作用。好的，尝试了完整的示例，相同的结果，没有 OS popup/message，没有重定向。在浏览器中输入 IP 地址，这与我已经拥有的一样有效。
我试过的扩展演示之一：
#include <ESP8266WiFi.h>
#include <WiFiClient.h>
#include <ESP8266WebServer.h>
#include <DNSServer.h>
#include <ESP8266mDNS.h>
#include <EEPROM.h>
/*
This example serves a "hello world" on a WLAN and a SoftAP at the same time.
The SoftAP allow you to configure WLAN parameters at run time. They are not setup in the sketch but saved on EEPROM.
Connect your computer or cell phone to wifi network ESP_ap with password 12345678. A popup may appear and it allow you to go to WLAN config. If it does not then navigate to http://192.168.4.1/wifi and config it there.
Then wait for the module to connect to your wifi and take note of the WLAN IP it got. Then you can disconnect from ESP_ap and return to your regular WLAN.
Now the ESP8266 is in your network. You can reach it through http://192.168.x.x/ (the IP you took note of) or maybe at http://esp8266.local too.
This is a captive portal because through the softAP it will redirect any http request to http://192.168.4.1/
*/
/* Set these to your desired softAP credentials. They are not configurable at runtime */
#ifndef APSSID
#define APSSID "ESP_ap"
#define APPSK "12345678"
#endif
const char *softAP_ssid = APSSID;
const char *softAP_password = APPSK;
/* hostname for mDNS. Should work at least on windows. Try http://esp8266.local */
const char *myHostname = "esp8266";
/* Don't set this wifi credentials. They are configurated at runtime and stored on EEPROM */
char ssid[32] = "";
char password[32] = "";
// DNS server
const byte DNS_PORT = 53;
DNSServer dnsServer;
// Web server
ESP8266WebServer server(80);
/* Soft AP network parameters */
IPAddress apIP(192, 168, 4, 1);
IPAddress netMsk(255, 255, 255, 0);
/** Should I connect to WLAN asap? */
boolean connect;
/** Last time I tried to connect to WLAN */
unsigned long lastConnectTry = 0;
/** Current WLAN status */
unsigned int status = WL_IDLE_STATUS;
/** Is this an IP? */
boolean isIp(String str) {
for (size_t i = 0; i < str.length(); i++) {
int c = str.charAt(i);
if (c != '.' && (c < '0' || c > '9')) {
return false;
}
}
return true;
}
/** IP to String? */
String toStringIp(IPAddress ip) {
String res = "";
for (int i = 0; i < 3; i++) {
res += String((ip >> (8 * i)) & 0xFF) + ".";
}
res += String(((ip >> 8 * 3)) & 0xFF);
return res;
}
/** Load WLAN credentials from EEPROM */
void loadCredentials() {
EEPROM.begin(512);
EEPROM.get(0, ssid);
EEPROM.get(0 + sizeof(ssid), password);
char ok[2 + 1];
EEPROM.get(0 + sizeof(ssid) + sizeof(password), ok);
EEPROM.end();
if (String(ok) != String("OK")) {
ssid[0] = 0;
password[0] = 0;
}
Serial.println("Recovered credentials:");
Serial.println(ssid);
Serial.println(strlen(password) > 0 ? "********" : "<no password>");
}
/** Store WLAN credentials to EEPROM */
void saveCredentials() {
EEPROM.begin(512);
EEPROM.put(0, ssid);
EEPROM.put(0 + sizeof(ssid), password);
char ok[2 + 1] = "OK";
EEPROM.put(0 + sizeof(ssid) + sizeof(password), ok);
EEPROM.commit();
EEPROM.end();
}
/** Handle root or redirect to captive portal */
void handleRoot() {
if (captivePortal()) { // If caprive portal redirect instead of displaying the page.
return;
}
server.sendHeader("Cache-Control", "no-cache, no-store, must-revalidate");
server.sendHeader("Pragma", "no-cache");
server.sendHeader("Expires", "-1");
String Page;
Page += F(
"<html><head></head><body>"
"<h1>HELLO WORLD!!</h1>");
if (server.client().localIP() == apIP) {
Page += String(F("<p>You are connected through the soft AP: ")) + softAP_ssid + F("</p>");
} else {
Page += String(F("<p>You are connected through the wifi network: ")) + ssid + F("</p>");
}
Page += F(
"<p>You may want to <a href='/wifi'>config the wifi connection</a>.</p>"
"</body></html>");
server.send(200, "text/html", Page);
}
/** Redirect to captive portal if we got a request for another domain. Return true in that case so the page handler do not try to handle the request again. */
boolean captivePortal() {
if (!isIp(server.hostHeader()) && server.hostHeader() != (String(myHostname) + ".local")) {
Serial.println("Request redirected to captive portal");
server.sendHeader("Location", String("http://") + toStringIp(server.client().localIP()), true);
server.send(302, "text/plain", ""); // Empty content inhibits Content-length header so we have to close the socket ourselves.
server.client().stop(); // Stop is needed because we sent no content length
return true;
}
return false;
}
/** Wifi config page handler */
void handleWifi() {
server.sendHeader("Cache-Control", "no-cache, no-store, must-revalidate");
server.sendHeader("Pragma", "no-cache");
server.sendHeader("Expires", "-1");
String Page;
Page += F(
"<html><head></head><body>"
"<h1>Wifi config</h1>");
if (server.client().localIP() == apIP) {
Page += String(F("<p>You are connected through the soft AP: ")) + softAP_ssid + F("</p>");
} else {
Page += String(F("<p>You are connected through the wifi network: ")) + ssid + F("</p>");
}
Page +=
String(F(
"\r\n<br />"
"<table><tr><th align='left'>SoftAP config</th></tr>"
"<tr><td>SSID ")) +
String(softAP_ssid) +
F("</td></tr>"
"<tr><td>IP ") +
toStringIp(WiFi.softAPIP()) +
F("</td></tr>"
"</table>"
"\r\n<br />"
"<table><tr><th align='left'>WLAN config</th></tr>"
"<tr><td>SSID ") +
String(ssid) +
F("</td></tr>"
"<tr><td>IP ") +
toStringIp(WiFi.localIP()) +
F("</td></tr>"
"</table>"
"\r\n<br />"
"<table><tr><th align='left'>WLAN list (refresh if any missing)</th></tr>");
Serial.println("scan start");
int n = WiFi.scanNetworks();
Serial.println("scan done");
if (n > 0) {
for (int i = 0; i < n; i++) {
Page += String(F("\r\n<tr><td>SSID ")) + WiFi.SSID(i) + ((WiFi.encryptionType(i) == ENC_TYPE_NONE) ? F(" ") : F(" *")) + F(" (") + WiFi.RSSI(i) + F(")</td></tr>");
}
} else {
Page += F("<tr><td>No WLAN found</td></tr>");
}
Page += F(
"</table>"
"\r\n<br /><form method='POST' action='wifisave'><h4>Connect to network:</h4>"
"<input type='text' placeholder='network' name='n'/>"
"<br /><input type='password' placeholder='password' name='p'/>"
"<br /><input type='submit' value='Connect/Disconnect'/></form>"
"<p>You may want to <a href='/'>return to the home page</a>.</p>"
"</body></html>");
server.send(200, "text/html", Page);
server.client().stop(); // Stop is needed because we sent no content length
}
/** Handle the WLAN save form and redirect to WLAN config page again */
void handleWifiSave() {
Serial.println("wifi save");
server.arg("n").toCharArray(ssid, sizeof(ssid) - 1);
server.arg("p").toCharArray(password, sizeof(password) - 1);
server.sendHeader("Location", "wifi", true);
server.sendHeader("Cache-Control", "no-cache, no-store, must-revalidate");
server.sendHeader("Pragma", "no-cache");
server.sendHeader("Expires", "-1");
server.send(302, "text/plain", ""); // Empty content inhibits Content-length header so we have to close the socket ourselves.
