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@MaBecker
Created August 18, 2017 08:24
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// Captive Portal
var http = require('http');
var Wifi = require('Wifi');
var dgram = require('dgram');
var server = dgram.createSocket('udp4');
var SSID = 'CaptivePortalTest';
var authMode = 'open';
var password = null;
var portHTTP = 80;
var portDNS = 53;
var dnsIPStr = '192.168.4.1';
var dnsIP = dnsIPStr.split('.').map(n => String.fromCharCode(parseInt(n, 10))).join('');
var page = '<html><body><H1>Hello World</H1></body></html>';
// get Query name out of message
// offset = 12
// end \x00
function dnsQname(msg) {
var i = 12;
var qname = '';
while ( msg[i] !== '\x00' ) {
qname += msg[i];
i++;
}
return qname + '\x00';
}
/*
1. line header
2. line query
3. line resource
*/
function dnsResponse(msg,dns_ip){
return msg[0]+msg[1] + '\x81\x80'+'\x00\x01'+'\x00\x01'+'\x00\x00\x00\x00' +
dnsQname(msg) + '\x00\x01' + '\x00\x01' +
'\xc0\x0c'+'\x00\x01'+'\x00\x01'+'\x00\x00\x00\xf9'+'\x00\x04' + dns_ip ;
}
function startDNSServer(port){
server.on('error', (err) => {
server.close();
});
server.on('message', (msg, info) => {
// we only serve ip4
if ( msg[msg.length-3] === '\x01') {
server.send(dnsResponse(msg,dnsIP),info.port,info.address);
}
});
server.bind(port);
}
// start http server
function startHttpServer(port){
var server = http.createServer(function (req, res) {
accept = req.headers.Accept || '';
if (accept !== '*\/*') {
res.writeHead(200, {'Content-Type': 'text/html'});
res.end(page);
} else { // redirect to the Setup page
res.writeHead(302, {'Location': 'http://192.168.4.1',
'Content-Type': 'text/plain'});
res.end();
}
});
server.listen(port);
}
// start beeing a access point
function startAccessPoint(ssid,authMode, password){
Wifi.startAP(ssid,{"authMode" : authMode,"password" : password});
}
// stop beeing connected to a access point
function disconnectStation(){
Wifi.disconnect();
}
function start(){
disconnectStation();
startAccessPoint('CaptivePortalTest','open',null);
startHttpServer(80);
startDNSServer(53);
}
setTimeout(start,1000);
@tombueng
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