DNS lookup API

An API that allows a WebExtension to perform DNS lookups for arbitrary record types in a highly efficient manner.


Use DNS lookup to create a bridge between centralized and decentralized technologies.

There are two DNS resource record types that are relevant to this objective:

TXT records are much more versatile. There are historical examples of publishing PGP pubkeys, domain ownership verification, ‘serverless’ redirect services and more.

IPFS uses TXT records for publishing dnslink as a means of exposing content from an IPFS Path under /ipns/${fqdn}/ namespace. Validation of /ipns/ paths includes a DNS lookup to verify if /ipns/${fqdn} is backed by the presence of a dnslink TXT record.

Without a dedicated API for DNS lookups browser extensions are forced to use third-party DNS-over-HTTPS services. This workaround comes at a price:

Usage Documentation

The recently added browser.dns.resolve API from Firefox 60 is a good starting point. There should be an additional parameter that enables extension to lookup for record types different from the default A.

Example below shows how a lookup for TXT record could work in mentioned API:

function resolved(record) {

let resolving = browser.dns.resolve("ipfs.io", ["rr_type_txt"]);

// > e.g. Array [ "dnslink=/ipfs/QmYNQJoKGNHTpPxCBPh9KkDpaExgd2duMa3aF6ytMpHdao" ]