dnsbl

Query DNS-based blackhole lists

Support both IPv4 and IPv6 queries.

Installation

$ npm i dnsbl

Usage

import {lookup, batch} from 'dnsbl';

await lookup('127.0.0.2', 'zen.spamhaus.org');
// true

await lookup('127.0.0.2', 'zen.spamhaus.org', {includeTxt: true});
// {
//   listed: true,
//   txt: [['some txt'], ['another txt']]
// }

await batch(['1.2.3.4', '5.6.7.8'], ['dnsbl.somelist.net', 'dnsbl.someotherlist.net']);
// [
//   { blacklist: 'dnsbl.somelist.net', address: '1.2.3.4', listed: true },
//   { blacklist: 'dnsbl.somelist.net', address: '5.6.7.8', listed: false },
//   { blacklist: 'dnsbl.someotherlist.net', address: '1.2.3.4', listed: true },
//   { blacklist: 'dnsbl.someotherlist.net', address: '5.6.7.8', listed: false }
// ]

API

lookup(address, blacklist, [options])

• address: string an IP address.
• blacklist: string the hostname of the blacklist to query.

Returns a Promise that resolves to true or false, indicating if the address is listed (e.g. the DNS query returned a non-empty result). Will reject on error.

If the includeTxt option is set, it will return an Object with these properties:

• listed boolean - a boolean indicating if the address is listed on the blacklist.
• txt string[] - an array of resolved TXT records for the address.

batch(addresses, blacklists, [options])

• addresses string or Array - one or more IP addresses.
• blacklists string or Array - one or more blacklist hostnames.

Returns a Promise that resolve to a results object (see below).

options object

• servers string or Array - DNS servers to use. Pass a falsy value to use the system resolvers. Default: ['208.67.220.220', '208.67.222.222', '2620:119:35::35', '2620:119:53::53'].
• timeout number - timout in milliseconds. Default: 5000.
• concurrency number - number of concurrent queries. Default: 64.
• includeTxt boolean - include txt records if IP is blacklisted. Default: false.

results object

The results object is an array of objects with these properies:

• address string - the IP address.
• blacklist string - the blacklist hostname.
• listed boolean - a boolean indicating if the address is listed on the blacklist.
• txt string[] - an array of resolved TXT records for the address.

© silverwind, distributed under BSD licence