@shwao/express-fingerprint

Client fingerprint server implementation. Fork of https://github.com/yusukeshibata/express-fingerprint. Adds IP and DNT parameter.

Usage no npm install needed!

<script type="module">
  import shwaoExpressFingerprint from 'https://cdn.skypack.dev/@shwao/express-fingerprint';
</script>

README

Fingerprint express middleware

Information

This is a fork of https://github.com/yusukeshibata/express-fingerprint. I addition to adding a new parameters "IP" and "DNT", this package loads only the parameters you configured. Yusuke's version loaded all parameters as defaults and therefore loaded the geoip-lite database.

https://w3c.github.io/fingerprinting-guidance/#bib-NDSS-FINGERPRINTING

Passive fingerprinting is browser fingerprinting based on characteristics observable in the contents of Web requests, without the use of any code executing on the client side.

Passive fingerprinting would trivially include cookies (often unique identifiers sent in HTTP requests) and the set of HTTP request headers and the IP address and other network-level information. The User-Agent string, for example, is an HTTP request header that typically identifies the browser, renderer, version and operating system. For some populations, the user agent string and IP address will commonly uniquely identify a particular user's browser.

Default implementation is Never trust clients, So collect only server-side information. But you can push additional parameter with initialization config.

Installation

npm install @shwao/express-fingerprint

Usage

As a Express middleware

const Fingerprint = require('express-fingerprint');

app.use(Fingerprint([
        // Defaults
    Fingerprint.useragent(),
    Fingerprint.acceptHeaders(),
    Fingerprint.geoIp(),
    Fingerprint.ip(),
    Fingerprint.dnt(),

    // Additional parameters
    function(next) {
        // ...do something...
        next(null,{
        'param1':'value1'
        })
    },
    function(next) {
        // ...do something...
        next(null,{
        'param2':'value2'
        })
    },
]));

app.get('*',function(req,res,next) {
    // Fingerprint object
    console.log(req.fingerprint)
});

req.fingerprint object is like below.

{
    "hash": "bd767932c289b92b4de510f4c4d48246",
    "components": {
        "useragent": {
            "browser": {
                "family": "Chrome",
                "version": "50"
            },
            "device": {
                "family": "Other",
                "version": "0"
            },
            "os": {
                "family": "Mac OS",
                "major": "10",
                "minor":"11"
        },
        "acceptHeaders": {
            "accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8",
            "encoding": "gzip, deflate, sdch",
            "language": "en-US,en;q=0.8"
        },
        "geoip": {
            "country": "US",
            "resion": "CA",
            "city": "San Francisco"
        },
        "ip": "140.82.112.4",
        "dnt": true,
        "param1": "value1",
        "param2": "value2"
    }
}

List of fingerprinting sources

  • User Agent
  • HTTP_ACCEPT Headers
  • GEO-IP
  • IP
  • DNT

License

MIT