acme_certificate – Create SSL/TLS certificates with the ACME protocol

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Ansible/docs/2.7/modules/acme certificate module


acme_certificate – Create SSL/TLS certificates with the ACME protocol

New in version 2.2.


Synopsis

  • Create and renew SSL/TLS certificates with a CA supporting the ACME protocol, such as Let’s Encrypt. The current implementation supports the http-01, dns-01 and tls-alpn-01 challenges.
  • To use this module, it has to be executed twice. Either as two different tasks in the same run or during two runs. Note that the output of the first run needs to be recorded and passed to the second run as the module argument data.
  • Between these two tasks you have to fulfill the required steps for the chosen challenge by whatever means necessary. For http-01 that means creating the necessary challenge file on the destination webserver. For dns-01 the necessary dns record has to be created. For tls-alpn-01 the necessary certificate has to be created and served. It is not the responsibility of this module to perform these steps.
  • For details on how to fulfill these challenges, you might have to read through the main ACME specification and the TLS-ALPN-01 specification. Also, consider the examples provided for this module.

Aliases: letsencrypt

Requirements

The below requirements are needed on the host that executes this module.

  • python >= 2.6
  • either openssl, …
  • … or cryptography >= 1.5

Parameters

Parameter Choices/Defaults Comments

account_email

-

The email address associated with this account.

It will be used for certificate expiration warnings.

Note that when modify_account is not set to no and you also used the acme_account module to specify more than one contact for your account, this module will update your account and restrict it to the (at most one) contact email address specified here.

account_key_content

-

added in 2.5

Content of the ACME account RSA or Elliptic Curve key.

Mutually exclusive with account_key_src.

Required if account_key_src is not used.

Warning: the content will be written into a temporary file, which will be deleted by Ansible when the module completes. Since this is an important private key — it can be used to change the account key, or to revoke your certificates without knowing their private keys —, this might not be acceptable.

In case cryptography is used, the content is not written into a temporary file. It can still happen that it is written to disk by Ansible in the process of moving the module with its argument to the node where it is executed.

account_key_src

-

Path to a file containing the ACME account RSA or Elliptic Curve key.

RSA keys can be created with openssl genrsa .... Elliptic curve keys can be created with openssl ecparam -genkey .... Any other tool creating private keys in PEM format can be used as well.

Mutually exclusive with account_key_content.

Required if account_key_content is not used.


aliases: account_key

account_uri

-

added in 2.7

If specified, assumes that the account URI is as given. If the account key does not match this account, or an account with this URI does not exist, the module fails.

acme_directory

-

Default:

The ACME directory to use. This is the entry point URL to access CA server API.

For safety reasons the default is set to the Let's Encrypt staging server (for the ACME v1 protocol). This will create technically correct, but untrusted certificates.

For Let's Encrypt, all staging endpoints can be found here: https://letsencrypt.org/docs/staging-environment/

For Let's Encrypt, the production directory URL for ACME v1 is https://acme-v01.api.letsencrypt.org/directory, and the production directory URL for ACME v2 is https://acme-v02.api.letsencrypt.org/directory.

Warning: So far, the module has only been tested against Let's Encrypt (staging and production) and against the Pebble testing server.

acme_version

-

added in 2.5

  • 1

  • 2

The ACME version of the endpoint.

Must be 1 for the classic Let's Encrypt ACME endpoint, or 2 for the new standardized ACME v2 endpoint.

agreement

-

URI to a terms of service document you agree to when using the ACME v1 service at acme_directory.

Default is latest gathered from acme_directory URL.

This option will only be used when acme_version is 1.

chain_dest

-

added in 2.5

If specified, the intermediate certificate will be written to this file.


aliases: chain

challenge

-

  • http-01

  • dns-01
  • tls-alpn-01

The challenge to be performed.

csr

- / required

File containing the CSR for the new certificate.

Can be created with openssl req ....

The CSR may contain multiple Subject Alternate Names, but each one will lead to an individual challenge that must be fulfilled for the CSR to be signed.

Note: the private key used to create the CSR must not be the account key. This is a bad idea from a security point of view, and the CA should not accept the CSR. The ACME server should return an error in this case.


aliases: src

data

-

The data to validate ongoing challenges. This must be specified for the second run of the module only.

The value that must be used here will be provided by a previous use of this module. See the examples for more details.

Note that for ACME v2, only the order_uri entry of data will be used. For ACME v1, data must be non-empty to indicate the second stage is active; all needed data will be taken from the CSR.

