DNSJack
A simple DNS proxy that lets you intercept domains and route them to whatever IP you decide.
It's available through npm:
npm install dnsjack
It's easy to use:
var jack = require('dnsjack').createServer();
jack.route('www.google.com', '127.0.0.1'); // route all requests to www.google.com to localhost
jack.listen(); // it listens on the standard DNS port of 53 per default
// route all domains to 127.0.0.1
jack.route(function(data, callback) {
callback(null, '127.0.0.1');
});
// route all google domains to 127.0.0.1
jack.route(['google.com', '*.google.com'], function(data, callback) {
callback(null, '127.0.0.1');
});
// now all requests to google.com should be routed localhost
require('http').createServer(function(req, res) {
res.writeHead(200);
res.end('jack says hi!');
}).listen(80);
You probably need to run the above example with sudo
as we need to listen to port 80
and 53
.
Now change your local DNS server to 127.0.0.1
and visit http://www.google.com
in your browser.
DNSJack will forward all request that you don't route yourself to Google's DNS server or whatever DNS
you provide in .createServer()
.
You can also use it to monitor your DNS resolutions which can be super useful for debugging:
var jack = require('dnsjack').createServer();
jack.on('resolve', function(data) {
console.log(data.rinfo.address, 'is resolving', data.domain);
});
jack.listen();
You can also pass along the TTL when responding to a DNS request:
jack.route(['google.com', '*.google.com'], function(data, callback) {
callback(null, {ip: '127.0.0.1', ttl: 3600});
});