dns-suite.js/node_modules/native-dns-cache/lookup.js

111 lines
3.1 KiB
JavaScript
Raw Normal View History

2017-01-14 02:04:27 +00:00
// Copyright 2012 Timothy J Fontaine <tjfontaine@gmail.com>
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE
var dgram = require('dgram'),
EventEmitter = require('events').EventEmitter,
net = require('net'),
util = require('util');
var is_absolute = exports.is_absolute = function (f) {
return f && /\.$/.test(f);
};
var ensure_absolute = exports.ensure_absolute = function (f) {
if (!is_absolute(f))
return f += '.';
return f;
};
var CNAME = require('native-dns-packet').consts.NAME_TO_QTYPE.CNAME;
var Lookup = exports.Lookup = function (store, zone, question, cb) {
if (!(this instanceof Lookup))
return new Lookup(store, zone, question, cb);
this.store = store;
this.zone = zone;
this.cb = cb;
this.question = question;
this.results = [];
this.wildcard = undefined;
this.name = ensure_absolute(question.name);
this.store.get(this.zone, this.name, this.lookup.bind(this));
};
Lookup.prototype.send = function (err) {
this.cb(err, this.results);
};
Lookup.prototype.lookup = function (err, results) {
var type, ret, name, self = this;
if (err)
return this.send(err);
if (!results) {
if (!this.wildcard)
this.wildcard = this.question.name;
if (this.wildcard.toLowerCase() == this.zone.toLowerCase())
return this.send();
name = this.wildcard = this.wildcard.split('.').splice(1).join('.');
// 'com.'.split('.').splice(1) will return empty string, we're at the end
if (!this.wildcard)
return this.send();
name = '*.' + name;
} else if (results[this.question.type]) {
type = this.question.type;
ret = results;
} else if (results[CNAME]) {
type = CNAME;
ret = results;
this.name = name = results[CNAME][0].data
}
if (ret) {
ret = ret[type];
ret.forEach(function (r) {
var rr, k;
if (self.wildcard && /^\*/.test(r.name)) {
rr = {};
for (k in r) {
rr[k] = r[k];
}
rr.name = self.name;
} else {
rr = r;
}
self.results.push(rr);
});
}
if (name)
this.store.get(this.zone, ensure_absolute(name), this.lookup.bind(this));
else
this.send();
};