Note: the data option was marked as no_log up to Ansible 2.5. From Ansible 2.6 on, it is no longer marked this way as it causes error messages to be come unusable, and data does not contain any information which can be used without having access to the account key or which are not public anyway.

deactivate_authzs

boolean

added in 2.6

  • no

  • yes

Deactivate authentication objects (authz) after issuing a certificate, or when issuing the certificate failed.

Authentication objects are bound to an account key and remain valid for a certain amount of time, and can be used to issue certificates without having to re-authenticate the domain. This can be a security concern.

dest

-

The destination file for the certificate.

Required if fullchain_dest is not specified.


aliases: cert

force

boolean

added in 2.6

  • no

  • yes

Enforces the execution of the challenge and validation, even if an existing certificate is still valid for more than remaining_days.

This is especially helpful when having an updated CSR e.g. with additional domains for which a new certificate is desired.

fullchain_dest

-

added in 2.5

The destination file for the full chain (i.e. certificate followed by chain of intermediate certificates).

Required if dest is not specified.


aliases: fullchain

modify_account

boolean

added in 2.6

  • no
  • yes

Boolean indicating whether the module should create the account if necessary, and update its contact data.

Set to no if you want to use the acme_account module to manage your account instead, and to avoid accidental creation of a new account using an old key if you changed the account key with acme_account.

If set to no, terms_agreed and account_email are ignored.

remaining_days

-

Default:

10

The number of days the certificate must have left being valid. If cert_days < remaining_days, then it will be renewed. If the certificate is not renewed, module return values will not include challenge_data.

To make sure that the certificate is renewed in any case, you can use the force option.

select_crypto_backend

string

added in 2.7

  • auto

  • cryptography
  • openssl

Determines which crypto backend to use. The default choice is auto, which tries to use cryptography if available, and falls back to openssl.

If set to openssl, will try to use the openssl binary.

If set to cryptography, will try to use the cryptography library.

terms_agreed

boolean

added in 2.5

  • no

  • yes

Boolean indicating whether you agree to the terms of service document.

ACME servers can require this to be true.

This option will only be used when acme_version is not 1.

validate_certs

boolean

added in 2.5

  • no
  • yes

Whether calls to the ACME directory will validate TLS certificates.

Warning: Should only ever be set to no for testing purposes, for example when testing against a local Pebble server.



Notes

Note

  • At least one of dest and fullchain_dest must be specified.
  • This module includes basic account management functionality. If you want to have more control over your ACME account, use the acme_account module and disable account management for this module using the modify_account option.
  • This module was called letsencrypt before Ansible 2.6. The usage did not change.
  • If you want to use the tls-alpn-01 challenge, you can use the acme_challenge_cert_helper module to prepare the challenge certificate.
  • You can use the certificate_complete_chain module to find the root certificate for the returned fullchain.
  • If a new enough version of the cryptography library is available (see Requirements for details), it will be used instead of the openssl binary. This can be explicitly disabled or enabled with the select_crypto_backend option. Note that using the openssl binary will be slower and less secure, as private key contents always have to be stored on disk (see account_key_content).
  • Although the defaults are chosen so that the module can be used with the Let’s Encrypt CA, the module can in principle be used with any CA providing an ACME endpoint.


Examples

### Example with HTTP challenge ###

- name: Create a challenge for sample.com using a account key from a variable.
  acme_certificate:
    account_key_content: "{{ account_private_key }}"
    csr: /etc/pki/cert/csr/sample.com.csr
    dest: /etc/httpd/ssl/sample.com.crt
  register: sample_com_challenge

# Alternative first step:
- name: Create a challenge for sample.com using a account key from hashi vault.
  acme_certificate:
    account_key_content: "{{ lookup('hashi_vault', 'secret=secret/account_private_key:value') }}"
    csr: /etc/pki/cert/csr/sample.com.csr
    fullchain_dest: /etc/httpd/ssl/sample.com-fullchain.crt
  register: sample_com_challenge

# Alternative first step:
- name: Create a challenge for sample.com using a account key file.
  acme_certificate:
    account_key_src: /etc/pki/cert/private/account.key
    csr: /etc/pki/cert/csr/sample.com.csr
    dest: /etc/httpd/ssl/sample.com.crt
    fullchain_dest: /etc/httpd/ssl/sample.com-fullchain.crt
  register: sample_com_challenge

# perform the necessary steps to fulfill the challenge
# for example:
#
# - copy:
#     dest: /var/www/html/{{ sample_com_challenge['challenge_data']['sample.com']['http-01']['resource'] }}
#     content: "{{ sample_com_challenge['challenge_data']['sample.com']['http-01']['resource_value'] }}"
#     when: sample_com_challenge is changed

