pem

What is pem?

The 'pem' npm package is a tool for creating and managing PEM (Privacy Enhanced Mail) files, which are commonly used for SSL/TLS certificates and keys. It provides a variety of functionalities for generating, reading, and managing these files.

What are pem's main functionalities?

Generate SSL Certificates

This feature allows you to generate self-signed SSL certificates. The code sample demonstrates how to create a certificate that is valid for one day.

const pem = require('pem');
pem.createCertificate({ days: 1, selfSigned: true }, function (err, keys) {
  if (err) {
    throw err;
  }
  console.log(keys);
});

Read Certificate Information

This feature allows you to read and extract information from an existing certificate. The code sample shows how to read certificate information from a specified file path.

const pem = require('pem');
pem.readCertificateInfo('path/to/certificate.pem', function (err, info) {
  if (err) {
    throw err;
  }
  console.log(info);
});

Create Certificate Signing Request (CSR)

This feature allows you to create a Certificate Signing Request (CSR), which is used to request a certificate from a Certificate Authority (CA). The code sample demonstrates how to create a CSR with a specified common name.

const pem = require('pem');
pem.createCSR({ commonName: 'example.com' }, function (err, csr) {
  if (err) {
    throw err;
  }
  console.log(csr);
});

Create Private Key

This feature allows you to generate a private key. The code sample shows how to create a private key using the 'pem' package.

const pem = require('pem');
pem.createPrivateKey(function (err, key) {
  if (err) {
    throw err;
  }
  console.log(key);
});

Other packages similar to pem

node-forge

The 'node-forge' package is a comprehensive library for implementing various cryptographic functionalities in Node.js. It includes features for working with SSL/TLS, X.509 certificates, and more. Compared to 'pem', 'node-forge' offers a broader range of cryptographic tools but may require more in-depth knowledge to use effectively.

openssl-wrapper

The 'openssl-wrapper' package is a Node.js wrapper for the OpenSSL command-line tool. It allows you to perform various cryptographic operations using OpenSSL commands. While 'openssl-wrapper' provides a wide range of functionalities similar to 'pem', it relies on having OpenSSL installed on the system and may be less user-friendly for those unfamiliar with OpenSSL commands.

pkijs

The 'pkijs' package is a JavaScript library for Public Key Infrastructure (PKI) and X.509 certificates. It provides tools for creating, parsing, and validating certificates. Compared to 'pem', 'pkijs' is more focused on PKI and X.509 standards and offers more advanced features for working with certificates.

README

pem

Create private keys and certificates with node.js

Installation

Install with npm

npm install pem

or use yarn

yarn add pem

:warning: Please make sure you have openssl or libressl already installed on your system/container, without them pem will not work.

Examples

Here are some examples for creating an SSL key/cert on the fly, and running an HTTPS server on port 443. 443 is the standard HTTPS port, but requires root permissions on most systems. To get around this, you could use a higher port number, like 4300, and use https://localhost:4300 to access your server.

Basic https

var https = require('https')
var pem = require('pem')

pem.createCertificate({ days: 1, selfSigned: true }, function (err, keys) {
  if (err) {
    throw err
  }
  https.createServer({ key: keys.clientKey, cert: keys.certificate }, function (req, res) {
    res.end('o hai!')
  }).listen(443)
})

Express

var https = require('https')
var pem = require('pem')
var express = require('express')

pem.createCertificate({ days: 1, selfSigned: true }, function (err, keys) {
  if (err) {
    throw err
  }
  var app = express()

  app.get('/', function (req, res) {
    res.send('o hai!')
  })

  https.createServer({ key: keys.clientKey, cert: keys.certificate }, app).listen(443)
})

API

Please have a look into the API documentation.

we had to clean up a bit

Custom extensions config file

You can specify custom OpenSSL extensions using the config or extFile options for createCertificate (or using csrConfigFile with createCSR).

extFile and csrConfigFile should be paths to the extension files. While config will generate a temporary file from the supplied file contents.

If you specify config then the v3_req section of your config file will be used.

The following would be an example of a Certificate Authority extensions file:

[req]
req_extensions = v3_req
distinguished_name = req_distinguished_name

[req_distinguished_name]
commonName = Common Name
commonName_max = 64

[v3_req]
basicConstraints = critical,CA:TRUE

While the following would specify subjectAltNames in the resulting certificate:

[req]
req_extensions = v3_req

[ v3_req ]
basicConstraints = CA:FALSE
keyUsage = nonRepudiation, digitalSignature, keyEncipherment
subjectAltName = @alt_names

[alt_names]
DNS.1 = host1.example.com
DNS.2 = host2.example.com
DNS.3 = host3.example.com

Note that createCertificate and createCSR supports the altNames option which would be easier to use in most cases.

:warning: Warning: If you specify altNames the custom extensions file will not be passed to OpenSSL.

Setting openssl location

In some systems the openssl executable might not be available by the default name or it is not included in $PATH. In this case you can define the location of the executable yourself as a one time action after you have loaded the pem module:

var pem = require('pem')
pem.config({
  pathOpenSSL: '/usr/local/bin/openssl'
})
// do something with the pem module

:warning: CSR/Certificates with special chars

For more details, search in test/pem.spec.js: Create CSR with specialchars config file

If you use special chars like:

-!$%^&*()_+|~=`{}[]:/;<>?,.@#

You should know that the result mey have escaped characters when you read it in your application. Will try to fix this in the future, but not sure.

Special thanks to

• Andris Reinman (@andris9) - Initiator of pem

License

MIT