server.client().stop(); // Stop is needed because we sent no content length
saveCredentials();
connect = strlen(ssid) > 0; // Request WLAN connect with new credentials if there is a SSID
}
void handleNotFound() {
if (captivePortal()) { // If caprive portal redirect instead of displaying the error page.
return;
}
String message = F("File Not Found\n\n");
message += F("URI: ");
message += server.uri();
message += F("\nMethod: ");
message += (server.method() == HTTP_GET) ? "GET" : "POST";
message += F("\nArguments: ");
message += server.args();
message += F("\n");
for (uint8_t i = 0; i < server.args(); i++) {
message += String(F(" ")) + server.argName(i) + F(": ") + server.arg(i) + F("\n");
}
server.sendHeader("Cache-Control", "no-cache, no-store, must-revalidate");
server.sendHeader("Pragma", "no-cache");
server.sendHeader("Expires", "-1");
server.send(404, "text/plain", message);
}
void setup() {
delay(1000);
Serial.begin(9600);
Serial.println();
Serial.println("Configuring access point...");
/* You can remove the password parameter if you want the AP to be open. */
WiFi.softAPConfig(apIP, apIP, netMsk);
WiFi.softAP(softAP_ssid, softAP_password);
delay(500); // Without delay I've seen the IP address blank
Serial.print("AP IP address: ");
Serial.println(WiFi.softAPIP());
/* Setup the DNS server redirecting all the domains to the apIP */
dnsServer.setErrorReplyCode(DNSReplyCode::NoError);
dnsServer.start(DNS_PORT, "*", apIP);
/* Setup web pages: root, wifi config pages, SO captive portal detectors and not found. */
server.on("/", handleRoot);
server.on("/wifi", handleWifi);
server.on("/wifisave", handleWifiSave);
server.on("/generate_204", handleRoot); //Android captive portal. Maybe not needed. Might be handled by notFound handler.
server.on("/fwlink", handleRoot); //Microsoft captive portal. Maybe not needed. Might be handled by notFound handler.
server.onNotFound(handleNotFound);
server.begin(); // Web server start
Serial.println("HTTP server started");
loadCredentials(); // Load WLAN credentials from network
connect = strlen(ssid) > 0; // Request WLAN connect if there is a SSID
}
void connectWifi() {
Serial.println("Connecting as wifi client...");
WiFi.disconnect();
WiFi.begin(ssid, password);
int connRes = WiFi.waitForConnectResult();
Serial.print("connRes: ");
Serial.println(connRes);
}
void loop() {
if (connect) {
Serial.println("Connect requested");
connect = false;
connectWifi();
lastConnectTry = millis();
}
{
unsigned int s = WiFi.status();
if (s == 0 && millis() > (lastConnectTry + 60000)) {
/* If WLAN disconnected and idle try to connect */
/* Don't set retry time too low as retry interfere the softAP operation */
connect = true;
}
if (status != s) { // WLAN status change
Serial.print("Status: ");
Serial.println(s);
status = s;
if (s == WL_CONNECTED) {
/* Just connected to WLAN */
Serial.println("");
Serial.print("Connected to ");
Serial.println(ssid);
Serial.print("IP address: ");
Serial.println(WiFi.localIP());
// Setup MDNS responder
if (!MDNS.begin(myHostname)) {
Serial.println("Error setting up MDNS responder!");
} else {
Serial.println("mDNS responder started");
// Add service to MDNS-SD
MDNS.addService("http", "tcp", 80);
}
} else if (s == WL_NO_SSID_AVAIL) {
WiFi.disconnect();
}
}
if (s == WL_CONNECTED) {
MDNS.update();
}
}
// Do work:
//DNS
dnsServer.processNextRequest();
//HTTP
server.handleClient();
}
找到这个：https://www.esp8266.com/viewtopic.php?f=6&t=15993
eduperez 的这个 post：
"Android devices have the Google DNSs hard-coded, they will always use 8.8.8.8 and 8.8.4.4, despite what the DHPC server might tell them to use. You need to configure your gateway to redirect all outgoing traffic to port 53 to your DNS."
这给出了想法，使用 8.8.8.8 作为 IP 地址和 DNS 服务器地址。
多田！很有魅力！
所以这个草图可以工作：
#include <ESP8266WiFi.h>
#include <WiFiClient.h>
#include <ESP8266WebServer.h>
#include <DNSServer.h>
#include <ESP8266mDNS.h>
#include <EEPROM.h>
/*
This example serves a "hello world" on a WLAN and a SoftAP at the same time.
The SoftAP allow you to configure WLAN parameters at run time. They are not setup in the sketch but saved on EEPROM.
Connect your computer or cell phone to wifi network ESP_ap with password 12345678. A popup may appear and it allow you to go to WLAN config. If it does not then navigate to http://192.168.4.1/wifi and config it there.
Then wait for the module to connect to your wifi and take note of the WLAN IP it got. Then you can disconnect from ESP_ap and return to your regular WLAN.
Now the ESP8266 is in your network. You can reach it through http://192.168.x.x/ (the IP you took note of) or maybe at http://esp8266.local too.