- name: Let the challenge be validated and retrieve the cert and intermediate certificate
  acme_certificate:
    account_key_src: /etc/pki/cert/private/account.key
    csr: /etc/pki/cert/csr/sample.com.csr
    dest: /etc/httpd/ssl/sample.com.crt
    fullchain_dest: /etc/httpd/ssl/sample.com-fullchain.crt
    chain_dest: /etc/httpd/ssl/sample.com-intermediate.crt
    data: "{{ sample_com_challenge }}"

### Example with DNS challenge against production ACME server ###

- name: Create a challenge for sample.com using a account key file.
  acme_certificate:
    account_key_src: /etc/pki/cert/private/account.key
    account_email: [email protected]
    src: /etc/pki/cert/csr/sample.com.csr
    cert: /etc/httpd/ssl/sample.com.crt
    challenge: dns-01
    acme_directory: https://acme-v01.api.letsencrypt.org/directory
    # Renew if the certificate is at least 30 days old
    remaining_days: 60
  register: sample_com_challenge

# perform the necessary steps to fulfill the challenge
# for example:
#
# - route53:
#     zone: sample.com
#     record: "{{ sample_com_challenge.challenge_data['sample.com']['dns-01'].record }}"
#     type: TXT
#     ttl: 60
#     state: present
#     wait: yes
#     # Note: route53 requires TXT entries to be enclosed in quotes
#     value: "{{ sample_com_challenge.challenge_data['sample.com']['dns-01'].resource_value | regex_replace('^(.*)$', '\"\\1\"') }}"
#   when: sample_com_challenge is changed
#
# Alternative way:
#
# - route53:
#     zone: sample.com
#     record: "{{ item.key }}"
#     type: TXT
#     ttl: 60
#     state: present
#     wait: yes
#     # Note: item.value is a list of TXT entries, and route53
#     # requires every entry to be enclosed in quotes
#     value: "{{ item.value | map('regex_replace', '^(.*)$', '\"\\1\"' ) | list }}"
#   with_dict: sample_com_challenge.challenge_data_dns
#   when: sample_com_challenge is changed

- name: Let the challenge be validated and retrieve the cert and intermediate certificate
  acme_certificate:
    account_key_src: /etc/pki/cert/private/account.key
    account_email: [email protected]
    src: /etc/pki/cert/csr/sample.com.csr
    cert: /etc/httpd/ssl/sample.com.crt
    fullchain: /etc/httpd/ssl/sample.com-fullchain.crt
    chain: /etc/httpd/ssl/sample.com-intermediate.crt
    challenge: dns-01
    acme_directory: https://acme-v01.api.letsencrypt.org/directory
    remaining_days: 60
    data: "{{ sample_com_challenge }}"
  when: sample_com_challenge is changed

Return Values

Common return values are documented here, the following are the fields unique to this module:

Key Returned Description

account_uri

string

added in 2.5

changed

ACME account URI.


authorizations

complex

changed

ACME authorization data.


authorization

dictionary

success

ACME authorization object. See https://tools.ietf.org/html/rfc8555#section-7.1.4


cert_days

integer

success

the number of days the certificate remains valid.


challenge_data

complex

changed

per domain / challenge type challenge data


record

string

added in 2.5

changed and challenge is dns-01

the full DNS record's name for the challenge


Sample:

_acme-challenge.example.com

resource

string

changed

the challenge resource that must be created for validation


Sample:

.well-known/acme-challenge/evaGxfADs6pSRb2LAv9IZf17Dt3juxGJ-PCt92wr-oA

resource_value

string

changed

The value the resource has to produce for the validation.

For http-01 and dns-01 challenges, the value can be used as-is.

For tls-alpn-01 challenges, note that this return value contains a Base64 encoded version of the correct binary blob which has to be put into the acmeValidation x509 extension; see https://tools.ietf.org/html/draft-ietf-acme-tls-alpn-05#section-3 for details. To do this, you might need the b64decode Jinja filter to extract the binary blob from this return value.


Sample:

IlirfxKKXA...17Dt3juxGJ-PCt92wr-oA

challenge_data_dns

dictionary

added in 2.5

changed

list of TXT values per DNS record, in case challenge is dns-01


finalization_uri

string

added in 2.5

changed

ACME finalization URI.


order_uri

string

added in 2.5

changed

ACME order URI.





Status

Authors

  • Michael Gruener (@mgruener)

Hint

If you notice any issues in this documentation you can edit this document to improve it.


© 2012–2018 Michael DeHaan
© 2018–2019 Red Hat, Inc.
Licensed under the GNU General Public License version 3.
https://docs.ansible.com/ansible/2.7/modules/acme_certificate_module.html