dylannlaw / cert-info.js

cert-info.js

Read basic info from a cert.pem / x509 certificate.

Used for Greenlock.js

Features

| <175 lines of code | 1.7k gzipped | 4.4k minified | 8.8k with comments |

• Parses x.509 certificate schemas
  • DER/ASN.1
  • PEM (base64-encoded DER)
  • Subject
  • SAN extension (altNames)
  • Issuance Date (notBefore)
  • Expiry Date (notAfter)
• VanillaJS, Zero Dependencies
  • Node.js
  • Browsers (built, publishing soon)

Install

# bin
npm install --global cert-info

# node.js library
npm install --save cert-info

Usage

CLI

For basic info (subject, altnames, issuedAt, expiresAt):

cert-info /path/to/cert.pem

node.js

'use strict';

var certinfo = require('cert-info');
var cert = fs.readFile('cert.pem', 'ascii', function (err, certstr) {

  // basic info
  console.info(certinfo.info(certstr));

  // if you need to submit a bug report
  console.info(certinfo.debug(certstr));
});

Example output:

{
  "subject": "localhost.example.com",
  "altnames": [
    "localhost.example.com"
  ],
  "issuedAt": 1465516800000,
  "expiresAt": 1499731199000
}

With a few small changes this could also work in the browser (it has no dependencies and all of the non-browser things are on the Enc object).

Legal

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