This is a captive portal because through the softAP it will redirect any http request to http://192.168.4.1/
*/
/* Set these to your desired softAP credentials. They are not configurable at runtime */
#ifndef APSSID
#define APSSID "TheGeekMan"
#define APPSK "12345678"
#endif
const char *softAP_ssid = APSSID;
const char *softAP_password = APPSK;
/* hostname for mDNS. Should work at least on windows. Try http://esp8266.local */
const char *myHostname = "thegeekman";
/* Don't set this wifi credentials. They are configurated at runtime and stored on EEPROM */
char ssid[32] = "";
char password[32] = "";
// DNS server
const byte DNS_PORT = 53;
DNSServer dnsServer;
// Web server
ESP8266WebServer server(80);
/* Soft AP network parameters */
//IPAddress apIP(192, 168, 4, 1);
IPAddress apIP(8, 8, 8, 8);
IPAddress netMsk(255, 255, 255, 0);
/** Should I connect to WLAN asap? */
boolean connect;
/** Last time I tried to connect to WLAN */
unsigned long lastConnectTry = 0;
/** Current WLAN status */
unsigned int status = WL_IDLE_STATUS;
/** Is this an IP? */
boolean isIp(String str) {
for (size_t i = 0; i < str.length(); i++) {
int c = str.charAt(i);
if (c != '.' && (c < '0' || c > '9')) {
return false;
}
}
return true;
}
/** IP to String? */
String toStringIp(IPAddress ip) {
String res = "";
for (int i = 0; i < 3; i++) {
res += String((ip >> (8 * i)) & 0xFF) + ".";
}
res += String(((ip >> 8 * 3)) & 0xFF);
return res;
}
/** Load WLAN credentials from EEPROM */
void loadCredentials() {
EEPROM.begin(512);
EEPROM.get(0, ssid);
EEPROM.get(0 + sizeof(ssid), password);
char ok[2 + 1];
EEPROM.get(0 + sizeof(ssid) + sizeof(password), ok);
EEPROM.end();
if (String(ok) != String("OK")) {
ssid[0] = 0;
password[0] = 0;
}
Serial.println("Recovered credentials:");
Serial.println(ssid);
Serial.println(strlen(password) > 0 ? "********" : "<no password>");
}
/** Store WLAN credentials to EEPROM */
void saveCredentials() {
EEPROM.begin(512);
EEPROM.put(0, ssid);
EEPROM.put(0 + sizeof(ssid), password);
char ok[2 + 1] = "OK";
EEPROM.put(0 + sizeof(ssid) + sizeof(password), ok);
EEPROM.commit();
EEPROM.end();
}
/** Handle root or redirect to captive portal */
void handleRoot() {
if (captivePortal()) { // If caprive portal redirect instead of displaying the page.
return;
}
server.sendHeader("Cache-Control", "no-cache, no-store, must-revalidate");
server.sendHeader("Pragma", "no-cache");
server.sendHeader("Expires", "-1");
String Page;
Page += F(
"<html><head></head><body>"
"<h1>HELLO WORLD!!</h1>");
if (server.client().localIP() == apIP) {
Page += String(F("<p>You are connected through the soft AP: ")) + softAP_ssid + F("</p>");
} else {
Page += String(F("<p>You are connected through the wifi network: ")) + ssid + F("</p>");
}
Page += F(
"<p>You may want to <a href='/wifi'>config the wifi connection</a>.</p>"
"</body></html>");
server.send(200, "text/html", Page);
}
/** Redirect to captive portal if we got a request for another domain. Return true in that case so the page handler do not try to handle the request again. */
boolean captivePortal() {
if (!isIp(server.hostHeader()) && server.hostHeader() != (String(myHostname) + ".local")) {
Serial.println("Request redirected to captive portal");
server.sendHeader("Location", String("http://") + toStringIp(server.client().localIP()), true);
server.send(302, "text/plain", ""); // Empty content inhibits Content-length header so we have to close the socket ourselves.
server.client().stop(); // Stop is needed because we sent no content length
return true;
}
return false;
}
/** Wifi config page handler */
void handleWifi() {
server.sendHeader("Cache-Control", "no-cache, no-store, must-revalidate");
server.sendHeader("Pragma", "no-cache");
server.sendHeader("Expires", "-1");
String Page;
Page += F(
"<html><head></head><body>"
"<h1>Wifi config</h1>");
if (server.client().localIP() == apIP) {
Page += String(F("<p>You are connected through the soft AP: ")) + softAP_ssid + F("</p>");
} else {
Page += String(F("<p>You are connected through the wifi network: ")) + ssid + F("</p>");
}
Page +=
String(F(
"\r\n<br />"
"<table><tr><th align='left'>SoftAP config</th></tr>"
"<tr><td>SSID ")) +
String(softAP_ssid) +
F("</td></tr>"
"<tr><td>IP ") +
toStringIp(WiFi.softAPIP()) +
F("</td></tr>"
"</table>"
"\r\n<br />"
"<table><tr><th align='left'>WLAN config</th></tr>"
"<tr><td>SSID ") +
String(ssid) +
F("</td></tr>"
"<tr><td>IP ") +
toStringIp(WiFi.localIP()) +
F("</td></tr>"
"</table>"
"\r\n<br />"
"<table><tr><th align='left'>WLAN list (refresh if any missing)</th></tr>");
Serial.println("scan start");
int n = WiFi.scanNetworks();
Serial.println("scan done");
if (n > 0) {
for (int i = 0; i < n; i++) {
Page += String(F("\r\n<tr><td>SSID ")) + WiFi.SSID(i) + ((WiFi.encryptionType(i) == ENC_TYPE_NONE) ? F(" ") : F(" *")) + F(" (") + WiFi.RSSI(i) + F(")</td></tr>");
}
} else {
Page += F("<tr><td>No WLAN found</td></tr>");
}
Page += F(
"</table>"
"\r\n<br /><form method='POST' action='wifisave'><h4>Connect to network:</h4>"
"<input type='text' placeholder='network' name='n'/>"
"<br /><input type='password' placeholder='password' name='p'/>"
"<br /><input type='submit' value='Connect/Disconnect'/></form>"
"<p>You may want to <a href='/'>return to the home page</a>.</p>"
"</body></html>");
server.send(200, "text/html", Page);
server.client().stop(); // Stop is needed because we sent no content length
}
/** Handle the WLAN save form and redirect to WLAN config page again */
void handleWifiSave() {
Serial.println("wifi save");
server.arg("n").toCharArray(ssid, sizeof(ssid) - 1);
server.arg("p").toCharArray(password, sizeof(password) - 1);
server.sendHeader("Location", "wifi", true);
server.sendHeader("Cache-Control", "no-cache, no-store, must-revalidate");
server.sendHeader("Pragma", "no-cache");
server.sendHeader("Expires", "-1");
server.send(302, "text/plain", ""); // Empty content inhibits Content-length header so we have to close the socket ourselves.
