rdns.js

var dns = require("dns");
var net = require("net");
var fs = require("fs");
dns.setServers(["74.82.42.42", "208.67.222.222", "213.33.99.70"]);
var ip = "8.8.8";
if (process.argv.length == 3) {
  var _ip = process.argv[2];
  ip = _ip.split(".", 4).slice(0, 3).join(".");
}
rdns(ip, function(data) {
  if (data.length) {
    var logStream1 = fs.createWriteStream("dns1-" + (new Date).toISOString().split("T")[0] + ".txt", {"flags":"a"});
    logStream1.write(data.join("\n") + "\n");
    logStream1.close();
  }
});
function rdns(ip, callback) {
  var _i = 0, _j = 0, t1 = new Date;
  var arr = [];
  for (var i = 0;i < 255;i++) {
    _i++;
    process.nextTick(function(v) {
      var a = v.split(".").reverse().join(".") + ".in-addr.arpa";
      dns.resolvePtr(a, function(err, result) {
        _i--;
        if (err) {
        } else {
          console.log(v + "\t" + result.sort().join(", ").toLowerCase());
          arr.push(v + "\t" + result.sort().join(", ").toLowerCase());
          _j++;
        }
        if (_i == 0) {
          console.error("%s ms %s records, done.", new Date - t1, _j);
          if (callback) {
            callback(arr);
          }
        }
      });
    }, ip + "." + i);
  }
}
;