acme_vault

Table of Contents

  1. Description
  2. Setup - The basics of getting started with acme_vault
  3. Usage - Configuration options and additional functionality
  4. Reference - An under-the-hood peek at what the module is doing and how
  5. Limitations - OS compatibility, etc.
  6. Development - Guide for contributing to the module

Description

This module uses acme.sh to request letsencrypt certificates using the DNS-01 challenge. Once valid certificates are recieved, they are stored in Hashicorp vault where they can be retrieved by any appropriate machine.

This module consists of a common class, a request class, and a deploy class. The request class is intended to be enabled on a single machine that will handle all the certificate request and validation. The deploy class is then enabled on any machine that requires the requested certificates.

Setup

What acme_vault affects

This module will create a new system user that is used to request and deploy certificates.

This module also assumes a working installation of vault.

Beginning with acme_vault

Just include the appropriate modules for the appropriate machines, and make sure the required values are provided via hiera or class. Note: the common module must be included before either.

Typically this would involve a profile like:

class profiles::acme_request {

  include ::acme_vault::common
  include ::acme_vault::request

}

Usage

This section is where you describe how to customize, configure, and do the fancy stuff with your module here. It's especially helpful if you include usage examples and code samples for doing things with your module.

Reference

Classes:

Classes

acme_vault::common

This class needs to be included before acme_vault::request or acme_vault::deploy and contains configurations common to both. The user, vault, vault vars, and cron mailto are needed for both request and deploy

user

user to be created to request/deploy certs

Default value: acme_vault

group

group that owns the created certificates

group_members

members of the above group that will have access to created certificates. In most cases this will be the webserver group, or any other services that require reading the certs.

Default value: acme_vault

home_dir

home dir of the above user, where scripts and config will be stored.

Default value: /home/$user

contact_email

contact email used for cert registration, also used as MAILTO variable for cron jobs

Default value: ''

domains

mapping of domains to be included in the cert. The key is the "main" domain, and the value is the list of extra names to be requested. Both the main domain and the list of domains are included.

REQUIRED

vault_token

Vault token for authenticating to vault. This should have appropriate permissions applied in vault. A demo script is provided here

REQUIRED

vault_addr

Address of vault server

REQUIRED

vault_bin

Path to the vault binary.

Default value: /usr/local/bin/vault"

vault_prefix

The path within vault where the certificates will be stored and retrieved.

Default value: /secret/letsencrypt/

acme_vault::request

This class uses acme.sh, and pulls down the git repo for it. It uses the namecheap provider in acme.sh to do the dns updating for the dns-01 challenge. It configures a cron job to periodically check if a cert needs renewal.

Note: it does not automatically trigger requesting certs, but relies on cron coordination to eventually reach the desired end state. Since certificate renewal has a large time window, this is acceptable. Any urgent issue/renewals can be triggered by running the cron job manually as needed.

Parameters inherited from common, but can be overriden:

user

user to be created to request/deploy certs

Default value: acme_vault

group

group that the user belongs to. For deploy, this should probably be the webserver group

Default value: acme_vault

home_dir

home dir of the above user, where scripts and config will be stored.

Default value: /home/$user

contact_email

contact email used for cert registration, also used as MAILTO variable for cron jobs

Default value: ''

domains

mapping of domains to be included in the cert. The key is the "main" domain, and the value is the list of extra names to be requested. Both the main domain and the list of domains are included.

REQUIRED

Parameters only for request:

staging

whether to use the acme staging endpoint

Valid values: true, false

Default value: false

staging_url

url to acme staging endpoint

Default value: https://acme-staging-v02.api.letsencrypt.org/directory

prod_url

url to the acme prod endpoint

Default value: https://acme-v02.api.letsencrypt.org/directory

acme_revision

git revision/tag to be used to checkout acme.sh repository.

Default value: HEAD

acme_repo_path

where the repo should be checked out.

Default value: $home_dir/acme.sh

acme_script

path the the acme.sh script itself

Default value: $acme_repo_path/acme.sh

namecheap_sourceip

sourceip for namecheap requests (it is well known that this is ignored by their api)

Default value: 127.0.0.1

REQUIRED

namecheap_username

username for namecheap dns api.

REQUIRED

namecheap_api_key

token for namecheap api user.

REQUIRED

acme_vault::deploy

This class handles taking a cert/key out of vault, and placing it in a configured path on the filesystem. It will also accept a restart command to restart any appropriate services to take advantage of the new cert.

It employs a script, check_cert.sh, to validate the cert in vault exists, and is appropriate to replace the existing one

Parameters inherited from common, but can be overriden:

user

user to be created to request/deploy certs

Default value: acme_vault

group

group that the user belongs to. For deploy, this should probably be the webserver group

Default value: acme_vault

home_dir

home dir of the above user, where scripts and config will be stored.

Default value: /home/$user

domains

mapping of domains to be included in the cert. The key is the "main" domain, and the value is the list of extra names to be requested. Both the main domain and the list of domains are included.

REQUIRED

Parameters only for deploy:

cert_destination_path

where the cert should be deployed to. cert will end up in $cert_destination_path/$domain/.

Default value: /etc/acme

deploy_scripts

location for arbitrary scripts to reload certificates for applications. scripts will end up in $cert_destination_path/deploy.d/

Default value: /etc/acme/deploy.d

restart_method

shell that is run after successful deployment. runs scripts in $deploy_scripts

Default value: for f in /etc/acme/deploy.d/*.sh; do "$f"; done

Limitations

Has only been tested on Centos 7

Development

Contributions are welcome!