server.client().stop(); // Stop is needed because we sent no content length
saveCredentials();
connect = strlen(ssid) > 0; // Request WLAN connect with new credentials if there is a SSID
}
void handleNotFound() {
if (captivePortal()) { // If caprive portal redirect instead of displaying the error page.
return;
}
String message = F("File Not Found\n\n");
message += F("URI: ");
message += server.uri();
message += F("\nMethod: ");
message += (server.method() == HTTP_GET) ? "GET" : "POST";
message += F("\nArguments: ");
message += server.args();
message += F("\n");
for (uint8_t i = 0; i < server.args(); i++) {
message += String(F(" ")) + server.argName(i) + F(": ") + server.arg(i) + F("\n");
}
server.sendHeader("Cache-Control", "no-cache, no-store, must-revalidate");
server.sendHeader("Pragma", "no-cache");
server.sendHeader("Expires", "-1");
server.send(404, "text/plain", message);
}
void setup() {
delay(1000);
Serial.begin(9600);
Serial.println();
Serial.println("Configuring access point...");
/* You can remove the password parameter if you want the AP to be open. */
WiFi.softAPConfig(apIP, apIP, netMsk);
WiFi.softAP(softAP_ssid, softAP_password);
delay(500); // Without delay I've seen the IP address blank
Serial.print("AP IP address: ");
Serial.println(WiFi.softAPIP());
/* Setup the DNS server redirecting all the domains to the apIP */
dnsServer.setErrorReplyCode(DNSReplyCode::NoError);
dnsServer.start(DNS_PORT, "*", apIP);
/* Setup web pages: root, wifi config pages, SO captive portal detectors and not found. */
server.on("/", handleRoot);
server.on("/wifi", handleWifi);
server.on("/wifisave", handleWifiSave);
server.on("/generate_204", handleRoot); //Android captive portal. Maybe not needed. Might be handled by notFound handler.
server.on("/fwlink", handleRoot); //Microsoft captive portal. Maybe not needed. Might be handled by notFound handler.
server.onNotFound(handleNotFound);
server.begin(); // Web server start
Serial.println("HTTP server started");
loadCredentials(); // Load WLAN credentials from network
connect = strlen(ssid) > 0; // Request WLAN connect if there is a SSID
}
void connectWifi() {
Serial.println("Connecting as wifi client...");
WiFi.disconnect();
WiFi.begin(ssid, password);
int connRes = WiFi.waitForConnectResult();
Serial.print("connRes: ");
Serial.println(connRes);
}
void loop() {
if (connect) {
Serial.println("Connect requested");
connect = false;
connectWifi();
lastConnectTry = millis();
}
{
unsigned int s = WiFi.status();
if (s == 0 && millis() > (lastConnectTry + 60000)) {
/* If WLAN disconnected and idle try to connect */
/* Don't set retry time too low as retry interfere the softAP operation */
connect = true;
}
if (status != s) { // WLAN status change
Serial.print("Status: ");
Serial.println(s);
status = s;
if (s == WL_CONNECTED) {
/* Just connected to WLAN */
Serial.println("");
Serial.print("Connected to ");
Serial.println(ssid);
Serial.print("IP address: ");
Serial.println(WiFi.localIP());
// Setup MDNS responder
if (!MDNS.begin(myHostname)) {
Serial.println("Error setting up MDNS responder!");
} else {
Serial.println("mDNS responder started");
// Add service to MDNS-SD
MDNS.addService("http", "tcp", 80);
}
} else if (s == WL_NO_SSID_AVAIL) {
WiFi.disconnect();
}
}
if (s == WL_CONNECTED) {
MDNS.update();
}
}
// Do work:
//DNS
dnsServer.processNextRequest();
//HTTP
server.handleClient();
}
关键不仅要使用8.8.8.8作为DNS地址，还要为NotFound的情况添加处理程序。我知道它包含在问题代码中，但我发现它对于 android auto-detect 强制门户
是强制性的
在提供 HTTP 服务器时，您通常有两种选择：
- 使用 WebServer class 并设置根处理程序。 HTTP header 的解析和处理由库完成。
- 使用 WifiServer 并接收包含 header 的 HTTP 消息，并自行处理所有内容。
如果您正在做第 1 件事并假装通过连接 Android 设备使用，我建议为显示强制门户的错误情况添加一个处理程序：
server.onNotFound(handleRoot);
我注意到对于 Android 10，要正确检测强制门户并使 phone 显示“触摸以登录网络”消息是必要的。如果不是，您必须导航到任何 HTTP 地址并让 DNS 为您完成工作（不是 HTTPS）。
编辑：事实上，不使用 8.8.8.8 或 8.8.4.4（即使用 192.168.0.1）它对我有用。但我必须包含错误的处理程序 (onNotFound)
示例：
我不知道你怎么称呼这个功能，所以我试着解释一下。例如，当您将 phone 连接到 public WiFi hotspot/access 点时，您会收到来自 OS 的消息，要求接受 terms/conditions 或者您需要登录才能使用连接。当您点击此邮件时，它会打开 the/a 浏览器并启动登录页面。
他们是怎么做到的？这是 https 功能吗？
更新：(1)
它被称为强制门户：
强制门户技术强制网络上的 HTTP 客户端在正常使用 Internet 之前查看特殊网页（通常用于身份验证目的）。强制门户将 Web 浏览器变成身份验证设备。这是通过拦截大多数数据包（无论地址或端口）直到用户打开浏览器并尝试访问网络来完成的。那时浏览器被重定向到一个网页，该网页可能需要身份验证 and/or 付款，或者只是显示可接受的使用政策并要求用户同意。许多 Wi-Fi 热点使用强制门户，也可用于控制有线访问（例如公寓、酒店房间、商务中心、"open" 以太网插孔）。
情况：
我想对 ESP (ESP32/ESP8266) 做同样的事情，因为我开发了一个可以通过 WiFi 配置的设备。当用户连接到设备并且不必首先打开浏览器、输入 IP 地址等时，这将是非常用户友好的。只需一条消息，用户可以单击它并启动主页。
在 AP 模式下，我打开了 DNS 并将所有内容重定向到主页，但这不是最佳解决方案（有时也不起作用）。为了让您了解我在做什么，这里有一些代码，我的库的一部分：
bool suStartAccessPointNetwork( String sSSIDNetworkName, String sSSIDPassword,
IPAddress sStaticIpAddress,
uint16_t iDnsPort = 0,
uint8_t iTries = 20,
uint16_t iDelay = 500
)
{
WiFi.disconnect();
suSetNetworkAccessPointMode();
delay( 1000 );
WiFi.softAPConfig( sStaticIpAddress,
sStaticIpAddress,
IPAddress( 255, 255, 255, 0 )
);
SU_WIFI_AP_ESTABLISHED = WiFi.softAP( sSSIDNetworkName.c_str(), sSSIDPassword.c_str() );
if( iDnsPort > 0 )
{
static SUDNSServer* pDnsServer = NULLPTR;
if( !pDnsServer )
{ pDnsServer = new SUDNSServer(); }
// modify TTL, default is 60 seconds
pDnsServer->setTTL(60);
// set which return code will be used for all other domains (e.g. sending
// ServerFailure instead of NonExistentDomain will reduce number of queries
// sent by clients)
// default is DNSReplyCode::NonExistentDomain
pDnsServer->setErrorReplyCode( DNSReplyCode::NoError );
pDnsServer->start( iDnsPort,
//SCDMS_MDNS_ACCESS_NAME,
"*",
sStaticIpAddress
);
Serial.print("DNS server started at " );
Serial.println( sStaticIpAddress );
suSetDnsServer( pDnsServer );
}
Serial.print("[AP]:");
bool bConnected = false;
if( iTries == 0 )
{ ++iTries; }
// Try to connect, give WiFi 10 seconds to launch a network as access point.
