Revision control
Copy as Markdown
Other Tools
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
/**
* This module is responsible for performing DNS queries using ctypes for
* loading system DNS libraries on Linux, Mac and Windows.
*/
// These constants are luckily shared, but with different names
const NS_T_TXT = 16; // DNS_TYPE_TXT
const NS_T_SRV = 33; // DNS_TYPE_SRV
const NS_T_MX = 15; // DNS_TYPE_MX
export const DNS = {
/**
* Constants for use with the lookup function.
*/
TXT: NS_T_TXT,
SRV: NS_T_SRV,
MX: NS_T_MX,
worker: null,
/**
* Do an asynchronous DNS lookup. The returned promise resolves with
* one of SRVRecord, TXTRecord, or MXRecord objects as defined in
* dnsWorker.js, or rejects with the error from the worker.
*
* Example: await DNS.lookup("_caldavs._tcp.example.com", DNS.SRV)
*
* @param {string} _name - The hostname to look up records for.
* @param {string} _recordTypeID - The RR type to look up as a constant.
* @returns {Promise<object[]>} records
*/
async lookup(_name, _recordTypeID) {
// The platform-specific C APIs used for DNS lookup are not necessarily
// thread safe, so we maintain a single worker and allow requests to queue
// so they are executed serially.
if (!this.worker) {
);
const self = this;
// Ensure the worker is stopped prior to web worker shutdown.
AsyncShutdown.webWorkersShutdown.addBlocker(
"Thunderbird DNS: Shutting down.",
function () {
if (self.worker) {
self.worker.terminate();
// Allow GC.
self.worker = null;
}
}
);
}
return await this.worker.post("execute", [
AppConstants.platform,
AppConstants.unixstyle,
"lookup",
[...arguments],
]);
},
/**
* Look up SRV records for hostname.
*
* @param {string} hostname
* @returns {Promise<SRVRecord[]>} records.
*/
async srv(hostname) {
return this.lookup(hostname, NS_T_SRV);
},
/**
* Look up TXT records for hostname.
*
* @param {string} hostname
* @returns {Promise<TXTRecord[]>} records.
*/
async txt(hostname) {
return this.lookup(hostname, NS_T_TXT);
},
/**
* Look up MX records for hostname.
*
* @param {string} hostname
* @returns {Promise<MXRecord[]>} records.
*/
async mx(hostname) {
return this.lookup(hostname, NS_T_MX);
},
};