letsencrypt.client

Let’s Encrypt client API.

letsencrypt.client.acme_from_config_key(config, key)

Wrangle ACME client construction

letsencrypt.client._determine_user_agent(config)

Set a user_agent string in the config based on the choice of plugins. (this wasn’t knowable at construction time)

Returns:the client’s User-Agent string Return type:str

letsencrypt.client.register(config, account_storage, tos_cb=None)

Register new account with an ACME CA.

This function takes care of generating fresh private key, registering the account, optionally accepting CA Terms of Service and finally saving the account. It should be called prior to initialization of Client, unless account has already been created.

Parameters:

• config (IConfig) – Client configuration.
• account_storage (AccountStorage) – Account storage where newly registered account will be saved to. Save happens only after TOS acceptance step, so any account private keys or RegistrationResource will not be persisted if tos_cb returns False.
• tos_cb – If ACME CA requires the user to accept a Terms of Service before registering account, client action is necessary. For example, a CLI tool would prompt the user acceptance. tos_cb must be a callable that should accept RegistrationResource and return a bool: True iff the Terms of Service present in the contained Registration.terms_of_service is accepted by the client, and False otherwise. tos_cb will be called only if the client acction is necessary, i.e. when terms_of_service is not None. This argument is optional, if not supplied it will default to automatic acceptance!

Raises:

• letsencrypt.errors.Error – In case of any client problems, in particular registration failure, or unaccepted Terms of Service.
• acme.errors.Error – In case of any protocol problems.

Returns:

Newly registered and saved account, as well as protocol API handle (should be used in Client initialization).

Return type:

tuple of Account and acme.client.Client

letsencrypt.client.perform_registration(acme, config)

Actually register new account, trying repeatedly if there are email problems

Parameters:

• config (IConfig) – Client configuration.
• client (acme.client.Client) – ACME client object.

Returns:

Registration Resource.

Return type:

acme.messages.RegistrationResource

Raises .UnexpectedUpdate:  

class letsencrypt.client.Client(config, account_, dv_auth, installer, acme=None)

Bases: object

ACME protocol client.

Variables:

• config (IConfig) – Client configuration.
• account (Account) – Account registered with register.
• auth_handler (AuthHandler) – Authorizations handler that will dispatch DV and Continuity challenges to appropriate authenticators (providing IAuthenticator interface).
• dv_auth (IAuthenticator) – Prepared (IAuthenticator.prepare) authenticator that can solve the constants.DV_CHALLENGES.
• installer (IInstaller) – Installer.
• acme (acme.client.Client) – Optional ACME client API handle. You might already have one from register.

_obtain_certificate(domains, csr)

Obtain certificate.

Internal function with precondition that domains are consistent with identifiers present in the csr.

Parameters:

• domains (list) – Domain names.
• csr (le_util.CSR) – DER-encoded Certificate Signing Request. The key used to generate this CSR can be different than authkey.

Returns:

CertificateResource and certificate chain (as returned by fetch_chain).

Return type:

tuple

obtain_certificate_from_csr(csr)

Obtain certficiate from CSR.

Parameters:csr (le_util.CSR) – DER-encoded Certificate Signing Request. Returns:CertificateResource and certificate chain (as returned by fetch_chain). Return type:tuple

obtain_certificate(domains)

Obtains a certificate from the ACME server.

register must be called before obtain_certificate

Parameters:domains (set) – domains to get a certificate Returns:CertificateResource, certificate chain (as returned by fetch_chain), and newly generated private key (le_util.Key) and DER-encoded Certificate Signing Request (le_util.CSR). Return type:tuple

obtain_and_enroll_certificate(domains)

Obtain and enroll certificate.

Get a new certificate for the specified domains using the specified authenticator and installer, and then create a new renewable lineage containing it.

Parameters:

• domains (list) – Domains to request.
• plugins – A PluginsFactory object.

Returns:

A new letsencrypt.storage.RenewableCert instance referred to the enrolled cert lineage, or False if the cert could not be obtained.

save_certificate(certr, chain_cert, cert_path, chain_path, fullchain_path)

Saves the certificate received from the ACME server.

Parameters:

• certr (acme.messages.Certificate) – ACME “certificate” resource.
• chain_cert (list) –
• cert_path (str) – Candidate path to a certificate.
• chain_path (str) – Candidate path to a certificate chain.
• fullchain_path (str) – Candidate path to a full cert chain.

Returns:

cert_path, chain_path, and fullchain_path as absolute paths to the actual files

Return type:

tuple of str

Raises IOError:

If unable to find room to write the cert files

deploy_certificate(domains, privkey_path, cert_path, chain_path, fullchain_path)

Install certificate

Parameters:

• domains (list) – list of domains to install the certificate
• privkey_path (str) – path to certificate private key
• cert_path (str) – certificate file path (optional)
• chain_path (str) – chain file path

enhance_config(domains, config)

Enhance the configuration.

Parameters:domains (list) – list of domains to configure Variables:config – Namespace typically produced by argparse.ArgumentParser.parse_args(). it must have the redirect, hsts and uir attributes. Raises .errors.Error:  if no installer is specified in the client.

apply_enhancement(domains, enhancement, options=None)

Applies an enhacement on all domains.

Parameters:domains – list of ssl_vhosts

:type list of str

Parameters:enhancement – name of enhancement, e.g. ensure-http-header

:type str

Note

when more options are need make options a list.

Parameters:options – options to enhancement, e.g. Strict-Transport-Security

:type str

Raises .errors.PluginError:  If Enhancement is not supported, or if there is any other problem with the enhancement.

_recovery_routine_with_msg(success_msg)

Calls the installer’s recovery routine and prints success_msg

Parameters:success_msg (str) – message to show on successful recovery

_rollback_and_restart(success_msg)

Rollback the most recent checkpoint and restart the webserver

Parameters:success_msg (str) – message to show on successful rollback

letsencrypt.client.validate_key_csr(privkey, csr=None)

Validate Key and CSR files.

Verifies that the client key and csr arguments are valid and correspond to one another. This does not currently check the names in the CSR due to the inability to read SANs from CSRs in python crypto libraries.

If csr is left as None, only the key will be validated.

Parameters:

• privkey (letsencrypt.le_util.Key) – Key associated with CSR
• csr (le_util.CSR) – CSR

Raises .errors.Error:  

when validation fails

letsencrypt.client.rollback(default_installer, checkpoints, config, plugins)

Revert configuration the specified number of checkpoints.

Parameters:

• checkpoints (int) – Number of checkpoints to revert.
• config (letsencrypt.interfaces.IConfig) – Configuration.

letsencrypt.client.view_config_changes(config)

View checkpoints and associated configuration changes.

Note

This assumes that the installation is using a Reverter object.

Parameters:config (letsencrypt.interfaces.IConfig) – Configuration.

letsencrypt.client._save_chain(chain_pem, chain_path)

Saves chain_pem at a unique path based on chain_path.

Parameters:

• chain_pem (str) – certificate chain in PEM format
• chain_path (str) – candidate path for the cert chain

Returns:

absolute path to saved cert chain

Return type:

str