while( !(bConnected = suIsNetworkEstablished()) && (iTries--) )
{
Serial.print('.');
//Serial.print(WiFi.status());
delay(500);
}
if( bConnected )
{ SU_WIFI_AP_ESTABLISHED = bConnected; }
Serial.println( bConnected?" ((o))":" o?" );
return bConnected;
}
问题：
我怎样才能实现上面示例中描述的这种功能？有任何想法吗？有可能吗？
--------------------
更新二：
@gre_gor 提出了我在知道服务名称后也找到的相同示例（另请参阅更新 1）。像示例中那样实现 Url 路径等，如上所述不起作用。好的，尝试了完整的示例，相同的结果，没有 OS popup/message，没有重定向。在浏览器中输入 IP 地址，这与我已经拥有的一样有效。
我试过的扩展演示之一：
#include <ESP8266WiFi.h>
#include <WiFiClient.h>
#include <ESP8266WebServer.h>
#include <DNSServer.h>
#include <ESP8266mDNS.h>
#include <EEPROM.h>
/*
This example serves a "hello world" on a WLAN and a SoftAP at the same time.
The SoftAP allow you to configure WLAN parameters at run time. They are not setup in the sketch but saved on EEPROM.
Connect your computer or cell phone to wifi network ESP_ap with password 12345678. A popup may appear and it allow you to go to WLAN config. If it does not then navigate to http://192.168.4.1/wifi and config it there.
Then wait for the module to connect to your wifi and take note of the WLAN IP it got. Then you can disconnect from ESP_ap and return to your regular WLAN.
Now the ESP8266 is in your network. You can reach it through http://192.168.x.x/ (the IP you took note of) or maybe at http://esp8266.local too.
This is a captive portal because through the softAP it will redirect any http request to http://192.168.4.1/
*/
/* Set these to your desired softAP credentials. They are not configurable at runtime */
#ifndef APSSID
#define APSSID "ESP_ap"
#define APPSK "12345678"
#endif
const char *softAP_ssid = APSSID;
const char *softAP_password = APPSK;
/* hostname for mDNS. Should work at least on windows. Try http://esp8266.local */
const char *myHostname = "esp8266";
/* Don't set this wifi credentials. They are configurated at runtime and stored on EEPROM */
char ssid[32] = "";
char password[32] = "";
// DNS server
const byte DNS_PORT = 53;
DNSServer dnsServer;
// Web server
ESP8266WebServer server(80);
/* Soft AP network parameters */
IPAddress apIP(192, 168, 4, 1);
IPAddress netMsk(255, 255, 255, 0);
/** Should I connect to WLAN asap? */
boolean connect;
/** Last time I tried to connect to WLAN */
unsigned long lastConnectTry = 0;
/** Current WLAN status */
unsigned int status = WL_IDLE_STATUS;
/** Is this an IP? */
boolean isIp(String str) {
for (size_t i = 0; i < str.length(); i++) {
int c = str.charAt(i);
if (c != '.' && (c < '0' || c > '9')) {
return false;
}
}
return true;
}
/** IP to String? */
String toStringIp(IPAddress ip) {
String res = "";
for (int i = 0; i < 3; i++) {
res += String((ip >> (8 * i)) & 0xFF) + ".";
}
res += String(((ip >> 8 * 3)) & 0xFF);
return res;
}
/** Load WLAN credentials from EEPROM */
void loadCredentials() {
EEPROM.begin(512);
EEPROM.get(0, ssid);
EEPROM.get(0 + sizeof(ssid), password);
char ok[2 + 1];
EEPROM.get(0 + sizeof(ssid) + sizeof(password), ok);
EEPROM.end();
if (String(ok) != String("OK")) {
ssid[0] = 0;
password[0] = 0;
}
Serial.println("Recovered credentials:");
Serial.println(ssid);
Serial.println(strlen(password) > 0 ? "********" : "<no password>");
}
/** Store WLAN credentials to EEPROM */
void saveCredentials() {
EEPROM.begin(512);
EEPROM.put(0, ssid);
EEPROM.put(0 + sizeof(ssid), password);
char ok[2 + 1] = "OK";
EEPROM.put(0 + sizeof(ssid) + sizeof(password), ok);
EEPROM.commit();
EEPROM.end();
}
/** Handle root or redirect to captive portal */
void handleRoot() {
if (captivePortal()) { // If caprive portal redirect instead of displaying the page.
return;
}
server.sendHeader("Cache-Control", "no-cache, no-store, must-revalidate");
server.sendHeader("Pragma", "no-cache");
server.sendHeader("Expires", "-1");
String Page;
Page += F(
"<html><head></head><body>"
"<h1>HELLO WORLD!!</h1>");
if (server.client().localIP() == apIP) {
Page += String(F("<p>You are connected through the soft AP: ")) + softAP_ssid + F("</p>");
} else {
Page += String(F("<p>You are connected through the wifi network: ")) + ssid + F("</p>");
}
Page += F(
"<p>You may want to <a href='/wifi'>config the wifi connection</a>.</p>"
"</body></html>");
server.send(200, "text/html", Page);
}
/** Redirect to captive portal if we got a request for another domain. Return true in that case so the page handler do not try to handle the request again. */
boolean captivePortal() {
if (!isIp(server.hostHeader()) && server.hostHeader() != (String(myHostname) + ".local")) {
Serial.println("Request redirected to captive portal");
server.sendHeader("Location", String("http://") + toStringIp(server.client().localIP()), true);
server.send(302, "text/plain", ""); // Empty content inhibits Content-length header so we have to close the socket ourselves.
