ACME cookbook

Automatically get/renew free and trusted certificates from Let's Encrypt (letsencrypt.org). ACME is the Automated Certificate Management Environment protocol used by Let's Encrypt.

Starting with v4.0.0 of the acme cookbook the acme_ssl_certificate provider has been removed! The TLS-SNI-01 validation method used by this provider been disabled by Let's Encrypt due to security concerns. Please switch to the acme_certificate provider in this cookbook to request and renew your certificate using the supported HTTP-01 validation method.

Attributes

Recipes

default

Installs the required acme-client rubygem.

Usage

Use the acme_certificate resource to request a certificate with the http-01 challenge. The webserver for the domain for which you are requesting a certificate must be running on the local server. This resource only supports the http validation method. To use the tls-sni-01 challenge, please see the resource below. Provide the path to your wwwroot for the specified domain.

acme_certificate 'test.example.com' do
  crt               '/etc/ssl/test.example.com.crt'
  key               '/etc/ssl/test.example.com.key'
  wwwroot           '/var/www'
end

If your webserver needs an existing certificate already when installing a new server, you will have a bootstrap problem: The web server cannot start without a certificate, but the certificate cannot be requested without the running web server. To overcome this, a temporary self-signed certificate can be generated with the acme_selfsigned resource, allowing the web server to start.

acme_selfsigned 'test.example.com' do
  crt     '/etc/ssl/test.example.com.crt'
  chain   '/etc/ssl/test.example.com-chain.crt'
  key     '/etc/ssl/test.example.com.key'
end

A working example can be found in the included acme_client test cookbook.

Providers

certificate

selfsigned

Example

To generate a certificate for an apache2 website you can use code like this:

# Include the recipe to install the gems
include_recipe 'acme'

# Set up contact information. Note the mailto: notation
node.override['acme']['contact'] = ['mailto:[email protected]']
# Real certificates please...
node.override['acme']['endpoint'] = 'https://acme-v01.api.letsencrypt.org'

site = "example.com"
sans = ["www.#{site}"]

# Generate a self-signed if we don't have a cert to prevent bootstrap problems
acme_selfsigned "#{site}" do
  crt     "/etc/httpd/ssl/#{site}.crt"
  key     "/etc/httpd/ssl/#{site}.key"
  chain    "/etc/httpd/ssl/#{site}.pem"
  owner   "apache"
  group   "apache"
  notifies :restart, "service[apache2]", :immediate
end

# Set up your web server here...

# Get and auto-renew the certificate from Let's Encrypt
acme_certificate "#{site}" do
  crt               "/etc/httpd/ssl/#{site}.crt"
  key               "/etc/httpd/ssl/#{site}.key"
  wwwroot           "/var/www/#{site}/htdocs/"
  notifies :restart, "service[apache2]"
  alt_names sans
end

Testing

The kitchen includes a pebble server to run the integration tests with, so testing can run locally without interaction with the online APIs.

Contributing

1. Fork the repository on Github
2. Create a named feature branch (like add_component_x)
3. Write your change
4. Write tests for your change (if applicable)
5. Run the tests, ensuring they all pass
6. Submit a Pull Request using Github

License and Authors

Authors: Thijs Houtenbos [email protected]

Credits

Let’s Encrypt is a trademark of the Internet Security Research Group. All rights reserved.