express-ipfilter: A light-weight IP address based filtering system

This package provides easy IP based access control. This can be achieved either by blacklisting certain IPs and whitelisting all others, or whitelisting certain IPs and blacklisting all others.

Installation

Recommended installation is with npm. To add express-ipfilter to your project, do:

npm install varmil/express-ipfilter

Usage with Express

Blacklisting certain IP addresses, while allowing all other IPs:

1// Init dependencies
2const express = require('express')
3const ipfilter = require('express-ipfilter').IpFilter
4
5// Blacklist the following IPs
6const ips = ['127.0.0.1']
7
8// Create the server
9app.use(ipfilter(ips))
10app.listen(3000)

Whitelisting certain IP addresses, while denying all other IPs:

1// Init dependencies
2// Init dependencies
3const express = require('express')
4const ipfilter = require('express-ipfilter').IpFilter
5
6// Whitelist the following IPs
7const ips = ['127.0.0.1']
8
9// Create the server
10app.use(ipfilter(ips, { mode: 'allow' }))
11
12module.exports = app

Using CIDR subnet masks for ranges:

1const ips = ['127.0.0.1/24']
2
3// Create the server
4app.use(ipfilter(ips, { mode: 'allow' }))
5
6module.exports = app

Using IP ranges:

1const ips = [['127.0.0.1', '127.0.0.10']]
2
3// Create the server
4app.use(ipfilter(ips, { mode: 'allow' }))
5
6module.exports = app

Using a function to get Ips:

1const ips = function(req) {
2  return ['127.0.0.1']
3}
4
5// Create the server
6app.use(ipfilter(ips, { mode: 'allow' }))
7
8module.exports = app

Error Handling

When an IP is denied, an IpDeniedError will be thrown by the middleware. If you do not handle the error, it will cause your app to crash due to an unhandled exception. Here is an example of how to handle the error, which can also be found in the example app:

1if (app.get('env') === 'development') {
2  app.use((err, req, res, _next) => {
3    console.log('Error handler', err)
4    if (err instanceof IpDeniedError) {
5      res.status(401)
6    } else {
7      res.status(err.status || 500)
8    }
9
10    res.render('error', {
11      message: 'You shall not pass',
12      error: err
13    })
14  })
15}

You will need to require the IpDeniedError type in order to handle it.

Options

Property	Description	Type	Default
mode	whether to deny or allow to the IPs provided	string	deny
log	console log actions	boolean	true
logLevel	level of logging (all,deny,allow)	string	all
excluding	routes that should be excluded from ip filtering	array	[]
detectIp	define a custom function that takes an Express request object and returns an IP address to test against	function	built-in detection
trustProxy	This setting is implemented using the proxy-addr package. Check the documentation for the trust parameter.	boolean, array, string, number, function	false

A note on detectIp

If you need to parse an IP address in a way that is not supported by default, you can write your own parser and pass that to ipfilter.

1const customDetection = req => {
2  var ipAddress
3
4  ipAddress = req.connection.remoteAddress.replace(/\//g, '.')
5
6  return ipAddress
7}
8
9ipfilter(ids, { detectIp: customDetection })

Contributing

See the CONTRIBUTING.MD document for more information on contributing.

Running Tests

Run tests by using npm test

Changelog

Moved to GitHub Releases

Credits

BaM Interactive - code.bamideas.com