server.client().stop(); // Stop is needed because we sent no content length
return true;
}
return false;
}
/** Wifi config page handler */
void handleWifi() {
server.sendHeader("Cache-Control", "no-cache, no-store, must-revalidate");
server.sendHeader("Pragma", "no-cache");
server.sendHeader("Expires", "-1");
String Page;
Page += F(
"<html><head></head><body>"
"<h1>Wifi config</h1>");
if (server.client().localIP() == apIP) {
Page += String(F("<p>You are connected through the soft AP: ")) + softAP_ssid + F("</p>");
} else {
Page += String(F("<p>You are connected through the wifi network: ")) + ssid + F("</p>");
}
Page +=
String(F(
"\r\n<br />"
"<table><tr><th align='left'>SoftAP config</th></tr>"
"<tr><td>SSID ")) +
String(softAP_ssid) +
F("</td></tr>"
"<tr><td>IP ") +
toStringIp(WiFi.softAPIP()) +
F("</td></tr>"
"</table>"
"\r\n<br />"
"<table><tr><th align='left'>WLAN config</th></tr>"
"<tr><td>SSID ") +
String(ssid) +
F("</td></tr>"
"<tr><td>IP ") +
toStringIp(WiFi.localIP()) +
F("</td></tr>"
"</table>"
"\r\n<br />"
"<table><tr><th align='left'>WLAN list (refresh if any missing)</th></tr>");
Serial.println("scan start");
int n = WiFi.scanNetworks();
Serial.println("scan done");
if (n > 0) {
for (int i = 0; i < n; i++) {
Page += String(F("\r\n<tr><td>SSID ")) + WiFi.SSID(i) + ((WiFi.encryptionType(i) == ENC_TYPE_NONE) ? F(" ") : F(" *")) + F(" (") + WiFi.RSSI(i) + F(")</td></tr>");
}
} else {
Page += F("<tr><td>No WLAN found</td></tr>");
}
Page += F(
"</table>"
"\r\n<br /><form method='POST' action='wifisave'><h4>Connect to network:</h4>"
"<input type='text' placeholder='network' name='n'/>"
"<br /><input type='password' placeholder='password' name='p'/>"
"<br /><input type='submit' value='Connect/Disconnect'/></form>"
"<p>You may want to <a href='/'>return to the home page</a>.</p>"
"</body></html>");
server.send(200, "text/html", Page);
server.client().stop(); // Stop is needed because we sent no content length
}
/** Handle the WLAN save form and redirect to WLAN config page again */
void handleWifiSave() {
Serial.println("wifi save");
server.arg("n").toCharArray(ssid, sizeof(ssid) - 1);
server.arg("p").toCharArray(password, sizeof(password) - 1);
server.sendHeader("Location", "wifi", true);
server.sendHeader("Cache-Control", "no-cache, no-store, must-revalidate");
server.sendHeader("Pragma", "no-cache");
server.sendHeader("Expires", "-1");
server.send(302, "text/plain", ""); // Empty content inhibits Content-length header so we have to close the socket ourselves.
server.client().stop(); // Stop is needed because we sent no content length
saveCredentials();
connect = strlen(ssid) > 0; // Request WLAN connect with new credentials if there is a SSID
}
void handleNotFound() {
if (captivePortal()) { // If caprive portal redirect instead of displaying the error page.
return;
}
String message = F("File Not Found\n\n");
message += F("URI: ");
message += server.uri();
message += F("\nMethod: ");
message += (server.method() == HTTP_GET) ? "GET" : "POST";
message += F("\nArguments: ");
message += server.args();
message += F("\n");
for (uint8_t i = 0; i < server.args(); i++) {
message += String(F(" ")) + server.argName(i) + F(": ") + server.arg(i) + F("\n");
}
server.sendHeader("Cache-Control", "no-cache, no-store, must-revalidate");
server.sendHeader("Pragma", "no-cache");
server.sendHeader("Expires", "-1");
server.send(404, "text/plain", message);
}
void setup() {
delay(1000);
Serial.begin(9600);
Serial.println();
Serial.println("Configuring access point...");
/* You can remove the password parameter if you want the AP to be open. */
WiFi.softAPConfig(apIP, apIP, netMsk);
WiFi.softAP(softAP_ssid, softAP_password);
delay(500); // Without delay I've seen the IP address blank
Serial.print("AP IP address: ");
Serial.println(WiFi.softAPIP());
/* Setup the DNS server redirecting all the domains to the apIP */
dnsServer.setErrorReplyCode(DNSReplyCode::NoError);
dnsServer.start(DNS_PORT, "*", apIP);
/* Setup web pages: root, wifi config pages, SO captive portal detectors and not found. */
server.on("/", handleRoot);
server.on("/wifi", handleWifi);
server.on("/wifisave", handleWifiSave);
server.on("/generate_204", handleRoot); //Android captive portal. Maybe not needed. Might be handled by notFound handler.
server.on("/fwlink", handleRoot); //Microsoft captive portal. Maybe not needed. Might be handled by notFound handler.
server.onNotFound(handleNotFound);
server.begin(); // Web server start
Serial.println("HTTP server started");
loadCredentials(); // Load WLAN credentials from network
connect = strlen(ssid) > 0; // Request WLAN connect if there is a SSID
}
void connectWifi() {
Serial.println("Connecting as wifi client...");
WiFi.disconnect();
WiFi.begin(ssid, password);
int connRes = WiFi.waitForConnectResult();
Serial.print("connRes: ");
Serial.println(connRes);
}
void loop() {
if (connect) {
Serial.println("Connect requested");
connect = false;
connectWifi();
lastConnectTry = millis();
}
{
unsigned int s = WiFi.status();
if (s == 0 && millis() > (lastConnectTry + 60000)) {
/* If WLAN disconnected and idle try to connect */
/* Don't set retry time too low as retry interfere the softAP operation */
connect = true;
}
if (status != s) { // WLAN status change
Serial.print("Status: ");
Serial.println(s);
status = s;
if (s == WL_CONNECTED) {
/* Just connected to WLAN */
Serial.println("");
Serial.print("Connected to ");
Serial.println(ssid);
Serial.print("IP address: ");
Serial.println(WiFi.localIP());
// Setup MDNS responder
if (!MDNS.begin(myHostname)) {
Serial.println("Error setting up MDNS responder!");
} else {
Serial.println("mDNS responder started");
// Add service to MDNS-SD
MDNS.addService("http", "tcp", 80);
}
} else if (s == WL_NO_SSID_AVAIL) {
WiFi.disconnect();
}
}
if (s == WL_CONNECTED) {
MDNS.update();
}
}
// Do work:
//DNS
dnsServer.processNextRequest();
//HTTP
server.handleClient();
}
找到这个：https://www.esp8266.com/viewtopic.php?f=6&t=15993
eduperez 的这个 post：
"Android devices have the Google DNSs hard-coded, they will always use 8.8.8.8 and 8.8.4.4, despite what the DHPC server might tell them to use. You need to configure your gateway to redirect all outgoing traffic to port 53 to your DNS."
这给出了想法，使用 8.8.8.8 作为 IP 地址和 DNS 服务器地址。 多田！很有魅力！
所以这个草图可以工作：
#include <ESP8266WiFi.h>
#include <WiFiClient.h>
#include <ESP8266WebServer.h>
#include <DNSServer.h>
#include <ESP8266mDNS.h>
#include <EEPROM.h>
/*
This example serves a "hello world" on a WLAN and a SoftAP at the same time.
The SoftAP allow you to configure WLAN parameters at run time. They are not setup in the sketch but saved on EEPROM.
Connect your computer or cell phone to wifi network ESP_ap with password 12345678. A popup may appear and it allow you to go to WLAN config. If it does not then navigate to http://192.168.4.1/wifi and config it there.
Then wait for the module to connect to your wifi and take note of the WLAN IP it got. Then you can disconnect from ESP_ap and return to your regular WLAN.
Now the ESP8266 is in your network. You can reach it through http://192.168.x.x/ (the IP you took note of) or maybe at http://esp8266.local too.
This is a captive portal because through the softAP it will redirect any http request to http://192.168.4.1/
*/
/* Set these to your desired softAP credentials. They are not configurable at runtime */
#ifndef APSSID
#define APSSID "TheGeekMan"
#define APPSK "12345678"
#endif
const char *softAP_ssid = APSSID;
const char *softAP_password = APPSK;
/* hostname for mDNS. Should work at least on windows. Try http://esp8266.local */
const char *myHostname = "thegeekman";
/* Don't set this wifi credentials. They are configurated at runtime and stored on EEPROM */
char ssid[32] = "";
char password[32] = "";
// DNS server
const byte DNS_PORT = 53;
DNSServer dnsServer;
// Web server
ESP8266WebServer server(80);
/* Soft AP network parameters */
//IPAddress apIP(192, 168, 4, 1);
IPAddress apIP(8, 8, 8, 8);
IPAddress netMsk(255, 255, 255, 0);
/** Should I connect to WLAN asap? */
boolean connect;
/** Last time I tried to connect to WLAN */
unsigned long lastConnectTry = 0;
/** Current WLAN status */
unsigned int status = WL_IDLE_STATUS;
/** Is this an IP? */
boolean isIp(String str) {
for (size_t i = 0; i < str.length(); i++) {
int c = str.charAt(i);
if (c != '.' && (c < '0' || c > '9')) {
return false;
}
}
return true;
}
/** IP to String? */
String toStringIp(IPAddress ip) {
String res = "";
for (int i = 0; i < 3; i++) {
res += String((ip >> (8 * i)) & 0xFF) + ".";
}
res += String(((ip >> 8 * 3)) & 0xFF);
return res;
}
/** Load WLAN credentials from EEPROM */
void loadCredentials() {
EEPROM.begin(512);
EEPROM.get(0, ssid);
EEPROM.get(0 + sizeof(ssid), password);
char ok[2 + 1];
EEPROM.get(0 + sizeof(ssid) + sizeof(password), ok);
EEPROM.end();
if (String(ok) != String("OK")) {
ssid[0] = 0;
password[0] = 0;
}
Serial.println("Recovered credentials:");
Serial.println(ssid);
Serial.println(strlen(password) > 0 ? "********" : "<no password>");
}
/** Store WLAN credentials to EEPROM */
void saveCredentials() {
EEPROM.begin(512);
EEPROM.put(0, ssid);
EEPROM.put(0 + sizeof(ssid), password);
char ok[2 + 1] = "OK";
EEPROM.put(0 + sizeof(ssid) + sizeof(password), ok);
EEPROM.commit();
EEPROM.end();
}
/** Handle root or redirect to captive portal */
void handleRoot() {
if (captivePortal()) { // If caprive portal redirect instead of displaying the page.
return;
}
server.sendHeader("Cache-Control", "no-cache, no-store, must-revalidate");
server.sendHeader("Pragma", "no-cache");
server.sendHeader("Expires", "-1");
String Page;
Page += F(
"<html><head></head><body>"
"<h1>HELLO WORLD!!</h1>");
if (server.client().localIP() == apIP) {
Page += String(F("<p>You are connected through the soft AP: ")) + softAP_ssid + F("</p>");
} else {
Page += String(F("<p>You are connected through the wifi network: ")) + ssid + F("</p>");
}
Page += F(
"<p>You may want to <a href='/wifi'>config the wifi connection</a>.</p>"
"</body></html>");
server.send(200, "text/html", Page);
}
/** Redirect to captive portal if we got a request for another domain. Return true in that case so the page handler do not try to handle the request again. */
boolean captivePortal() {
if (!isIp(server.hostHeader()) && server.hostHeader() != (String(myHostname) + ".local")) {
Serial.println("Request redirected to captive portal");
server.sendHeader("Location", String("http://") + toStringIp(server.client().localIP()), true);
server.send(302, "text/plain", ""); // Empty content inhibits Content-length header so we have to close the socket ourselves.
server.client().stop(); // Stop is needed because we sent no content length
return true;
}
return false;
}
/** Wifi config page handler */
void handleWifi() {
server.sendHeader("Cache-Control", "no-cache, no-store, must-revalidate");
server.sendHeader("Pragma", "no-cache");
server.sendHeader("Expires", "-1");
String Page;
Page += F(
"<html><head></head><body>"
"<h1>Wifi config</h1>");
if (server.client().localIP() == apIP) {
Page += String(F("<p>You are connected through the soft AP: ")) + softAP_ssid + F("</p>");
} else {
Page += String(F("<p>You are connected through the wifi network: ")) + ssid + F("</p>");
}
Page +=
String(F(
"\r\n<br />"
"<table><tr><th align='left'>SoftAP config</th></tr>"
"<tr><td>SSID ")) +
String(softAP_ssid) +
F("</td></tr>"
"<tr><td>IP ") +
toStringIp(WiFi.softAPIP()) +
F("</td></tr>"
"</table>"
"\r\n<br />"
"<table><tr><th align='left'>WLAN config</th></tr>"
"<tr><td>SSID ") +
String(ssid) +
F("</td></tr>"
"<tr><td>IP ") +
toStringIp(WiFi.localIP()) +
F("</td></tr>"
"</table>"
"\r\n<br />"
"<table><tr><th align='left'>WLAN list (refresh if any missing)</th></tr>");
Serial.println("scan start");
int n = WiFi.scanNetworks();
Serial.println("scan done");
if (n > 0) {
for (int i = 0; i < n; i++) {
Page += String(F("\r\n<tr><td>SSID ")) + WiFi.SSID(i) + ((WiFi.encryptionType(i) == ENC_TYPE_NONE) ? F(" ") : F(" *")) + F(" (") + WiFi.RSSI(i) + F(")</td></tr>");
}
} else {
Page += F("<tr><td>No WLAN found</td></tr>");
}
Page += F(
"</table>"
"\r\n<br /><form method='POST' action='wifisave'><h4>Connect to network:</h4>"
"<input type='text' placeholder='network' name='n'/>"
"<br /><input type='password' placeholder='password' name='p'/>"
"<br /><input type='submit' value='Connect/Disconnect'/></form>"
"<p>You may want to <a href='/'>return to the home page</a>.</p>"
"</body></html>");
server.send(200, "text/html", Page);
server.client().stop(); // Stop is needed because we sent no content length
}
/** Handle the WLAN save form and redirect to WLAN config page again */
void handleWifiSave() {
Serial.println("wifi save");
server.arg("n").toCharArray(ssid, sizeof(ssid) - 1);
server.arg("p").toCharArray(password, sizeof(password) - 1);
server.sendHeader("Location", "wifi", true);
server.sendHeader("Cache-Control", "no-cache, no-store, must-revalidate");
server.sendHeader("Pragma", "no-cache");
server.sendHeader("Expires", "-1");
server.send(302, "text/plain", ""); // Empty content inhibits Content-length header so we have to close the socket ourselves.
server.client().stop(); // Stop is needed because we sent no content length
saveCredentials();
connect = strlen(ssid) > 0; // Request WLAN connect with new credentials if there is a SSID
}
void handleNotFound() {
if (captivePortal()) { // If caprive portal redirect instead of displaying the error page.
return;
}
String message = F("File Not Found\n\n");
message += F("URI: ");
message += server.uri();
message += F("\nMethod: ");
message += (server.method() == HTTP_GET) ? "GET" : "POST";
message += F("\nArguments: ");
message += server.args();
message += F("\n");
for (uint8_t i = 0; i < server.args(); i++) {
message += String(F(" ")) + server.argName(i) + F(": ") + server.arg(i) + F("\n");
}
server.sendHeader("Cache-Control", "no-cache, no-store, must-revalidate");
server.sendHeader("Pragma", "no-cache");
server.sendHeader("Expires", "-1");
server.send(404, "text/plain", message);
}
void setup() {
delay(1000);
Serial.begin(9600);
Serial.println();
Serial.println("Configuring access point...");
/* You can remove the password parameter if you want the AP to be open. */
WiFi.softAPConfig(apIP, apIP, netMsk);
WiFi.softAP(softAP_ssid, softAP_password);
delay(500); // Without delay I've seen the IP address blank
Serial.print("AP IP address: ");
Serial.println(WiFi.softAPIP());
/* Setup the DNS server redirecting all the domains to the apIP */
dnsServer.setErrorReplyCode(DNSReplyCode::NoError);
dnsServer.start(DNS_PORT, "*", apIP);
/* Setup web pages: root, wifi config pages, SO captive portal detectors and not found. */
server.on("/", handleRoot);
server.on("/wifi", handleWifi);
server.on("/wifisave", handleWifiSave);
server.on("/generate_204", handleRoot); //Android captive portal. Maybe not needed. Might be handled by notFound handler.
server.on("/fwlink", handleRoot); //Microsoft captive portal. Maybe not needed. Might be handled by notFound handler.
server.onNotFound(handleNotFound);
server.begin(); // Web server start
Serial.println("HTTP server started");
loadCredentials(); // Load WLAN credentials from network
connect = strlen(ssid) > 0; // Request WLAN connect if there is a SSID
}
void connectWifi() {
Serial.println("Connecting as wifi client...");
WiFi.disconnect();
WiFi.begin(ssid, password);
int connRes = WiFi.waitForConnectResult();
Serial.print("connRes: ");
Serial.println(connRes);
}
void loop() {
if (connect) {
Serial.println("Connect requested");
connect = false;
connectWifi();
lastConnectTry = millis();
}
{
unsigned int s = WiFi.status();
if (s == 0 && millis() > (lastConnectTry + 60000)) {
/* If WLAN disconnected and idle try to connect */
/* Don't set retry time too low as retry interfere the softAP operation */
connect = true;
}
if (status != s) { // WLAN status change
Serial.print("Status: ");
Serial.println(s);
status = s;
if (s == WL_CONNECTED) {
/* Just connected to WLAN */
Serial.println("");
Serial.print("Connected to ");
Serial.println(ssid);
Serial.print("IP address: ");
Serial.println(WiFi.localIP());
// Setup MDNS responder
if (!MDNS.begin(myHostname)) {
Serial.println("Error setting up MDNS responder!");
} else {
Serial.println("mDNS responder started");
// Add service to MDNS-SD
MDNS.addService("http", "tcp", 80);
}
} else if (s == WL_NO_SSID_AVAIL) {
WiFi.disconnect();
}
}
if (s == WL_CONNECTED) {
MDNS.update();
}
}
// Do work:
//DNS
dnsServer.processNextRequest();
//HTTP
server.handleClient();
}
关键不仅要使用8.8.8.8作为DNS地址，还要为NotFound的情况添加处理程序。我知道它包含在问题代码中，但我发现它对于 android auto-detect 强制门户
是强制性的在提供 HTTP 服务器时，您通常有两种选择：
- 使用 WebServer class 并设置根处理程序。 HTTP header 的解析和处理由库完成。
- 使用 WifiServer 并接收包含 header 的 HTTP 消息，并自行处理所有内容。
如果您正在做第 1 件事并假装通过连接 Android 设备使用，我建议为显示强制门户的错误情况添加一个处理程序：
server.onNotFound(handleRoot);
我注意到对于 Android 10，要正确检测强制门户并使 phone 显示“触摸以登录网络”消息是必要的。如果不是，您必须导航到任何 HTTP 地址并让 DNS 为您完成工作（不是 HTTPS）。
编辑：事实上，不使用 8.8.8.8 或 8.8.4.4（即使用 192.168.0.1）它对我有用。但我必须包含错误的处理程序 (onNotFound)